Targeted optimizations for the DMABuf-disabled rendering path where
every frame is software-composited:
- Replace infinite CSS scroll-text animation with transition-based
cycle that only repaints during active scroll, not during pauses
- Remove CSS mask-image on scrolling text (mask + animation was the
single most expensive continuous repaint)
- Replace wa-icon in track rows with inline SVG — eliminates 30-50
shadow DOM trees (each with SVG fetch/parse) during scroll
- Remove hover transitions on album cards, artist cards, genre cards,
fav icons, queue remove buttons — each transition was causing
per-frame software repaints
- Use visibility:hidden instead of opacity:0 for queue remove button
(binary switch vs per-frame alpha blend)
- Add decoding=async to now-playing cover art images (prevents
main-thread blocking during image decode on track change)
- Add contain:strict to fixed-height track rows (33px) and queue
items (49px) — browser skips size contribution calculations
Root causes addressed:
- track-list had no _itemSize hint for flow layout — virtualizer
defaulted to 100px, measured actual ~33px rows, then called
_correctScrollError/scrollTo on every scroll causing visible jumps
- will-change:transform on virtualizer elements caused nested GPU
layers (virtualizer positions children with transforms internally)
adding compositor overhead instead of helping
- content-visibility:auto on album cards conflicted with virtualizer's
own DOM recycling, causing redundant layout recalculation
- track-list visibilityChanged handler wrote to store synchronously
on every event (per-item during scroll) without any throttling
- IIFE closure in renderTrackRow created a new function per row per render
Fixes applied:
- Add _itemSize:{height:33} + fixed height:33px on .track-row (matches
queue-panel pattern that already worked smoothly)
- Add overflow-anchor:none on track-list virtualizer
- Remove will-change:transform from all 6 scroll containers
- Remove content-visibility:auto from album cards
- RAF-throttle visibilityChanged scroll position saves
- Replace IIFE with direct cols.map() in template
- Queue store now uses queueMicrotask batching (matching library store pattern)
- Library store adds changeGeneration counter incremented only on actual data changes
- LibraryController checks changeGeneration before requestUpdate, skipping loading-only transitions
- Reduces unnecessary component re-renders during data loading cycles
- Replace inline arrow closures in renderTrackRow with event delegation via data-index
- Replace inline arrow closures in renderTrackItem with event delegation via data-index
- Add delegated click/dblclick/contextmenu/dragstart handlers on virtualizer elements
- Remove button click in queue panel also delegated via closest('.remove-button')
- Zero new function objects created per renderItem call during scroll
- Replace 100ms debounced scroll save in cover grid with requestAnimationFrame throttling
- Position now saves continuously during scrolling (~16ms) instead of only after stop
- Cancel pending RAF in teardown() to prevent leaks
- Add overflow-anchor: none CSS to queue panel lit-virtualizer
- Keep monkey-patch for lit-virtualizer _correctScrollError with expanded comment explaining why CSS alone is insufficient
- contain: layout style on :host of all 6 scroll-heavy components
- contain: paint + will-change: transform on all scroll containers for GPU compositing
- content-visibility: auto + contain-intrinsic-size on .album-card for off-screen skip
- cover-grid, track-list, queue-panel, artists-view, genres-view, playlist-view
Sections start collapsed showing only heading, description, and a
chevron icon. Click to expand and reveal the fields. The open property
allows sections to start expanded if needed.
Progress bar now renders below the library row being scanned, with
a small status label (phase + percent) after the library name. Removed
the separate status-bar progress display.
Add Library now sits in the same row as Scan and Full Rescan, sharing
the same btn-primary style and size. Removed the standalone button
below the library list.
Scan and Full Rescan buttons now sit above the library list for easier
access. Libraries start unchecked — both buttons are disabled until at
least one library is selected.
recording_genres and release_group_recordings reference recordings.id,
so they must be deleted BEFORE the recordings table is cleaned.
Also extends toast duration to 8s for readability.
RemoveLibrary now polls until the cancelled scan goroutine finishes
before proceeding with the removal transaction. Also show removal
errors as toast messages instead of only logging to console, and
explicitly reload library list after successful removal.
- Add checkboxes to library list with select-all header
- Soft Scan operates on selected libraries (queues each individually)
- Full Rescan stays global (nukes all data, rescans all libraries)
- Remove redundant 'Scan All Libraries' button
- Fix FullRescan Go backend to scan all libraries after wipe, not just first
Scan() wrapper was deleted in Phase 11 but config-page.ts and
library-manager.ts still imported it. Use ScanAllLibraries() for
soft scan since multi-library model scans all libraries.
- Remove 'libraries' from View type union in app-sidebar.ts
- Remove Libraries nav item from sidebar navigation list
- Remove case 'libraries' view routing in index.ts
- Remove library-manager component import from index.ts
- Add libraryId, libraryName, queuedCount to ScanProgress interface
- Replace CancelScan import with CancelCurrentScan, CancelAllScans
- Add ScanAllLibraries import and Scan All Libraries button
- Show library name in progress label (Scanning: [Library Name])
- Show queue count below progress bar when libraries queued
- Cancel dialog shows scope choice (Cancel This Library / Cancel All) when queue > 0
- Subscribe to LibraryScanQueued and LibraryScanQueueDrained events
- Track scanQueuedCount state for queue-aware UI behavior
Task 1: Schema, events, and progress types
- Add library_id to CreateAudioFile SQL INSERT and regenerate sqlc code
- Add LibraryScanQueued and LibraryScanQueueDrained event constants
- Regenerate TypeScript events via genevents
- Add LibraryID, LibraryName, QueuedCount to ScanProgress
- Add LibraryID, LibraryName to ScanMetrics
- Add libraryID field to importResult for threading through pipeline
Task 2: Scan queue coordinator and per-library scanning
- Create scan_queue.go with ScanLibrary(id), ScanAllLibraries()
- Add CancelCurrentScan(), CancelAllScans() for queue-aware cancellation
- FIFO scan queue with silent dedup (same library already scanning or queued)
- Refactor Scan() -> scanInternal(libraryID, libraryName, libraryPath)
- Replace GetAllAudioFiles with GetAudioFilesByLibrary for per-library loading
- Thread libraryID through DB writer to set CreateAudioFileParams.LibraryID
- drainQueue auto-starts next queued library or emits LibraryScanQueueDrained
- Pause freezes current scan AND queue
- Add GetScanQueueLength() and QueuedLibraryNames() for UI
- Mark CancelScan() and Scan() as deprecated
- New playlist-details component with header (back button, playlist icon, title, track count)
- Full track list with all interactions: select, play, context menu, drag, phantom handling
- Drop target support for adding tracks from other views
- Search filtering for tracks within the detail view
- Navigation routing in index.ts for playlist-details view
- Added playlist-details to SEARCHABLE_VIEWS in search-store
lit-virtualizer's flow layout has a scroll error correction mechanism that
calls scrollTo() to fix sub-pixel estimation errors. On large lists (20k+),
even with fixed-height items, floating-point differences from
getBoundingClientRect() (e.g. 49.000003px vs 49px) accumulate across items
and trigger corrections that fight the native scrollbar drag gesture,
causing the thumb to desync from the mouse.
Detect scrollbar drag by checking if mousedown occurs in the scrollbar
gutter (clientX > element clientWidth), then monkey-patch the virtualizer's
_correctScrollError method to discard accumulated errors during drag
instead of calling scrollTo(). Items continue to render/recycle normally
since layout updates are not suppressed -- only the scroll position
corrections are skipped.
The previous fix (fixed CSS height on .track-item) was insufficient because
lit-virtualizer's flow layout defaults to estimating items at 100px tall.
With 20k items, the difference between 100px estimate and 49px actual creates
a ~1M px scroll height that collapses as items get measured, triggering
scroll error corrections (programmatic scrollTo calls) that fight the native
scrollbar during drag.
Setting _itemSize to { height: 49 } via the flow() config ensures the initial
scroll size estimate matches reality, eliminating the scroll error corrections
that caused the scrollbar thumb to desync from the mouse when dragging down.
- Add handleSelectAll bound handler calling selection.selectAll() in all three components
- Register/unregister event listeners in connectedCallback/disconnectedCallback
- Add selectAll() method to SelectionController that selects all items via host interface
- Change app.selectAll dispatch from document.execCommand('selectAll') to CustomEvent('shortcut:select-all')
- Pause/Resume buttons replace Soft Scan/Full Rescan during active scan
- Cancel button shows confirmation dialog with Keep/Discard/Continue options
- Register LibraryScanPaused/Resumed/Cancelled event handlers
- Status bar shows 'Scan paused.' with accent color when paused
- Add CancelScan/PauseScan/ResumeScan Wails binding stubs
- Cancel dialog overlay dismissible by clicking outside or Continue Scanning
- Add cancelled field to ScanMetrics TypeScript interface
- Create keyboard-shortcut-service.ts singleton with keydown listener
- Shadow DOM active element resolution for scope detection
- Text input suppression (only Escape passes through)
- Scope resolution: text-input > panel-specific > global
- Action dispatch to player/queue stores and Wails bindings
- Create shortcuts-store.ts with Wails persistence and event sync
- Create shortcuts-controller.ts for Lit component integration
- Export store and controller from store/index.ts
- Replace hardcoded Ctrl+F handler in index.ts with service
- Initialize service via import in frontend/index.ts
- Add LibraryScanCancelled, LibraryScanPaused, LibraryScanResumed events
- Regenerate frontend/src/events.ts via go generate
- Add Cancelled bool field to ScanMetrics struct
Move search indicator from absolute-positioned overlay into sort toolbar
(or dedicated search-bar-row for artists/genres views). Shows indicator
on empty-state screens. Fix cover art not displaying for expanded album
tracks by checking expandedAlbumId before the albumName guard. Add
ScanWarning model bindings.
- Add FavoritesController and classMap imports
- Add .fav-icon CSS with compact sizing (18px/11px) for dropdown context
- Insert heart/star icon between track number and title
- Click toggles favorite with stopPropagation to avoid track selection
Add live progress reporting during library scans:
- Pre-walk count: fast WalkDir to count audio files upfront for
percentage calculation (~1-2s overhead)
- Progress ticker: emits ScanProgress events every 300ms with
phase, file counts (added/skipped/updated), and total
- Phase labels: counting → scanning → thumbnails → orphans
- Frontend: progress bar with percentage, file counts breakdown,
and phase indicator in both config-page and library-manager
Replaces the static 'Scanning...' text with a live progress bar
showing e.g. '62% — Scanning... 1,247 / 2,013 files (891 new,
356 skipped)'
- Add height: 49px and overflow: hidden to .track-item CSS
- Add overflow: hidden to .track-details CSS
- Fixed height ensures lit-virtualizer _scrollSize is stable from first render
- Prevents scrollbar lag on large queues (20k+ tracks) caused by dynamic item size averaging
repeat() as child content of lit-virtualizer bypasses virtualization,
rendering ALL items instead of only visible ones. This caused 2+ minute
loading times and UI freezing with large libraries.
The correct approach: use lit-virtualizer's native .renderItem and
.keyFunction properties which integrate with its scroll-based viewport
management.
- cover-grid dynamic text tiers use --yj-text-xs/sm/md/lg tokens
- track-list sort toolbar, row text, and fav icon use design tokens
- queue-panel header and track text use type scale tokens
- track-details, track-info, artist-details, genre-details use tokens
- designTokens imported and prepended to static styles in all 8 files
- Sidebar: convert all em-based padding/gap to px values, icon sizes to --yj-icon-md
- Now-playing: cover placeholder icon to --yj-icon-lg, text sizes to type tokens
- Search-bar: search icon to --yj-icon-sm, input font to --yj-text-md
- Audio-player: convert em-based gap/padding/margin to px values
- Seek-bar: tooltip font to --yj-text-lg, margin from em to px
- Volume-control: padding/margin from em to px, thumb sizes from em to px
- All components import designTokens and include in static styles
- Hoist searchCtrl.term lookup outside per-column loop in renderTrackRow
- Search highlighting already short-circuits when search term is empty
- Import classMap in queue-panel.ts
- Replace array filter/join class construction with classMap in renderTrackItem
- Eliminates per-row array allocation in queue panel render hot path
- Import classMap from lit/directives/class-map.js
- Replace array filter/join class construction with classMap for track-row
- Convert fav-icon conditional class to classMap
- Convert cell alignment classes to classMap
- Eliminates per-row array allocation and string join in render hot path
- cover-grid: all 3 virtualizers (single, before-split, after-split) use repeat() with album.ID key
- artists-view uses repeat() with artist.ID key
- genres-view uses repeat() with genre.name key
- Removed gridKeyFunction (now inlined in repeat calls)
- Removed .renderItem and .keyFunction properties from all virtualizers
- New tokens.css.ts exports designTokens with --yj-icon-sm/md/lg and --yj-text-xs/sm/md/lg/xl
- Values derived from existing pixel sizes scattered across codebase
- :host scoped for component-level adoption via static styles array
- Library store notify() coalesces multiple calls per microtask tick into one subscriber notification
- Search input debounces store propagation by 150ms while keeping instant visual feedback
- Empty search input clears immediately for responsive UX
- Remove eagerFetch() call from LibraryStore constructor
- Add deferEagerFetch() that waits for DOMContentLoaded event
- App shell renders before backend data roundtrips begin
- All 4 data types (tracks, albums, artists, genres) still loaded eagerly
- invalidate() still calls eagerFetch() directly for post-scan refresh