fix: enqueue assets in batches for uploads

mobile/lib/infrastructure/repositories/backup.repository.dart

@@ -81,7 +81,7 @@ class DriftBackupRepository extends DriftDatabaseRepository {
     );
   }
 
-  Future<List<LocalAsset>> getCandidates(String userId, {bool onlyHashed = true}) async {
+  Future<List<LocalAsset>> getCandidates(String userId, {bool onlyHashed = true, int? limit}) async {
     final selectedAlbumIds = _db.localAlbumEntity.selectOnly(distinct: true)
       ..addColumns([_db.localAlbumEntity.id])
       ..where(_db.localAlbumEntity.backupSelection.equalsValue(BackupSelection.selected));
@@ -112,6 +112,10 @@ class DriftBackupRepository extends DriftDatabaseRepository {
       query.where((lae) => lae.checksum.isNotNull());
     }
 
+    if (limit != null) {
+      query.limit(limit);
+    }
+
     return query.map((localAsset) => localAsset.toDto()).get();
   }
 }

mobile/lib/main.dart

@@ -25,6 +25,7 @@ import 'package:immich_mobile/providers/asset_viewer/share_intent_upload.provide
 import 'package:immich_mobile/providers/db.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/db.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/platform.provider.dart';
+import 'package:immich_mobile/providers/infrastructure/upload_timer.provider.dart';
 import 'package:immich_mobile/providers/locale_provider.dart';
 import 'package:immich_mobile/providers/routes.provider.dart';
 import 'package:immich_mobile/providers/theme.provider.dart';
@@ -211,6 +212,8 @@ class ImmichAppState extends ConsumerState<ImmichApp> with WidgetsBindingObserve
     WidgetsBinding.instance.addPostFrameCallback((_) {
       // needs to be delayed so that EasyLocalization is working
       if (Store.isBetaTimelineEnabled) {
+        // Start upload timer
+        ref.read(uploadTimerProvider.notifier).start();
         ref.read(backgroundServiceProvider).disableService();
         ref.read(backgroundWorkerFgServiceProvider).enable();
         if (Platform.isAndroid) {

mobile/lib/providers/app_life_cycle.provider.dart

@@ -16,6 +16,7 @@ import 'package:immich_mobile/providers/backup/ios_background_settings.provider.
 import 'package:immich_mobile/providers/backup/manual_upload.provider.dart';
 import 'package:immich_mobile/providers/gallery_permission.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/platform.provider.dart';
+import 'package:immich_mobile/providers/infrastructure/upload_timer.provider.dart';
 import 'package:immich_mobile/providers/memory.provider.dart';
 import 'package:immich_mobile/providers/notification_permission.provider.dart';
 import 'package:immich_mobile/providers/server_info.provider.dart';
@@ -139,6 +140,7 @@ class AppLifeCycleNotifier extends StateNotifier<AppLifeCycleEnum> {
 
   Future<void> _handleBetaTimelineResume() async {
     _ref.read(backupProvider.notifier).cancelBackup();
+    _ref.read(uploadTimerProvider.notifier).start();
     unawaited(_ref.read(backgroundWorkerLockServiceProvider).lock());
 
     // Give isolates time to complete any ongoing database transactions
@@ -216,6 +218,7 @@ class AppLifeCycleNotifier extends StateNotifier<AppLifeCycleEnum> {
 
     try {
       if (Store.isBetaTimelineEnabled) {
+        _ref.read(uploadTimerProvider.notifier).stop();
         unawaited(_ref.read(backgroundWorkerLockServiceProvider).unlock());
       }
       await _performPause();
@@ -250,6 +253,7 @@ class AppLifeCycleNotifier extends StateNotifier<AppLifeCycleEnum> {
     state = AppLifeCycleEnum.detached;
 
     if (Store.isBetaTimelineEnabled) {
+      _ref.read(uploadTimerProvider.notifier).stop();
       unawaited(_ref.read(backgroundWorkerLockServiceProvider).unlock());
     }
 

mobile/lib/providers/infrastructure/upload_timer.provider.dart

@@ -0,0 +1,76 @@
+import 'dart:async';
+
+import 'package:background_downloader/background_downloader.dart';
+import 'package:immich_mobile/constants/constants.dart';
+import 'package:immich_mobile/providers/app_settings.provider.dart';
+import 'package:immich_mobile/providers/backup/drift_backup.provider.dart';
+import 'package:immich_mobile/providers/user.provider.dart';
+import 'package:immich_mobile/services/app_settings.service.dart';
+import 'package:logging/logging.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+class UploadTimerNotifier extends Notifier<bool> {
+  Timer? _timer;
+  final _timerLogger = Logger('UploadTimer');
+  static const _refreshDuration = Duration(seconds: 10);
+
+  void start() {
+    if (state) {
+      return;
+    }
+
+    state = true;
+    _schedule();
+  }
+
+  void stop() {
+    if (!state) {
+      return;
+    }
+
+    _timer?.cancel();
+    _timer = null;
+    state = false;
+  }
+
+  void _schedule() {
+    _timer?.cancel();
+    _timer = Timer(_refreshDuration, () async {
+      if (!state) {
+        return;
+      }
+      await _backup();
+      if (state) {
+        _schedule();
+      }
+    });
+  }
+
+  Future<void> _backup() async {
+    final isBackupEnabled = ref.read(appSettingsServiceProvider).getSetting(AppSettingsEnum.enableBackup);
+    if (!isBackupEnabled) {
+      _timerLogger.fine("UploadTimer: Backup is disabled, skipping backup start.");
+      return;
+    }
+
+    final tasks = await FileDownloader().allTasks(group: kBackupGroup);
+    final currentUserId = ref.read(currentUserProvider)?.id;
+    if (tasks.isEmpty && currentUserId != null) {
+      ref.read(driftBackupProvider.notifier).startBackup(currentUserId);
+    } else {
+      _timerLogger.fine("UploadTimer: There are still active upload tasks - ${tasks.length}, skipping backup start.");
+    }
+  }
+
+  @override
+  bool build() {
+    Future.microtask(start);
+    ref.onDispose(() {
+      _timer?.cancel();
+    });
+    // Timer is not running yet
+    return false;
+  }
+}
+
+final uploadTimerProvider = NotifierProvider<UploadTimerNotifier, bool>(UploadTimerNotifier.new);

mobile/lib/services/upload.service.dart

@@ -121,33 +121,23 @@ class UploadService {
 
     shouldAbortQueuingTasks = false;
 
-    final candidates = await _backupRepository.getCandidates(userId);
+    final candidates = await _backupRepository.getCandidates(userId, limit: 100);
     if (candidates.isEmpty) {
       return;
     }
 
-    const batchSize = 100;
-    int count = 0;
-    for (int i = 0; i < candidates.length; i += batchSize) {
-      if (shouldAbortQueuingTasks) {
-        break;
+    List<UploadTask> tasks = [];
+    for (final asset in candidates) {
+      final task = await _getUploadTask(asset);
+      if (task != null) {
+        tasks.add(task);
       }
+    }
 
-      final batch = candidates.skip(i).take(batchSize).toList();
-      List<UploadTask> tasks = [];
-      for (final asset in batch) {
-        final task = await _getUploadTask(asset);
-        if (task != null) {
-          tasks.add(task);
-        }
-      }
+    if (tasks.isNotEmpty && !shouldAbortQueuingTasks) {
+      await enqueueTasks(tasks);
 
-      if (tasks.isNotEmpty && !shouldAbortQueuingTasks) {
-        count += tasks.length;
-        await enqueueTasks(tasks);
-
-        onEnqueueTasks(EnqueueStatus(enqueueCount: count, totalCount: candidates.length));
-      }
+      onEnqueueTasks(EnqueueStatus(enqueueCount: tasks.length, totalCount: candidates.length));
     }
   }