New naming scheme for album files

lib/entity/album.dart

@@ -270,7 +270,7 @@ class AlbumRemoteDataSource implements AlbumDataSource {
     // just make up something
     final timestamp = DateTime.now().millisecondsSinceEpoch;
     final random = Random().nextInt(0xFFFFFF);
-    return "${timestamp.toRadixString(16)}-${random.toRadixString(16).padLeft(6, '0')}.json";
+    return "${timestamp.toRadixString(16)}-${random.toRadixString(16).padLeft(6, '0')}.nc_album.json";
   }
 
   static final _log = Logger("entity.album.AlbumRemoteDataSource");

lib/use_case/compat/v25.dart

@@ -0,0 +1,36 @@
+import 'package:logging/logging.dart';
+import 'package:nc_photos/account.dart';
+import 'package:nc_photos/entity/file.dart';
+import 'package:nc_photos/use_case/move.dart';
+import 'package:path/path.dart' as path;
+
+/// Compatibility helper for v25
+class CompatV25 {
+  /// Return whether the album file need to be migrated to the new naming scheme
+  static bool isAlbumFileNeedMigration(File albumFile) =>
+      albumFile.path.endsWith(".nc_album.json") == false;
+
+  /// Migrate an album file to the new naming scheme
+  static Future<File> migrateAlbumFile(
+          FileRepo fileRepo, Account account, File albumFile) =>
+      _MigrateAlbumFile(fileRepo)(account, albumFile);
+}
+
+class _MigrateAlbumFile {
+  _MigrateAlbumFile(this.fileRepo);
+
+  Future<File> call(Account account, File albumFile) async {
+    assert(CompatV25.isAlbumFileNeedMigration(albumFile));
+    final newPath = path.dirname(albumFile.path) +
+        "/" +
+        path.basenameWithoutExtension(albumFile.path) +
+        ".nc_album.json";
+    _log.info("[call] Migrate album file from '${albumFile.path}' to '$newPath'");
+    await Move(fileRepo)(account, albumFile, newPath);
+    return albumFile.copyWith(path: newPath);
+  }
+
+  final FileRepo fileRepo;
+
+  static final _log = Logger("use_case.compat.v25._MigrateAlbumFile");
+}

lib/use_case/list_album.dart

@@ -5,6 +5,7 @@ import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/exception.dart';
 import 'package:nc_photos/remote_storage_util.dart' as remote_storage_util;
 import 'package:nc_photos/use_case/compat/v15.dart';
+import 'package:nc_photos/use_case/compat/v25.dart';
 import 'package:nc_photos/use_case/ls.dart';
 import 'package:tuple/tuple.dart';
 
@@ -47,8 +48,13 @@ class ListAlbum {
     }
     final albumFiles =
         ls.where((element) => element.isCollection != true).toList();
-    for (final f in albumFiles) {
+    for (var i = 0; i < albumFiles.length; ++i) {
+      var f = albumFiles[i];
       try {
+        if (CompatV25.isAlbumFileNeedMigration(f)) {
+          f = await CompatV25.migrateAlbumFile(fileRepo, account, f);
+        }
+        albumFiles[i] = f;
         yield await albumRepo.get(account, f);
       } catch (e, stacktrace) {
         yield Tuple2(e, stacktrace);