Rework touch hack to improve startup performance

app/lib/app_init.dart

@@ -40,6 +40,7 @@ import 'package:nc_photos/platform/features.dart' as features;
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/pref_util.dart' as pref_util;
+import 'package:nc_photos/touch_manager.dart';
 import 'package:visibility_detector/visibility_detector.dart';
 
 enum InitIsolateType {
@@ -213,6 +214,7 @@ Future<void> _initDiContainer(InitIsolateType isolateType) async {
   c.tagRepoLocal = TagRepo(TagSqliteDbDataSource(c.sqliteDb));
   c.taggedFileRepo = const TaggedFileRepo(TaggedFileRemoteDataSource());
   c.searchRepo = SearchRepo(SearchSqliteDbDataSource(c));
+  c.touchManager = TouchManager(c);
 
   if (platform_k.isAndroid) {
     // local file currently only supported on Android

app/lib/bloc/scan_account_dir.dart

@@ -1,7 +1,6 @@
 import 'dart:async';
 
 import 'package:bloc/bloc.dart';
-import 'package:collection/collection.dart';
 import 'package:kiwi/kiwi.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
@@ -17,7 +16,6 @@ import 'package:nc_photos/exception_event.dart';
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/throttler.dart';
-import 'package:nc_photos/touch_token_manager.dart';
 import 'package:nc_photos/use_case/ls.dart';
 import 'package:nc_photos/use_case/scan_dir.dart';
 import 'package:nc_photos/use_case/scan_dir_offline.dart';
@@ -135,7 +133,9 @@ class ScanAccountDirBloc
     }));
   }
 
-  static bool require(DiContainer c) => DiContainer.has(c, DiType.fileRepo);
+  static bool require(DiContainer c) =>
+      DiContainer.has(c, DiType.fileRepo) &&
+      DiContainer.has(c, DiType.touchManager);
 
   static ScanAccountDirBloc of(Account account) {
     final name =
@@ -373,98 +373,35 @@ class ScanAccountDirBloc
     // 1st pass: scan for new files
     var files = <File>[];
     final cacheMap = FileForwardCacheManager.prepareFileMap(cache);
-    {
-      final stopwatch = Stopwatch()..start();
-      final fileRepo = FileRepo(FileCachedDataSource(
-        _c,
-        forwardCacheManager: FileForwardCacheManager(_c, cacheMap),
-      ));
-      await for (final event in _queryWithFileRepo(fileRepo, ev,
-          fileRepoForShareDir: _c.fileRepo)) {
-        if (event is ExceptionEvent) {
-          _log.shout("[_queryOnline] Exception while request (1st pass)",
-              event.error, event.stackTrace);
-          emit(ScanAccountDirBlocFailure(
-              cache.isEmpty
-                  ? files
-                  : cache.where((f) => file_util.isSupportedFormat(f)).toList(),
-              event.error));
-          return;
-        }
-        files.addAll(event);
-        if (cache.isEmpty) {
-          // only emit partial results if there's no cache
-          emit(ScanAccountDirBlocLoading(files.toList()));
-        }
-      }
-      _log.info(
-          "[_queryOnline] Elapsed time (pass1): ${stopwatch.elapsedMilliseconds}ms");
-    }
-
-    try {
-      if (_shouldCheckCache) {
-        // 2nd pass: check outdated cache
-        _shouldCheckCache = false;
-
-        // announce the result of the 1st pass
-        // if cache is empty, we have already emitted the results in the loop
-        if (cache.isNotEmpty || files.isEmpty) {
-          // emit results from remote
-          emit(ScanAccountDirBlocLoading(files));
-        }
-
-        // files = await _queryOnlinePass2(ev, cacheMap, files);
-        files = await _queryOnlinePass2(ev, {}, files);
-      }
-    } catch (e, stackTrace) {
-      _log.shout(
-          "[_queryOnline] Failed while _queryOnlinePass2", e, stackTrace);
-    }
-    emit(ScanAccountDirBlocSuccess(files));
-  }
-
-  Future<List<File>> _queryOnlinePass2(ScanAccountDirBlocQueryBase ev,
-      Map<int, File> cacheMap, List<File> pass1Files) async {
-    final touchTokenManager = TouchTokenManager(_c);
-    // combine the file maps because [pass1Files] doesn't contain non-supported
-    // files
-    final pass2CacheMap = CombinedMapView(
-        [FileForwardCacheManager.prepareFileMap(pass1Files), cacheMap]);
+    final stopwatch = Stopwatch()..start();
+    _c.touchManager.clearTouchCache();
     final fileRepo = FileRepo(FileCachedDataSource(
       _c,
+      forwardCacheManager: FileForwardCacheManager(_c, cacheMap),
       shouldCheckCache: true,
-      forwardCacheManager: FileForwardCacheManager(_c, pass2CacheMap),
     ));
-    final remoteTouchEtag = await touchTokenManager.getRemoteRootEtag(account);
-    if (remoteTouchEtag == null) {
-      _log.info("[_queryOnlinePass2] remoteTouchEtag == null");
-      await touchTokenManager.setLocalRootEtag(account, null);
-      return pass1Files;
-    }
-    final localTouchEtag = await touchTokenManager.getLocalRootEtag(account);
-    if (remoteTouchEtag == localTouchEtag) {
-      _log.info("[_queryOnlinePass2] remoteTouchEtag matched");
-      return pass1Files;
-    }
-
-    final stopwatch = Stopwatch()..start();
-    final fileRepoNoCache =
-        FileRepo(FileCachedDataSource(_c, shouldCheckCache: true));
-    final newFiles = <File>[];
-    await for (final event in _queryWithFileRepo(fileRepo, ev,
-        fileRepoForShareDir: fileRepoNoCache)) {
+    await for (final event
+        in _queryWithFileRepo(fileRepo, ev, fileRepoForShareDir: _c.fileRepo)) {
       if (event is ExceptionEvent) {
-        _log.shout("[_queryOnlinePass2] Exception while request (2nd pass)",
-            event.error, event.stackTrace);
-        return pass1Files;
+        _log.shout("[_queryOnline] Exception while request", event.error,
+            event.stackTrace);
+        emit(ScanAccountDirBlocFailure(
+            cache.isEmpty
+                ? files
+                : cache.where((f) => file_util.isSupportedFormat(f)).toList(),
+            event.error));
+        return;
+      }
+      files.addAll(event);
+      if (cache.isEmpty) {
+        // only emit partial results if there's no cache
+        emit(ScanAccountDirBlocLoading(files.toList()));
       }
-      newFiles.addAll(event);
     }
     _log.info(
-        "[_queryOnlinePass2] Elapsed time (pass2): ${stopwatch.elapsedMilliseconds}ms");
-    _log.info("[_queryOnlinePass2] Save new touch root etag: $remoteTouchEtag");
-    await touchTokenManager.setLocalRootEtag(account, remoteTouchEtag);
-    return newFiles;
+        "[_queryOnline] Elapsed time (_queryOnline): ${stopwatch.elapsedMilliseconds}ms, ${files.length} files");
+
+    emit(ScanAccountDirBlocSuccess(files));
   }
 
   /// Emit all files under this account
@@ -560,7 +497,5 @@ class ScanAccountDirBloc
     logTag: "ScanAccountDirBloc.refresh",
   );
 
-  bool _shouldCheckCache = true;
-
   static final _log = Logger("bloc.scan_dir.ScanAccountDirBloc");
 }

app/lib/di_container.dart

@@ -12,6 +12,7 @@ import 'package:nc_photos/entity/tag.dart';
 import 'package:nc_photos/entity/tagged_file.dart';
 import 'package:nc_photos/or_null.dart';
 import 'package:nc_photos/pref.dart';
+import 'package:nc_photos/touch_manager.dart';
 
 enum DiType {
   albumRepo,
@@ -34,6 +35,7 @@ enum DiType {
   searchRepo,
   pref,
   sqliteDb,
+  touchManager,
 }
 
 class DiContainer {
@@ -58,6 +60,7 @@ class DiContainer {
     SearchRepo? searchRepo,
     Pref? pref,
     sql.SqliteDb? sqliteDb,
+    TouchManager? touchManager,
   })  : _albumRepo = albumRepo,
         _albumRepoLocal = albumRepoLocal,
         _faceRepo = faceRepo,
@@ -77,7 +80,8 @@ class DiContainer {
         _localFileRepo = localFileRepo,
         _searchRepo = searchRepo,
         _pref = pref,
-        _sqliteDb = sqliteDb;
+        _sqliteDb = sqliteDb,
+        _touchManager = touchManager;
 
   DiContainer.late();
 
@@ -123,6 +127,8 @@ class DiContainer {
         return contianer._pref != null;
       case DiType.sqliteDb:
         return contianer._sqliteDb != null;
+      case DiType.touchManager:
+        return contianer._touchManager != null;
     }
   }
 
@@ -140,6 +146,7 @@ class DiContainer {
     OrNull<SearchRepo>? searchRepo,
     OrNull<Pref>? pref,
     OrNull<sql.SqliteDb>? sqliteDb,
+    OrNull<TouchManager>? touchManager,
   }) {
     return DiContainer(
       albumRepo: albumRepo == null ? _albumRepo : albumRepo.obj,
@@ -156,6 +163,7 @@ class DiContainer {
       searchRepo: searchRepo == null ? _searchRepo : searchRepo.obj,
       pref: pref == null ? _pref : pref.obj,
       sqliteDb: sqliteDb == null ? _sqliteDb : sqliteDb.obj,
+      touchManager: touchManager == null ? _touchManager : touchManager.obj,
     );
   }
 
@@ -177,6 +185,7 @@ class DiContainer {
   TaggedFileRepo get taggedFileRepo => _taggedFileRepo!;
   LocalFileRepo get localFileRepo => _localFileRepo!;
   SearchRepo get searchRepo => _searchRepo!;
+  TouchManager get touchManager => _touchManager!;
 
   sql.SqliteDb get sqliteDb => _sqliteDb!;
   Pref get pref => _pref!;
@@ -271,6 +280,11 @@ class DiContainer {
     _searchRepo = v;
   }
 
+  set touchManager(TouchManager v) {
+    assert(_touchManager == null);
+    _touchManager = v;
+  }
+
   set sqliteDb(sql.SqliteDb v) {
     assert(_sqliteDb == null);
     _sqliteDb = v;
@@ -302,6 +316,7 @@ class DiContainer {
   TaggedFileRepo? _taggedFileRepo;
   LocalFileRepo? _localFileRepo;
   SearchRepo? _searchRepo;
+  TouchManager? _touchManager;
 
   sql.SqliteDb? _sqliteDb;
   Pref? _pref;

app/lib/entity/file/data_source.dart

@@ -17,11 +17,8 @@ import 'package:nc_photos/exception.dart';
 import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/or_null.dart';
-import 'package:nc_photos/throttler.dart';
-import 'package:nc_photos/touch_token_manager.dart';
 import 'package:nc_photos/use_case/compat/v32.dart';
 import 'package:path/path.dart' as path_lib;
-import 'package:uuid/uuid.dart';
 import 'package:xml/xml.dart';
 
 class FileWebdavDataSource implements FileDataSource {
@@ -583,10 +580,10 @@ class FileCachedDataSource implements FileDataSource {
       await FileSqliteCacheUpdater(_c)(account, dir, remote: remote);
       if (shouldCheckCache) {
         // update our local touch token to match the remote one
-        final tokenManager = TouchTokenManager(_c);
         try {
-          await tokenManager.setLocalToken(
-              account, dir, cacheLoader.remoteTouchToken);
+          _log.info("[list] Update outdated local etag: ${dir.path}");
+          await _c.touchManager
+              .setLocalEtag(account, dir, cacheLoader.remoteTouchEtag);
         } catch (e, stacktrace) {
           _log.shout("[list] Failed while setLocalToken", e, stacktrace);
           // ignore error
@@ -676,19 +673,8 @@ class FileCachedDataSource implements FileDataSource {
     );
 
     // generate a new random token
-    final token = const Uuid().v4().replaceAll("-", "");
     final dir = File(path: path_lib.dirname(f.path));
-    await TouchTokenManager(_c).setLocalToken(account, dir, token);
-    // don't update remote token that frequently
-    (_touchTokenThrottlers["${account.url}/${dir.path}"] ??= Throttler(
-      onTriggered: _updateRemoteTouchToken,
-      logTag: "FileCachedDataSource._touchTokenThrottlers",
-    ))
-        .trigger(
-      maxResponceTime: const Duration(seconds: 20),
-      maxPendingCount: 20,
-      data: _TouchTokenThrottlerData(account, dir, token),
-    );
+    await _c.touchManager.touch(account, dir);
   }
 
   @override
@@ -718,21 +704,8 @@ class FileCachedDataSource implements FileDataSource {
     await _remoteSrc.createDir(account, path);
   }
 
-  Future<void> updateRemoteTouchTokenNow() async {
-    for (final t in _touchTokenThrottlers.values) {
-      await t.triggerNow();
-    }
-  }
-
-  Future<void> _updateRemoteTouchToken(
-      List<_TouchTokenThrottlerData> data) async {
-    try {
-      final d = data.last;
-      await TouchTokenManager(_c).setRemoteToken(d.account, d.dir, d.token);
-    } catch (e, stackTrace) {
-      _log.shout("[_updateRemoteTouchToken] Failed while setRemoteToken", e,
-          stackTrace);
-    }
+  Future<void> flushRemoteTouch() async {
+    return _c.touchManager.flushRemote();
   }
 
   final DiContainer _c;
@@ -742,19 +715,9 @@ class FileCachedDataSource implements FileDataSource {
   final _remoteSrc = const FileWebdavDataSource();
   final FileSqliteDbDataSource _sqliteDbSrc;
 
-  final _touchTokenThrottlers = <String, Throttler<_TouchTokenThrottlerData>>{};
-
   static final _log = Logger("entity.file.data_source.FileCachedDataSource");
 }
 
-class _TouchTokenThrottlerData {
-  const _TouchTokenThrottlerData(this.account, this.dir, this.token);
-
-  final Account account;
-  final File dir;
-  final String token;
-}
-
 /// Forward cache for listing AppDb dirs
 ///
 /// It's very expensive to list a dir and its sub-dirs one by one in multiple

app/lib/entity/file/file_cache_manager.dart

@@ -13,8 +13,6 @@ import 'package:nc_photos/exception.dart';
 import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/list_util.dart' as list_util;
 import 'package:nc_photos/object_extension.dart';
-import 'package:nc_photos/remote_storage_util.dart' as remote_storage_util;
-import 'package:nc_photos/touch_token_manager.dart';
 
 class FileCacheLoader {
   FileCacheLoader(
@@ -51,7 +49,7 @@ class FileCacheLoader {
       }
       if (cacheEtag == remoteEtag) {
         if (shouldCheckCache) {
-          await _checkTouchToken(account, dir, cache);
+          await _checkTouchEtag(account, dir, cache);
         } else {
           _isGood = true;
         }
@@ -67,39 +65,15 @@ class FileCacheLoader {
   }
 
   bool get isGood => _isGood;
-  String? get remoteTouchToken => _remoteToken;
+  String? get remoteTouchEtag => _remoteEtag;
 
-  Future<void> _checkTouchToken(
+  Future<void> _checkTouchEtag(
       Account account, File f, List<File> cache) async {
-    final touchPath =
-        "${remote_storage_util.getRemoteTouchDir(account)}/${f.strippedPath}";
-    final tokenManager = TouchTokenManager(_c);
-    String? remoteToken;
-    try {
-      remoteToken = await tokenManager.getRemoteToken(account, f);
-    } catch (e, stacktrace) {
-      _log.shout(
-          "[_checkTouchToken] Failed getting remote token at '$touchPath'",
-          e,
-          stacktrace);
-    }
-    _remoteToken = remoteToken;
-
-    String? localToken;
-    try {
-      localToken = await tokenManager.getLocalToken(account, f);
-    } catch (e, stacktrace) {
-      _log.shout(
-          "[_checkTouchToken] Failed getting local token at '$touchPath'",
-          e,
-          stacktrace);
-    }
-
-    if (localToken != remoteToken) {
-      _log.info(
-          "[_checkTouchToken] Remote and local token differ, cache outdated");
-    } else {
+    final result = await _c.touchManager.checkTouchEtag(account, f);
+    if (result == null) {
       _isGood = true;
+    } else {
+      _remoteEtag = result;
     }
   }
 
@@ -110,7 +84,7 @@ class FileCacheLoader {
   final FileForwardCacheManager? forwardCacheManager;
 
   var _isGood = false;
-  String? _remoteToken;
+  String? _remoteEtag;
 
   static final _log = Logger("entity.file.file_cache_manager.FileCacheLoader");
 }

app/lib/service.dart

@@ -239,8 +239,7 @@ class _MetadataTask {
 
     final c = KiwiContainer().resolve<DiContainer>();
     if (c.fileRepo.dataSrc is FileCachedDataSource) {
-      await (c.fileRepo.dataSrc as FileCachedDataSource)
-          .updateRemoteTouchTokenNow();
+      await (c.fileRepo.dataSrc as FileCachedDataSource).flushRemoteTouch();
     }
   }
 

app/lib/touch_manager.dart

@@ -0,0 +1,197 @@
+import 'dart:convert';
+
+import 'package:logging/logging.dart';
+import 'package:nc_photos/account.dart';
+import 'package:nc_photos/di_container.dart';
+import 'package:nc_photos/entity/file.dart';
+import 'package:nc_photos/exception.dart';
+import 'package:nc_photos/mobile/platform.dart'
+    if (dart.library.html) 'package:nc_photos/web/platform.dart' as platform;
+import 'package:nc_photos/or_null.dart';
+import 'package:nc_photos/remote_storage_util.dart' as remote_storage_util;
+import 'package:nc_photos/throttler.dart';
+import 'package:nc_photos/use_case/ls_single_file.dart';
+import 'package:nc_photos/use_case/put_file_binary.dart';
+import 'package:path/path.dart' as path_lib;
+import 'package:uuid/uuid.dart';
+
+/// Manage touch events for files
+///
+/// Touch events are used to broadcast file changes that don't trigger an ETag
+/// update to other devices. Such changes include custom properties like
+/// metadata
+class TouchManager {
+  TouchManager(this._c) : assert(require(_c));
+
+  static bool require(DiContainer c) =>
+      DiContainer.has(c, DiType.fileRepo) &&
+      DiContainer.has(c, DiType.fileRepoRemote);
+
+  static String newToken() {
+    return const Uuid().v4().replaceAll("-", "");
+  }
+
+  /// Clear the cached etags
+  ///
+  /// You should call this before a complete re-scan
+  void clearTouchCache() {
+    _log.info("[clearTouchCache]");
+    _resultCache.clear();
+  }
+
+  /// Compare the remote and local etag
+  ///
+  /// Return null if the two etags match, otherwise return the remote etag
+  Future<String?> checkTouchEtag(Account account, File dir) async {
+    if (dir.strippedPathWithEmpty.isNotEmpty) {
+      // check parent
+      if (await checkTouchEtag(
+              account, File(path: path_lib.dirname(dir.path))) ==
+          null) {
+        // parent ok == child ok
+        return null;
+      }
+    }
+    final cacheKey = "${account.url}/${dir.path}";
+    final cache = _resultCache[cacheKey];
+    if (cache != null) {
+      // we checked this dir already, return the cache
+      return cache.obj;
+    }
+
+    String? remoteToken;
+    try {
+      remoteToken = await _getRemoteEtag(account, dir);
+    } catch (e, stacktrace) {
+      _log.shout("[checkTouchEtag] Failed getting remote etag", e, stacktrace);
+    }
+
+    String? localToken;
+    try {
+      localToken = await _getLocalEtag(account, dir);
+    } catch (e, stacktrace) {
+      _log.shout("[checkTouchEtag] Failed getting local etag", e, stacktrace);
+    }
+
+    final isMatch = localToken == remoteToken;
+    final result = OrNull(isMatch ? null : remoteToken);
+    _resultCache[cacheKey] = result;
+    if (!isMatch) {
+      _log.info(
+          "[checkTouchEtag] Remote and local etag differ, cache outdated: ${dir.strippedPath}");
+    } else {
+      _log.info("[checkTouchEtag] etags match: ${dir.strippedPath}");
+    }
+    return result.obj;
+  }
+
+  /// Touch a dir
+  Future<void> touch(Account account, File dir) async {
+    // _log.info("[touch] Touch dir '${dir.path}'");
+    // delete the local etag, we'll update it later. If the app is killed, then
+    // at least the app will update the cache in next run
+    await setLocalEtag(account, dir, null);
+    (_throttlers["${account.url}/${dir.path}"] ??= Throttler(
+      onTriggered: _triggerTouch,
+      logTag: "TouchManager._throttlers",
+    ))
+        .trigger(
+      maxResponceTime: const Duration(seconds: 20),
+      maxPendingCount: 20,
+      data: _ThrottlerData(account, dir),
+    );
+  }
+
+  Future<void> flushRemote() async {
+    for (final t in _throttlers.values) {
+      await t.triggerNow();
+    }
+  }
+
+  Future<void> setLocalEtag(Account account, File dir, String? etag) {
+    final name = _getLocalStorageName(account, dir);
+    if (etag == null) {
+      return platform.UniversalStorage().remove(name);
+    } else {
+      _log.info("[setLocalEtag] Set local etag for file '${dir.path}': $etag");
+      return platform.UniversalStorage().putString(name, etag);
+    }
+  }
+
+  Future<void> _triggerTouch(List<_ThrottlerData> data) async {
+    try {
+      final d = data.last;
+      await _touchRemote(d.account, d.dir);
+      final etag = await _getRemoteEtag(d.account, d.dir);
+      _log.info("[_triggerTouch] Remote etag = $etag");
+      if (etag == null) {
+        _log.severe("[_triggerTouch] etag == null");
+      } else {
+        await setLocalEtag(d.account, d.dir, etag);
+      }
+    } catch (e, stackTrace) {
+      _log.shout("[_triggerTouch] Uncaught exception", e, stackTrace);
+    }
+  }
+
+  /// Update the remote touch dir
+  Future<void> _touchRemote(Account account, File dir) async {
+    _log.info("[touchRemote] Touch remote dir '${dir.path}'");
+    final path = _getRemoteEtagPath(account, dir);
+    return PutFileBinary(_c.fileRepo)(
+        account, "$path/token.txt", const Utf8Encoder().convert(newToken()),
+        shouldCreateMissingDir: true);
+  }
+
+  /// Return the corresponding touch etag for [dir] from remote source, or null
+  /// if no such file
+  Future<String?> _getRemoteEtag(Account account, File dir) async {
+    final path = _getRemoteEtagPath(account, dir);
+    try {
+      final f = await LsSingleFile(_c)(account, path);
+      return f.etag;
+    } on ApiException catch (e) {
+      if (e.response.statusCode == 404) {
+        return null;
+      } else {
+        rethrow;
+      }
+    }
+  }
+
+  String _getRemoteEtagPath(Account account, File dir) {
+    final strippedPath = dir.strippedPath;
+    if (strippedPath == ".") {
+      return remote_storage_util.getRemoteTouchDir(account);
+    } else {
+      return "${remote_storage_util.getRemoteTouchDir(account)}/$strippedPath";
+    }
+  }
+
+  Future<String?> _getLocalEtag(Account account, File file) async {
+    final name = _getLocalStorageName(account, file);
+    return platform.UniversalStorage().getString(name);
+  }
+
+  String _getLocalStorageName(Account account, File file) {
+    final strippedPath = file.strippedPath;
+    if (strippedPath == ".") {
+      return "touch/${account.url.replaceFirst('://', '_')}/${account.userId}/token";
+    } else {
+      return "touch/${account.url.replaceFirst('://', '_')}/${account.userId}/${file.strippedPath}/token";
+    }
+  }
+
+  final DiContainer _c;
+  final _throttlers = <String, Throttler<_ThrottlerData>>{};
+  final _resultCache = <String, OrNull<String>>{};
+
+  static final _log = Logger("touch_token_manager.TouchManager");
+}
+
+class _ThrottlerData {
+  const _ThrottlerData(this.account, this.dir);
+
+  final Account account;
+  final File dir;
+}

app/lib/touch_token_manager.dart

@@ -1,123 +0,0 @@
-import 'dart:convert';
-
-import 'package:logging/logging.dart';
-import 'package:nc_photos/account.dart';
-import 'package:nc_photos/di_container.dart';
-import 'package:nc_photos/entity/file.dart';
-import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/mobile/platform.dart'
-    if (dart.library.html) 'package:nc_photos/web/platform.dart' as platform;
-import 'package:nc_photos/pref.dart';
-import 'package:nc_photos/remote_storage_util.dart' as remote_storage_util;
-import 'package:nc_photos/use_case/get_file_binary.dart';
-import 'package:nc_photos/use_case/ls_single_file.dart';
-import 'package:nc_photos/use_case/put_file_binary.dart';
-import 'package:nc_photos/use_case/remove.dart';
-
-/// Manage touch token for files
-///
-/// Touch tokens are used to broadcast file changes that don't trigger an ETag
-/// update to other devices. Such changes include custom properties like
-/// metadata. In order to detect these hidden changes, you should get both
-/// local and remote tokens and compare them. Beware that getting the remote
-/// token requires downloading a file from the server so you may want to avoid
-/// doing it on every query
-class TouchTokenManager {
-  TouchTokenManager(this._c) : assert(require(_c));
-
-  static bool require(DiContainer c) =>
-      DiContainer.has(c, DiType.fileRepo) &&
-      DiContainer.has(c, DiType.fileRepoRemote);
-
-  Future<String?> getRemoteRootEtag(Account account) async {
-    try {
-      // we use the remote repo here to prevent it caching the result
-      final touchDir = await LsSingleFile(_c.withRemoteFileRepo())(
-          account, remote_storage_util.getRemoteTouchDir(account));
-      return touchDir.etag!;
-    } catch (_) {
-      // dir not found on server
-      return null;
-    }
-  }
-
-  Future<void> setLocalRootEtag(Account account, String? etag) async {
-    if (etag == null) {
-      await AccountPref.of(account).removeTouchRootEtag();
-    } else {
-      await AccountPref.of(account).setTouchRootEtag(etag);
-    }
-  }
-
-  Future<String?> getLocalRootEtag(Account account) async {
-    return AccountPref.of(account).getTouchRootEtag();
-  }
-
-  Future<void> setRemoteToken(Account account, File file, String? token) async {
-    _log.info(
-        "[setRemoteToken] Set remote token for file '${file.path}': $token");
-    final path = _getRemotePath(account, file);
-    if (token == null) {
-      return Remove(_c)(account, [file], shouldCleanUp: false);
-    } else {
-      return PutFileBinary(_c.fileRepo)(
-          account, path, const Utf8Encoder().convert(token),
-          shouldCreateMissingDir: true);
-    }
-  }
-
-  /// Return the touch token for [file] from remote source, or null if no such
-  /// file
-  Future<String?> getRemoteToken(Account account, File file) async {
-    final path = _getRemotePath(account, file);
-    try {
-      final content =
-          await GetFileBinary(_c.fileRepo)(account, File(path: path));
-      return const Utf8Decoder().convert(content);
-    } on ApiException catch (e) {
-      if (e.response.statusCode == 404) {
-        return null;
-      } else {
-        rethrow;
-      }
-    }
-  }
-
-  Future<void> setLocalToken(Account account, File file, String? token) {
-    _log.info(
-        "[setLocalToken] Set local token for file '${file.path}': $token");
-    final name = _getLocalStorageName(account, file);
-    if (token == null) {
-      return platform.UniversalStorage().remove(name);
-    } else {
-      return platform.UniversalStorage().putString(name, token);
-    }
-  }
-
-  Future<String?> getLocalToken(Account account, File file) async {
-    final name = _getLocalStorageName(account, file);
-    return platform.UniversalStorage().getString(name);
-  }
-
-  String _getRemotePath(Account account, File file) {
-    final strippedPath = file.strippedPath;
-    if (strippedPath == ".") {
-      return "${remote_storage_util.getRemoteTouchDir(account)}/token.txt";
-    } else {
-      return "${remote_storage_util.getRemoteTouchDir(account)}/${file.strippedPath}/token.txt";
-    }
-  }
-
-  String _getLocalStorageName(Account account, File file) {
-    final strippedPath = file.strippedPath;
-    if (strippedPath == ".") {
-      return "touch/${account.url.replaceFirst('://', '_')}/${account.userId}/token";
-    } else {
-      return "touch/${account.url.replaceFirst('://', '_')}/${account.userId}/${file.strippedPath}/token";
-    }
-  }
-
-  final DiContainer _c;
-
-  static final _log = Logger("touch_token_manager.TouchTokenManager");
-}