refactor(web): extract asset viewer logic from Timeline into TimelineAssetViewer component

- Extracted asset viewer navigation and action handling logic from Timeline.svelte into a dedicated TimelineAssetViewer component
- Reduces Timeline.svelte complexity by ~150 lines and improves separation of concerns
- No functional changes - purely a refactoring to improve code organization

## Changes
- Created new TimelineAssetViewer.svelte component containing all asset viewer-related logic
- Moved handlePrevious, handleNext, handleRandom, handleClose, handlePreAction, and handleAction methods
- Timeline.svelte now only passes required props to the new component
- Maintained all existing functionality including navigation, asset actions, and stack management

web/src/lib/components/timeline/Scrubber.svelte

@@ -3,7 +3,7 @@
   import type { ScrubberMonth } from '$lib/managers/timeline-manager/types';
   import { mobileDevice } from '$lib/stores/mobile-device.svelte';
   import { getTabbable } from '$lib/utils/focus-util';
-  import { type ScrubberListener } from '$lib/utils/timeline-util';
+  import { type ScrubberListener, type TimelineYearMonth } from '$lib/utils/timeline-util';
   import { Icon } from '@immich/ui';
   import { mdiPlay } from '@mdi/js';
   import { clamp } from 'lodash-es';
@@ -11,18 +11,31 @@
   import { fade, fly } from 'svelte/transition';
 
   interface Props {
+    /** Offset from the top of the timeline (e.g., for headers) */
     timelineTopOffset?: number;
+    /** Offset from the bottom of the timeline (e.g., for footers) */
     timelineBottomOffset?: number;
+    /** Total height of the scrubber component */
     height?: number;
+    /** Timeline manager instance that controls the timeline state */
     timelineManager: TimelineManager;
-    scrubOverallPercent?: number;
-    scrubberMonthPercent?: number;
-    scrubberMonth?: { year: number; month: number };
-    leadout?: boolean;
+    /** Overall scroll percentage through the entire timeline (0-1), used when no specific month is targeted */
+    timelineScrollPercent?: number;
+    /** The percentage of scroll through the month that is currently intersecting the top boundary of the viewport */
+    viewportTopMonthScrollPercent?: number;
+    /** The year/month of the timeline month at the top of the viewport */
+    viewportTopMonth?: TimelineYearMonth;
+    /** Indicates whether the viewport is currently in the lead-out section (after all months) */
+    isInLeadOutSection?: boolean;
+    /** Width of the scrubber component in pixels (bindable for parent component margin adjustments) */
     scrubberWidth?: number;
+    /** Callback fired when user interacts with the scrubber to navigate */
     onScrub?: ScrubberListener;
+    /** Callback fired when keyboard events occur on the scrubber */
     onScrubKeyDown?: (event: KeyboardEvent, element: HTMLElement) => void;
+    /** Callback fired when scrubbing starts */
     startScrub?: ScrubberListener;
+    /** Callback fired when scrubbing stops */
     stopScrub?: ScrubberListener;
   }
 
@@ -31,10 +44,10 @@
     timelineBottomOffset = 0,
     height = 0,
     timelineManager,
-    scrubOverallPercent = 0,
-    scrubberMonthPercent = 0,
-    scrubberMonth = undefined,
-    leadout = false,
+    timelineScrollPercent = 0,
+    viewportTopMonthScrollPercent = 0,
+    viewportTopMonth = undefined,
+    isInLeadOutSection = false,
     onScrub = undefined,
     onScrubKeyDown = undefined,
     startScrub = undefined,
@@ -100,7 +113,7 @@
         offset += scrubberMonthPercent * relativeBottomOffset;
       }
       return offset;
-    } else if (leadout) {
+    } else if (isInLeadOutSection) {
       let offset = relativeTopOffset;
       for (const segment of segments) {
         offset += segment.height;
@@ -111,7 +124,9 @@
       return scrubOverallPercent * (height - (PADDING_TOP + PADDING_BOTTOM));
     }
   };
-  let scrollY = $derived(toScrollFromMonthGroupPercentage(scrubberMonth, scrubberMonthPercent, scrubOverallPercent));
+  let scrollY = $derived(
+    toScrollFromMonthGroupPercentage(viewportTopMonth, viewportTopMonthScrollPercent, timelineScrollPercent),
+  );
   let timelineFullHeight = $derived(timelineManager.scrubberTimelineHeight + timelineTopOffset + timelineBottomOffset);
   let relativeTopOffset = $derived(toScrollY(timelineTopOffset / timelineFullHeight));
   let relativeBottomOffset = $derived(toScrollY(timelineBottomOffset / timelineFullHeight));
@@ -295,12 +310,24 @@
 
     const scrollPercent = toTimelineY(hoverY);
     if (wasDragging === false && isDragging) {
-      void startScrub?.(segmentDate!, scrollPercent, monthGroupPercentY);
-      void onScrub?.(segmentDate!, scrollPercent, monthGroupPercentY);
+      void startScrub?.({
+        scrubberMonth: segmentDate!,
+        overallScrollPercent: scrollPercent,
+        scrubberMonthScrollPercent: monthGroupPercentY,
+      });
+      void onScrub?.({
+        scrubberMonth: segmentDate!,
+        overallScrollPercent: scrollPercent,
+        scrubberMonthScrollPercent: monthGroupPercentY,
+      });
     }
 
     if (wasDragging && !isDragging) {
-      void stopScrub?.(segmentDate!, scrollPercent, monthGroupPercentY);
+      void stopScrub?.({
+        scrubberMonth: segmentDate!,
+        overallScrollPercent: scrollPercent,
+        scrubberMonthScrollPercent: monthGroupPercentY,
+      });
       return;
     }
 
@@ -308,7 +335,11 @@
       return;
     }
 
-    void onScrub?.(segmentDate!, scrollPercent, monthGroupPercentY);
+    void onScrub?.({
+      scrubberMonth: segmentDate!,
+      overallScrollPercent: scrollPercent,
+      scrubberMonthScrollPercent: monthGroupPercentY,
+    });
   };
   /* eslint-disable tscompat/tscompat */
   const getTouch = (event: TouchEvent) => {
@@ -412,7 +443,11 @@
       }
       if (next) {
         event.preventDefault();
-        void onScrub?.({ year: next.year, month: next.month }, -1, 0);
+        void onScrub?.({
+          scrubberMonth: { year: next.year, month: next.month },
+          overallScrollPercent: -1,
+          scrubberMonthScrollPercent: 0,
+        });
         return true;
       }
     }
@@ -422,7 +457,11 @@
         const next = segments[idx + 1];
         if (next) {
           event.preventDefault();
-          void onScrub?.({ year: next.year, month: next.month }, -1, 0);
+          void onScrub?.({
+            scrubberMonth: { year: next.year, month: next.month },
+            overallScrollPercent: -1,
+            scrubberMonthScrollPercent: 0,
+          });
           return true;
         }
       }

web/src/lib/components/timeline/Timeline.svelte

@@ -1,45 +1,29 @@
 <script lang="ts">
-  import { afterNavigate, beforeNavigate, goto } from '$app/navigation';
+  import { afterNavigate, beforeNavigate } from '$app/navigation';
   import { page } from '$app/stores';
   import { resizeObserver, type OnResizeCallback } from '$lib/actions/resize-observer';
-  import { shortcuts, type ShortcutOptions } from '$lib/actions/shortcut';
-  import type { Action } from '$lib/components/asset-viewer/actions/action';
-  import type { AbsoluteResult, RelativeResult } from '$lib/components/shared-components/change-date.svelte';
-  import ChangeDate from '$lib/components/shared-components/change-date.svelte';
   import Scrubber from '$lib/components/timeline/Scrubber.svelte';
-  import {
-    setFocusToAsset as setFocusAssetInit,
-    setFocusTo as setFocusToInit,
-  } from '$lib/components/timeline/actions/focus-actions';
-  import { AppRoute, AssetAction } from '$lib/constants';
+  import TimelineAssetViewer from '$lib/components/timeline/TimelineAssetViewer.svelte';
+  import TimelineKeyboardActions from '$lib/components/timeline/actions/TimelineKeyboardActions.svelte';
+  import { AssetAction } from '$lib/constants';
   import HotModuleReload from '$lib/elements/HotModuleReload.svelte';
   import Portal from '$lib/elements/Portal.svelte';
   import Skeleton from '$lib/elements/Skeleton.svelte';
-  import { authManager } from '$lib/managers/auth-manager.svelte';
   import type { DayGroup } from '$lib/managers/timeline-manager/day-group.svelte';
   import type { MonthGroup } from '$lib/managers/timeline-manager/month-group.svelte';
   import { TimelineManager } from '$lib/managers/timeline-manager/timeline-manager.svelte';
   import type { TimelineAsset } from '$lib/managers/timeline-manager/types';
   import { assetsSnapshot } from '$lib/managers/timeline-manager/utils.svelte';
-  import ShortcutsModal from '$lib/modals/ShortcutsModal.svelte';
   import type { AssetInteraction } from '$lib/stores/asset-interaction.svelte';
   import { assetViewingStore } from '$lib/stores/asset-viewing.store';
   import { isSelectingAllAssets } from '$lib/stores/assets-store.svelte';
   import { mobileDevice } from '$lib/stores/mobile-device.svelte';
-  import { showDeleteModal } from '$lib/stores/preferences.store';
-  import { searchStore } from '$lib/stores/search.svelte';
-  import { featureFlags } from '$lib/stores/server-config.store';
-  import { handlePromiseError } from '$lib/utils';
-  import { deleteAssets, updateStackedAssetInTimeline, updateUnstackedAssetInTimeline } from '$lib/utils/actions';
-  import { archiveAssets, cancelMultiselect, selectAllAssets, stackAssets } from '$lib/utils/asset-utils';
   import { navigate } from '$lib/utils/navigation';
-  import { getTimes, toTimelineAsset, type ScrubberListener, type TimelineYearMonth } from '$lib/utils/timeline-util';
-  import { AssetVisibility, getAssetInfo, type AlbumResponseDto, type PersonResponseDto } from '@immich/sdk';
-  import { modalManager } from '@immich/ui';
+  import { getTimes, type ScrubberListener, type TimelineYearMonth } from '$lib/utils/timeline-util';
+  import { type AlbumResponseDto, type PersonResponseDto } from '@immich/sdk';
   import { DateTime } from 'luxon';
   import { onMount, type Snippet } from 'svelte';
   import type { UpdatePayload } from 'vite';
-  import DeleteAssetDialog from '../photos-page/delete-asset-dialog.svelte';
   import TimelineDateGroup from './TimelineDateGroup.svelte';
 
   interface Props {
@@ -103,22 +87,27 @@
     onThumbnailClick,
   }: Props = $props();
 
-  let { isViewing: showAssetViewer, asset: viewingAsset, preloadAssets, gridScrollTarget, mutex } = assetViewingStore;
+  let { isViewing: showAssetViewer, asset: viewingAsset, gridScrollTarget } = assetViewingStore;
 
   let element: HTMLElement | undefined = $state();
 
   let timelineElement: HTMLElement | undefined = $state();
   let showSkeleton = $state(true);
-  let isShowSelectDate = $state(false);
-  let scrubberMonthPercent = $state(0);
-  let scrubberMonth: { year: number; month: number } | undefined = $state(undefined);
-  let scrubOverallPercent: number = $state(0);
+  // The percentage of scroll through the month that is currently intersecting the top boundary of the viewport.
+  // Note: There may be multiple months visible within the viewport at any given time.
+  let viewportTopMonthScrollPercent = $state(0);
+  // The timeline month intersecting the top position of the viewport
+  let viewportTopMonth: { year: number; month: number } | undefined = $state(undefined);
+  // Overall scroll percentage through the entire timeline (0-1)
+  let timelineScrollPercent: number = $state(0);
   let scrubberWidth = $state(0);
 
   // 60 is the bottom spacer element at 60px
   let bottomSectionHeight = 60;
-  let leadout = $state(false);
+  // Indicates whether the viewport is currently in the lead-out section (after all months)
+  let isInLeadOutSection = $state(false);
 
+  const isEmpty = $derived(timelineManager.isInitialized && timelineManager.months.length === 0);
   const maxMd = $derived(mobileDevice.maxMd);
   const usingMobileDevice = $derived(mobileDevice.pointerCoarse);
 
@@ -301,20 +290,19 @@
     scrollTop(scrollToTop);
   };
 
-  // note: don't throttle, debounch, or otherwise make this function async - it causes flicker
-  const onScrub: ScrubberListener = (
-    scrubMonth: { year: number; month: number },
-    overallScrollPercent: number,
-    scrubberMonthScrollPercent: number,
-  ) => {
-    if (!scrubMonth || timelineManager.timelineHeight < timelineManager.viewportHeight * 2) {
+  // note: don't throttle, debounce, or otherwise make this function async - it causes flicker
+  // this function scrolls the timeline to the specified month group and offset, based on scrubber interaction
+  const onScrub: ScrubberListener = (scrubberData) => {
+    const { scrubberMonth, overallScrollPercent, scrubberMonthScrollPercent } = scrubberData;
+
+    if (!scrubberMonth || timelineManager.timelineHeight < timelineManager.viewportHeight * 2) {
       // edge case - scroll limited due to size of content, must adjust - use use the overall percent instead
       const maxScroll = getMaxScroll();
       const offset = maxScroll * overallScrollPercent;
       scrollTop(offset);
     } else {
       const monthGroup = timelineManager.months.find(
-        ({ yearMonth: { year, month } }) => year === scrubMonth.year && month === scrubMonth.month,
+        ({ yearMonth: { year, month } }) => year === scrubberMonth.year && month === scrubberMonth.month,
       );
       if (!monthGroup) {
         return;
@@ -325,7 +313,7 @@
 
   // note: don't throttle, debounch, or otherwise make this function async - it causes flicker
   const handleTimelineScroll = () => {
-    leadout = false;
+    isInLeadOutSection = false;
 
     if (!element) {
       return;
@@ -334,19 +322,19 @@
     if (timelineManager.timelineHeight < timelineManager.viewportHeight * 2) {
       // edge case - scroll limited due to size of content, must adjust -  use the overall percent instead
       const maxScroll = getMaxScroll();
-      scrubOverallPercent = Math.min(1, element.scrollTop / maxScroll);
+      timelineScrollPercent = Math.min(1, element.scrollTop / maxScroll);
 
-      scrubberMonth = undefined;
-      scrubberMonthPercent = 0;
+      viewportTopMonth = undefined;
+      viewportTopMonthScrollPercent = 0;
     } else {
       let top = element.scrollTop;
       if (top < timelineManager.topSectionHeight) {
         // in the lead-in area
-        scrubberMonth = undefined;
-        scrubberMonthPercent = 0;
+        viewportTopMonth = undefined;
+        viewportTopMonthScrollPercent = 0;
         const maxScroll = getMaxScroll();
 
-        scrubOverallPercent = Math.min(1, element.scrollTop / maxScroll);
+        timelineScrollPercent = Math.min(1, element.scrollTop / maxScroll);
         return;
       }
 
@@ -371,15 +359,15 @@
         let next = top - monthGroupHeight * maxScrollPercent;
         // instead of checking for < 0, add a little wiggle room for subpixel resolution
         if (next < -1 && monthGroup) {
-          scrubberMonth = monthGroup;
+          viewportTopMonth = monthGroup;
 
           // allowing next to be at least 1 may cause percent to go negative, so ensure positive percentage
-          scrubberMonthPercent = Math.max(0, top / (monthGroupHeight * maxScrollPercent));
+          viewportTopMonthScrollPercent = Math.max(0, top / (monthGroupHeight * maxScrollPercent));
 
           // compensate for lost precision/rounding errors advance to the next bucket, if present
-          if (scrubberMonthPercent > 0.9999 && i + 1 < monthsLength - 1) {
-            scrubberMonth = timelineManager.months[i + 1].yearMonth;
-            scrubberMonthPercent = 0;
+          if (viewportTopMonthScrollPercent > 0.9999 && i + 1 < monthsLength - 1) {
+            viewportTopMonth = timelineManager.months[i + 1].yearMonth;
+            viewportTopMonthScrollPercent = 0;
           }
 
           found = true;
@@ -388,200 +376,25 @@
         top = next;
       }
       if (!found) {
-        leadout = true;
-        scrubberMonth = undefined;
-        scrubberMonthPercent = 0;
-        scrubOverallPercent = 1;
+        isInLeadOutSection = true;
+        viewportTopMonth = undefined;
+        viewportTopMonthScrollPercent = 0;
+        timelineScrollPercent = 1;
       }
     }
   };
 
-  const trashOrDelete = async (force: boolean = false) => {
-    isShowDeleteConfirmation = false;
-    await deleteAssets(
-      !(isTrashEnabled && !force),
-      (assetIds) => timelineManager.removeAssets(assetIds),
-      assetInteraction.selectedAssets,
-      !isTrashEnabled || force ? undefined : (assets) => timelineManager.addAssets(assets),
-    );
-    assetInteraction.clearMultiselect();
-  };
-
-  const onDelete = () => {
-    const hasTrashedAsset = assetInteraction.selectedAssets.some((asset) => asset.isTrashed);
-
-    if ($showDeleteModal && (!isTrashEnabled || hasTrashedAsset)) {
-      isShowDeleteConfirmation = true;
-      return;
-    }
-    handlePromiseError(trashOrDelete(hasTrashedAsset));
-  };
-
-  const onForceDelete = () => {
-    if ($showDeleteModal) {
-      isShowDeleteConfirmation = true;
-      return;
-    }
-    handlePromiseError(trashOrDelete(true));
-  };
-
-  const onStackAssets = async () => {
-    const result = await stackAssets(assetInteraction.selectedAssets);
-
-    updateStackedAssetInTimeline(timelineManager, result);
-
-    onEscape();
-  };
-
-  const toggleArchive = async () => {
-    const visibility = assetInteraction.isAllArchived ? AssetVisibility.Timeline : AssetVisibility.Archive;
-    const ids = await archiveAssets(assetInteraction.selectedAssets, visibility);
-    timelineManager.updateAssetOperation(ids, (asset) => {
-      asset.visibility = visibility;
-      return { remove: false };
-    });
-    deselectAllAssets();
-  };
-
   const handleSelectAsset = (asset: TimelineAsset) => {
     if (!timelineManager.albumAssets.has(asset.id)) {
       assetInteraction.selectAsset(asset);
     }
   };
 
-  const handlePrevious = async () => {
-    const release = await mutex.acquire();
-    const laterAsset = await timelineManager.getLaterAsset($viewingAsset);
-
-    if (laterAsset) {
-      const preloadAsset = await timelineManager.getLaterAsset(laterAsset);
-      const asset = await getAssetInfo({ ...authManager.params, id: laterAsset.id });
-      assetViewingStore.setAsset(asset, preloadAsset ? [preloadAsset] : []);
-      await navigate({ targetRoute: 'current', assetId: laterAsset.id });
-    }
-
-    release();
-    return !!laterAsset;
-  };
-
-  const handleNext = async () => {
-    const release = await mutex.acquire();
-    const earlierAsset = await timelineManager.getEarlierAsset($viewingAsset);
-
-    if (earlierAsset) {
-      const preloadAsset = await timelineManager.getEarlierAsset(earlierAsset);
-      const asset = await getAssetInfo({ ...authManager.params, id: earlierAsset.id });
-      assetViewingStore.setAsset(asset, preloadAsset ? [preloadAsset] : []);
-      await navigate({ targetRoute: 'current', assetId: earlierAsset.id });
-    }
-
-    release();
-    return !!earlierAsset;
-  };
-
-  const handleRandom = async () => {
-    const randomAsset = await timelineManager.getRandomAsset();
-
-    if (randomAsset) {
-      const asset = await getAssetInfo({ ...authManager.params, id: randomAsset.id });
-      assetViewingStore.setAsset(asset);
-      await navigate({ targetRoute: 'current', assetId: randomAsset.id });
-      return asset;
-    }
-  };
-
-  const handleClose = async (asset: { id: string }) => {
-    assetViewingStore.showAssetViewer(false);
-    showSkeleton = true;
-    $gridScrollTarget = { at: asset.id };
-    await navigate({ targetRoute: 'current', assetId: null, assetGridRouteSearchParams: $gridScrollTarget });
-  };
-
-  const handlePreAction = async (action: Action) => {
-    switch (action.type) {
-      case removeAction:
-      case AssetAction.TRASH:
-      case AssetAction.RESTORE:
-      case AssetAction.DELETE:
-      case AssetAction.ARCHIVE:
-      case AssetAction.SET_VISIBILITY_LOCKED:
-      case AssetAction.SET_VISIBILITY_TIMELINE: {
-        // find the next asset to show or close the viewer
-        // eslint-disable-next-line @typescript-eslint/no-unused-expressions
-        (await handleNext()) || (await handlePrevious()) || (await handleClose(action.asset));
-
-        // delete after find the next one
-        timelineManager.removeAssets([action.asset.id]);
-        break;
-      }
-    }
-  };
-  const handleAction = (action: Action) => {
-    switch (action.type) {
-      case AssetAction.ARCHIVE:
-      case AssetAction.UNARCHIVE:
-      case AssetAction.FAVORITE:
-      case AssetAction.UNFAVORITE: {
-        timelineManager.updateAssets([action.asset]);
-        break;
-      }
-
-      case AssetAction.ADD: {
-        timelineManager.addAssets([action.asset]);
-        break;
-      }
-
-      case AssetAction.UNSTACK: {
-        updateUnstackedAssetInTimeline(timelineManager, action.assets);
-        break;
-      }
-      case AssetAction.REMOVE_ASSET_FROM_STACK: {
-        timelineManager.addAssets([toTimelineAsset(action.asset)]);
-        if (action.stack) {
-          //Have to unstack then restack assets in timeline in order to update the stack count in the timeline.
-          updateUnstackedAssetInTimeline(
-            timelineManager,
-            action.stack.assets.map((asset) => toTimelineAsset(asset)),
-          );
-          updateStackedAssetInTimeline(timelineManager, {
-            stack: action.stack,
-            toDeleteIds: action.stack.assets
-              .filter((asset) => asset.id !== action.stack?.primaryAssetId)
-              .map((asset) => asset.id),
-          });
-        }
-        break;
-      }
-      case AssetAction.SET_STACK_PRIMARY_ASSET: {
-        //Have to unstack then restack assets in timeline in order for the currently removed new primary asset to be made visible.
-        updateUnstackedAssetInTimeline(
-          timelineManager,
-          action.stack.assets.map((asset) => toTimelineAsset(asset)),
-        );
-        updateStackedAssetInTimeline(timelineManager, {
-          stack: action.stack,
-          toDeleteIds: action.stack.assets
-            .filter((asset) => asset.id !== action.stack.primaryAssetId)
-            .map((asset) => asset.id),
-        });
-        break;
-      }
-    }
-  };
-
   let lastAssetMouseEvent: TimelineAsset | null = $state(null);
 
   let shiftKeyIsDown = $state(false);
 
-  const deselectAllAssets = () => {
-    cancelMultiselect(assetInteraction);
-  };
-
   const onKeyDown = (event: KeyboardEvent) => {
-    if (searchStore.isSearchEnabled) {
-      return;
-    }
-
     if (event.key === 'Shift') {
       event.preventDefault();
       shiftKeyIsDown = true;
@@ -589,16 +402,11 @@
   };
 
   const onKeyUp = (event: KeyboardEvent) => {
-    if (searchStore.isSearchEnabled) {
-      return;
-    }
-
     if (event.key === 'Shift') {
       event.preventDefault();
       shiftKeyIsDown = false;
     }
   };
-
   const handleSelectAssetCandidates = (asset: TimelineAsset | null) => {
     if (asset) {
       void selectAssetCandidates(asset);
@@ -724,72 +532,6 @@
     assetInteraction.setAssetSelectionCandidates(assets);
   };
 
-  const onSelectStart = (e: Event) => {
-    if (assetInteraction.selectionActive && shiftKeyIsDown) {
-      e.preventDefault();
-    }
-  };
-
-  let isTrashEnabled = $derived($featureFlags.loaded && $featureFlags.trash);
-  let isEmpty = $derived(timelineManager.isInitialized && timelineManager.months.length === 0);
-  let idsSelectedAssets = $derived(assetInteraction.selectedAssets.map(({ id }) => id));
-  let isShortcutModalOpen = false;
-
-  const handleOpenShortcutModal = async () => {
-    if (isShortcutModalOpen) {
-      return;
-    }
-
-    isShortcutModalOpen = true;
-    await modalManager.show(ShortcutsModal, {});
-    isShortcutModalOpen = false;
-  };
-
-  $effect(() => {
-    if (isEmpty) {
-      assetInteraction.clearMultiselect();
-    }
-  });
-
-  const setFocusTo = setFocusToInit.bind(undefined, scrollToAsset, timelineManager);
-  const setFocusAsset = setFocusAssetInit.bind(undefined, scrollToAsset);
-
-  let shortcutList = $derived(
-    (() => {
-      if (searchStore.isSearchEnabled || $showAssetViewer) {
-        return [];
-      }
-
-      const shortcuts: ShortcutOptions[] = [
-        { shortcut: { key: 'Escape' }, onShortcut: onEscape },
-        { shortcut: { key: '?', shift: true }, onShortcut: handleOpenShortcutModal },
-        { shortcut: { key: '/' }, onShortcut: () => goto(AppRoute.EXPLORE) },
-        { shortcut: { key: 'A', ctrl: true }, onShortcut: () => selectAllAssets(timelineManager, assetInteraction) },
-        { shortcut: { key: 'ArrowRight' }, onShortcut: () => setFocusTo('earlier', 'asset') },
-        { shortcut: { key: 'ArrowLeft' }, onShortcut: () => setFocusTo('later', 'asset') },
-        { shortcut: { key: 'D' }, onShortcut: () => setFocusTo('earlier', 'day') },
-        { shortcut: { key: 'D', shift: true }, onShortcut: () => setFocusTo('later', 'day') },
-        { shortcut: { key: 'M' }, onShortcut: () => setFocusTo('earlier', 'month') },
-        { shortcut: { key: 'M', shift: true }, onShortcut: () => setFocusTo('later', 'month') },
-        { shortcut: { key: 'Y' }, onShortcut: () => setFocusTo('earlier', 'year') },
-        { shortcut: { key: 'Y', shift: true }, onShortcut: () => setFocusTo('later', 'year') },
-        { shortcut: { key: 'G' }, onShortcut: () => (isShowSelectDate = true) },
-      ];
-
-      if (assetInteraction.selectionActive) {
-        shortcuts.push(
-          { shortcut: { key: 'Delete' }, onShortcut: onDelete },
-          { shortcut: { key: 'Delete', shift: true }, onShortcut: onForceDelete },
-          { shortcut: { key: 'D', ctrl: true }, onShortcut: () => deselectAllAssets() },
-          { shortcut: { key: 's' }, onShortcut: () => onStackAssets() },
-          { shortcut: { key: 'a', shift: true }, onShortcut: toggleArchive },
-        );
-      }
-
-      return shortcuts;
-    })(),
-  );
-
   $effect(() => {
     if (!lastAssetMouseEvent) {
       assetInteraction.clearAssetSelectionCandidates();
@@ -816,37 +558,17 @@
   });
 </script>
 
-<svelte:document onkeydown={onKeyDown} onkeyup={onKeyUp} onselectstart={onSelectStart} use:shortcuts={shortcutList} />
+<svelte:document onkeydown={onKeyDown} onkeyup={onKeyUp} />
 
 <HotModuleReload onAfterUpdate={handleAfterUpdate} onBeforeUpdate={handleBeforeUpdate} />
 
-{#if isShowDeleteConfirmation}
-  <DeleteAssetDialog
-    size={idsSelectedAssets.length}
-    onCancel={() => (isShowDeleteConfirmation = false)}
-    onConfirm={() => handlePromiseError(trashOrDelete(true))}
-  />
-{/if}
-
-{#if isShowSelectDate}
-  <ChangeDate
-    title="Navigate to Time"
-    initialDate={DateTime.now()}
-    timezoneInput={false}
-    onConfirm={async (dateString: AbsoluteResult | RelativeResult) => {
-      isShowSelectDate = false;
-      if (dateString.mode == 'absolute') {
-        const asset = await timelineManager.getClosestAssetToDate(
-          (DateTime.fromISO(dateString.date) as DateTime<true>).toObject(),
-        );
-        if (asset) {
-          setFocusAsset(asset);
-        }
-      }
-    }}
-    onCancel={() => (isShowSelectDate = false)}
-  />
-{/if}
+<TimelineKeyboardActions
+  scrollToAsset={(asset) => scrollToAsset(asset) ?? false}
+  {timelineManager}
+  {assetInteraction}
+  bind:isShowDeleteConfirmation
+  {onEscape}
+/>
 
 {#if timelineManager.months.length > 0}
   <Scrubber
@@ -854,10 +576,10 @@
     height={timelineManager.viewportHeight}
     timelineTopOffset={timelineManager.topSectionHeight}
     timelineBottomOffset={bottomSectionHeight}
-    {leadout}
-    {scrubOverallPercent}
-    {scrubberMonthPercent}
-    {scrubberMonth}
+    {isInLeadOutSection}
+    {timelineScrollPercent}
+    {viewportTopMonthScrollPercent}
+    {viewportTopMonth}
     {onScrub}
     bind:scrubberWidth
     onScrubKeyDown={(evt) => {
@@ -964,22 +686,7 @@
 
 <Portal target="body">
   {#if $showAssetViewer}
-    {#await import('../asset-viewer/asset-viewer.svelte') then { default: AssetViewer }}
-      <AssetViewer
-        {withStacked}
-        asset={$viewingAsset}
-        preloadAssets={$preloadAssets}
-        {isShared}
-        {album}
-        {person}
-        preAction={handlePreAction}
-        onAction={handleAction}
-        onPrevious={handlePrevious}
-        onNext={handleNext}
-        onRandom={handleRandom}
-        onClose={handleClose}
-      />
-    {/await}
+    <TimelineAssetViewer bind:showSkeleton {timelineManager} {removeAction} {withStacked} {isShared} {album} {person} />
   {/if}
 </Portal>
 

web/src/lib/components/timeline/TimelineAssetViewer.svelte

@@ -0,0 +1,177 @@
+<script lang="ts">
+  import type { Action } from '$lib/components/asset-viewer/actions/action';
+  import { AssetAction } from '$lib/constants';
+  import { authManager } from '$lib/managers/auth-manager.svelte';
+  import { TimelineManager } from '$lib/managers/timeline-manager/timeline-manager.svelte';
+  import { assetViewingStore } from '$lib/stores/asset-viewing.store';
+  import { updateStackedAssetInTimeline, updateUnstackedAssetInTimeline } from '$lib/utils/actions';
+  import { navigate } from '$lib/utils/navigation';
+  import { toTimelineAsset } from '$lib/utils/timeline-util';
+  import { getAssetInfo, type AlbumResponseDto, type PersonResponseDto } from '@immich/sdk';
+
+  let { asset: viewingAsset, gridScrollTarget, mutex, preloadAssets } = assetViewingStore;
+
+  interface Props {
+    timelineManager: TimelineManager;
+    showSkeleton: boolean;
+    withStacked?: boolean;
+    isShared?: boolean;
+    album?: AlbumResponseDto | null;
+    person?: PersonResponseDto | null;
+
+    removeAction?:
+      | AssetAction.UNARCHIVE
+      | AssetAction.ARCHIVE
+      | AssetAction.FAVORITE
+      | AssetAction.UNFAVORITE
+      | AssetAction.SET_VISIBILITY_TIMELINE
+      | null;
+  }
+
+  let {
+    timelineManager,
+    showSkeleton = $bindable(false),
+    removeAction,
+    withStacked = false,
+    isShared = false,
+    album = null,
+    person = null,
+  }: Props = $props();
+
+  const handlePrevious = async () => {
+    const release = await mutex.acquire();
+    const laterAsset = await timelineManager.getLaterAsset($viewingAsset);
+
+    if (laterAsset) {
+      const preloadAsset = await timelineManager.getLaterAsset(laterAsset);
+      const asset = await getAssetInfo({ ...authManager.params, id: laterAsset.id });
+      assetViewingStore.setAsset(asset, preloadAsset ? [preloadAsset] : []);
+      await navigate({ targetRoute: 'current', assetId: laterAsset.id });
+    }
+
+    release();
+    return !!laterAsset;
+  };
+
+  const handleNext = async () => {
+    const release = await mutex.acquire();
+    const earlierAsset = await timelineManager.getEarlierAsset($viewingAsset);
+
+    if (earlierAsset) {
+      const preloadAsset = await timelineManager.getEarlierAsset(earlierAsset);
+      const asset = await getAssetInfo({ ...authManager.params, id: earlierAsset.id });
+      assetViewingStore.setAsset(asset, preloadAsset ? [preloadAsset] : []);
+      await navigate({ targetRoute: 'current', assetId: earlierAsset.id });
+    }
+
+    release();
+    return !!earlierAsset;
+  };
+
+  const handleRandom = async () => {
+    const randomAsset = await timelineManager.getRandomAsset();
+
+    if (randomAsset) {
+      const asset = await getAssetInfo({ ...authManager.params, id: randomAsset.id });
+      assetViewingStore.setAsset(asset);
+      await navigate({ targetRoute: 'current', assetId: randomAsset.id });
+      return asset;
+    }
+  };
+
+  const handleClose = async (asset: { id: string }) => {
+    assetViewingStore.showAssetViewer(false);
+    showSkeleton = true;
+    $gridScrollTarget = { at: asset.id };
+    await navigate({ targetRoute: 'current', assetId: null, assetGridRouteSearchParams: $gridScrollTarget });
+  };
+
+  const handlePreAction = async (action: Action) => {
+    switch (action.type) {
+      case removeAction:
+      case AssetAction.TRASH:
+      case AssetAction.RESTORE:
+      case AssetAction.DELETE:
+      case AssetAction.ARCHIVE:
+      case AssetAction.SET_VISIBILITY_LOCKED:
+      case AssetAction.SET_VISIBILITY_TIMELINE: {
+        // find the next asset to show or close the viewer
+        // eslint-disable-next-line @typescript-eslint/no-unused-expressions
+        (await handleNext()) || (await handlePrevious()) || (await handleClose(action.asset));
+
+        // delete after find the next one
+        timelineManager.removeAssets([action.asset.id]);
+        break;
+      }
+    }
+  };
+  const handleAction = (action: Action) => {
+    switch (action.type) {
+      case AssetAction.ARCHIVE:
+      case AssetAction.UNARCHIVE:
+      case AssetAction.FAVORITE:
+      case AssetAction.UNFAVORITE: {
+        timelineManager.updateAssets([action.asset]);
+        break;
+      }
+
+      case AssetAction.ADD: {
+        timelineManager.addAssets([action.asset]);
+        break;
+      }
+
+      case AssetAction.UNSTACK: {
+        updateUnstackedAssetInTimeline(timelineManager, action.assets);
+        break;
+      }
+      case AssetAction.REMOVE_ASSET_FROM_STACK: {
+        timelineManager.addAssets([toTimelineAsset(action.asset)]);
+        if (action.stack) {
+          //Have to unstack then restack assets in timeline in order to update the stack count in the timeline.
+          updateUnstackedAssetInTimeline(
+            timelineManager,
+            action.stack.assets.map((asset) => toTimelineAsset(asset)),
+          );
+          updateStackedAssetInTimeline(timelineManager, {
+            stack: action.stack,
+            toDeleteIds: action.stack.assets
+              .filter((asset) => asset.id !== action.stack?.primaryAssetId)
+              .map((asset) => asset.id),
+          });
+        }
+        break;
+      }
+      case AssetAction.SET_STACK_PRIMARY_ASSET: {
+        //Have to unstack then restack assets in timeline in order for the currently removed new primary asset to be made visible.
+        updateUnstackedAssetInTimeline(
+          timelineManager,
+          action.stack.assets.map((asset) => toTimelineAsset(asset)),
+        );
+        updateStackedAssetInTimeline(timelineManager, {
+          stack: action.stack,
+          toDeleteIds: action.stack.assets
+            .filter((asset) => asset.id !== action.stack.primaryAssetId)
+            .map((asset) => asset.id),
+        });
+        break;
+      }
+    }
+  };
+</script>
+
+{#await import('../asset-viewer/asset-viewer.svelte') then { default: AssetViewer }}
+  <AssetViewer
+    {withStacked}
+    asset={$viewingAsset}
+    preloadAssets={$preloadAssets}
+    {isShared}
+    {album}
+    {person}
+    preAction={handlePreAction}
+    onAction={handleAction}
+    onPrevious={handlePrevious}
+    onNext={handleNext}
+    onRandom={handleRandom}
+    onClose={handleClose}
+  />
+{/await}

web/src/lib/components/timeline/actions/TimelineKeyboardActions.svelte

@@ -0,0 +1,221 @@
+<script lang="ts">
+  import { goto } from '$app/navigation';
+  import { shortcuts, type ShortcutOptions } from '$lib/actions/shortcut';
+  import DeleteAssetDialog from '$lib/components/photos-page/delete-asset-dialog.svelte';
+  import ChangeDate, {
+    type AbsoluteResult,
+    type RelativeResult,
+  } from '$lib/components/shared-components/change-date.svelte';
+  import {
+    setFocusToAsset as setFocusAssetInit,
+    setFocusTo as setFocusToInit,
+  } from '$lib/components/timeline/actions/focus-actions';
+  import { AppRoute } from '$lib/constants';
+  import { TimelineManager } from '$lib/managers/timeline-manager/timeline-manager.svelte';
+  import type { TimelineAsset } from '$lib/managers/timeline-manager/types';
+  import ShortcutsModal from '$lib/modals/ShortcutsModal.svelte';
+  import type { AssetInteraction } from '$lib/stores/asset-interaction.svelte';
+  import { assetViewingStore } from '$lib/stores/asset-viewing.store';
+  import { showDeleteModal } from '$lib/stores/preferences.store';
+  import { searchStore } from '$lib/stores/search.svelte';
+  import { featureFlags } from '$lib/stores/server-config.store';
+  import { handlePromiseError } from '$lib/utils';
+  import { deleteAssets, updateStackedAssetInTimeline } from '$lib/utils/actions';
+  import { archiveAssets, cancelMultiselect, selectAllAssets, stackAssets } from '$lib/utils/asset-utils';
+  import { AssetVisibility } from '@immich/sdk';
+  import { modalManager } from '@immich/ui';
+  import { DateTime } from 'luxon';
+  let { isViewing: showAssetViewer } = assetViewingStore;
+
+  interface Props {
+    timelineManager: TimelineManager;
+    assetInteraction: AssetInteraction;
+    isShowDeleteConfirmation: boolean;
+    onEscape?: () => void;
+    scrollToAsset: (asset: TimelineAsset) => boolean;
+  }
+
+  let {
+    timelineManager = $bindable(),
+    assetInteraction,
+    isShowDeleteConfirmation = $bindable(false),
+    onEscape,
+    scrollToAsset,
+  }: Props = $props();
+
+  let isShowSelectDate = $state(false);
+
+  const trashOrDelete = async (force: boolean = false) => {
+    isShowDeleteConfirmation = false;
+    await deleteAssets(
+      !(isTrashEnabled && !force),
+      (assetIds) => timelineManager.removeAssets(assetIds),
+      assetInteraction.selectedAssets,
+      !isTrashEnabled || force ? undefined : (assets) => timelineManager.addAssets(assets),
+    );
+    assetInteraction.clearMultiselect();
+  };
+
+  const onDelete = () => {
+    const hasTrashedAsset = assetInteraction.selectedAssets.some((asset) => asset.isTrashed);
+
+    if ($showDeleteModal && (!isTrashEnabled || hasTrashedAsset)) {
+      isShowDeleteConfirmation = true;
+      return;
+    }
+    handlePromiseError(trashOrDelete(hasTrashedAsset));
+  };
+
+  const onForceDelete = () => {
+    if ($showDeleteModal) {
+      isShowDeleteConfirmation = true;
+      return;
+    }
+    handlePromiseError(trashOrDelete(true));
+  };
+
+  const onStackAssets = async () => {
+    const result = await stackAssets(assetInteraction.selectedAssets);
+
+    updateStackedAssetInTimeline(timelineManager, result);
+
+    onEscape?.();
+  };
+
+  const toggleArchive = async () => {
+    const visibility = assetInteraction.isAllArchived ? AssetVisibility.Timeline : AssetVisibility.Archive;
+    const ids = await archiveAssets(assetInteraction.selectedAssets, visibility);
+    timelineManager.updateAssetOperation(ids, (asset) => {
+      asset.visibility = visibility;
+      return { remove: false };
+    });
+    deselectAllAssets();
+  };
+
+  let shiftKeyIsDown = $state(false);
+
+  const deselectAllAssets = () => {
+    cancelMultiselect(assetInteraction);
+  };
+
+  const onKeyDown = (event: KeyboardEvent) => {
+    if (searchStore.isSearchEnabled) {
+      return;
+    }
+
+    if (event.key === 'Shift') {
+      event.preventDefault();
+      shiftKeyIsDown = true;
+    }
+  };
+
+  const onKeyUp = (event: KeyboardEvent) => {
+    if (searchStore.isSearchEnabled) {
+      return;
+    }
+
+    if (event.key === 'Shift') {
+      event.preventDefault();
+      shiftKeyIsDown = false;
+    }
+  };
+
+  const onSelectStart = (e: Event) => {
+    if (assetInteraction.selectionActive && shiftKeyIsDown) {
+      e.preventDefault();
+    }
+  };
+
+  const isTrashEnabled = $derived($featureFlags.loaded && $featureFlags.trash);
+  const isEmpty = $derived(timelineManager.isInitialized && timelineManager.months.length === 0);
+  const idsSelectedAssets = $derived(assetInteraction.selectedAssets.map(({ id }) => id));
+  let isShortcutModalOpen = false;
+
+  const handleOpenShortcutModal = async () => {
+    if (isShortcutModalOpen) {
+      return;
+    }
+
+    isShortcutModalOpen = true;
+    await modalManager.show(ShortcutsModal, {});
+    isShortcutModalOpen = false;
+  };
+
+  $effect(() => {
+    if (isEmpty) {
+      assetInteraction.clearMultiselect();
+    }
+  });
+
+  const setFocusTo = setFocusToInit.bind(undefined, scrollToAsset, timelineManager);
+  const setFocusAsset = setFocusAssetInit.bind(undefined, scrollToAsset);
+
+  let shortcutList = $derived(
+    (() => {
+      if (searchStore.isSearchEnabled || $showAssetViewer) {
+        return [];
+      }
+
+      const shortcuts: ShortcutOptions[] = [
+        { shortcut: { key: '?', shift: true }, onShortcut: handleOpenShortcutModal },
+        { shortcut: { key: '/' }, onShortcut: () => goto(AppRoute.EXPLORE) },
+        { shortcut: { key: 'A', ctrl: true }, onShortcut: () => selectAllAssets(timelineManager, assetInteraction) },
+        { shortcut: { key: 'ArrowRight' }, onShortcut: () => setFocusTo('earlier', 'asset') },
+        { shortcut: { key: 'ArrowLeft' }, onShortcut: () => setFocusTo('later', 'asset') },
+        { shortcut: { key: 'D' }, onShortcut: () => setFocusTo('earlier', 'day') },
+        { shortcut: { key: 'D', shift: true }, onShortcut: () => setFocusTo('later', 'day') },
+        { shortcut: { key: 'M' }, onShortcut: () => setFocusTo('earlier', 'month') },
+        { shortcut: { key: 'M', shift: true }, onShortcut: () => setFocusTo('later', 'month') },
+        { shortcut: { key: 'Y' }, onShortcut: () => setFocusTo('earlier', 'year') },
+        { shortcut: { key: 'Y', shift: true }, onShortcut: () => setFocusTo('later', 'year') },
+        { shortcut: { key: 'G' }, onShortcut: () => (isShowSelectDate = true) },
+      ];
+      if (onEscape) {
+        shortcuts.push({ shortcut: { key: 'Escape' }, onShortcut: onEscape });
+      }
+
+      if (assetInteraction.selectionActive) {
+        shortcuts.push(
+          { shortcut: { key: 'Delete' }, onShortcut: onDelete },
+          { shortcut: { key: 'Delete', shift: true }, onShortcut: onForceDelete },
+          { shortcut: { key: 'D', ctrl: true }, onShortcut: () => deselectAllAssets() },
+          { shortcut: { key: 's' }, onShortcut: () => onStackAssets() },
+          { shortcut: { key: 'a', shift: true }, onShortcut: toggleArchive },
+        );
+      }
+
+      return shortcuts;
+    })(),
+  );
+</script>
+
+<svelte:document onkeydown={onKeyDown} onkeyup={onKeyUp} onselectstart={onSelectStart} use:shortcuts={shortcutList} />
+
+{#if isShowDeleteConfirmation}
+  <DeleteAssetDialog
+    size={idsSelectedAssets.length}
+    onCancel={() => (isShowDeleteConfirmation = false)}
+    onConfirm={() => handlePromiseError(trashOrDelete(true))}
+  />
+{/if}
+
+{#if isShowSelectDate}
+  <ChangeDate
+    withDuration={false}
+    title="Navigate to Time"
+    initialDate={DateTime.now()}
+    timezoneInput={false}
+    onConfirm={async (dateString: AbsoluteResult | RelativeResult) => {
+      isShowSelectDate = false;
+      if (dateString.mode == 'absolute') {
+        const asset = await timelineManager.getClosestAssetToDate(
+          (DateTime.fromISO(dateString.date) as DateTime<true>).toObject(),
+        );
+        if (asset) {
+          setFocusAsset(asset);
+        }
+      }
+    }}
+    onCancel={() => (isShowSelectDate = false)}
+  />
+{/if}

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

@@ -23,11 +23,11 @@ export type TimelineDateTime = TimelineDate & {
   millisecond: number;
 };
 
-export type ScrubberListener = (
-  scrubberMonth: { year: number; month: number },
-  overallScrollPercent: number,
-  scrubberMonthScrollPercent: number,
-) => void | Promise<void>;
+export type ScrubberListener = (scrubberData: {
+  scrubberMonth: { year: number; month: number };
+  overallScrollPercent: number;
+  scrubberMonthScrollPercent: number;
+}) => void | Promise<void>;
 
 // used for AssetResponseDto.dateTimeOriginal, amongst others
 export const fromISODateTime = (isoDateTime: string, timeZone: string): DateTime<true> =>