chore: bump version to 1.16

- 修复备份自身应用时 force-stop 导致闪退（加入 context.packageName 排除）
- 流式备份重写：放弃 FIFO + --stdin，改用临时目录 + 标准 restic backup，支持 SMB/WebDAV
- 流式备份目录结构改为 per-app 子目录，与普通备份兼容
- 配置页新增「导入配置」按钮（importConfig）
- 修复导入配置后密码丢失（密码占位符 stored-in-keystore 未从 PasswordManager 恢复）
- 修复 RestoreScreen 恢复操作缺少 cacheDir/backendDomain 配置
- 修复 REST 桥 HEAD /config 在 SMB 下假阴性（回退到 download 确认）
- 修复 isArchiveSafe 安全检测拒绝 /data/data/ 和 /data/user_de/ 路径
- 修正流式备份中 zstd 二进制路径（cacheDir.parentFile 少一层 files/）
- loadResticSnapshot/loadResticAppDetails 兼容新旧流式备份目录结构
- 新增 BackupViewModel、BackendExecutor、PasswordManager 等文件

.pi/wow.yaml

@@ -0,0 +1,10 @@
+# Project-level wow-pi configuration for android-backup-gui
+contexts:
+  - AGENTS.md
+  - docs/contexts/*.md
+
+inject:
+  enabled: true
+  overrideExisting: false
+  envFiles:
+    - .env

AGENTS.md

@@ -1,7 +1,7 @@
 <!-- gitnexus:start -->
 # GitNexus — Code Intelligence
 
-This project is indexed by GitNexus as **android-backup-gui** (1684 symbols, 4068 relationships, 146 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.
+This project is indexed by GitNexus as **android-backup-gui** (1734 symbols, 4049 relationships, 110 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.
 
 > If any GitNexus tool warns the index is stale, run `npx gitnexus analyze` in terminal first.
 

CLAUDE.md

@@ -1,7 +1,7 @@
 <!-- gitnexus:start -->
 # GitNexus — Code Intelligence
 
-This project is indexed by GitNexus as **android-backup-gui** (1684 symbols, 4068 relationships, 146 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.
+This project is indexed by GitNexus as **android-backup-gui** (1734 symbols, 4049 relationships, 110 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.
 
 > If any GitNexus tool warns the index is stale, run `npx gitnexus analyze` in terminal first.
 

app/build.gradle

@@ -24,8 +24,8 @@ android {
         applicationId "com.example.androidbackupgui"
         minSdk 24
         targetSdk 34
-        versionCode 15
-        versionName "1.15"
+        versionCode 16
+        versionName "1.16"
     }
     buildFeatures {
         compose = true
@@ -97,6 +97,7 @@ dependencies {
 
     implementation "org.jetbrains.kotlin:kotlin-stdlib:1.9.0"
     implementation 'androidx.core:core-ktx:1.12.0'
+    implementation 'androidx.security:security-crypto:1.1.0-alpha06'
     implementation 'androidx.appcompat:appcompat:1.6.1'
     implementation 'com.google.android.material:material:1.11.0'
     implementation 'androidx.lifecycle:lifecycle-runtime-ktx:2.7.0'

app/src/main/java/com/example/androidbackupgui/MainActivity.kt

@@ -1,23 +1,23 @@
 package com.example.androidbackupgui
-
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
 import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.material3.Surface
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
 import androidx.compose.ui.Modifier
 import com.example.androidbackupgui.backup.LogUtil
+import com.example.androidbackupgui.backup.MissingAlgoProvider
+import com.example.androidbackupgui.backup.PasswordManager
 import com.example.androidbackupgui.backup.ResticBinary
-import com.example.androidbackupgui.backup.ResticWrapper
+import com.example.androidbackupgui.backup.defaultResticWrapper
 import com.example.androidbackupgui.root.RootShell
 import com.example.androidbackupgui.ui.AppScaffold
 import com.example.androidbackupgui.ui.theme.AppTheme
 import com.google.android.material.color.DynamicColors
 
 class MainActivity : ComponentActivity() {
-
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         enableEdgeToEdge()
@@ -27,16 +27,19 @@ class MainActivity : ComponentActivity() {
         RootShell.configure()
 
         // Initialize restic binary path
-        ResticBinary.prepare(this)?.let { ResticWrapper.binaryPath = it }
+        ResticBinary.prepare(this)?.let { defaultResticWrapper.binaryPath = it }
 
-        // Initialize file-based logging
+        // Initialize file-based logging and secure credential storage
         LogUtil.init(filesDir)
+        PasswordManager.init(this)
+        // 启动时初始化 SMB 加密库（MD4/AESCMAC），避免首次 SMB 操作时延迟失败
+        MissingAlgoProvider.register()
 
         setContent {
             AppTheme {
                 Surface(
                     modifier = Modifier.fillMaxSize(),
-                    color = MaterialTheme.colorScheme.background
+                    color = MaterialTheme.colorScheme.background,
                 ) {
                     AppScaffold()
                 }

app/src/main/java/com/example/androidbackupgui/backup/BackendExecutor.kt

@@ -0,0 +1,136 @@
+package com.example.androidbackupgui.backup
+
+import java.io.File
+
+/**
+ * 后端执行器——消除 [ResticBackup]、[ResticRestore]、[ResticSnapshotOps]、
+ * [ResticMaintenance] 和 [ResticRepoInit] 中重复的 local-vs-remote 分支。
+ *
+ * 使用方式（替换所有子模块中的 if backend == "local" 模式）：
+ *
+ * ```
+ * executor.withBackend(
+ *     repoPath = repoPath, password = password, cacheDir = cacheDir,
+ *     backend = backend, backendUrl = backendUrl,
+ *     backendUser = backendUser, backendPass = backendPass,
+ *     backendShare = backendShare, backendDomain = backendDomain,
+ *     runner = runner, envResolver = envResolver, bridgeRunner = bridgeRunner,
+ * ) { env ->
+ *     val result = runner.runRestic(env, args)
+ *     // parse result
+ * }
+ * ```
+ */
+class BackendExecutor {
+    /**
+     * 使用 [block] 执行 restic 操作。
+     *
+     * - "local" 后端：直接通过 [ResticEnvResolver.buildLocalEnv] 构建环境
+     * - 远程后端：通过 [RestBridgeRunner.withBridge] 启动 REST 桥后再构建环境
+     *
+     * @param T 返回值的类型（例如 [AppResult]）
+     * @param block 接收环境变量 Map，返回 [T]
+     */
+    suspend fun <T> withBackend(
+        repoPath: String,
+        password: String,
+        cacheDir: String,
+        backend: String,
+        backendUrl: String,
+        backendUser: String,
+        backendPass: String,
+        backendShare: String,
+        backendDomain: String,
+        runner: ResticCommandRunner,
+        envResolver: ResticEnvResolver,
+        bridgeRunner: RestBridgeRunner,
+        block: suspend (Map<String, String>) -> T,
+    ): T {
+        if (backend == "local") {
+            val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
+            return block(env)
+        }
+        return bridgeRunner.withBridge(
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+            backendDomain,
+            repoPath,
+            File(cacheDir),
+        ) { bridgeUrl, authToken ->
+            val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
+            block(env)
+        }
+    }
+
+    /**
+     * 与 [withBackend] 相同，但自动将 [args] 传给 [runner.runRestic]。
+     *
+     * 适用于 "run-and-parse-exit-code" 模式的简化调用。
+     */
+    suspend fun runResticWithBackend(
+        args: List<String>,
+        repoPath: String,
+        password: String,
+        cacheDir: String,
+        backend: String,
+        backendUrl: String,
+        backendUser: String,
+        backendPass: String,
+        backendShare: String,
+        backendDomain: String,
+        runner: ResticCommandRunner,
+        envResolver: ResticEnvResolver,
+        bridgeRunner: RestBridgeRunner,
+    ): ResticCommandRunner.CommandResult =
+        withBackend(
+            repoPath = repoPath,
+            password = password,
+            cacheDir = cacheDir,
+            backend = backend,
+            backendUrl = backendUrl,
+            backendUser = backendUser,
+            backendPass = backendPass,
+            backendShare = backendShare,
+            backendDomain = backendDomain,
+            runner = runner,
+            envResolver = envResolver,
+            bridgeRunner = bridgeRunner,
+        ) { env -> runner.runRestic(env, args) }
+
+    /**
+     * 与 [runResticWithBackend] 相同，但使用流式模式。
+     */
+    suspend fun runResticStreamingWithBackend(
+        args: List<String>,
+        repoPath: String,
+        password: String,
+        cacheDir: String,
+        backend: String,
+        backendUrl: String,
+        backendUser: String,
+        backendPass: String,
+        backendShare: String,
+        backendDomain: String,
+        runner: ResticCommandRunner,
+        envResolver: ResticEnvResolver,
+        bridgeRunner: RestBridgeRunner,
+        onLine: suspend (String) -> Unit = {},
+    ): ResticCommandRunner.CommandResult =
+        withBackend(
+            repoPath = repoPath,
+            password = password,
+            cacheDir = cacheDir,
+            backend = backend,
+            backendUrl = backendUrl,
+            backendUser = backendUser,
+            backendPass = backendPass,
+            backendShare = backendShare,
+            backendDomain = backendDomain,
+            runner = runner,
+            envResolver = envResolver,
+            bridgeRunner = bridgeRunner,
+        ) { env -> runner.runResticStreaming(env, args, onLine) }
+}

app/src/main/java/com/example/androidbackupgui/backup/BackupConfig.kt

@@ -1,7 +1,7 @@
 package com.example.androidbackupgui.backup
 
-import java.io.File
 import kotlinx.serialization.Serializable
+import java.io.File
 
 /**
  * Mirrors backup_settings.conf from backup_script.
@@ -12,68 +12,68 @@ import kotlinx.serialization.Serializable
 @Serializable
 data class BackupConfig(
     // Operation mode
-    val lo: Int = 0,                        // 0=volume key, 1=volume force, 2=keyboard
-    val backgroundExecution: Int = 0,       // 0=foreground, 1=background
-    val setDisplayPowerMode: Int = 0,       // 1=keep screen on during backup
-    val shellLang: String = "",             // ""=auto, "1"=zh-CN, "0"=zh-TW
-
+    val lo: Int = 0, // 0=volume key, 1=volume force, 2=keyboard
+    val backgroundExecution: Int = 0, // 0=foreground, 1=background
+    val setDisplayPowerMode: Int = 0, // 1=keep screen on during backup
+    val shellLang: String = "", // ""=auto, "1"=zh-CN, "0"=zh-TW
     // Paths
-    val outputPath: String = "",            // Custom output dir
-    val listLocation: String = "",          // Custom appList.txt location
-
+    val outputPath: String = "", // Custom output dir
+    val listLocation: String = "", // Custom appList.txt location
     // Update
-    val update: Int = 1,                    // 1=auto update
-    val cdn: Int = 1,                       // CDN node
-
+    val update: Int = 1, // 1=auto update
+    val cdn: Int = 1, // CDN node
     // Filters
     val mountPoint: String = "rannki|0000-1",
     val user: String = "",
-
     // Backup mode
-    val backupMode: Int = 1,                // 1=data+apk, 0=apk only
+    val backupMode: Int = 1, // 1=data+apk, 0=apk only
     val backupUserData: Int = 1,
     val backupObbData: Int = 1,
     val backupMedia: Int = 0,
     val backgroundAppsIgnore: Int = 0,
-    val backupUserId: Int = 0,              // Android user ID (0=Owner)
-
+    val backupUserId: Int = 0, // Android user ID (0=Owner)
     // Custom paths
-    val customPath: List<String> = listOf(
-        "/storage/emulated/0/Pictures/",
-        "/storage/emulated/0/Download/",
-        "/storage/emulated/0/Music",
-        "/storage/emulated/0/DCIM/",
-        "/data/adb"
-    ),
-
+    val customPath: List<String> =
+        listOf(
+            "/storage/emulated/0/Pictures/",
+            "/storage/emulated/0/Download/",
+            "/storage/emulated/0/Music",
+            "/storage/emulated/0/DCIM/",
+            "/data/adb",
+        ),
     // Blacklist
-    val blacklistMode: Int = 0,             // 1=full ignore, 0=apk only
+    val blacklistMode: Int = 0, // 1=full ignore, 0=apk only
     val blacklist: List<String> = emptyList(),
-
     // Whitelists
     val whitelist: List<String> = emptyList(),
     val system: List<String> = emptyList(),
-
     // Compression
     val compressionMethod: String = "zstd", // zstd or tar
-
     // Terminal colors
     val rgbA: Int = 226,
     val rgbB: Int = 123,
     val rgbC: Int = 177,
-
     val backupWifi: Int = 1,
-
     // Restic deduplicated backup with rclone backend
     val resticEnabled: Int = 0,
     val resticRepo: String = "",
+    /**
+     * restic 密码不在配置文件中明文存储。始终通过 PasswordManager 存取。
+     * 此字段仅保留默认值，用于反序列化兼容旧版配置文件。
+     */
+    @Deprecated("Use PasswordManager.getResticPassword() instead; kept only for config file backward compat")
     val resticPassword: String = "",
-    val resticBackend: String = "local",    // local / webdav / smb
+    val resticBackend: String = "local", // local / webdav / smb
     val resticBackendUrl: String = "",
     val resticBackendUser: String = "",
+    /** @deprecated Use PasswordManager instead */
+    @Deprecated("Use PasswordManager instead")
     val resticBackendPass: String = "",
-    val resticBackendShare: String = "",      // SMB share name
-    val resticBackendDomain: String = ""      // SMB domain (optional, for NTLM)
+    val resticBackendShare: String = "", // SMB share name
+    val resticBackendDomain: String = "", // SMB domain (optional, for NTLM)
+    // Streaming backup: pipe tar data through FIFO directly into restic --stdin
+    // 0=disabled (default, stable), 1=enabled (experimental, avoids temp files)
+    val useStreaming: Int = 0,
 ) {
     companion object {
         /**
@@ -87,29 +87,37 @@ data class BackupConfig(
             while (i < s.length) {
                 val c = s[i]
                 if (c == '\\' && i + 1 < s.length) {
-                    sb.append(s[i + 1]); i += 2
+                    sb.append(s[i + 1])
+                    i += 2
                 } else {
-                    sb.append(c); i++
+                    sb.append(c)
+                    i++
                 }
             }
             return sb.toString()
         }
 
         /** Escape a value for safe storage inside double quotes. */
-        private fun escapeValue(s: String): String =
-            s.replace("\\", "\\\\").replace("\"", "\\\"")
+        private fun escapeValue(s: String): String = s.replace("\\", "\\\\").replace("\"", "\\\"")
 
         fun fromFile(file: File): BackupConfig {
             if (!file.exists()) return BackupConfig()
 
             // Quoted-string fields preserve their inner whitespace and may contain
             // escaped characters; bare fields are trimmed as before.
-            val quotedKeys = setOf(
-                "Output_path", "list_location", "mount_point",
-                "restic_repo", "restic_password", "restic_backend_url",
-                "restic_backend_user", "restic_backend_pass",
-                "restic_backend_share", "restic_backend_domain"
-            )
+            val quotedKeys =
+                setOf(
+                    "Output_path",
+                    "list_location",
+                    "mount_point",
+                    "restic_repo",
+                    "restic_password",
+                    "restic_backend_url",
+                    "restic_backend_user",
+                    "restic_backend_pass",
+                    "restic_backend_share",
+                    "restic_backend_domain",
+                )
 
             val props = mutableMapOf<String, String>()
             file.forEachLine { line ->
@@ -119,27 +127,34 @@ data class BackupConfig(
                 if (eq < 0) return@forEachLine
                 val key = trimmed.substring(0, eq).trim()
                 val rawValue = trimmed.substring(eq + 1)
-                props[key] = if (key in quotedKeys) {
-                    // Strip the surrounding quotes (if present) WITHOUT trimming the
-                    // inner content, so leading/trailing spaces in e.g. a password
-                    // survive a save/load round trip. Then unescape.
-                    val v = rawValue
-                    if (v.length >= 2 && v.startsWith("\"") && v.endsWith("\"")) {
-                        unescapeValue(v.substring(1, v.length - 1))
+                props[key] =
+                    if (key in quotedKeys) {
+                        // Strip the surrounding quotes (if present) WITHOUT trimming the
+                        // inner content, so leading/trailing spaces in e.g. a password
+                        // survive a save/load round trip. Then unescape.
+                        val v = rawValue
+                        if (v.length >= 2 && v.startsWith("\"") && v.endsWith("\"")) {
+                            unescapeValue(v.substring(1, v.length - 1))
+                        } else {
+                            // Legacy/unquoted value — fall back to trimmed form.
+                            unescapeValue(v.trim().removeSurrounding("\""))
+                        }
                     } else {
-                        // Legacy/unquoted value — fall back to trimmed form.
-                        unescapeValue(v.trim().removeSurrounding("\""))
+                        rawValue.trim().removeSurrounding("\"")
                     }
-                } else {
-                    rawValue.trim().removeSurrounding("\"")
-                }
             }
 
-            fun int(key: String, default: Int = 0) = props[key]?.toIntOrNull() ?: default
+            fun int(
+                key: String,
+                default: Int = 0,
+            ) = props[key]?.toIntOrNull() ?: default
+
             fun str(key: String) = props[key] ?: ""
+
             fun lines(key: String): List<String> {
                 val raw = props[key] ?: return emptyList()
-                return raw.split("\\s+".toRegex())
+                return raw
+                    .split("\\s+".toRegex())
                     .filter { it.isNotBlank() && it != "\"\"" }
                     .map { it.replace("%20", " ") }
             }
@@ -173,66 +188,75 @@ data class BackupConfig(
                 backupWifi = int("backup_wifi", default = 1),
                 resticEnabled = int("restic_enabled"),
                 resticRepo = str("restic_repo"),
-                resticPassword = str("restic_password"),
+                resticPassword = "", // 不用配置文件中的值，见下方迁移逻辑
                 resticBackend = str("restic_backend").ifEmpty { "local" },
                 resticBackendUrl = str("restic_backend_url"),
                 resticBackendUser = str("restic_backend_user"),
-                resticBackendPass = str("restic_backend_pass"),
+                resticBackendPass = "", // 不用配置文件中的值
                 resticBackendShare = str("restic_backend_share"),
                 resticBackendDomain = str("restic_backend_domain"),
+                useStreaming = int("streaming_backup"),
             )
         }
 
-        fun toFile(config: BackupConfig, file: File) {
+        fun toFile(
+            config: BackupConfig,
+            file: File,
+        ) {
             file.parentFile?.mkdirs()
-            file.writeText(buildString {
-                appendLine("# SpeedBackup Configuration")
-                appendLine("Lo=${config.lo}")
-                appendLine("background_execution=${config.backgroundExecution}")
-                appendLine("setDisplayPowerMode=${config.setDisplayPowerMode}")
-                appendLine("Shell_LANG=${config.shellLang}")
-                appendLine("Output_path=\"${escapeValue(config.outputPath)}\"")
-                appendLine("list_location=\"${escapeValue(config.listLocation)}\"")
-                appendLine("update=${config.update}")
-                appendLine("cdn=${config.cdn}")
-                appendLine("mount_point=\"${escapeValue(config.mountPoint)}\"")
-                appendLine("user=${config.user}")
-                appendLine("Backup_Mode=${config.backupMode}")
-                appendLine("Backup_user_data=${config.backupUserData}")
-                appendLine("Backup_obb_data=${config.backupObbData}")
-                appendLine("backup_media=${config.backupMedia}")
-                appendLine("backup_user_id=${config.backupUserId}")
-                appendLine("Background_apps_ignore=${config.backgroundAppsIgnore}")
-                append("Custom_path=\"")
-                config.customPath.forEach { append(" ${it.replace(" ", "%20")}") }
-                appendLine(" \"")
-                appendLine("blacklist_mode=${config.blacklistMode}")
-                append("blacklist=\"")
-                config.blacklist.forEach { append(" ${it.replace(" ", "%20")}") }
-                appendLine(" \"")
-                append("whitelist=\"")
-                config.whitelist.forEach { append(" ${it.replace(" ", "%20")}") }
-                appendLine(" \"")
-                append("system=\"")
-                config.system.forEach { append(" ${it.replace(" ", "%20")}") }
-                appendLine(" \"")
-                appendLine("Compression_method=${config.compressionMethod}")
-                appendLine("rgb_a=${config.rgbA}")
-                appendLine("rgb_b=${config.rgbB}")
-                appendLine("rgb_c=${config.rgbC}")
-                appendLine("backup_wifi=${config.backupWifi}")
-                appendLine("restic_enabled=${config.resticEnabled}")
-                appendLine("restic_repo=\"${escapeValue(config.resticRepo)}\"")
-                appendLine("restic_password=\"${escapeValue(config.resticPassword)}\"")
-                appendLine("restic_backend=${config.resticBackend}")
-                appendLine("restic_backend_url=\"${escapeValue(config.resticBackendUrl)}\"")
-                appendLine("restic_backend_user=\"${escapeValue(config.resticBackendUser)}\"")
-                appendLine("restic_backend_pass=\"${escapeValue(config.resticBackendPass)}\"")
-                appendLine("restic_backend_share=\"${escapeValue(config.resticBackendShare)}\"")
-                appendLine("restic_backend_domain=\"${escapeValue(config.resticBackendDomain)}\"")
-            })
-            file.setReadable(true, true)   // owner only
-            file.setWritable(true, true)   // owner only
+            file.writeText(
+                buildString {
+                    appendLine("# SpeedBackup Configuration")
+                    appendLine("Lo=${config.lo}")
+                    appendLine("background_execution=${config.backgroundExecution}")
+                    appendLine("setDisplayPowerMode=${config.setDisplayPowerMode}")
+                    appendLine("Shell_LANG=${config.shellLang}")
+                    appendLine("Output_path=\"${escapeValue(config.outputPath)}\"")
+                    appendLine("list_location=\"${escapeValue(config.listLocation)}\"")
+                    appendLine("update=${config.update}")
+                    appendLine("cdn=${config.cdn}")
+                    appendLine("mount_point=\"${escapeValue(config.mountPoint)}\"")
+                    appendLine("user=${config.user}")
+                    appendLine("Backup_Mode=${config.backupMode}")
+                    appendLine("Backup_user_data=${config.backupUserData}")
+                    appendLine("Backup_obb_data=${config.backupObbData}")
+                    appendLine("backup_media=${config.backupMedia}")
+                    appendLine("backup_user_id=${config.backupUserId}")
+                    appendLine("Background_apps_ignore=${config.backgroundAppsIgnore}")
+                    append("Custom_path=\"")
+                    config.customPath.forEach { append(" ${it.replace(" ", "%20")}") }
+                    appendLine(" \"")
+                    appendLine("blacklist_mode=${config.blacklistMode}")
+                    append("blacklist=\"")
+                    config.blacklist.forEach { append(" ${it.replace(" ", "%20")}") }
+                    appendLine(" \"")
+                    append("whitelist=\"")
+                    config.whitelist.forEach { append(" ${it.replace(" ", "%20")}") }
+                    appendLine(" \"")
+                    append("system=\"")
+                    config.system.forEach { append(" ${it.replace(" ", "%20")}") }
+                    appendLine(" \"")
+                    appendLine("Compression_method=${config.compressionMethod}")
+                    appendLine("rgb_a=${config.rgbA}")
+                    appendLine("rgb_b=${config.rgbB}")
+                    appendLine("rgb_c=${config.rgbC}")
+                    appendLine("backup_wifi=${config.backupWifi}")
+                    appendLine("restic_enabled=${config.resticEnabled}")
+                    appendLine("restic_repo=\"${escapeValue(config.resticRepo)}\"")
+                    // 密码已存储在 KeyStore 中，配置文件中仅写入占位符
+                    appendLine("restic_password=\"stored-in-keystore\"")
+                    appendLine("restic_backend=${config.resticBackend}")
+                    appendLine("restic_backend_url=\"${escapeValue(config.resticBackendUrl)}\"")
+                    appendLine("restic_backend_user=\"${escapeValue(config.resticBackendUser)}\"")
+                    // 密码已存储在 KeyStore 中
+                    appendLine("restic_backend_pass=\"stored-in-keystore\"")
+                    appendLine("restic_backend_share=\"${escapeValue(config.resticBackendShare)}\"")
+                    appendLine("restic_backend_domain=\"${escapeValue(config.resticBackendDomain)}\"")
+                    appendLine("streaming_backup=${config.useStreaming}")
+                },
+            )
+            file.setReadable(true, true) // owner only
+            file.setWritable(true, true) // owner only
         }
     }
 }

app/src/main/java/com/example/androidbackupgui/backup/BackupOperation.kt

@@ -1,21 +1,22 @@
 package com.example.androidbackupgui.backup
 
+import android.util.Log
 import com.example.androidbackupgui.backup.ResticWrapper.SnapshotAppInfo
 import com.example.androidbackupgui.root.RootShell
-import android.util.Log
 import com.example.androidbackupgui.root.shellEscape
-import kotlinx.coroutines.ensureActive
 import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.withContext
-import java.io.File
-import org.json.JSONArray
-import org.json.JSONObject
-import kotlinx.serialization.Serializable
-import kotlinx.coroutines.coroutineScope
 import kotlinx.coroutines.async
 import kotlinx.coroutines.awaitAll
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.ensureActive
 import kotlinx.coroutines.sync.Semaphore
 import kotlinx.coroutines.sync.withPermit
+import kotlinx.coroutines.withContext
+import kotlinx.serialization.Serializable
+import org.json.JSONArray
+import org.json.JSONObject
+import java.io.File
+import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.atomic.AtomicInteger
 
 /**
@@ -23,7 +24,6 @@ import java.util.concurrent.atomic.AtomicInteger
  * Mirrors the logic from backup_script's modules/backup.sh.
  */
 object BackupOperation {
-
     private const val TAG = "BackupOperation"
 
     @Serializable
@@ -31,8 +31,8 @@ object BackupOperation {
         val current: Int,
         val total: Int,
         val packageName: String,
-        val stage: String,        // "apk", "data", "obb", "ssaid", "done"
-        val message: String
+        val stage: String, // "apk", "data", "obb", "ssaid", "done"
+        val message: String,
     )
 
     @Serializable
@@ -41,7 +41,7 @@ object BackupOperation {
         val failCount: Int,
         val skippedCount: Int,
         val outputDir: String,
-        val elapsedMs: Long
+        val elapsedMs: Long,
     )
 
     /**
@@ -65,149 +65,284 @@ object BackupOperation {
         noDataBackup: Set<String> = emptySet(),
         includePkgs: Set<String> = emptySet(),
         legacyApps: Map<String, SnapshotAppInfo>? = null,
-        onProgress: suspend (BackupProgress) -> Unit = {}
-    ): BackupResult = withContext(Dispatchers.IO) {
-        val emit: suspend (BackupProgress) -> Unit = { p -> withContext(Dispatchers.Main) { onProgress(p) } }
-        val startTime = System.currentTimeMillis()
+        onProgress: suspend (BackupProgress) -> Unit = {},
+    ): BackupResult =
+        withContext(Dispatchers.IO) {
+            val emit: suspend (BackupProgress) -> Unit = { p -> withContext(Dispatchers.Main) { onProgress(p) } }
+            val startTime = System.currentTimeMillis()
 
-        // Create backup structure
-        val backupRoot = File(outputDir, "Backup_${config.compressionMethod}_$userId")
-        if (!backupRoot.mkdirs() && !backupRoot.isDirectory) {
-            LogUtil.e(TAG, "backupApps: cannot create output dir ${backupRoot.absolutePath}")
-            return@withContext BackupResult(0, 0, 0, outputDir.absolutePath, 0)
-        }
-        LogUtil.i(TAG, "backupApps: starting backup of ${apps.size} apps to ${backupRoot.absolutePath}")
+            // Safety check: refuse to backup inside Android/data directories
+            val absOut = outputDir.absolutePath
+            if (absOut.contains("/Android/")) {
+                LogUtil.e(TAG, "backupApps: refusing to backup inside Android/ directory: $absOut")
+                return@withContext BackupResult(0, 0, 0, absOut, 0)
+            }
 
-        // Write app list — includes ALL packages in [apps] (selected + legacy from snapshot)
-        val appListFile = File(backupRoot, "appList.txt")
-        try {
-            appListFile.writeText(apps.joinToString("\n") { it.packageName.value })
-        } catch (e: Exception) {
-            LogUtil.e(TAG, "backupApps: failed to write appList.txt — ${e.message}")
-            return@withContext BackupResult(0, 0, 0, outputDir.absolutePath, 0)
-        }
+            // Create backup structure
+            val backupRoot = File(outputDir, "Backup_${config.compressionMethod}_$userId")
+            if (!mkdirsForBackup(backupRoot)) {
+                LogUtil.e(TAG, "backupApps: cannot create output dir ${backupRoot.absolutePath}")
+                return@withContext BackupResult(0, 0, 0, outputDir.absolutePath, 0)
+            }
+            LogUtil.i(TAG, "backupApps: starting backup of ${apps.size} apps to ${backupRoot.absolutePath}")
 
-        // Write metadata JSON — fresh metadata for selected apps, legacy for historical apps
-        val metaFile = File(backupRoot, "app_details.json")
-        try {
-            metaFile.writeText(buildAppDetailsJson(apps, legacyApps))
-        } catch (e: Exception) {
-            LogUtil.e(TAG, "backupApps: failed to write app_details.json — ${e.message}")
-            return@withContext BackupResult(0, 0, 0, outputDir.absolutePath, 0)
-        }
-
-        val backupTargets = if (includePkgs.isEmpty()) apps else apps.filter { it.packageName.value in includePkgs }
-        val totalCount = backupTargets.size
-        LogUtil.i(TAG, "backupApps: includePkgs=${includePkgs.size} targets=$totalCount")
-        val semaphore = Semaphore(3)
-        val successAtomic = AtomicInteger(0)
-        val failAtomic = AtomicInteger(0)
-        val skippedAtomic = AtomicInteger(0)
-
-        coroutineScope {
-            backupTargets.mapIndexed { index, app ->
-                async {
-                    semaphore.withPermit {
-                        ensureActive()
-                        val appDir = File(backupRoot, app.packageName.value)
-                        appDir.mkdirs()
-
-                        emit(BackupProgress(index + 1, totalCount, app.packageName.value, "apk", "正在备份 APK…"))
-
-                        // 1. Backup APK
-                        val paths = AppScanner.getApkPaths(app.packageName.value)
-                        val apkOk = if (paths.isNotEmpty()) {
-                            paths.withIndex().all { (i, apkPath) ->
-                                val destName = if (paths.size > 1) "${app.packageName}_split_$i.apk" else "${app.packageName}.apk"
-                                RootShell.exec("cp '${apkPath.shellEscape()}' '${appDir.absolutePath.shellEscape()}/${destName.shellEscape()}'").isSuccess
-                            }
-                        } else false
-
-                        if (!apkOk) {
-                            failAtomic.incrementAndGet()
-                            emit(BackupProgress(index + 1, totalCount, app.packageName.value, "done", "APK 备份失败"))
-                            return@withPermit
-                        }
-
-                        // 1.5 Keystore check — warn if app has keystore entries (keys can be lost)
-                        val hasKeystore = AppScanner.hasKeystore(app.packageName.value)
-                        if (hasKeystore) {
-                            emit(BackupProgress(index + 1, totalCount, app.packageName.value, "data", "⚠ 此应用包含密钥库条目，备份后密钥可能会丢失"))
-                        }
-
-                        // 2. Backup user data (if configured)
-                        if (config.backupMode == 1 && config.backupUserData == 1) {
-                            if (app.packageName.value in noDataBackup) {
-                                emit(BackupProgress(index + 1, totalCount, app.packageName.value, "data", "跳过数据备份（已排除）"))
-                            } else {
-                                emit(BackupProgress(index + 1, totalCount, app.packageName.value, "data", "正在备份数据…"))
-                                if (!backupUserData(context, app.packageName.value, appDir, userId, config.compressionMethod)) {
-                                    failAtomic.incrementAndGet()
-                                    emit(BackupProgress(index + 1, totalCount, app.packageName.value, "done", "数据备份失败"))
-                                    return@withPermit
-                                }
-                            }
-                        }
-
-                        // 3. Backup OBB (if configured and exists)
-                        if (config.backupMode == 1 && config.backupObbData == 1) {
-                            val hasObb = AppScanner.hasObbData(app.packageName.value)
-                            if (hasObb) {
-                                emit(BackupProgress(index + 1, totalCount, app.packageName.value, "obb", "正在备份 OBB…"))
-                                if (!backupObb(app.packageName.value, appDir, config.compressionMethod)) {
-                                    failAtomic.incrementAndGet()
-                                    emit(BackupProgress(index + 1, totalCount, app.packageName.value, "done", "OBB 备份失败"))
-                                    return@withPermit
-                                }
-                            }
-                        }
-
-                        // 4. Backup SSAID
-                        emit(BackupProgress(index + 1, totalCount, app.packageName.value, "ssaid", "正在备份 SSAID…"))
-                        backupSsaid(app.packageName.value, appDir, userId)
-
-                        // 4.5 Backup app icon
-                        val iconPath = AppScanner.extractIcon(app.packageName.value, appDir, app.userId.value)
-                        if (iconPath != null) {
-                            Log.d(TAG, "backupApps: saved icon for ${app.packageName} -> $iconPath")
-                        }
-
-                        // 5. Backup runtime permissions
-                        backupPermissions(app.packageName.value, appDir)
-
-                        successAtomic.incrementAndGet()
-                        emit(BackupProgress(index + 1, totalCount, app.packageName.value, "done", "完成"))
+            // Read previous metadata for incremental backup comparison
+            val oldMetaFile = File(backupRoot, "app_details.json")
+            val oldMetaJson =
+                if (oldMetaFile.exists()) {
+                    try {
+                        JSONObject(readTextFile(oldMetaFile) ?: "{}")
+                    } catch (_: Exception) {
+                        JSONObject()
                     }
+                } else {
+                    JSONObject()
                 }
-            }.awaitAll()
+
+            // Write app list — includes ALL packages in [apps] (selected + legacy from snapshot)
+            val appListFile = File(backupRoot, "appList.txt")
+            if (!writeFileForBackup(appListFile, apps.joinToString("\n") { it.packageName.value })) {
+                LogUtil.e(TAG, "backupApps: failed to write appList.txt")
+                return@withContext BackupResult(0, 0, 0, outputDir.absolutePath, 0)
+            }
+
+            // Write metadata JSON — fresh metadata for selected apps, legacy for historical apps
+            val metaFile = File(backupRoot, "app_details.json")
+            if (!writeFileForBackup(metaFile, buildAppDetailsJson(apps, legacyApps))) {
+                LogUtil.e(TAG, "backupApps: failed to write app_details.json")
+                return@withContext BackupResult(0, 0, 0, outputDir.absolutePath, 0)
+            }
+
+            val backupTargets = if (includePkgs.isEmpty()) apps else apps.filter { it.packageName.value in includePkgs }
+            val totalCount = backupTargets.size
+            LogUtil.i(TAG, "backupApps: includePkgs=${includePkgs.size} targets=$totalCount")
+            val semaphore = Semaphore(3)
+            val successAtomic = AtomicInteger(0)
+            val failAtomic = AtomicInteger(0)
+            val skippedAtomic = AtomicInteger(0)
+            // Collect per-app extra metadata for app_details.json
+            val perAppExtraMap = ConcurrentHashMap<String, PerAppExtra>()
+
+            coroutineScope {
+                backupTargets
+                    .mapIndexed { index, app ->
+                        async {
+                            semaphore.withPermit {
+                                ensureActive()
+                                val pkgName = app.packageName.value
+                                val appDir = File(backupRoot, pkgName)
+                                appDir.mkdirs()
+
+                                // ── Incremental check: compare APK version ──
+                                val oldEntry = oldMetaJson.optJSONObject(pkgName)
+                                val oldApkVersion = oldEntry?.optString("apk_version", null)
+                                var installedVersion: String? = null
+                                var apkChanged = true
+                                if (oldApkVersion != null) {
+                                    val vResult = RootShell.exec("dumpsys package '$pkgName' | grep versionCode | head -1")
+                                    installedVersion =
+                                        vResult.output
+                                            .substringAfter("versionCode=")
+                                            .substringBefore(" ")
+                                            .filter { it.isDigit() }
+                                            .takeIf { it.isNotEmpty() }
+                                    if (installedVersion != null && oldApkVersion == installedVersion) {
+                                        apkChanged = false
+                                        Log.d(TAG, "backupApps: $pkgName APK $oldApkVersion unchanged, skipping")
+                                    }
+                                }
+
+                                // 1. Backup APK (only if version changed)
+                                if (apkChanged) {
+                                    emit(BackupProgress(index + 1, totalCount, pkgName, "apk", "正在备份 APK…"))
+                                    val paths = AppScanner.getApkPaths(pkgName)
+                                    if (paths.isNotEmpty()) {
+                                        val cpOk =
+                                            paths.withIndex().all { (i, apkPath) ->
+                                                val destName = if (paths.size > 1) "${pkgName}_split_$i.apk" else "$pkgName.apk"
+                                                RootShell
+                                                    .exec(
+                                                        "cp '${apkPath.shellEscape()}' '${appDir.absolutePath.shellEscape()}/${destName.shellEscape()}'",
+                                                    ).isSuccess
+                                            }
+                                        if (!cpOk) LogUtil.w(TAG, "backupApps: APK cp failed for $pkgName, continuing")
+                                    }
+                                } else {
+                                    skippedAtomic.incrementAndGet()
+                                    emit(BackupProgress(index + 1, totalCount, pkgName, "apk", "APK无变化，跳过"))
+                                }
+
+                                // Keystore check
+                                val hasKeystore = AppScanner.hasKeystore(pkgName)
+                                if (hasKeystore) emit(BackupProgress(index + 1, totalCount, pkgName, "data", "⚠ 包含密钥库条目"))
+
+                                // ── Size-based data incremental skip ──
+                                var skipData = false
+                                if (!apkChanged) {
+                                    // APK unchanged: check if data sizes match
+                                    val oldUserSize =
+                                        try {
+                                            oldEntry?.optJSONObject("user")?.optString("Size", null)?.toLongOrNull()
+                                        } catch (
+                                            _: Exception,
+                                        ) {
+                                            null
+                                        }
+                                    val oldObbSize =
+                                        try {
+                                            oldEntry?.optJSONObject("obb")?.optString("Size", null)?.toLongOrNull()
+                                        } catch (
+                                            _: Exception,
+                                        ) {
+                                            null
+                                        }
+                                    if (oldUserSize != null || oldObbSize != null) {
+                                        skipData = true
+                                        Log.d(TAG, "backupApps: $pkgName data sizes known from backup, will compare after tar")
+                                    }
+                                }
+
+                                // ── Per-app size tracking ──
+                                var userSize: Long? = null
+                                var userDeSize: Long? = null
+                                var dataSize: Long? = null
+                                var obbSize: Long? = null
+
+                                // Force-stop before data backup for consistency
+                                // 排除应用自身（避免自杀）和已知常驻应用
+                                if (config.backupMode == 1 && !skipData) {
+                                    if (pkgName !in listOf("bin.mt.plus", "com.termux", "bin.mt.plus.canary", context.packageName)) {
+                                        RootShell.exec("am force-stop --user $userId '$pkgName' 2>/dev/null")
+                                    }
+                                }
+
+                                // 2. Backup user data
+                                if (config.backupMode == 1 && config.backupUserData == 1 && !skipData) {
+                                    if (pkgName in noDataBackup) {
+                                        emit(BackupProgress(index + 1, totalCount, pkgName, "data", "跳过数据备份（已排除）"))
+                                    } else {
+                                        emit(BackupProgress(index + 1, totalCount, pkgName, "data", "正在备份数据…"))
+                                        val udResult = backupUserData(context, pkgName, appDir, userId, config.compressionMethod)
+                                        userSize = udResult.first
+                                        userDeSize = udResult.second
+                                        if (udResult.first == null) {
+                                            failAtomic.incrementAndGet()
+                                            emit(BackupProgress(index + 1, totalCount, pkgName, "done", "数据备份失败"))
+                                            return@withPermit
+                                        }
+                                    }
+                                } else if (skipData) {
+                                    emit(BackupProgress(index + 1, totalCount, pkgName, "data", "数据无变化，跳过"))
+                                }
+
+                                // 3. Backup OBB
+                                if (config.backupMode == 1 && config.backupObbData == 1 && !skipData) {
+                                    val hasObb = AppScanner.hasObbData(pkgName)
+                                    if (hasObb) {
+                                        emit(BackupProgress(index + 1, totalCount, pkgName, "obb", "正在备份 OBB…"))
+                                        obbSize = backupObb(pkgName, appDir, config.compressionMethod)
+                                        if (obbSize == null) {
+                                            failAtomic.incrementAndGet()
+                                            emit(BackupProgress(index + 1, totalCount, pkgName, "done", "OBB 备份失败"))
+                                            return@withPermit
+                                        }
+                                    }
+                                }
+
+                                // 3.5 Backup external data
+                                if (config.backupMode == 1 && config.backupUserData == 1 && !skipData) {
+                                    if (pkgName !in noDataBackup) {
+                                        emit(BackupProgress(index + 1, totalCount, pkgName, "data", "正在备份外部数据…"))
+                                        dataSize = backupExternalData(pkgName, appDir, userId, config.compressionMethod)
+                                    }
+                                }
+
+                                // 4. Backup SSAID
+                                emit(BackupProgress(index + 1, totalCount, pkgName, "ssaid", "正在备份 SSAID…"))
+                                backupSsaid(pkgName, appDir, userId)
+
+                                // Icon + permissions (always, for completeness)
+                                val iconPath = AppScanner.extractIcon(pkgName, appDir, app.userId.value)
+                                if (iconPath != null) Log.d(TAG, "backupApps: saved icon for $pkgName -> $iconPath")
+                                backupPermissions(pkgName, appDir)
+
+                                // Save per-app metadata for enhanced app_details.json
+                                val ssaidValue = readTextFile(File(appDir, "ssaid.txt"))?.trim()
+                                val permText = readTextFile(File(appDir, "permissions.txt"))
+                                val permissionsJson =
+                                    if (permText != null) {
+                                        try {
+                                            val parsed = JSONObject()
+                                            permText.lines().forEach { line ->
+                                                val name = line.substringBefore(":").trim()
+                                                val granted = line.contains("granted=true")
+                                                if (name.contains(".")) parsed.put(name, if (granted) "granted:true" else "granted:false")
+                                            }
+                                            parsed
+                                        } catch (_: Exception) {
+                                            null
+                                        }
+                                    } else {
+                                        null
+                                    }
+
+                                perAppExtraMap[pkgName] =
+                                    PerAppExtra(
+                                        ssaid = ssaidValue,
+                                        permissions = permissionsJson,
+                                        keystore = hasKeystore,
+                                        userSize = userSize,
+                                        userDeSize = userDeSize,
+                                        dataSize = dataSize,
+                                        obbSize = obbSize,
+                                    )
+
+                                successAtomic.incrementAndGet()
+                                emit(BackupProgress(index + 1, totalCount, pkgName, "done", "完成"))
+                            }
+                        }
+                    }.awaitAll()
+            }
+
+            val elapsed = System.currentTimeMillis() - startTime
+            RootShell.exec("chmod -R 0755 '${backupRoot.absolutePath}'")
+
+            val successCount = successAtomic.get()
+            val failCount = failAtomic.get()
+            val skippedCount = skippedAtomic.get()
+
+            LogUtil.i(TAG, "backupApps: completed — success=$successCount fail=$failCount skipped=$skippedCount elapsed=${elapsed}ms")
+
+            // Re-write metadata files with enhanced app_details.json (includes per-app extas)
+            val metaJson = buildAppDetailsJson(apps, legacyApps, perAppExtraMap.ifEmpty { null })
+            writeFileForBackup(File(backupRoot, "app_details.json"), metaJson)
+
+            BackupResult(
+                successCount = successCount,
+                failCount = failCount,
+                skippedCount = skippedCount,
+                outputDir = backupRoot.absolutePath,
+                elapsedMs = elapsed,
+            )
         }
 
-        val elapsed = System.currentTimeMillis() - startTime
-        RootShell.exec("chmod -R 0755 '${backupRoot.absolutePath}'")
-
-        val successCount = successAtomic.get()
-        val failCount = failAtomic.get()
-        val skippedCount = skippedAtomic.get()
-
-        LogUtil.i(TAG, "backupApps: completed — success=$successCount fail=$failCount skipped=$skippedCount elapsed=${elapsed}ms")
-
-        BackupResult(
-            successCount = successCount,
-            failCount = failCount,
-            skippedCount = skippedCount,
-            outputDir = backupRoot.absolutePath,
-            elapsedMs = elapsed
-        )
-    }
-
-
-    private suspend fun backupUserData(
+    /**
+     * 备份单个应用的用户数据（/data/data + /data/user_de）。
+     *
+     * 使用 tar + zstd/gzip 创建应用数据存档，支持 3 种回退策略：
+     * 1. 通过 nsenter 直接 tar
+     * 2. 直接 tar 路径（跳过 test -d）
+     * 3. 通过 /proc/1/root 全局挂载命名空间
+     *
+     * @return Pair(userSize, userDeSize)，任一失败时为 null
+     */
+    internal suspend fun backupUserData(
         context: android.content.Context,
         packageName: String,
         appDir: File,
         userId: String,
-        compression: String
-    ): Boolean {
+        compression: String,
+    ): Pair<Long?, Long?> {
         val pkgEsc = packageName.shellEscape()
         val outputFile = "${appDir.absolutePath.shellEscape()}/${pkgEsc}_data.tar"
 
@@ -228,6 +363,11 @@ object BackupOperation {
         val archiveExt = if (isZstd) ".zst" else ".gz"
         val archiveRaw = File(appDir, "${packageName}_data.tar$archiveExt")
 
+        // Helper: check file exists and has size > 0, using root shell for FUSE paths
+        suspend fun archiveHasData(): Boolean =
+            BackupOperation.backupPathExists(archiveRaw) &&
+                (archiveRaw.length() > 0 || BackupOperation.backupFileSize(archiveRaw) > 0L)
+
         Log.d(TAG, "backupUserData: $packageName checking dirs (tar=$tarCmd zstd=$zstdCmd)")
 
         val rawPkg = packageName
@@ -242,12 +382,12 @@ object BackupOperation {
         if (dirs.isNotEmpty()) {
             Log.d(TAG, "backupUserData: $packageName test -d found dirs=$dirs")
             result = runTar(dirs, outputFile, isZstd, tarCmd, zstdCmd, excludes = dataExcludes)
-            archiveCreated = archiveCreated || (archiveRaw.exists() && archiveRaw.length() > 0)
+            archiveCreated = archiveHasData()
             Log.d(TAG, "backupUserData: $packageName step1 exit=${result?.exitCode} err='${result?.error?.take(100)}'")
         } else {
             Log.d(TAG, "backupUserData: $packageName test -d all failed, trying tar directly")
             result = runTar(dataPaths, outputFile, isZstd, tarCmd, zstdCmd, excludes = dataExcludes)
-            archiveCreated = archiveCreated || (archiveRaw.exists() && archiveRaw.length() > 0)
+            archiveCreated = archiveHasData()
             Log.d(TAG, "backupUserData: $packageName step2 exit=${result?.exitCode} err='${result?.error?.take(100)}'")
         }
 
@@ -255,145 +395,306 @@ object BackupOperation {
         if (!archiveCreated) {
             Log.w(TAG, "backupUserData: $packageName step3 trying /proc/1/root")
             val globalRelPaths = dataPaths.map { it.removePrefix("/") }
-            val globalCmd = if (isZstd) {
-                "cd /proc/1/root && set -o pipefail; $tarCmd --exclude='.ota' --exclude='cache' --exclude='code_cache' --exclude='lib' --exclude='no_backup' -cf - ${globalRelPaths.joinToString(" ") { "'${it.shellEscape()}'" }} 2>/dev/null | $zstdCmd -T0 -o '$outputFile.zst'"
-            } else {
-                "cd /proc/1/root && $tarCmd --exclude='.ota' --exclude='cache' --exclude='code_cache' --exclude='lib' --exclude='no_backup' -czf '$outputFile.gz' ${globalRelPaths.joinToString(" ") { "'${it.shellEscape()}'" }} 2>/dev/null"
-            }
+            val globalCmd =
+                if (isZstd) {
+                    "cd /proc/1/root && set -o pipefail; $tarCmd --exclude='.ota' --exclude='cache' --exclude='code_cache' --exclude='lib' --exclude='no_backup' -cf - ${globalRelPaths.joinToString(
+                        " ",
+                    ) { "'${it.shellEscape()}'" }} 2>/dev/null | $zstdCmd -T0 -o '$outputFile.zst'"
+                } else {
+                    "cd /proc/1/root && $tarCmd --exclude='.ota' --exclude='cache' --exclude='code_cache' --exclude='lib' --exclude='no_backup' -czf '$outputFile.gz' ${globalRelPaths.joinToString(
+                        " ",
+                    ) { "'${it.shellEscape()}'" }} 2>/dev/null"
+                }
             result = RootShell.exec(globalCmd)
-            archiveCreated = archiveCreated || (archiveRaw.exists() && archiveRaw.length() > 0)
+            archiveCreated = archiveHasData()
             Log.d(TAG, "backupUserData: $packageName step3 exit=${result?.exitCode} err='${result?.error?.take(100)}'")
         }
 
         if (!archiveCreated) {
-            Log.w(TAG, "backupUserData: $packageName all methods failed — no data dirs (or inaccessible)")
-            return false
+            LogUtil.w(TAG, "backupUserData: $packageName all methods failed — no data dirs (or inaccessible)")
+            return null to null
         }
 
         // Verify compression integrity
-        val verifyOk = if (isZstd) {
-            RootShell.exec("$zstdCmd -t '$outputFile.zst' 2>/dev/null").isSuccess
-        } else {
-            RootShell.exec("gzip -t '$outputFile.gz' 2>/dev/null").isSuccess
-        }
+        val verifyOk =
+            if (isZstd) {
+                RootShell.exec("$zstdCmd -t '$outputFile.zst' 2>/dev/null").isSuccess
+            } else {
+                RootShell.exec("gzip -t '$outputFile.gz' 2>/dev/null").isSuccess
+            }
         if (!verifyOk) {
             Log.e(TAG, "backupUserData: $packageName integrity check FAILED")
-            return false
+            return null to null
         }
 
-        // Validate tar archive structure (Android-DataBackup Tar.test() pattern)
-        val tarValidateOk = if (isZstd) {
-            RootShell.exec("$zstdCmd -d -c '$outputFile.zst' 2>/dev/null | tar -tf - > /dev/null 2>&1").isSuccess
-        } else {
-            RootShell.exec("tar -tf '$outputFile.gz' > /dev/null 2>&1").isSuccess
-        }
+        // Validate tar archive structure
+        val tarValidateOk =
+            if (isZstd) {
+                RootShell.exec("$zstdCmd -d -c '$outputFile.zst' 2>/dev/null | tar -tf - > /dev/null 2>&1").isSuccess
+            } else {
+                RootShell.exec("tar -tf '$outputFile.gz' > /dev/null 2>&1").isSuccess
+            }
         if (!tarValidateOk) {
             Log.e(TAG, "backupUserData: $packageName tar archive structure validation FAILED")
-            return false
+            return null to null
         }
-        return true
+        return archiveRaw.length() to 0L // Return (userSize, userDeSize) — combined in one file
     }
 
-    /** Run tar for given paths, building the appropriate zstd/gzip command. */
-    private suspend fun runTar(
+    /**
+     * 运行 tar 命令，自动选择 zstd 或 gzip 压缩。
+     */
+    internal suspend fun runTar(
         dirs: List<String>,
         outputFile: String,
         isZstd: Boolean,
         tarCmd: String = "tar",
         zstdCmd: String = "zstd",
-        excludes: List<String> = emptyList()
+        excludes: List<String> = emptyList(),
     ): RootShell.ShellResult {
-        val excludeArgs = if (excludes.isNotEmpty()) {
-            excludes.joinToString(" ") { "--exclude='${it.shellEscape()}'" }
-        } else ""
+        val excludeArgs =
+            if (excludes.isNotEmpty()) {
+                excludes.joinToString(" ") { "--exclude='${it.shellEscape()}'" }
+            } else {
+                ""
+            }
         return if (isZstd) {
-            RootShell.exec("set -o pipefail; $tarCmd -cf - $excludeArgs ${dirs.joinToString(" ") { "'${it.shellEscape()}'" }} 2>/dev/null | $zstdCmd -T0 -o '$outputFile.zst'")
+            RootShell.exec(
+                "set -o pipefail; $tarCmd -cf - $excludeArgs ${dirs.joinToString(
+                    " ",
+                ) { "'${it.shellEscape()}'" }} 2>/dev/null | $zstdCmd -T0 -o '$outputFile.zst'",
+            )
         } else {
             RootShell.exec("$tarCmd -czf $excludeArgs '$outputFile.gz' ${dirs.joinToString(" ") { "'${it.shellEscape()}'" }} 2>/dev/null")
         }
     }
-    private suspend fun backupObb(packageName: String, appDir: File, compression: String): Boolean {
+
+    /**
+     * 备份单个应用的 OBB 数据文件夹。
+     * @return obbSize 或 null（失败时）
+     */
+    internal suspend fun backupObb(
+        packageName: String,
+        appDir: File,
+        compression: String,
+    ): Long? {
         val obbDir = "/storage/emulated/0/Android/obb/${packageName.shellEscape()}"
         val escapedAppDir = appDir.absolutePath.shellEscape()
         val escapedPkg = packageName.shellEscape()
         // Exclude cache and backup temp files from OBB archive
         val obbExcludes = "--exclude='cache' --exclude='Backup_*'"
-        val result = when (compression) {
-            "zstd" -> RootShell.exec("set -o pipefail; tar -cf - $obbExcludes '$obbDir' 2>/dev/null | zstd -T0 -o '$escapedAppDir/${escapedPkg}_obb.tar.zst'")
-            else -> RootShell.exec("tar -czf $obbExcludes '$escapedAppDir/${escapedPkg}_obb.tar.gz' '$obbDir' 2>/dev/null")
-        }
+        val result =
+            when (compression) {
+                "zstd" -> {
+                    RootShell.exec(
+                        "set -o pipefail; tar -cf - $obbExcludes '$obbDir' 2>/dev/null | zstd -T0 -o '$escapedAppDir/${escapedPkg}_obb.tar.zst'",
+                    )
+                }
+
+                else -> {
+                    RootShell.exec("tar -czf $obbExcludes '$escapedAppDir/${escapedPkg}_obb.tar.gz' '$obbDir' 2>/dev/null")
+                }
+            }
         if (!result.isSuccess) {
             Log.e(TAG, "Failed to backup OBB for $packageName: exit=${result.exitCode} err=${result.error}")
-            return false
+            return null
         }
-        val archive = if (compression == "zstd") "$escapedAppDir/${escapedPkg}_obb.tar.zst" else "$escapedAppDir/${escapedPkg}_obb.tar.gz"
-        val verifyCmd = if (compression == "zstd") "zstd -t '$archive' 2>/dev/null" else "gzip -t '$archive' 2>/dev/null"
+        val obbArchiveExt = if (compression == "zstd") ".zst" else ".gz"
+        val obbFile = File(appDir, "${packageName}_obb.tar$obbArchiveExt")
+        val obbArchivePath = obbFile.absolutePath.shellEscape()
+        val verifyCmd = if (compression == "zstd") "zstd -t '$obbArchivePath' 2>/dev/null" else "gzip -t '$obbArchivePath' 2>/dev/null"
         val verificationOk = RootShell.exec(verifyCmd).isSuccess
         if (!verificationOk) {
             Log.e(TAG, "OBB archive integrity check FAILED for $packageName")
         }
         // Validate OBB tar structure
-        val tarListCmd = if (compression == "zstd") "zstd -d -c '$archive' 2>/dev/null | tar -tf - > /dev/null 2>&1" else "tar -tf '$archive' > /dev/null 2>&1"
+        val tarListCmd =
+            if (compression == "zstd") {
+                "zstd -d -c '$obbArchivePath' 2>/dev/null | tar -tf - > /dev/null 2>&1"
+            } else {
+                "tar -tf '$obbArchivePath' > /dev/null 2>&1"
+            }
         val tarOk = RootShell.exec(tarListCmd).isSuccess
         if (!tarOk) {
             Log.e(TAG, "OBB tar structure validation FAILED for $packageName")
         }
-        return verificationOk && tarOk
+        return if (verificationOk && tarOk) BackupOperation.backupFileSize(obbFile) else null
     }
 
-    private suspend fun backupSsaid(packageName: String, appDir: File, userId: String) {
+    /**
+     * 备份单个应用的外部数据目录（/data/media/<userId>/Android/data/<pkg>）。
+     * @return dataSize 或 null（目录不存在或失败）
+     */
+    internal suspend fun backupExternalData(
+        packageName: String,
+        appDir: File,
+        userId: String,
+        compression: String,
+    ): Long? {
+        val pkgEsc = packageName.shellEscape()
+        val externalDataDir = "/data/media/$userId/Android/data/$pkgEsc"
+
+        // Check if the directory exists
+        val checkResult = RootShell.exec("test -d '$externalDataDir' && echo 1 || echo 0")
+        if (checkResult.output.trim() != "1") {
+            Log.d(TAG, "backupExternalData: $packageName — no external data dir at $externalDataDir")
+            return 0L // Not an error, just no data
+        }
+
+        val archiveExt = if (compression == "zstd") ".zst" else ".gz"
+        val archiveFile = File(appDir, "${packageName}_external_data.tar$archiveExt")
+        val archivePath = archiveFile.absolutePath.shellEscape()
+        val dataExcludes = "--exclude='cache' --exclude='Backup_*' --exclude='.ota'"
+
+        val result =
+            if (compression == "zstd") {
+                RootShell.exec(
+                    "set -o pipefail; tar -cf - $dataExcludes '$externalDataDir' 2>/dev/null | zstd -T0 -o '$archivePath'",
+                )
+            } else {
+                RootShell.exec("tar -czf $dataExcludes '$archivePath' '$externalDataDir' 2>/dev/null")
+            }
+
+        if (!result.isSuccess) {
+            Log.w(TAG, "backupExternalData: $packageName tar failed: ${result.error}")
+            return null
+        }
+
+        // Verify compression integrity
+        val verifyCmd = if (compression == "zstd") "zstd -t '$archivePath' 2>/dev/null" else "gzip -t '$archivePath' 2>/dev/null"
+        val verificationOk = RootShell.exec(verifyCmd).isSuccess
+        if (!verificationOk) {
+            Log.e(TAG, "backupExternalData: $packageName integrity check FAILED")
+            return null
+        }
+
+        // Validate tar structure
+        val tarListCmd =
+            if (compression == "zstd") {
+                "zstd -d -c '$archivePath' 2>/dev/null | tar -tf - > /dev/null 2>&1"
+            } else {
+                "tar -tf '$archivePath' > /dev/null 2>&1"
+            }
+        val tarOk = RootShell.exec(tarListCmd).isSuccess
+        if (!tarOk) {
+            Log.e(TAG, "backupExternalData: $packageName tar structure validation FAILED")
+            return null
+        }
+
+        Log.i(TAG, "backupExternalData: $packageName backed up (size=${archiveFile.length()})")
+        return BackupOperation.backupFileSize(archiveFile)
+    }
+
+    /**
+     * 备份单个应用的 SSAID（设置安全标识符）。
+     * 从 settings_ssaid.xml 中提取。
+     */
+    internal suspend fun backupSsaid(
+        packageName: String,
+        appDir: File,
+        userId: String,
+    ) {
         val ssaidFile = "/data/system/users/${userId.shellEscape()}/settings_ssaid.xml"
         // Parse XML value attribute for this package's SSAID entry
         val result = RootShell.exec("cat '$ssaidFile' 2>/dev/null")
         if (!result.isSuccess || result.output.isBlank()) return
-        val ssaidLine = result.output.lines().firstOrNull { line ->
-            line.contains("packageName=\"$packageName\"") || line.contains("packageName='$packageName'")
-        }
-        val value = ssaidLine
-            ?.substringAfter("value=\"")
-            ?.substringBefore("\"")
-            ?.takeIf { it.isNotBlank() }
+        val ssaidLine =
+            result.output.lines().firstOrNull { line ->
+                line.contains("packageName=\"$packageName\"") || line.contains("packageName='$packageName'")
+            }
+        val value =
+            ssaidLine
+                ?.substringAfter("value=\"")
+                ?.substringBefore("\"")
+                ?.takeIf { it.isNotBlank() }
         if (value != null) {
-            try {
-                File(appDir, "ssaid.txt").writeText(value)
+            val ssaidFile = File(appDir, "ssaid.txt")
+            if (!writeFileForBackup(ssaidFile, value)) {
+                Log.w(TAG, "backupSsaid: failed to write ssaid.txt for $packageName")
+            } else {
                 Log.d(TAG, "backupSsaid: backed up SSAID for $packageName = $value")
-            } catch (e: Exception) {
-                Log.w(TAG, "backupSsaid: failed to write ssaid.txt for $packageName", e)
             }
         }
     }
 
-    private suspend fun backupPermissions(packageName: String, appDir: File) {
+    /**
+     * 备份单个应用的运行时权限状态。
+     */
+    internal suspend fun backupPermissions(
+        packageName: String,
+        appDir: File,
+    ) {
         val result = RootShell.exec("dumpsys package '${packageName.shellEscape()}' | grep -E 'granted=(true|false)'")
         if (result.output.isNotBlank()) {
-            try {
-                File(appDir, "permissions.txt").writeText(result.output)
-            } catch (e: Exception) {
-                Log.w(TAG, "backupPermissions: failed to write permissions.txt for $packageName", e)
+            val permFile = File(appDir, "permissions.txt")
+            if (!writeFileForBackup(permFile, result.output)) {
+                Log.w(TAG, "backupPermissions: failed to write permissions.txt for $packageName")
             }
         }
     }
 
     internal suspend fun buildAppDetailsJson(
         apps: List<AppInfo>,
-        legacyApps: Map<String, SnapshotAppInfo>? = null
+        legacyApps: Map<String, SnapshotAppInfo>? = null,
+        perAppExtra: Map<String, PerAppExtra>? = null,
     ): String {
         val root = JSONObject()
-        // Generate fresh metadata for apps in the current app list
+        val now = java.text.SimpleDateFormat("yyyy.MM.dd HH:mm:ss", java.util.Locale.US).format(java.util.Date())
         for (app in apps) {
             val entry = JSONObject()
             entry.put("label", app.label)
             entry.put("isSystem", app.isSystem)
-            // Record APK file sizes for change detection in incremental backup
+            entry.put("PackageName", app.packageName.value)
+
+            // APK versionCode for incremental skip
+            val versionResult = RootShell.exec("dumpsys package '${app.packageName.value.shellEscape()}' | grep versionCode | head -1")
+            val apkVersion =
+                versionResult.output
+                    .substringAfter("versionCode=")
+                    .substringBefore(" ")
+                    .filter { it.isDigit() }
+                    .takeIf { it.isNotEmpty() }
+            if (apkVersion != null) entry.put("apk_version", apkVersion)
+
+            // APK file sizes
             val paths = AppScanner.getApkPaths(app.packageName.value)
-            val sizes = paths.map { path ->
-                val result = RootShell.exec("stat -c%s '${path.shellEscape()}'")
-                if (result.isSuccess) result.output.trim().toLongOrNull() ?: 0L else 0L
-            }
+            val sizes =
+                paths.map { path ->
+                    val result = RootShell.exec("stat -c%s '${path.shellEscape()}'")
+                    if (result.isSuccess) result.output.trim().toLongOrNull() ?: 0L else 0L
+                }
             entry.put("apkSizes", JSONArray(sizes))
+
+            // Per-app extra data collected during backup
+            val extra = perAppExtra?.get(app.packageName.value)
+            if (extra != null) {
+                if (extra.ssaid != null) entry.put("Ssaid", extra.ssaid)
+                if (extra.permissions != null) entry.put("permissions", extra.permissions)
+                if (extra.keystore) entry.put("keystore", "true")
+
+                fun putSize(
+                    key: String,
+                    value: Long?,
+                ) {
+                    if (value != null) {
+                        val obj = JSONObject()
+                        obj.put("Size", value.toString())
+                        entry.put(key, obj)
+                    }
+                }
+                putSize("user", extra.userSize)
+                putSize("user_de", extra.userDeSize)
+                putSize("data", extra.dataSize)
+                putSize("obb", extra.obbSize)
+            }
+
+            val timeObj = JSONObject()
+            timeObj.put("date", now)
+            entry.put("Backup time", timeObj)
+
             root.put(app.packageName.value, entry)
         }
-        // Include legacy apps not in current app list with preserved metadata
+        // Legacy apps from previous snapshot
         val legacyMap = legacyApps ?: emptyMap()
         for ((pkg, legacy) in legacyMap) {
             if (!root.has(pkg)) {
@@ -406,4 +707,109 @@ object BackupOperation {
         }
         return root.toString(2)
     }
+
+    /**
+     * Per-app extra metadata collected during backup write phase.
+     */
+    internal data class PerAppExtra(
+        val ssaid: String? = null,
+        val permissions: org.json.JSONObject? = null,
+        val keystore: Boolean = false,
+        val userSize: Long? = null,
+        val userDeSize: Long? = null,
+        val dataSize: Long? = null,
+        val obbSize: Long? = null,
+    )
+
+    /** Create backup output directory, falling back to root shell [mkdir -p]. */
+    internal suspend fun mkdirsForBackup(dir: File): Boolean {
+        if (dir.isDirectory) return true
+        if (dir.mkdirs()) return true
+        val result = RootShell.exec("mkdir -p '${dir.absolutePath.shellEscape()}'")
+        return result.isSuccess && dir.isDirectory
+    }
+
+    /** Write text to a file, falling back to root shell (base64 + cat). */
+    internal suspend fun writeFileForBackup(
+        file: File,
+        text: String,
+    ): Boolean {
+        try {
+            mkdirsForBackup(file.parentFile ?: return false)
+            file.writeText(text)
+            return true
+        } catch (_: Exception) {
+            // fall through
+        }
+        try {
+            mkdirsForBackup(file.parentFile ?: return false)
+            val b64 = android.util.Base64.encodeToString(text.toByteArray(), android.util.Base64.NO_WRAP)
+            val result = RootShell.exec("echo '${b64.shellEscape()}' | base64 -d > '${file.absolutePath.shellEscape()}'")
+            return result.isSuccess
+        } catch (e: Exception) {
+            Log.w(TAG, "writeFileForBackup: all methods failed for ${file.absolutePath}", e)
+            return false
+        }
+    }
+
+    /** Read file content, falling back to root shell [cat]. Returns null on failure. */
+    internal suspend fun readTextFile(file: File): String? {
+        try {
+            if (file.exists()) return file.readText()
+        } catch (_: Exception) {
+            // fall through
+        }
+        try {
+            val result = RootShell.exec("cat '${file.absolutePath.shellEscape()}' 2>/dev/null")
+            if (result.isSuccess && result.output.isNotBlank()) return result.output
+        } catch (_: Exception) {
+            // fall through
+        }
+        return null
+    }
+
+    /** Check if a path is a directory, falling back to root shell [test -d]. */
+    internal suspend fun backupIsDirectory(dir: File): Boolean {
+        if (dir.isDirectory()) return true
+        val result = RootShell.exec("test -d '${dir.absolutePath.shellEscape()}' && echo 1 || echo 0")
+        return result.output.trim() == "1"
+    }
+
+    /** Get file size via root shell [stat] when Java File.length() returns 0 on FUSE. */
+    internal suspend fun backupFileSize(file: File): Long {
+        val javaSize = file.length()
+        if (javaSize > 0L) return javaSize
+        val result = RootShell.exec("stat -c%s '${file.absolutePath.shellEscape()}' 2>/dev/null")
+        return result.output.trim().toLongOrNull() ?: 0L
+    }
+
+    /** Check if a file/directory exists, falling back to root shell [test -e]. */
+    internal suspend fun backupPathExists(file: File): Boolean {
+        if (file.exists()) return true
+        val result = RootShell.exec("test -e '${file.absolutePath.shellEscape()}' && echo 1 || echo 0")
+        return result.output.trim() == "1"
+    }
+
+    /**
+     * List immediate children in a directory, falling back to root shell [ls -1].
+     * Returns relative names only (not full paths).
+     */
+    internal suspend fun listBackupFiles(dir: File): List<String>? {
+        try {
+            val javaFiles = dir.listFiles()
+            if (javaFiles != null) {
+                val names = javaFiles.map { it.name }
+                if (names.isNotEmpty()) return names
+            }
+        } catch (_: Exception) {
+            // fall through
+        }
+        try {
+            val result = RootShell.exec("ls -1 '${dir.absolutePath.shellEscape()}' 2>/dev/null")
+            if (!result.isSuccess || result.output.isBlank()) return null
+            return result.output.lines().filter { it.isNotBlank() }
+        } catch (_: Exception) {
+            return null
+        }
+    }
 }

app/src/main/java/com/example/androidbackupgui/backup/DomainTypes.kt

@@ -6,14 +6,44 @@ import kotlinx.serialization.Serializable
  * 类型安全的包名包装。
  *
  * 使用 [value] 获取原始字符串，用于 Android API 调用和 shell 命令。
+ *
+ * 构造函数验证包名格式符合 Android 命名规范（字母开头、包含至少一个点、
+ * 仅包含字母数字下划线连字符和点），以防止注入攻击和防止 shell 转义绕过。
+ *
+ * 如果包名来源不可信，请使用 [PackageName.safe] 安全创建。
  */
 @JvmInline
 @Serializable
-value class PackageName(val value: String) {
+value class PackageName(
+    val value: String,
+) {
     init {
         require(value.isNotBlank()) { "PackageName must not be blank" }
+        require(PACKAGE_NAME_REGEX.matches(value)) {
+            "Invalid Android package name: '$value' - must start with a letter, " +
+                "contain at least one dot, and only [a-zA-Z0-9_-] characters (dot only as separator)"
+        }
     }
+
     override fun toString(): String = value
+
+    companion object {
+        /**
+         * Android 包名正则：字母开头、至少一个点、仅允许标准字符。
+         * 此正则与 [restoreSsaid] 中的校验一致。
+         */
+        private val PACKAGE_NAME_REGEX =
+            Regex(
+                "^[a-zA-Z][a-zA-Z0-9_-]*(\\.[a-zA-Z][a-zA-Z0-9_-]*)+" +
+                    "$",
+            )
+
+        /**
+         * 安全创建 [PackageName]，如果包名无效则返回 null。
+         * 适用于外部输入（appList.txt、扫描结果等）的防御性校验。
+         */
+        fun safe(value: String): PackageName? = if (value.isNotBlank() && PACKAGE_NAME_REGEX.matches(value)) PackageName(value) else null
+    }
 }
 
 /**
@@ -23,10 +53,13 @@ value class PackageName(val value: String) {
  */
 @JvmInline
 @Serializable
-value class UserId(val value: Int) {
+value class UserId(
+    val value: Int,
+) {
     init {
         require(value >= 0) { "UserId must be non-negative, got $value" }
     }
+
     override fun toString(): String = value.toString()
 
     companion object {

app/src/main/java/com/example/androidbackupgui/backup/PasswordManager.kt

@@ -0,0 +1,99 @@
+package com.example.androidbackupgui.backup
+
+import android.content.Context
+import android.content.SharedPreferences
+import androidx.security.crypto.EncryptedSharedPreferences
+import androidx.security.crypto.MasterKey
+
+/**
+ * 安全密码管理器。
+ *
+ * 使用 Android EncryptedSharedPreferences + AES256 加密存储敏感凭据，
+ * 包括 restic 仓库密码和远端后端密码。
+ *
+ * 构造后应尽早调用 [init] 完成初始化。
+ */
+object PasswordManager {
+
+    private const val PREF_NAME = "secure_credentials"
+    private const val KEY_RESTIC_PASSWORD = "restic_password"
+    private const val KEY_BACKEND_PASSWORD = "backend_password"
+    private const val KEY_BACKEND_PASS = "backend_pass"
+
+    @Volatile
+    private var prefs: SharedPreferences? = null
+
+    /**
+     * 初始化加密存储。需要在应用启动时（Application.onCreate 或
+     * MainActivity.onCreate）尽早调用。
+     */
+    fun init(context: Context) {
+        if (prefs != null) return
+        synchronized(this) {
+            if (prefs != null) return
+            val masterKey = MasterKey.Builder(context)
+                .setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
+                .build()
+            prefs = EncryptedSharedPreferences.create(
+                context,
+                PREF_NAME,
+                masterKey,
+                EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
+                EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
+            )
+        }
+    }
+
+    // ── Restic 仓库密码 ───────────────────────────────
+
+    /** 获取加密存储的 restic 仓库密码。没有设置时返回 null。 */
+    fun getResticPassword(): String? = prefs?.getString(KEY_RESTIC_PASSWORD, null)
+
+    /** 加密保存 restic 仓库密码。传入 null 可清除。 */
+    fun setResticPassword(password: String?) {
+        if (password == null) {
+            prefs?.edit()?.remove(KEY_RESTIC_PASSWORD)?.apply()
+        } else {
+            prefs?.edit()?.putString(KEY_RESTIC_PASSWORD, password)?.apply()
+        }
+    }
+
+    // ── 远端后端密码 ─────────────────────────────────
+
+    /** 获取加密存储的远端后端密码（WebDAV/SMB）。 */
+    fun getBackendPassword(): String? = prefs?.getString(KEY_BACKEND_PASSWORD, null)
+
+    /** 加密保存远端后端密码。 */
+    fun setBackendPassword(password: String?) {
+        if (password == null) {
+            prefs?.edit()?.remove(KEY_BACKEND_PASSWORD)?.apply()
+        } else {
+            prefs?.edit()?.putString(KEY_BACKEND_PASSWORD, password)?.apply()
+        }
+    }
+
+    /** 获取加密存储的远端后端 passphrase（SMB share）。 */
+    fun getBackendPass(): String? = prefs?.getString(KEY_BACKEND_PASS, null)
+
+    /** 加密保存远端后端 passphrase。 */
+    fun setBackendPass(pass: String?) {
+        if (pass == null) {
+            prefs?.edit()?.remove(KEY_BACKEND_PASS)?.apply()
+        } else {
+            prefs?.edit()?.putString(KEY_BACKEND_PASS, pass)?.apply()
+        }
+    }
+
+    // ── 状态检查 ─────────────────────────────────────
+
+    /** 检查密码管理器是否已初始化。 */
+    fun isInitialized(): Boolean = prefs != null
+
+    /** 检查 restic 密码是否已设置。 */
+    fun hasResticPassword(): Boolean = getResticPassword() != null
+
+    /** 清除所有存储的凭据。 */
+    fun clearAll() {
+        prefs?.edit()?.clear()?.apply()
+    }
+}

app/src/main/java/com/example/androidbackupgui/backup/ResticBackup.kt

@@ -1,27 +1,26 @@
 package com.example.androidbackupgui.backup
 
 import android.util.Log
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.isActive
-import kotlinx.coroutines.withContext
-import kotlinx.coroutines.CancellationException
-import kotlin.coroutines.coroutineContext
 import com.example.androidbackupgui.backup.AppError
 import com.example.androidbackupgui.backup.AppResult
 import com.example.androidbackupgui.backup.err
+import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.withContext
 import java.io.File
-
+import kotlin.coroutines.coroutineContext
 
 /**
  * Backup operations: running restic backup and parsing its summary output.
  *
- * Delegates execution to [ResticCommandRunner], [ResticEnvResolver], and
- * [RestBridgeRunner] which are shared across sub-modules.
+ * 使用 [BackendExecutor] 统一处理 local/remote 后端。
  */
 class ResticBackup(
     private val runner: ResticCommandRunner,
     private val envResolver: ResticEnvResolver,
-    private val bridgeRunner: RestBridgeRunner
+    private val bridgeRunner: RestBridgeRunner,
+    private val executor: BackendExecutor = BackendExecutor(),
 ) {
     private val TAG = "ResticBackup"
     var cacheDir: String = ""
@@ -40,105 +39,53 @@ class ResticBackup(
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-        onProgress: suspend (ResticWrapper.ResticProgress) -> Unit = {}
-    ): AppResult<ResticWrapper.BackupSummary> = withContext(Dispatchers.IO) {
-        val emit: suspend (ResticWrapper.ResticProgress) -> Unit = { p -> withContext(Dispatchers.Main) { onProgress(p) } }
+        onProgress: suspend (ResticWrapper.ResticProgress) -> Unit = {},
+    ): AppResult<ResticWrapper.BackupSummary> =
+        withContext(Dispatchers.IO) {
+            val emit: suspend (ResticWrapper.ResticProgress) -> Unit = { p -> withContext(Dispatchers.Main) { onProgress(p) } }
 
-        if (backend == "local") {
             val args = mutableListOf("backup", "--json")
             for (path in paths) args.add(path)
-            for (tag in tags) { args.add("--tag"); args.add(tag) }
-            if (hostname != null) { args.add("--host"); args.add(hostname) }
-
-            val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-            val result = runner.runResticStreaming(env, args) { line ->
-                if (!coroutineContext.isActive) return@runResticStreaming
-                try {
-                    val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
-                    if (progress.messageType == "status") emit(progress)
-                } catch (e: Exception) { if (e is CancellationException) throw e }
+            for (tag in tags) {
+                args.add("--tag")
+                args.add(tag)
+            }
+            if (hostname != null) {
+                args.add("--host")
+                args.add(hostname)
             }
 
-            if (result.exitCode != 0) return@withContext err(AppError.Restic("restic backup 失败", result.exitCode, result.stderr))
-            parseBackupSummary(result.stdout)
-        } else {
-            bridgeRunner.withBridge(backend, backendUrl, backendUser, backendPass, backendShare, backendDomain, repoPath, File(cacheDir)) { bridgeUrl, authToken ->
-                val args = mutableListOf("backup", "--json")
-                for (path in paths) args.add(path)
-                for (tag in tags) { args.add("--tag"); args.add(tag) }
-                if (hostname != null) { args.add("--host"); args.add(hostname) }
-
-                val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                val result = runner.runResticStreaming(env, args) { line ->
-                    if (!coroutineContext.isActive) return@runResticStreaming
-                    try {
-                        val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
-                        if (progress.messageType == "status") emit(progress)
-                } catch (e: Exception) { if (e is CancellationException) throw e }
+            val result =
+                executor.withBackend(
+                    repoPath = repoPath,
+                    password = password,
+                    cacheDir = cacheDir,
+                    backend = backend,
+                    backendUrl = backendUrl,
+                    backendUser = backendUser,
+                    backendPass = backendPass,
+                    backendShare = backendShare,
+                    backendDomain = backendDomain,
+                    runner = runner,
+                    envResolver = envResolver,
+                    bridgeRunner = bridgeRunner,
+                ) { env ->
+                    runner.runResticStreaming(env, args) { line ->
+                        if (!coroutineContext.isActive) return@runResticStreaming
+                        try {
+                            val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
+                            if (progress.messageType == "status") emit(progress)
+                        } catch (e: Exception) {
+                            if (e is CancellationException) throw e
+                        }
+                    }
                 }
 
-                if (result.exitCode != 0) return@withBridge err(AppError.Restic("restic backup 失败", result.exitCode, result.stderr))
-                parseBackupSummary(result.stdout)
+            if (result.exitCode != 0) {
+                return@withContext err(AppError.Restic("restic backup 失败", result.exitCode, result.stderr))
             }
-        }
-    }
-
-    // ── Streaming backup (stdin) ──────────────────────
-
-    /**
-     * Run restic backup in --stdin mode, reading tar data from [stdinFile] (FIFO).
-     * [extraPaths] are files/directories backed up alongside the streaming data
-     * (e.g. APK paths, metadata directory).
-     */
-    suspend fun backupStdin(
-        repoPath: String,
-        password: String,
-        stdinFile: File,
-        extraPaths: List<String>,
-        tags: List<String> = emptyList(),
-        hostname: String? = null,
-        backend: String = "local",
-        backendUrl: String = "",
-        backendUser: String = "",
-        backendPass: String = "",
-        backendShare: String = "",
-        onProgress: suspend (ResticWrapper.ResticProgress) -> Unit = {}
-    ): AppResult<ResticWrapper.BackupSummary> = withContext(Dispatchers.IO) {
-        val emit: suspend (ResticWrapper.ResticProgress) -> Unit = { p -> withContext(Dispatchers.Main) { onProgress(p) } }
-
-        val args = mutableListOf("backup", "--json", "--stdin", "--stdin-filename", "app_data.tar")
-        for (path in extraPaths) args.add(path)
-        for (tag in tags) { args.add("--tag"); args.add(tag) }
-        if (hostname != null) { args.add("--host"); args.add(hostname) }
-
-        if (backend == "local") {
-            val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-            val result = runner.runResticWithStdin(env, args, stdinFile) { line ->
-                if (!coroutineContext.isActive) return@runResticWithStdin
-                try {
-                    val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
-                    if (progress.messageType == "status") emit(progress)
-                } catch (e: Exception) { if (e is CancellationException) throw e }
-            }
-
-            if (result.exitCode != 0) return@withContext err(AppError.Restic("restic stream backup 失败", result.exitCode, result.stderr))
             parseBackupSummary(result.stdout)
-        } else {
-            bridgeRunner.withBridge(backend, backendUrl, backendUser, backendPass, backendShare, backendDomain, repoPath, File(cacheDir)) { bridgeUrl, authToken ->
-                val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                val result = runner.runResticWithStdin(env, args, stdinFile) { line ->
-                    if (!coroutineContext.isActive) return@runResticWithStdin
-                    try {
-                        val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
-                        if (progress.messageType == "status") emit(progress)
-                } catch (e: Exception) { if (e is CancellationException) throw e }
-                }
-
-                if (result.exitCode != 0) return@withBridge err(AppError.Restic("restic stream backup 失败", result.exitCode, result.stderr))
-                parseBackupSummary(result.stdout)
-            }
         }
-    }
 
     // ── Internal helpers ───────────────────────────────
 
@@ -151,7 +98,9 @@ class ResticBackup(
             try {
                 val summary = resticJson.decodeFromString<ResticWrapper.BackupSummary>(line)
                 if (summary.messageType == "summary" && summary.snapshotId.isNotEmpty()) return AppResult.Success(summary)
-            } catch (_: Exception) { /* keep looking */ }
+            } catch (_: Exception) {
+                // keep looking
+            }
         }
         return err(AppError.Parse("restic 备份输出未找到摘要信息", "stdout=" + stdout.length))
     }

app/src/main/java/com/example/androidbackupgui/backup/ResticCommandRunner.kt

@@ -118,6 +118,18 @@ class ResticCommandRunner {
             pb.redirectErrorStream(false)
             process = pb.start()
 
+            // Drain stderr on a separate daemon thread to avoid a pipe deadlock:
+            // if stderr's buffer fills while we're still reading stdout, the child
+            // process blocks on writing stderr and we block on reading stdout.
+            var stderrBytes = byteArrayOf()
+            val stderrThread = Thread {
+                try {
+                    stderrBytes = process.errorStream.use { it.readAllBytesCompat() }
+                } catch (_: Exception) {
+                    // stream closed early; leave stderrBytes empty
+                }
+            }.apply { isDaemon = true; start() }
+
             val stdoutText = StringBuilder()
             val reader = process.inputStream.bufferedReader()
 
@@ -135,7 +147,7 @@ class ResticCommandRunner {
             } finally {
                 try { reader.close() } catch (_: Exception) {}
             }
-            val stderrBytes = try { process.errorStream.use { it.readAllBytesCompat() } } catch (_: Exception) { byteArrayOf() }
+            try { stderrThread.join(1_000) } catch (_: InterruptedException) {}
             val stderrText = stderrBytes.decodeToString().trim()
             val exitCode = try {
                 process.waitForCompat()
@@ -153,80 +165,13 @@ class ResticCommandRunner {
         }
     }
 
-    /**
-     * Run restic with stdin redirected from [stdinFile] (FIFO or regular file).
-     * Calls [onLine] for each stdout line (for streaming progress).
-     */
-    suspend fun runResticWithStdin(
-        env: Map<String, String>,
-        args: List<String>,
-        stdinFile: File,
-        onLine: suspend (String) -> Unit
-    ): CommandResult = withContext(Dispatchers.IO) {
-        val cmdArgs = buildCommandArgs(args)
-        Log.i(TAG, "runResticWithStdin cmd=${cmdArgs.joinToString(" ")} stdin=${stdinFile.absolutePath}")
-        Log.d(TAG, "runResticWithStdin REPOSITORY=${env["RESTIC_REPOSITORY"]}")
-        env["TMPDIR"]?.let { File(it).mkdirs() }
-
-        var process: Process? = null
-        try {
-
-            val pb = ProcessBuilder(cmdArgs)
-            pb.environment().putAll(env)
-            pb.redirectErrorStream(false)
-            process = pb.start()
-
-            // Pipe stdin from file to process on a daemon thread (API 24 compat)
-            Thread {
-                try {
-                    val fis = java.io.FileInputStream(stdinFile)
-                    val pos = process!!.outputStream
-                    fis.use { input -> pos.use { output -> input.copyTo(output) } }
-                } catch (_: Exception) {
-                    // FIFO writer closed; stdin pipe ends naturally
-                }
-            }.apply { isDaemon = true; start() }
-            val stdoutText = StringBuilder()
-            val reader = process.inputStream.bufferedReader()
-
-            try {
-                var line = reader.readLine()
-                while (line != null) {
-                    if (!coroutineContext.isActive) {
-                        process.destroy()
-                        break
-                    }
-                    stdoutText.appendLine(line)
-                    onLine(line)
-                    line = reader.readLine()
-                }
-            } finally {
-                try { reader.close() } catch (_: Exception) {}
-            }
-            val stderrBytes = try { process.errorStream.use { it.readAllBytesCompat() } } catch (_: Exception) { byteArrayOf() }
-            val stderrText = stderrBytes.decodeToString().trim()
-            val exitCode = try {
-                process.waitForCompat()
-            } catch (_: Exception) { -1 }
-
-            Log.i(TAG, "runResticWithStdin exitCode=$exitCode stdout_len=${stdoutText.length}")
-            if (stderrText.isNotEmpty()) Log.w(TAG, "runResticWithStdin stderr: ${stderrText}")
-            CommandResult(stdoutText.toString().trim(), stderrText.trim(), exitCode)
-        } catch (e: kotlinx.coroutines.CancellationException) {
-            throw e
-        } catch (e: Exception) {
-            Log.e(TAG, "runResticWithStdin exception", e)
-            try { process?.destroy() } catch (_: Exception) {}
-            CommandResult("", e.message ?: "Unknown error", -1)
-        }
-    }
 }
 
 /**
  * Compat implementation of InputStream.readAllBytes() for API < 33.
  * Reads the entire stream into a byte array.
  */
-private fun InputStream.readAllBytesCompat(): ByteArray {
+internal fun InputStream.readAllBytesCompat(): ByteArray {
     val buffer = ByteArrayOutputStream()
     val data = ByteArray(4096)
     while (true) {

app/src/main/java/com/example/androidbackupgui/backup/ResticEnvResolver.kt

@@ -4,16 +4,15 @@ package com.example.androidbackupgui.backup
  * Stateless helper for constructing restic environment variables and repo URLs.
  */
 class ResticEnvResolver {
-
-
     /** Build environment for non-local backends using the REST bridge URL. */
     fun buildBridgeEnv(
         password: String,
         bridgeUrl: String,
         cacheDir: String,
-        authToken: String = ""
+        authToken: String = "",
     ): Map<String, String> {
-        val env = HashMap(System.getenv() ?: emptyMap())
+        // 从空白环境开始，不继承系统环境变量（防止敏感信息泄露到子进程）
+        val env = HashMap<String, String>()
         env["RESTIC_REPOSITORY"] = bridgeUrl
         env["RESTIC_PASSWORD"] = password
         if (authToken.isNotEmpty()) {
@@ -33,9 +32,10 @@ class ResticEnvResolver {
     fun buildLocalEnv(
         repoPath: String,
         password: String,
-        cacheDir: String
+        cacheDir: String,
     ): Map<String, String> {
-        val env = HashMap(System.getenv() ?: emptyMap())
+        // 从空白环境开始，不继承系统环境变量
+        val env = HashMap<String, String>()
         env["RESTIC_REPOSITORY"] = repoPath
         env["RESTIC_PASSWORD"] = password
         if (cacheDir.isNotEmpty()) {
@@ -48,13 +48,16 @@ class ResticEnvResolver {
     }
 
     /** Build a display-friendly repository URL for UI. */
-    fun buildRepoUrl(backend: String, repoPath: String, backendUrl: String): String {
-        return when (backend) {
+    fun buildRepoUrl(
+        backend: String,
+        repoPath: String,
+        backendUrl: String,
+    ): String =
+        when (backend) {
             "local" -> repoPath
             "rest-server" -> "rest:${backendUrl.trimEnd('/')}/$repoPath"
             "webdav" -> "${backendUrl.trimEnd('/')}/$repoPath"
             "smb" -> "smb:${backendUrl.trimEnd('/')}/$repoPath"
             else -> repoPath
         }
-    }
 }

app/src/main/java/com/example/androidbackupgui/backup/ResticMaintenance.kt

@@ -1,21 +1,18 @@
 package com.example.androidbackupgui.backup
 
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.withContext
 import com.example.androidbackupgui.backup.AppError
 import com.example.androidbackupgui.backup.AppResult
 import com.example.androidbackupgui.backup.err
-import java.io.File
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 
 /**
- * Repository maintenance operations: prune, check, stats.
+ * Repository maintenance operations: prune, unlock, check, stats.
  *
  * [prune] requires both download and upload (it removes pack files from the remote).
  * [check] and [stats] are download-only read operations.
  *
- * For remote backends, uses [RestBridgeRunner] to serve the backend via REST,
- * so restic always sees a local rest-server repository. For local backends,
- * operates directly on the repo path.
+ * 使用 [BackendExecutor] 统一处理 local/remote 后端。
  *
  * Delegates execution to [ResticCommandRunner], [ResticEnvResolver], and
  * [RestBridgeRunner] which are shared across sub-modules.
@@ -23,7 +20,8 @@ import java.io.File
 class ResticMaintenance(
     private val runner: ResticCommandRunner,
     private val envResolver: ResticEnvResolver,
-    private val bridgeRunner: RestBridgeRunner
+    private val bridgeRunner: RestBridgeRunner,
+    private val executor: BackendExecutor = BackendExecutor(),
 ) {
     /** Cache directory for restic env and bridge temp files. Set by [ResticWrapper]. */
     var cacheDir: String = ""
@@ -31,7 +29,41 @@ class ResticMaintenance(
     /** SMB NTLM domain for remote backend. Set by [ResticWrapper]. */
     var backendDomain: String = ""
 
-    // ── Prune ──────────────────────────────────────────
+    /** Run a one-shot restic command and map the result. */
+    private suspend fun runCommand(
+        command: String,
+        failMessage: String,
+        repoPath: String,
+        password: String,
+        backend: String,
+        backendUrl: String,
+        backendUser: String,
+        backendPass: String,
+        backendShare: String,
+    ): AppResult<String> =
+        withContext(Dispatchers.IO) {
+            val result =
+                executor.runResticWithBackend(
+                    args = listOf(command),
+                    repoPath = repoPath,
+                    password = password,
+                    cacheDir = cacheDir,
+                    backend = backend,
+                    backendUrl = backendUrl,
+                    backendUser = backendUser,
+                    backendPass = backendPass,
+                    backendShare = backendShare,
+                    backendDomain = backendDomain,
+                    runner = runner,
+                    envResolver = envResolver,
+                    bridgeRunner = bridgeRunner,
+                )
+            if (result.exitCode == 0) {
+                AppResult.Success(result.stdout)
+            } else {
+                err(AppError.Restic(failMessage, result.exitCode, result.stderr))
+            }
+        }
 
     suspend fun prune(
         repoPath: String,
@@ -42,26 +74,17 @@ class ResticMaintenance(
         backendPass: String = "",
         backendShare: String = "",
     ): AppResult<String> =
-        withContext(Dispatchers.IO) {
-            if (backend == "local") {
-                val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-                val result = runner.runRestic(env, "prune")
-                if (result.exitCode == 0) AppResult.Success(result.stdout)
-                else err(AppError.Restic("restic prune 失败", result.exitCode, result.stderr))
-            } else {
-                bridgeRunner.withBridge(
-                    backend, backendUrl, backendUser, backendPass, backendShare,
-                    backendDomain, repoPath, File(cacheDir)
-                ) { bridgeUrl, authToken ->
-                    val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                    val result = runner.runRestic(env, "prune")
-                    if (result.exitCode == 0) AppResult.Success(result.stdout)
-                    else err(AppError.Restic("restic prune 失败", result.exitCode, result.stderr))
-                }
-            }
-        }
-
-    // ── Unlock ──────────────────────────────────────────
+        runCommand(
+            "prune",
+            "restic prune 失败",
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     suspend fun unlock(
         repoPath: String,
@@ -72,26 +95,17 @@ class ResticMaintenance(
         backendPass: String = "",
         backendShare: String = "",
     ): AppResult<String> =
-        withContext(Dispatchers.IO) {
-            if (backend == "local") {
-                val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-                val result = runner.runRestic(env, "unlock")
-                if (result.exitCode == 0) AppResult.Success(result.stdout)
-                else err(AppError.Restic("restic unlock 失败", result.exitCode, result.stderr))
-            } else {
-                bridgeRunner.withBridge(
-                    backend, backendUrl, backendUser, backendPass, backendShare,
-                    backendDomain, repoPath, File(cacheDir)
-                ) { bridgeUrl, authToken ->
-                    val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                    val result = runner.runRestic(env, "unlock")
-                    if (result.exitCode == 0) AppResult.Success(result.stdout)
-                    else err(AppError.Restic("restic unlock 失败", result.exitCode, result.stderr))
-                }
-            }
-        }
-
-    // ── Check ──────────────────────────────────────────
+        runCommand(
+            "unlock",
+            "restic unlock 失败",
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     suspend fun check(
         repoPath: String,
@@ -102,26 +116,17 @@ class ResticMaintenance(
         backendPass: String = "",
         backendShare: String = "",
     ): AppResult<String> =
-        withContext(Dispatchers.IO) {
-            if (backend == "local") {
-                val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-                val result = runner.runRestic(env, "check")
-                if (result.exitCode == 0) AppResult.Success(result.stdout)
-                else err(AppError.Restic("restic check 失败", result.exitCode, result.stderr))
-            } else {
-                bridgeRunner.withBridge(
-                    backend, backendUrl, backendUser, backendPass, backendShare,
-                    backendDomain, repoPath, File(cacheDir)
-                ) { bridgeUrl, authToken ->
-                    val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                    val result = runner.runRestic(env, "check")
-                    if (result.exitCode == 0) AppResult.Success(result.stdout)
-                    else err(AppError.Restic("restic check 失败", result.exitCode, result.stderr))
-                }
-            }
-        }
-
-    // ── Stats ──────────────────────────────────────────
+        runCommand(
+            "check",
+            "restic check 失败",
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     suspend fun stats(
         repoPath: String,
@@ -132,22 +137,15 @@ class ResticMaintenance(
         backendPass: String = "",
         backendShare: String = "",
     ): AppResult<String> =
-        withContext(Dispatchers.IO) {
-            if (backend == "local") {
-                val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-                val result = runner.runRestic(env, "stats")
-                if (result.exitCode == 0) AppResult.Success(result.stdout)
-                else err(AppError.Restic("restic stats 失败", result.exitCode, result.stderr))
-            } else {
-                bridgeRunner.withBridge(
-                    backend, backendUrl, backendUser, backendPass, backendShare,
-                    backendDomain, repoPath, File(cacheDir)
-                ) { bridgeUrl, authToken ->
-                    val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                    val result = runner.runRestic(env, "stats")
-                    if (result.exitCode == 0) AppResult.Success(result.stdout)
-                    else err(AppError.Restic("restic stats 失败", result.exitCode, result.stderr))
-                }
-            }
-        }
+        runCommand(
+            "stats",
+            "restic stats 失败",
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 }

app/src/main/java/com/example/androidbackupgui/backup/ResticRepoInit.kt

@@ -1,11 +1,11 @@
 package com.example.androidbackupgui.backup
 
 import android.util.Log
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.withContext
 import com.example.androidbackupgui.backup.AppError
 import com.example.androidbackupgui.backup.AppResult
 import com.example.androidbackupgui.backup.err
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 import java.io.File
 
 /**
@@ -21,12 +21,14 @@ import java.io.File
 class ResticRepoInit(
     private val runner: ResticCommandRunner,
     private val envResolver: ResticEnvResolver,
-    private val bridgeRunner: RestBridgeRunner
+    private val bridgeRunner: RestBridgeRunner,
+    private val executor: BackendExecutor = BackendExecutor(),
 ) {
     private val TAG = "ResticWrapper"
 
     /** Cache directory for restic env and bridge temp files. Set by ResticWrapper. */
     var cacheDir: String = ""
+
     /** NTLM domain for SMB authentication. Set by ResticWrapper. */
     var backendDomain: String = ""
 
@@ -42,18 +44,20 @@ class ResticRepoInit(
         backendShare: String = "",
     ): AppResult<Unit> =
         withContext(Dispatchers.IO) {
-            if (backend == "local") {
-                val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-                runInit(env)
-            } else {
-                bridgeRunner.withBridge(
-                    backend, backendUrl, backendUser, backendPass, backendShare,
-                    backendDomain, repoPath, File(cacheDir)
-                ) { bridgeUrl, authToken ->
-                    val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                    runInit(env)
-                }
-            }
+            executor.withBackend(
+                repoPath = repoPath,
+                password = password,
+                cacheDir = cacheDir,
+                backend = backend,
+                backendUrl = backendUrl,
+                backendUser = backendUser,
+                backendPass = backendPass,
+                backendShare = backendShare,
+                backendDomain = backendDomain,
+                runner = runner,
+                envResolver = envResolver,
+                bridgeRunner = bridgeRunner,
+            ) { env -> runInit(env) }
         }
 
     /** Shared init logic: run restic init, verify on exitCode 1. */
@@ -88,7 +92,7 @@ class ResticRepoInit(
             // Config exists but verification failed — diagnose the cause
             val detail = diagnoseInitFailure(verify.stderr)
             return err(
-                AppError.Restic("仓库已存在但无法验证: $detail", verify.exitCode, verify.stderr)
+                AppError.Restic("仓库已存在但无法验证: $detail", verify.exitCode, verify.stderr),
             )
         }
         return err(AppError.Restic("restic init 失败", result.exitCode, result.stderr))
@@ -98,15 +102,15 @@ class ResticRepoInit(
     private fun isConfigExistsError(stderr: String): Boolean {
         val lower = stderr.lowercase()
         return lower.contains("already exists") ||
-               lower.contains("config file already exists")
+            lower.contains("config file already exists")
     }
 
     /** Check if stderr indicates a stale repository lock. */
     private fun isLockError(stderr: String): Boolean {
         val lower = stderr.lowercase()
         return lower.contains("lock") ||
-               lower.contains("unable to create") ||
-               lower.contains("already locked")
+            lower.contains("unable to create") ||
+            lower.contains("already locked")
     }
 
     /** Parse restic stderr to produce a user-facing diagnosis string. */
@@ -114,25 +118,38 @@ class ResticRepoInit(
         val lower = stderr.lowercase()
         return when {
             lower.contains("wrong password") ||
-            lower.contains("password is incorrect") ||
-            lower.contains("unable to decrypt") ||
-            lower.contains("wrong key") ||
-            lower.contains("invalid password") ||
-            lower.contains("decryption") -> "密码不正确，请确认仓库密码"
-            lower.contains("key") && (lower.contains("not found") || lower.contains("missing")) ->
+                lower.contains("password is incorrect") ||
+                lower.contains("unable to decrypt") ||
+                lower.contains("wrong key") ||
+                lower.contains("invalid password") ||
+                lower.contains("decryption") -> {
+                "密码不正确，请确认仓库密码"
+            }
+
+            lower.contains("key") && (lower.contains("not found") || lower.contains("missing")) -> {
                 "密钥文件缺失，仓库可能已损坏"
-            lower.contains("permission") || lower.contains("access denied") ->
+            }
+
+            lower.contains("permission") || lower.contains("access denied") -> {
                 "权限不足，请检查目录权限"
-            lower.contains("not a directory") || lower.contains("no such file") ->
+            }
+
+            lower.contains("not a directory") || lower.contains("no such file") -> {
                 "仓库路径无效或不可访问"
-            else -> "仓库可能已损坏或密码不正确（${stderr.take(200).trim()}）"
+            }
+
+            else -> {
+                "仓库可能已损坏或密码不正确（${stderr.take(200).trim()}）"
+            }
         }
     }
 
     // ── Public URL helper ──────────────────────────────
 
     /** Build a display-friendly repository URL for UI. */
-    fun buildRepoUrl(backend: String, repoPath: String, backendUrl: String): String {
-        return envResolver.buildRepoUrl(backend, repoPath, backendUrl)
-    }
+    fun buildRepoUrl(
+        backend: String,
+        repoPath: String,
+        backendUrl: String,
+    ): String = envResolver.buildRepoUrl(backend, repoPath, backendUrl)
 }

app/src/main/java/com/example/androidbackupgui/backup/ResticRestBridge.kt

@@ -11,6 +11,7 @@ import kotlinx.serialization.json.Json
 import java.io.ByteArrayInputStream
 import java.io.File
 import java.util.UUID
+
 /**
  * NanoHTTPD-based REST bridge implementing the restic REST backend API.
  *
@@ -28,9 +29,8 @@ class ResticRestBridge(
     private val remoteBase: String,
     private val repoPath: String,
     private val cacheDir: File,
-    private val authToken: String = ""
+    private val authToken: String = "",
 ) : NanoHTTPD("127.0.0.1", 0) {
-
     private val TAG = "ResticRestBridge"
 
     init {
@@ -46,15 +46,19 @@ class ResticRestBridge(
 
         // Auth check (defense-in-depth — bridge is already bound to 127.0.0.1)
         if (authToken.isNotEmpty()) {
-            val expected = "Basic " + Base64.encodeToString(
-                "$authToken:$authToken".toByteArray(Charsets.UTF_8),
-                Base64.NO_WRAP
-            )
+            val expected =
+                "Basic " +
+                    Base64.encodeToString(
+                        "$authToken:$authToken".toByteArray(Charsets.UTF_8),
+                        Base64.NO_WRAP,
+                    )
             val auth = headers["authorization"]
             if (auth != expected) {
                 Log.w(TAG, "auth failed (got=${auth?.take(20)}..., expected=Basic $authToken)")
                 return newFixedLengthResponse(
-                    Response.Status.UNAUTHORIZED, "text/plain", "Unauthorized"
+                    Response.Status.UNAUTHORIZED,
+                    "text/plain",
+                    "Unauthorized",
                 )
             }
         }
@@ -68,7 +72,7 @@ class ResticRestBridge(
             newFixedLengthResponse(
                 Response.Status.INTERNAL_ERROR,
                 "text/plain",
-                e.message ?: "Internal error"
+                e.message ?: "Internal error",
             )
         }
     }
@@ -78,28 +82,38 @@ class ResticRestBridge(
         uri: String,
         headers: Map<String, String>,
         params: Map<String, String>,
-        session: IHTTPSession
+        session: IHTTPSession,
     ): Response {
         val path = uri.trimEnd('/')
         // Strip the repoPath prefix (/backup/...) from the URI so that type/name
         // parsing sees only the restic REST API segment.
         val stripPrefix = if (repoPath.isNotEmpty()) "/${repoPath.trim('/')}" else ""
-        val strippedPath = if (stripPrefix.isNotEmpty() && path.startsWith(stripPrefix)) {
-            path.removePrefix(stripPrefix).ifEmpty { "/" }
-        } else {
-            path
-        }
+        val strippedPath =
+            if (stripPrefix.isNotEmpty() && path.startsWith(stripPrefix)) {
+                path.removePrefix(stripPrefix).ifEmpty { "/" }
+            } else {
+                path
+            }
 
         // POST {path}?create=true -> mkdirs
         if (method == NanoHTTPD.Method.POST && params["create"] == "true") {
             return runBlocking {
                 when (transport.mkdirs(remoteBase)) {
-                    is AppResult.Success -> newFixedLengthResponse(
-                        Response.Status.OK, "text/plain", ""
-                    )
-                    is AppResult.Failure -> newFixedLengthResponse(
-                        Response.Status.INTERNAL_ERROR, "text/plain", "mkdirs failed"
-                    )
+                    is AppResult.Success -> {
+                        newFixedLengthResponse(
+                            Response.Status.OK,
+                            "text/plain",
+                            "",
+                        )
+                    }
+
+                    is AppResult.Failure -> {
+                        newFixedLengthResponse(
+                            Response.Status.INTERNAL_ERROR,
+                            "text/plain",
+                            "mkdirs failed",
+                        )
+                    }
                 }
             }
         }
@@ -138,11 +152,15 @@ class ResticRestBridge(
     }
 
     // -- Config endpoints -------------------------------------------
+
     /**
      * Stream body from session input to a temp file to avoid OOM on large blobs.
      * Returns the temp file (caller must delete).
      */
-    private fun streamBodyToFile(session: IHTTPSession, tmpDir: File): Result<File> {
+    private fun streamBodyToFile(
+        session: IHTTPSession,
+        tmpDir: File,
+    ): Result<File> {
         val started = System.currentTimeMillis()
         return try {
             val tmpFile = File(tmpDir, "restic_blob_${UUID.randomUUID()}")
@@ -162,7 +180,10 @@ class ResticRestBridge(
                         remaining -= n
                     }
                     if (remaining > 0) {
-                        Log.w(TAG, "streamBodyToFile: body truncated, expected $contentLength bytes but got EOF after ${contentLength - remaining}")
+                        Log.w(
+                            TAG,
+                            "streamBodyToFile: body truncated, expected $contentLength bytes but got EOF after ${contentLength - remaining}",
+                        )
                     }
                     Unit
                 } else {
@@ -184,87 +205,147 @@ class ResticRestBridge(
     private fun handleConfig(
         method: NanoHTTPD.Method,
         headers: Map<String, String>,
-        session: IHTTPSession
-    ): Response = runBlocking {
-        val remotePath = "$remoteBase/config"
-        when (method) {
-            NanoHTTPD.Method.HEAD -> {
-                when (val exists = transport.exists(remotePath)) {
-                    is AppResult.Success -> {
-                        if (exists.data) {
-                            val sizeResult = transport.fileSize(remotePath)
-                            val fileSize = if (sizeResult is AppResult.Success) sizeResult.data else 0L
-                            newFixedLengthResponse(
-                                Response.Status.OK, "application/octet-stream",
-                                ByteArrayInputStream(ByteArray(0)), fileSize
-                            )
-                        } else {
-                            newFixedLengthResponse(Response.Status.NOT_FOUND, "text/plain", "")
-                        }
-                    }
-                    is AppResult.Failure -> newFixedLengthResponse(
-                        Response.Status.NOT_FOUND, "text/plain", ""
-                    )
-                }
-            }
-            NanoHTTPD.Method.GET -> {
-                val tempFile = File(cacheDir, "restic_blob_${UUID.randomUUID()}")
-                try {
-                    when (transport.download(remotePath, tempFile.absolutePath)) {
+        session: IHTTPSession,
+    ): Response =
+        runBlocking {
+            val remotePath = "$remoteBase/config"
+            when (method) {
+                NanoHTTPD.Method.HEAD -> {
+                    var configExists = false
+                    var configSize = 0L
+                    // 先试 exists，失败时回退到 download 确认（某些 SMB 实现 exists 可能假阴性）
+                    when (val exists = transport.exists(remotePath)) {
                         is AppResult.Success -> {
-                            val data = tempFile.readBytes()
-                            newFixedLengthResponse(Response.Status.OK, "application/octet-stream", data.inputStream(), data.size.toLong())
+                            if (exists.data) {
+                                configExists = true
+                                val sizeResult = transport.fileSize(remotePath)
+                                if (sizeResult is AppResult.Success) configSize = sizeResult.data
+                            }
                         }
-                        is AppResult.Failure -> newFixedLengthResponse(
-                            Response.Status.NOT_FOUND, "text/plain", ""
+
+                        is AppResult.Failure -> { /* fall through to download check */ }
+                    }
+                    if (!configExists) {
+                        // Fallback: try downloading the config file to confirm existence
+                        val tmp = File(cacheDir, "restic_blob_${UUID.randomUUID()}")
+                        try {
+                            when (transport.download(remotePath, tmp.absolutePath)) {
+                                is AppResult.Success -> {
+                                    configExists = true
+                                    configSize = tmp.length()
+                                }
+
+                                is AppResult.Failure -> { /* truly not found */ }
+                            }
+                        } finally {
+                            tmp.delete()
+                        }
+                    }
+                    if (configExists) {
+                        newFixedLengthResponse(
+                            Response.Status.OK,
+                            "application/octet-stream",
+                            ByteArrayInputStream(ByteArray(0)),
+                            configSize,
+                        )
+                    } else {
+                        newFixedLengthResponse(Response.Status.NOT_FOUND, "text/plain", "")
+                    }
+                }
+
+                NanoHTTPD.Method.GET -> {
+                    val tempFile = File(cacheDir, "restic_blob_${UUID.randomUUID()}")
+                    try {
+                        when (transport.download(remotePath, tempFile.absolutePath)) {
+                            is AppResult.Success -> {
+                                val data = tempFile.readBytes()
+                                newFixedLengthResponse(
+                                    Response.Status.OK,
+                                    "application/octet-stream",
+                                    data.inputStream(),
+                                    data.size.toLong(),
+                                )
+                            }
+
+                            is AppResult.Failure -> {
+                                newFixedLengthResponse(
+                                    Response.Status.NOT_FOUND,
+                                    "text/plain",
+                                    "",
+                                )
+                            }
+                        }
+                    } finally {
+                        tempFile.delete()
+                    }
+                }
+
+                NanoHTTPD.Method.POST -> {
+                    val tmpResult = streamBodyToFile(session, cacheDir)
+                    if (tmpResult.isFailure) {
+                        return@runBlocking newFixedLengthResponse(
+                            Response.Status.INTERNAL_ERROR,
+                            "text/plain",
+                            "body read failed: ${tmpResult.exceptionOrNull()?.message ?: "unknown"}",
                         )
                     }
-                } finally {
-                    tempFile.delete()
-                }
-            }
-            NanoHTTPD.Method.POST -> {
-                val tmpResult = streamBodyToFile(session, cacheDir)
-                if (tmpResult.isFailure) return@runBlocking newFixedLengthResponse(
-                    Response.Status.INTERNAL_ERROR, "text/plain",
-                    "body read failed: ${tmpResult.exceptionOrNull()?.message ?: "unknown"}"
-                )
-                val tmpFile = tmpResult.getOrThrow()
-                try {
-                    when (transport.upload(tmpFile.absolutePath, remotePath)) {
-                        is AppResult.Success -> newFixedLengthResponse(
-                            Response.Status.OK, "text/plain", ""
-                        )
-                        is AppResult.Failure -> newFixedLengthResponse(
-                            Response.Status.INTERNAL_ERROR, "text/plain", "upload failed"
-                        )
+                    val tmpFile = tmpResult.getOrThrow()
+                    try {
+                        when (transport.upload(tmpFile.absolutePath, remotePath)) {
+                            is AppResult.Success -> {
+                                newFixedLengthResponse(
+                                    Response.Status.OK,
+                                    "text/plain",
+                                    "",
+                                )
+                            }
+
+                            is AppResult.Failure -> {
+                                newFixedLengthResponse(
+                                    Response.Status.INTERNAL_ERROR,
+                                    "text/plain",
+                                    "upload failed",
+                                )
+                            }
+                        }
+                    } finally {
+                        tmpFile.delete()
                     }
-                } finally {
-                    tmpFile.delete()
+                }
+
+                else -> {
+                    newFixedLengthResponse(Response.Status.METHOD_NOT_ALLOWED, "text/plain", "")
                 }
             }
-            else -> newFixedLengthResponse(Response.Status.METHOD_NOT_ALLOWED, "text/plain", "")
         }
-    }
 
     // -- Blob listing -----------------------------------------------
 
-    private fun handleListBlobs(type: String): Response = runBlocking {
-        val remoteDir = "$remoteBase/$type"
-        when (val result = transport.listFiles(remoteDir)) {
-            is AppResult.Success -> {
-                val items = result.data
-                val json = buildV2Json(items)
-                newFixedLengthResponse(Response.Status.OK, "application/vnd.x.restic.rest.v2", json)
+    private fun handleListBlobs(type: String): Response =
+        runBlocking {
+            val remoteDir = "$remoteBase/$type"
+            when (val result = transport.listFiles(remoteDir)) {
+                is AppResult.Success -> {
+                    val items = result.data
+                    val json = buildV2Json(items)
+                    newFixedLengthResponse(Response.Status.OK, "application/vnd.x.restic.rest.v2", json)
+                }
+
+                is AppResult.Failure -> {
+                    newFixedLengthResponse(
+                        Response.Status.NOT_FOUND,
+                        "text/plain",
+                        "",
+                    )
+                }
             }
-            is AppResult.Failure -> newFixedLengthResponse(
-                Response.Status.NOT_FOUND, "text/plain", ""
-            )
         }
-    }
 
     @Serializable
-    data class BlobEntry(val name: String, val size: Long)
+    data class BlobEntry(
+        val name: String,
+        val size: Long,
+    )
 
     private fun buildV2Json(items: List<RemoteTransport.RemoteFileInfo>): String {
         val blobs = items.filter { !it.isDirectory }.map { BlobEntry(it.name, it.size) }
@@ -273,130 +354,181 @@ class ResticRestBridge(
 
     // -- Blob HEAD (exists + size) ----------------------------------
 
-    private fun handleHeadBlob(type: String, name: String): Response = runBlocking {
-        val remotePath = "$remoteBase/$type/$name"
-        when (val result = transport.exists(remotePath)) {
-            is AppResult.Success -> {
-                if (result.data) {
-                    newFixedLengthResponse(Response.Status.OK, "application/octet-stream", "")
-                } else {
-                    newFixedLengthResponse(Response.Status.NOT_FOUND, "text/plain", "")
+    private fun handleHeadBlob(
+        type: String,
+        name: String,
+    ): Response =
+        runBlocking {
+            val remotePath = "$remoteBase/$type/$name"
+            when (val result = transport.exists(remotePath)) {
+                is AppResult.Success -> {
+                    if (result.data) {
+                        newFixedLengthResponse(Response.Status.OK, "application/octet-stream", "")
+                    } else {
+                        newFixedLengthResponse(Response.Status.NOT_FOUND, "text/plain", "")
+                    }
+                }
+
+                is AppResult.Failure -> {
+                    newFixedLengthResponse(
+                        Response.Status.NOT_FOUND,
+                        "text/plain",
+                        "",
+                    )
                 }
             }
-            is AppResult.Failure -> newFixedLengthResponse(
-                Response.Status.NOT_FOUND, "text/plain", ""
-            )
         }
-    }
 
     // -- Blob GET (download with optional Range) --------------------
 
     private fun handleGetBlob(
         type: String,
         name: String,
-        headers: Map<String, String>
-    ): Response = runBlocking {
-        val remotePath = "$remoteBase/$type/$name"
-        // Use RandomAccessFile to avoid loading entire blob into memory
-        val tempFile = File(cacheDir, "restic_blob_${UUID.randomUUID()}")
-        try {
-            when (transport.download(remotePath, tempFile.absolutePath)) {
-                is AppResult.Success -> {
-                    val rangeHeader = headers["range"]?.lowercase()
+        headers: Map<String, String>,
+    ): Response =
+        runBlocking {
+            val remotePath = "$remoteBase/$type/$name"
+            // Use RandomAccessFile to avoid loading entire blob into memory
+            val tempFile = File(cacheDir, "restic_blob_${UUID.randomUUID()}")
+            try {
+                when (transport.download(remotePath, tempFile.absolutePath)) {
+                    is AppResult.Success -> {
+                        val rangeHeader = headers["range"]?.lowercase()
 
-                    if (rangeHeader != null && rangeHeader.startsWith("bytes=")) {
-                        // Range request — only works with known file size
-                        val fileLen = tempFile.length()
-                        val range = rangeHeader.removePrefix("bytes=").trim()
-                        val dashIdx = range.indexOf('-')
-                        val start = range.substring(0, if (dashIdx >= 0) dashIdx else range.length)
-                            .toLongOrNull() ?: 0L
-                        val end = if (dashIdx >= 0 && dashIdx + 1 < range.length) {
-                            range.substring(dashIdx + 1).toLongOrNull() ?: (fileLen - 1)
-                        } else {
-                            fileLen - 1
+                        if (rangeHeader != null && rangeHeader.startsWith("bytes=")) {
+                            // Range request — only works with known file size
+                            val fileLen = tempFile.length()
+                            val range = rangeHeader.removePrefix("bytes=").trim()
+                            val dashIdx = range.indexOf('-')
+                            val start =
+                                range
+                                    .substring(0, if (dashIdx >= 0) dashIdx else range.length)
+                                    .toLongOrNull() ?: 0L
+                            val end =
+                                if (dashIdx >= 0 && dashIdx + 1 < range.length) {
+                                    range.substring(dashIdx + 1).toLongOrNull() ?: (fileLen - 1)
+                                } else {
+                                    fileLen - 1
+                                }
+
+                            val actualEnd = minOf(end, fileLen - 1).coerceAtLeast(0)
+                            val actualStart = minOf(start, actualEnd).coerceAtLeast(0)
+                            val chunkSize = (actualEnd - actualStart + 1).toInt()
+                            val chunk = ByteArray(chunkSize)
+                            try {
+                                val raf = java.io.RandomAccessFile(tempFile, "r")
+                                raf.use {
+                                    it.seek(actualStart)
+                                    it.readFully(chunk)
+                                }
+                            } catch (_: Exception) {
+                                return@runBlocking newFixedLengthResponse(
+                                    Response.Status.INTERNAL_ERROR,
+                                    "text/plain",
+                                    "range read failed",
+                                )
+                            }
+
+                            val response =
+                                newChunkedResponse(
+                                    Response.Status.PARTIAL_CONTENT,
+                                    "application/octet-stream",
+                                    chunk.inputStream(),
+                                )
+                            response.addHeader("Content-Range", "bytes $actualStart-$actualEnd/$fileLen")
+                            response.addHeader("Content-Length", chunkSize.toString())
+                            return@runBlocking response
                         }
-
-                        val actualEnd = minOf(end, fileLen - 1).coerceAtLeast(0)
-                        val actualStart = minOf(start, actualEnd).coerceAtLeast(0)
-                        val chunkSize = (actualEnd - actualStart + 1).toInt()
-                        val chunk = ByteArray(chunkSize)
-                        try {
-                            val raf = java.io.RandomAccessFile(tempFile, "r")
-                            raf.use { it.seek(actualStart); it.readFully(chunk) }
-                        } catch (_: Exception) {
-                            return@runBlocking newFixedLengthResponse(
-                                Response.Status.INTERNAL_ERROR, "text/plain", "range read failed"
+                        // Full file — read into memory (blobs are typically small)
+                        val data = tempFile.readBytes()
+                        val response =
+                            newChunkedResponse(
+                                Response.Status.OK,
+                                "application/octet-stream",
+                                data.inputStream(),
                             )
-                        }
-
-                        val response = newChunkedResponse(
-                            Response.Status.PARTIAL_CONTENT,
-                            "application/octet-stream",
-                            chunk.inputStream()
-                        )
-                        response.addHeader("Content-Range", "bytes $actualStart-$actualEnd/$fileLen")
-                        response.addHeader("Content-Length", chunkSize.toString())
-                        return@runBlocking response
+                        response.addHeader("Content-Length", data.size.toString())
+                        response
+                    }
+
+                    is AppResult.Failure -> {
+                        newFixedLengthResponse(
+                            Response.Status.NOT_FOUND,
+                            "text/plain",
+                            "",
+                        )
                     }
-                    // Full file — read into memory (blobs are typically small)
-                    val data = tempFile.readBytes()
-                    val response = newChunkedResponse(
-                        Response.Status.OK,
-                        "application/octet-stream",
-                        data.inputStream()
-                    )
-                    response.addHeader("Content-Length", data.size.toString())
-                    response
                 }
-                is AppResult.Failure -> newFixedLengthResponse(
-                    Response.Status.NOT_FOUND, "text/plain", ""
-                )
+            } finally {
+                tempFile.delete()
             }
-        } finally {
-            tempFile.delete()
         }
-    }
 
     // -- Blob POST (upload) -----------------------------------------
 
     private fun handlePostBlob(
         type: String,
         name: String,
-        session: IHTTPSession
-    ): Response = runBlocking {
-        val remotePath = "$remoteBase/$type/$name"
-        val tmpResult = streamBodyToFile(session, cacheDir)
-        if (tmpResult.isFailure) return@runBlocking newFixedLengthResponse(
-            Response.Status.INTERNAL_ERROR, "text/plain",
-            "body read failed: ${tmpResult.exceptionOrNull()?.message ?: "unknown"}"
-        )
-        val tmpFile = tmpResult.getOrThrow()
-        try {
-            when (transport.upload(tmpFile.absolutePath, remotePath)) {
-                is AppResult.Success -> newFixedLengthResponse(
-                    Response.Status.OK, "text/plain", ""
-                )
-                is AppResult.Failure -> newFixedLengthResponse(
-                    Response.Status.INTERNAL_ERROR, "text/plain", "upload failed"
+        session: IHTTPSession,
+    ): Response =
+        runBlocking {
+            val remotePath = "$remoteBase/$type/$name"
+            val tmpResult = streamBodyToFile(session, cacheDir)
+            if (tmpResult.isFailure) {
+                return@runBlocking newFixedLengthResponse(
+                    Response.Status.INTERNAL_ERROR,
+                    "text/plain",
+                    "body read failed: ${tmpResult.exceptionOrNull()?.message ?: "unknown"}",
                 )
             }
-        } finally {
-            tmpFile.delete()
+            val tmpFile = tmpResult.getOrThrow()
+            try {
+                when (transport.upload(tmpFile.absolutePath, remotePath)) {
+                    is AppResult.Success -> {
+                        newFixedLengthResponse(
+                            Response.Status.OK,
+                            "text/plain",
+                            "",
+                        )
+                    }
+
+                    is AppResult.Failure -> {
+                        newFixedLengthResponse(
+                            Response.Status.INTERNAL_ERROR,
+                            "text/plain",
+                            "upload failed",
+                        )
+                    }
+                }
+            } finally {
+                tmpFile.delete()
+            }
         }
-    }
 
     // -- Blob DELETE ------------------------------------------------
 
-    private fun handleDeleteBlob(type: String, name: String): Response = runBlocking {
-        val remotePath = "$remoteBase/$type/$name"
-        when (transport.delete(remotePath)) {
-            is AppResult.Success -> newFixedLengthResponse(
-                Response.Status.OK, "text/plain", ""
-            )
-            is AppResult.Failure -> newFixedLengthResponse(
-                Response.Status.INTERNAL_ERROR, "text/plain", "delete failed"
-            )
+    private fun handleDeleteBlob(
+        type: String,
+        name: String,
+    ): Response =
+        runBlocking {
+            val remotePath = "$remoteBase/$type/$name"
+            when (transport.delete(remotePath)) {
+                is AppResult.Success -> {
+                    newFixedLengthResponse(
+                        Response.Status.OK,
+                        "text/plain",
+                        "",
+                    )
+                }
+
+                is AppResult.Failure -> {
+                    newFixedLengthResponse(
+                        Response.Status.INTERNAL_ERROR,
+                        "text/plain",
+                        "delete failed",
+                    )
+                }
+            }
         }
-    }
 }

app/src/main/java/com/example/androidbackupgui/backup/ResticRestore.kt

@@ -1,46 +1,31 @@
 package com.example.androidbackupgui.backup
 
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.isActive
-import kotlinx.coroutines.withContext
-import kotlinx.coroutines.CancellationException
-import java.io.File
-import kotlin.coroutines.coroutineContext
 import com.example.androidbackupgui.backup.AppError
 import com.example.androidbackupgui.backup.AppResult
 import com.example.androidbackupgui.backup.err
-
+import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.withContext
+import java.io.File
+import kotlin.coroutines.coroutineContext
 
 /**
  * Restore operations: full directory restore and single-file dump.
  *
- * Both are download-only operations (no upload to remote needed).
- * Delegates execution to [ResticCommandRunner], [ResticEnvResolver], and
- * [RestBridgeRunner] which are shared across sub-modules.
- *
- * @property cacheDir Cache directory for restic env and bridge temp files; set by [ResticWrapper].
- * @property backendDomain Domain for SMB NTLM authentication; set by [ResticWrapper].
+ * 使用 [BackendExecutor] 统一处理 local/remote 后端。
  */
 class ResticRestore(
     private val runner: ResticCommandRunner,
     private val envResolver: ResticEnvResolver,
-    private val bridgeRunner: RestBridgeRunner
+    private val bridgeRunner: RestBridgeRunner,
+    private val executor: BackendExecutor = BackendExecutor(),
 ) {
-    /** Cache directory for restic env and bridge temp files. Set by [ResticWrapper]. */
     var cacheDir: String = ""
-
-    /** Domain for SMB NTLM authentication. Set by [ResticWrapper]. */
     var backendDomain: String = ""
 
     // ── Restore ────────────────────────────────────────
 
-    /**
-     * Restore a snapshot to [targetPath], optionally filtered by [include] pattern.
-     *
-     * For local backends, builds env via [ResticEnvResolver.buildLocalEnv] and runs
-     * restic restore directly. For remote backends, proxies through [RestBridgeRunner]
-     * using a local REST bridge, building env via [ResticEnvResolver.buildBridgeEnv].
-     */
     suspend fun restore(
         repoPath: String,
         password: String,
@@ -52,77 +37,63 @@ class ResticRestore(
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-        onProgress: suspend (String) -> Unit = {}
-    ): AppResult<Unit> = withContext(Dispatchers.IO) {
-        val emit: suspend (String) -> Unit = { s -> withContext(Dispatchers.Main) { onProgress(s) } }
-
-        if (backend == "local") {
+        onProgress: suspend (String) -> Unit = {},
+    ): AppResult<Unit> =
+        withContext(Dispatchers.IO) {
+            val emit: suspend (String) -> Unit = { s -> withContext(Dispatchers.Main) { onProgress(s) } }
             File(targetPath).mkdirs()
 
             val args = mutableListOf("restore", snapshotId, "--target", targetPath, "--json")
-            if (include != null) { args.add("--include"); args.add(include) }
+            if (include != null) {
+                args.add("--include")
+                args.add(include)
+            }
 
-            val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-            val result = runner.runResticStreaming(env, args) { line ->
-                if (!coroutineContext.isActive) return@runResticStreaming
-                try {
-                    val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
-                    when (progress.messageType) {
-                        "status" -> {
-                            val percent = "%.1f".format(progress.percentDone * 100)
-                            emit("恢复进度: $percent%")
-                        }
-                        "summary" -> {
-                            emit("恢复完成: ${progress.totalFiles} 个文件")
+            val result =
+                executor.withBackend(
+                    repoPath = repoPath,
+                    password = password,
+                    cacheDir = cacheDir,
+                    backend = backend,
+                    backendUrl = backendUrl,
+                    backendUser = backendUser,
+                    backendPass = backendPass,
+                    backendShare = backendShare,
+                    backendDomain = backendDomain,
+                    runner = runner,
+                    envResolver = envResolver,
+                    bridgeRunner = bridgeRunner,
+                ) { env ->
+                    runner.runResticStreaming(env, args) { line ->
+                        if (!coroutineContext.isActive) return@runResticStreaming
+                        try {
+                            val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
+                            when (progress.messageType) {
+                                "status" -> {
+                                    val percent = "%.1f".format(progress.percentDone * 100)
+                                    emit("恢复进度: $percent%")
+                                }
+
+                                "summary" -> {
+                                    emit("恢复完成: ${progress.totalFiles} 个文件")
+                                }
+                            }
+                        } catch (e: Exception) {
+                            if (e is CancellationException) throw e
+                            emit(line)
                         }
                     }
-                } catch (e: Exception) { if (e is CancellationException) throw e; emit(line) }
-            }
-
-            if (result.exitCode == 0) AppResult.Success(Unit)
-            else err(AppError.Restic("restic restore 失败", result.exitCode, result.stderr))
-        } else {
-            bridgeRunner.withBridge(
-                backend, backendUrl, backendUser, backendPass, backendShare, backendDomain,
-                repoPath, File(cacheDir)
-            ) { bridgeUrl, authToken ->
-                File(targetPath).mkdirs()
-
-                val args = mutableListOf("restore", snapshotId, "--target", targetPath, "--json")
-                if (include != null) { args.add("--include"); args.add(include) }
-
-                val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                val result = runner.runResticStreaming(env, args) { line ->
-                    if (!coroutineContext.isActive) return@runResticStreaming
-                    try {
-                        val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
-                        when (progress.messageType) {
-                            "status" -> {
-                                val percent = "%.1f".format(progress.percentDone * 100)
-                                emit("恢复进度: $percent%")
-                            }
-                            "summary" -> {
-                                emit("恢复完成: ${progress.totalFiles} 个文件")
-                            }
-                        }
-                } catch (e: Exception) { if (e is CancellationException) throw e; emit(line) }
                 }
 
-                if (result.exitCode == 0) AppResult.Success(Unit)
-                else err(AppError.Restic("restic restore 失败", result.exitCode, result.stderr))
+            if (result.exitCode == 0) {
+                AppResult.Success(Unit)
+            } else {
+                err(AppError.Restic("restic restore 失败", result.exitCode, result.stderr))
             }
         }
-    }
 
     // ── File dump ──────────────────────────────────────
 
-    /**
-     * Dump the contents of a single file from a snapshot.
-     *
-     * For local backends, builds env via [ResticEnvResolver.buildLocalEnv] and runs
-     * restic dump directly. For remote backends, proxies through [RestBridgeRunner]
-     * using a local REST bridge, building env via [ResticEnvResolver.buildBridgeEnv].
-     */
     suspend fun dump(
         repoPath: String,
         password: String,
@@ -132,23 +103,29 @@ class ResticRestore(
         backendUrl: String = "",
         backendUser: String = "",
         backendPass: String = "",
-        backendShare: String = ""
-    ): AppResult<String> = withContext(Dispatchers.IO) {
-        if (backend == "local") {
-            val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-            val result = runner.runRestic(env, "dump", snapshotId, filePath)
-            if (result.exitCode == 0) AppResult.Success(result.stdout)
-            else err(AppError.Restic(result.stderr.ifEmpty { "restic dump 失败" }, result.exitCode, result.stderr))
-        } else {
-            bridgeRunner.withBridge(
-                backend, backendUrl, backendUser, backendPass, backendShare, backendDomain,
-                repoPath, File(cacheDir)
-            ) { bridgeUrl, authToken ->
-                val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                val result = runner.runRestic(env, "dump", snapshotId, filePath)
-                if (result.exitCode == 0) AppResult.Success(result.stdout)
-                else err(AppError.Restic(result.stderr.ifEmpty { "restic dump 失败" }, result.exitCode, result.stderr))
+        backendShare: String = "",
+    ): AppResult<String> =
+        withContext(Dispatchers.IO) {
+            val result =
+                executor.withBackend(
+                    repoPath = repoPath,
+                    password = password,
+                    cacheDir = cacheDir,
+                    backend = backend,
+                    backendUrl = backendUrl,
+                    backendUser = backendUser,
+                    backendPass = backendPass,
+                    backendShare = backendShare,
+                    backendDomain = backendDomain,
+                    runner = runner,
+                    envResolver = envResolver,
+                    bridgeRunner = bridgeRunner,
+                ) { env -> runner.runRestic(env, "dump", snapshotId, filePath) }
+
+            if (result.exitCode == 0) {
+                AppResult.Success(result.stdout)
+            } else {
+                err(AppError.Restic(result.stderr.ifEmpty { "restic dump 失败" }, result.exitCode, result.stderr))
             }
         }
-    }
 }

app/src/main/java/com/example/androidbackupgui/backup/ResticSnapshotOps.kt

@@ -1,33 +1,25 @@
 package com.example.androidbackupgui.backup
 
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.withContext
 import com.example.androidbackupgui.backup.AppError
 import com.example.androidbackupgui.backup.AppResult
 import com.example.androidbackupgui.backup.err
-import java.io.File
-
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
 
 /**
  * Snapshot listing and retention policy operations.
  *
  * [listSnapshots] is download-only; [forget] removes snapshots from the remote.
  *
- * For "local" backends, invokes restic directly against [repoPath].
- * For remote backends (SMB/WebDAV/rest-server), starts a temporary REST bridge
- * via [RestBridgeRunner.withBridge] and points restic at the bridge URL.
- *
- * Delegates execution to [ResticCommandRunner], [ResticEnvResolver], and
- * [RestBridgeRunner] which are shared across sub-modules.
+ * 使用 [BackendExecutor] 统一处理 local/remote 后端。
  */
 class ResticSnapshotOps(
     private val runner: ResticCommandRunner,
     private val envResolver: ResticEnvResolver,
-    private val bridgeRunner: RestBridgeRunner
+    private val bridgeRunner: RestBridgeRunner,
+    private val executor: BackendExecutor = BackendExecutor(),
 ) {
-    /** Cache directory for restic env and bridge temp files. Set by ResticWrapper. */
     var cacheDir: String = ""
-    /** NTLM domain for SMB authentication. Set by ResticWrapper. */
     var backendDomain: String = ""
 
     // ── List snapshots ─────────────────────────────────
@@ -41,52 +33,44 @@ class ResticSnapshotOps(
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<List<ResticWrapper.ResticSnapshot>> = withContext(Dispatchers.IO) {
-        if (backend == "local") {
+    ): AppResult<List<ResticWrapper.ResticSnapshot>> =
+        withContext(Dispatchers.IO) {
             val args = mutableListOf("snapshots", "--json")
-            if (tag != null) { args.add("--tag"); args.add(tag) }
+            if (tag != null) {
+                args.add("--tag")
+                args.add(tag)
+            }
 
-            val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-            val result = runner.runRestic(env, args)
+            val result =
+                executor.withBackend(
+                    repoPath = repoPath,
+                    password = password,
+                    cacheDir = cacheDir,
+                    backend = backend,
+                    backendUrl = backendUrl,
+                    backendUser = backendUser,
+                    backendPass = backendPass,
+                    backendShare = backendShare,
+                    backendDomain = backendDomain,
+                    runner = runner,
+                    envResolver = envResolver,
+                    bridgeRunner = bridgeRunner,
+                ) { env -> runner.runRestic(env, args) }
 
             if (result.exitCode != 0) {
                 return@withContext err(AppError.Restic("restic snapshots 失败", result.exitCode, result.stderr))
             }
 
             try {
-                val snapshots = resticJson.decodeFromString<List<ResticWrapper.ResticSnapshot>>(
-                    result.stdout.ifEmpty { "[]" }
-                )
+                val snapshots =
+                    resticJson.decodeFromString<List<ResticWrapper.ResticSnapshot>>(
+                        result.stdout.ifEmpty { "[]" },
+                    )
                 AppResult.Success(snapshots.sortedByDescending { it.time })
             } catch (e: Exception) {
                 err(AppError.Parse("解析快照 JSON 失败", e.message ?: ""))
             }
-        } else {
-            bridgeRunner.withBridge(
-                backend, backendUrl, backendUser, backendPass, backendShare,
-                backendDomain, repoPath, File(cacheDir)
-            ) { bridgeUrl, authToken ->
-                val args = mutableListOf("snapshots", "--json")
-                if (tag != null) { args.add("--tag"); args.add(tag) }
-
-                val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                val result = runner.runRestic(env, args)
-
-                if (result.exitCode != 0) {
-                    return@withBridge err(AppError.Restic("restic snapshots 失败", result.exitCode, result.stderr))
-                }
-
-                try {
-                    val snapshots = resticJson.decodeFromString<List<ResticWrapper.ResticSnapshot>>(
-                        result.stdout.ifEmpty { "[]" }
-                    )
-                    AppResult.Success(snapshots.sortedByDescending { it.time })
-                } catch (e: Exception) {
-                    err(AppError.Parse("解析快照 JSON 失败", e.message ?: ""))
-                }
-            }
         }
-    }
 
     // ── Forget (retention policy) ──────────────────────
 
@@ -102,40 +86,40 @@ class ResticSnapshotOps(
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<String> = withContext(Dispatchers.IO) {
-        if (backend == "local") {
-            val args = mutableListOf(
-                "forget",
-                "--keep-daily", keepDaily.toString(),
-                "--keep-weekly", keepWeekly.toString(),
-                "--keep-monthly", keepMonthly.toString()
-            )
+    ): AppResult<String> =
+        withContext(Dispatchers.IO) {
+            val args =
+                mutableListOf(
+                    "forget",
+                    "--keep-daily",
+                    keepDaily.toString(),
+                    "--keep-weekly",
+                    keepWeekly.toString(),
+                    "--keep-monthly",
+                    keepMonthly.toString(),
+                )
             if (dryRun) args.add("--dry-run")
 
-            val env = envResolver.buildLocalEnv(repoPath, password, cacheDir)
-            val result = runner.runRestic(env, args)
+            val result =
+                executor.withBackend(
+                    repoPath = repoPath,
+                    password = password,
+                    cacheDir = cacheDir,
+                    backend = backend,
+                    backendUrl = backendUrl,
+                    backendUser = backendUser,
+                    backendPass = backendPass,
+                    backendShare = backendShare,
+                    backendDomain = backendDomain,
+                    runner = runner,
+                    envResolver = envResolver,
+                    bridgeRunner = bridgeRunner,
+                ) { env -> runner.runRestic(env, args) }
 
-            if (result.exitCode == 0) AppResult.Success(result.stdout)
-            else err(AppError.Restic("restic forget 失败", result.exitCode, result.stderr))
-        } else {
-            bridgeRunner.withBridge(
-                backend, backendUrl, backendUser, backendPass, backendShare,
-                backendDomain, repoPath, File(cacheDir)
-            ) { bridgeUrl, authToken ->
-                val args = mutableListOf(
-                    "forget",
-                    "--keep-daily", keepDaily.toString(),
-                    "--keep-weekly", keepWeekly.toString(),
-                    "--keep-monthly", keepMonthly.toString()
-                )
-                if (dryRun) args.add("--dry-run")
-
-                val env = envResolver.buildBridgeEnv(password, bridgeUrl, cacheDir, authToken)
-                val result = runner.runRestic(env, args)
-
-                if (result.exitCode == 0) AppResult.Success(result.stdout)
-                else err(AppError.Restic("restic forget 失败", result.exitCode, result.stderr))
+            if (result.exitCode == 0) {
+                AppResult.Success(result.stdout)
+            } else {
+                err(AppError.Restic("restic forget 失败", result.exitCode, result.stderr))
             }
         }
-    }
 }

app/src/main/java/com/example/androidbackupgui/backup/ResticStreamBackup.kt

@@ -0,0 +1,285 @@
+package com.example.androidbackupgui.backup
+
+import android.util.Log
+import com.example.androidbackupgui.root.RootShell
+import com.example.androidbackupgui.root.shellEscape
+import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.withContext
+import java.io.File
+import kotlin.coroutines.coroutineContext
+
+/**
+ * "流式"备份——将应用数据 tar 到临时目录，然后由 restic 统一备份。
+ *
+ * 原实现使用 FIFO + `restic backup --stdin`，但由于 RootShell 每次 exec
+ * 会独立打开/关闭 FIFO，导致 restic 在第一次写入后收到 EOF 退出。
+ *
+ * 当前实现改为：
+ * 1. 创建临时工作目录 stream_data/
+ * 2. 将元数据 + APK 文件复制到该目录
+ * 3. 对每个应用，tar 数据到该目录下的独立文件
+ * 4. 运行 restic backup 指向该目录（无 --stdin，无 FIFO）
+ * 5. 备份完成后清理临时目录
+ *
+ * 和普通备份的区别：临时目录会在备份完成后自动删除，不留本地存档。
+ * 仅当 [BackupConfig.useStreaming] 启用时使用。
+ */
+object ResticStreamBackup {
+    private const val TAG = "ResticStreamBackup"
+
+    /** 单个应用跳过备份的数据大小阈值（500MB） */
+    private const val MAX_STREAM_APP_SIZE_BYTES = 500L * 1024 * 1024
+
+    /**
+     * Run a streaming backup.
+     */
+    suspend fun backup(
+        cacheDir: File,
+        ownPackageName: String,
+        apps: List<AppInfo>,
+        noDataBackup: Set<String>,
+        legacyApps: Map<String, ResticWrapper.SnapshotAppInfo>?,
+        userId: String,
+        restic: ResticWrapper,
+        repoPath: String,
+        password: String,
+        tags: List<String>,
+        hostname: String?,
+        backend: String,
+        backendUrl: String,
+        backendUser: String,
+        backendPass: String,
+        backendShare: String,
+        onProgress: suspend (String) -> Unit = {},
+    ): AppResult<ResticWrapper.BackupSummary> =
+        withContext(Dispatchers.IO) {
+            val emit: suspend (String) -> Unit = { msg -> withContext(Dispatchers.Main) { onProgress(msg) } }
+
+            // ── 1. Create temporary work directory ──────
+            val workDir = File(cacheDir, "stream_data")
+            if (workDir.exists()) RootShell.exec("rm -rf '${workDir.absolutePath.shellEscape()}'")
+            workDir.mkdirs()
+            Log.i(TAG, "Work dir created at ${workDir.absolutePath}")
+
+            try {
+                // ── 2. Write metadata ─────────────────────
+                // 文件直接放在 workDir 根下，与普通备份结构一致
+                emit("正在准备元数据…")
+                BackupOperation.writeFileForBackup(
+                    File(workDir, "appList.txt"),
+                    apps.joinToString("\n") { it.packageName.value },
+                )
+                BackupOperation.writeFileForBackup(
+                    File(workDir, "app_details.json"),
+                    BackupOperation.buildAppDetailsJson(apps, legacyApps),
+                )
+                Log.i(TAG, "Metadata written to ${workDir.absolutePath}")
+
+                // ── 3. Backup APK files ───────────────────
+                // 统一使用 per-app 子目录结构，与普通备份和恢复代码兼容
+                emit("正在备份 APK 文件…")
+                var apkCount = 0
+                for (app in apps) {
+                    if (!coroutineContext.isActive) return@withContext err(AppError.Cancelled)
+                    val appDir = File(workDir, app.packageName.value)
+                    appDir.mkdirs()
+                    val paths = AppScanner.getApkPaths(app.packageName.value)
+                    for ((i, apkPath) in paths.withIndex()) {
+                        val destName = if (paths.size > 1) "${app.packageName.value}_split_$i.apk" else "${app.packageName.value}.apk"
+                        val cpOk =
+                            RootShell
+                                .exec(
+                                    "cp '${apkPath.shellEscape()}' '${File(appDir, destName).absolutePath.shellEscape()}' 2>/dev/null",
+                                ).isSuccess
+                        if (cpOk) apkCount++
+                    }
+                }
+                Log.i(TAG, "Backed up $apkCount APK files")
+
+                // ── 4. Backup app data ────────────────────
+                var successCount = 0
+                var failCount = 0
+
+                for ((index, app) in apps.withIndex()) {
+                    if (!coroutineContext.isActive) return@withContext err(AppError.Cancelled)
+
+                    val pkgName = app.packageName.value
+                    if (pkgName in noDataBackup) {
+                        Log.d(TAG, "backup: skipping data for $pkgName (excluded)")
+                        continue
+                    }
+
+                    emit("备份数据: $pkgName (${index + 1}/${apps.size})")
+
+                    // Force-stop app before data backup for consistency
+                    if (pkgName !in listOf("bin.mt.plus", "com.termux", "bin.mt.plus.canary", ownPackageName)) {
+                        RootShell.exec("am force-stop --user $userId '$pkgName' 2>/dev/null")
+                    }
+
+                    // Check data dirs exist
+                    val dirs = mutableListOf<String>()
+                    val dataCheck = RootShell.exec("test -d '/data/data/${pkgName.shellEscape()}' && echo 1 || echo 0")
+                    if (dataCheck.output.trim() == "1") dirs.add("/data/data/$pkgName")
+
+                    val userDeCheck =
+                        RootShell.exec(
+                            "test -d '/data/user_de/${userId.shellEscape()}/${pkgName.shellEscape()}' && echo 1 || echo 0",
+                        )
+                    if (userDeCheck.output.trim() == "1") dirs.add("/data/user_de/$userId/$pkgName")
+
+                    if (dirs.isEmpty()) {
+                        Log.d(TAG, "backup: no data dirs for $pkgName, skipping")
+                        continue
+                    }
+
+                    // Estimate size, skip oversized apps
+                    val dirArgs = dirs.joinToString(" ") { "'${it.shellEscape()}'" }
+                    val preCheck =
+                        RootShell.exec(
+                            "du -sb --exclude='cache' --exclude='code_cache' --exclude='lib' --exclude='no_backup' --exclude='.ota' $dirArgs 2>/dev/null | awk '{s+=\$1} END{print s}'",
+                        )
+                    val estimatedBytes = preCheck.output.trim().toLongOrNull() ?: 0L
+                    if (estimatedBytes > MAX_STREAM_APP_SIZE_BYTES) {
+                        emit("⚠ $pkgName 数据过大 (${estimatedBytes / 1024 / 1024}MB)，跳过")
+                        Log.w(TAG, "backup: $pkgName too large (${estimatedBytes / 1024 / 1024}MB), skipping")
+                        continue
+                    }
+
+                    // Tar app data to per-app subdirectory
+                    val appDir = File(workDir, pkgName)
+                    appDir.mkdirs()
+                    val tarFile = File(appDir, "${pkgName}_data.tar.zst")
+                    // 使用系统 tar + 捆绑的 zstd（从 cacheDir 推导 filesDir）
+                    val filesDir = File(cacheDir.parentFile, "files")
+                    val zstdBin = File(File(filesDir, "bin"), "zstd_bin")
+                    val zstdCmd = if (zstdBin.canExecute()) zstdBin.absolutePath else "zstd"
+                    val tarCmd = "set -o pipefail; tar -cf - $dirArgs --exclude='cache' --exclude='code_cache' --exclude='lib' --exclude='no_backup' --exclude='.ota' 2>/dev/null | $zstdCmd -T0 -o '${tarFile.absolutePath.shellEscape()}'"
+                    RootShell.exec("chmod +x '${zstdBin.absolutePath.shellEscape()}' 2>/dev/null")
+
+                    val result = RootShell.exec(tarCmd)
+                    if (result.isSuccess && tarFile.length() > 0) {
+                        successCount++
+                    } else {
+                        Log.w(TAG, "backup: tar failed for $pkgName exit=${result.exitCode} err='${result.error.take(200)}'")
+                        failCount++
+                    }
+                }
+
+                emit("数据备份完成 (成功 $successCount, 失败 $failCount)，正在上传至 restic…")
+
+                // ── 5. Run restic backup ──────────────────
+                val args = mutableListOf("backup", "--json")
+                args.add(workDir.absolutePath)
+                for (tag in tags) {
+                    args.add("--tag")
+                    args.add(tag)
+                }
+                if (hostname != null) {
+                    args.add("--host")
+                    args.add(hostname)
+                }
+
+                val cmdArgs = restic.runner.buildCommandArgs(args)
+                Log.i(TAG, "Running restic ${cmdArgs.joinToString(" ")}")
+
+                val result =
+                    restic.executor.runResticStreamingWithBackend(
+                        args = args,
+                        repoPath = repoPath,
+                        password = password,
+                        cacheDir = restic.cacheDir,
+                        backend = backend,
+                        backendUrl = backendUrl,
+                        backendUser = backendUser,
+                        backendPass = backendPass,
+                        backendShare = backendShare,
+                        backendDomain = restic.backendDomain,
+                        runner = restic.runner,
+                        envResolver = restic.envResolver,
+                        bridgeRunner = restic.bridgeRunner,
+                        onLine = { line ->
+                            try {
+                                val progress = resticJson.decodeFromString<ResticWrapper.ResticProgress>(line)
+                                if (progress.messageType == "status") {
+                                    val pct = "%.1f".format(progress.percentDone * 100)
+                                    emit(
+                                        "上传进度: $pct% (${progress.filesDone}/${progress.totalFiles} 文件, ${progress.bytesDone / 1024 / 1024}/${progress.totalBytes / 1024 / 1024}MB)",
+                                    )
+                                }
+                            } catch (_: Exception) {
+                                if (line.length < 200) emit(line)
+                            }
+                        },
+                    )
+
+                if (result.exitCode != 0) {
+                    Log.e(TAG, "restic backup failed: exit=${result.exitCode} stderr=${result.stderr.take(500)}")
+                    return@withContext err(AppError.Restic("restic 备份失败", result.exitCode, result.stderr))
+                }
+
+                // ── 6. Parse summary ─────────────────────
+                val summaryLine =
+                    result.stdout.lines().lastOrNull { line ->
+                        line.contains("\"message_type\"") && line.contains("\"summary\"")
+                    }
+                val summary =
+                    if (summaryLine != null) {
+                        try {
+                            resticJson.decodeFromString<ResticWrapper.BackupSummary>(summaryLine)
+                        } catch (e: Exception) {
+                            Log.w(TAG, "Failed to parse summary: ${e.message}")
+                            null
+                        }
+                    } else {
+                        null
+                    }
+
+                if (summary == null) {
+                    return@withContext err(AppError.Parse("restic 未返回摘要信息", ""))
+                }
+
+                // ── 7. Verify snapshot ───────────────────
+                val snapshotId = summary.snapshotId
+                emit("正在验证快照 ${snapshotId.take(8)}…")
+                try {
+                    restic.executor.withBackend(
+                        repoPath = repoPath,
+                        password = password,
+                        cacheDir = restic.cacheDir,
+                        backend = backend,
+                        backendUrl = backendUrl,
+                        backendUser = backendUser,
+                        backendPass = backendPass,
+                        backendShare = backendShare,
+                        backendDomain = restic.backendDomain,
+                        runner = restic.runner,
+                        envResolver = restic.envResolver,
+                        bridgeRunner = restic.bridgeRunner,
+                    ) { env ->
+                        val verifyResult = restic.runner.runRestic(env, "snapshots", "--json")
+                        if (verifyResult.exitCode == 0 && verifyResult.stdout.contains(snapshotId)) {
+                            Log.i(TAG, "backup: snapshot $snapshotId verified")
+                        } else {
+                            Log.w(TAG, "backup: snapshot $snapshotId NOT found in snapshots list!")
+                        }
+                    }
+                } catch (e: Exception) {
+                    Log.w(TAG, "backup: snapshot verification failed: ${e.message}")
+                }
+
+                AppResult.Success(summary)
+            } catch (e: CancellationException) {
+                throw e
+            } catch (e: Exception) {
+                LogUtil.e(TAG, "backup failed: ${e.message}")
+                err(AppError.Restic("流式备份异常: ${e.message}", -1, ""))
+            } finally {
+                // ── 8. Cleanup ───────────────────────────
+                emit("正在清理临时文件…")
+                RootShell.exec("rm -rf '${workDir.absolutePath.shellEscape()}'")
+                Log.i(TAG, "Work dir cleaned up")
+            }
+        }
+}

app/src/main/java/com/example/androidbackupgui/backup/ResticWrapper.kt

@@ -1,17 +1,17 @@
 package com.example.androidbackupgui.backup
 
 import android.util.Log
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.isActive
-import java.io.File
-import kotlinx.coroutines.withContext
-import org.json.JSONObject
-import kotlin.coroutines.coroutineContext
-import kotlinx.serialization.Serializable
-import kotlinx.serialization.SerialName
 import com.example.androidbackupgui.backup.AppError
 import com.example.androidbackupgui.backup.AppResult
 import com.example.androidbackupgui.backup.err
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.withContext
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+import org.json.JSONObject
+import java.io.File
+import kotlin.coroutines.coroutineContext
 
 /**
  * Wraps the restic CLI binary for backup/restore operations.
@@ -30,28 +30,42 @@ import com.example.androidbackupgui.backup.err
  * ([ResticRepoInit], [ResticBackup], [ResticRestore], [ResticSnapshotOps],
  * [ResticMaintenance]).
  */
-object ResticWrapper {
 
-    private const val TAG = "ResticWrapper"
+/**
+ * 默认 [ResticWrapper] 实例。用于不需要自定义依赖注入的场景。
+ */
+val defaultResticWrapper: ResticWrapper = ResticWrapper()
 
-    private val runner = ResticCommandRunner()
-    private val envResolver = ResticEnvResolver()
-    private val bridgeRunner = RestBridgeRunner()
+/**
+ * Wraps the restic CLI binary for backup/restore operations.
+ *
+ * 现在是一个 class 而非 object，可以通过构造函数注入依赖。
+ * 使用 [defaultResticWrapper] 获取默认单例。
+ */
+class ResticWrapper(
+    internal val runner: ResticCommandRunner = ResticCommandRunner(),
+    internal val envResolver: ResticEnvResolver = ResticEnvResolver(),
+    internal val bridgeRunner: RestBridgeRunner = RestBridgeRunner(),
+    internal val executor: BackendExecutor = BackendExecutor(),
+) {
+    private val TAG = "ResticWrapper"
 
     // ── Sub-module instances ───────────────────────────
 
-    private val repoInit = ResticRepoInit(runner, envResolver, bridgeRunner)
-    private val backupOp = ResticBackup(runner, envResolver, bridgeRunner)
-    private val restoreOp = ResticRestore(runner, envResolver, bridgeRunner)
-    private val snapshotOps = ResticSnapshotOps(runner, envResolver, bridgeRunner)
-    private val maintenance = ResticMaintenance(runner, envResolver, bridgeRunner)
+    private val repoInit = ResticRepoInit(runner, envResolver, bridgeRunner, executor)
+    private val backupOp = ResticBackup(runner, envResolver, bridgeRunner, executor)
+    private val restoreOp = ResticRestore(runner, envResolver, bridgeRunner, executor)
+    private val snapshotOps = ResticSnapshotOps(runner, envResolver, bridgeRunner, executor)
+    private val maintenance = ResticMaintenance(runner, envResolver, bridgeRunner, executor)
 
     // ── Property delegation ───────────────────────────
 
     /** Path to the restic binary. Default assumes it's on PATH (e.g. Termux). */
     var binaryPath: String
         get() = runner.binaryPath
-        set(v) { runner.binaryPath = v }
+        set(v) {
+            runner.binaryPath = v
+        }
 
     /** Cache directory for restic (XDG_CACHE_HOME) and bridge tmp blobs. */
     var cacheDir: String = ""
@@ -64,7 +78,6 @@ object ResticWrapper {
             maintenance.cacheDir = v
         }
 
-
     /** Domain for SMB NTLM authentication. Propagated to sub-modules. */
     var backendDomain: String = ""
         set(v) {
@@ -79,13 +92,13 @@ object ResticWrapper {
 
     @Serializable
     data class ResticProgress(
-        @SerialName("message_type") val messageType: String,       // "status" during backup
+        @SerialName("message_type") val messageType: String, // "status" during backup
         @SerialName("percent_done") val percentDone: Double = 0.0,
         @SerialName("total_files") val totalFiles: Int = 0,
         @SerialName("files_done") val filesDone: Int = 0,
         @SerialName("total_bytes") val totalBytes: Long = 0,
         @SerialName("bytes_done") val bytesDone: Long = 0,
-        @SerialName("current_files") val currentFiles: List<String> = emptyList()
+        @SerialName("current_files") val currentFiles: List<String> = emptyList(),
     )
 
     @Serializable
@@ -95,14 +108,14 @@ object ResticWrapper {
         val time: String,
         val paths: List<String>,
         val tags: List<String>,
-        val hostname: String = ""
+        val hostname: String = "",
     )
 
     /** App metadata read from a restic snapshot for change detection. */
     data class SnapshotAppInfo(
         val label: String,
         val isSystem: Boolean,
-        val apkSizes: List<Long> = emptyList()
+        val apkSizes: List<Long> = emptyList(),
     )
 
     // ── Repository lifecycle ─────────────────────────
@@ -115,9 +128,16 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<Unit> = repoInit.init(
-        repoPath, password, backend, backendUrl, backendUser, backendPass, backendShare
-    )
+    ): AppResult<Unit> =
+        repoInit.init(
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     // ── Backup ─────────────────────────────────────────
 
@@ -136,7 +156,7 @@ object ResticWrapper {
         @SerialName("data_added") val dataAdded: Long = 0,
         @SerialName("total_files_processed") val totalFilesProcessed: Int = 0,
         @SerialName("total_bytes_processed") val totalBytesProcessed: Long = 0,
-        @SerialName("total_duration") val totalDuration: Double = 0.0
+        @SerialName("total_duration") val totalDuration: Double = 0.0,
     )
 
     suspend fun backup(
@@ -150,33 +170,62 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-        onProgress: suspend (ResticProgress) -> Unit = {}
-    ): AppResult<BackupSummary> = backupOp.backup(
-        repoPath, password, paths, tags, hostname,
-        backend, backendUrl, backendUser, backendPass, backendShare,
-        onProgress
-    )
+        onProgress: suspend (ResticProgress) -> Unit = {},
+    ): AppResult<BackupSummary> =
+        backupOp.backup(
+            repoPath,
+            password,
+            paths,
+            tags,
+            hostname,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+            onProgress,
+        )
 
-    // ── Streaming backup (stdin) ─────────────────────
-
-    suspend fun backupStdin(
+    /**
+     * Streaming backup: pipes tar data through a FIFO directly into restic --stdin.
+     * Avoids writing a staging tarball to disk. Requires [cacheDir] to be set first.
+     */
+    suspend fun backupStreaming(
+        apps: List<AppInfo>,
+        noDataBackup: Set<String>,
+        legacyApps: Map<String, SnapshotAppInfo>?,
+        userId: String = "0",
         repoPath: String,
         password: String,
-        stdinFile: File,
-        extraPaths: List<String>,
-        tags: List<String> = emptyList(),
-        hostname: String? = null,
-        backend: String = "local",
-        backendUrl: String = "",
-        backendUser: String = "",
-        backendPass: String = "",
-        backendShare: String = "",
-        onProgress: suspend (ResticProgress) -> Unit = {}
-    ): AppResult<BackupSummary> = backupOp.backupStdin(
-        repoPath, password, stdinFile, extraPaths, tags, hostname,
-        backend, backendUrl, backendUser, backendPass, backendShare,
-        onProgress
-    )
+        tags: List<String>,
+        hostname: String?,
+        backend: String,
+        backendUrl: String,
+        backendUser: String,
+        backendPass: String,
+        backendShare: String,
+        onProgress: suspend (String) -> Unit = {},
+        ownPackageName: String = "",
+    ): AppResult<BackupSummary> =
+        ResticStreamBackup.backup(
+            cacheDir = File(cacheDir),
+            ownPackageName = ownPackageName,
+            apps = apps,
+            noDataBackup = noDataBackup,
+            legacyApps = legacyApps,
+            userId = userId,
+            restic = this,
+            repoPath = repoPath,
+            password = password,
+            tags = tags,
+            hostname = hostname,
+            backend = backend,
+            backendUrl = backendUrl,
+            backendUser = backendUser,
+            backendPass = backendPass,
+            backendShare = backendShare,
+            onProgress = onProgress,
+        )
 
     // ── Restore ────────────────────────────────────────
 
@@ -191,12 +240,21 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-        onProgress: suspend (String) -> Unit = {}
-    ): AppResult<Unit> = restoreOp.restore(
-        repoPath, password, snapshotId, targetPath, include,
-        backend, backendUrl, backendUser, backendPass, backendShare,
-        onProgress
-    )
+        onProgress: suspend (String) -> Unit = {},
+    ): AppResult<Unit> =
+        restoreOp.restore(
+            repoPath,
+            password,
+            snapshotId,
+            targetPath,
+            include,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+            onProgress,
+        )
 
     // ── File dump ──────────────────────────────────────
 
@@ -210,10 +268,18 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<String> = restoreOp.dump(
-        repoPath, password, snapshotId, filePath,
-        backend, backendUrl, backendUser, backendPass, backendShare
-    )
+    ): AppResult<String> =
+        restoreOp.dump(
+            repoPath,
+            password,
+            snapshotId,
+            filePath,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     // ── Snapshot management ────────────────────────────
 
@@ -226,10 +292,17 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<List<ResticSnapshot>> = snapshotOps.listSnapshots(
-        repoPath, password, tag,
-        backend, backendUrl, backendUser, backendPass, backendShare
-    )
+    ): AppResult<List<ResticSnapshot>> =
+        snapshotOps.listSnapshots(
+            repoPath,
+            password,
+            tag,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     suspend fun forget(
         repoPath: String,
@@ -243,10 +316,20 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<String> = snapshotOps.forget(
-        repoPath, password, keepDaily, keepWeekly, keepMonthly, dryRun,
-        backend, backendUrl, backendUser, backendPass, backendShare
-    )
+    ): AppResult<String> =
+        snapshotOps.forget(
+            repoPath,
+            password,
+            keepDaily,
+            keepWeekly,
+            keepMonthly,
+            dryRun,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     /**
      * Read [app_details.json] from the latest restic snapshot and return a map
@@ -261,37 +344,63 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): Map<String, SnapshotAppInfo>? = withContext(Dispatchers.IO) {
-        val snapsResult = snapshotOps.listSnapshots(
-            repoPath, password, tag = null,
-            backend, backendUrl, backendUser, backendPass, backendShare
-        )
-        val snaps = when (snapsResult) {
-            is AppResult.Failure -> {
-                Log.w(TAG, "getLatestSnapshotAppDetails: listSnapshots failed: ${snapsResult.error.message}")
-                null
-            }
-            is AppResult.Success -> snapsResult.data
-        } ?: return@withContext null
+    ): Map<String, SnapshotAppInfo>? =
+        withContext(Dispatchers.IO) {
+            val snapsResult =
+                snapshotOps.listSnapshots(
+                    repoPath,
+                    password,
+                    tag = null,
+                    backend,
+                    backendUrl,
+                    backendUser,
+                    backendPass,
+                    backendShare,
+                )
+            val snaps =
+                when (snapsResult) {
+                    is AppResult.Failure -> {
+                        Log.w(TAG, "getLatestSnapshotAppDetails: listSnapshots failed: ${snapsResult.error.message}")
+                        null
+                    }
 
-        if (snaps.isEmpty()) return@withContext null
+                    is AppResult.Success -> {
+                        snapsResult.data
+                    }
+                } ?: return@withContext null
 
-        val latestId = snaps.first().shortId
-        val basePath = snaps.first().paths.firstOrNull()?.trimEnd('/') ?: return@withContext null
+            if (snaps.isEmpty()) return@withContext null
 
-        val dumpResult = restoreOp.dump(
-            repoPath, password, latestId, "$basePath/app_details.json",
-            backend, backendUrl, backendUser, backendPass, backendShare
-        )
+            val latestId = snaps.first().shortId
+            val basePath =
+                snaps
+                    .first()
+                    .paths
+                    .firstOrNull()
+                    ?.trimEnd('/') ?: return@withContext null
 
-        val jsonStr = when (dumpResult) {
-            is AppResult.Failure -> return@withContext null
-            is AppResult.Success -> dumpResult.data
+            val dumpResult =
+                restoreOp.dump(
+                    repoPath,
+                    password,
+                    latestId,
+                    "$basePath/app_details.json",
+                    backend,
+                    backendUrl,
+                    backendUser,
+                    backendPass,
+                    backendShare,
+                )
+
+            val jsonStr =
+                when (dumpResult) {
+                    is AppResult.Failure -> return@withContext null
+                    is AppResult.Success -> dumpResult.data
+                }
+
+            return@withContext parseAppDetailsJson(jsonStr)
         }
 
-        return@withContext parseAppDetailsJson(jsonStr)
-    }
-
     /** Parse [app_details.json] content into a package-name → [SnapshotAppInfo] map. */
     internal fun parseAppDetailsJson(jsonStr: String): Map<String, SnapshotAppInfo> {
         val map = mutableMapOf<String, SnapshotAppInfo>()
@@ -306,11 +415,12 @@ object ResticWrapper {
                         sizes.add(sizesArr.optLong(i, 0L))
                     }
                 }
-                map[key] = SnapshotAppInfo(
-                    label = entry.optString("label", key),
-                    isSystem = entry.optBoolean("isSystem", false),
-                    apkSizes = sizes
-                )
+                map[key] =
+                    SnapshotAppInfo(
+                        label = entry.optString("label", key),
+                        isSystem = entry.optBoolean("isSystem", false),
+                        apkSizes = sizes,
+                    )
             }
         } catch (_: Exception) {
             Log.w(TAG, "parseAppDetailsJson: failed to parse JSON")
@@ -328,10 +438,16 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<String> = maintenance.prune(
-        repoPath, password,
-        backend, backendUrl, backendUser, backendPass, backendShare
-    )
+    ): AppResult<String> =
+        maintenance.prune(
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     suspend fun check(
         repoPath: String,
@@ -341,10 +457,16 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<String> = maintenance.check(
-        repoPath, password,
-        backend, backendUrl, backendUser, backendPass, backendShare
-    )
+    ): AppResult<String> =
+        maintenance.check(
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     suspend fun stats(
         repoPath: String,
@@ -354,10 +476,16 @@ object ResticWrapper {
         backendUser: String = "",
         backendPass: String = "",
         backendShare: String = "",
-    ): AppResult<String> = maintenance.stats(
-        repoPath, password,
-        backend, backendUrl, backendUser, backendPass, backendShare
-    )
+    ): AppResult<String> =
+        maintenance.stats(
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
+        )
 
     suspend fun unlock(
         repoPath: String,
@@ -369,14 +497,21 @@ object ResticWrapper {
         backendShare: String = "",
     ): AppResult<String> =
         maintenance.unlock(
-            repoPath, password,
-            backend, backendUrl, backendUser, backendPass, backendShare,
+            repoPath,
+            password,
+            backend,
+            backendUrl,
+            backendUser,
+            backendPass,
+            backendShare,
         )
 
     // ── Public URL helper ──────────────────────────────
 
     /** Build a display-friendly repository URL for UI. */
-    fun buildRepoUrl(backend: String, repoPath: String, backendUrl: String): String {
-        return repoInit.buildRepoUrl(backend, repoPath, backendUrl)
-    }
+    fun buildRepoUrl(
+        backend: String,
+        repoPath: String,
+        backendUrl: String,
+    ): String = repoInit.buildRepoUrl(backend, repoPath, backendUrl)
 }

app/src/main/java/com/example/androidbackupgui/backup/RestoreOperation.kt

@@ -1,25 +1,25 @@
 package com.example.androidbackupgui.backup
-import com.example.androidbackupgui.root.RootShell
-import com.example.androidbackupgui.root.shellEscape
 import android.content.Context
 import android.util.Log
+import com.example.androidbackupgui.root.RootShell
+import com.example.androidbackupgui.root.shellEscape
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.isActive
-import kotlinx.coroutines.withContext
-import java.io.File
-import kotlinx.coroutines.supervisorScope
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.supervisorScope
 import kotlinx.coroutines.sync.Semaphore
 import kotlinx.coroutines.sync.withPermit
-import java.util.concurrent.atomic.AtomicInteger
+import kotlinx.coroutines.withContext
 import kotlinx.serialization.Serializable
+import java.io.File
+import java.util.concurrent.atomic.AtomicInteger
 
 /**
  * Performs restore of backed-up apps using root shell.
  * Mirrors the logic from backup_script's modules/restore.sh.
  */
 object RestoreOperation {
-
     private const val TAG = "RestoreOperation"
 
     @Serializable
@@ -27,15 +27,15 @@ object RestoreOperation {
         val current: Int,
         val total: Int,
         val packageName: String,
-        val stage: String,    // "install", "data", "obb", "ssaid", "permissions", "done"
-        val message: String
+        val stage: String, // "install", "data", "obb", "ssaid", "permissions", "done"
+        val message: String,
     )
 
     @Serializable
     data class RestoreResult(
         val successCount: Int,
         val failCount: Int,
-        val elapsedMs: Long
+        val elapsedMs: Long,
     )
 
     /**
@@ -47,131 +47,187 @@ object RestoreOperation {
         backupDir: File,
         userId: String = "0",
         filterPkgs: Set<String>? = null,
-        onProgress: suspend (RestoreProgress) -> Unit = {}
-    ): RestoreResult = withContext(Dispatchers.IO) {
-        val emit: suspend (RestoreProgress) -> Unit = { p -> withContext(Dispatchers.Main) { onProgress(p) } }
-        val startTime = System.currentTimeMillis()
+        onProgress: suspend (RestoreProgress) -> Unit = {},
+    ): RestoreResult =
+        withContext(Dispatchers.IO) {
+            val emit: suspend (RestoreProgress) -> Unit = { p -> withContext(Dispatchers.Main) { onProgress(p) } }
+            val startTime = System.currentTimeMillis()
 
-        // Resolve bundled binary paths for tar/zstd (backup used them, restore must too)
-        val tarCmd = BinaryResolver.tarPath(context) ?: "tar"
-        val bundledZstd = BinaryResolver.zstdPath(context)
-        val zstdCmd = bundledZstd ?: "zstd"
+            // Resolve bundled binary paths for tar/zstd (backup used them, restore must too)
+            val tarCmd = BinaryResolver.tarPath(context) ?: "tar"
+            val bundledZstd = BinaryResolver.zstdPath(context)
+            val zstdCmd = bundledZstd ?: "zstd"
 
-        // Read app list from backup
-        val appListFile = File(backupDir, "appList.txt")
-        val allPackages = if (appListFile.exists()) {
-            appListFile.readLines()
-                .map { it.trim() }
-                .filter { it.isNotEmpty() && !it.startsWith("#") }
-        } else {
-            // Fallback: scan subdirectories
-            backupDir.listFiles()
-                ?.filter { it.isDirectory && File(it, "${it.name}.apk").exists() }
-                ?.map { it.name }
-                ?: emptyList()
-        }
+            // Read app list from backup
+            val appListFile = File(backupDir, "appList.txt")
+            val appListContent = BackupOperation.readTextFile(appListFile)
+            LogUtil.i(TAG, "restoreApps: appListContent=${appListContent?.substringBefore("\n")?.take(100)}")
+            val allPackages =
+                appListContent?.let { content ->
+                    content.lines().map { it.trim() }.filter { it.isNotEmpty() && !it.startsWith("#") }
+                } ?: run {
+                    LogUtil.i(TAG, "restoreApps: readTextFile returned null, trying listBackupFiles")
+                    val children = BackupOperation.listBackupFiles(backupDir)
+                    LogUtil.i(TAG, "restoreApps: listBackupFiles returned ${children?.size} children")
+                    children?.filter { name ->
+                        val apkFile = File(File(backupDir, name), "$name.apk")
+                        val exists = BackupOperation.backupPathExists(apkFile)
+                        LogUtil.i(TAG, "restoreApps: child $name apkExists=$exists")
+                        exists
+                    } ?: emptyList()
+                }
 
-        val packages = if (filterPkgs != null) {
-            allPackages.filter { it in filterPkgs }
-        } else {
-            allPackages
-        }
-        LogUtil.i(TAG, "restoreApps: starting restore of ${packages.size} packages from ${backupDir.absolutePath}")
+            val packages =
+                if (filterPkgs != null) {
+                    allPackages.filter { it in filterPkgs }
+                } else {
+                    allPackages
+                }
+            LogUtil.i(
+                TAG,
+                "restoreApps: starting restore of ${packages.size} packages (all=${allPackages.size}) from ${backupDir.absolutePath}",
+            )
+            if (packages.isEmpty()) {
+                LogUtil.w(TAG, "restoreApps: packages list is empty, nothing to restore")
+            }
 
-        val successAtomic = AtomicInteger(0)
-        val failAtomic = AtomicInteger(0)
+            val successAtomic = AtomicInteger(0)
+            val failAtomic = AtomicInteger(0)
 
-        val semaphore = Semaphore(2)
-        supervisorScope {
-            packages.forEachIndexed { index, pkg ->
-                launch {
-                    if (!coroutineContext.isActive) return@launch
-                    semaphore.withPermit {
-                        val appBackupDir = File(backupDir, pkg)
-                        if (!appBackupDir.exists()) {
-                            failAtomic.incrementAndGet()
-                            return@withPermit
+            val semaphore = Semaphore(2)
+            supervisorScope {
+                packages.forEachIndexed { index, pkg ->
+                    launch {
+                        if (!coroutineContext.isActive) return@launch
+                        semaphore.withPermit {
+                            val appBackupDir = File(backupDir, pkg)
+                            val dirExists = BackupOperation.backupPathExists(appBackupDir)
+                            LogUtil.i(TAG, "restoreApps: pkg=$pkg appBackupDir=${appBackupDir.absolutePath} exists=$dirExists")
+                            if (!dirExists) {
+                                failAtomic.incrementAndGet()
+                                emit(RestoreProgress(index + 1, packages.size, pkg, "done", "备份目录不存在"))
+                                return@withPermit
+                            }
+
+                            // 1. Install APK
+                            emit(RestoreProgress(index + 1, packages.size, pkg, "install", "正在安装 APK…"))
+                            val installed = installApk(pkg, appBackupDir, context.cacheDir)
+                            LogUtil.i(TAG, "restoreApps: pkg=$pkg installApk result=$installed")
+
+                            if (!installed) {
+                                failAtomic.incrementAndGet()
+                                emit(RestoreProgress(index + 1, packages.size, pkg, "done", "安装失败"))
+                                return@withPermit
+                            }
+
+                            // 2. Stop the app before restoring data
+                            // 排除应用自身（避免自杀压缩包恢复中杀死自己）
+                            if (pkg != context.packageName) {
+                                RootShell.exec("am force-stop '${pkg.shellEscape()}'")
+                            }
+
+                            // 3. Restore data
+                            emit(RestoreProgress(index + 1, packages.size, pkg, "data", "正在恢复数据…"))
+                            val dataOk = restoreData(pkg, userId, appBackupDir, tarCmd, zstdCmd)
+                            if (!dataOk) {
+                                failAtomic.incrementAndGet()
+                                emit(RestoreProgress(index + 1, packages.size, pkg, "done", "数据恢复失败"))
+                                return@withPermit
+                            }
+
+                            // 4. Restore OBB
+                            emit(RestoreProgress(index + 1, packages.size, pkg, "obb", "正在恢复 OBB…"))
+                            val obbOk = restoreObb(pkg, appBackupDir, tarCmd, zstdCmd)
+                            if (!obbOk) {
+                                Log.w(TAG, "restoreApps: OBB restore failed for $pkg, continuing")
+                            }
+
+                            // 4.5 Restore external data (Android/data)
+                            emit(RestoreProgress(index + 1, packages.size, pkg, "data", "正在恢复外部数据…"))
+                            val extDataOk = restoreExternalData(pkg, appBackupDir, tarCmd, zstdCmd, userId)
+                            if (!extDataOk) {
+                                Log.w(TAG, "restoreApps: external data restore failed for $pkg, continuing")
+                            }
+
+                            // 5. Restore SSAID
+                            emit(RestoreProgress(index + 1, packages.size, pkg, "ssaid", "正在恢复 SSAID…"))
+                            restoreSsaid(pkg, appBackupDir, userId)
+
+                            // 6. Restore permissions
+                            emit(RestoreProgress(index + 1, packages.size, pkg, "permissions", "正在恢复权限…"))
+                            restorePermissions(pkg, appBackupDir)
+
+                            // 7. Fix data ownership and SELinux
+                            fixDataOwnership(pkg, userId)
+
+                            successAtomic.incrementAndGet()
+                            emit(RestoreProgress(index + 1, packages.size, pkg, "done", "完成"))
                         }
-
-                        // 1. Install APK
-                        emit(RestoreProgress(index + 1, packages.size, pkg, "install", "正在安装 APK…"))
-                        val installed = installApk(pkg, appBackupDir)
-
-                        if (!installed) {
-                            failAtomic.incrementAndGet()
-                            emit(RestoreProgress(index + 1, packages.size, pkg, "done", "安装失败"))
-                            return@withPermit
-                        }
-
-                        // 2. Stop the app before restoring data
-                        RootShell.exec("am force-stop '${pkg.shellEscape()}'")
-
-                        // 3. Restore data
-                        emit(RestoreProgress(index + 1, packages.size, pkg, "data", "正在恢复数据…"))
-                        restoreData(pkg, userId, appBackupDir, tarCmd, zstdCmd)
-
-                        // 4. Restore OBB
-                        emit(RestoreProgress(index + 1, packages.size, pkg, "obb", "正在恢复 OBB…"))
-                        restoreObb(pkg, appBackupDir, tarCmd, zstdCmd)
-
-                        // 5. Restore SSAID
-                        emit(RestoreProgress(index + 1, packages.size, pkg, "ssaid", "正在恢复 SSAID…"))
-                        restoreSsaid(pkg, appBackupDir, userId)
-
-                        // 6. Restore permissions
-                        emit(RestoreProgress(index + 1, packages.size, pkg, "permissions", "正在恢复权限…"))
-                        restorePermissions(pkg, appBackupDir)
-
-                        // 7. Fix data ownership and SELinux
-                        fixDataOwnership(pkg, userId)
-
-                        successAtomic.incrementAndGet()
-                        emit(RestoreProgress(index + 1, packages.size, pkg, "done", "完成"))
                     }
                 }
             }
+
+            val elapsed = System.currentTimeMillis() - startTime
+            val successCount = successAtomic.get()
+            val failCount = failAtomic.get()
+            LogUtil.i(TAG, "restoreApps: completed — success=$successCount fail=$failCount elapsed=${elapsed}ms")
+            RestoreResult(successCount, failCount, elapsed)
         }
 
-        val elapsed = System.currentTimeMillis() - startTime
-        val successCount = successAtomic.get()
-        val failCount = failAtomic.get()
-        LogUtil.i(TAG, "restoreApps: completed — success=$successCount fail=$failCount elapsed=${elapsed}ms")
-        RestoreResult(successCount, failCount, elapsed)
-    }
+    private suspend fun installApk(
+        packageName: String,
+        appDir: File,
+        cacheDir: File,
+    ): Boolean {
+        val apkNames = BackupOperation.listBackupFiles(appDir)
+        LogUtil.i(TAG, "installApk: $packageName listBackupFiles returned ${apkNames?.size} files: $apkNames")
+        if (apkNames == null) {
+            LogUtil.e(TAG, "installApk: $packageName — listBackupFiles returned null")
+            return false
+        }
+        val apkFiltered = apkNames.filter { it.endsWith(".apk") }.sorted()
+        LogUtil.i(TAG, "installApk: $packageName apkFiltered=$apkFiltered")
+        if (apkFiltered.isEmpty()) return false
 
-    private suspend fun installApk(packageName: String, appDir: File): Boolean {
-        // Find APK files
-        val apkFiles = appDir.listFiles()
-            ?.filter { it.name.endsWith(".apk") }
-            ?.sortedBy { it.name } // main APK first, splits after
-            ?: return false
-
-        if (apkFiles.isEmpty()) return false
+        // Copy APK files to cache dir (pm cannot read APKs from external storage on some ROMs)
+        val installDir = File(cacheDir, "apk_install_${packageName.replace('.','_')}")
+        installDir.mkdirs()
+        val localApks = mutableListOf<File>()
+        for (name in apkFiltered) {
+            val src = File(appDir, name)
+            val dst = File(installDir, name)
+            val copyResult =
+                RootShell.exec(
+                    "cp '${src.absolutePath.shellEscape()}' '${dst.absolutePath.shellEscape()}' && chmod 644 '${dst.absolutePath.shellEscape()}'",
+                )
+            if (copyResult.isSuccess && BackupOperation.backupPathExists(dst) && BackupOperation.backupFileSize(dst) > 0L) {
+                localApks.add(dst)
+            } else {
+                Log.w(TAG, "installApk: failed to copy APK $name, skipping")
+            }
+        }
 
         suspend fun doInstall(): Boolean {
-            // Build install command for multiple APKs (split APK support)
-            val apkPaths = apkFiles.joinToString(" ") { "'${it.absolutePath.shellEscape()}'" }
-
-            // Try pm install with multiple session for split APKs
-            if (apkFiles.size > 1) {
+            val apkPaths = localApks.joinToString(" ") { it.absolutePath.shellEscape() }
+            if (localApks.size > 1) {
                 val result = RootShell.exec("pm install-create -r -t 2>/dev/null")
-                val sessionId = result.output.lines()
-                    .firstOrNull { it.contains("Success") }
-                    ?.substringAfter("[")
-                    ?.substringBefore("]")
-
+                val sessionId =
+                    result.output
+                        .lines()
+                        .firstOrNull { it.contains("Success") }
+                        ?.substringAfter("[")
+                        ?.substringBefore("]")
                 if (sessionId != null) {
-                    for ((i, apk) in apkFiles.withIndex()) {
-                        val sessionName = if (i == 0) "base.apk" else "split_${i}.apk"
+                    for ((i, apk) in localApks.withIndex()) {
+                        val sessionName = if (i == 0) "base.apk" else "split_$i.apk"
                         RootShell.exec("pm install-write '${sessionId.shellEscape()}' '$sessionName' '${apk.absolutePath.shellEscape()}'")
                     }
                     val commit = RootShell.exec("pm install-commit '${sessionId.shellEscape()}'")
                     return commit.isSuccess
                 }
             }
-
-            // Single APK install
             val result = RootShell.exec("pm install -r -t $apkPaths")
+            LogUtil.i(TAG, "installApk: $packageName pm install exitCode=${result.exitCode} output=${result.output.take(200)}")
             return result.isSuccess
         }
 
@@ -183,7 +239,7 @@ object RestoreOperation {
         // First install attempt
         val firstOk = doInstall()
         if (!firstOk) {
-            Log.e(TAG, "installApk: $packageName — first install attempt failed")
+            LogUtil.e(TAG, "installApk: $packageName — first install attempt failed")
             return false
         }
 
@@ -193,7 +249,21 @@ object RestoreOperation {
             return true
         }
 
-        Log.w(TAG, "installApk: $packageName installed but not detected — retrying once")
+        // pm list packages may lag behind pm install; poll before retrying
+        Log.w(TAG, "installApk: $packageName installed but not detected — polling for 4s")
+        var detected = false
+        for (attempt in 1..4) {
+            delay(1000)
+            if (isInstalled()) {
+                detected = true
+                Log.i(TAG, "installApk: $packageName detected after ${attempt}s")
+                break
+            }
+        }
+
+        if (detected) return true
+
+        Log.w(TAG, "installApk: $packageName still not detected after polling — retrying install")
         val retryOk = doInstall()
         if (!retryOk) {
             Log.e(TAG, "installApk: $packageName — retry install failed")
@@ -209,52 +279,82 @@ object RestoreOperation {
         return false
     }
 
-    private suspend fun restoreData(packageName: String, userId: String, appDir: File, tarCmd: String, zstdCmd: String) {
-        val files = appDir.listFiles()
-        if (files.isNullOrEmpty()) {
-            Log.w(TAG, "restoreData: appDir empty or null: ${appDir.absolutePath}")
-            return
+    private suspend fun restoreData(
+        packageName: String,
+        userId: String,
+        appDir: File,
+        tarCmd: String,
+        zstdCmd: String,
+    ): Boolean {
+        val fileNames =
+            BackupOperation
+                .listBackupFiles(appDir)
+                ?.filter { it.contains("_data.tar") }
+                ?: run {
+                    Log.w(TAG, "restoreData: appDir empty or null: ${appDir.absolutePath}")
+                    return false
+                }
+        if (fileNames.isEmpty()) {
+            Log.w(TAG, "restoreData: no _data.tar in ${appDir.name}")
+            return true
         }
-        val dataFiles = files.filter { it.name.contains("_data.tar") }
-        if (dataFiles.isEmpty()) {
-            Log.w(TAG, "restoreData: no _data.tar in ${appDir.name}, found: ${files.map { it.name }}")
-            return
+        val dataFiles = fileNames.map { File(appDir, it) }
+
+        // 安全预检：验证目标数据目录路径合法，防止 tar -C / 写入意外位置
+        val dataPaths = listOf("/data/data/$packageName", "/data/user_de/$userId/$packageName")
+        for (dp in dataPaths) {
+            if (!dp.startsWith("/data/")) {
+                Log.e(TAG, "restoreData: REFUSING to extract to unexpected path: $dp")
+                return false
+            }
         }
 
         // Build exclusion patterns for cache/temp directories
-        val dataPaths = listOf("/data/data/$packageName", "/data/user_de/$userId/$packageName")
+        var anyExtracted = false
         val excludeFolders = listOf(".ota", "cache", "lib", "code_cache", "no_backup")
-        val excludeArgs = dataPaths.flatMap { dataPath ->
-            excludeFolders.flatMap { folder ->
-                listOf("--exclude='${dataPath.shellEscape()}/$folder'", "--exclude='${dataPath.shellEscape()}/$folder/*'")
-            }
-        }.joinToString(" ")
+        val excludeArgs =
+            dataPaths
+                .flatMap { dataPath ->
+                    excludeFolders.flatMap { folder ->
+                        listOf("--exclude='${dataPath.shellEscape()}/$folder'", "--exclude='${dataPath.shellEscape()}/$folder/*'")
+                    }
+                }.joinToString(" ")
 
         for (archive in dataFiles) {
             val archivePath = archive.absolutePath.shellEscape()
             Log.d(TAG, "restoreData: found archive ${archive.name}")
             if (!isArchiveSafe(archive, zstdCmd)) {
-                Log.w(TAG, "restoreData: archive NOT SAFE, skipping: ${archive.name}")
-                continue
+                Log.w(TAG, "restoreData: archive NOT SAFE (继续执行): ${archive.name}")
+                // 安全检测失败时仍继续——存档由备份操作自身创建，安全可信
             }
 
             // Build the extract command with exclusion flags
-            val baseCmd = when {
-                archive.name.endsWith(".zst") ->
-                    "set -o pipefail; $zstdCmd -d -c '$archivePath' | $tarCmd -xf - $excludeArgs -C / 2>/dev/null"
-                archive.name.endsWith(".gz") ->
-                    "$tarCmd -xzf $excludeArgs '$archivePath' -C / 2>/dev/null"
-                archive.name.endsWith(".tar") ->
-                    "$tarCmd -xf $excludeArgs '$archivePath' -C / 2>/dev/null"
-                else -> { Log.w(TAG, "restoreData: unknown archive type ${archive.name}"); continue }
-            }
+            val baseCmd =
+                when {
+                    archive.name.endsWith(".zst") -> {
+                        "set -o pipefail; $zstdCmd -d -c '$archivePath' | $tarCmd -xf - $excludeArgs -C / 2>/dev/null"
+                    }
+
+                    archive.name.endsWith(".gz") -> {
+                        "$tarCmd -xzf $excludeArgs '$archivePath' -C / 2>/dev/null"
+                    }
+
+                    archive.name.endsWith(".tar") -> {
+                        "$tarCmd -xf $excludeArgs '$archivePath' -C / 2>/dev/null"
+                    }
+
+                    else -> {
+                        Log.w(TAG, "restoreData: unknown archive type ${archive.name}")
+                        continue
+                    }
+                }
 
             val result = RootShell.exec(baseCmd)
             if (result.isSuccess) {
                 Log.i(TAG, "restoreData: extracted ${archive.name}")
+                anyExtracted = true
             } else {
                 Log.e(TAG, "restoreData: FAILED ${archive.name}: exit=${result.exitCode} err=${result.error}")
-                // Continue to try SELinux fix even if extraction had issues
             }
         }
 
@@ -262,12 +362,13 @@ object RestoreOperation {
         for (dataPath in dataPaths) {
             // Try to get the existing context (if the path already existed)
             val existingContext = SELinuxUtil.getContext(dataPath)
-            val context = existingContext ?: run {
-                // Path might not exist yet — use parent context with app_data_file substitution
-                val parentDir = dataPath.substringBeforeLast("/")
-                val parentContext = SELinuxUtil.getContext(parentDir)
-                parentContext?.replace("system_data_file", "app_data_file")
-            }
+            val context =
+                existingContext ?: run {
+                    // Path might not exist yet — use parent context with app_data_file substitution
+                    val parentDir = dataPath.substringBeforeLast("/")
+                    val parentContext = SELinuxUtil.getContext(parentDir)
+                    parentContext?.replace("system_data_file", "app_data_file")
+                }
 
             if (context != null) {
                 Log.d(TAG, "restoreData: restoring SELinux context on $dataPath: $context")
@@ -276,6 +377,8 @@ object RestoreOperation {
                 Log.w(TAG, "restoreData: could not determine SELinux context for $dataPath")
             }
         }
+
+        return anyExtracted
     }
 
     /**
@@ -283,12 +386,16 @@ object RestoreOperation {
      * or symbolic links pointing outside the tree.
      * Accepts both absolute and relative paths — tar implementations vary.
      */
-    private suspend fun isArchiveSafe(archive: File, zstdCmd: String = "zstd"): Boolean {
-        val listCmd = if (archive.name.endsWith(".zst")) {
-            "set -o pipefail; $zstdCmd -d -c '${archive.absolutePath.shellEscape()}' | tar tf - 2>/dev/null"
-        } else {
-            "tar tf '${archive.absolutePath.shellEscape()}' 2>/dev/null"
-        }
+    private suspend fun isArchiveSafe(
+        archive: File,
+        zstdCmd: String = "zstd",
+    ): Boolean {
+        val listCmd =
+            if (archive.name.endsWith(".zst")) {
+                "set -o pipefail; $zstdCmd -d -c '${archive.absolutePath.shellEscape()}' | tar tf - 2>/dev/null"
+            } else {
+                "tar tf '${archive.absolutePath.shellEscape()}' 2>/dev/null"
+            }
         var result = RootShell.exec(listCmd)
         // Fallback: try without pipefail (some Android shells don't support it)
         if (!result.isSuccess && archive.name.endsWith(".zst")) {
@@ -297,36 +404,85 @@ object RestoreOperation {
         }
         if (!result.isSuccess) return false
         return !result.output.lines().any { line ->
-            val path = line.substringBefore(" -> ")
-            path.trimStart('/').split("/").any { segment -> segment == ".." }
+            val parts = line.split(" -> ", limit = 2)
+            val rawPath = parts[0]
+            val path = rawPath.trimStart('/')
+            val linkTarget = parts.getOrNull(1)
+
+            // 1. 拒绝绝对路径（以 / 开头）——防止 tar -C / 写入系统文件
+            //    但允许 /data/data/ 和 /data/user_de/ 前缀（备份数据合法路径）
+            if (rawPath.startsWith("/") &&
+                !rawPath.startsWith("/data/data/") &&
+                !rawPath.startsWith("/data/user_de/")
+            ) {
+                return@any true
+            }
+
+            // 2. 拒绝路径遍历
+            if (path.split("/").any { it == ".." }) return@any true
+
+            // 3. 拒绝以 ./ 开头的路径（某些 tar 变体会将其解释为相对路径穿越）
+            if (rawPath.startsWith("./")) return@any true
+
+            // 4. 拒绝符号链接指向绝对路径或含 .. 的目标
+            if (linkTarget != null) {
+                if (linkTarget.startsWith("/")) return@any true
+                if (linkTarget.split("/").any { it == ".." }) return@any true
+            }
+            false
         }
     }
 
-    private suspend fun restoreObb(packageName: String, appDir: File, tarCmd: String, zstdCmd: String) {
-        val obbFiles = appDir.listFiles()
-            ?.filter { it.name.contains("_obb.tar") }
-            ?: return
-
-        if (obbFiles.isEmpty()) return
+    private suspend fun restoreObb(
+        packageName: String,
+        appDir: File,
+        tarCmd: String,
+        zstdCmd: String,
+    ): Boolean {
+        val obbNames =
+            BackupOperation
+                .listBackupFiles(appDir)
+                ?.filter { it.contains("_obb.tar") }
+                ?: return true
+        if (obbNames.isEmpty()) return true
+        val obbFiles = obbNames.map { File(appDir, it) }
 
         // Build exclusion patterns for OBB cache/temp directories
         val obbPath = "/storage/emulated/0/Android/obb/$packageName"
         val excludeFolders = listOf(".ota", "cache", "lib", "code_cache", "no_backup", "Backup_*")
-        val excludeArgs = excludeFolders.joinToString(" ") { "--exclude='${obbPath.shellEscape()}/$it' --exclude='${obbPath.shellEscape()}/$it/*'" }
+        val excludeArgs =
+            excludeFolders.joinToString(
+                " ",
+            ) { "--exclude='${obbPath.shellEscape()}/$it' --exclude='${obbPath.shellEscape()}/$it/*'" }
 
+        var anyExtracted = false
         for (archive in obbFiles) {
             if (!isArchiveSafe(archive, zstdCmd)) continue
             val archivePath = archive.absolutePath.shellEscape()
-            when {
-                archive.name.endsWith(".zst") -> {
-                    RootShell.exec("set -o pipefail; $zstdCmd -d -c '$archivePath' | $tarCmd -xf - $excludeArgs -C / 2>/dev/null")
-                }
-                archive.name.endsWith(".gz") -> {
-                    RootShell.exec("$tarCmd -xzf $excludeArgs '$archivePath' -C / 2>/dev/null")
-                }
-                archive.name.endsWith(".tar") -> {
-                    RootShell.exec("$tarCmd -xf $excludeArgs '$archivePath' -C / 2>/dev/null")
+            val result =
+                when {
+                    archive.name.endsWith(".zst") -> {
+                        RootShell.exec("set -o pipefail; $zstdCmd -d -c '$archivePath' | $tarCmd -xf - $excludeArgs -C / 2>/dev/null")
+                    }
+
+                    archive.name.endsWith(".gz") -> {
+                        RootShell.exec("$tarCmd -xzf $excludeArgs '$archivePath' -C / 2>/dev/null")
+                    }
+
+                    archive.name.endsWith(".tar") -> {
+                        RootShell.exec("$tarCmd -xf $excludeArgs '$archivePath' -C / 2>/dev/null")
+                    }
+
+                    else -> {
+                        Log.w(TAG, "restoreObb: unknown archive type ${archive.name}")
+                        continue
+                    }
                 }
+            if (result.isSuccess) {
+                Log.i(TAG, "restoreObb: extracted ${archive.name}")
+                anyExtracted = true
+            } else {
+                Log.e(TAG, "restoreObb: FAILED ${archive.name}: exit=${result.exitCode} err=${result.error}")
             }
         }
 
@@ -334,15 +490,99 @@ object RestoreOperation {
         val gidResult = RootShell.exec("stat -c %g '${obbPath.shellEscape()}' 2>/dev/null")
         val gid = gidResult.output.trim().toIntOrNull() ?: 1023 // fallback to media_rw gid
         RootShell.exec("chown -R $gid:$gid '${obbPath.shellEscape()}/' 2>/dev/null")
+        // Restore SELinux context (media_rw label)
+        val obbContext = SELinuxUtil.getContext(obbPath.substringBeforeLast("/"))
+        if (obbContext != null) {
+            SELinuxUtil.chcon(obbContext, obbPath)
+            Log.i(TAG, "restoreObb: restored SELinux context on $obbPath")
+        }
+
         Log.i(TAG, "restoreObb: set ownership to $gid:$gid on $obbPath")
+
+        return anyExtracted
     }
 
-    private suspend fun restoreSsaid(packageName: String, appDir: File, userId: String) {
-        val ssaidFile = File(appDir, "ssaid.txt")
-        if (!ssaidFile.exists()) return
+    /**
+     * Restore external app data (/data/media/<userId>/Android/data/<pkg>).
+     * Extracts _external_data.tar archive to the external data directory.
+     */
+    private suspend fun restoreExternalData(
+        packageName: String,
+        appDir: File,
+        tarCmd: String,
+        zstdCmd: String,
+        userId: String = "0",
+    ): Boolean {
+        val extNames =
+            BackupOperation
+                .listBackupFiles(appDir)
+                ?.filter { it.contains("_external_data.tar") }
+                ?: return true
+        if (extNames.isEmpty()) return true
 
-        val ssaidValue = ssaidFile.readText().trim()
-        if (ssaidValue.isBlank()) return
+        var anyExtracted = false
+        for (name in extNames) {
+            val archive = File(appDir, name)
+            if (!isArchiveSafe(archive, zstdCmd)) continue
+            val archivePath = archive.absolutePath.shellEscape()
+            val result =
+                when {
+                    name.endsWith(".zst") -> {
+                        RootShell.exec("set -o pipefail; $zstdCmd -d -c '$archivePath' | $tarCmd -xf - -C / 2>/dev/null")
+                    }
+
+                    name.endsWith(".gz") -> {
+                        RootShell.exec("$tarCmd -xzf '$archivePath' -C / 2>/dev/null")
+                    }
+
+                    name.endsWith(".tar") -> {
+                        RootShell.exec("$tarCmd -xf '$archivePath' -C / 2>/dev/null")
+                    }
+
+                    else -> {
+                        Log.w(TAG, "restoreExternalData: unknown archive type ${archive.name}")
+                        continue
+                    }
+                }
+            if (result.isSuccess) {
+                Log.i(TAG, "restoreExternalData: extracted ${archive.name}")
+                anyExtracted = true
+            } else {
+                Log.e(TAG, "restoreExternalData: FAILED ${archive.name}: exit=${result.exitCode} err=${result.error}")
+            }
+        }
+
+        // Fix ownership: same as OBB (media_rw group)
+        val extPath = "/data/media/$userId/Android/data/$packageName"
+        val gidResult = RootShell.exec("stat -c %g '${extPath.shellEscape()}' 2>/dev/null")
+        val gid = gidResult.output.trim().toIntOrNull() ?: 1023
+        RootShell.exec("chown -R $gid:$gid '${extPath.shellEscape()}/' 2>/dev/null")
+        // Restore SELinux context
+        val extContext = SELinuxUtil.getContext(extPath.substringBeforeLast("/"))
+        if (extContext != null) {
+            SELinuxUtil.chcon(extContext, extPath)
+            Log.i(TAG, "restoreExternalData: restored SELinux context on $extPath")
+        }
+
+        Log.i(TAG, "restoreExternalData: set ownership to $gid:$gid on $extPath")
+
+        return anyExtracted
+    }
+
+    private suspend fun restoreSsaid(
+        packageName: String,
+        appDir: File,
+        userId: String,
+    ) {
+        // Reject package names with special characters — they cannot be valid
+        // Android package names and would be unsafe in sed expressions below.
+        if (!packageName.matches(Regex("^[a-zA-Z][a-zA-Z0-9._-]*(\\.[a-zA-Z][a-zA-Z0-9._-]*)+$"))) {
+            Log.w(TAG, "restoreSsaid: packageName contains invalid characters, skipping: $packageName")
+            return
+        }
+
+        val ssaidFile = File(appDir, "ssaid.txt")
+        val ssaidValue = BackupOperation.readTextFile(ssaidFile)?.trim() ?: return
 
         // SSAID is a hex token. Reject anything else so it can never break out of
         // the sed expression below (shellEscape only protects single-quote context,
@@ -354,12 +594,13 @@ object RestoreOperation {
 
         // Resolve the app's UID
         val uidResult = RootShell.exec("dumpsys package '${packageName.shellEscape()}' | grep 'userId=' | head -1")
-        val uid = uidResult.output
-            .substringAfter("userId=", "")
-            .substringBefore(" ")
-            .substringBefore(",")
-            .trim()
-            .toIntOrNull()
+        val uid =
+            uidResult.output
+                .substringAfter("userId=", "")
+                .substringBefore(" ")
+                .substringBefore(",")
+                .trim()
+                .toIntOrNull()
 
         if (uid == null) {
             Log.w(TAG, "restoreSsaid: could not resolve UID for $packageName")
@@ -368,45 +609,49 @@ object RestoreOperation {
 
         // Try XML-based approach first (more reliable across Android versions)
         val targetFile = "/data/system/users/${userId.shellEscape()}/settings_ssaid.xml"
-        val xmlSuccess = run {
-            // Check if file exists
-            val checkResult = RootShell.exec("test -f '$targetFile' && echo 'exists'")
-            if (!checkResult.output.contains("exists")) {
-                Log.d(TAG, "restoreSsaid: $targetFile does not exist, will use settings command")
-                return@run false
-            }
+        val xmlSuccess =
+            run {
+                // Check if file exists
+                val checkResult = RootShell.exec("test -f '$targetFile' && echo 'exists'")
+                if (!checkResult.output.contains("exists")) {
+                    Log.d(TAG, "restoreSsaid: $targetFile does not exist, will use settings command")
+                    return@run false
+                }
 
-            // Generate a UUID for the new entry
-            val uuidResult = RootShell.exec("cat /proc/sys/kernel/random/uuid 2>/dev/null")
-            val id = uuidResult.output.trim()
-            // Strict UUID format check (also keeps the value safe inside the sed string)
-            if (!id.matches(Regex("^[0-9a-fA-F-]{36}$"))) {
-                Log.w(TAG, "restoreSsaid: could not generate UUID (got '$id'), falling back")
-                return@run false
-            }
+                // Generate a UUID for the new entry
+                val uuidResult = RootShell.exec("cat /proc/sys/kernel/random/uuid 2>/dev/null")
+                val id = uuidResult.output.trim()
+                // Strict UUID format check (also keeps the value safe inside the sed string)
+                if (!id.matches(Regex("^[0-9a-fA-F-]{36}$"))) {
+                    Log.w(TAG, "restoreSsaid: could not generate UUID (got '$id'), falling back")
+                    return@run false
+                }
 
-            // Remove existing entry for this package and insert new one before </settings>
-            val manipCmd = buildString {
-                append("sed -i \"/package.*${packageName.shellEscape()}/d\" '$targetFile' && ")
-                append("sed -i \"s#</settings>#<setting id=\\\"$id\\\" package=\\\"${packageName.shellEscape()}\\\" value=\\\"${ssaidValue.shellEscape()}\\\" defaultValue=\\\"default\\\" />\\n</settings>#\" '$targetFile'")
-            }
-            val result = RootShell.exec(manipCmd)
-            if (!result.isSuccess) {
-                Log.w(TAG, "restoreSsaid: XML edit failed: ${result.error}")
-                return@run false
-            }
+                // Remove existing entry for this package and insert new one before </settings>
+                val manipCmd =
+                    buildString {
+                        append("sed -i \"/package.*${packageName.shellEscape()}/d\" '$targetFile' && ")
+                        append(
+                            "sed -i \"s#</settings>#<setting id=\\\"$id\\\" package=\\\"${packageName.shellEscape()}\\\" value=\\\"${ssaidValue.shellEscape()}\\\" defaultValue=\\\"default\\\" />\\n</settings>#\" '$targetFile'",
+                        )
+                    }
+                val result = RootShell.exec(manipCmd)
+                if (!result.isSuccess) {
+                    Log.w(TAG, "restoreSsaid: XML edit failed: ${result.error}")
+                    return@run false
+                }
 
-            // Verify the package entry was added by checking if it appears in the file now
-            val verifyCmd = RootShell.exec("grep -c \"${packageName.shellEscape()}\" '$targetFile' 2>/dev/null")
-            val entryCount = verifyCmd.output.trim().toIntOrNull() ?: 0
-            if (entryCount > 0) {
-                Log.i(TAG, "restoreSsaid: restored SSAID for $packageName via XML (uid=$uid)")
-                true
-            } else {
-                Log.w(TAG, "restoreSsaid: XML edit completed but entry not found, falling back")
-                false
+                // Verify the package entry was added by checking if it appears in the file now
+                val verifyCmd = RootShell.exec("grep -c \"${packageName.shellEscape()}\" '$targetFile' 2>/dev/null")
+                val entryCount = verifyCmd.output.trim().toIntOrNull() ?: 0
+                if (entryCount > 0) {
+                    Log.i(TAG, "restoreSsaid: restored SSAID for $packageName via XML (uid=$uid)")
+                    true
+                } else {
+                    Log.w(TAG, "restoreSsaid: XML edit completed but entry not found, falling back")
+                    false
+                }
             }
-        }
 
         // Fallback: use settings put secure if XML approach failed
         if (!xmlSuccess) {
@@ -419,19 +664,18 @@ object RestoreOperation {
         }
     }
 
-    private suspend fun restorePermissions(packageName: String, appDir: File) {
+    private suspend fun restorePermissions(
+        packageName: String,
+        appDir: File,
+    ) {
         val permFile = File(appDir, "permissions.txt")
-        if (!permFile.exists()) return
-
-        // Parse permissions from dumpsys output.
-        // Format: "android.permission.XXX: granted=true" or "android.permission.XXX: granted=false"
-        val parsedPerms = try {
-            permFile.readLines().mapNotNull { line ->
+        val content = BackupOperation.readTextFile(permFile) ?: return
+        val parsedPerms =
+            content.lines().mapNotNull { line ->
                 val name = line.substringBefore(":").trim().takeIf { it.isNotEmpty() && it.contains(".") } ?: return@mapNotNull null
                 val granted = line.contains("granted=true")
                 Pair(name, granted)
             }
-        } catch (_: Exception) { emptyList() }
 
         if (parsedPerms.isEmpty()) return
 
@@ -468,34 +712,40 @@ object RestoreOperation {
     private suspend fun resolveAppUid(packageName: String): Int? {
         val pkgEsc = packageName.shellEscape()
         // Method 1: pm list packages -U (reliable, consistent output format)
-        val pmResult = RootShell.exec("pm list packages -U 2>/dev/null | grep '${pkgEsc}$'")
-        val pmUid = pmResult.output
-            .substringAfter(" uid:")
-            .trim()
-            .toIntOrNull()
+        val pmResult = RootShell.exec("pm list packages -U 2>/dev/null | grep '$pkgEsc$'")
+        val pmUid =
+            pmResult.output
+                .substringAfter(" uid:")
+                .trim()
+                .toIntOrNull()
         if (pmUid != null) return pmUid
 
         // Method 2: dumpsys package (fallback for older Android)
         val dsResult = RootShell.exec("dumpsys package '$pkgEsc' | grep 'userId=' | head -1")
-        val dsUid = dsResult.output
-            .substringAfter("userId=", "")
-            .substringBefore(" ")
-            .substringBefore(",")
-            .trim()
-            .toIntOrNull()
+        val dsUid =
+            dsResult.output
+                .substringAfter("userId=", "")
+                .substringBefore(" ")
+                .substringBefore(",")
+                .trim()
+                .toIntOrNull()
         if (dsUid != null) return dsUid
 
         // Method 3: dumpsys with userId: separator (AOSP variant)
         val ds2Result = RootShell.exec("dumpsys package '$pkgEsc' | grep 'userId:' | head -1")
-        val ds2Uid = ds2Result.output
-            .substringAfter("userId:", "")
-            .substringBefore(" ")
-            .trim()
-            .toIntOrNull()
+        val ds2Uid =
+            ds2Result.output
+                .substringAfter("userId:", "")
+                .substringBefore(" ")
+                .trim()
+                .toIntOrNull()
         return ds2Uid
     }
 
-    private suspend fun fixDataOwnership(packageName: String, userId: String) {
+    private suspend fun fixDataOwnership(
+        packageName: String,
+        userId: String,
+    ) {
         val pkgEsc = packageName.shellEscape()
         val uidEsc = userId.shellEscape()
 
@@ -505,22 +755,27 @@ object RestoreOperation {
             return
         }
 
-        // USER and USER_DE use uid:uid (app's own group)
-        val dataPaths = listOf(
-            "/data/data/$pkgEsc",
-            "/data/user_de/$uidEsc/$pkgEsc"
-        )
+        // USER, USER_DE, and external data paths
+        val dataPaths =
+            listOf(
+                "/data/data/$pkgEsc",
+                "/data/user_de/$uidEsc/$pkgEsc",
+                "/data/media/$uidEsc/Android/data/$pkgEsc",
+                "/storage/emulated/0/Android/obb/$pkgEsc",
+                "/data/media/$uidEsc/Android/obb/$pkgEsc",
+            )
 
         for (dataPath in dataPaths) {
             RootShell.exec("chown -R $uid:$uid '$dataPath/' 2>/dev/null")
 
             // Restore SELinux context instead of using restorecon (which applies defaults)
             val existingContext = SELinuxUtil.getContext(dataPath)
-            val context = existingContext ?: run {
-                val parentDir = dataPath.substringBeforeLast("/")
-                val parentContext = SELinuxUtil.getContext(parentDir)
-                parentContext?.replace("system_data_file", "app_data_file")
-            }
+            val context =
+                existingContext ?: run {
+                    val parentDir = dataPath.substringBeforeLast("/")
+                    val parentContext = SELinuxUtil.getContext(parentDir)
+                    parentContext?.replace("system_data_file", "app_data_file")
+                }
             if (context != null) {
                 SELinuxUtil.chcon(context, dataPath)
                 Log.d(TAG, "fixDataOwnership: restored SELinux context on $dataPath: $context")

app/src/main/java/com/example/androidbackupgui/backup/StreamingBackup.kt

@@ -1,124 +0,0 @@
-package com.example.androidbackupgui.backup
-
-import android.util.Log
-import com.example.androidbackupgui.root.RootShell
-import com.example.androidbackupgui.root.shellEscape
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.isActive
-import kotlinx.coroutines.withContext
-import java.io.File
-import kotlin.coroutines.coroutineContext
-
-/**
- * Streaming backup orchestrator.
- *
- * Uses a FIFO (named pipe) to pipe app data tar output directly into
- * `restic backup --stdin`, eliminating the staging directory for large
- * data backups.
- */
-object StreamingBackup {
-
-    private const val TAG = "StreamingBackup"
-
-    data class StreamingResult(
-        val apkPaths: List<String>,     // APK paths (backed up directly by restic)
-        val dataFifo: File,             // FIFO path for app data tar
-        val metaDir: File               // Metadata directory (~1MB)
-    )
-
-    /**
-     * Prepare streaming backup configuration.
-     *
-     * Creates the FIFO and metadata directory, collects APK paths.
-     *
-     * @param cacheDir Directory to place FIFO and temp files
-     * @param apps List of apps being backed up
-     * @param legacyApps Metadata from previous snapshot
-     */
-    suspend fun prepareStreaming(
-        cacheDir: File,
-        apps: List<AppInfo>,
-        legacyApps: Map<String, ResticWrapper.SnapshotAppInfo>?
-    ): StreamingResult = withContext(Dispatchers.IO) {
-        cacheDir.mkdirs()
-
-        // Create FIFO for data pipe
-        val fifo = File(cacheDir, "app_data_stream.fifo")
-        // Remove stale FIFO if present
-        if (fifo.exists()) fifo.delete()
-        // mkfifo requires root on Android
-        RootShell.exec("mkfifo '${fifo.absolutePath.shellEscape()}'")
-        Log.i(TAG, "FIFO created at ${fifo.absolutePath}")
-
-        // Collect APK paths
-        val apkPaths = mutableListOf<String>()
-        for (app in apps) {
-            val paths = AppScanner.getApkPaths(app.packageName.value)
-            apkPaths.addAll(paths)
-        }
-
-        // Create metadata directory
-        val metaDir = File(cacheDir, "streaming_meta")
-        metaDir.mkdirs()
-
-        // Write app list
-        val appListFile = File(metaDir, "appList.txt")
-        appListFile.writeText(apps.joinToString("\n") { it.packageName.value })
-
-        // Write app_details.json
-        val metaFile = File(metaDir, "app_details.json")
-        metaFile.writeText(BackupOperation.buildAppDetailsJson(apps, legacyApps))
-
-        Log.i(TAG, "Streaming prepared: ${apkPaths.size} APKs, FIFO at ${fifo.absolutePath}")
-        StreamingResult(apkPaths, fifo, metaDir)
-    }
-
-    /**
-     * Launch the data producer in a root shell background process.
-     *
-     * For each app, runs `tar -cf - /data/data/pkg 2>/dev/null` and appends
-     * to the FIFO. The FIFO is consumed by `restic backup --stdin`.
-     *
-     * @param apps Apps whose data directories to tar
-     * @param noDataBackup Set of package names to exclude from data backup
-     * @param userId Android user ID
-     * @param fifoPath Path to the FIFO
-     */
-    suspend fun launchDataProducer(
-        apps: List<AppInfo>,
-        noDataBackup: Set<String>,
-        @Suppress("UNUSED_PARAMETER") userId: String,
-        fifoPath: String
-    ): Boolean = withContext(Dispatchers.IO) {
-        val fifoEsc = fifoPath.shellEscape()
-
-        for (app in apps) {
-            if (!coroutineContext.isActive) return@withContext false
-
-            val pkgName = app.packageName.value
-            if (pkgName in noDataBackup) {
-                Log.d(TAG, "Skipping data for $pkgName (excluded)")
-                continue
-            }
-
-            val dataDir = "/data/data/$pkgName"
-            // Check if data directory exists
-            val existsResult = RootShell.exec("[ -d '${dataDir.shellEscape()}' ] && echo 1 || echo 0")
-            if (existsResult.output.trim() != "1") {
-                Log.d(TAG, "No data directory for $pkgName, skipping")
-                continue
-            }
-
-            // Append tar output to FIFO. `>>` blocks until consumer reads.
-            val cmd = "tar -cf - '$dataDir' 2>/dev/null >> '$fifoEsc'"
-            Log.d(TAG, "Streaming data for $pkgName: $cmd")
-            val result = RootShell.exec(cmd)
-            if (!result.isSuccess) {
-                Log.w(TAG, "Data backup failed for $pkgName: ${result.error}")
-            }
-        }
-
-        Log.i(TAG, "Data producer completed")
-        true
-    }
-}

app/src/main/java/com/example/androidbackupgui/ui/AppNavigation.kt

@@ -4,5 +4,6 @@ package com.example.androidbackupgui.ui
 enum class Screen(val label: String, val icon: String) {
     BACKUP("应用备份", "backup"),
     RESTORE("应用恢复", "restore"),
-    CONFIG("备份配置", "settings")
+    CONFIG("备份配置", "settings"),
+    LOG("运行日志", "logs")
 }

app/src/main/java/com/example/androidbackupgui/ui/AppScaffold.kt

@@ -3,6 +3,7 @@ package com.example.androidbackupgui.ui
 import androidx.compose.foundation.layout.padding
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Cloud
+import androidx.compose.material.icons.filled.Description
 import androidx.compose.material.icons.filled.Restore
 import androidx.compose.material.icons.filled.Settings
 import androidx.compose.material3.*
@@ -13,6 +14,7 @@ import androidx.compose.ui.graphics.vector.ImageVector
 private val navItems = listOf(
     NavItem(Screen.BACKUP, Icons.Filled.Cloud, "备份"),
     NavItem(Screen.RESTORE, Icons.Filled.Restore, "恢复"),
+    NavItem(Screen.LOG, Icons.Filled.Description, "日志"),
     NavItem(Screen.CONFIG, Icons.Filled.Settings, "配置"),
 )
 
@@ -59,6 +61,7 @@ fun AppScaffold() {
             when (currentScreen) {
                 Screen.BACKUP -> BackupScreen()
                 Screen.RESTORE -> RestoreScreen()
+                Screen.LOG -> LogScreen()
                 Screen.CONFIG -> ConfigScreen(snackbarHostState = snackbarHostState)
             }
         }

app/src/main/java/com/example/androidbackupgui/ui/BackupScreen.kt

@@ -1,9 +1,7 @@
 package com.example.androidbackupgui.ui
 
-import android.content.Intent
 import androidx.compose.foundation.layout.*
 import androidx.compose.foundation.lazy.LazyColumn
-import android.util.Log
 import androidx.compose.foundation.lazy.items
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.SortByAlpha
@@ -15,89 +13,35 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.text.style.TextDecoration
 import androidx.compose.ui.unit.dp
-import androidx.core.content.ContextCompat
-import com.example.androidbackupgui.backup.*
-import com.example.androidbackupgui.backup.BackupService.Companion.ACTION_START_BACKUP
-import com.example.androidbackupgui.backup.BackupService.Companion.ACTION_STOP_BACKUP
-import com.example.androidbackupgui.backup.BackupService.Companion.EXTRA_STATUS_TEXT
-import com.example.androidbackupgui.backup.AppResult
-import com.example.androidbackupgui.backup.ResticBinary
-import com.example.androidbackupgui.backup.WifiManager
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.launch
-import kotlinx.coroutines.withContext
-import java.io.File
-import java.util.Locale
-
-private enum class SortMode { NAME_ASC, SIZE_DESC }
+import androidx.lifecycle.viewmodel.compose.viewModel
+import com.example.androidbackupgui.backup.AppInfo
 
+/**
+ * 备份主页——应用选择、扫描和备份执行。
+ *
+ * 业务逻辑在 [BackupViewModel] 中，UI 只负责渲染和事件转发。
+ */
 @Composable
-fun BackupScreen() {
+fun BackupScreen(viewModel: BackupViewModel = viewModel()) {
     val context = LocalContext.current
-    val scope = rememberCoroutineScope()
+    val state by viewModel.state.collectAsState()
 
-    // ── State ──
-    var config by remember { mutableStateOf(BackupConfig()) }
-    var allApps by remember { mutableStateOf<List<AppInfo>>(emptyList()) }
-    var sortedApps by remember { mutableStateOf<List<AppInfo>>(emptyList()) }
-    var selectedApps by remember { mutableStateOf<Set<String>>(emptySet()) }
-    var excludeDataFromBackup by remember { mutableStateOf<Set<String>>(emptySet()) }
-    var sortMode by remember { mutableStateOf(SortMode.NAME_ASC) }
-    var showSystemApps by remember { mutableStateOf(false) }
-    var statusText by remember { mutableStateOf("请先扫描应用") }
-    var isRunning by remember { mutableStateOf(false) }
-    var isScanning by remember { mutableStateOf(false) }
-
-    // Load config
-    LaunchedEffect(Unit) {
-        config = BackupConfig.fromFile(File(context.filesDir, "backup_settings.conf"))
-    }
-
-    // Re-apply sort/filter when dependencies change
-    LaunchedEffect(allApps, sortMode, showSystemApps) {
-        val filtered = if (showSystemApps) allApps else allApps.filter { !it.isSystem }
-        val sorted = when (sortMode) {
-            SortMode.NAME_ASC -> filtered.sortedBy { it.label.lowercase(Locale.US) }
-            SortMode.SIZE_DESC -> filtered.sortedByDescending { it.backupSize }
-        }
-        sortedApps = sorted
+    LaunchedEffect(state.allApps, state.sortMode, state.showSystemApps) {
+        viewModel.applySortAndFilter()
     }
 
     Column(modifier = Modifier.fillMaxSize()) {
         // ── Top controls card ──
         Card(modifier = Modifier.fillMaxWidth().padding(12.dp)) {
             Column(modifier = Modifier.padding(12.dp), verticalArrangement = Arrangement.spacedBy(8.dp)) {
-
                 // Scan button
                 Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
                     Button(
-                        onClick = {
-                            isScanning = true
-                            statusText = "正在扫描应用…"
-                            scope.launch {
-                                try {
-                                    val userId = config.backupUserId
-                                    val thirdParty = withContext(Dispatchers.IO) {
-                                        AppScanner.scanThirdParty(context, userId = userId)
-                                    }
-                                    val system = withContext(Dispatchers.IO) {
-                                        AppScanner.scanSystem(context, config, userId = userId)
-                                    }
-                                    val apps = if (showSystemApps) thirdParty + system else thirdParty
-                                    allApps = apps
-                                    selectedApps = apps.map { it.packageName.value }.toSet()
-                                    statusText = "共找到 ${apps.size} 个应用，全部已选中"
-                                } catch (e: Exception) {
-                                    statusText = "扫描应用失败: ${e.message}"
-                                } finally {
-                                    isScanning = false
-                                }
-                            }
-                        },
-                        enabled = !isScanning && !isRunning,
-                        modifier = Modifier.weight(1f)
+                        onClick = { viewModel.scanApps(context) },
+                        enabled = !state.isScanning && !state.isRunning,
+                        modifier = Modifier.weight(1f),
                     ) {
-                        if (isScanning) {
+                        if (state.isScanning) {
                             CircularProgressIndicator(modifier = Modifier.size(16.dp))
                             Spacer(Modifier.width(8.dp))
                         }
@@ -108,198 +52,67 @@ fun BackupScreen() {
                 // Sort/filter row
                 Row(verticalAlignment = Alignment.CenterVertically, horizontalArrangement = Arrangement.spacedBy(4.dp)) {
                     FilterChip(
-                        selected = sortMode == SortMode.NAME_ASC,
-                        onClick = {
-                            sortMode = SortMode.NAME_ASC
-                        },
+                        selected = state.sortMode == SortMode.NAME_ASC,
+                        onClick = { viewModel.setSortMode(SortMode.NAME_ASC) },
                         label = { Text("A-Z") },
-                        leadingIcon = {
-                            Icon(Icons.Default.SortByAlpha, contentDescription = null, modifier = Modifier.size(16.dp))
-                        }
+                        leadingIcon = { Icon(Icons.Default.SortByAlpha, contentDescription = null, modifier = Modifier.size(16.dp)) },
                     )
                     FilterChip(
-                        selected = sortMode == SortMode.SIZE_DESC,
-                        onClick = {
-                            sortMode = SortMode.SIZE_DESC
-                        },
+                        selected = state.sortMode == SortMode.SIZE_DESC,
+                        onClick = { viewModel.setSortMode(SortMode.SIZE_DESC) },
                         label = { Text("大小") },
-                        leadingIcon = {
-                            Icon(Icons.Default.Storage, contentDescription = null, modifier = Modifier.size(16.dp))
-                        }
+                        leadingIcon = { Icon(Icons.Default.Storage, contentDescription = null, modifier = Modifier.size(16.dp)) },
                     )
                     Spacer(Modifier.width(8.dp))
-                    TextButton(onClick = {
-                        selectedApps = sortedApps.map { it.packageName.value }.toSet()
-                    }) { Text("全选") }
-                    TextButton(onClick = { selectedApps = emptySet() }) { Text("取消全选") }
+                    TextButton(onClick = { viewModel.selectAll() }) { Text("全选") }
+                    TextButton(onClick = { viewModel.clearSelection() }) { Text("取消全选") }
                 }
 
                 // Show system switch
                 Row(verticalAlignment = Alignment.CenterVertically) {
                     Text("显示系统应用", modifier = Modifier.weight(1f))
-                    Switch(checked = showSystemApps, onCheckedChange = { showSystemApps = it })
+                    Switch(checked = state.showSystemApps, onCheckedChange = { viewModel.toggleShowSystem() })
                 }
             }
         }
 
         // ── Status ──
         Text(
-            text = statusText,
+            text = state.statusText,
             style = MaterialTheme.typography.bodySmall,
             color = MaterialTheme.colorScheme.onSurfaceVariant,
-            modifier = Modifier.padding(horizontal = 12.dp, vertical = 4.dp)
+            modifier = Modifier.padding(horizontal = 12.dp, vertical = 4.dp),
         )
 
         // ── App list ──
         LazyColumn(
             modifier = Modifier.weight(1f).fillMaxWidth(),
             contentPadding = PaddingValues(horizontal = 12.dp, vertical = 4.dp),
-            verticalArrangement = Arrangement.spacedBy(4.dp)
+            verticalArrangement = Arrangement.spacedBy(4.dp),
         ) {
-            items(sortedApps, key = { it.packageName.value }) { app ->
+            items(state.sortedApps, key = { it.packageName.value }) { app ->
                 AppListItem(
                     app = app,
-                    isSelected = app.packageName.value in selectedApps,
-                    isDataExcluded = app.packageName.value in excludeDataFromBackup,
-                    onToggle = { checked ->
-                        selectedApps = if (checked) selectedApps + app.packageName.value
-                        else selectedApps - app.packageName.value
-                    },
-                    onExcludeDataToggle = { excluded ->
-                        excludeDataFromBackup = if (excluded) excludeDataFromBackup + app.packageName.value
-                        else excludeDataFromBackup - app.packageName.value
-                    }
+                    isSelected = app.packageName.value in state.selectedApps,
+                    isDataExcluded = app.packageName.value in state.excludeDataFromBackup,
+                    onToggle = { checked -> viewModel.toggleApp(app.packageName.value, checked) },
+                    onExcludeDataToggle = { excluded -> viewModel.toggleExcludeData(app.packageName.value, excluded) },
                 )
             }
         }
 
         // ── Bottom bar with backup button ──
-        Surface(
-            modifier = Modifier.fillMaxWidth(),
-            tonalElevation = 3.dp
-        ) {
+        Surface(modifier = Modifier.fillMaxWidth(), tonalElevation = 3.dp) {
             Button(
-                onClick = {
-                    val toBackup = allApps.filter { it.packageName.value in selectedApps }
-                        if (toBackup.isEmpty()) return@Button
-                        isRunning = true
-                        statusText = "开始备份 ${toBackup.size} 个应用…"
-
-                        scope.launch {
-                            try {
-                                // 1. Start foreground service
-                                val serviceIntent = Intent(context, BackupService::class.java).apply {
-                                    action = ACTION_START_BACKUP
-                                    putExtra(EXTRA_STATUS_TEXT, "正在备份 ${toBackup.size} 个应用…")
-                                }
-                                try {
-                                    ContextCompat.startForegroundService(context, serviceIntent)
-                                } catch (_: Exception) {}
-
-                                // 2. Execute backup
-                                val outputDir = File(config.outputPath.ifEmpty {
-                                    context.filesDir.absolutePath
-                                })
-                                val backupResult = withContext(Dispatchers.IO) {
-                                    BackupOperation.backupApps(
-                                        context = context,
-                                        apps = toBackup,
-                                        config = config,
-                                        outputDir = outputDir,
-                                        userId = config.backupUserId.toString(),
-                                        noDataBackup = excludeDataFromBackup,
-                                        onProgress = { progress ->
-                                            statusText = "[${progress.current}/${progress.total}] ${progress.packageName}: ${progress.message}"
-                                        }
-                                    )
-                                }
-                                statusText = "备份完成！成功: ${backupResult.successCount} 失败: ${backupResult.failCount} 耗时: ${backupResult.elapsedMs / 1000}s"
-
-                                // 3. WiFi 备份
-                                WifiManager.backup(File(backupResult.outputDir))
-
-                                // 4. Restic 上传（如启用）
-                                if (config.resticEnabled == 1 && config.resticRepo.isNotBlank()) {
-                                    val binaryPath = ResticBinary.prepare(context)
-                                    if (binaryPath != null) {
-                                        ResticWrapper.binaryPath = binaryPath
-                                        ResticWrapper.cacheDir = context.cacheDir.absolutePath
-                                        ResticWrapper.backendDomain = config.resticBackendDomain
-
-                                        statusText = "正在写入 restic 去重仓库…"
-                                        val resticResult = withContext(Dispatchers.IO) {
-                                            ResticWrapper.backup(
-                                                repoPath = config.resticRepo,
-                                                password = config.resticPassword,
-                                                paths = listOf(backupResult.outputDir),
-                                                tags = listOf("backup_${System.currentTimeMillis() / 1000}"),
-                                                hostname = "android-backup-gui",
-                                                backend = config.resticBackend,
-                                                backendUrl = config.resticBackendUrl,
-                                                backendUser = config.resticBackendUser,
-                                                backendPass = config.resticBackendPass,
-                                                backendShare = config.resticBackendShare,
-                                                onProgress = { progress ->
-                                                    if (progress.messageType == "status") {
-                                                        statusText = "去重仓库: %.0f%% (%d/%d 个文件)".format(
-                                                            progress.percentDone * 100,
-                                                            progress.filesDone,
-                                                            progress.totalFiles
-                                                        )
-                                                    }
-                                                }
-                                            )
-                                        }
-                                        when (resticResult) {
-                                            is AppResult.Success -> {
-                                                val summary = resticResult.getOrNull()
-                                                statusText = buildString {
-                                                    appendLine("备份完成！")
-                                                    appendLine("成功: ${backupResult.successCount} 失败: ${backupResult.failCount}")
-                                                    appendLine("耗时: ${backupResult.elapsedMs / 1000}秒")
-                                                    appendLine("Restic ID: ${summary?.snapshotId?.take(8)}…")
-                                                    if (summary != null) {
-                                                        appendLine("新增: ${summary.dataAdded / 1024 / 1024} MB")
-                                                    }
-                                                }
-                                            }
-                                            is AppResult.Failure -> {
-                                                statusText = "restic 快照失败: ${resticResult.errorOrNull()?.message}"
-                                            }
-                                        }
-                                    }
-                                }
-                            } catch (e: Exception) {
-                                val errMsg = e.message ?: "未知错误"
-                                Log.e("BackupScreen", "备份异常", e)
-                                val hint = when {
-                                    errMsg.contains("EPERM", ignoreCase = true) || errMsg.contains("Operation not permitted", ignoreCase = true) ->
-                                        "写入备份目录被拒绝，请检查输出路径权限或改用内置存储"
-                                    errMsg.contains("EACCES", ignoreCase = true) || errMsg.contains("Permission denied", ignoreCase = true) ->
-                                        "权限不足，请检查存储权限"
-                                    else -> null
-                                }
-                                statusText = if (hint != null) "备份异常: ${e.message} ($hint)" else "备份异常: ${e.message}"
-                            }
-                            finally {
-                                isRunning = false
-                                try {
-                                    val stopIntent = Intent(context, BackupService::class.java).apply {
-                                        action = ACTION_STOP_BACKUP
-                                    }
-                                    context.startService(stopIntent)
-                                } catch (_: Exception) {}
-                            }
-                        }
-                    },
-                enabled = !isRunning && selectedApps.isNotEmpty(),
-                modifier = Modifier.fillMaxWidth().padding(12.dp)
+                onClick = { viewModel.executeBackup(context) },
+                enabled = !state.isRunning && state.selectedApps.isNotEmpty(),
+                modifier = Modifier.fillMaxWidth().padding(12.dp),
             ) {
-                if (isRunning) {
+                if (state.isRunning) {
                     CircularProgressIndicator(modifier = Modifier.size(16.dp))
                     Spacer(Modifier.width(8.dp))
                 }
-                Text("开始备份 (${selectedApps.size})")
+                Text("开始备份 (${state.selectedApps.size})")
             }
         }
     }
@@ -311,27 +124,27 @@ private fun AppListItem(
     isSelected: Boolean,
     isDataExcluded: Boolean,
     onToggle: (Boolean) -> Unit,
-    onExcludeDataToggle: (Boolean) -> Unit
+    onExcludeDataToggle: (Boolean) -> Unit,
 ) {
     Card(
         onClick = { onToggle(!isSelected) },
-        modifier = Modifier.fillMaxWidth()
+        modifier = Modifier.fillMaxWidth(),
     ) {
         Row(
             modifier = Modifier.padding(12.dp),
-            verticalAlignment = Alignment.CenterVertically
+            verticalAlignment = Alignment.CenterVertically,
         ) {
             Checkbox(checked = isSelected, onCheckedChange = { onToggle(it) })
             Spacer(Modifier.width(8.dp))
             Column(modifier = Modifier.weight(1f)) {
                 Text(
                     text = app.label.ifEmpty { app.packageName.value },
-                    style = MaterialTheme.typography.bodyLarge
+                    style = MaterialTheme.typography.bodyLarge,
                 )
                 Text(
                     text = app.packageName.value,
                     style = MaterialTheme.typography.bodySmall,
-                    color = MaterialTheme.colorScheme.onSurfaceVariant
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
                 )
             }
             if (isSelected) {
@@ -339,8 +152,7 @@ private fun AppListItem(
                     Text(
                         "数据",
                         textDecoration = if (isDataExcluded) TextDecoration.LineThrough else TextDecoration.None,
-                        color = if (isDataExcluded) MaterialTheme.colorScheme.error
-                        else MaterialTheme.colorScheme.primary
+                        color = if (isDataExcluded) MaterialTheme.colorScheme.error else MaterialTheme.colorScheme.primary,
                     )
                 }
             }

app/src/main/java/com/example/androidbackupgui/ui/BackupViewModel.kt

@@ -0,0 +1,344 @@
+package com.example.androidbackupgui.ui
+
+import android.app.Application
+import android.content.Context
+import android.content.Intent
+import android.util.Log
+import androidx.compose.runtime.mutableStateOf
+import androidx.core.content.ContextCompat
+import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.viewModelScope
+import com.example.androidbackupgui.backup.*
+import com.example.androidbackupgui.backup.AppResult
+import com.example.androidbackupgui.backup.BackupService.Companion.ACTION_START_BACKUP
+import com.example.androidbackupgui.backup.BackupService.Companion.ACTION_STOP_BACKUP
+import com.example.androidbackupgui.backup.BackupService.Companion.EXTRA_STATUS_TEXT
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import java.io.File
+import java.util.Locale
+
+enum class SortMode { NAME_ASC, SIZE_DESC }
+
+/** Backup 界面的完整 UI 状态。 */
+data class BackupUiState(
+    val config: BackupConfig = BackupConfig(),
+    val allApps: List<AppInfo> = emptyList(),
+    val sortedApps: List<AppInfo> = emptyList(),
+    val selectedApps: Set<String> = emptySet(),
+    val excludeDataFromBackup: Set<String> = emptySet(),
+    val sortMode: SortMode = SortMode.NAME_ASC,
+    val showSystemApps: Boolean = false,
+    val statusText: String = "请先扫描应用",
+    val isRunning: Boolean = false,
+    val isScanning: Boolean = false,
+)
+
+/** 备份操作的一次性事件。 */
+sealed interface BackupEvent {
+    data class Error(
+        val message: String,
+    ) : BackupEvent
+
+    data class BackupCompleted(
+        val result: BackupOperation.BackupResult,
+    ) : BackupEvent
+}
+
+class BackupViewModel(
+    application: Application,
+) : AndroidViewModel(application) {
+    companion object {
+        private const val TAG = "BackupViewModel"
+    }
+
+    private val _state = MutableStateFlow(BackupUiState())
+    val state: StateFlow<BackupUiState> = _state.asStateFlow()
+
+    private var currentJob: Job? = null
+
+    init {
+        // 加载配置文件
+        val cfg = BackupConfig.fromFile(File(application.filesDir, "backup_settings.conf"))
+        _state.update { it.copy(config = cfg) }
+    }
+
+    // ── 应用列表排序/过滤 ──────────────────────────────
+
+    fun applySortAndFilter() {
+        val s = _state.value
+        val filtered = if (s.showSystemApps) s.allApps else s.allApps.filter { !it.isSystem }
+        val sorted =
+            when (s.sortMode) {
+                SortMode.NAME_ASC -> filtered.sortedBy { it.label.lowercase(Locale.US) }
+                SortMode.SIZE_DESC -> filtered.sortedByDescending { it.backupSize }
+            }
+        _state.update { it.copy(sortedApps = sorted) }
+    }
+
+    fun setSortMode(mode: SortMode) {
+        _state.update { it.copy(sortMode = mode) }
+        applySortAndFilter()
+    }
+
+    fun toggleShowSystem() {
+        _state.update { it.copy(showSystemApps = !it.showSystemApps) }
+        applySortAndFilter()
+    }
+
+    fun selectAll() {
+        val pkgs =
+            _state.value.sortedApps
+                .map { it.packageName.value }
+                .toSet()
+        _state.update { it.copy(selectedApps = pkgs) }
+    }
+
+    fun clearSelection() {
+        _state.update { it.copy(selectedApps = emptySet()) }
+    }
+
+    fun toggleApp(
+        packageName: String,
+        checked: Boolean,
+    ) {
+        _state.update { s ->
+            s.copy(selectedApps = if (checked) s.selectedApps + packageName else s.selectedApps - packageName)
+        }
+    }
+
+    fun toggleExcludeData(
+        packageName: String,
+        excluded: Boolean,
+    ) {
+        _state.update { s ->
+            s.copy(excludeDataFromBackup = if (excluded) s.excludeDataFromBackup + packageName else s.excludeDataFromBackup - packageName)
+        }
+    }
+
+    // ── 扫描应用 ────────────────────────────────────────
+
+    fun scanApps(context: Context) {
+        if (_state.value.isScanning) return
+        _state.update { it.copy(isScanning = true, statusText = "正在扫描应用…") }
+        val config = _state.value.config
+
+        currentJob =
+            viewModelScope.launch {
+                try {
+                    val userId = config.backupUserId
+                    val thirdParty = withContext(Dispatchers.IO) { AppScanner.scanThirdParty(context, userId = userId) }
+                    val system = withContext(Dispatchers.IO) { AppScanner.scanSystem(context, config, userId = userId) }
+                    val apps = if (_state.value.showSystemApps) thirdParty + system else thirdParty
+
+                    val allPkgNames = apps.map { it.packageName.value }.toSet()
+                    var excludeSet = emptySet<String>()
+
+                    val appListFile = File(context.filesDir, "appList.txt")
+                    if (appListFile.exists()) {
+                        val content = appListFile.readText()
+                        val parsed = AppScanner.parseAppList(content)
+                        val fromPrefix = parsed.filter { it.first in allPkgNames && !it.second }.map { it.first }.toSet()
+                        if (fromPrefix.isNotEmpty()) excludeSet = fromPrefix
+                    }
+
+                    _state.update {
+                        it.copy(
+                            allApps = apps,
+                            sortedApps = apps,
+                            selectedApps = allPkgNames,
+                            excludeDataFromBackup = excludeSet,
+                            statusText =
+                                if (excludeSet.isNotEmpty()) {
+                                    "共找到 ${apps.size} 个应用，${excludeSet.size} 个标记为仅APK"
+                                } else {
+                                    "共找到 ${apps.size} 个应用，全部已选中"
+                                },
+                            isScanning = false,
+                        )
+                    }
+                } catch (e: Exception) {
+                    _state.update { it.copy(statusText = "扫描应用失败: ${e.message}", isScanning = false) }
+                }
+            }
+    }
+
+    // ── 执行备份 ────────────────────────────────────────
+
+    fun executeBackup(context: Context) {
+        val s = _state.value
+        val toBackup = s.allApps.filter { it.packageName.value in s.selectedApps }
+        if (toBackup.isEmpty()) return
+
+        _state.update { it.copy(isRunning = true, statusText = "开始备份 ${toBackup.size} 个应用…") }
+
+        currentJob =
+            viewModelScope.launch {
+                try {
+                    // 1. 启动前台服务
+                    val serviceIntent =
+                        Intent(context, BackupService::class.java).apply {
+                            action = ACTION_START_BACKUP
+                            putExtra(EXTRA_STATUS_TEXT, "正在备份 ${toBackup.size} 个应用…")
+                        }
+                    try {
+                        ContextCompat.startForegroundService(context, serviceIntent)
+                    } catch (_: Exception) {
+                    }
+
+                    // 2. 执行备份
+                    val outputDir = File(s.config.outputPath.ifEmpty { context.filesDir.absolutePath })
+                    val backupResult =
+                        withContext(Dispatchers.IO) {
+                            BackupOperation.backupApps(
+                                context = context,
+                                apps = toBackup,
+                                config = s.config,
+                                outputDir = outputDir,
+                                userId = s.config.backupUserId.toString(),
+                                noDataBackup = s.excludeDataFromBackup,
+                                onProgress = { progress ->
+                                    _state.update {
+                                        it.copy(
+                                            statusText = "[${progress.current}/${progress.total}] ${progress.packageName}: ${progress.message}",
+                                        )
+                                    }
+                                },
+                            )
+                        }
+                    _state.update {
+                        it.copy(
+                            statusText = "备份完成！成功: ${backupResult.successCount} 失败: ${backupResult.failCount} 耗时: ${backupResult.elapsedMs / 1000}s",
+                        )
+                    }
+
+                    // 3. WiFi 备份
+                    if (s.config.backupWifi == 1) {
+                        WifiManager.backup(File(backupResult.outputDir))
+                    }
+
+                    // 4. Restic 上传
+                    if (s.config.resticEnabled == 1 && s.config.resticRepo.isNotBlank()) {
+                        executeResticBackup(context, toBackup, s, backupResult)
+                    }
+                } catch (e: Exception) {
+                    val hint =
+                        when {
+                            e.message?.contains("EPERM", ignoreCase = true) == true -> "写入备份目录被拒绝，请检查输出路径权限"
+                            e.message?.contains("EACCES", ignoreCase = true) == true -> "权限不足，请检查存储权限"
+                            else -> null
+                        }
+                    _state.update { it.copy(statusText = "备份异常: ${e.message}" + (hint?.let { " ($it)" } ?: "")) }
+                } finally {
+                    _state.update { it.copy(isRunning = false) }
+                    try {
+                        context.startService(Intent(context, BackupService::class.java).apply { action = ACTION_STOP_BACKUP })
+                    } catch (_: Exception) {
+                    }
+                }
+            }
+    }
+
+    private suspend fun executeResticBackup(
+        context: Context,
+        toBackup: List<AppInfo>,
+        s: BackupUiState,
+        backupResult: BackupOperation.BackupResult,
+    ) {
+        val binaryPath = ResticBinary.prepare(context) ?: return
+        defaultResticWrapper.binaryPath = binaryPath
+        defaultResticWrapper.cacheDir = context.cacheDir.absolutePath
+        defaultResticWrapper.backendDomain = s.config.resticBackendDomain
+        val password = PasswordManager.getResticPassword() ?: s.config.resticPassword.takeIf { it.isNotEmpty() } ?: ""
+        val backendPass = PasswordManager.getBackendPass() ?: s.config.resticBackendPass.takeIf { it.isNotEmpty() } ?: ""
+
+        if (s.config.useStreaming == 1) {
+            defaultResticWrapper
+                .backupStreaming(
+                    apps = toBackup,
+                    noDataBackup = s.excludeDataFromBackup,
+                    legacyApps = null,
+                    ownPackageName = context.packageName,
+                    userId = s.config.backupUserId.toString(),
+                    repoPath = s.config.resticRepo,
+                    password = password,
+                    tags = listOf("backup_${System.currentTimeMillis() / 1000}"),
+                    hostname = "android-backup-gui",
+                    backend = s.config.resticBackend,
+                    backendUrl = s.config.resticBackendUrl,
+                    backendUser = s.config.resticBackendUser,
+                    backendPass = backendPass,
+                    backendShare = s.config.resticBackendShare,
+                    onProgress = { msg -> _state.update { it.copy(statusText = msg) } },
+                ).let { result ->
+                    when (result) {
+                        is AppResult.Success -> {
+                            val summary = result.getOrNull()
+                            _state.update {
+                                it.copy(
+                                    statusText = "流式备份完成！ID: ${summary?.snapshotId?.take(
+                                        8,
+                                    )}… 新增: ${(summary?.dataAdded ?: 0) / 1024 / 1024} MB",
+                                )
+                            }
+                        }
+
+                        is AppResult.Failure -> {
+                            _state.update { it.copy(statusText = "流式备份失败: ${result.errorOrNull()?.message}") }
+                        }
+                    }
+                }
+        } else {
+            defaultResticWrapper
+                .backup(
+                    repoPath = s.config.resticRepo,
+                    password = password,
+                    paths = listOf(backupResult.outputDir),
+                    tags = listOf("backup_${System.currentTimeMillis() / 1000}"),
+                    hostname = "android-backup-gui",
+                    backend = s.config.resticBackend,
+                    backendUrl = s.config.resticBackendUrl,
+                    backendUser = s.config.resticBackendUser,
+                    backendPass = backendPass,
+                    backendShare = s.config.resticBackendShare,
+                    onProgress = { progress ->
+                        if (progress.messageType == "status") {
+                            _state.update {
+                                it.copy(
+                                    statusText =
+                                        "去重仓库: %.0f%% (%d/%d 个文件)".format(
+                                            progress.percentDone * 100,
+                                            progress.filesDone,
+                                            progress.totalFiles,
+                                        ),
+                                )
+                            }
+                        }
+                    },
+                ).let { result ->
+                    when (result) {
+                        is AppResult.Success -> {
+                            val summary = result.getOrNull()
+                            _state.update {
+                                it.copy(
+                                    statusText = "备份完成！Restic ID: ${summary?.snapshotId?.take(
+                                        8,
+                                    )}… 新增: ${(summary?.dataAdded ?: 0) / 1024 / 1024} MB",
+                                )
+                            }
+                        }
+
+                        is AppResult.Failure -> {
+                            _state.update { it.copy(statusText = "restic 快照失败: ${result.errorOrNull()?.message}") }
+                        }
+                    }
+                }
+        }
+    }
+}

app/src/main/java/com/example/androidbackupgui/ui/ConfigScreen.kt

@@ -27,7 +27,7 @@ import kotlinx.coroutines.withContext
 @Composable
 fun ConfigScreen(
     viewModel: ConfigViewModel = viewModel(),
-    snackbarHostState: SnackbarHostState = remember { SnackbarHostState() }
+    snackbarHostState: SnackbarHostState = remember { SnackbarHostState() },
 ) {
     val uiState by viewModel.uiState.collectAsStateWithLifecycle()
 
@@ -56,6 +56,7 @@ fun ConfigScreen(
     var resticBackendPass by remember { mutableStateOf(config.resticBackendPass) }
     var resticBackendShare by remember { mutableStateOf(config.resticBackendShare) }
     var resticBackendDomain by remember { mutableStateOf(config.resticBackendDomain) }
+    var streamingEnabled by remember { mutableStateOf(config.useStreaming == 1) }
 
     // Sync local state from ViewModel when config reloads
     LaunchedEffect(config) {
@@ -76,30 +77,35 @@ fun ConfigScreen(
         resticBackendPass = config.resticBackendPass
         resticBackendShare = config.resticBackendShare
         resticBackendDomain = config.resticBackendDomain
+        streamingEnabled = config.useStreaming == 1
     }
 
     // Load user list for backup user selector
     LaunchedEffect(Unit) {
-        val users = withContext(Dispatchers.IO) {
-            AppScanner.enumerateUsers()
-        }
+        val users =
+            withContext(Dispatchers.IO) {
+                AppScanner.enumerateUsers()
+            }
         userList = users
     }
 
     // Observe one-shot events → show Snackbar feedback
     LaunchedEffect(snackbarHostState) {
         viewModel.operationEvents.collect { event ->
-            val msg = when (event) {
-                is OperationEvent.InitCompleted -> "仓库初始化完成"
-                is OperationEvent.InitFailed -> "仓库初始化失败"
-                is OperationEvent.StatsCompleted -> "统计读取完成"
-                is OperationEvent.PruneStarted -> "正在清理快照…"
-                is OperationEvent.PruneCompleted -> "清理完成"
-                is OperationEvent.PruneFailed -> "清理失败"
-                is OperationEvent.ConfigExported -> "配置已导出"
-                is OperationEvent.ConfigExportFailed -> "配置导出失败"
-                else -> null
-            }
+            val msg =
+                when (event) {
+                    is OperationEvent.InitCompleted -> "仓库初始化完成"
+                    is OperationEvent.InitFailed -> "仓库初始化失败"
+                    is OperationEvent.StatsCompleted -> "统计读取完成"
+                    is OperationEvent.PruneStarted -> "正在清理快照…"
+                    is OperationEvent.PruneCompleted -> "清理完成"
+                    is OperationEvent.PruneFailed -> "清理失败"
+                    is OperationEvent.ConfigExported -> "配置已导出"
+                    is OperationEvent.ConfigExportFailed -> "配置导出失败"
+                    is OperationEvent.ConfigImported -> "配置已导入"
+                    is OperationEvent.ConfigImportFailed -> "配置导入失败"
+                    else -> null
+                }
             if (msg != null) {
                 snackbarHostState.showSnackbar(msg)
             }
@@ -109,18 +115,41 @@ fun ConfigScreen(
     val scrollState = rememberScrollState()
 
     // SAF launcher: create a .conf document at a user-chosen location, then export.
-    val exportLauncher = rememberLauncherForActivityResult(
-        contract = ActivityResultContracts.CreateDocument("text/plain")
-    ) { uri ->
-        if (uri != null) viewModel.exportConfig(uri)
-    }
+    val exportLauncher =
+        rememberLauncherForActivityResult(
+            contract = ActivityResultContracts.CreateDocument("text/plain"),
+        ) { uri ->
+            if (uri != null) viewModel.exportConfig(uri)
+        }
+
+    // SAF launcher: pick a .conf file to import.
+    val importLauncher =
+        rememberLauncherForActivityResult(
+            contract = ActivityResultContracts.OpenDocument(),
+        ) { uri ->
+            if (uri != null) viewModel.importConfig(uri)
+        }
+
+    // SAF directory picker for output path
+    val dirPickerLauncher =
+        rememberLauncherForActivityResult(
+            contract = ActivityResultContracts.OpenDocumentTree(),
+        ) { uri ->
+            if (uri != null) {
+                val resolvedPath = resolveSafTreeUri(uri)
+                if (resolvedPath != null) {
+                    outputPath = resolvedPath
+                }
+            }
+        }
 
     Column(
-        modifier = Modifier
-            .fillMaxSize()
-            .verticalScroll(scrollState)
-            .padding(16.dp),
-        verticalArrangement = Arrangement.spacedBy(16.dp)
+        modifier =
+            Modifier
+                .fillMaxSize()
+                .verticalScroll(scrollState)
+                .padding(16.dp),
+        verticalArrangement = Arrangement.spacedBy(16.dp),
     ) {
         // ── Backup settings section ──
         Text("备份设置", style = MaterialTheme.typography.titleMedium)
@@ -146,26 +175,35 @@ fun ConfigScreen(
                     Text("忽略运行中的应用", modifier = Modifier.weight(1f))
                     Switch(checked = ignoreRunning, onCheckedChange = { ignoreRunning = it })
                 }
-                OutlinedTextField(
-                    value = outputPath,
-                    onValueChange = { outputPath = it },
-                    label = { Text("输出目录") },
-                    modifier = Modifier.fillMaxWidth(),
-                    singleLine = true
-                )
+                Row(verticalAlignment = Alignment.CenterVertically, modifier = Modifier.fillMaxWidth()) {
+                    OutlinedTextField(
+                        value = outputPath,
+                        onValueChange = { outputPath = it },
+                        label = { Text("输出目录") },
+                        modifier = Modifier.weight(1f),
+                        singleLine = true,
+                    )
+                    Spacer(Modifier.width(8.dp))
+                    Button(
+                        onClick = { dirPickerLauncher.launch(null) },
+                        modifier = Modifier.height(56.dp),
+                    ) {
+                        Text("选择")
+                    }
+                }
                 OutlinedTextField(
                     value = compressionMethod,
                     onValueChange = { compressionMethod = it },
                     label = { Text("压缩方式 (tar / zstd)") },
                     modifier = Modifier.fillMaxWidth(),
-                    singleLine = true
+                    singleLine = true,
                 )
 
                 // Backup user selector
                 UserSelector(
                     userList = userList,
                     selectedUserId = backupUserId,
-                    onUserSelected = { backupUserId = it }
+                    onUserSelected = { backupUserId = it },
                 )
             }
         }
@@ -183,10 +221,13 @@ fun ConfigScreen(
                 if (resticEnabled) {
                     OutlinedTextField(
                         value = resticRepo,
-                        onValueChange = { resticRepo = it; viewModel.onFormChanged(resticBackend, it, resticBackendUrl) },
+                        onValueChange = {
+                            resticRepo = it
+                            viewModel.onFormChanged(resticBackend, it, resticBackendUrl)
+                        },
                         label = { Text("仓库路径") },
                         modifier = Modifier.fillMaxWidth(),
-                        singleLine = true
+                        singleLine = true,
                     )
                     OutlinedTextField(
                         value = resticPassword,
@@ -194,7 +235,9 @@ fun ConfigScreen(
                         label = { Text("仓库密码") },
                         modifier = Modifier.fillMaxWidth(),
                         singleLine = true,
-                        visualTransformation = androidx.compose.ui.text.input.PasswordVisualTransformation()
+                        visualTransformation =
+                            androidx.compose.ui.text.input
+                                .PasswordVisualTransformation(),
                     )
 
                     // Backend selection radio group
@@ -203,22 +246,22 @@ fun ConfigScreen(
                     Column(modifier = Modifier.selectableGroup()) {
                         backends.forEach { (value, label) ->
                             Row(
-                                modifier = Modifier
-                                    .fillMaxWidth()
-                                    .selectable(
-                                        selected = resticBackend == value,
-                                        onClick = {
-                                            resticBackend = value
-                                            viewModel.onFormChanged(value, resticRepo, resticBackendUrl)
-                                        },
-                                        role = Role.RadioButton
-                                    )
-                                    .padding(vertical = 4.dp),
-                                verticalAlignment = Alignment.CenterVertically
+                                modifier =
+                                    Modifier
+                                        .fillMaxWidth()
+                                        .selectable(
+                                            selected = resticBackend == value,
+                                            onClick = {
+                                                resticBackend = value
+                                                viewModel.onFormChanged(value, resticRepo, resticBackendUrl)
+                                            },
+                                            role = Role.RadioButton,
+                                        ).padding(vertical = 4.dp),
+                                verticalAlignment = Alignment.CenterVertically,
                             ) {
                                 RadioButton(
                                     selected = resticBackend == value,
-                                    onClick = null
+                                    onClick = null,
                                 )
                                 Spacer(Modifier.width(8.dp))
                                 Text(label)
@@ -231,67 +274,89 @@ fun ConfigScreen(
                         Text(
                             text = "实际仓库: ${backendDisplay.computedUrl}",
                             style = MaterialTheme.typography.bodySmall,
-                            color = MaterialTheme.colorScheme.onSurfaceVariant
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
                         )
                     }
                     // Remote-specific fields
                     if (resticBackend != "local") {
-                            OutlinedTextField(
-                                value = resticBackendUrl,
-                                onValueChange = { resticBackendUrl = it; viewModel.onFormChanged(resticBackend, resticRepo, it) },
-                                label = { Text(backendDisplay.urlHint.ifEmpty { "后端地址" }) },
-                                modifier = Modifier.fillMaxWidth(),
-                                singleLine = true
-                            )
-                        }
-                        if (resticBackend == "webdav" || resticBackend == "smb") {
-                            OutlinedTextField(
-                                value = resticBackendUser,
-                                onValueChange = { resticBackendUser = it },
-                                label = { Text("用户名") },
-                                modifier = Modifier.fillMaxWidth(),
-                                singleLine = true
-                            )
-                            OutlinedTextField(
-                                value = resticBackendPass,
-                                onValueChange = { resticBackendPass = it },
-                                label = { Text("密码") },
-                                modifier = Modifier.fillMaxWidth(),
-                                singleLine = true,
-                                visualTransformation = androidx.compose.ui.text.input.PasswordVisualTransformation()
-                            )
-                        }
-                        if (resticBackend == "smb") {
-                            OutlinedTextField(
-                                value = resticBackendShare,
-                                onValueChange = { resticBackendShare = it },
-                                label = { Text("SMB 共享名称") },
-                                modifier = Modifier.fillMaxWidth(),
-                                singleLine = true
-                            )
-                            OutlinedTextField(
-                                value = resticBackendDomain,
-                                onValueChange = { resticBackendDomain = it },
-                                label = { Text("SMB 域 (可选)") },
-                                modifier = Modifier.fillMaxWidth(),
-                                singleLine = true
-                            )
-                        }
+                        OutlinedTextField(
+                            value = resticBackendUrl,
+                            onValueChange = {
+                                resticBackendUrl = it
+                                viewModel.onFormChanged(resticBackend, resticRepo, it)
+                            },
+                            label = { Text(backendDisplay.urlHint.ifEmpty { "后端地址" }) },
+                            modifier = Modifier.fillMaxWidth(),
+                            singleLine = true,
+                        )
+                    }
+                    if (resticBackend == "webdav" || resticBackend == "smb") {
+                        OutlinedTextField(
+                            value = resticBackendUser,
+                            onValueChange = { resticBackendUser = it },
+                            label = { Text("用户名") },
+                            modifier = Modifier.fillMaxWidth(),
+                            singleLine = true,
+                        )
+                        OutlinedTextField(
+                            value = resticBackendPass,
+                            onValueChange = { resticBackendPass = it },
+                            label = { Text("密码") },
+                            modifier = Modifier.fillMaxWidth(),
+                            singleLine = true,
+                            visualTransformation =
+                                androidx.compose.ui.text.input
+                                    .PasswordVisualTransformation(),
+                        )
+                    }
+                    if (resticBackend == "smb") {
+                        OutlinedTextField(
+                            value = resticBackendShare,
+                            onValueChange = { resticBackendShare = it },
+                            label = { Text("SMB 共享名称") },
+                            modifier = Modifier.fillMaxWidth(),
+                            singleLine = true,
+                        )
+                        OutlinedTextField(
+                            value = resticBackendDomain,
+                            onValueChange = { resticBackendDomain = it },
+                            label = { Text("SMB 域 (可选)") },
+                            modifier = Modifier.fillMaxWidth(),
+                            singleLine = true,
+                        )
+                    }
+
+                    // ── Streaming backup toggle ──
+                    Row(
+                        modifier = Modifier.fillMaxWidth(),
+                        verticalAlignment = Alignment.CenterVertically,
+                    ) {
+                        Text(
+                            "流式备份 (FIFO管道 → restic --stdin)",
+                            modifier = Modifier.weight(1f),
+                            style = MaterialTheme.typography.bodyMedium,
+                        )
+                        Switch(
+                            checked = streamingEnabled,
+                            onCheckedChange = { streamingEnabled = it },
+                        )
+                    }
 
                     Spacer(Modifier.height(8.dp))
 
                     // Status & action buttons
                     Card(
-                        colors = CardDefaults.cardColors(
-                            containerColor = MaterialTheme.colorScheme.surfaceVariant
-                        ),
-                        modifier = Modifier.fillMaxWidth()
+                        colors =
+                            CardDefaults.cardColors(
+                                containerColor = MaterialTheme.colorScheme.surfaceVariant,
+                            ),
+                        modifier = Modifier.fillMaxWidth(),
                     ) {
                         Column(modifier = Modifier.padding(12.dp)) {
                             Text(
                                 text = status.message,
                                 style = MaterialTheme.typography.bodyMedium,
-                                color = MaterialTheme.colorScheme.onSurfaceVariant
+                                color = MaterialTheme.colorScheme.onSurfaceVariant,
                             )
 
                             Spacer(Modifier.height(8.dp))
@@ -300,11 +365,20 @@ fun ConfigScreen(
                                 Button(
                                     onClick = {
                                         viewModel.initResticRepo(
-                                            buildResticForm(resticRepo, resticPassword, resticBackend, resticBackendUrl, resticBackendUser, resticBackendPass, resticBackendShare, resticBackendDomain)
+                                            buildResticForm(
+                                                resticRepo,
+                                                resticPassword,
+                                                resticBackend,
+                                                resticBackendUrl,
+                                                resticBackendUser,
+                                                resticBackendPass,
+                                                resticBackendShare,
+                                                resticBackendDomain,
+                                            ),
                                         )
                                     },
                                     enabled = status.initButtonEnabled,
-                                    modifier = Modifier.fillMaxWidth()
+                                    modifier = Modifier.fillMaxWidth(),
                                 ) {
                                     Text("初始化仓库")
                                 }
@@ -314,11 +388,20 @@ fun ConfigScreen(
                                 Button(
                                     onClick = {
                                         viewModel.showResticStats(
-                                            buildResticForm(resticRepo, resticPassword, resticBackend, resticBackendUrl, resticBackendUser, resticBackendPass, resticBackendShare, resticBackendDomain)
+                                            buildResticForm(
+                                                resticRepo,
+                                                resticPassword,
+                                                resticBackend,
+                                                resticBackendUrl,
+                                                resticBackendUser,
+                                                resticBackendPass,
+                                                resticBackendShare,
+                                                resticBackendDomain,
+                                            ),
                                         )
                                     },
                                     enabled = status.statsButtonEnabled,
-                                    modifier = Modifier.fillMaxWidth()
+                                    modifier = Modifier.fillMaxWidth(),
                                 ) {
                                     Text("仓库统计")
                                 }
@@ -328,11 +411,20 @@ fun ConfigScreen(
                                 OutlinedButton(
                                     onClick = {
                                         viewModel.pruneResticSnapshots(
-                                            buildResticForm(resticRepo, resticPassword, resticBackend, resticBackendUrl, resticBackendUser, resticBackendPass, resticBackendShare, resticBackendDomain)
+                                            buildResticForm(
+                                                resticRepo,
+                                                resticPassword,
+                                                resticBackend,
+                                                resticBackendUrl,
+                                                resticBackendUser,
+                                                resticBackendPass,
+                                                resticBackendShare,
+                                                resticBackendDomain,
+                                            ),
                                         )
                                     },
                                     enabled = status.pruneButtonEnabled,
-                                    modifier = Modifier.fillMaxWidth()
+                                    modifier = Modifier.fillMaxWidth(),
                                 ) {
                                     Text("清理旧快照")
                                 }
@@ -342,14 +434,24 @@ fun ConfigScreen(
                                 Button(
                                     onClick = {
                                         viewModel.unlockResticRepo(
-                                            buildResticForm(resticRepo, resticPassword, resticBackend, resticBackendUrl, resticBackendUser, resticBackendPass, resticBackendShare, resticBackendDomain)
+                                            buildResticForm(
+                                                resticRepo,
+                                                resticPassword,
+                                                resticBackend,
+                                                resticBackendUrl,
+                                                resticBackendUser,
+                                                resticBackendPass,
+                                                resticBackendShare,
+                                                resticBackendDomain,
+                                            ),
                                         )
                                     },
                                     enabled = status.unlockButtonEnabled,
                                     modifier = Modifier.fillMaxWidth(),
-                                    colors = ButtonDefaults.buttonColors(
-                                        containerColor = MaterialTheme.colorScheme.tertiary
-                                    )
+                                    colors =
+                                        ButtonDefaults.buttonColors(
+                                            containerColor = MaterialTheme.colorScheme.tertiary,
+                                        ),
                                 ) {
                                     Text("解锁仓库")
                                 }
@@ -384,30 +486,42 @@ fun ConfigScreen(
                         resticBackendPass = resticBackendPass,
                         resticBackendShare = resticBackendShare,
                         resticBackendDomain = resticBackendDomain,
-                    )
+                        useStreaming = if (streamingEnabled) 1 else 0,
+                    ),
                 )
             },
-            modifier = Modifier.fillMaxWidth()
+            modifier = Modifier.fillMaxWidth(),
         ) {
             Icon(Icons.Filled.Save, contentDescription = null)
             Spacer(Modifier.width(8.dp))
             Text("保存配置")
         }
 
-        // ── Export config button ──
-        OutlinedButton(
-            onClick = { exportLauncher.launch("backup_settings.conf") },
-            modifier = Modifier.fillMaxWidth()
+        // ── Import / Export config buttons ──
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalArrangement = Arrangement.spacedBy(8.dp),
         ) {
-            Icon(Icons.Filled.FileUpload, contentDescription = null)
-            Spacer(Modifier.width(8.dp))
-            Text("导出配置")
+            OutlinedButton(
+                onClick = { importLauncher.launch(arrayOf("text/plain", "*/*")) },
+                modifier = Modifier.weight(1f),
+            ) {
+                Text("导入配置")
+            }
+            OutlinedButton(
+                onClick = { exportLauncher.launch("backup_settings.conf") },
+                modifier = Modifier.weight(1f),
+            ) {
+                Icon(Icons.Filled.FileUpload, contentDescription = null)
+                Spacer(Modifier.width(8.dp))
+                Text("导出配置")
+            }
         }
         if (resticEnabled && resticPassword.isNotEmpty()) {
             Text(
                 text = "注意：导出的配置包含明文 Restic 密码，请妥善保管导出的文件。",
                 style = MaterialTheme.typography.bodySmall,
-                color = MaterialTheme.colorScheme.error
+                color = MaterialTheme.colorScheme.error,
             )
         }
 
@@ -422,12 +536,13 @@ fun ConfigScreen(
 private fun UserSelector(
     userList: List<Pair<Int, String>>,
     selectedUserId: Int,
-    onUserSelected: (Int) -> Unit
+    onUserSelected: (Int) -> Unit,
 ) {
     var expanded by remember { mutableStateOf(false) }
-    val selectedName = userList.find { it.first == selectedUserId }?.let {
-        "${it.second} (ID: ${it.first})"
-    } ?: "Owner (ID: 0)"
+    val selectedName =
+        userList.find { it.first == selectedUserId }?.let {
+            "${it.second} (ID: ${it.first})"
+        } ?: "Owner (ID: 0)"
 
     ExposedDropdownMenuBox(expanded = expanded, onExpandedChange = { expanded = it }) {
         OutlinedTextField(
@@ -437,13 +552,16 @@ private fun UserSelector(
             label = { Text("备份用户") },
             trailingIcon = { ExposedDropdownMenuDefaults.TrailingIcon(expanded = expanded) },
             modifier = Modifier.menuAnchor().fillMaxWidth(),
-            singleLine = true
+            singleLine = true,
         )
         ExposedDropdownMenu(expanded = expanded, onDismissRequest = { expanded = false }) {
             userList.forEach { (id, name) ->
                 DropdownMenuItem(
                     text = { Text("$name (ID: $id)") },
-                    onClick = { onUserSelected(id); expanded = false }
+                    onClick = {
+                        onUserSelected(id)
+                        expanded = false
+                    },
                 )
             }
         }
@@ -452,13 +570,46 @@ private fun UserSelector(
 
 /** Build a [ResticForm] from current input values (matches ConfigFragment's readResticForm). */
 private fun buildResticForm(
-    repo: String, password: String,
-    backend: String, backendUrl: String,
-    backendUser: String, backendPass: String,
-    backendShare: String, backendDomain: String
+    repo: String,
+    password: String,
+    backend: String,
+    backendUrl: String,
+    backendUser: String,
+    backendPass: String,
+    backendShare: String,
+    backendDomain: String,
 ) = ResticForm(
-    repo = repo, password = password,
-    backend = backend, backendUrl = backendUrl,
-    backendUser = backendUser, backendPass = backendPass,
-    backendShare = backendShare, backendDomain = backendDomain
+    repo = repo,
+    password = password,
+    backend = backend,
+    backendUrl = backendUrl,
+    backendUser = backendUser,
+    backendPass = backendPass,
+    backendShare = backendShare,
+    backendDomain = backendDomain,
 )
+
+/**
+ * 将 SAF OpenDocumentTree 的 content:// URI 转换为可用的文件系统路径。
+ * SAF URI 示例: content://com.android.externalstorage.documents/tree/primary%3ADownload%2FBackup
+ * 返回: /storage/emulated/0/Download/Backup
+ */
+private fun resolveSafTreeUri(uri: android.net.Uri): String? {
+    // SAF tree URI 格式:
+    //   content://com.android.externalstorage.documents/tree/primary%3ADownload%2FBackup
+    // lastPathSegment = primary%3ADownload%2FBackup 或 XXXX-XXXX%3Apath
+    val docId = uri.lastPathSegment?.let { java.net.URLDecoder.decode(it, "UTF-8") } ?: return null
+
+    // docId 格式: primary:path/to/dir 或 XXXX-XXXX:path/to/dir
+    val colonIdx = docId.indexOf(':')
+    if (colonIdx < 0) return null
+
+    val storageId = docId.substring(0, colonIdx)
+    val relPath = docId.substring(colonIdx + 1).trim('/')
+
+    return if (storageId.equals("primary", ignoreCase = true)) {
+        "/storage/emulated/0/$relPath"
+    } else {
+        "/storage/$storageId/$relPath"
+    }
+}

app/src/main/java/com/example/androidbackupgui/ui/ConfigViewModel.kt

@@ -1,24 +1,25 @@
 package com.example.androidbackupgui.ui
-
 import android.app.Application
 import android.util.Log
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
 import com.example.androidbackupgui.backup.BackupConfig
-import com.example.androidbackupgui.backup.formatSize
+import com.example.androidbackupgui.backup.PasswordManager
 import com.example.androidbackupgui.backup.ResticBinary
 import com.example.androidbackupgui.backup.ResticWrapper
+import com.example.androidbackupgui.backup.defaultResticWrapper
+import com.example.androidbackupgui.backup.formatSize
 import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.StateFlow
-import kotlinx.coroutines.flow.asStateFlow
-import kotlinx.coroutines.flow.MutableSharedFlow
-import kotlinx.coroutines.flow.SharedFlow
-import kotlinx.coroutines.flow.asSharedFlow
-import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.Job
-import kotlinx.coroutines.launch
 import kotlinx.coroutines.cancelAndJoin
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharedFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asSharedFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import java.io.File
 import java.util.concurrent.atomic.AtomicBoolean
@@ -27,7 +28,7 @@ import java.util.concurrent.atomic.AtomicBoolean
 data class ConfigUiState(
     val config: BackupConfig = BackupConfig(),
     val backendDisplay: BackendDisplay = BackendDisplay(),
-    val resticStatus: ResticStatus = ResticStatus()
+    val resticStatus: ResticStatus = ResticStatus(),
 )
 
 data class BackendDisplay(
@@ -35,7 +36,7 @@ data class BackendDisplay(
     val needsAuth: Boolean = false,
     val isSmb: Boolean = false,
     val computedUrl: String = "",
-    val urlHint: String = ""
+    val urlHint: String = "",
 )
 
 data class ResticStatus(
@@ -48,15 +49,19 @@ data class ResticStatus(
     val pruneButtonVisible: Boolean = false,
     val pruneButtonEnabled: Boolean = true,
     val unlockButtonVisible: Boolean = false,
-    val unlockButtonEnabled: Boolean = true
+    val unlockButtonEnabled: Boolean = true,
 )
 
 /** Restic credential/form snapshot passed from Fragment on every user interaction. */
 data class ResticForm(
-    val repo: String, val password: String,
-    val backend: String, val backendUrl: String,
-    val backendUser: String, val backendPass: String,
-    val backendShare: String, val backendDomain: String
+    val repo: String,
+    val password: String,
+    val backend: String,
+    val backendUrl: String,
+    val backendUser: String,
+    val backendPass: String,
+    val backendShare: String,
+    val backendDomain: String,
 )
 
 /**
@@ -65,40 +70,61 @@ data class ResticForm(
  */
 sealed interface OperationEvent {
     data object InitStarted : OperationEvent
+
     data object InitCompleted : OperationEvent
+
     data object InitFailed : OperationEvent
+
     data object StatsStarted : OperationEvent
+
     data object StatsCompleted : OperationEvent
+
     data object PruneStarted : OperationEvent
+
     data object PruneFailed : OperationEvent
+
     data object PruneCompleted : OperationEvent
+
     data object ConfigExported : OperationEvent
+
     data object ConfigExportFailed : OperationEvent
+
+    data object ConfigImported : OperationEvent
+
+    data object ConfigImportFailed : OperationEvent
 }
 
-class ConfigViewModel(application: Application) : AndroidViewModel(application) {
-
+class ConfigViewModel(
+    application: Application,
+) : AndroidViewModel(application) {
     companion object {
         private const val TAG = "ConfigViewModel"
         private const val CONFIG_FILE_NAME = "backup_settings.conf"
 
-        fun deriveBackendDisplay(backend: String, repo: String, backendUrl: String): BackendDisplay {
+        fun deriveBackendDisplay(
+            backend: String,
+            repo: String,
+            backendUrl: String,
+        ): BackendDisplay {
             val isRemote = backend != "local"
             val needsAuth = backend == "webdav" || backend == "smb"
             val isSmb = backend == "smb"
-            val urlHint = when (backend) {
-                "webdav" -> "WebDAV 地址 (https://host:port/path)"
-                "smb" -> "SMB 主机地址 (host 或 host:port)"
-                "rest-server" -> "rest-server 地址 (http://host:port)"
-                else -> ""
-            }
-            val computedUrl = ResticWrapper.buildRepoUrl(backend, repo, backendUrl)
+            val urlHint =
+                when (backend) {
+                    "webdav" -> "WebDAV 地址 (https://host:port/path)"
+                    "smb" -> "SMB 主机地址 (host 或 host:port)"
+                    "rest-server" -> "rest-server 地址 (http://host:port)"
+                    else -> ""
+                }
+            val computedUrl = defaultResticWrapper.buildRepoUrl(backend, repo, backendUrl)
             return BackendDisplay(
-                isRemote = isRemote, needsAuth = needsAuth, isSmb = isSmb,
-                computedUrl = computedUrl, urlHint = urlHint
+                isRemote = isRemote,
+                needsAuth = needsAuth,
+                isSmb = isSmb,
+                computedUrl = computedUrl,
+                urlHint = urlHint,
             )
         }
-
     }
 
     private val configFile: File by lazy {
@@ -132,18 +158,40 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
         refreshResticStatus(readResticForm())
     }
 
-    /** Build a [ResticForm] snapshot from the current state's config values. */
-    private fun readResticForm() = _uiState.value.config.let { c ->
-        ResticForm(
-            repo = c.resticRepo, password = c.resticPassword,
-            backend = c.resticBackend, backendUrl = c.resticBackendUrl,
-            backendUser = c.resticBackendUser, backendPass = c.resticBackendPass,
-            backendShare = c.resticBackendShare, backendDomain = c.resticBackendDomain
-        )
-    }
+    /**
+     * Build a [ResticForm] snapshot from the current state's config values.
+     * 密码从 PasswordManager（加密存储）获取，不从配置文件读取。
+     */
+    private fun readResticForm() =
+        _uiState.value.config.let { c ->
+            // 从加密存储获取密码，如尚未设置则尝试从旧配置迁移
+            val password = PasswordManager.getResticPassword() ?: c.resticPassword.takeIf { it.isNotEmpty() }
+            val backendPass = PasswordManager.getBackendPass() ?: c.resticBackendPass.takeIf { it.isNotEmpty() }
+            // 如果发现旧配置中有密码但 PasswordManager 还没有，迁移过去
+            if (password != null && !PasswordManager.hasResticPassword() && password != "stored-in-keystore") {
+                PasswordManager.setResticPassword(password)
+            }
+            if (backendPass != null && backendPass != "stored-in-keystore" && PasswordManager.getBackendPass() == null) {
+                PasswordManager.setBackendPass(backendPass)
+            }
+            ResticForm(
+                repo = c.resticRepo,
+                password = password ?: "",
+                backend = c.resticBackend,
+                backendUrl = c.resticBackendUrl,
+                backendUser = c.resticBackendUser,
+                backendPass = backendPass ?: "",
+                backendShare = c.resticBackendShare,
+                backendDomain = c.resticBackendDomain,
+            )
+        }
 
     /** Update derived display state when backend/repo/url form fields change. */
-    fun onFormChanged(backend: String, repo: String, backendUrl: String) {
+    fun onFormChanged(
+        backend: String,
+        repo: String,
+        backendUrl: String,
+    ) {
         val bd = deriveBackendDisplay(backend, repo, backendUrl)
         _uiState.update { it.copy(backendDisplay = bd) }
     }
@@ -151,21 +199,34 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
     /**
      * Save config to file on IO and update status message.
      * The caller passes the current form values as a [BackupConfig] copy.
+     * 密码单独通过 [PasswordManager] 安全存储，不入配置文件。
      */
-    fun save(formConfig: BackupConfig) {
+    fun save(
+        formConfig: BackupConfig,
+        resticPassword: String? = null,
+        backendPass: String? = null,
+    ) {
         viewModelScope.launch {
+            // 保存密码到加密存储
+            if (resticPassword != null && resticPassword.isNotEmpty()) {
+                PasswordManager.setResticPassword(resticPassword)
+            }
+            if (backendPass != null && backendPass.isNotEmpty()) {
+                PasswordManager.setBackendPass(backendPass)
+            }
             withContext(Dispatchers.IO) {
                 BackupConfig.toFile(formConfig, configFile)
             }
             _uiState.update {
                 it.copy(
                     config = formConfig,
-                    backendDisplay = deriveBackendDisplay(
-                        formConfig.resticBackend,
-                        formConfig.resticRepo,
-                        formConfig.resticBackendUrl
-                    ),
-                    resticStatus = it.resticStatus.copy(message = "配置已保存到 $configFile")
+                    backendDisplay =
+                        deriveBackendDisplay(
+                            formConfig.resticBackend,
+                            formConfig.resticRepo,
+                            formConfig.resticBackendUrl,
+                        ),
+                    resticStatus = it.resticStatus.copy(message = "配置已保存到 $configFile"),
                 )
             }
             refreshResticStatus(readResticForm())
@@ -179,31 +240,42 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
      */
     fun exportConfig(uri: android.net.Uri) {
         viewModelScope.launch {
-            val ok = withContext(Dispatchers.IO) {
-                try {
-                    // Ensure the latest saved config exists; serialize current UI config
-                    // if the file isn't there yet.
-                    val content = if (configFile.exists()) {
-                        configFile.readText()
-                    } else {
-                        val tmp = File.createTempFile("cfg", ".conf", getApplication<Application>().cacheDir)
-                        BackupConfig.toFile(_uiState.value.config, tmp)
-                        tmp.readText().also { tmp.delete() }
+            val ok =
+                withContext(Dispatchers.IO) {
+                    try {
+                        // Ensure the latest saved config exists; serialize current UI config
+                        // if the file isn't there yet.
+                        val content =
+                            if (configFile.exists()) {
+                                configFile.readText()
+                            } else {
+                                val tmp = File.createTempFile("cfg", ".conf", getApplication<Application>().cacheDir)
+                                BackupConfig.toFile(_uiState.value.config, tmp)
+                                tmp.readText().also { tmp.delete() }
+                            }
+                        getApplication<Application>()
+                            .contentResolver
+                            .openOutputStream(uri)
+                            ?.use { out ->
+                                out.write(content.toByteArray())
+                                out.flush()
+                            } ?: return@withContext false
+                        true
+                    } catch (e: Exception) {
+                        Log.e(TAG, "exportConfig failed", e)
+                        false
                     }
-                    getApplication<Application>().contentResolver
-                        .openOutputStream(uri)?.use { out ->
-                            out.write(content.toByteArray())
-                            out.flush()
-                        } ?: return@withContext false
-                    true
-                } catch (e: Exception) {
-                    Log.e(TAG, "exportConfig failed", e)
-                    false
                 }
-            }
             if (ok) {
                 _operationEvents.emit(OperationEvent.ConfigExported)
-                _uiState.update { it.copy(resticStatus = it.resticStatus.copy(message = "配置已导出")) }
+                _uiState.update {
+                    it.copy(
+                        resticStatus =
+                            it.resticStatus.copy(
+                                message = "配置已导出（密码未包含，需在目标设备上通过应用重新输入）",
+                            ),
+                    )
+                }
             } else {
                 _operationEvents.emit(OperationEvent.ConfigExportFailed)
                 _uiState.update { it.copy(resticStatus = it.resticStatus.copy(message = "配置导出失败")) }
@@ -211,13 +283,78 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
         }
     }
 
+    /**
+     * Import config from a user-selected [Uri] (SAF).
+     * Reads the content, writes to configFile, and reloads UI state.
+     */
+    fun importConfig(uri: android.net.Uri) {
+        viewModelScope.launch {
+            val ok =
+                withContext(Dispatchers.IO) {
+                    try {
+                        val content =
+                            getApplication<Application>()
+                                .contentResolver
+                                .openInputStream(uri)
+                                ?.use { input -> input.reader().readText() }
+                                ?: return@withContext false
+                        configFile.writeText(content)
+                        val parsed = BackupConfig.fromFile(configFile)
+                        // 导入的配置中密码是 "stored-in-keystore" 占位符，
+                        // 需要从 PasswordManager 恢复真实密码，避免被覆盖
+                        val realResticPw = PasswordManager.getResticPassword()
+                        val realBackendPw = PasswordManager.getBackendPass()
+                        val restoredConfig =
+                            parsed.copy(
+                                resticPassword = realResticPw ?: parsed.resticPassword,
+                                resticBackendPass = realBackendPw ?: parsed.resticBackendPass,
+                            )
+                        _uiState.update { it.copy(config = restoredConfig) }
+                        Log.i(TAG, "importConfig: loaded config from SAF")
+                        true
+                    } catch (e: Exception) {
+                        Log.e(TAG, "importConfig failed", e)
+                        false
+                    }
+                }
+            if (ok) {
+                _operationEvents.emit(OperationEvent.ConfigImported)
+                _uiState.update {
+                    it.copy(
+                        resticStatus =
+                            it.resticStatus.copy(
+                                message = "配置已导入，请检查各项设置并保存",
+                            ),
+                    )
+                }
+                // Reload UI state from imported config，保留已有的密码
+                val s = _uiState.value
+                refreshResticStatus(
+                    ResticForm(
+                        repo = s.config.resticRepo,
+                        password = PasswordManager.getResticPassword() ?: "",
+                        backend = s.config.resticBackend,
+                        backendUrl = s.config.resticBackendUrl,
+                        backendUser = s.config.resticBackendUser,
+                        backendPass = PasswordManager.getBackendPass() ?: "",
+                        backendShare = s.config.resticBackendShare,
+                        backendDomain = s.config.resticBackendDomain,
+                    ),
+                )
+            } else {
+                _operationEvents.emit(OperationEvent.ConfigImportFailed)
+                _uiState.update { it.copy(resticStatus = it.resticStatus.copy(message = "配置导入失败")) }
+            }
+        }
+    }
+
     /** Prepare ResticWrapper (binary, temp dir, domain) from application context. */
     private fun prepareRestic(): Boolean {
         val ctx = getApplication<Application>()
         val binaryPath = ResticBinary.prepare(ctx)
         if (binaryPath == null) return false
-        ResticWrapper.binaryPath = binaryPath
-        ResticWrapper.cacheDir = ctx.cacheDir.absolutePath
+        defaultResticWrapper.binaryPath = binaryPath
+        defaultResticWrapper.cacheDir = ctx.cacheDir.absolutePath
         return true
     }
 
@@ -231,12 +368,17 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
         Log.i(TAG, "initResticRepo called: repo=${form.repo} backend=${form.backend}")
 
         if (!prepareRestic()) {
-            _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-                message = "restic 二进制未就绪，请确保已安装 restic 于 Termux 或 APK 内置版本可用"
-            ))}
+            _uiState.update {
+                it.copy(
+                    resticStatus =
+                        it.resticStatus.copy(
+                            message = "restic 二进制未就绪，请确保已安装 restic 于 Termux 或 APK 内置版本可用",
+                        ),
+                )
+            }
             return
         }
-        ResticWrapper.backendDomain = form.backendDomain
+        defaultResticWrapper.backendDomain = form.backendDomain
         Log.i(TAG, "initResticRepo: repo=${form.repo} backend=${form.backend} url=${form.backendUrl}")
 
         if (form.repo.isEmpty() || form.password.isEmpty()) {
@@ -244,30 +386,51 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
             return
         }
 
-        _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-            message = "正在初始化 restic 仓库…", initButtonEnabled = false
-        ))}
+        _uiState.update {
+            it.copy(
+                resticStatus =
+                    it.resticStatus.copy(
+                        message = "正在初始化 restic 仓库…",
+                        initButtonEnabled = false,
+                    ),
+            )
+        }
 
         viewModelScope.launch {
             try {
                 _operationEvents.emit(OperationEvent.InitStarted)
-                val result = ResticWrapper.init(form.repo, form.password,
-                    backend = form.backend, backendUrl = form.backendUrl,
-                    backendUser = form.backendUser, backendPass = form.backendPass,
-                    backendShare = form.backendShare,
-                )
+                val result =
+                    defaultResticWrapper.init(
+                        form.repo,
+                        form.password,
+                        backend = form.backend,
+                        backendUrl = form.backendUrl,
+                        backendUser = form.backendUser,
+                        backendPass = form.backendPass,
+                        backendShare = form.backendShare,
+                    )
                 if (result.isSuccess) {
                     _operationEvents.emit(OperationEvent.InitCompleted)
-                    _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-                        message = "仓库初始化成功: ${form.repo}"
-                    ))}
+                    _uiState.update {
+                        it.copy(
+                            resticStatus =
+                                it.resticStatus.copy(
+                                    message = "仓库初始化成功: ${form.repo}",
+                                ),
+                        )
+                    }
                     refreshResticStatus(form)
                 } else {
                     _operationEvents.emit(OperationEvent.InitFailed)
                     Log.e(TAG, "initResticRepo failed: ${result.exceptionOrNull()?.message}")
-                    _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-                        message = "初始化失败: ${result.exceptionOrNull()?.message}"
-                    ))}
+                    _uiState.update {
+                        it.copy(
+                            resticStatus =
+                                it.resticStatus.copy(
+                                    message = "初始化失败: ${result.exceptionOrNull()?.message}",
+                                ),
+                        )
+                    }
                     refreshResticStatus(form)
                 }
             } finally {
@@ -278,131 +441,229 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
 
     fun refreshResticStatus(form: ResticForm) {
         if (form.repo.isBlank()) {
-            _uiState.update { it.copy(resticStatus = ResticStatus(
-                message = "请填写仓库路径和密码后初始化",
-                initButtonVisible = true, statsButtonVisible = false, pruneButtonVisible = false
-            ))}
+            _uiState.update {
+                it.copy(
+                    resticStatus =
+                        ResticStatus(
+                            message = "请填写仓库路径和密码后初始化",
+                            initButtonVisible = true,
+                            statsButtonVisible = false,
+                            pruneButtonVisible = false,
+                        ),
+                )
+            }
             return
         }
 
         if (!prepareRestic()) {
-            _uiState.update { it.copy(resticStatus = ResticStatus(
-                message = "restic 二进制未就绪",
-                initButtonVisible = true, statsButtonVisible = false, pruneButtonVisible = false
-            ))}
+            _uiState.update {
+                it.copy(
+                    resticStatus =
+                        ResticStatus(
+                            message = "restic 二进制未就绪",
+                            initButtonVisible = true,
+                            statsButtonVisible = false,
+                            pruneButtonVisible = false,
+                        ),
+                )
+            }
             return
         }
-        ResticWrapper.backendDomain = form.backendDomain
+        defaultResticWrapper.backendDomain = form.backendDomain
 
         _uiState.update { it.copy(resticStatus = it.resticStatus.copy(message = "正在检测仓库状态…")) }
 
         // Cancel any stale status check so a slow old coroutine doesn't overwrite new results
         refreshJob?.cancel()
-        refreshJob = viewModelScope.launch {
-            val snapshotsResult = ResticWrapper.listSnapshots(form.repo, form.password,
-                backend = form.backend, backendUrl = form.backendUrl,
-                backendUser = form.backendUser, backendPass = form.backendPass,
-                backendShare = form.backendShare,
-            )
-            if (snapshotsResult.isSuccess) {
-                val snapshots = snapshotsResult.getOrDefault(emptyList())
-                _uiState.update { it.copy(resticStatus = ResticStatus(
-                    message = "仓库就绪，${snapshots.size} 个快照",
-                    snapshotCount = snapshots.size,
-                    initButtonVisible = false, statsButtonVisible = true, pruneButtonVisible = true,
-                    unlockButtonVisible = true
-                ))}
-            } else {
-                val errMsg = snapshotsResult.errorOrNull()?.message ?: ""
-                val hasLock = errMsg.contains("lock", ignoreCase = true) || errMsg.contains("already locked", ignoreCase = true)
-
-                if (hasLock) {
-                    _uiState.update { it.copy(resticStatus = ResticStatus(
-                        message = "仓库被锁定，请先解锁",
-                        initButtonVisible = false, statsButtonVisible = false, pruneButtonVisible = false,
-                        unlockButtonVisible = true
-                    ))}
-                } else {
-                    // snapshots 失败时自动尝试 init（处理已初始化的旧仓库）
-                    val initResult = ResticWrapper.init(form.repo, form.password,
-                        backend = form.backend, backendUrl = form.backendUrl,
-                        backendUser = form.backendUser, backendPass = form.backendPass,
+        refreshJob =
+            viewModelScope.launch {
+                val snapshotsResult =
+                    defaultResticWrapper.listSnapshots(
+                        form.repo,
+                        form.password,
+                        backend = form.backend,
+                        backendUrl = form.backendUrl,
+                        backendUser = form.backendUser,
+                        backendPass = form.backendPass,
                         backendShare = form.backendShare,
                     )
-                    if (initResult.isSuccess) {
-                        val snaps = ResticWrapper.listSnapshots(form.repo, form.password,
-                            backend = form.backend, backendUrl = form.backendUrl,
-                            backendUser = form.backendUser, backendPass = form.backendPass,
-                            backendShare = form.backendShare,
-                        ).getOrDefault(emptyList())
-                        _uiState.update { it.copy(resticStatus = ResticStatus(
-                            message = "仓库就绪，${snaps.size} 个快照",
-                            snapshotCount = snaps.size,
-                            initButtonVisible = false, statsButtonVisible = true, pruneButtonVisible = true,
-                            unlockButtonVisible = true
-                        ))}
+                if (snapshotsResult.isSuccess) {
+                    val snapshots = snapshotsResult.getOrDefault(emptyList())
+                    _uiState.update {
+                        it.copy(
+                            resticStatus =
+                                ResticStatus(
+                                    message = "仓库就绪，${snapshots.size} 个快照",
+                                    snapshotCount = snapshots.size,
+                                    initButtonVisible = false,
+                                    statsButtonVisible = true,
+                                    pruneButtonVisible = true,
+                                    unlockButtonVisible = true,
+                                ),
+                        )
+                    }
+                } else {
+                    val errMsg = snapshotsResult.errorOrNull()?.message ?: ""
+                    val hasLock = errMsg.contains("lock", ignoreCase = true) || errMsg.contains("already locked", ignoreCase = true)
+
+                    if (hasLock) {
+                        _uiState.update {
+                            it.copy(
+                                resticStatus =
+                                    ResticStatus(
+                                        message = "仓库被锁定，请先解锁",
+                                        initButtonVisible = false,
+                                        statsButtonVisible = false,
+                                        pruneButtonVisible = false,
+                                        unlockButtonVisible = true,
+                                    ),
+                            )
+                        }
                     } else {
-                        _uiState.update { it.copy(resticStatus = ResticStatus(
-                            message = "仓库未初始化或认证失败",
-                            initButtonVisible = true, statsButtonVisible = false, pruneButtonVisible = false,
-                            unlockButtonVisible = false
-                        ))}
+                        // snapshots 失败时自动尝试 init（处理已初始化的旧仓库）
+                        val initResult =
+                            defaultResticWrapper.init(
+                                form.repo,
+                                form.password,
+                                backend = form.backend,
+                                backendUrl = form.backendUrl,
+                                backendUser = form.backendUser,
+                                backendPass = form.backendPass,
+                                backendShare = form.backendShare,
+                            )
+                        if (initResult.isSuccess) {
+                            val snaps =
+                                defaultResticWrapper
+                                    .listSnapshots(
+                                        form.repo,
+                                        form.password,
+                                        backend = form.backend,
+                                        backendUrl = form.backendUrl,
+                                        backendUser = form.backendUser,
+                                        backendPass = form.backendPass,
+                                        backendShare = form.backendShare,
+                                    ).getOrDefault(emptyList())
+                            _uiState.update {
+                                it.copy(
+                                    resticStatus =
+                                        ResticStatus(
+                                            message = "仓库就绪，${snaps.size} 个快照",
+                                            snapshotCount = snaps.size,
+                                            initButtonVisible = false,
+                                            statsButtonVisible = true,
+                                            pruneButtonVisible = true,
+                                            unlockButtonVisible = true,
+                                        ),
+                                )
+                            }
+                        } else {
+                            _uiState.update {
+                                it.copy(
+                                    resticStatus =
+                                        ResticStatus(
+                                            message = "仓库未初始化或认证失败",
+                                            initButtonVisible = true,
+                                            statsButtonVisible = false,
+                                            pruneButtonVisible = false,
+                                            unlockButtonVisible = false,
+                                        ),
+                                )
+                            }
+                        }
                     }
                 }
             }
-        }
     }
+
     fun unlockResticRepo(form: ResticForm) {
-        _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-            message = "正在解锁仓库…", unlockButtonEnabled = false
-        ))}
-        viewModelScope.launch {
-            ResticWrapper.backendDomain = form.backendDomain
-            val result = ResticWrapper.unlock(form.repo, form.password,
-                backend = form.backend, backendUrl = form.backendUrl,
-                backendUser = form.backendUser, backendPass = form.backendPass,
-                backendShare = form.backendShare,
+        _uiState.update {
+            it.copy(
+                resticStatus =
+                    it.resticStatus.copy(
+                        message = "正在解锁仓库…",
+                        unlockButtonEnabled = false,
+                    ),
             )
-            _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-                message = if (result.isSuccess) "解锁完成" else "解锁失败: ${result.errorOrNull()?.message}",
-                unlockButtonEnabled = true
-            ))}
+        }
+        viewModelScope.launch {
+            defaultResticWrapper.backendDomain = form.backendDomain
+            val result =
+                defaultResticWrapper.unlock(
+                    form.repo,
+                    form.password,
+                    backend = form.backend,
+                    backendUrl = form.backendUrl,
+                    backendUser = form.backendUser,
+                    backendPass = form.backendPass,
+                    backendShare = form.backendShare,
+                )
+            _uiState.update {
+                it.copy(
+                    resticStatus =
+                        it.resticStatus.copy(
+                            message = if (result.isSuccess) "解锁完成" else "解锁失败: ${result.errorOrNull()?.message}",
+                            unlockButtonEnabled = true,
+                        ),
+                )
+            }
             refreshResticStatus(form)
         }
     }
 
     fun showResticStats(form: ResticForm) {
-        _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-            message = "正在读取统计…", statsButtonEnabled = false
-        ))}
+        _uiState.update {
+            it.copy(
+                resticStatus =
+                    it.resticStatus.copy(
+                        message = "正在读取统计…",
+                        statsButtonEnabled = false,
+                    ),
+            )
+        }
 
         viewModelScope.launch {
             try {
                 _operationEvents.emit(OperationEvent.StatsStarted)
-                val statsResult = ResticWrapper.stats(form.repo, form.password,
-                    backend = form.backend, backendUrl = form.backendUrl,
-                    backendUser = form.backendUser, backendPass = form.backendPass,
-                    backendShare = form.backendShare,
-                )
-                val snapshotsResult = ResticWrapper.listSnapshots(form.repo, form.password,
-                    backend = form.backend, backendUrl = form.backendUrl,
-                    backendUser = form.backendUser, backendPass = form.backendPass,
-                    backendShare = form.backendShare,
-                )
+                val statsResult =
+                    defaultResticWrapper.stats(
+                        form.repo,
+                        form.password,
+                        backend = form.backend,
+                        backendUrl = form.backendUrl,
+                        backendUser = form.backendUser,
+                        backendPass = form.backendPass,
+                        backendShare = form.backendShare,
+                    )
+                val snapshotsResult =
+                    defaultResticWrapper.listSnapshots(
+                        form.repo,
+                        form.password,
+                        backend = form.backend,
+                        backendUrl = form.backendUrl,
+                        backendUser = form.backendUser,
+                        backendPass = form.backendPass,
+                        backendShare = form.backendShare,
+                    )
 
                 val snapshotCount = snapshotsResult.getOrDefault(emptyList()).size
-                _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-                    message = buildString {
-                        appendLine("快照数: $snapshotCount")
-                        if (statsResult.isSuccess) {
-                            appendLine(statsResult.getOrDefault(""))
-                        } else {
-                            appendLine("统计读取失败: ${statsResult.errorOrNull()?.message}")
-                        }
-                    },
-                    snapshotCount = snapshotCount,
-                    statsButtonEnabled = true
-                ))}
+                _uiState.update {
+                    it.copy(
+                        resticStatus =
+                            it.resticStatus.copy(
+                                message =
+                                    buildString {
+                                        appendLine("快照数: $snapshotCount")
+                                        if (statsResult.isSuccess) {
+                                            appendLine(statsResult.getOrDefault(""))
+                                        } else {
+                                            appendLine("统计读取失败: ${statsResult.errorOrNull()?.message}")
+                                        }
+                                    },
+                                snapshotCount = snapshotCount,
+                                statsButtonEnabled = true,
+                            ),
+                    )
+                }
                 _operationEvents.emit(OperationEvent.StatsCompleted)
             } finally {
                 _uiState.update { it.copy(resticStatus = it.resticStatus.copy(statsButtonEnabled = true)) }
@@ -411,52 +672,85 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
     }
 
     fun pruneResticSnapshots(form: ResticForm) {
-        _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-            message = "正在清理旧快照 (保留 7 天 / 4 周 / 3 月)…",
-            pruneButtonEnabled = false
-        ))}
+        _uiState.update {
+            it.copy(
+                resticStatus =
+                    it.resticStatus.copy(
+                        message = "正在清理旧快照 (保留 7 天 / 4 周 / 3 月)…",
+                        pruneButtonEnabled = false,
+                    ),
+            )
+        }
 
         viewModelScope.launch {
             try {
                 _operationEvents.emit(OperationEvent.PruneStarted)
 
                 // Remove stale locks before forget/prune
-                ResticWrapper.backendDomain = form.backendDomain
-                ResticWrapper.unlock(form.repo, form.password,
-                    backend = form.backend, backendUrl = form.backendUrl,
-                    backendUser = form.backendUser, backendPass = form.backendPass,
+                defaultResticWrapper.backendDomain = form.backendDomain
+                defaultResticWrapper.unlock(
+                    form.repo,
+                    form.password,
+                    backend = form.backend,
+                    backendUrl = form.backendUrl,
+                    backendUser = form.backendUser,
+                    backendPass = form.backendPass,
                     backendShare = form.backendShare,
                 )
 
-                val forgetResult = ResticWrapper.forget(form.repo, form.password,
-                    keepDaily = 7, keepWeekly = 4, keepMonthly = 3,
-                    backend = form.backend, backendUrl = form.backendUrl,
-                    backendUser = form.backendUser, backendPass = form.backendPass,
-                    backendShare = form.backendShare,
-                )
+                val forgetResult =
+                    defaultResticWrapper.forget(
+                        form.repo,
+                        form.password,
+                        keepDaily = 7,
+                        keepWeekly = 4,
+                        keepMonthly = 3,
+                        backend = form.backend,
+                        backendUrl = form.backendUrl,
+                        backendUser = form.backendUser,
+                        backendPass = form.backendPass,
+                        backendShare = form.backendShare,
+                    )
                 if (forgetResult.isFailure) {
                     _operationEvents.emit(OperationEvent.PruneFailed)
-                    _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-                        message = "forget 失败: ${forgetResult.exceptionOrNull()?.message}",
-                        pruneButtonEnabled = true
-                    ))}
+                    _uiState.update {
+                        it.copy(
+                            resticStatus =
+                                it.resticStatus.copy(
+                                    message = "forget 失败: ${forgetResult.exceptionOrNull()?.message}",
+                                    pruneButtonEnabled = true,
+                                ),
+                        )
+                    }
                     return@launch
                 }
 
                 _uiState.update { it.copy(resticStatus = it.resticStatus.copy(message = "正在回收空间…")) }
 
-                val pruneResult = ResticWrapper.prune(form.repo, form.password,
-                    backend = form.backend, backendUrl = form.backendUrl,
-                    backendUser = form.backendUser, backendPass = form.backendPass,
-                    backendShare = form.backendShare,
-                )
-                _uiState.update { it.copy(resticStatus = it.resticStatus.copy(
-                    message = if (pruneResult.isSuccess)
-                        "清理完成！\n${pruneResult.getOrDefault("")}"
-                    else
-                        "prune 失败: ${pruneResult.exceptionOrNull()?.message}",
-                    pruneButtonEnabled = true
-                ))}
+                val pruneResult =
+                    defaultResticWrapper.prune(
+                        form.repo,
+                        form.password,
+                        backend = form.backend,
+                        backendUrl = form.backendUrl,
+                        backendUser = form.backendUser,
+                        backendPass = form.backendPass,
+                        backendShare = form.backendShare,
+                    )
+                _uiState.update {
+                    it.copy(
+                        resticStatus =
+                            it.resticStatus.copy(
+                                message =
+                                    if (pruneResult.isSuccess) {
+                                        "清理完成！建议执行完整性检查 (check --read-data-subset=5%)"
+                                    } else {
+                                        "prune 失败: ${pruneResult.exceptionOrNull()?.message}"
+                                    },
+                                pruneButtonEnabled = true,
+                            ),
+                    )
+                }
                 if (pruneResult.isSuccess) {
                     _operationEvents.emit(OperationEvent.PruneCompleted)
                 } else {
@@ -467,6 +761,4 @@ class ConfigViewModel(application: Application) : AndroidViewModel(application)
             }
         }
     }
-
-
 }

app/src/main/java/com/example/androidbackupgui/ui/LogScreen.kt

@@ -0,0 +1,202 @@
+package com.example.androidbackupgui.ui
+
+import android.content.Context
+import android.net.Uri
+import android.util.Log
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.compose.foundation.layout.*
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material.icons.filled.FileDownload
+import androidx.compose.material.icons.filled.Refresh
+import androidx.compose.material3.*
+import androidx.compose.runtime.*
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.unit.dp
+import com.example.androidbackupgui.backup.LogUtil
+import java.io.File
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun LogScreen() {
+    val context = LocalContext.current
+    var logFiles by remember { mutableStateOf(listOf<File>()) }
+    var selectedFile by remember { mutableStateOf<File?>(null) }
+    var logContent by remember { mutableStateOf<List<String>>(emptyList()) }
+    val scope = rememberCoroutineScope()
+
+    // Refresh log list
+    fun refresh() {
+        logFiles = LogUtil.getLogFiles()
+        if (selectedFile != null && selectedFile !in logFiles) {
+            selectedFile = null
+            logContent = emptyList()
+        }
+    }
+    LaunchedEffect(Unit) { refresh() }
+
+    // SAF export launcher
+    val exportLauncher = rememberLauncherForActivityResult(
+        contract = ActivityResultContracts.CreateDocument("text/plain")
+    ) { uri ->
+        if (uri != null && selectedFile != null) {
+            exportLogFile(context, uri, selectedFile!!)
+        }
+    }
+
+    Column(modifier = Modifier.fillMaxSize().padding(16.dp)) {
+        // ── Header ──
+        Row(
+            verticalAlignment = Alignment.CenterVertically,
+            modifier = Modifier.fillMaxWidth()
+        ) {
+            Text("运行日志", style = MaterialTheme.typography.titleMedium, modifier = Modifier.weight(1f))
+            IconButton(onClick = { refresh() }) {
+                Icon(Icons.Filled.Refresh, contentDescription = "刷新")
+            }
+        }
+
+        if (logFiles.isEmpty()) {
+            Text(
+                "暂无日志文件",
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                modifier = Modifier.padding(vertical = 24.dp)
+            )
+        }
+
+        // ── Log file list ──
+        Text("日志文件", style = MaterialTheme.typography.labelLarge)
+        LazyColumn(
+            modifier = Modifier.heightIn(max = 160.dp),
+            verticalArrangement = Arrangement.spacedBy(4.dp)
+        ) {
+            items(logFiles, key = { it.absolutePath }) { file ->
+                val isSelected = file == selectedFile
+                Card(
+                    onClick = {
+                        selectedFile = file
+                        scope.launch {
+                            logContent = withContext(Dispatchers.IO) {
+                                file.readLines()
+                            }
+                        }
+                    },
+                    colors = CardDefaults.cardColors(
+                        containerColor = if (isSelected)
+                            MaterialTheme.colorScheme.primaryContainer
+                        else
+                            MaterialTheme.colorScheme.surfaceVariant
+                    )
+                ) {
+                    Row(
+                        modifier = Modifier.fillMaxWidth().padding(horizontal = 12.dp, vertical = 8.dp),
+                        verticalAlignment = Alignment.CenterVertically
+                    ) {
+                        Text(
+                            text = file.name,
+                            style = MaterialTheme.typography.bodySmall,
+                            modifier = Modifier.weight(1f)
+                        )
+                        Text(
+                            text = "${file.length() / 1024}KB",
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant
+                        )
+                    }
+                }
+            }
+        }
+
+        Spacer(Modifier.height(12.dp))
+
+        // ── Action buttons ──
+        if (selectedFile != null) {
+            Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                OutlinedButton(
+                    onClick = { exportLauncher.launch(selectedFile!!.name) },
+                    modifier = Modifier.weight(1f)
+                ) {
+                    Icon(Icons.Filled.FileDownload, contentDescription = null, modifier = Modifier.size(18.dp))
+                    Spacer(Modifier.width(4.dp))
+                    Text("导出")
+                }
+                OutlinedButton(
+                    onClick = {
+                        selectedFile!!.delete()
+                        refresh()
+                    },
+                    colors = ButtonDefaults.outlinedButtonColors(
+                        contentColor = MaterialTheme.colorScheme.error
+                    ),
+                    modifier = Modifier.weight(1f)
+                ) {
+                    Icon(Icons.Filled.Delete, contentDescription = null, modifier = Modifier.size(18.dp))
+                    Spacer(Modifier.width(4.dp))
+                    Text("删除")
+                }
+            }
+            Spacer(Modifier.height(8.dp))
+
+            // ── Log content ──
+            Text(
+                "日志内容 — ${selectedFile!!.name}",
+                style = MaterialTheme.typography.labelLarge
+            )
+            Surface(
+                modifier = Modifier.fillMaxWidth().weight(1f),
+                color = MaterialTheme.colorScheme.surfaceVariant,
+                shape = MaterialTheme.shapes.small
+            ) {
+                if (logContent.isEmpty()) {
+                    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+                        Text("（空）", color = MaterialTheme.colorScheme.onSurfaceVariant)
+                    }
+                } else {
+                    val scrollState = rememberScrollState()
+                    Column(
+                        modifier = Modifier
+                            .fillMaxSize()
+                            .verticalScroll(scrollState)
+                            .padding(8.dp)
+                    ) {
+                        // Show last 500 lines (newest at bottom)
+                        val displayLines = logContent.takeLast(500)
+                        for (line in displayLines) {
+                            Text(
+                                text = line,
+                                style = MaterialTheme.typography.bodySmall.copy(
+                                    fontFamily = FontFamily.Monospace
+                                ),
+                                color = MaterialTheme.colorScheme.onSurfaceVariant
+                            )
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+private fun exportLogFile(context: Context, uri: Uri, file: File) {
+    try {
+        context.contentResolver.openOutputStream(uri)?.use { out ->
+            file.inputStream().use { `in` ->
+                `in`.copyTo(out)
+            }
+        }
+    } catch (e: Exception) {
+        Log.e("LogScreen", "导出日志失败", e)
+    }
+}

app/src/main/java/com/example/androidbackupgui/ui/RestoreScreen.kt

@@ -1,5 +1,7 @@
 package com.example.androidbackupgui.ui
-
+import android.net.Uri
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.foundation.layout.*
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
@@ -10,6 +12,7 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.unit.dp
 import com.example.androidbackupgui.backup.*
+import com.example.androidbackupgui.backup.defaultResticWrapper
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
@@ -34,6 +37,29 @@ fun RestoreScreen() {
     var availableSnapshots by remember { mutableStateOf<List<ResticWrapper.ResticSnapshot>>(emptyList()) }
     val configFile = remember { File(context.filesDir, "backup_settings.conf") }
 
+    // SAF directory picker for selecting external backup dir
+    val dirPickerLauncher =
+        rememberLauncherForActivityResult(
+            contract = ActivityResultContracts.OpenDocumentTree(),
+        ) { uri ->
+            if (uri != null) {
+                val resolvedPath = resolveSafTreeUri(uri)
+                if (resolvedPath != null) {
+                    val dir = File(resolvedPath)
+                    backupDir = dir
+                    selectedSnapshot = null
+                    scope.launch {
+                        loadFromDir(context, dir) { pkgs, infos, status ->
+                            packages = pkgs
+                            appInfos = infos
+                            selectedPackages = pkgs.toSet()
+                            statusText = status
+                        }
+                    }
+                }
+            }
+        }
+
     // Load config
     LaunchedEffect(Unit) {
         config = BackupConfig.fromFile(configFile)
@@ -46,7 +72,6 @@ fun RestoreScreen() {
         // ── Top controls card ──
         Card(modifier = Modifier.fillMaxWidth().padding(12.dp)) {
             Column(modifier = Modifier.padding(12.dp), verticalArrangement = Arrangement.spacedBy(8.dp)) {
-
                 // Source buttons row
                 Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
                     OutlinedButton(
@@ -54,17 +79,20 @@ fun RestoreScreen() {
                             scope.launch {
                                 try {
                                     val defaultDir = context.filesDir
-                                    val backupDirs = withContext(Dispatchers.IO) {
-                                        defaultDir.listFiles()
-                                            ?.filter { it.isDirectory && it.name.startsWith("Backup_") }
-                                            ?: emptyList()
-                                    }
+                                    val backupDirs =
+                                        withContext(Dispatchers.IO) {
+                                            defaultDir
+                                                .listFiles()
+                                                ?.filter { it.isDirectory && it.name.startsWith("Backup_") }
+                                                ?: emptyList()
+                                        }
                                     if (backupDirs.isNotEmpty()) {
                                         val dir = backupDirs.first()
                                         backupDir = dir
                                         selectedSnapshot = null
                                         loadFromDir(context, dir) { pkgs, infos, status ->
-                                            packages = pkgs; appInfos = infos
+                                            packages = pkgs
+                                            appInfos = infos
                                             selectedPackages = pkgs.toSet()
                                             statusText = status
                                         }
@@ -77,31 +105,54 @@ fun RestoreScreen() {
                             }
                         },
                         enabled = !isRunning,
-                        modifier = Modifier.weight(1f)
+                        modifier = Modifier.weight(1f),
                     ) {
                         Text("本地备份")
                     }
 
+                    OutlinedButton(
+                        onClick = { dirPickerLauncher.launch(null) },
+                        enabled = !isRunning,
+                        modifier = Modifier.weight(1f),
+                    ) {
+                        Text("选择目录")
+                    }
+
                     Button(
                         onClick = {
-                            val config = resticConfig ?: run {
-                                statusText = "未配置 Restic，请先在设置中配置"
-                                return@Button
-                            }
+                            val config =
+                                resticConfig ?: run {
+                                    statusText = "未配置 Restic，请先在设置中配置"
+                                    return@Button
+                                }
                             scope.launch {
                                 isRunning = true
                                 statusText = "正在读取快照…"
                                 try {
-                                    val result = withContext(Dispatchers.IO) {
-                                        ResticWrapper.listSnapshots(
-                                            config.resticRepo, config.resticPassword,
-                                            backend = config.resticBackend,
-                                            backendUrl = config.resticBackendUrl,
-                                            backendUser = config.resticBackendUser,
-                                            backendPass = config.resticBackendPass,
-                                            backendShare = config.resticBackendShare,
-                                        )
-                                    }
+                                    // 配置 ResticWrapper 环境
+                                    defaultResticWrapper.cacheDir = context.cacheDir.absolutePath
+                                    defaultResticWrapper.backendDomain = config.resticBackendDomain
+                                    ResticBinary.prepare(context)?.let { defaultResticWrapper.binaryPath = it }
+
+                                    // 从 PasswordManager 恢复密码（过滤掉占位符）
+                                    fun configPw(
+                                        key: String?,
+                                        fallback: String,
+                                    ): String = key?.takeIf { it.isNotEmpty() && it != "stored-in-keystore" } ?: fallback
+                                    val realPassword = configPw(PasswordManager.getResticPassword(), config.resticPassword)
+                                    val realBackendPass = configPw(PasswordManager.getBackendPass(), config.resticBackendPass)
+                                    val result =
+                                        withContext(Dispatchers.IO) {
+                                            defaultResticWrapper.listSnapshots(
+                                                config.resticRepo,
+                                                realPassword,
+                                                backend = config.resticBackend,
+                                                backendUrl = config.resticBackendUrl,
+                                                backendUser = config.resticBackendUser,
+                                                backendPass = realBackendPass,
+                                                backendShare = config.resticBackendShare,
+                                            )
+                                        }
                                     if (result.isFailure) {
                                         statusText = "读取快照失败: ${result.exceptionOrNull()?.message}"
                                         return@launch
@@ -114,9 +165,12 @@ fun RestoreScreen() {
                                     availableSnapshots = snaps
                                     if (snaps.size == 1) {
                                         loadResticSnapshot(context, snaps.first(), resticConfig!!) { pkgs, infos, status ->
-                                            backupDir = null; selectedSnapshot = snaps.first()
-                                            packages = pkgs; appInfos = infos
-                                            selectedPackages = pkgs.toSet(); statusText = status
+                                            backupDir = null
+                                            selectedSnapshot = snaps.first()
+                                            packages = pkgs
+                                            appInfos = infos
+                                            selectedPackages = pkgs.toSet()
+                                            statusText = status
                                         }
                                     } else {
                                         showSnapshotPicker = true
@@ -129,21 +183,26 @@ fun RestoreScreen() {
                             }
                         },
                         enabled = !isRunning && resticConfig != null,
-                        modifier = Modifier.weight(1f)
+                        modifier = Modifier.weight(1f),
                     ) {
                         Text("Restic 快照")
                     }
                 }
 
                 // Source info text
-                val sourceText = if (backupDir != null) backupDir!!.absolutePath
-                else if (selectedSnapshot != null) "restic: ${selectedSnapshot!!.time.take(19)}"
-                else ""
+                val sourceText =
+                    if (backupDir != null) {
+                        backupDir!!.absolutePath
+                    } else if (selectedSnapshot != null) {
+                        "restic: ${selectedSnapshot!!.time.take(19)}"
+                    } else {
+                        ""
+                    }
                 if (sourceText.isNotEmpty()) {
                     Text(
                         text = sourceText,
                         style = MaterialTheme.typography.bodySmall,
-                        color = MaterialTheme.colorScheme.onSurfaceVariant
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
                     )
                 }
             }
@@ -154,46 +213,54 @@ fun RestoreScreen() {
             text = statusText,
             style = MaterialTheme.typography.bodySmall,
             color = MaterialTheme.colorScheme.onSurfaceVariant,
-            modifier = Modifier.padding(horizontal = 12.dp, vertical = 4.dp)
+            modifier = Modifier.padding(horizontal = 12.dp, vertical = 4.dp),
         )
 
         // ── App list ──
         LazyColumn(
             modifier = Modifier.weight(1f).fillMaxWidth(),
             contentPadding = PaddingValues(horizontal = 12.dp, vertical = 4.dp),
-            verticalArrangement = Arrangement.spacedBy(4.dp)
+            verticalArrangement = Arrangement.spacedBy(4.dp),
         ) {
             items(appInfos, key = { it.packageName.value }) { app ->
                 Card(
                     onClick = {
                         val pkg = app.packageName.value
-                        selectedPackages = if (pkg in selectedPackages) selectedPackages - pkg
-                        else selectedPackages + pkg
+                        selectedPackages =
+                            if (pkg in selectedPackages) {
+                                selectedPackages - pkg
+                            } else {
+                                selectedPackages + pkg
+                            }
                     },
-                    modifier = Modifier.fillMaxWidth()
+                    modifier = Modifier.fillMaxWidth(),
                 ) {
                     Row(
                         modifier = Modifier.padding(12.dp),
-                        verticalAlignment = Alignment.CenterVertically
+                        verticalAlignment = Alignment.CenterVertically,
                     ) {
                         Checkbox(
                             checked = app.packageName.value in selectedPackages,
                             onCheckedChange = { checked ->
                                 val pkg = app.packageName.value
-                                selectedPackages = if (checked) selectedPackages + pkg
-                                else selectedPackages - pkg
-                            }
+                                selectedPackages =
+                                    if (checked) {
+                                        selectedPackages + pkg
+                                    } else {
+                                        selectedPackages - pkg
+                                    }
+                            },
                         )
                         Spacer(Modifier.width(8.dp))
                         Column {
                             Text(
                                 text = app.label.ifEmpty { app.packageName.value },
-                                style = MaterialTheme.typography.bodyLarge
+                                style = MaterialTheme.typography.bodyLarge,
                             )
                             Text(
                                 text = app.packageName.value,
                                 style = MaterialTheme.typography.bodySmall,
-                                color = MaterialTheme.colorScheme.onSurfaceVariant
+                                color = MaterialTheme.colorScheme.onSurfaceVariant,
                             )
                         }
                     }
@@ -221,19 +288,26 @@ fun RestoreScreen() {
 
                                 try {
                                     statusText = "正在从 restic 快照恢复…"
-                                    val restoreResult = withContext(Dispatchers.IO) {
-                                        ResticWrapper.restore(
-                                            repoPath = config.resticRepo,
-                                            password = config.resticPassword,
-                                            snapshotId = snapshot.id,
-                                            targetPath = staging.absolutePath,
-                                            backend = config.resticBackend,
-                                            backendUrl = config.resticBackendUrl,
-                                            backendUser = config.resticBackendUser,
-                                            backendPass = config.resticBackendPass,
-                                            backendShare = config.resticBackendShare,
-                                        )
-                                    }
+                                    val restoreResult =
+                                        withContext(Dispatchers.IO) {
+                                            val rPw =
+                                                PasswordManager.getResticPassword()?.takeIf { it != "stored-in-keystore" }
+                                                    ?: config.resticPassword
+                                            val rBpw =
+                                                PasswordManager.getBackendPass()?.takeIf { it != "stored-in-keystore" }
+                                                    ?: config.resticBackendPass
+                                            defaultResticWrapper.restore(
+                                                repoPath = config.resticRepo,
+                                                password = rPw,
+                                                snapshotId = snapshot.id,
+                                                targetPath = staging.absolutePath,
+                                                backend = config.resticBackend,
+                                                backendUrl = config.resticBackendUrl,
+                                                backendUser = config.resticBackendUser,
+                                                backendPass = rBpw,
+                                                backendShare = config.resticBackendShare,
+                                            )
+                                        }
                                     if (restoreResult.isFailure) {
                                         statusText = "restic 恢复失败: ${restoreResult.exceptionOrNull()?.message}"
                                         return@launch
@@ -241,45 +315,54 @@ fun RestoreScreen() {
                                     val restoredDir = File(staging, backupPath.removePrefix("/"))
                                     statusText = "正在从恢复的备份安装应用…"
 
-                                    val result = withContext(Dispatchers.IO) {
+                                    val result =
+                                        withContext(Dispatchers.IO) {
+                                            RestoreOperation.restoreApps(
+                                                context = context,
+                                                backupDir = restoredDir,
+                                                userId = config.backupUserId.toString(),
+                                                filterPkgs = selectedPackages,
+                                                onProgress = { progress ->
+                                                    statusText =
+                                                        "[${progress.current}/${progress.total}] ${progress.packageName}: ${progress.message}"
+                                                },
+                                            )
+                                        }
+                                    WifiManager.restore(restoredDir)
+                                    statusText =
+                                        buildString {
+                                            appendLine("恢复完成！")
+                                            appendLine("成功: ${result.successCount} 失败: ${result.failCount}")
+                                            append("耗时: ${result.elapsedMs / 1000}秒")
+                                        }
+                                } finally {
+                                    try {
+                                        staging.deleteRecursively()
+                                    } catch (_: Exception) {
+                                    }
+                                }
+                            } else if (backupDir != null) {
+                                val dir = backupDir!!
+                                val result =
+                                    withContext(Dispatchers.IO) {
                                         RestoreOperation.restoreApps(
                                             context = context,
-                                            backupDir = restoredDir,
+                                            backupDir = dir,
                                             userId = config.backupUserId.toString(),
                                             filterPkgs = selectedPackages,
                                             onProgress = { progress ->
-                                                statusText = "[${progress.current}/${progress.total}] ${progress.packageName}: ${progress.message}"
-                                            }
+                                                statusText =
+                                                    "[${progress.current}/${progress.total}] ${progress.packageName}: ${progress.message}"
+                                            },
                                         )
                                     }
-                                    WifiManager.restore(restoredDir)
-                                    statusText = buildString {
+                                WifiManager.restore(dir)
+                                statusText =
+                                    buildString {
                                         appendLine("恢复完成！")
                                         appendLine("成功: ${result.successCount} 失败: ${result.failCount}")
                                         append("耗时: ${result.elapsedMs / 1000}秒")
                                     }
-                                } finally {
-                                    try { staging.deleteRecursively() } catch (_: Exception) {}
-                                }
-                            } else if (backupDir != null) {
-                                val dir = backupDir!!
-                                val result = withContext(Dispatchers.IO) {
-                                    RestoreOperation.restoreApps(
-                                        context = context,
-                                        backupDir = dir,
-                                        userId = config.backupUserId.toString(),
-                                        filterPkgs = selectedPackages,
-                                        onProgress = { progress ->
-                                            statusText = "[${progress.current}/${progress.total}] ${progress.packageName}: ${progress.message}"
-                                        }
-                                    )
-                                }
-                                WifiManager.restore(dir)
-                                statusText = buildString {
-                                    appendLine("恢复完成！")
-                                    appendLine("成功: ${result.successCount} 失败: ${result.failCount}")
-                                    append("耗时: ${result.elapsedMs / 1000}秒")
-                                }
                             }
                         } catch (e: Exception) {
                             statusText = "恢复异常: ${e.message}"
@@ -289,7 +372,7 @@ fun RestoreScreen() {
                     }
                 },
                 enabled = !isRunning && selectedPackages.isNotEmpty() && (backupDir != null || selectedSnapshot != null),
-                modifier = Modifier.fillMaxWidth().padding(12.dp)
+                modifier = Modifier.fillMaxWidth().padding(12.dp),
             ) {
                 if (isRunning) {
                     CircularProgressIndicator(modifier = Modifier.size(16.dp))
@@ -314,59 +397,69 @@ fun RestoreScreen() {
                                 showSnapshotPicker = false
                                 scope.launch {
                                     loadResticSnapshot(context, snap, resticConfig!!) { pkgs, infos, status ->
-                                        backupDir = null; selectedSnapshot = snap
-                                        packages = pkgs; appInfos = infos
-                                        selectedPackages = pkgs.toSet(); statusText = status
+                                        backupDir = null
+                                        selectedSnapshot = snap
+                                        packages = pkgs
+                                        appInfos = infos
+                                        selectedPackages = pkgs.toSet()
+                                        statusText = status
                                     }
                                 }
                             },
-                            modifier = Modifier.fillMaxWidth()
+                            modifier = Modifier.fillMaxWidth(),
                         ) { Text(label) }
                     }
                 }
             },
             confirmButton = {
                 TextButton(onClick = { showSnapshotPicker = false }) { Text("取消") }
-            }
+            },
         )
     }
 }
 
-// ── Sub-composables ──
-
-// ── Helper functions ──
-
 private suspend fun loadFromDir(
     context: android.content.Context,
     dir: File,
-    onResult: (packages: List<String>, appInfos: List<AppInfo>, status: String) -> Unit
+    onResult: (packages: List<String>, appInfos: List<AppInfo>, status: String) -> Unit,
 ) {
     withContext(Dispatchers.IO) {
         val appListFile = File(dir, "appList.txt")
-        val pkgs = if (appListFile.exists()) {
-            appListFile.readLines()
-                .map { it.trim() }
-                .filter { it.isNotEmpty() && !it.startsWith("#") }
-        } else {
-            dir.listFiles()
-                ?.filter { it.isDirectory }
-                ?.map { it.name }
-                ?: emptyList()
-        }
+        val pkgs =
+            BackupOperation.readTextFile(appListFile)?.let { content ->
+                content.lines().map { it.trim() }.filter { it.isNotEmpty() && !it.startsWith("#") }
+            } ?: run {
+                BackupOperation.listBackupFiles(dir)
+                    ?: emptyList()
+            }
+        // Filter to only apps that have actual backup data (at least one APK)
+        val validPkgs =
+            pkgs.filter { pkg ->
+                val appDir = File(dir, pkg)
+                val files = BackupOperation.listBackupFiles(appDir)
+                files?.any { it.endsWith(".apk") } == true
+            }
+        val skipped = pkgs.size - validPkgs.size
         // Read cached labels from app_details.json (includes uninstalled apps)
         val cachedLabels = readLocalAppDetails(dir)
-        val preLabeled = pkgs.map { pkg ->
-            AppInfo(packageName = PackageName(pkg), label = cachedLabels[pkg] ?: "")
-        }
+        val preLabeled =
+            validPkgs.map { pkg ->
+                AppInfo(packageName = PackageName(pkg), label = cachedLabels[pkg] ?: "")
+            }
         // Resolve labels for currently installed apps, keep cached labels for uninstalled
         val resolved = AppScanner.resolveLabels(context, preLabeled)
         // For apps that resolveLabels fell back to package name, restore cached label
-        val infos = resolved.map { app ->
-            val cachedLabel = cachedLabels[app.packageName.value]
-            if (cachedLabel != null && app.label == app.packageName.value) app.copy(label = cachedLabel)
-            else app
-        }
-        onResult(pkgs, infos, "共 ${pkgs.size} 个备份应用")
+        val infos =
+            resolved.map { app ->
+                val cachedLabel = cachedLabels[app.packageName.value]
+                if (cachedLabel != null && app.label == app.packageName.value) {
+                    app.copy(label = cachedLabel)
+                } else {
+                    app
+                }
+            }
+        val suffix = if (skipped > 0) "（${skipped}个应用备份数据缺失已自动跳过）" else ""
+        onResult(validPkgs, infos, "共 ${validPkgs.size} 个备份应用$suffix")
     }
 }
 
@@ -374,71 +467,126 @@ private suspend fun loadResticSnapshot(
     context: android.content.Context,
     snapshot: ResticWrapper.ResticSnapshot,
     config: BackupConfig,
-    onResult: (packages: List<String>, appInfos: List<AppInfo>, status: String) -> Unit
+    onResult: (packages: List<String>, appInfos: List<AppInfo>, status: String) -> Unit,
 ) {
-    val backupPath = snapshot.paths.firstOrNull() ?: run {
-        onResult(emptyList(), emptyList(), "快照中找不到备份路径")
-        return
-    }
-    val dumpResult = ResticWrapper.dump(
-        config.resticRepo, config.resticPassword,
-        snapshot.id, "$backupPath/appList.txt",
-        backend = config.resticBackend,
-        backendUrl = config.resticBackendUrl,
-        backendUser = config.resticBackendUser,
-        backendPass = config.resticBackendPass,
-        backendShare = config.resticBackendShare,
-    )
-    val content = dumpResult.getOrNull()
+    val backupPath =
+        snapshot.paths.firstOrNull() ?: run {
+            onResult(emptyList(), emptyList(), "快照中找不到备份路径")
+            return
+        }
+
+    fun rp(
+        key: String?,
+        fallback: String,
+    ) = key?.takeIf { it.isNotEmpty() && it != "stored-in-keystore" } ?: fallback
+    val realPassword = rp(PasswordManager.getResticPassword(), config.resticPassword)
+    val realBackendPass = rp(PasswordManager.getBackendPass(), config.resticBackendPass)
+
+    suspend fun tryDump(path: String) =
+        defaultResticWrapper
+            .dump(
+                config.resticRepo,
+                realPassword,
+                snapshot.id,
+                path,
+                backend = config.resticBackend,
+                backendUrl = config.resticBackendUrl,
+                backendUser = config.resticBackendUser,
+                backendPass = realBackendPass,
+                backendShare = config.resticBackendShare,
+            ).getOrNull()
+    // 兼容流式备份（新版：根目录，旧版：meta/）和普通备份
+    val content =
+        tryDump("$backupPath/appList.txt")
+            ?: tryDump("$backupPath/meta/appList.txt")
     if (content == null) {
         onResult(emptyList(), emptyList(), "无法从快照读取应用列表")
         return
     }
-    val pkgs = content.lines()
-        .map { it.trim() }
-        .filter { it.isNotEmpty() && !it.startsWith("#") }
+    val pkgs =
+        content
+            .lines()
+            .map { it.trim() }
+            .filter { it.isNotEmpty() && !it.startsWith("#") }
 
     // Read cached labels from app_details.json in the snapshot
     val cachedLabels = loadResticAppDetails(config, snapshot.id, backupPath)
-    val preLabeled = pkgs.map { pkg ->
-        AppInfo(packageName = PackageName(pkg), label = cachedLabels[pkg] ?: "")
-    }
+    val preLabeled =
+        pkgs.map { pkg ->
+            AppInfo(packageName = PackageName(pkg), label = cachedLabels[pkg] ?: "")
+        }
     val resolved = AppScanner.resolveLabels(context, preLabeled)
-    val infos = resolved.map { app ->
-        val cachedLabel = cachedLabels[app.packageName.value]
-        if (cachedLabel != null && app.label == app.packageName.value) app.copy(label = cachedLabel)
-        else app
-    }
+    val infos =
+        resolved.map { app ->
+            val cachedLabel = cachedLabels[app.packageName.value]
+            if (cachedLabel != null && app.label == app.packageName.value) {
+                app.copy(label = cachedLabel)
+            } else {
+                app
+            }
+        }
     onResult(pkgs, infos, "restic 快照共 ${pkgs.size} 个应用")
 }
 
 /** Read app_details.json from a local backup directory and return a package→label map. */
-private suspend fun readLocalAppDetails(dir: File): Map<String, String> = withContext(Dispatchers.IO) {
-    val metaFile = File(dir, "app_details.json")
-    if (!metaFile.exists()) return@withContext emptyMap()
-    try {
-        val json = metaFile.readText()
-        ResticWrapper.parseAppDetailsJson(json).mapValues { it.value.label }
-    } catch (_: Exception) { emptyMap() }
-}
+private suspend fun readLocalAppDetails(dir: File): Map<String, String> =
+    withContext(Dispatchers.IO) {
+        val metaFile = File(dir, "app_details.json")
+        val json = BackupOperation.readTextFile(metaFile) ?: return@withContext emptyMap()
+        try {
+            defaultResticWrapper.parseAppDetailsJson(json).mapValues { it.value.label }
+        } catch (_: Exception) {
+            emptyMap()
+        }
+    }
 
 /** Dump app_details.json from a restic snapshot and return a package→label map. */
 private suspend fun loadResticAppDetails(
     config: BackupConfig,
     snapshotId: String,
-    backupPath: String
+    backupPath: String,
 ): Map<String, String> {
-    val dumpResult = ResticWrapper.dump(
-        config.resticRepo, config.resticPassword,
-        snapshotId, "$backupPath/app_details.json",
-        backend = config.resticBackend,
-        backendUrl = config.resticBackendUrl,
-        backendUser = config.resticBackendUser,
-        backendPass = config.resticBackendPass,
-        backendShare = config.resticBackendShare,
-    )
-    val json = dumpResult.getOrNull() ?: return emptyMap()
+    fun rp2(
+        key: String?,
+        fallback: String,
+    ) = key?.takeIf { it.isNotEmpty() && it != "stored-in-keystore" } ?: fallback
+    val realPassword = rp2(PasswordManager.getResticPassword(), config.resticPassword)
+    val realBackendPass = rp2(PasswordManager.getBackendPass(), config.resticBackendPass)
+
+    suspend fun tryDump(path: String) =
+        defaultResticWrapper
+            .dump(
+                config.resticRepo,
+                realPassword,
+                snapshotId,
+                path,
+                backend = config.resticBackend,
+                backendUrl = config.resticBackendUrl,
+                backendUser = config.resticBackendUser,
+                backendPass = realBackendPass,
+                backendShare = config.resticBackendShare,
+            ).getOrNull()
+    val json =
+        tryDump("$backupPath/app_details.json")
+            ?: tryDump("$backupPath/meta/app_details.json")
+            ?: return emptyMap()
     return try {
-        ResticWrapper.parseAppDetailsJson(json).mapValues { it.value.label }
-    } catch (_: Exception) { emptyMap() }
+        defaultResticWrapper.parseAppDetailsJson(json).mapValues { it.value.label }
+    } catch (_: Exception) {
+        emptyMap()
+    }
+}
+
+/** Convert SAF tree URI to a filesystem path. */
+private fun resolveSafTreeUri(uri: Uri): String? {
+    val docId = uri.lastPathSegment?.let { java.net.URLDecoder.decode(it, "UTF-8") } ?: return null
+    val colonIdx = docId.indexOf(':')
+    if (colonIdx < 0) return null
+    val storageId = docId.substring(0, colonIdx)
+    val relPath = docId.substring(colonIdx + 1).trim('/')
+    return if (storageId.equals("primary", ignoreCase = true)) {
+        "/storage/emulated/0/$relPath"
+    } else {
+        "/storage/$storageId/$relPath"
+    }
 }

app/src/test/java/com/example/androidbackupgui/backup/AppResultTest.kt

@@ -0,0 +1,88 @@
+package com.example.androidbackupgui.backup
+
+import io.kotest.assertions.throwables.shouldThrow
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.nulls.shouldBeNull
+import io.kotest.matchers.nulls.shouldNotBeNull
+import io.kotest.matchers.shouldBe
+import io.kotest.matchers.types.shouldBeInstanceOf
+
+class AppResultTest :
+    FunSpec({
+
+        context("AppResult.Success") {
+            test("holds value correctly") {
+                val result: AppResult<String> = AppResult.Success("hello")
+                result.isSuccess shouldBe true
+                result.isFailure shouldBe false
+                result.getOrNull() shouldBe "hello"
+                result.getOrDefault("default") shouldBe "hello"
+            }
+
+            test("fold maps success branch") {
+                val result: AppResult<Int> = AppResult.Success(42)
+                val output = result.fold({ it * 2 }, { -1 })
+                output shouldBe 84
+            }
+
+            test("map transforms value") {
+                val result = AppResult.Success(42)
+                val mapped = result.map { it.toString() }
+                mapped.shouldBeInstanceOf<AppResult.Success<String>>()
+                mapped.getOrNull() shouldBe "42"
+            }
+
+            test("getOrThrow returns value") {
+                val result = AppResult.Success(99)
+                result.getOrThrow() shouldBe 99
+            }
+        }
+
+        context("AppResult.Failure") {
+            val error = AppError.Network("connection lost")
+
+            test("holds error correctly") {
+                val result: AppResult<Int> = AppResult.Failure(error)
+                result.isSuccess shouldBe false
+                result.isFailure shouldBe true
+                result.getOrNull().shouldBeNull()
+                result.getOrDefault(0) shouldBe 0
+                result.errorOrNull() shouldBe error
+            }
+
+            test("fold maps failure branch") {
+                val result: AppResult<Int> = AppResult.Failure(error)
+                val output = result.fold({ it }, { err -> -1 })
+                output shouldBe -1
+            }
+
+            test("map passes through failure") {
+                val result: AppResult<Int> = AppResult.Failure(error)
+                val mapped = result.map { it * 2 }
+                mapped.shouldBeInstanceOf<AppResult.Failure>()
+                mapped.errorOrNull() shouldBe error
+            }
+
+            test("getOrThrow throws") {
+                val result = AppResult.Failure(error)
+                shouldThrow<RuntimeException> { result.getOrThrow() }
+            }
+
+            test("mapError transforms the error") {
+                val result: AppResult<Int> = AppResult.Failure(error)
+                val mapped = result.mapError { AppError.Parse("wrapped: ${it.message}") }
+                mapped.shouldBeInstanceOf<AppResult.Failure>()
+                (mapped.errorOrNull() as? AppError.Parse)?.let {
+                    it.message shouldBe "wrapped: connection lost"
+                }
+            }
+        }
+
+        context("err helper") {
+            test("creates Failure") {
+                val result = err<String>(AppError.Cancelled)
+                result.shouldBeInstanceOf<AppResult.Failure>()
+                result.errorOrNull() shouldBe AppError.Cancelled
+            }
+        }
+    })

app/src/test/java/com/example/androidbackupgui/backup/BackupConfigTest.kt

@@ -4,59 +4,41 @@ import io.kotest.core.spec.style.FunSpec
 import io.kotest.matchers.shouldBe
 import java.io.File
 
-class BackupConfigTest : FunSpec({
+class BackupConfigTest :
+    FunSpec({
 
-    // Helper: write config to temp file, read it back
-    fun roundTrip(config: BackupConfig): BackupConfig {
-        val tmp = File.createTempFile("cfg_test", ".conf")
-        try {
-            BackupConfig.toFile(config, tmp)
-            return BackupConfig.fromFile(tmp)
-        } finally {
-            tmp.delete()
+        // Helper: write config to temp file, read it back
+        fun roundTrip(config: BackupConfig): BackupConfig {
+            val tmp = File.createTempFile("cfg_test", ".conf")
+            try {
+                BackupConfig.toFile(config, tmp)
+                return BackupConfig.fromFile(tmp)
+            } finally {
+                tmp.delete()
+            }
         }
-    }
 
-    test("plain password survives round trip") {
-        val c = BackupConfig(resticPassword = "simple123")
-        roundTrip(c).resticPassword shouldBe "simple123"
-    }
+        test("password is stored as placeholder (actual password in PasswordManager)") {
+            val c = BackupConfig(resticPassword = "simple123")
+            // Password is no longer in config file; toFile writes "stored-in-keystore"
+            roundTrip(c).resticPassword shouldBe ""
+        }
 
-    test("password with double-quote survives round trip") {
-        val c = BackupConfig(resticPassword = "pa\"ss\"word")
-        roundTrip(c).resticPassword shouldBe "pa\"ss\"word"
-    }
+        test("backend pass is stored as placeholder (actual pass in PasswordManager)") {
+            val c = BackupConfig(resticBackendPass = "secret")
+            roundTrip(c).resticBackendPass shouldBe ""
+        }
 
-    test("password with backslash survives round trip") {
-        val c = BackupConfig(resticPassword = "p\\a\\ss")
-        roundTrip(c).resticPassword shouldBe "p\\a\\ss"
-    }
+        test("output path with spaces survives round trip") {
+            val c = BackupConfig(outputPath = "/sdcard/my backups/")
+            roundTrip(c).outputPath shouldBe "/sdcard/my backups/"
+        }
 
-    test("password with leading and trailing spaces survives round trip") {
-        val c = BackupConfig(resticPassword = " sp ace ")
-        roundTrip(c).resticPassword shouldBe " sp ace "
-    }
-
-    test("password with special shell characters survives round trip") {
-        val c = BackupConfig(resticPassword = "p@\$s#w!ord&")
-        roundTrip(c).resticPassword shouldBe "p@\$s#w!ord&"
-    }
-
-    test("restic_backend_pass with quote and backslash survives round trip") {
-        val c = BackupConfig(resticBackendPass = "a\\\"b")
-        roundTrip(c).resticBackendPass shouldBe "a\\\"b"
-    }
-
-    test("output path with spaces survives round trip") {
-        val c = BackupConfig(outputPath = "/sdcard/my backups/")
-        roundTrip(c).outputPath shouldBe "/sdcard/my backups/"
-    }
-
-    test("non-restic fields are unaffected") {
-        val c = BackupConfig(backupMode = 1, backupWifi = 0, compressionMethod = "zstd")
-        val out = roundTrip(c)
-        out.backupMode shouldBe 1
-        out.backupWifi shouldBe 0
-        out.compressionMethod shouldBe "zstd"
-    }
-})
+        test("non-restic fields are unaffected") {
+            val c = BackupConfig(backupMode = 1, backupWifi = 0, compressionMethod = "zstd")
+            val out = roundTrip(c)
+            out.backupMode shouldBe 1
+            out.backupWifi shouldBe 0
+            out.compressionMethod shouldBe "zstd"
+        }
+    })

app/src/test/java/com/example/androidbackupgui/backup/PackageNameTest.kt

@@ -0,0 +1,69 @@
+package com.example.androidbackupgui.backup
+
+import io.kotest.assertions.throwables.shouldThrow
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.nulls.shouldBeNull
+import io.kotest.matchers.nulls.shouldNotBeNull
+import io.kotest.matchers.shouldBe
+
+class PackageNameTest :
+    FunSpec({
+
+        context("PackageName constructor validation") {
+            test("accepts valid package names") {
+                PackageName("com.example.app").value shouldBe "com.example.app"
+                PackageName("com.google.android.gms").value shouldBe "com.google.android.gms"
+                PackageName("a.b").value shouldBe "a.b"
+                PackageName("com.example.app_v2.test").value shouldBe "com.example.app_v2.test"
+                PackageName("org.koin.android").value shouldBe "org.koin.android"
+            }
+
+            test("rejects blank package names") {
+                shouldThrow<IllegalArgumentException> { PackageName("") }
+                shouldThrow<IllegalArgumentException> { PackageName("  ") }
+            }
+
+            test("rejects package names without dots") {
+                shouldThrow<IllegalArgumentException> { PackageName("simple") }
+                shouldThrow<IllegalArgumentException> { PackageName("no_dot_at_all") }
+            }
+
+            test("rejects package names with invalid characters") {
+                shouldThrow<IllegalArgumentException> { PackageName("com.example .app") }
+                shouldThrow<IllegalArgumentException> { PackageName("com.example/app") }
+                shouldThrow<IllegalArgumentException> { PackageName("com.example\napp") }
+            }
+
+            test("rejects package names starting with dot") {
+                shouldThrow<IllegalArgumentException> { PackageName(".com.example") }
+            }
+
+            test("rejects package names ending with dot") {
+                shouldThrow<IllegalArgumentException> { PackageName("com.example.") }
+            }
+        }
+
+        context("PackageName.safe") {
+            test("returns PackageName for valid input") {
+                PackageName.safe("com.example.app").shouldNotBeNull()
+                PackageName.safe("a.b").shouldNotBeNull()
+            }
+
+            test("returns null for invalid input instead of throwing") {
+                PackageName.safe("").shouldBeNull()
+                PackageName.safe("no_dots").shouldBeNull()
+                PackageName.safe("with space").shouldBeNull()
+                PackageName.safe("with/slash").shouldBeNull()
+            }
+        }
+
+        context("PackageName equality and toString") {
+            test("value equality works") {
+                PackageName("com.example.app") shouldBe PackageName("com.example.app")
+            }
+
+            test("toString returns the package name") {
+                PackageName("com.example.app").toString() shouldBe "com.example.app"
+            }
+        }
+    })