chore: undo unrelated button change

mobile/lib/domain/services/timeline.service.dart

@@ -182,18 +182,6 @@ class TimelineService {
     return _buffer.slice(start, start + count);
   }
 
-  /// Reads a range without disturbing the buffer; queries the source if it isn't resident.
-  Future<List<BaseAsset>> getAssetsRange(int index, int count) async {
-    if (index < 0 || count <= 0 || index >= _totalAssets) {
-      return const [];
-    }
-    final clamped = math.min(count, _totalAssets - index);
-    if (hasRange(index, clamped)) {
-      return getAssets(index, clamped);
-    }
-    return _assetSource(index, clamped);
-  }
-
   // Preload assets around the given index for asset viewer
   Future<void> preloadAssets(int index) => _mutex.run(() => _loadAssets(index, math.min(5, _totalAssets - index)));
 

mobile/lib/presentation/widgets/timeline/drag_selection_controller.dart

@@ -1,175 +0,0 @@
-import 'dart:collection';
-
-import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
-
-// Tracks the [anchor..current] range selected by a drag. The in-buffer part of
-// each tick is selected synchronously so it follows the finger without racing;
-// the rare beyond-buffer part is read async (applied only if still in range) and
-// [end] reads whatever is still missing so the final range always lands.
-class DragSelectionController {
-  DragSelectionController({required this.getAssetSafe, required this.getAssetsRange, required this.onChange});
-
-  final BaseAsset? Function(int index) getAssetSafe;
-  final Future<List<BaseAsset>> Function(int index, int count) getAssetsRange;
-  final void Function(Set<BaseAsset> select, Set<BaseAsset> deselect) onChange;
-
-  final HashMap<int, BaseAsset> _selected = HashMap();
-  // Indices the buffer didn't hold yet (the edge outran the async buffer-load on a
-  // fast scroll); read in by _extendPending and guaranteed by end().
-  final Set<int> _pending = {};
-  int? _anchor;
-  int? _lo;
-  int? _hi;
-  bool _disposed = false;
-
-  // Call before starting a new drag so a previous drag's in-flight read can't
-  // leak into the new selection.
-  void dispose() => _disposed = true;
-
-  void _emit(Set<BaseAsset> select, Set<BaseAsset> deselect) {
-    if (_disposed) {
-      return;
-    }
-    onChange(select, deselect);
-  }
-
-  void start(int anchor) {
-    _selected.clear();
-    _pending.clear();
-    _anchor = anchor;
-    _lo = anchor;
-    _hi = anchor;
-    _select(anchor);
-    _extendPending();
-  }
-
-  void enter(int current) {
-    final anchor = _anchor;
-    if (anchor == null || _lo == null || _hi == null) {
-      return;
-    }
-    final ns = current < anchor ? current : anchor;
-    final ne = current < anchor ? anchor : current;
-    final ps = _lo!;
-    final pe = _hi!;
-    if (ns == ps && ne == pe) {
-      return;
-    }
-
-    final toSelect = <BaseAsset>{};
-    final toDeselect = <BaseAsset>{};
-
-    _forEach(ps, ns - 1, (k) => _removeIndex(k, toDeselect));
-    _forEach(ne + 1, pe, (k) => _removeIndex(k, toDeselect));
-    _forEach(ns, ps - 1, (k) => _addIndex(k, toSelect));
-    _forEach(pe + 1, ne, (k) => _addIndex(k, toSelect));
-
-    _lo = ns;
-    _hi = ne;
-
-    if (toSelect.isNotEmpty || toDeselect.isNotEmpty) {
-      _emit(toSelect, toDeselect);
-    }
-    _extendPending();
-  }
-
-  Future<void> end() async {
-    final lo = _lo;
-    final hi = _hi;
-    if (lo == null || hi == null) {
-      return;
-    }
-    final missing = <int>[];
-    for (var k = lo; k <= hi; k++) {
-      if (!_selected.containsKey(k)) {
-        missing.add(k);
-      }
-    }
-    if (missing.isEmpty) {
-      return;
-    }
-    final from = missing.first;
-    final assets = await getAssetsRange(from, missing.last - from + 1);
-    final missingSet = missing.toSet();
-    final toSelect = <BaseAsset>{};
-    for (var i = 0; i < assets.length; i++) {
-      final idx = from + i;
-      if (missingSet.contains(idx) && !_selected.containsKey(idx)) {
-        _selected[idx] = assets[i];
-        _pending.remove(idx);
-        toSelect.add(assets[i]);
-      }
-    }
-    if (toSelect.isNotEmpty) {
-      _emit(toSelect, const {});
-    }
-  }
-
-  void _select(int index) {
-    final asset = getAssetSafe(index);
-    if (asset != null) {
-      _selected[index] = asset;
-      _pending.remove(index);
-      _emit({asset}, const {});
-    } else {
-      _pending.add(index);
-    }
-  }
-
-  void _addIndex(int index, Set<BaseAsset> toSelect) {
-    if (_selected.containsKey(index)) {
-      return;
-    }
-    final asset = getAssetSafe(index);
-    if (asset != null) {
-      _selected[index] = asset;
-      _pending.remove(index);
-      toSelect.add(asset);
-    } else {
-      _pending.add(index);
-    }
-  }
-
-  void _removeIndex(int index, Set<BaseAsset> toDeselect) {
-    _pending.remove(index);
-    final asset = _selected.remove(index);
-    if (asset != null) {
-      toDeselect.add(asset);
-    }
-  }
-
-  Future<void> _extendPending() async {
-    if (_pending.isEmpty) {
-      return;
-    }
-    var from = _pending.first;
-    var to = _pending.first;
-    for (final k in _pending) {
-      if (k < from) {
-        from = k;
-      }
-      if (k > to) {
-        to = k;
-      }
-    }
-    final assets = await getAssetsRange(from, to - from + 1);
-    final toSelect = <BaseAsset>{};
-    for (var i = 0; i < assets.length; i++) {
-      final idx = from + i;
-      if (_pending.contains(idx) && _lo != null && idx >= _lo! && idx <= _hi!) {
-        _selected[idx] = assets[i];
-        toSelect.add(assets[i]);
-      }
-    }
-    _pending.removeWhere((idx) => _selected.containsKey(idx));
-    if (toSelect.isNotEmpty) {
-      _emit(toSelect, const {});
-    }
-  }
-
-  void _forEach(int lo, int hi, void Function(int) fn) {
-    for (var k = lo; k <= hi; k++) {
-      fn(k);
-    }
-  }
-}

mobile/lib/presentation/widgets/timeline/timeline.widget.dart

@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:collection';
 import 'dart:math' as math;
 
 import 'package:collection/collection.dart';
@@ -7,6 +8,7 @@ import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
 import 'package:immich_mobile/domain/models/events.model.dart';
 import 'package:immich_mobile/domain/models/timeline.model.dart';
 import 'package:immich_mobile/domain/utils/event_stream.dart';
@@ -18,7 +20,6 @@ import 'package:immich_mobile/presentation/widgets/timeline/constants.dart';
 import 'package:immich_mobile/presentation/widgets/timeline/scrubber.widget.dart';
 import 'package:immich_mobile/presentation/widgets/timeline/segment.model.dart';
 import 'package:immich_mobile/presentation/widgets/timeline/timeline.state.dart';
-import 'package:immich_mobile/presentation/widgets/timeline/drag_selection_controller.dart';
 import 'package:immich_mobile/presentation/widgets/timeline/timeline_drag_region.dart';
 import 'package:immich_mobile/providers/infrastructure/readonly_mode.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/settings.provider.dart';
@@ -28,27 +29,6 @@ import 'package:immich_mobile/widgets/common/immich_sliver_app_bar.dart';
 import 'package:immich_mobile/widgets/common/mesmerizing_sliver_app_bar.dart';
 import 'package:immich_mobile/widgets/common/selection_sliver_app_bar.dart';
 
-// First asset index of the row shown at [offset]. Pure for testing.
-@visibleForTesting
-int? assetIndexAtOffset(
-  List<Segment> segments,
-  double offset, {
-  required int columnCount,
-  required double maxScrollExtent,
-}) {
-  final clamped = offset.clamp(0.0, maxScrollExtent);
-  final segment = segments.findByOffset(clamped) ?? segments.lastOrNull;
-  if (segment == null) {
-    return null;
-  }
-  final rowIndex = segment.getMinChildIndexForScrollOffset(clamped);
-  if (rowIndex > segment.firstIndex) {
-    final rowIndexInSegment = rowIndex - (segment.firstIndex + 1);
-    return segment.firstAssetIndex + rowIndexInSegment * columnCount;
-  }
-  return segment.firstAssetIndex;
-}
-
 class Timeline extends StatelessWidget {
   const Timeline({
     super.key,
@@ -160,10 +140,9 @@ class _SliverTimelineState extends ConsumerState<_SliverTimeline> {
   StreamSubscription? _eventSubscription;
 
   // Drag selection state
-  static const _autoScrollStep = 175.0;
-  static const _autoScrollDuration = Duration(milliseconds: 125);
   bool _dragging = false;
-  DragSelectionController? _dragController;
+  TimelineAssetIndex? _dragAnchorIndex;
+  final Set<BaseAsset> _draggedAssets = HashSet();
   ScrollPhysics? _scrollPhysics;
 
   int _perRow = 4;
@@ -247,18 +226,26 @@ class _SliverTimelineState extends ConsumerState<_SliverTimeline> {
     EventStream.shared.emit(MultiSelectToggleEvent(isEnabled));
   }
 
-  int? _getCurrentAssetIndex(List<Segment> segments) => _assetIndexAtOffset(segments, _scrollController.offset);
-
-  int? _assetIndexAtOffset(List<Segment> segments, double offset) => assetIndexAtOffset(
-    segments,
-    offset,
-    columnCount: ref.read(timelineArgsProvider).columnCount,
-    maxScrollExtent: _scrollController.position.maxScrollExtent,
-  );
+  int? _getCurrentAssetIndex(List<Segment> segments) {
+    final currentOffset = _scrollController.offset.clamp(0.0, _scrollController.position.maxScrollExtent);
+    final segment = segments.findByOffset(currentOffset) ?? segments.lastOrNull;
+    int? targetAssetIndex;
+    if (segment != null) {
+      final rowIndex = segment.getMinChildIndexForScrollOffset(currentOffset);
+      if (rowIndex > segment.firstIndex) {
+        final rowIndexInSegment = rowIndex - (segment.firstIndex + 1);
+        final assetsPerRow = ref.read(timelineArgsProvider).columnCount;
+        final assetIndexInSegment = rowIndexInSegment * assetsPerRow;
+        targetAssetIndex = segment.firstAssetIndex + assetIndexInSegment;
+      } else {
+        targetAssetIndex = segment.firstAssetIndex;
+      }
+    }
+    return targetAssetIndex;
+  }
 
   @override
   void dispose() {
-    _dragController?.dispose();
     _scrollController.dispose();
     _eventSubscription?.cancel();
     super.dispose();
@@ -308,21 +295,9 @@ class _SliverTimelineState extends ConsumerState<_SliverTimeline> {
 
   // Drag selection methods
   void _setDragStartIndex(TimelineAssetIndex index) {
-    // Stop the old drag's controller so its in-flight read can't leak into this one.
-    _dragController?.dispose();
-    final timelineService = ref.read(timelineServiceProvider);
-    _dragController = DragSelectionController(
-      getAssetSafe: timelineService.getAssetSafe,
-      getAssetsRange: timelineService.getAssetsRange,
-      onChange: (select, deselect) {
-        if (!mounted) {
-          return;
-        }
-        ref.read(multiSelectProvider.notifier).selectRange(select, deselect);
-      },
-    )..start(index.assetIndex);
     setState(() {
       _scrollPhysics = const ClampingScrollPhysics();
+      _dragAnchorIndex = index;
       _dragging = true;
     });
   }
@@ -338,12 +313,8 @@ class _SliverTimelineState extends ConsumerState<_SliverTimeline> {
     });
     setState(() {
       _dragging = false;
+      _draggedAssets.clear();
     });
-    // Apply the full final range even if a read is still in flight on lift.
-    final finishing = _dragController?.end();
-    if (finishing != null) {
-      unawaited(finishing);
-    }
     final timelineState = ref.read(timelineStateProvider.notifier);
     Future.delayed(const Duration(milliseconds: 300), () {
       timelineState.setScrolling(false);
@@ -351,33 +322,42 @@ class _SliverTimelineState extends ConsumerState<_SliverTimeline> {
   }
 
   void _dragScroll(ScrollDirection direction) {
-    final position = _scrollController.position;
-    final step = direction == ScrollDirection.forward ? _autoScrollStep : -_autoScrollStep;
-    final target = (_scrollController.offset + step).clamp(0.0, position.maxScrollExtent);
-    _scrollController.animateTo(target, duration: _autoScrollDuration, curve: Curves.easeOut);
-
-    // A held finger emits no move events, so extend the selection to the asset
-    // at the leading edge of the scroll instead.
-    final controller = _dragController;
-    if (controller == null) {
-      return;
-    }
-    final segments = ref.read(timelineSegmentProvider).valueOrNull;
-    if (segments == null) {
-      return;
-    }
-    final edgeOffset = direction == ScrollDirection.forward ? target + position.viewportDimension : target;
-    final edgeIndex = _assetIndexAtOffset(segments, edgeOffset);
-    if (edgeIndex != null) {
-      controller.enter(edgeIndex);
-    }
+    _scrollController.animateTo(
+      _scrollController.offset + (direction == ScrollDirection.forward ? 175 : -175),
+      duration: const Duration(milliseconds: 125),
+      curve: Curves.easeOut,
+    );
   }
 
   void _handleDragAssetEnter(TimelineAssetIndex index) {
-    if (!_dragging) {
+    if (_dragAnchorIndex == null || !_dragging) {
       return;
     }
-    _dragController?.enter(index.assetIndex);
+
+    final timelineService = ref.read(timelineServiceProvider);
+    final dragAnchorIndex = _dragAnchorIndex!;
+
+    // Calculate the range of assets to select
+    final startIndex = math.min(dragAnchorIndex.assetIndex, index.assetIndex);
+    final endIndex = math.max(dragAnchorIndex.assetIndex, index.assetIndex);
+    final count = endIndex - startIndex + 1;
+
+    // Load the assets in the range
+    if (timelineService.hasRange(startIndex, count)) {
+      final selectedAssets = timelineService.getAssets(startIndex, count);
+
+      // Clear previous drag selection and add new range
+      final multiSelectNotifier = ref.read(multiSelectProvider.notifier);
+      for (final asset in _draggedAssets) {
+        multiSelectNotifier.deselectAsset(asset);
+      }
+      _draggedAssets.clear();
+
+      for (final asset in selectedAssets) {
+        multiSelectNotifier.selectAsset(asset);
+        _draggedAssets.add(asset);
+      }
+    }
   }
 
   @override

mobile/lib/providers/timeline/multiselect.provider.dart

@@ -97,15 +97,6 @@ class MultiSelectNotifier extends Notifier<MultiSelectState> {
     }
   }
 
-  // Drops the previous drag range and adds the new one in a single update. The
-  // full-set copy per drag tick is the accepted cost of immutable state.
-  void selectRange(Set<BaseAsset> toSelect, Set<BaseAsset> toDeselect) {
-    final selectedAssets = state.selectedAssets.toSet()
-      ..removeAll(toDeselect)
-      ..addAll(toSelect);
-    state = state.copyWith(selectedAssets: selectedAssets);
-  }
-
   void reset() {
     state = const MultiSelectState(selectedAssets: {}, lockedSelectionAssets: {}, forceEnable: false);
   }

mobile/test/unit/presentation/widgets/timeline/asset_index_at_offset_test.dart

@@ -1,60 +0,0 @@
-import 'package:flutter_test/flutter_test.dart';
-import 'package:immich_mobile/domain/models/timeline.model.dart';
-import 'package:immich_mobile/presentation/widgets/timeline/fixed/segment.model.dart';
-import 'package:immich_mobile/presentation/widgets/timeline/segment.model.dart';
-import 'package:immich_mobile/presentation/widgets/timeline/timeline.widget.dart';
-
-void main() {
-  // Two day-segments, 4 columns, 8 assets each (2 rows). header 50, tile 100, no spacing.
-  //   A: header@[0,50)  rows@50,150   assets 0..7    offset [0,250]
-  //   B: header@[250,300) rows@300,400 assets 8..15  offset [250,500]
-  const columnCount = 4;
-  const maxScrollExtent = 500.0;
-  final segments = <Segment>[
-    const FixedSegment(
-      firstIndex: 0,
-      lastIndex: 2,
-      startOffset: 0,
-      endOffset: 250,
-      firstAssetIndex: 0,
-      bucket: Bucket(assetCount: 8),
-      tileHeight: 100,
-      columnCount: columnCount,
-      headerExtent: 50,
-      spacing: 0,
-      header: HeaderType.day,
-    ),
-    const FixedSegment(
-      firstIndex: 3,
-      lastIndex: 5,
-      startOffset: 250,
-      endOffset: 500,
-      firstAssetIndex: 8,
-      bucket: Bucket(assetCount: 8),
-      tileHeight: 100,
-      columnCount: columnCount,
-      headerExtent: 50,
-      spacing: 0,
-      header: HeaderType.day,
-    ),
-  ];
-
-  int? at(double offset) =>
-      assetIndexAtOffset(segments, offset, columnCount: columnCount, maxScrollExtent: maxScrollExtent);
-
-  test('maps an offset to the first asset of the row shown there', () {
-    expect(at(0), 0); // top of segment A
-    expect(at(150), 4); // second row of A
-    expect(at(350), 8); // first row of B
-    expect(at(450), 12); // second row of B
-  });
-
-  test('clamps offsets outside the scroll range', () {
-    expect(at(-100), 0); // below the top -> first asset
-    expect(at(9999), at(maxScrollExtent)); // past the end -> same as the max offset
-  });
-
-  test('returns null for empty segments', () {
-    expect(assetIndexAtOffset(const [], 100, columnCount: columnCount, maxScrollExtent: maxScrollExtent), isNull);
-  });
-}

mobile/test/unit/presentation/widgets/timeline/drag_selection_controller_test.dart

@@ -1,157 +0,0 @@
-import 'dart:async';
-
-import 'package:flutter_test/flutter_test.dart';
-import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
-import 'package:immich_mobile/presentation/widgets/timeline/drag_selection_controller.dart';
-
-import '../../../factories/remote_asset_factory.dart';
-
-void main() {
-  const total = 50;
-  late List<BaseAsset> all;
-  late Set<int> inBuffer; // indices getAssetSafe resolves synchronously
-  late List<Completer<List<BaseAsset>>> reads; // pending async reads, completed manually
-  late List<({int from, int count})> readArgs;
-  late Set<BaseAsset> selected;
-  late DragSelectionController sut;
-
-  Set<BaseAsset> range(int lo, int hi) => {for (var i = lo; i <= hi; i++) all[i]};
-
-  void completeRead(int i) {
-    final a = readArgs[i];
-    reads[i].complete([for (var k = a.from; k < a.from + a.count && k < total; k++) all[k]]);
-  }
-
-  Future<void> settle() => Future(() {});
-
-  setUp(() {
-    all = List.generate(total, (i) => RemoteAssetFactory.create(id: 'a${i.toString().padLeft(3, '0')}'));
-    inBuffer = {for (var i = 0; i < total; i++) i}; // default: everything buffered (sync)
-    reads = [];
-    readArgs = [];
-    selected = {};
-    sut = DragSelectionController(
-      getAssetSafe: (i) => inBuffer.contains(i) ? all[i] : null,
-      getAssetsRange: (from, count) {
-        final c = Completer<List<BaseAsset>>();
-        reads.add(c);
-        readArgs.add((from: from, count: count));
-        return c.future;
-      },
-      onChange: (select, deselect) {
-        selected
-          ..addAll(select)
-          ..removeAll(deselect);
-      },
-    );
-  });
-
-  group('live selection (all in buffer, synchronous)', () {
-    test('dragging down selects the whole range as it grows', () {
-      sut.start(2);
-      sut.enter(6);
-      sut.enter(12);
-      expect(selected, range(2, 12));
-      expect(reads, isEmpty, reason: 'everything buffered -> no async read');
-    });
-
-    test('dragging back up toward the anchor deselects the shrunk tail', () {
-      sut.start(2);
-      sut.enter(12);
-      expect(selected, range(2, 12));
-      sut.enter(6); // reverse
-      expect(selected, range(2, 6));
-      sut.enter(3); // reverse more
-      expect(selected, range(2, 3));
-    });
-
-    test('dragging past the anchor flips the range', () {
-      sut.start(10);
-      sut.enter(14);
-      expect(selected, range(10, 14));
-      sut.enter(7); // crosses the anchor
-      expect(selected, range(7, 10));
-    });
-  });
-
-  group('beyond-buffer (async)', () {
-    setUp(() => inBuffer = {}); // nothing buffered -> every tile needs an async read
-
-    test('drag-end fills the full range even if every live read is still in flight', () async {
-      sut.start(0);
-      sut.enter(20);
-      // simulate the real-rate race: none of the in-drag reads have completed
-      expect(selected, isEmpty);
-
-      final ending = sut.end();
-      // end() issues its own read for the missing range; complete it
-      completeRead(reads.length - 1);
-      await ending;
-
-      expect(selected, range(0, 20), reason: 'final range must always apply on drag-end');
-    });
-
-    test('out-of-order live read completions never corrupt the selection', () async {
-      sut.start(0); // issues read for [0,1]
-      sut.enter(10); // issues read for [0,11]
-      sut.enter(20); // issues read for [0,21]
-      expect(reads.length, 3);
-
-      // complete newest first, then older ones (out of order)
-      completeRead(2);
-      await settle();
-      completeRead(1);
-      await settle();
-      completeRead(0);
-      await settle();
-
-      expect(selected, range(0, 20));
-
-      final ending = sut.end();
-      await ending; // nothing missing -> no extra read
-      expect(selected, range(0, 20));
-    });
-
-    test('a disposed controller never emits when its in-flight read resolves', () async {
-      sut.start(0); // read [0,1] (pending, in flight)
-      sut.enter(20); // read [0,21] (pending, in flight)
-      expect(selected, isEmpty);
-
-      // a new drag starts -> the old controller is disposed
-      final ending = sut.end(); // issues end()'s fill read
-      sut.dispose();
-
-      // every in-flight read for the old controller now resolves
-      for (var i = 0; i < reads.length; i++) {
-        if (!reads[i].isCompleted) {
-          completeRead(i);
-        }
-      }
-      await ending;
-      await settle();
-
-      expect(selected, isEmpty, reason: 'a disposed controller must not leak into the new selection');
-    });
-
-    test('a late read for tiles dragged back out of range is ignored', () async {
-      sut.start(0); // read [0,1]
-      sut.enter(20); // read [0,21]
-      sut.enter(5); // shrink back; read [0,6]
-      // complete the stale wide read AFTER the shrink
-      completeRead(1); // [0,21]
-      await settle();
-      // indices 6..20 left the range -> must not be selected
-      expect(selected.intersection(range(6, 20)), isEmpty);
-
-      final ending = sut.end();
-      // complete any read end() issued for the (now smaller) missing range
-      for (var i = 0; i < reads.length; i++) {
-        if (!reads[i].isCompleted) {
-          completeRead(i);
-        }
-      }
-      await ending;
-      expect(selected, range(0, 5));
-    });
-  });
-}

mobile/test/unit/services/timeline_service_test.dart

@@ -1,100 +0,0 @@
-import 'package:flutter_test/flutter_test.dart';
-import 'package:immich_mobile/constants/constants.dart';
-import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
-import 'package:immich_mobile/domain/models/timeline.model.dart';
-import 'package:immich_mobile/domain/services/timeline.service.dart';
-
-import '../factories/remote_asset_factory.dart';
-
-void main() {
-  // total must exceed the sliding buffer so it cannot hold the whole library at once
-  const total = 2000;
-  late List<BaseAsset> all;
-  late TimelineService sut;
-
-  TimelineService buildService() {
-    all = List.generate(total, (i) => RemoteAssetFactory.create(id: 'a${i.toString().padLeft(5, '0')}'));
-    return TimelineService((
-      assetSource: (index, count) async {
-        final end = (index + count) > total ? total : index + count;
-        return all.sublist(index, end);
-      },
-      bucketSource: () => Stream.value([const Bucket(assetCount: total)]),
-      origin: TimelineOrigin.main,
-    ));
-  }
-
-  Future<void> settle() => Future.delayed(const Duration(milliseconds: 10));
-
-  setUp(() async {
-    sut = buildService();
-    await settle(); // let the bucket subscription load the first batch and set totalAssets
-  });
-
-  tearDown(() async {
-    await sut.dispose();
-  });
-
-  test('buffer holds the first batch but not the whole library', () {
-    expect(sut.totalAssets, total);
-    expect(sut.hasRange(0, kTimelineAssetLoadBatchSize), isTrue);
-    expect(sut.hasRange(0, total), isFalse);
-  });
-
-  // #27118 / #20855 mechanism: drag-selecting from a low anchor while the grid
-  // auto-scrolls down slides the buffer forward to follow the finger. once the
-  // buffer offset passes the anchor, hasRange(anchor, ...) is false and
-  // _handleDragAssetEnter silently stops extending the selection.
-  test('anchor drops out of the buffer after the grid scrolls down', () async {
-    const anchor = 5;
-    expect(sut.hasRange(anchor, 100), isTrue);
-
-    // the grid loads a far-down range as it auto-scrolls during the drag
-    await sut.loadAssets(1500, 1);
-
-    const current = 1500;
-    const count = current - anchor + 1;
-    expect(sut.hasRange(anchor, 1), isFalse, reason: 'anchor is now below the buffer offset');
-    expect(sut.hasRange(anchor, count), isFalse, reason: 'the full drag range is no longer resident');
-    expect(() => sut.getAssets(anchor, count), throwsRangeError);
-  });
-
-  // the fix: getAssetsRange returns the whole drag range regardless of the
-  // buffer position, so the selection keeps extending while scrolling.
-  group('getAssetsRange', () {
-    test('returns a buffered range', () async {
-      final assets = await sut.getAssetsRange(0, 50);
-      expect(assets.length, 50);
-      expect(assets.first, all[0]);
-      expect(assets.last, all[49]);
-    });
-
-    test('returns a range wider than the buffer', () async {
-      final assets = await sut.getAssetsRange(0, total);
-      expect(assets.length, total);
-      expect(assets.first, all[0]);
-      expect(assets.last, all[total - 1]);
-    });
-
-    test('returns the anchor range after the buffer scrolled past the anchor', () async {
-      const anchor = 5;
-      await sut.loadAssets(1500, 1); // buffer slides forward, dropping the anchor
-      expect(sut.hasRange(anchor, 1), isFalse);
-
-      const current = 1500;
-      const count = current - anchor + 1;
-      final assets = await sut.getAssetsRange(anchor, count);
-      expect(assets.length, count);
-      expect(assets.first, all[anchor]);
-      expect(assets.last, all[current]);
-    });
-
-    test('clamps a range that runs past the end and ignores invalid input', () async {
-      final tail = await sut.getAssetsRange(total - 10, 100);
-      expect(tail.length, 10);
-      expect(await sut.getAssetsRange(-1, 10), isEmpty);
-      expect(await sut.getAssetsRange(0, 0), isEmpty);
-      expect(await sut.getAssetsRange(total, 10), isEmpty);
-    });
-  });
-}

pnpm-lock.yaml

@@ -786,8 +786,8 @@ importers:
         specifier: workspace:*
         version: link:../packages/sdk
       '@immich/ui':
-        specifier: ^0.81.1
-        version: 0.81.1(@sveltejs/kit@2.65.1(@opentelemetry/api@1.9.1)(@sveltejs/vite-plugin-svelte@7.1.2(svelte@5.56.3(@typescript-eslint/types@8.61.0))(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))(typescript@6.0.3)(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))
+        specifier: ^0.83.0
+        version: 0.83.0(@sveltejs/kit@2.65.1(@opentelemetry/api@1.9.1)(@sveltejs/vite-plugin-svelte@7.1.2(svelte@5.56.3(@typescript-eslint/types@8.61.0))(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))(typescript@6.0.3)(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))
       '@mapbox/mapbox-gl-rtl-text':
         specifier: 0.4.0
         version: 0.4.0
@@ -3250,8 +3250,8 @@ packages:
     resolution: {integrity: sha512-O1SJ+BbeFVsUTF4af1MfagJZM+lPgLjI8lQ3SZNjpo8SGJReSbUl2ii03OKuGni/G0yp2GnRLpOTNSHYGtVrcg==}
     hasBin: true
 
-  '@immich/ui@0.81.1':
-    resolution: {integrity: sha512-7g173hArs7OS5CfHUG+ZJVQp1iCvFZzBmm+f2uH1WChlFdcwty5DLilYrDBszWuPIvu8wTX2AXTneS/KYBCUxw==}
+  '@immich/ui@0.83.0':
+    resolution: {integrity: sha512-Xh3R3yhn8/Qyq8lGWIiVmturA+dHXtmW/h++AGb2UAwS/58qu7ssocO/HWIamaSpkgjPGotlWpPIpUJq1zh9FQ==}
     peerDependencies:
       '@sveltejs/kit': ^2.13.0
       svelte: ^5.0.0
@@ -16111,7 +16111,7 @@ snapshots:
       pg-connection-string: 2.13.0
       postgres: 3.4.9
 
-  '@immich/ui@0.81.1(@sveltejs/kit@2.65.1(@opentelemetry/api@1.9.1)(@sveltejs/vite-plugin-svelte@7.1.2(svelte@5.56.3(@typescript-eslint/types@8.61.0))(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))(typescript@6.0.3)(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))':
+  '@immich/ui@0.83.0(@sveltejs/kit@2.65.1(@opentelemetry/api@1.9.1)(@sveltejs/vite-plugin-svelte@7.1.2(svelte@5.56.3(@typescript-eslint/types@8.61.0))(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))(typescript@6.0.3)(vite@8.0.16(@types/node@24.13.2)(esbuild@0.28.1)(jiti@2.7.0)(sass@1.101.0)(terser@5.48.0)(tsx@4.22.4)(yaml@2.9.0)))(svelte@5.56.3(@typescript-eslint/types@8.61.0))':
     dependencies:
       '@internationalized/date': 3.12.2
       '@mdi/js': 7.4.47
@@ -21092,21 +21092,21 @@ snapshots:
       signal-exit: 3.0.7
       strip-final-newline: 2.0.0
 
-  exiftool-vendored.exe@13.59.0:
-    optional: true
+  exiftool-vendored.exe@13.59.0: {}
 
-  exiftool-vendored.pl@13.59.0: {}
+  exiftool-vendored.pl@13.59.0:
+    optional: true
 
   exiftool-vendored@35.21.0:
     dependencies:
       '@photostructure/tz-lookup': 11.5.0
       '@types/luxon': 3.7.1
       batch-cluster: 17.3.1
-      exiftool-vendored.pl: 13.59.0
+      exiftool-vendored.exe: 13.59.0
       he: 1.2.0
       luxon: 3.7.2
     optionalDependencies:
-      exiftool-vendored.exe: 13.59.0
+      exiftool-vendored.pl: 13.59.0
 
   expand-template@2.0.3:
     optional: true

pnpm-workspace.yaml

@@ -66,4 +66,4 @@ injectWorkspacePackages: true
 shamefullyHoist: false
 verifyDepsBeforeRun: install
 minimumReleaseAgeExclude:
-  - '@immich/ui@0.81.1'
+  - '@immich/ui@0.83.0'

web/package.json

@@ -27,7 +27,7 @@
     "@formatjs/icu-messageformat-parser": "^3.0.0",
     "@immich/justified-layout-wasm": "^0.4.3",
     "@immich/sdk": "workspace:*",
-    "@immich/ui": "^0.81.1",
+    "@immich/ui": "^0.83.0",
     "@mapbox/mapbox-gl-rtl-text": "0.4.0",
     "@mdi/js": "^7.4.47",
     "@noble/hashes": "^2.2.0",

web/src/lib/components/asset-viewer/AssetViewer.svelte

@@ -14,6 +14,7 @@
   import { authManager } from '$lib/managers/auth-manager.svelte';
   import { editManager, EditToolType } from '$lib/managers/edit/edit-manager.svelte';
   import { eventManager } from '$lib/managers/event-manager.svelte';
+  import type { TimelineAsset } from '$lib/managers/timeline-manager/types';
   import { getAssetActions } from '$lib/services/asset.service';
   import { faceManager } from '$lib/stores/face.svelte';
   import { ocrManager } from '$lib/stores/ocr.svelte';
@@ -23,6 +24,7 @@
   import type { OnUndoDelete } from '$lib/utils/actions';
   import { navigateToAsset } from '$lib/utils/asset-utils';
   import { handleError } from '$lib/utils/handle-error';
+  import { navigate } from '$lib/utils/navigation';
   import { InvocationTracker } from '$lib/utils/invocationTracker';
   import { SlideshowHistory } from '$lib/utils/slideshow-history';
   import { toTimelineAsset } from '$lib/utils/timeline-util';
@@ -149,6 +151,15 @@
     }
   };
 
+  const onAssetsUndoArchive = async (assets: TimelineAsset[]) => {
+    if (assets.length === 0) {
+      return;
+    }
+    const restoredAsset = assets[0];
+    await assetViewerManager.setAssetId(restoredAsset.id);
+    await navigate({ targetRoute: 'current', assetId: restoredAsset.id });
+  };
+
   onMount(() => {
     syncAssetViewerOpenClass(true);
     const slideshowStateUnsubscribe = slideshowState.subscribe((value) => {
@@ -475,7 +486,7 @@
 </script>
 
 <CommandPaletteDefaultProvider name={$t('assets')} actions={[Tag, TagPeople]} />
-<OnEvents {onAssetUpdate} />
+<OnEvents {onAssetUpdate} {onAssetsUndoArchive} />
 
 <svelte:document
   bind:fullscreenElement

web/src/lib/components/shared-components/map/Map.svelte

@@ -309,12 +309,12 @@
     untrack(() => map?.jumpTo({ center, zoom }));
   });
 
-  const onAssetsDelete = async () => {
+  const onAssetsChanged = async () => {
     mapMarkers = await loadMapMarkers();
   };
 </script>
 
-<OnEvents {onAssetsDelete} />
+<OnEvents onAssetsDelete={onAssetsChanged} onAssetsArchive={onAssetsChanged} onAssetsUnarchive={onAssetsChanged} />
 
 <!--  We handle style loading ourselves so we set style blank here -->
 <MapLibre

web/src/lib/managers/event-manager.svelte.ts

@@ -16,6 +16,7 @@ import type {
   UserAdminResponseDto,
   WorkflowResponseDto,
 } from '@immich/sdk';
+import type { TimelineAsset } from '$lib/managers/timeline-manager/types';
 import { BaseEventManager } from '$lib/utils/base-event-manager.svelte';
 import type { TreeNode } from '$lib/utils/tree-utils';
 
@@ -35,6 +36,8 @@ export type Events = {
 
   AssetUpdate: [AssetResponseDto];
   AssetsArchive: [string[]];
+  AssetsUnarchive: [TimelineAsset[]];
+  AssetsUndoArchive: [TimelineAsset[]];
   AssetsDelete: [string[]];
   AssetEditsApplied: [string];
   AssetsTag: [string[]];

web/src/lib/managers/timeline-manager/timeline-manager.svelte.ts

@@ -1,4 +1,4 @@
-import { AssetOrder, getAssetInfo, getTimeBuckets, AssetOrderBy, type AssetResponseDto } from '@immich/sdk';
+import { AssetOrder, AssetOrderBy, getAssetInfo, getTimeBuckets, type AssetResponseDto } from '@immich/sdk';
 import { clamp, isEqual } from 'lodash-es';
 import { SvelteDate, SvelteSet } from 'svelte/reactivity';
 import { VirtualScrollManager } from '$lib/managers/VirtualScrollManager/VirtualScrollManager.svelte';
@@ -114,7 +114,15 @@ export class TimelineManager extends VirtualScrollManager {
 
     this.#unsubscribes.push(
       eventManager.on({
-        AssetUpdate: (asset: AssetResponseDto) => this.#updateAssets([toTimelineAsset(asset)]),
+        AssetUpdate: (asset: AssetResponseDto) => {
+          const timelineAsset = toTimelineAsset(asset);
+          if (this.#options.albumId || this.#options.personId) {
+            this.#updateAssets([timelineAsset]);
+          } else {
+            this.upsertAssets([timelineAsset]);
+          }
+        },
+        AssetsUnarchive: (assets) => this.upsertAssets(assets),
       }),
     );
   }

web/src/lib/utils/asset-utils.ts

@@ -17,13 +17,14 @@ import {
   type StackResponseDto,
   type UserResponseDto,
 } from '@immich/sdk';
-import { toastManager } from '@immich/ui';
+import { toastManager, type ToastShow } from '@immich/ui';
 import { DateTime } from 'luxon';
 import { t } from 'svelte-i18n';
 import { get } from 'svelte/store';
 import type { AssetMultiSelectManager } from '$lib/managers/asset-multi-select-manager.svelte';
 import { authManager } from '$lib/managers/auth-manager.svelte';
 import { downloadManager } from '$lib/managers/download-manager.svelte';
+import { eventManager } from '$lib/managers/event-manager.svelte';
 import { TimelineManager } from '$lib/managers/timeline-manager/timeline-manager.svelte';
 import type { TimelineAsset } from '$lib/managers/timeline-manager/types';
 import { downloadBlob, downloadRequest, withError } from '$lib/utils';
@@ -31,6 +32,7 @@ import { getByteUnitString } from '$lib/utils/byte-units';
 import { getFormatter } from '$lib/utils/i18n';
 import { navigate } from '$lib/utils/navigation';
 import { asQueryString } from '$lib/utils/shared-links';
+import { toTimelineAsset } from '$lib/utils/timeline-util';
 import { handleError } from './handle-error';
 
 export const tagAssets = async ({
@@ -400,7 +402,12 @@ export const toggleArchive = async (asset: AssetResponseDto) => {
     });
 
     asset.isArchived = data.isArchived;
-    toastManager.primary(asset.isArchived ? $t(`added_to_archive`) : $t(`removed_from_archive`));
+    if (asset.isArchived) {
+      const timelineAsset = toTimelineAsset(asset);
+      showUndoArchiveToast($t('added_to_archive'), [timelineAsset]);
+    } else {
+      toastManager.primary($t('removed_from_archive'));
+    }
   } catch (error) {
     handleError(error, $t('errors.unable_to_add_remove_archive', { values: { archived: asset.isArchived } }));
   }
@@ -408,7 +415,46 @@ export const toggleArchive = async (asset: AssetResponseDto) => {
   return asset;
 };
 
-export const archiveAssets = async (assets: { id: string }[], visibility: AssetVisibility) => {
+const showUndoArchiveToast = (description: string, assets: TimelineAsset[]) => {
+  const $t = get(t);
+  const toast: ToastShow & { onClose?: () => void } = {
+    description,
+    button: (close) => ({
+      label: $t('undo'),
+      onclick: () => {
+        close();
+        void undoArchiveAssets(assets);
+      },
+    }),
+  };
+  toastManager.primary(toast);
+};
+
+const undoArchiveAssets = async (assets: TimelineAsset[]) => {
+  const $t = get(t);
+  try {
+    const ids = assets.map((a) => a.id);
+    if (ids.length > 0) {
+      await updateAssets({
+        assetBulkUpdateDto: {
+          ids,
+          visibility: AssetVisibility.Timeline,
+        },
+      });
+    }
+
+    for (const asset of assets) {
+      asset.visibility = AssetVisibility.Timeline;
+    }
+    eventManager.emit('AssetsUnarchive', assets);
+    eventManager.emit('AssetsUndoArchive', assets);
+    toastManager.success($t('unarchived_count', { values: { count: assets.length } }));
+  } catch (error) {
+    handleError(error, $t('errors.unable_to_archive_unarchive', { values: { archived: false } }));
+  }
+};
+
+export const archiveAssets = async (assets: TimelineAsset[], visibility: AssetVisibility) => {
   const ids = assets.map(({ id }) => id);
   const $t = get(t);
 
@@ -419,11 +465,11 @@ export const archiveAssets = async (assets: { id: string }[], visibility: AssetV
       });
     }
 
-    toastManager.primary(
-      visibility === AssetVisibility.Archive
-        ? $t('archived_count', { values: { count: ids.length } })
-        : $t('unarchived_count', { values: { count: ids.length } }),
-    );
+    if (visibility === AssetVisibility.Archive) {
+      showUndoArchiveToast($t('archived_count', { values: { count: ids.length } }), assets);
+    } else {
+      toastManager.primary($t('unarchived_count', { values: { count: ids.length } }));
+    }
   } catch (error) {
     handleError(
       error,

web/src/lib/utils/timeline-util.ts

@@ -165,7 +165,10 @@ export const toTimelineAsset = (unknownAsset: AssetResponseDto | TimelineAsset):
   const people = assetResponse.people?.map((person) => person.name) || [];
 
   const localDateTime = fromISODateTimeUTCToObject(assetResponse.localDateTime);
-  const fileCreatedAt = fromISODateTimeToObject(assetResponse.fileCreatedAt, assetResponse.exifInfo?.timeZone ?? 'UTC');
+  // Keep this consistent with the bucket loader (getTimes), which stores fileCreatedAt as UTC
+  // components. The timeline sorts assets within a day by fileCreatedAt, so a mismatched
+  // representation here would place re-inserted assets (e.g. undo archive) in the wrong spot.
+  const fileCreatedAt = fromISODateTimeUTCToObject(assetResponse.fileCreatedAt);
   const createdAt = fromISODateTimeUTCToObject(assetResponse.createdAt);
 
   return {

web/src/routes/(user)/people/[personId]/[[photos=photos]]/[[assetId=id]]/+page.svelte

@@ -329,6 +329,7 @@
   onPersonAssetDelete={handlePersonAssetDelete}
   onAssetsDelete={updateAssetCount}
   onAssetsArchive={updateAssetCount}
+  onAssetsUnarchive={updateAssetCount}
 />
 
 <main