111

lib/services/sync/auto_backup_service.dart

@@ -80,7 +80,7 @@ class AutoBackupService {
       // 导出数据
       final result = await BackupService.instance.exportDataForAutoBackup();
 
-      if (!result.success) {
+      if (!result.success || result.zipPath == null) {
         debugPrint('AutoBackup: 导出失败 - ${result.errorMessage}');
         return;
       }
@@ -89,8 +89,9 @@ class AutoBackupService {
       final fileName = 'auto_backup_${_formatDateTime(DateTime.now())}.zip';
       final backupFile = File(path.join(backupDir.path, fileName));
 
-      // 写入备份文件
+      // 移动临时 zip 到备份目录
-      await backupFile.writeAsBytes(result.zipBytes!);
+      final tempFile = File(result.zipPath!);
+      await tempFile.rename(backupFile.path);
 
       debugPrint('AutoBackup: 备份成功 - ${backupFile.path}');
       

lib/services/sync/backup_service.dart

@@ -158,13 +158,9 @@ class BackupService {
 
       encoder.close();
 
-      // 读取最终 zip 文件
+      // 返回 zip 文件路径，不再读入内存
-      final zipFile = File(tempZipPath);
-      final zipBytes = await zipFile.readAsBytes();
-      await zipFile.delete();
-
       return _ExportData(
-        zipBytes: Uint8List.fromList(zipBytes),
+        zipPath: tempZipPath,
         movieCount: movies.length,
         bookCount: books.length,
         noteCount: notes.length,
@@ -184,31 +180,36 @@ class BackupService {
   Future<ExportResult> exportDataWithImages() async {
     try {
       final data = await _buildExportData();
+      final zipFile = File(data.zipPath!);
       final tempDir = await getTemporaryDirectory();
       final fileName = 'mooknote_backup_${_formatDateTime(DateTime.now())}.zip';
       final tempFilePath = path.join(tempDir.path, fileName);
-      await File(tempFilePath).writeAsBytes(data.zipBytes);
 
       String? finalPath;
       try {
+        // FilePicker.saveFile 需要 bytes，这里必须读入内存
+        final zipBytes = await zipFile.readAsBytes();
         final outputPath = await FilePicker.platform.saveFile(
           dialogTitle: '保存备份文件',
           fileName: fileName,
           type: FileType.custom,
           allowedExtensions: ['zip'],
-          bytes: data.zipBytes,
+          bytes: zipBytes,
         );
         if (outputPath == null) {
+          await zipFile.delete();
           return ExportResult.cancelled();
         }
         finalPath = outputPath;
-        if (finalPath != tempFilePath) {
-          await File(finalPath).writeAsBytes(data.zipBytes);
-        }
       } catch (e) {
+        // FilePicker 不可用时，复制到临时目录
+        await zipFile.copy(tempFilePath);
         finalPath = tempFilePath;
       }
 
+      // 清理原始临时 zip
+      try { await zipFile.delete(); } catch (_) {}
+
       return ExportResult.success(
         filePath: finalPath,
         movieCount: data.movieCount,
@@ -229,12 +230,12 @@ class BackupService {
 
   // ─── 自动备份导出 ─────────────────────────────────────
 
-  /// 导出数据用于自动备份（返回字节数据）
+  /// 导出数据用于自动备份（返回临时 zip 文件路径，调用方负责删除）
   Future<AutoBackupExportResult> exportDataForAutoBackup() async {
     try {
       final data = await _buildExportData();
       return AutoBackupExportResult.success(
-        zipBytes: data.zipBytes,
+        zipPath: data.zipPath!,
         movieCount: data.movieCount,
         bookCount: data.bookCount,
         noteCount: data.noteCount,
@@ -776,7 +777,7 @@ class BackupService {
 
 /// 导出中间数据
 class _ExportData {
-  final Uint8List zipBytes;
+  final String? zipPath; // 临时 zip 文件路径，调用方负责删除
   final int movieCount;
   final int bookCount;
   final int noteCount;
@@ -784,7 +785,7 @@ class _ExportData {
   final int epubCount;
 
   _ExportData({
-    required this.zipBytes,
+    this.zipPath,
     required this.movieCount,
     required this.bookCount,
     required this.noteCount,
@@ -798,7 +799,7 @@ class _ExportData {
 class AutoBackupExportResult {
   final bool success;
   final String? errorMessage;
-  final Uint8List? zipBytes;
+  final String? zipPath; // 临时 zip 文件路径，调用方负责删除
   final int movieCount;
   final int bookCount;
   final int noteCount;
@@ -808,7 +809,7 @@ class AutoBackupExportResult {
   AutoBackupExportResult._({
     required this.success,
     this.errorMessage,
-    this.zipBytes,
+    this.zipPath,
     this.movieCount = 0,
     this.bookCount = 0,
     this.noteCount = 0,
@@ -817,7 +818,7 @@ class AutoBackupExportResult {
   });
 
   factory AutoBackupExportResult.success({
-    required Uint8List zipBytes,
+    required String zipPath,
     required int movieCount,
     required int bookCount,
     required int noteCount,
@@ -825,7 +826,7 @@ class AutoBackupExportResult {
     int epubCount = 0,
   }) {
     return AutoBackupExportResult._(
-      success: true, zipBytes: zipBytes,
+      success: true, zipPath: zipPath,
       movieCount: movieCount, bookCount: bookCount,
       noteCount: noteCount, imageCount: imageCount,
       epubCount: epubCount,

lib/services/sync/webdav_service.dart

@@ -222,13 +222,15 @@ class WebDAVService {
       try {
         if (direction == SyncDirection.upload) {
           final exportResult = await BackupService.instance.exportDataForAutoBackup();
-          if (!exportResult.success || exportResult.zipBytes == null) {
+          if (!exportResult.success || exportResult.zipPath == null) {
             return SyncResult(success: false, message: exportResult.errorMessage ?? '创建备份失败');
           }
 
           final fileName = _generateBackupFileName();
           final zipUrl = '$dirUrl/$fileName';
-          final success = await _uploadBytes(client, zipUrl, username, password, exportResult.zipBytes!);
+          final success = await _uploadFile(client, zipUrl, username, password, exportResult.zipPath!);
+          // 清理临时 zip 文件
+          try { await File(exportResult.zipPath!).delete(); } catch (_) {}
           if (success) {
             uploadedFiles = 1;
             uploadedImages = exportResult.imageCount;
@@ -314,9 +316,11 @@ class WebDAVService {
 
           // 上传本地备份（无论是否下载，确保远程有最新数据）
           final exportResult = await BackupService.instance.exportDataForAutoBackup();
-          if (exportResult.success && exportResult.zipBytes != null) {
+          if (exportResult.success && exportResult.zipPath != null) {
             final fileName = _generateBackupFileName();
-            final uploadSuccess = await _uploadBytes(client, '$dirUrl/$fileName', username, password, exportResult.zipBytes!);
+            final uploadSuccess = await _uploadFile(client, '$dirUrl/$fileName', username, password, exportResult.zipPath!);
+            // 清理临时 zip 文件
+            try { await File(exportResult.zipPath!).delete(); } catch (_) {}
             if (uploadSuccess) {
               uploadedFiles = 1;
               uploadedImages = exportResult.imageCount;
@@ -361,15 +365,22 @@ class WebDAVService {
     return prefs.getString(_lastSyncKey);
   }
 
-  /// 上传字节数据到 WebDAV
+  /// 上传文件到 WebDAV（从文件路径读取，避免备份服务端重复占用内存）
-  Future<bool> _uploadBytes(
+  Future<bool> _uploadFile(
     http.Client client,
     String url,
     String username,
     String password,
-    Uint8List bytes,
+    String filePath,
   ) async {
     try {
+      final file = File(filePath);
+      if (!await file.exists()) {
+        debugPrint('[WebDAV] _uploadFile: 文件不存在 $filePath');
+        return false;
+      }
+      final bytes = await file.readAsBytes();
+
       var request = http.Request('PUT', Uri.parse(url));
       request.headers['Authorization'] = _basicAuth(username, password);
       request.headers['Content-Type'] = 'application/zip';
@@ -394,7 +405,7 @@ class WebDAVService {
       debugPrint('[WebDAV] PUT $url -> ${response.statusCode}');
       return response.statusCode == 200 || response.statusCode == 201 || response.statusCode == 204;
     } catch (e) {
-      debugPrint('[WebDAV] _uploadBytes error: $e');
+      debugPrint('[WebDAV] _uploadFile error: $e');
       return false;
     }
   }