Merge branch 'isolate' into dev

app/lib/app_init.dart

@@ -35,7 +35,12 @@ import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/pref_util.dart' as pref_util;
 
 Future<void> initAppLaunch() async {
-  _initLog();
+  if (_hasInitedInThisIsolate) {
+    _log.warning("[initAppLaunch] Already initialized in this isolate");
+    return;
+  }
+
+  initLog();
   _initKiwi();
   await _initPref();
   await _initAccountPrefs();
@@ -46,9 +51,15 @@ Future<void> initAppLaunch() async {
     _initSelfSignedCertManager();
   }
   _initDiContainer();
+
+  _hasInitedInThisIsolate = true;
+}
+
+void initLog() {
+  if (_hasInitedInThisIsolate) {
+    return;
   }
 
-void _initLog() {
   Logger.root.level = kReleaseMode ? Level.WARNING : Level.ALL;
   Logger.root.onRecord.listen((record) {
     // dev.log(
@@ -162,6 +173,7 @@ void _initDiContainer() {
 }
 
 final _log = Logger("app_init");
+var _hasInitedInThisIsolate = false;
 
 class _BlocObserver extends BlocObserver {
   @override

app/lib/app_localizations.dart

@@ -1,7 +1,24 @@
+import 'package:flutter/widgets.dart';
 import 'package:flutter_gen/gen_l10n/app_localizations.dart';
+import 'package:flutter_gen/gen_l10n/app_localizations_en.dart';
+import 'package:logging/logging.dart';
 import 'package:nc_photos/widget/my_app.dart';
 
 /// Simplify localized string access
 class L10n {
   static AppLocalizations global() => AppLocalizations.of(MyApp.globalContext)!;
+
+  static AppLocalizations of(Locale locale) {
+    try {
+      return lookupAppLocalizations(locale);
+    } on FlutterError catch (_) {
+      // unsupported locale, use default (en)
+      return AppLocalizationsEn();
+    } catch (e, stackTrace) {
+      _log.shout("[of] Failed while lookupAppLocalizations", e, stackTrace);
+      return AppLocalizationsEn();
+    }
+  }
+
+  static final _log = Logger("app_localizations.L10n");
 }

app/lib/compute_queue.dart

@@ -0,0 +1,40 @@
+import 'dart:collection';
+
+import 'package:flutter/foundation.dart';
+
+typedef ComputeQueueCallback<U> = void Function(U result);
+
+/// Compute the jobs in the queue one by one sequentially in isolate
+class ComputeQueue<T, U> {
+  void addJob(T event, ComputeCallback<T, U> callback,
+      ComputeQueueCallback<U> onResult) {
+    _queue.addLast(_Job(event, callback, onResult));
+    if (_queue.length == 1) {
+      _startProcessing();
+    }
+  }
+
+  bool get isProcessing => _queue.isNotEmpty;
+
+  Future<void> _startProcessing() async {
+    while (_queue.isNotEmpty) {
+      final ev = _queue.first;
+      try {
+        final result = await compute(ev.callback, ev.message);
+        ev.onResult(result);
+      } finally {
+        _queue.removeFirst();
+      }
+    }
+  }
+
+  final _queue = Queue<_Job<T, U>>();
+}
+
+class _Job<T, U> {
+  const _Job(this.message, this.callback, this.onResult);
+
+  final T message;
+  final ComputeCallback<T, U> callback;
+  final ComputeQueueCallback<U> onResult;
+}

app/lib/entity/file/data_source.dart

@@ -13,12 +13,12 @@ import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/webdav_response_parser.dart';
 import 'package:nc_photos/exception.dart';
 import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/or_null.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:tuple/tuple.dart';
 import 'package:uuid/uuid.dart';
 import 'package:xml/xml.dart';
 
@@ -64,7 +64,7 @@ class FileWebdavDataSource implements FileDataSource {
     }
 
     final xml = XmlDocument.parse(response.body);
-    var files = WebdavResponseParser().parseFiles(xml);
+    var files = await WebdavResponseParser().parseFiles(xml);
     // _log.fine("[list] Parsed files: [$files]");
     bool hasNoMediaMarker = false;
     files = files
@@ -269,9 +269,9 @@ class FileAppDbDataSource implements FileDataSource {
   const FileAppDbDataSource(this.appDb);
 
   @override
-  list(Account account, File dir) {
+  list(Account account, File dir) async {
     _log.info("[list] ${dir.path}");
-    return appDb.use(
+    final dbItems = await appDb.use(
       (db) => db.transaction(
           [AppDb.dirStoreName, AppDb.file2StoreName], idbModeReadOnly),
       (transaction) async {
@@ -284,21 +284,31 @@ class FileAppDbDataSource implements FileDataSource {
         }
         final dirEntry =
             AppDbDirEntry.fromJson(dirItem.cast<String, dynamic>());
-        final entries = await dirEntry.children.mapStream((c) async {
+        return Tuple2(
+          dirEntry.dir,
+          await Future.wait(
+            dirEntry.children.map((c) async {
               final fileItem = await fileStore
                   .getObject(AppDbFile2Entry.toPrimaryKey(account, c)) as Map?;
               if (fileItem == null) {
                 _log.warning(
                     "[list] Missing file ($c) in db for dir: ${logFilename(dir.path)}");
                 throw CacheNotFoundException("No entry for dir child: $c");
+              } else {
+                return fileItem;
               }
-          return AppDbFile2Entry.fromJson(fileItem.cast<String, dynamic>());
+            }),
-        }, k.simultaneousQuery).toList();
+            eagerError: true,
-        // we need to add dir to match the remote query
+          ),
-        return [dirEntry.dir] +
+        );
-            entries.map((e) => e.file).where((f) => _validateFile(f)).toList();
       },
     );
+    // we need to add dir to match the remote query
+    return [
+      dbItems.item1,
+      ...(await dbItems.item2.computeAll(_covertAppDbFile2Entry))
+          .where((f) => _validateFile(f))
+    ];
   }
 
   @override
@@ -647,20 +657,16 @@ class FileForwardCacheManager {
 
     // query other files
     if (needQuery.isNotEmpty) {
-      final fileItems = await appDb.use(
+      final dbItems = await appDb.use(
         (db) => db.transaction(AppDb.file2StoreName, idbModeReadOnly),
         (transaction) async {
           final store = transaction.objectStore(AppDb.file2StoreName);
-          return await needQuery
+          return await Future.wait(needQuery.map((id) =>
-              .mapStream(
+              store.getObject(AppDbFile2Entry.toPrimaryKey(account, id))));
-                  (id) => store
-                      .getObject(AppDbFile2Entry.toPrimaryKey(account, id)),
-                  k.simultaneousQuery)
-              .toList();
         },
       );
-      files.addAll(fileItems.cast<Map?>().whereType<Map>().map(
+      files.addAll(
-          (i) => AppDbFile2Entry.fromJson(i.cast<String, dynamic>()).file));
+          await dbItems.whereType<Map>().computeAll(_covertAppDbFile2Entry));
     }
     _fileCache.addEntries(files.map((f) => MapEntry(f.fileId!, f)));
     _log.info(
@@ -692,3 +698,6 @@ bool _validateFile(File f) {
   // See: https://gitlab.com/nkming2/nc-photos/-/issues/9
   return f.lastModified != null;
 }
+
+File _covertAppDbFile2Entry(Map json) =>
+    AppDbFile2Entry.fromJson(json.cast<String, dynamic>()).file;

app/lib/entity/local_file.dart

@@ -9,6 +9,9 @@ abstract class LocalFile with EquatableMixin {
   /// careful that this does NOT mean that the two objects are identical
   bool compareIdentity(LocalFile other);
 
+  /// hashCode to be used with [compareIdentity]
+  int get identityHashCode;
+
   String get logTag;
 
   String get filename;
@@ -41,6 +44,9 @@ class LocalUriFile with EquatableMixin implements LocalFile {
     }
   }
 
+  @override
+  get identityHashCode => uri.hashCode;
+
   @override
   toString() {
     var product = "$runtimeType {"

app/lib/entity/webdav_response_parser.dart

@@ -1,7 +1,9 @@
 import 'dart:convert';
 import 'dart:io';
 
+import 'package:flutter/foundation.dart';
 import 'package:logging/logging.dart';
+import 'package:nc_photos/app_init.dart' as app_init;
 import 'package:nc_photos/ci_string.dart';
 import 'package:nc_photos/entity/favorite.dart';
 import 'package:nc_photos/entity/file.dart';
@@ -11,18 +13,30 @@ import 'package:nc_photos/string_extension.dart';
 import 'package:xml/xml.dart';
 
 class WebdavResponseParser {
-  List<File> parseFiles(XmlDocument xml) => _parse<File>(xml, _toFile);
+  Future<List<File>> parseFiles(XmlDocument xml) =>
+      compute(_parseFilesIsolate, xml);
 
-  List<Favorite> parseFavorites(XmlDocument xml) =>
+  Future<List<Favorite>> parseFavorites(XmlDocument xml) =>
-      _parse<Favorite>(xml, _toFavorite);
+      compute(_parseFavoritesIsolate, xml);
 
-  List<Tag> parseTags(XmlDocument xml) => _parse<Tag>(xml, _toTag);
+  Future<List<Tag>> parseTags(XmlDocument xml) =>
+      compute(_parseTagsIsolate, xml);
 
-  List<TaggedFile> parseTaggedFiles(XmlDocument xml) =>
+  Future<List<TaggedFile>> parseTaggedFiles(XmlDocument xml) =>
-      _parse<TaggedFile>(xml, _toTaggedFile);
+      compute(_parseTaggedFilesIsolate, xml);
 
   Map<String, String> get namespaces => _namespaces;
 
+  List<File> _parseFiles(XmlDocument xml) => _parse<File>(xml, _toFile);
+
+  List<Favorite> _parseFavorites(XmlDocument xml) =>
+      _parse<Favorite>(xml, _toFavorite);
+
+  List<Tag> _parseTags(XmlDocument xml) => _parse<Tag>(xml, _toTag);
+
+  List<TaggedFile> _parseTaggedFiles(XmlDocument xml) =>
+      _parse<TaggedFile>(xml, _toTaggedFile);
+
   List<T> _parse<T>(XmlDocument xml, T? Function(XmlElement) mapper) {
     _namespaces = _parseNamespaces(xml);
     final body = () {
@@ -501,3 +515,23 @@ extension on XmlElement {
                 .any((element) => element.key == name.prefix));
   }
 }
+
+List<File> _parseFilesIsolate(XmlDocument xml) {
+  app_init.initLog();
+  return WebdavResponseParser()._parseFiles(xml);
+}
+
+List<Favorite> _parseFavoritesIsolate(XmlDocument xml) {
+  app_init.initLog();
+  return WebdavResponseParser()._parseFavorites(xml);
+}
+
+List<Tag> _parseTagsIsolate(XmlDocument xml) {
+  app_init.initLog();
+  return WebdavResponseParser()._parseTags(xml);
+}
+
+List<TaggedFile> _parseTaggedFilesIsolate(XmlDocument xml) {
+  app_init.initLog();
+  return WebdavResponseParser()._parseTaggedFiles(xml);
+}

app/lib/iterable_extension.dart

@@ -1,6 +1,7 @@
 import 'dart:async';
 
 import 'package:flutter/foundation.dart';
+import 'package:nc_photos/list_extension.dart';
 import 'package:nc_photos/override_comparator.dart';
 import 'package:tuple/tuple.dart';
 
@@ -23,56 +24,6 @@ extension IterableExtension<T> on Iterable<T> {
     }
   }
 
-  /// The current elements of this iterable modified by async function [fn].
-  ///
-  /// The result of [fn] will be emitted by the returned stream in the same
-  /// order as this iterable.
-  ///
-  /// If [simultaneousFuture] > 1, [fn] will be called multiple times before
-  /// awaiting their results.
-  Stream<U> mapStream<U>(
-    Future<U> Function(T element) fn, [
-    simultaneousFuture = 1,
-  ]) async* {
-    final container = <Future<U>>[];
-    for (final e in this) {
-      container.add(fn(e));
-      if (container.length >= simultaneousFuture) {
-        for (final result in await Future.wait(container)) {
-          yield result;
-        }
-        container.clear();
-      }
-    }
-    if (container.isNotEmpty) {
-      for (final result in await Future.wait(container)) {
-        yield result;
-      }
-    }
-  }
-
-  /// Invokes async function [fn] on each element of this iterable in iteration
-  /// order.
-  ///
-  /// If [simultaneousFuture] > 1, [fn] will be called multiple times before
-  /// awaiting their results.
-  Future<void> forEachAsync(
-    Future Function(T element) fn, [
-    simultaneousFuture = 1,
-  ]) async {
-    final container = <Future>[];
-    for (final e in this) {
-      container.add(fn(e));
-      if (container.length >= simultaneousFuture) {
-        await Future.wait(container);
-        container.clear();
-      }
-    }
-    if (container.isNotEmpty) {
-      await Future.wait(container);
-    }
-  }
-
   Iterable<Tuple2<int, T>> withIndex() => mapWithIndex((i, e) => Tuple2(i, e));
 
   /// Whether the collection contains an element equal to [element] using the
@@ -114,4 +65,34 @@ extension IterableExtension<T> on Iterable<T> {
       yield e;
     }
   }
+
+  Future<List<U>> computeAll<U>(ComputeCallback<T, U> callback) async {
+    return await compute(
+        _computeAllImpl<T, U>, _ComputeAllMessage(callback, asList()));
+  }
+
+  /// Return a list containing elements in this iterable
+  ///
+  /// If this Iterable is itself a list, this will be returned directly with no
+  /// copying
+  List<T> asList() {
+    if (this is List) {
+      return this as List<T>;
+    } else {
+      return toList();
+    }
+  }
+}
+
+class _ComputeAllMessage<T, U> {
+  const _ComputeAllMessage(this.callback, this.data);
+
+  final ComputeCallback<T, U> callback;
+  final List<T> data;
+}
+
+Future<List<U>> _computeAllImpl<T, U>(_ComputeAllMessage<T, U> message) async {
+  final result = await Future.wait(
+      message.data.map((e) async => await message.callback(e)));
+  return result;
 }

app/lib/k.dart

@@ -36,6 +36,3 @@ const coverSize = 512;
 
 /// AppDb lock ID
 const appDbLockId = 1;
-
-/// Number of async query task that can be called simultaneously
-const simultaneousQuery = 20;

app/lib/object_extension.dart

@@ -20,4 +20,7 @@ extension ObjectExtension<T> on T {
   Future<U> runFuture<U>(FutureOr<U> Function(T obj) fn) async {
     return await fn(this);
   }
+
+  /// Cast this as U, or null if this is not an object of U
+  U? as<U>() => this is U ? this as U : null;
 }

app/lib/use_case/find_file.dart

@@ -1,11 +1,9 @@
+import 'package:flutter/foundation.dart';
 import 'package:idb_shim/idb_client.dart';
 import 'package:nc_photos/account.dart';
 import 'package:nc_photos/app_db.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file.dart';
-import 'package:nc_photos/iterable_extension.dart';
-import 'package:nc_photos/k.dart' as k;
-import 'package:quiver/iterables.dart';
 
 class FindFile {
   FindFile(this._c) : assert(require(_c));
@@ -25,27 +23,22 @@ class FindFile {
       (db) => db.transaction(AppDb.file2StoreName, idbModeReadOnly),
       (transaction) async {
         final fileStore = transaction.objectStore(AppDb.file2StoreName);
-        return await fileIds
+        return await Future.wait(fileIds.map((id) =>
-            .mapStream(
+            fileStore.getObject(AppDbFile2Entry.toPrimaryKey(account, id))));
-                (id) => fileStore
-                    .getObject(AppDbFile2Entry.toPrimaryKey(account, id)),
-                k.simultaneousQuery)
-            .toList();
       },
     );
+    final fileMap = await compute(_covertFileMap, dbItems);
     final files = <File>[];
-    for (final pair in zip([fileIds, dbItems])) {
+    for (final id in fileIds) {
-      final dbItem = pair[1] as Map?;
+      final f = fileMap[id];
-      if (dbItem == null) {
+      if (f == null) {
         if (onFileNotFound == null) {
-          throw StateError("File ID not found: ${pair[0]}");
+          throw StateError("File ID not found: $id");
         } else {
-          onFileNotFound(pair[0] as int);
+          onFileNotFound(id);
         }
       } else {
-        final dbEntry =
+        files.add(f);
-            AppDbFile2Entry.fromJson(dbItem.cast<String, dynamic>());
-        files.add(dbEntry.file);
       }
     }
     return files;
@@ -53,3 +46,10 @@ class FindFile {
 
   final DiContainer _c;
 }
+
+Map<int, File> _covertFileMap(List<Object?> dbItems) {
+  return Map.fromEntries(dbItems
+      .whereType<Map>()
+      .map((j) => AppDbFile2Entry.fromJson(j.cast<String, dynamic>()).file)
+      .map((f) => MapEntry(f.fileId!, f)));
+}

app/lib/use_case/resync_album.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/foundation.dart';
 import 'package:idb_shim/idb_client.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
@@ -6,8 +7,7 @@ import 'package:nc_photos/debug_util.dart';
 import 'package:nc_photos/entity/album.dart';
 import 'package:nc_photos/entity/album/item.dart';
 import 'package:nc_photos/entity/album/provider.dart';
-import 'package:nc_photos/iterable_extension.dart';
+import 'package:nc_photos/entity/file.dart';
-import 'package:nc_photos/k.dart' as k;
 
 /// Resync files inside an album with the file db
 class ResyncAlbum {
@@ -20,31 +20,21 @@ class ResyncAlbum {
           "Resync only make sense for static albums: ${album.name}");
     }
     final items = AlbumStaticProvider.of(album).items;
-    final fileIds =
+    final dbItems = await appDb.use(
-        items.whereType<AlbumFileItem>().map((i) => i.file.fileId!).toList();
-    final dbItems = Map.fromEntries(await appDb.use(
       (db) => db.transaction(AppDb.file2StoreName, idbModeReadOnly),
       (transaction) async {
         final store = transaction.objectStore(AppDb.file2StoreName);
-        return await fileIds
+        return await Future.wait(items.whereType<AlbumFileItem>().map((i) =>
-            .mapStream(
+            store.getObject(
-                (id) async => MapEntry(
+                AppDbFile2Entry.toPrimaryKey(account, i.file.fileId!))));
-                      id,
-                      await store.getObject(
-                          AppDbFile2Entry.toPrimaryKey(account, id)) as Map?,
-                    ),
-                k.simultaneousQuery)
-            .toList();
       },
-    ));
+    );
+    final fileMap = await compute(_covertFileMap, dbItems);
     return items.map((i) {
       if (i is AlbumFileItem) {
         try {
-          final dbItem = dbItems[i.file.fileId]!;
-          final dbEntry =
-              AppDbFile2Entry.fromJson(dbItem.cast<String, dynamic>());
           return i.copyWith(
-            file: dbEntry.file,
+            file: fileMap[i.file.fileId]!,
           );
         } catch (e, stackTrace) {
           _log.shout(
@@ -63,3 +53,10 @@ class ResyncAlbum {
 
   static final _log = Logger("use_case.resync_album.ResyncAlbum");
 }
+
+Map<int, File> _covertFileMap(List<Object?> dbItems) {
+  return Map.fromEntries(dbItems
+      .whereType<Map>()
+      .map((j) => AppDbFile2Entry.fromJson(j.cast<String, dynamic>()).file)
+      .map((f) => MapEntry(f.fileId!, f)));
+}

app/lib/use_case/scan_dir_offline.dart

@@ -4,6 +4,7 @@ import 'package:nc_photos/app_db.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
+import 'package:nc_photos/iterable_extension.dart';
 
 class ScanDirOffline {
   ScanDirOffline(this._c) : assert(require(_c));
@@ -11,12 +12,12 @@ class ScanDirOffline {
   static bool require(DiContainer c) => DiContainer.has(c, DiType.appDb);
 
   /// List all files under a dir recursively from the local DB
-  Future<List<File>> call(
+  Future<Iterable<File>> call(
     Account account,
     File root, {
     bool isOnlySupportedFormat = true,
   }) async {
-    return await _c.appDb.use(
+    final dbItems = await _c.appDb.use(
       (db) => db.transaction(AppDb.file2StoreName, idbModeReadOnly),
       (transaction) async {
         final store = transaction.objectStore(AppDb.file2StoreName);
@@ -25,20 +26,25 @@ class ScanDirOffline {
           AppDbFile2Entry.toStrippedPathIndexLowerKeyForDir(account, root),
           AppDbFile2Entry.toStrippedPathIndexUpperKeyForDir(account, root),
         );
-        final product = <File>[];
+        return await index
-        await for (final c
+            .openCursor(range: range, autoAdvance: false)
-            in index.openCursor(range: range, autoAdvance: false)) {
+            .map((c) {
-          final e = AppDbFile2Entry.fromJson(
+          final v = c.value as Map;
-              (c.value as Map).cast<String, dynamic>());
-          if (!isOnlySupportedFormat || file_util.isSupportedFormat(e.file)) {
-            product.add(e.file);
-          }
           c.next();
-        }
+          return v;
-        return product;
+        }).toList();
       },
     );
+    final results = await dbItems.computeAll(_covertAppDbFile2Entry);
+    if (isOnlySupportedFormat) {
+      return results.where((f) => file_util.isSupportedFormat(f));
+    } else {
+      return results;
+    }
   }
 
   final DiContainer _c;
 }
+
+File _covertAppDbFile2Entry(Map json) =>
+    AppDbFile2Entry.fromJson(json.cast<String, dynamic>()).file;

app/lib/widget/album_browser.dart

@@ -18,6 +18,7 @@ import 'package:nc_photos/event/event.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/list_extension.dart';
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/or_null.dart';
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/session_storage.dart';
@@ -117,6 +118,11 @@ class _AlbumBrowserState extends State<AlbumBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<_ListItem>()?.onTap?.call();
+  }
+
   @override
   @protected
   get canEdit => _album?.albumFile?.isOwned(widget.account.username) == true;
@@ -888,19 +894,18 @@ enum _SelectionMenuOption {
 abstract class _ListItem implements SelectableItem, DraggableItem {
   const _ListItem({
     required this.index,
-    VoidCallback? onTap,
+    this.onTap,
     DragTargetAccept<DraggableItem>? onDropBefore,
     DragTargetAccept<DraggableItem>? onDropAfter,
     VoidCallback? onDragStarted,
     VoidCallback? onDragEndedAny,
-  })  : _onTap = onTap,
+  })  : _onDropBefore = onDropBefore,
-        _onDropBefore = onDropBefore,
         _onDropAfter = onDropAfter,
         _onDragStarted = onDragStarted,
         _onDragEndedAny = onDragEndedAny;
 
   @override
-  get onTap => _onTap;
+  get isTappable => onTap != null;
 
   @override
   get isSelectable => true;
@@ -935,7 +940,7 @@ abstract class _ListItem implements SelectableItem, DraggableItem {
 
   final int index;
 
-  final VoidCallback? _onTap;
+  final VoidCallback? onTap;
   final DragTargetAccept<DraggableItem>? _onDropBefore;
   final DragTargetAccept<DraggableItem>? _onDropAfter;
   final VoidCallback? _onDragStarted;

app/lib/widget/archive_browser.dart

@@ -1,23 +1,25 @@
+import 'dart:ui';
+
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
-import 'package:nc_photos/api/api_util.dart' as api_util;
 import 'package:nc_photos/app_db.dart';
 import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/bloc/scan_account_dir.dart';
+import 'package:nc_photos/compute_queue.dart';
 import 'package:nc_photos/debug_util.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file/data_source.dart';
-import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/language_util.dart' as language_util;
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/theme.dart';
 import 'package:nc_photos/use_case/update_property.dart';
+import 'package:nc_photos/widget/builder/photo_list_item_builder.dart';
 import 'package:nc_photos/widget/empty_list_indicator.dart';
 import 'package:nc_photos/widget/photo_list_item.dart';
 import 'package:nc_photos/widget/photo_list_util.dart' as photo_list_util;
@@ -81,6 +83,18 @@ class _ArchiveBrowserState extends State<ArchiveBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<PhotoListFileItem>()?.run((fileItem) {
+      Navigator.pushNamed(
+        context,
+        Viewer.routeName,
+        arguments:
+            ViewerArguments(widget.account, _backingFiles, fileItem.fileIndex),
+      );
+    });
+  }
+
   void _initBloc() {
     if (_bloc.state is ScanAccountDirBlocInit) {
       _log.info("[_initBloc] Initialize bloc");
@@ -96,7 +110,9 @@ class _ArchiveBrowserState extends State<ArchiveBrowser>
   }
 
   Widget _buildContent(BuildContext context, ScanAccountDirBlocState state) {
-    if (state is ScanAccountDirBlocSuccess && itemStreamListItems.isEmpty) {
+    if (state is ScanAccountDirBlocSuccess &&
+        !_buildItemQueue.isProcessing &&
+        itemStreamListItems.isEmpty) {
       return Column(
         children: [
           AppBar(
@@ -132,7 +148,8 @@ class _ArchiveBrowserState extends State<ArchiveBrowser>
               ),
             ),
           ),
-          if (state is ScanAccountDirBlocLoading)
+          if (state is ScanAccountDirBlocLoading ||
+              _buildItemQueue.isProcessing)
             const Align(
               alignment: Alignment.bottomCenter,
               child: LinearProgressIndicator(),
@@ -207,11 +224,6 @@ class _ArchiveBrowserState extends State<ArchiveBrowser>
     }
   }
 
-  void _onItemTap(int index) {
-    Navigator.pushNamed(context, Viewer.routeName,
-        arguments: ViewerArguments(widget.account, _backingFiles, index));
-  }
-
   Future<void> _onSelectionAppBarUnarchivePressed() async {
     SnackBarManager().showSnackBar(SnackBar(
       content: Text(L10n.global()
@@ -219,7 +231,7 @@ class _ArchiveBrowserState extends State<ArchiveBrowser>
       duration: k.snackBarDurationShort,
     ));
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -254,37 +266,25 @@ class _ArchiveBrowserState extends State<ArchiveBrowser>
   }
 
   void _transformItems(List<File> files) {
-    _backingFiles = files
+    _buildItemQueue.addJob(
-        .where((f) => f.isArchived == true)
+      PhotoListItemBuilderArguments(
-        .sorted(compareFileDateTimeDescending);
+        widget.account,
-
+        files,
-    itemStreamListItems = () sync* {
+        isArchived: true,
-      for (int i = 0; i < _backingFiles.length; ++i) {
+        sorter: photoListFileDateTimeSorter,
-        final f = _backingFiles[i];
+        locale: language_util.getSelectedLocale() ??
-
+            PlatformDispatcher.instance.locale,
-        final previewUrl = api_util.getFilePreviewUrl(widget.account, f,
+      ),
-            width: k.photoThumbSize, height: k.photoThumbSize);
+      buildPhotoListItem,
-        if (file_util.isSupportedImageFormat(f)) {
+      (result) {
-          yield _ImageListItem(
+        if (mounted) {
-            file: f,
+          setState(() {
-            account: widget.account,
+            _backingFiles = result.backingFiles;
-            previewUrl: previewUrl,
+            itemStreamListItems = result.listItems;
-            onTap: () => _onItemTap(i),
+          });
-          );
-        } else if (file_util.isSupportedVideoFormat(f)) {
-          yield _VideoListItem(
-            file: f,
-            account: widget.account,
-            previewUrl: previewUrl,
-            onTap: () => _onItemTap(i),
-          );
-        } else {
-          _log.shout(
-              "[_transformItems] Unsupported file format: ${f.contentType}");
         }
-      }
+      },
-    }()
+    );
-        .toList();
   }
 
   void _reqQuery() {
@@ -295,83 +295,11 @@ class _ArchiveBrowserState extends State<ArchiveBrowser>
 
   var _backingFiles = <File>[];
 
+  final _buildItemQueue =
+      ComputeQueue<PhotoListItemBuilderArguments, PhotoListItemBuilderResult>();
+
   var _thumbZoomLevel = 0;
   int get _thumbSize => photo_list_util.getThumbSize(_thumbZoomLevel);
 
   static final _log = Logger("widget.archive_browser._ArchiveBrowserState");
 }
-
-abstract class _ListItem implements SelectableItem {
-  _ListItem({
-    VoidCallback? onTap,
-  }) : _onTap = onTap;
-
-  @override
-  get onTap => _onTap;
-
-  @override
-  get isSelectable => true;
-
-  @override
-  get staggeredTile => const StaggeredTile.count(1, 1);
-
-  final VoidCallback? _onTap;
-}
-
-abstract class _FileListItem extends _ListItem {
-  _FileListItem({
-    required this.file,
-    VoidCallback? onTap,
-  }) : super(onTap: onTap);
-
-  @override
-  operator ==(Object other) {
-    return other is _FileListItem && file.path == other.file.path;
-  }
-
-  @override
-  get hashCode => file.path.hashCode;
-
-  final File file;
-}
-
-class _ImageListItem extends _FileListItem {
-  _ImageListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListImage(
-      account: account,
-      previewUrl: previewUrl,
-      isGif: file.contentType == "image/gif",
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}
-
-class _VideoListItem extends _FileListItem {
-  _VideoListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListVideo(
-      account: account,
-      previewUrl: previewUrl,
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}

app/lib/widget/builder/photo_list_item_builder.dart

@@ -0,0 +1,183 @@
+import 'package:collection/collection.dart' show compareNatural;
+import 'package:flutter/widgets.dart';
+import 'package:logging/logging.dart';
+import 'package:nc_photos/account.dart';
+import 'package:nc_photos/api/api_util.dart' as api_util;
+import 'package:nc_photos/app_init.dart' as app_init;
+import 'package:nc_photos/app_localizations.dart';
+import 'package:nc_photos/entity/album.dart';
+import 'package:nc_photos/entity/file.dart';
+import 'package:nc_photos/entity/file_util.dart' as file_util;
+import 'package:nc_photos/iterable_extension.dart';
+import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/object_extension.dart';
+import 'package:nc_photos/widget/photo_list_item.dart';
+import 'package:nc_photos/widget/photo_list_util.dart';
+import 'package:nc_photos/widget/selectable_item_stream_list_mixin.dart';
+
+class PhotoListItemBuilderArguments {
+  const PhotoListItemBuilderArguments(
+    this.account,
+    this.files, {
+    this.isArchived = false,
+    required this.sorter,
+    this.grouper,
+    this.shouldBuildSmartAlbums = false,
+    this.shouldShowFavoriteBadge = false,
+    required this.locale,
+  });
+
+  final Account account;
+  final List<File> files;
+  final bool isArchived;
+  final PhotoListItemSorter? sorter;
+  final PhotoListItemGrouper? grouper;
+  final bool shouldBuildSmartAlbums;
+  final bool shouldShowFavoriteBadge;
+
+  /// Locale is needed to get localized string
+  final Locale locale;
+}
+
+class PhotoListItemBuilderResult {
+  const PhotoListItemBuilderResult(
+    this.backingFiles,
+    this.listItems, {
+    this.smartAlbums = const [],
+  });
+
+  final List<File> backingFiles;
+  final List<SelectableItem> listItems;
+  final List<Album> smartAlbums;
+}
+
+typedef PhotoListItemSorter = int Function(File, File);
+
+abstract class PhotoListItemGrouper {
+  const PhotoListItemGrouper();
+
+  SelectableItem? onFile(File file);
+}
+
+class PhotoListFileDateGrouper implements PhotoListItemGrouper {
+  PhotoListFileDateGrouper({
+    required this.isMonthOnly,
+  }) : helper = DateGroupHelper(isMonthOnly: isMonthOnly);
+
+  @override
+  onFile(File file) => helper
+      .onFile(file)
+      ?.run((date) => PhotoListDateItem(date: date, isMonthOnly: isMonthOnly));
+
+  final bool isMonthOnly;
+  final DateGroupHelper helper;
+}
+
+int photoListFileDateTimeSorter(File a, File b) =>
+    compareFileDateTimeDescending(a, b);
+
+int photoListFilenameSorter(File a, File b) =>
+    compareNatural(b.filename, a.filename);
+
+PhotoListItemBuilderResult buildPhotoListItem(
+    PhotoListItemBuilderArguments arg) {
+  app_init.initLog();
+  return _PhotoListItemBuilder(
+    isArchived: arg.isArchived,
+    sorter: arg.sorter,
+    grouper: arg.grouper,
+    shouldBuildSmartAlbums: arg.shouldBuildSmartAlbums,
+    shouldShowFavoriteBadge: arg.shouldShowFavoriteBadge,
+    locale: arg.locale,
+  )(arg.account, arg.files);
+}
+
+class _PhotoListItemBuilder {
+  const _PhotoListItemBuilder({
+    required this.isArchived,
+    required this.sorter,
+    required this.grouper,
+    required this.shouldBuildSmartAlbums,
+    required this.shouldShowFavoriteBadge,
+    required this.locale,
+  });
+
+  PhotoListItemBuilderResult call(Account account, List<File> files) {
+    final s = Stopwatch()..start();
+    try {
+      return _fromSortedItems(account, _sortItems(files));
+    } finally {
+      _log.info("[call] Elapsed time: ${s.elapsedMilliseconds}ms");
+    }
+  }
+
+  List<File> _sortItems(List<File> files) {
+    final filtered = files.where((f) => (f.isArchived ?? false) == isArchived);
+    if (sorter == null) {
+      return filtered.toList();
+    } else {
+      return filtered.stableSorted(sorter);
+    }
+  }
+
+  PhotoListItemBuilderResult _fromSortedItems(
+      Account account, List<File> files) {
+    final today = DateTime.now();
+    final memoryAlbumHelper =
+        shouldBuildSmartAlbums ? MemoryAlbumHelper(today) : null;
+    final listItems = <SelectableItem>[];
+    for (int i = 0; i < files.length; ++i) {
+      final f = files[i];
+      grouper?.onFile(f)?.run((item) => listItems.add(item));
+      memoryAlbumHelper?.addFile(f);
+
+      final item = _buildListItem(i, account, f);
+      if (item != null) {
+        listItems.add(item);
+      }
+    }
+    final smartAlbums = memoryAlbumHelper
+        ?.build((year) => L10n.of(locale).memoryAlbumName(today.year - year));
+    return PhotoListItemBuilderResult(
+      files,
+      listItems,
+      smartAlbums: smartAlbums ?? [],
+    );
+  }
+
+  SelectableItem? _buildListItem(int i, Account account, File file) {
+    final previewUrl = api_util.getFilePreviewUrl(account, file,
+        width: k.photoThumbSize, height: k.photoThumbSize);
+    if (file_util.isSupportedImageFormat(file)) {
+      return PhotoListImageItem(
+        fileIndex: i,
+        file: file,
+        account: account,
+        previewUrl: previewUrl,
+        shouldShowFavoriteBadge: shouldShowFavoriteBadge,
+      );
+    } else if (file_util.isSupportedVideoFormat(file)) {
+      return PhotoListVideoItem(
+        fileIndex: i,
+        file: file,
+        account: account,
+        previewUrl: previewUrl,
+        shouldShowFavoriteBadge: shouldShowFavoriteBadge,
+      );
+    } else {
+      _log.shout(
+          "[_buildListItem] Unsupported file format: ${file.contentType}");
+      return null;
+    }
+  }
+
+  final bool isArchived;
+  final PhotoListItemSorter? sorter;
+  final PhotoListItemGrouper? grouper;
+  final bool shouldBuildSmartAlbums;
+  final bool shouldShowFavoriteBadge;
+  final Locale locale;
+
+  static final _log =
+      Logger("widget.builder.photo_list_item_builder._PhotoListItemBuilder");
+}

app/lib/widget/dynamic_album_browser.dart

@@ -20,6 +20,7 @@ import 'package:nc_photos/event/event.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
 import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/or_null.dart';
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/share_handler.dart';
@@ -111,6 +112,11 @@ class _DynamicAlbumBrowserState extends State<DynamicAlbumBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<_ListItem>()?.onTap?.call();
+  }
+
   @override
   @protected
   get canEdit => _album?.albumFile?.isOwned(widget.account.username) == true;
@@ -654,11 +660,11 @@ enum _SelectionMenuOption {
 abstract class _ListItem implements SelectableItem {
   const _ListItem({
     required this.index,
-    VoidCallback? onTap,
+    this.onTap,
-  }) : _onTap = onTap;
+  });
 
   @override
-  get onTap => _onTap;
+  get isTappable => onTap != null;
 
   @override
   get isSelectable => true;
@@ -675,7 +681,7 @@ abstract class _ListItem implements SelectableItem {
 
   final int index;
 
-  final VoidCallback? _onTap;
+  final VoidCallback? onTap;
 }
 
 abstract class _FileListItem extends _ListItem {

app/lib/widget/enhanced_photo_browser.dart

@@ -1,17 +1,18 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:logging/logging.dart';
+import 'package:nc_photos/app_init.dart' as app_init;
 import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/bloc/scan_local_dir.dart';
+import 'package:nc_photos/compute_queue.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/entity/local_file.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
 import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
 import 'package:nc_photos/mobile/android/android_info.dart';
-import 'package:nc_photos/mobile/android/content_uri_image_provider.dart';
 import 'package:nc_photos/mobile/android/permission_util.dart';
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/share_handler.dart';
@@ -20,6 +21,7 @@ import 'package:nc_photos/theme.dart';
 import 'package:nc_photos/widget/empty_list_indicator.dart';
 import 'package:nc_photos/widget/handler/delete_local_selection_handler.dart';
 import 'package:nc_photos/widget/local_file_viewer.dart';
+import 'package:nc_photos/widget/photo_list_item.dart';
 import 'package:nc_photos/widget/photo_list_util.dart' as photo_list_util;
 import 'package:nc_photos/widget/selectable_item_stream_list_mixin.dart';
 import 'package:nc_photos/widget/selection_app_bar.dart';
@@ -91,6 +93,17 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<PhotoListLocalFileItem>()?.run((fileItem) {
+      Navigator.pushNamed(
+        context,
+        LocalFileViewer.routeName,
+        arguments: LocalFileViewerArguments(_backingFiles, fileItem.fileIndex),
+      );
+    });
+  }
+
   void _initBloc() {
     if (_bloc.state is ScanLocalDirBlocInit) {
       _log.info("[_initBloc] Initialize bloc");
@@ -123,6 +136,7 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
         ],
       );
     } else if (state is ScanLocalDirBlocSuccess &&
+        !_buildItemQueue.isProcessing &&
         itemStreamListItems.isEmpty) {
       return Column(
         children: [
@@ -159,7 +173,7 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
               ),
             ),
           ),
-          if (state is ScanLocalDirBlocLoading)
+          if (state is ScanLocalDirBlocLoading || _buildItemQueue.isProcessing)
             const Align(
               alignment: Alignment.bottomCenter,
               child: LinearProgressIndicator(),
@@ -237,7 +251,7 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
 
   Future<void> _onSelectionSharePressed(BuildContext context) async {
     final selected = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListLocalFileItem>()
         .map((e) => e.file)
         .toList();
     await ShareHandler(
@@ -285,7 +299,7 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
     }
 
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListLocalFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -294,30 +308,18 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
     await const DeleteLocalSelectionHandler()(selectedFiles: selectedFiles);
   }
 
-  void _onItemTap(int index) {
-    Navigator.pushNamed(context, LocalFileViewer.routeName,
-        arguments: LocalFileViewerArguments(_backingFiles, index));
-  }
-
   void _transformItems(List<LocalFile> files) {
-    // we use last modified here to keep newly enhanced photo at the top
+    _buildItemQueue.addJob(
-    _backingFiles =
+      _BuilderArguments(files),
-        files.stableSorted((a, b) => b.lastModified.compareTo(a.lastModified));
+      _buildPhotoListItem,
-
+      (result) {
-    itemStreamListItems = () sync* {
+        setState(() {
-      for (int i = 0; i < _backingFiles.length; ++i) {
+          _backingFiles = result.backingFiles;
-        final f = _backingFiles[i];
+          itemStreamListItems = result.listItems;
-        if (file_util.isSupportedImageMime(f.mime ?? "")) {
+        });
-          yield _ImageListItem(
+      },
-            file: f,
-            onTap: () => _onItemTap(i),
     );
   }
-      }
-    }()
-        .toList();
-    _log.info("[_transformItems] Length: ${itemStreamListItems.length}");
-  }
 
   void _openInitialImage(String filename) {
     final index = _backingFiles.indexWhere((f) => f.filename == filename);
@@ -361,6 +363,8 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
 
   var _backingFiles = <LocalFile>[];
 
+  final _buildItemQueue = ComputeQueue<_BuilderArguments, _BuilderResult>();
+
   var _isFirstRun = true;
   var _thumbZoomLevel = 0;
   int get _thumbSize => photo_list_util.getThumbSize(_thumbZoomLevel);
@@ -370,76 +374,67 @@ class _EnhancedPhotoBrowserState extends State<EnhancedPhotoBrowser>
       Logger("widget.enhanced_photo_browser._EnhancedPhotoBrowserState");
 }
 
-abstract class _ListItem implements SelectableItem {
-  _ListItem({
-    VoidCallback? onTap,
-  }) : _onTap = onTap;
-
-  @override
-  get onTap => _onTap;
-
-  @override
-  get isSelectable => true;
-
-  @override
-  get staggeredTile => const StaggeredTile.count(1, 1);
-
-  final VoidCallback? _onTap;
-}
-
-abstract class _FileListItem extends _ListItem {
-  _FileListItem({
-    required this.file,
-    VoidCallback? onTap,
-  }) : super(onTap: onTap);
-
-  final LocalFile file;
-}
-
-class _ImageListItem extends _FileListItem {
-  _ImageListItem({
-    required LocalFile file,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    final ImageProvider provider;
-    if (file is LocalUriFile) {
-      provider = ContentUriImage((file as LocalUriFile).uri);
-    } else {
-      throw ArgumentError("Invalid file");
-    }
-
-    return Padding(
-      padding: const EdgeInsets.all(2),
-      child: FittedBox(
-        clipBehavior: Clip.hardEdge,
-        fit: BoxFit.cover,
-        child: Container(
-          // arbitrary size here
-          constraints: BoxConstraints.tight(const Size(128, 128)),
-          color: AppTheme.getListItemBackgroundColor(context),
-          child: Image(
-            image: ResizeImage.resizeIfNeeded(k.photoThumbSize, null, provider),
-            filterQuality: FilterQuality.high,
-            fit: BoxFit.cover,
-            errorBuilder: (context, e, stackTrace) {
-              return Center(
-                child: Icon(
-                  Icons.image_not_supported,
-                  size: 64,
-                  color: Colors.white.withOpacity(.8),
-                ),
-              );
-            },
-          ),
-        ),
-      ),
-    );
-  }
-}
-
 enum _SelectionMenuOption {
   delete,
 }
+
+class _BuilderResult {
+  const _BuilderResult(this.backingFiles, this.listItems);
+
+  final List<LocalFile> backingFiles;
+  final List<SelectableItem> listItems;
+}
+
+class _BuilderArguments {
+  const _BuilderArguments(this.files);
+
+  final List<LocalFile> files;
+}
+
+class _Builder {
+  _BuilderResult call(List<LocalFile> files) {
+    final s = Stopwatch()..start();
+    try {
+      return _fromSortedItems(_sortItems(files));
+    } finally {
+      _log.info("[call] Elapsed time: ${s.elapsedMilliseconds}ms");
+    }
+  }
+
+  List<LocalFile> _sortItems(List<LocalFile> files) {
+    // we use last modified here to keep newly enhanced photo at the top
+    return files
+        .stableSorted((a, b) => b.lastModified.compareTo(a.lastModified));
+  }
+
+  _BuilderResult _fromSortedItems(List<LocalFile> files) {
+    final listItems = <SelectableItem>[];
+    for (int i = 0; i < files.length; ++i) {
+      final f = files[i];
+      final item = _buildListItem(i, f);
+      if (item != null) {
+        listItems.add(item);
+      }
+    }
+    return _BuilderResult(files, listItems);
+  }
+
+  SelectableItem? _buildListItem(int i, LocalFile file) {
+    if (file_util.isSupportedImageMime(file.mime ?? "")) {
+      return PhotoListLocalImageItem(
+        fileIndex: i,
+        file: file,
+      );
+    } else {
+      _log.shout("[_buildListItem] Unsupported file format: ${file.mime}");
+      return null;
+    }
+  }
+
+  static final _log = Logger("widget.enhanced_photo_browser._Builder");
+}
+
+_BuilderResult _buildPhotoListItem(_BuilderArguments arg) {
+  app_init.initLog();
+  return _Builder()(arg.files);
+}

app/lib/widget/favorite_browser.dart

@@ -1,23 +1,25 @@
+import 'dart:ui';
+
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:kiwi/kiwi.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
-import 'package:nc_photos/api/api_util.dart' as api_util;
 import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/bloc/list_favorite.dart';
+import 'package:nc_photos/compute_queue.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/download_handler.dart';
 import 'package:nc_photos/entity/file.dart';
-import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/language_util.dart' as language_util;
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/share_handler.dart';
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/theme.dart';
+import 'package:nc_photos/widget/builder/photo_list_item_builder.dart';
 import 'package:nc_photos/widget/empty_list_indicator.dart';
 import 'package:nc_photos/widget/handler/add_selection_to_album_handler.dart';
 import 'package:nc_photos/widget/handler/archive_selection_handler.dart';
@@ -84,6 +86,18 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<PhotoListFileItem>()?.run((fileItem) {
+      Navigator.pushNamed(
+        context,
+        Viewer.routeName,
+        arguments:
+            ViewerArguments(widget.account, _backingFiles, fileItem.fileIndex),
+      );
+    });
+  }
+
   void _initBloc() {
     if (_bloc.state is ListFavoriteBlocInit) {
       _log.info("[_initBloc] Initialize bloc");
@@ -99,7 +113,9 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
   }
 
   Widget _buildContent(BuildContext context, ListFavoriteBlocState state) {
-    if (state is ListFavoriteBlocSuccess && itemStreamListItems.isEmpty) {
+    if (state is ListFavoriteBlocSuccess &&
+        !_buildItemQueue.isProcessing &&
+        itemStreamListItems.isEmpty) {
       return Column(
         children: [
           AppBar(
@@ -142,7 +158,7 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
               ),
             ),
           ),
-          if (state is ListFavoriteBlocLoading)
+          if (state is ListFavoriteBlocLoading || _buildItemQueue.isProcessing)
             const Align(
               alignment: Alignment.bottomCenter,
               child: LinearProgressIndicator(),
@@ -211,9 +227,7 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
           minZoom: -1,
           maxZoom: 2,
           onZoomChanged: (value) {
-            setState(() {
             _setThumbZoomLevel(value.round());
-            });
             Pref().setHomePhotosZoomLevel(_thumbZoomLevel);
           },
         ),
@@ -236,11 +250,6 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
     }
   }
 
-  void _onItemTap(int index) {
-    Navigator.pushNamed(context, Viewer.routeName,
-        arguments: ViewerArguments(widget.account, _backingFiles, index));
-  }
-
   void _onRefreshSelected() {
     _reqRefresh();
   }
@@ -265,7 +274,7 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
 
   void _onSelectionSharePressed(BuildContext context) {
     final selected = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     ShareHandler(
@@ -283,7 +292,7 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
       context: context,
       account: widget.account,
       selectedFiles: selectedListItems
-          .whereType<_FileListItem>()
+          .whereType<PhotoListFileItem>()
           .map((e) => e.file)
           .toList(),
       clearSelection: () {
@@ -298,7 +307,7 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
 
   void _onSelectionDownloadPressed() {
     final selected = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     DownloadHandler().downloadFiles(widget.account, selected);
@@ -309,7 +318,7 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
 
   Future<void> _onSelectionArchivePressed(BuildContext context) async {
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -323,7 +332,7 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
 
   Future<void> _onSelectionDeletePressed(BuildContext context) async {
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -336,46 +345,26 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
     );
   }
 
-  void _transformItems(List<File> files) {
+  void _transformItems(List<File> files, {bool isSorted = false}) {
-    _backingFiles = files
+    _buildItemQueue.addJob(
-        .where((f) => f.isArchived != true)
+      PhotoListItemBuilderArguments(
-        .sorted(compareFileDateTimeDescending);
+        widget.account,
-
+        files,
-    final isMonthOnly = _thumbZoomLevel < 0;
+        sorter: isSorted ? null : photoListFileDateTimeSorter,
-    final dateHelper = photo_list_util.DateGroupHelper(
+        grouper: PhotoListFileDateGrouper(isMonthOnly: _thumbZoomLevel < 0),
-      isMonthOnly: isMonthOnly,
+        locale: language_util.getSelectedLocale() ??
-    );
+            PlatformDispatcher.instance.locale,
-    itemStreamListItems = () sync* {
+      ),
-      for (int i = 0; i < _backingFiles.length; ++i) {
+      buildPhotoListItem,
-        final f = _backingFiles[i];
+      (result) {
-        final date = dateHelper.onFile(f);
+        if (mounted) {
-        if (date != null) {
+          setState(() {
-          yield _DateListItem(date: date, isMonthOnly: isMonthOnly);
+            _backingFiles = result.backingFiles;
+            itemStreamListItems = result.listItems;
+          });
         }
-
+      },
-        final previewUrl = api_util.getFilePreviewUrl(widget.account, f,
-            width: k.photoThumbSize, height: k.photoThumbSize);
-        if (file_util.isSupportedImageFormat(f)) {
-          yield _ImageListItem(
-            file: f,
-            account: widget.account,
-            previewUrl: previewUrl,
-            onTap: () => _onItemTap(i),
     );
-        } else if (file_util.isSupportedVideoFormat(f)) {
-          yield _VideoListItem(
-            file: f,
-            account: widget.account,
-            previewUrl: previewUrl,
-            onTap: () => _onItemTap(i),
-          );
-        } else {
-          _log.shout(
-              "[_transformItems] Unsupported file format: ${f.contentType}");
-        }
-      }
-    }()
-        .toList();
   }
 
   void _reqQuery() {
@@ -397,9 +386,13 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
 
   void _setThumbZoomLevel(int level) {
     final prevLevel = _thumbZoomLevel;
-    _thumbZoomLevel = level;
     if ((prevLevel >= 0) != (level >= 0)) {
-      _transformItems(_backingFiles);
+      _thumbZoomLevel = level;
+      _transformItems(_backingFiles, isSorted: true);
+    } else {
+      setState(() {
+        _thumbZoomLevel = level;
+      });
     }
   }
 
@@ -407,111 +400,15 @@ class _FavoriteBrowserState extends State<FavoriteBrowser>
 
   var _backingFiles = <File>[];
 
+  final _buildItemQueue =
+      ComputeQueue<PhotoListItemBuilderArguments, PhotoListItemBuilderResult>();
+
   var _thumbZoomLevel = 0;
   int get _thumbSize => photo_list_util.getThumbSize(_thumbZoomLevel);
 
   static final _log = Logger("widget.archive_browser._FavoriteBrowserState");
 }
 
-abstract class _ListItem implements SelectableItem {
-  _ListItem({
-    VoidCallback? onTap,
-  }) : _onTap = onTap;
-
-  @override
-  get onTap => _onTap;
-
-  @override
-  get isSelectable => true;
-
-  @override
-  get staggeredTile => const StaggeredTile.count(1, 1);
-
-  final VoidCallback? _onTap;
-}
-
-class _DateListItem extends _ListItem {
-  _DateListItem({
-    required this.date,
-    this.isMonthOnly = false,
-  });
-
-  @override
-  get isSelectable => false;
-
-  @override
-  get staggeredTile => const StaggeredTile.extent(99, 32);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListDate(
-      date: date,
-      isMonthOnly: isMonthOnly,
-    );
-  }
-
-  final DateTime date;
-  final bool isMonthOnly;
-}
-
-abstract class _FileListItem extends _ListItem {
-  _FileListItem({
-    required this.file,
-    VoidCallback? onTap,
-  }) : super(onTap: onTap);
-
-  @override
-  operator ==(Object other) {
-    return other is _FileListItem && file.path == other.file.path;
-  }
-
-  @override
-  get hashCode => file.path.hashCode;
-
-  final File file;
-}
-
-class _ImageListItem extends _FileListItem {
-  _ImageListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListImage(
-      account: account,
-      previewUrl: previewUrl,
-      isGif: file.contentType == "image/gif",
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}
-
-class _VideoListItem extends _FileListItem {
-  _VideoListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListVideo(
-      account: account,
-      previewUrl: previewUrl,
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}
-
 enum _SelectionMenuOption {
   archive,
   delete,

app/lib/widget/home_albums.dart

@@ -16,6 +16,7 @@ import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/event/event.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/platform/features.dart' as features;
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/snack_bar_manager.dart';
@@ -82,6 +83,11 @@ class _HomeAlbumsState extends State<HomeAlbums>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<_ListItem>()?.onTap?.call();
+  }
+
   void _initBloc() {
     if (_bloc.state is ListAlbumBlocInit) {
       _log.info("[_initBloc] Initialize bloc");
@@ -547,6 +553,8 @@ abstract class _ListItem implements SelectableItem {
   }) : _myOnTap = onTap;
 
   @override
+  get isTappable => _myOnTap != null;
+
   get onTap => _myOnTap;
 
   @override

app/lib/widget/home_photos.dart

@@ -1,11 +1,9 @@
 import 'dart:math' as math;
 import 'dart:ui';
 
-import 'package:collection/collection.dart' show compareNatural;
 import 'package:draggable_scrollbar/draggable_scrollbar.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:kiwi/kiwi.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
@@ -13,6 +11,7 @@ import 'package:nc_photos/api/api_util.dart' as api_util;
 import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/bloc/bloc_util.dart' as bloc_util;
 import 'package:nc_photos/bloc/scan_account_dir.dart';
+import 'package:nc_photos/compute_queue.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/download_handler.dart';
 import 'package:nc_photos/entity/album.dart';
@@ -21,9 +20,10 @@ import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/event/event.dart';
 import 'package:nc_photos/exception.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/language_util.dart' as language_util;
 import 'package:nc_photos/metadata_task_manager.dart';
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/platform/k.dart' as platform_k;
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/primitive.dart';
@@ -33,6 +33,7 @@ import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/theme.dart';
 import 'package:nc_photos/use_case/sync_favorite.dart';
 import 'package:nc_photos/widget/album_browser_util.dart' as album_browser_util;
+import 'package:nc_photos/widget/builder/photo_list_item_builder.dart';
 import 'package:nc_photos/widget/handler/add_selection_to_album_handler.dart';
 import 'package:nc_photos/widget/handler/archive_selection_handler.dart';
 import 'package:nc_photos/widget/handler/remove_selection_handler.dart';
@@ -92,6 +93,18 @@ class _HomePhotosState extends State<HomePhotos>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<PhotoListFileItem>()?.run((fileItem) {
+      Navigator.pushNamed(
+        context,
+        Viewer.routeName,
+        arguments:
+            ViewerArguments(widget.account, _backingFiles, fileItem.fileIndex),
+      );
+    });
+  }
+
   void _initBloc() {
     if (_bloc.state is ScanAccountDirBlocInit) {
       _log.info("[_initBloc] Initialize bloc");
@@ -168,7 +181,8 @@ class _HomePhotosState extends State<HomePhotos>
             child: Column(
               mainAxisSize: MainAxisSize.min,
               children: [
-                if (state is ScanAccountDirBlocLoading)
+                if (state is ScanAccountDirBlocLoading ||
+                    _buildItemQueue.isProcessing)
                   const LinearProgressIndicator(),
                 SizedBox(
                   width: double.infinity,
@@ -254,9 +268,7 @@ class _HomePhotosState extends State<HomePhotos>
           minZoom: -1,
           maxZoom: 2,
           onZoomChanged: (value) {
-            setState(() {
             _setThumbZoomLevel(value.round());
-            });
             Pref().setHomePhotosZoomLevel(_thumbZoomLevel);
           },
         ),
@@ -329,11 +341,6 @@ class _HomePhotosState extends State<HomePhotos>
     }
   }
 
-  void _onItemTap(int index) {
-    Navigator.pushNamed(context, Viewer.routeName,
-        arguments: ViewerArguments(widget.account, _backingFiles, index));
-  }
-
   void _onRefreshSelected() {
     _hasFiredMetadataTask.value = false;
     _reqRefresh();
@@ -359,7 +366,7 @@ class _HomePhotosState extends State<HomePhotos>
 
   void _onSelectionSharePressed(BuildContext context) {
     final selected = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     ShareHandler(
@@ -377,7 +384,7 @@ class _HomePhotosState extends State<HomePhotos>
       context: context,
       account: widget.account,
       selectedFiles: selectedListItems
-          .whereType<_FileListItem>()
+          .whereType<PhotoListFileItem>()
           .map((e) => e.file)
           .toList(),
       clearSelection: () {
@@ -392,7 +399,7 @@ class _HomePhotosState extends State<HomePhotos>
 
   void _onSelectionDownloadPressed() {
     final selected = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     DownloadHandler().downloadFiles(widget.account, selected);
@@ -403,7 +410,7 @@ class _HomePhotosState extends State<HomePhotos>
 
   Future<void> _onSelectionArchivePressed(BuildContext context) async {
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -417,7 +424,7 @@ class _HomePhotosState extends State<HomePhotos>
 
   Future<void> _onSelectionDeletePressed(BuildContext context) async {
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -440,9 +447,7 @@ class _HomePhotosState extends State<HomePhotos>
     } else if (ev.key == PrefKey.isPhotosTabSortByName) {
       if (_bloc.state is! ScanAccountDirBlocInit) {
         _log.info("[_onPrefUpdated] Update view after changing sort option");
-        setState(() {
         _transformItems(_bloc.state.files);
-        });
       }
     }
   }
@@ -491,83 +496,40 @@ class _HomePhotosState extends State<HomePhotos>
   }
 
   /// Transform a File list to grid items
-  void _transformItems(List<File> files) {
+  void _transformItems(List<File> files, {bool isSorted = false}) {
-    if (!Pref().isPhotosTabSortByNameOr()) {
+    _log.info("[_transformItems] Queue ${files.length} items");
-      _transformItemsByDate(files);
+    final PhotoListItemSorter? sorter;
+    final PhotoListItemGrouper? grouper;
+    if (Pref().isPhotosTabSortByNameOr()) {
+      sorter = isSorted ? null : photoListFilenameSorter;
+      grouper = null;
     } else {
-      _transformItemsByName(files);
+      sorter = isSorted ? null : photoListFileDateTimeSorter;
-    }
+      grouper = PhotoListFileDateGrouper(isMonthOnly: _thumbZoomLevel < 0);
     }
 
-  void _transformItemsByName(List<File> files) {
+    _buildItemQueue.addJob(
-    _backingFiles = files
+      PhotoListItemBuilderArguments(
-        .where((f) => f.isArchived != true)
+        widget.account,
-        .sorted((a, b) => compareNatural(b.filename, a.filename));
+        files,
-
+        sorter: sorter,
-    itemStreamListItems = () sync* {
+        grouper: grouper,
-      for (int i = 0; i < _backingFiles.length; ++i) {
+        shouldBuildSmartAlbums: true,
-        final item = _transformItemToListItem(i, _backingFiles[i]);
+        shouldShowFavoriteBadge: true,
-        if (item != null) {
+        locale: language_util.getSelectedLocale() ??
-          yield item;
+            PlatformDispatcher.instance.locale,
+      ),
+      buildPhotoListItem,
+      (result) {
+        if (mounted) {
+          setState(() {
+            _backingFiles = result.backingFiles;
+            itemStreamListItems = result.listItems;
+            _smartAlbums = result.smartAlbums;
+          });
         }
-      }
+      },
-    }()
-        .toList();
-  }
-
-  void _transformItemsByDate(List<File> files) {
-    _backingFiles = files
-        .where((f) => f.isArchived != true)
-        .sorted(compareFileDateTimeDescending);
-
-    final isMonthOnly = _thumbZoomLevel < 0;
-    final dateHelper = photo_list_util.DateGroupHelper(
-      isMonthOnly: isMonthOnly,
     );
-    final today = DateTime.now();
-    final memoryAlbumHelper = photo_list_util.MemoryAlbumHelper(today);
-    itemStreamListItems = () sync* {
-      for (int i = 0; i < _backingFiles.length; ++i) {
-        final f = _backingFiles[i];
-        final date = dateHelper.onFile(f);
-        if (date != null) {
-          yield _DateListItem(date: date, isMonthOnly: isMonthOnly);
-        }
-        memoryAlbumHelper.addFile(f);
-
-        final item = _transformItemToListItem(i, f);
-        if (item != null) {
-          yield item;
-        }
-      }
-    }()
-        .toList();
-    _smartAlbums = memoryAlbumHelper
-        .build((year) => L10n.global().memoryAlbumName(today.year - year));
-  }
-
-  _ListItem? _transformItemToListItem(int i, File f) {
-    final previewUrl = api_util.getFilePreviewUrl(widget.account, f,
-        width: k.photoThumbSize, height: k.photoThumbSize);
-    if (file_util.isSupportedImageFormat(f)) {
-      return _ImageListItem(
-        file: f,
-        account: widget.account,
-        previewUrl: previewUrl,
-        onTap: () => _onItemTap(i),
-      );
-    } else if (file_util.isSupportedVideoFormat(f)) {
-      return _VideoListItem(
-        file: f,
-        account: widget.account,
-        previewUrl: previewUrl,
-        onTap: () => _onItemTap(i),
-      );
-    } else {
-      _log.shout(
-          "[_transformItemToListItem] Unsupported file format: ${f.contentType}");
-      return null;
-    }
   }
 
   void _reqQuery() {
@@ -589,9 +551,13 @@ class _HomePhotosState extends State<HomePhotos>
 
   void _setThumbZoomLevel(int level) {
     final prevLevel = _thumbZoomLevel;
-    _thumbZoomLevel = level;
     if ((prevLevel >= 0) != (level >= 0)) {
-      _transformItems(_backingFiles);
+      _thumbZoomLevel = level;
+      _transformItems(_backingFiles, isSorted: true);
+    } else {
+      setState(() {
+        _thumbZoomLevel = level;
+      });
     }
   }
 
@@ -664,6 +630,9 @@ class _HomePhotosState extends State<HomePhotos>
   var _backingFiles = <File>[];
   var _smartAlbums = <Album>[];
 
+  final _buildItemQueue =
+      ComputeQueue<PhotoListItemBuilderArguments, PhotoListItemBuilderResult>();
+
   var _thumbZoomLevel = 0;
   int get _thumbSize => photo_list_util.getThumbSize(_thumbZoomLevel);
 
@@ -854,107 +823,6 @@ class _Web {
   static const _metadataTaskHeaderHeight = 32.0;
 }
 
-abstract class _ListItem implements SelectableItem {
-  _ListItem({
-    VoidCallback? onTap,
-  }) : _onTap = onTap;
-
-  @override
-  get onTap => _onTap;
-
-  @override
-  get isSelectable => true;
-
-  @override
-  get staggeredTile => const StaggeredTile.count(1, 1);
-
-  final VoidCallback? _onTap;
-}
-
-class _DateListItem extends _ListItem {
-  _DateListItem({
-    required this.date,
-    this.isMonthOnly = false,
-  });
-
-  @override
-  get isSelectable => false;
-
-  @override
-  get staggeredTile => const StaggeredTile.extent(99, 32);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListDate(
-      date: date,
-      isMonthOnly: isMonthOnly,
-    );
-  }
-
-  final DateTime date;
-  final bool isMonthOnly;
-}
-
-abstract class _FileListItem extends _ListItem {
-  _FileListItem({
-    required this.file,
-    VoidCallback? onTap,
-  }) : super(onTap: onTap);
-
-  @override
-  operator ==(Object other) {
-    return other is _FileListItem && file.path == other.file.path;
-  }
-
-  @override
-  get hashCode => file.path.hashCode;
-
-  final File file;
-}
-
-class _ImageListItem extends _FileListItem {
-  _ImageListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListImage(
-      account: account,
-      previewUrl: previewUrl,
-      isGif: file.contentType == "image/gif",
-      isFavorite: file.isFavorite == true,
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}
-
-class _VideoListItem extends _FileListItem {
-  _VideoListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListVideo(
-      account: account,
-      previewUrl: previewUrl,
-      isFavorite: file.isFavorite == true,
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}
-
 class _MetadataTaskHeaderDelegate extends SliverPersistentHeaderDelegate {
   const _MetadataTaskHeaderDelegate({
     required this.extent,

app/lib/widget/person_browser.dart

@@ -22,6 +22,7 @@ import 'package:nc_photos/event/event.dart';
 import 'package:nc_photos/exception_util.dart' as exception_util;
 import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/share_handler.dart';
 import 'package:nc_photos/snack_bar_manager.dart';
@@ -106,6 +107,11 @@ class _PersonBrowserState extends State<PersonBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<_ListItem>()?.onTap?.call();
+  }
+
   void _initBloc() {
     _log.info("[_initBloc] Initialize bloc");
     _reqQuery();
@@ -463,11 +469,11 @@ class _ListItem implements SelectableItem {
     required this.file,
     required this.account,
     required this.previewUrl,
-    VoidCallback? onTap,
+    this.onTap,
-  }) : _onTap = onTap;
+  });
 
   @override
-  get onTap => _onTap;
+  get isTappable => onTap != null;
 
   @override
   get isSelectable => true;
@@ -503,7 +509,7 @@ class _ListItem implements SelectableItem {
   final File file;
   final Account account;
   final String previewUrl;
-  final VoidCallback? _onTap;
+  final VoidCallback? onTap;
 }
 
 enum _SelectionMenuOption {

app/lib/widget/photo_list_item.dart

@@ -1,12 +1,194 @@
 import 'package:cached_network_image/cached_network_image.dart';
 import 'package:cached_network_image_platform_interface/cached_network_image_platform_interface.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:intl/intl.dart';
 import 'package:nc_photos/account.dart';
 import 'package:nc_photos/api/api.dart';
 import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/cache_manager_util.dart';
+import 'package:nc_photos/entity/file.dart';
+import 'package:nc_photos/entity/local_file.dart';
+import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/mobile/android/content_uri_image_provider.dart';
 import 'package:nc_photos/theme.dart';
+import 'package:nc_photos/widget/selectable_item_stream_list_mixin.dart';
+
+abstract class PhotoListFileItem extends SelectableItem {
+  const PhotoListFileItem({
+    required this.fileIndex,
+    required this.file,
+    required this.shouldShowFavoriteBadge,
+  });
+
+  @override
+  get isTappable => true;
+
+  @override
+  get isSelectable => true;
+
+  @override
+  operator ==(Object other) =>
+      other is PhotoListFileItem && file.compareServerIdentity(other.file);
+
+  @override
+  get hashCode => file.path.hashCode;
+
+  @override
+  toString() => "$runtimeType {"
+        "fileIndex: $fileIndex, "
+        "file: ${file.path}, "
+        "shouldShowFavoriteBadge: $shouldShowFavoriteBadge, "
+        "}";
+
+  final int fileIndex;
+  final File file;
+  final bool shouldShowFavoriteBadge;
+}
+
+class PhotoListImageItem extends PhotoListFileItem {
+  const PhotoListImageItem({
+    required int fileIndex,
+    required File file,
+    required this.account,
+    required this.previewUrl,
+    required bool shouldShowFavoriteBadge,
+  }) : super(
+          fileIndex: fileIndex,
+          file: file,
+          shouldShowFavoriteBadge: shouldShowFavoriteBadge,
+        );
+
+  @override
+  buildWidget(BuildContext context) => PhotoListImage(
+        account: account,
+        previewUrl: previewUrl,
+        isGif: file.contentType == "image/gif",
+        isFavorite: shouldShowFavoriteBadge && file.isFavorite == true,
+      );
+
+  final Account account;
+  final String previewUrl;
+}
+
+class PhotoListVideoItem extends PhotoListFileItem {
+  const PhotoListVideoItem({
+    required int fileIndex,
+    required File file,
+    required this.account,
+    required this.previewUrl,
+    required bool shouldShowFavoriteBadge,
+  }) : super(
+          fileIndex: fileIndex,
+          file: file,
+          shouldShowFavoriteBadge: shouldShowFavoriteBadge,
+        );
+
+  @override
+  buildWidget(BuildContext context) => PhotoListVideo(
+        account: account,
+        previewUrl: previewUrl,
+        isFavorite: shouldShowFavoriteBadge && file.isFavorite == true,
+      );
+
+  final Account account;
+  final String previewUrl;
+}
+
+class PhotoListDateItem extends SelectableItem {
+  const PhotoListDateItem({
+    required this.date,
+    this.isMonthOnly = false,
+  });
+
+  @override
+  get isTappable => false;
+
+  @override
+  get isSelectable => false;
+
+  @override
+  get staggeredTile => const StaggeredTile.extent(99, 32);
+
+  @override
+  buildWidget(BuildContext context) => PhotoListDate(
+        date: date,
+        isMonthOnly: isMonthOnly,
+      );
+
+  final DateTime date;
+  final bool isMonthOnly;
+}
+
+abstract class PhotoListLocalFileItem extends SelectableItem {
+  const PhotoListLocalFileItem({
+    required this.fileIndex,
+    required this.file,
+  });
+
+  @override
+  get isTappable => true;
+
+  @override
+  get isSelectable => true;
+
+  @override
+  operator ==(Object other) =>
+      other is PhotoListLocalFileItem && file.compareIdentity(other.file);
+
+  @override
+  get hashCode => file.identityHashCode;
+
+  final int fileIndex;
+  final LocalFile file;
+}
+
+class PhotoListLocalImageItem extends PhotoListLocalFileItem {
+  const PhotoListLocalImageItem({
+    required int fileIndex,
+    required LocalFile file,
+  }) : super(
+          fileIndex: fileIndex,
+          file: file,
+        );
+
+  @override
+  buildWidget(BuildContext context) {
+    final ImageProvider provider;
+    if (file is LocalUriFile) {
+      provider = ContentUriImage((file as LocalUriFile).uri);
+    } else {
+      throw ArgumentError("Invalid file");
+    }
+
+    return Padding(
+      padding: const EdgeInsets.all(2),
+      child: FittedBox(
+        clipBehavior: Clip.hardEdge,
+        fit: BoxFit.cover,
+        child: Container(
+          // arbitrary size here
+          constraints: BoxConstraints.tight(const Size(128, 128)),
+          color: AppTheme.getListItemBackgroundColor(context),
+          child: Image(
+            image: ResizeImage.resizeIfNeeded(k.photoThumbSize, null, provider),
+            filterQuality: FilterQuality.high,
+            fit: BoxFit.cover,
+            errorBuilder: (context, e, stackTrace) {
+              return Center(
+                child: Icon(
+                  Icons.image_not_supported,
+                  size: 64,
+                  color: Colors.white.withOpacity(.8),
+                ),
+              );
+            },
+          ),
+        ),
+      ),
+    );
+  }
+}
 
 class PhotoListImage extends StatelessWidget {
   const PhotoListImage({

app/lib/widget/selectable_item_stream_list_mixin.dart

@@ -14,9 +14,11 @@ import 'package:nc_photos/widget/measurable_item_list.dart';
 import 'package:nc_photos/widget/selectable.dart';
 
 abstract class SelectableItem {
+  const SelectableItem();
+
   Widget buildWidget(BuildContext context);
 
-  VoidCallback? get onTap => null;
+  bool get isTappable => false;
   bool get isSelectable => false;
   StaggeredTile get staggeredTile => const StaggeredTile.count(1, 1);
 }
@@ -28,6 +30,9 @@ mixin SelectableItemStreamListMixin<T extends StatefulWidget> on State<T> {
     _keyboardFocus.requestFocus();
   }
 
+  @protected
+  void onItemTap(SelectableItem item, int index);
+
   @protected
   Widget buildItemStreamListOuter(
     BuildContext context, {
@@ -170,7 +175,9 @@ mixin SelectableItemStreamListMixin<T extends StatefulWidget> on State<T> {
         }
       }
     } else {
-      item.onTap?.call();
+      if (item.isTappable) {
+        onItemTap(item, index);
+      }
     }
   }
 

app/lib/widget/smart_album_browser.dart

@@ -12,6 +12,7 @@ import 'package:nc_photos/entity/album/provider.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/share_handler.dart';
 import 'package:nc_photos/theme.dart';
 import 'package:nc_photos/use_case/preprocess_album.dart';
@@ -76,6 +77,11 @@ class _SmartAlbumBrowserState extends State<SmartAlbumBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<_ListItem>()?.onTap?.call();
+  }
+
   @override
   @protected
   get canEdit => false;
@@ -324,11 +330,11 @@ enum _SelectionMenuOption {
 abstract class _ListItem implements SelectableItem {
   const _ListItem({
     required this.index,
-    VoidCallback? onTap,
+    this.onTap,
-  }) : _onTap = onTap;
+  });
 
   @override
-  get onTap => _onTap;
+  get isTappable => onTap != null;
 
   @override
   get isSelectable => true;
@@ -345,7 +351,7 @@ abstract class _ListItem implements SelectableItem {
 
   final int index;
 
-  final VoidCallback? _onTap;
+  final VoidCallback? onTap;
 }
 
 abstract class _FileListItem extends _ListItem {

app/lib/widget/trashbin_browser.dart

@@ -1,23 +1,25 @@
+import 'dart:ui';
+
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:flutter_staggered_grid_view/flutter_staggered_grid_view.dart';
 import 'package:kiwi/kiwi.dart';
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
-import 'package:nc_photos/api/api_util.dart' as api_util;
 import 'package:nc_photos/app_localizations.dart';
 import 'package:nc_photos/bloc/ls_trashbin.dart';
+import 'package:nc_photos/compute_queue.dart';
 import 'package:nc_photos/debug_util.dart';
 import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file.dart';
-import 'package:nc_photos/entity/file_util.dart' as file_util;
 import 'package:nc_photos/exception_util.dart' as exception_util;
-import 'package:nc_photos/iterable_extension.dart';
 import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/language_util.dart' as language_util;
+import 'package:nc_photos/object_extension.dart';
 import 'package:nc_photos/pref.dart';
 import 'package:nc_photos/snack_bar_manager.dart';
 import 'package:nc_photos/theme.dart';
 import 'package:nc_photos/use_case/restore_trashbin.dart';
+import 'package:nc_photos/widget/builder/photo_list_item_builder.dart';
 import 'package:nc_photos/widget/empty_list_indicator.dart';
 import 'package:nc_photos/widget/handler/remove_selection_handler.dart';
 import 'package:nc_photos/widget/photo_list_item.dart';
@@ -82,6 +84,18 @@ class _TrashbinBrowserState extends State<TrashbinBrowser>
     );
   }
 
+  @override
+  onItemTap(SelectableItem item, int index) {
+    item.as<PhotoListFileItem>()?.run((fileItem) {
+      Navigator.pushNamed(
+        context,
+        TrashbinViewer.routeName,
+        arguments: TrashbinViewerArguments(
+            widget.account, _backingFiles, fileItem.fileIndex),
+      );
+    });
+  }
+
   void _initBloc() {
     _bloc = LsTrashbinBloc.of(widget.account);
     if (_bloc.state is LsTrashbinBlocInit) {
@@ -99,7 +113,9 @@ class _TrashbinBrowserState extends State<TrashbinBrowser>
   }
 
   Widget _buildContent(BuildContext context, LsTrashbinBlocState state) {
-    if (state is LsTrashbinBlocSuccess && itemStreamListItems.isEmpty) {
+    if (state is LsTrashbinBlocSuccess &&
+        !_buildItemQueue.isProcessing &&
+        itemStreamListItems.isEmpty) {
       return Column(
         children: [
           AppBar(
@@ -135,7 +151,7 @@ class _TrashbinBrowserState extends State<TrashbinBrowser>
               ),
             ),
           ),
-          if (state is LsTrashbinBlocLoading)
+          if (state is LsTrashbinBlocLoading || _buildItemQueue.isProcessing)
             const Align(
               alignment: Alignment.bottomCenter,
               child: LinearProgressIndicator(),
@@ -250,12 +266,6 @@ class _TrashbinBrowserState extends State<TrashbinBrowser>
     }
   }
 
-  void _onItemTap(int index) {
-    Navigator.pushNamed(context, TrashbinViewer.routeName,
-        arguments:
-            TrashbinViewerArguments(widget.account, _backingFiles, index));
-  }
-
   void _onEmptyTrashPressed(BuildContext context) async {
     showDialog(
       context: context,
@@ -282,7 +292,7 @@ class _TrashbinBrowserState extends State<TrashbinBrowser>
       duration: k.snackBarDurationShort,
     ));
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -335,51 +345,29 @@ class _TrashbinBrowserState extends State<TrashbinBrowser>
   }
 
   void _transformItems(List<File> files) {
-    _backingFiles = files.sorted((a, b) {
+    _buildItemQueue.addJob(
-      if (a.trashbinDeletionTime == null && b.trashbinDeletionTime == null) {
+      PhotoListItemBuilderArguments(
-        // ?
+        widget.account,
-        return 0;
+        files,
-      } else if (a.trashbinDeletionTime == null) {
+        sorter: _fileSorter,
-        return -1;
+        locale: language_util.getSelectedLocale() ??
-      } else if (b.trashbinDeletionTime == null) {
+            PlatformDispatcher.instance.locale,
-        return 1;
+      ),
-      } else {
+      buildPhotoListItem,
-        return b.trashbinDeletionTime!.compareTo(a.trashbinDeletionTime!);
+      (result) {
-      }
+        if (mounted) {
+          setState(() {
+            _backingFiles = result.backingFiles;
+            itemStreamListItems = result.listItems;
           });
-
-    itemStreamListItems = () sync* {
-      for (int i = 0; i < _backingFiles.length; ++i) {
-        final f = _backingFiles[i];
-
-        final previewUrl = api_util.getFilePreviewUrl(widget.account, f,
-            width: k.photoThumbSize, height: k.photoThumbSize);
-        if (file_util.isSupportedImageFormat(f)) {
-          yield _ImageListItem(
-            file: f,
-            account: widget.account,
-            previewUrl: previewUrl,
-            onTap: () => _onItemTap(i),
-          );
-        } else if (file_util.isSupportedVideoFormat(f)) {
-          yield _VideoListItem(
-            file: f,
-            account: widget.account,
-            previewUrl: previewUrl,
-            onTap: () => _onItemTap(i),
-          );
-        } else {
-          _log.shout(
-              "[_transformItems] Unsupported file format: ${f.contentType}");
         }
-      }
+      },
-    }()
+    );
-        .toList();
   }
 
   Future<void> _deleteSelected() async {
     final selectedFiles = selectedListItems
-        .whereType<_FileListItem>()
+        .whereType<PhotoListFileItem>()
         .map((e) => e.file)
         .toList();
     setState(() {
@@ -404,87 +392,15 @@ class _TrashbinBrowserState extends State<TrashbinBrowser>
 
   var _backingFiles = <File>[];
 
+  final _buildItemQueue =
+      ComputeQueue<PhotoListItemBuilderArguments, PhotoListItemBuilderResult>();
+
   var _thumbZoomLevel = 0;
   int get _thumbSize => photo_list_util.getThumbSize(_thumbZoomLevel);
 
   static final _log = Logger("widget.trashbin_browser._TrashbinBrowserState");
 }
 
-abstract class _ListItem implements SelectableItem {
-  _ListItem({
-    VoidCallback? onTap,
-  }) : _onTap = onTap;
-
-  @override
-  get onTap => _onTap;
-
-  @override
-  get isSelectable => true;
-
-  @override
-  get staggeredTile => const StaggeredTile.count(1, 1);
-
-  final VoidCallback? _onTap;
-}
-
-abstract class _FileListItem extends _ListItem {
-  _FileListItem({
-    required this.file,
-    VoidCallback? onTap,
-  }) : super(onTap: onTap);
-
-  @override
-  operator ==(Object other) {
-    return other is _FileListItem && file.path == other.file.path;
-  }
-
-  @override
-  get hashCode => file.path.hashCode;
-
-  final File file;
-}
-
-class _ImageListItem extends _FileListItem {
-  _ImageListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListImage(
-      account: account,
-      previewUrl: previewUrl,
-      isGif: file.contentType == "image/gif",
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}
-
-class _VideoListItem extends _FileListItem {
-  _VideoListItem({
-    required File file,
-    required this.account,
-    required this.previewUrl,
-    VoidCallback? onTap,
-  }) : super(file: file, onTap: onTap);
-
-  @override
-  buildWidget(BuildContext context) {
-    return PhotoListVideo(
-      account: account,
-      previewUrl: previewUrl,
-    );
-  }
-
-  final Account account;
-  final String previewUrl;
-}
-
 enum _AppBarMenuOption {
   empty,
 }
@@ -492,3 +408,16 @@ enum _AppBarMenuOption {
 enum _SelectionAppBarMenuOption {
   delete,
 }
+
+int _fileSorter(File a, File b) {
+  if (a.trashbinDeletionTime == null && b.trashbinDeletionTime == null) {
+    // ?
+    return 0;
+  } else if (a.trashbinDeletionTime == null) {
+    return -1;
+  } else if (b.trashbinDeletionTime == null) {
+    return 1;
+  } else {
+    return b.trashbinDeletionTime!.compareTo(a.trashbinDeletionTime!);
+  }
+}

app/test/entity/webdav_response_parser_test.dart

@@ -18,7 +18,7 @@ void main() {
   });
 }
 
-void _files() {
+Future<void> _files() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -42,7 +42,7 @@ void _files() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Nextcloud intro.mp4",
@@ -57,7 +57,7 @@ void _files() {
   ]);
 }
 
-void _files404props() {
+Future<void> _files404props() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -88,7 +88,7 @@ void _files404props() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Nextcloud intro.mp4",
@@ -103,7 +103,7 @@ void _files404props() {
   ]);
 }
 
-void _filesMetadata() {
+Future<void> _filesMetadata() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -128,7 +128,7 @@ void _filesMetadata() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Photos/Nextcloud community.jpg",
@@ -149,7 +149,7 @@ void _filesMetadata() {
   ]);
 }
 
-void _filesIsArchived() {
+Future<void> _filesIsArchived() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -173,7 +173,7 @@ void _filesIsArchived() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Photos/Nextcloud community.jpg",
@@ -188,7 +188,7 @@ void _filesIsArchived() {
   ]);
 }
 
-void _filesOverrideDateTime() {
+Future<void> _filesOverrideDateTime() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -212,7 +212,7 @@ void _filesOverrideDateTime() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Photos/Nextcloud community.jpg",
@@ -227,7 +227,7 @@ void _filesOverrideDateTime() {
   ]);
 }
 
-void _filesMultiple() {
+Future<void> _filesMultiple() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -267,7 +267,7 @@ void _filesMultiple() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Nextcloud intro.mp4",
@@ -298,7 +298,7 @@ void _filesMultiple() {
   ]);
 }
 
-void _filesDir() {
+Future<void> _filesDir() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -330,7 +330,7 @@ void _filesDir() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Photos",
@@ -343,7 +343,7 @@ void _filesDir() {
   ]);
 }
 
-void _filesServerHostedInSubdir() {
+Future<void> _filesServerHostedInSubdir() async {
   final xml = XmlDocument.parse("""
 <?xml version="1.0"?>
 <d:multistatus xmlns:d="DAV:"
@@ -367,7 +367,7 @@ void _filesServerHostedInSubdir() {
 	</d:response>
 </d:multistatus>
 """);
-  final results = WebdavResponseParser().parseFiles(xml);
+  final results = await WebdavResponseParser().parseFiles(xml);
   expect(results, [
     File(
       path: "remote.php/dav/files/admin/Nextcloud intro.mp4",