Add previous/next album controls to the drawer

css/style.css

@@ -1931,6 +1931,54 @@ body.bes-drawer-expanded #pgBd {
   flex: 0 0 auto;
 }
 
+/* Previous/next album controls */
+.bes-album-toolbar {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 8px;
+  margin-bottom: 12px;
+  padding: 0 16px 0 20px;
+}
+
+.bes-album-toolbar .bes-album-buy {
+  margin-bottom: 0;
+  padding: 0;
+}
+
+.bes-album-nav {
+  display: flex;
+  gap: 4px;
+}
+
+.bes-album-nav button {
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  padding: 4px 8px;
+  font-size: 13px;
+  font-weight: 500;
+  color: var(--bes-text-strong);
+  background: none;
+  border: 1px solid transparent;
+  border-radius: 4px;
+  cursor: pointer;
+}
+
+.bes-album-nav button:hover:not(:disabled) {
+  background: var(--bes-surface-1);
+  color: var(--bes-text-max);
+}
+
+.bes-album-nav button:disabled {
+  opacity: 0.3;
+  cursor: default;
+}
+
+.bes-album-nav.bes-loading {
+  cursor: progress;
+}
+
 /* Play status icons in track list */
 .bes-player-drawer .play_status {
   background: var(--bes-surface-0);

src/components/player/albumNav.ts

@@ -0,0 +1,39 @@
+import { element } from '../dom';
+
+export interface AlbumNavState {
+  hasPrevious: boolean;
+  hasNext: boolean;
+  loading: boolean;
+}
+
+const chevron = (points: string): string =>
+  `<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><polyline points="${points}"></polyline></svg>`;
+
+export function buildAlbumNav(onPrevious: () => void, onNext: () => void): HTMLElement {
+  const previous = element('button', {
+    className: 'bes-album-nav-prev',
+    html: `${chevron('15 18 9 12 15 6')}<span>Previous album</span>`,
+    attributes: { type: 'button', title: 'Previous album' }
+  });
+  const next = element('button', {
+    className: 'bes-album-nav-next',
+    html: `<span>Next album</span>${chevron('9 18 15 12 9 6')}`,
+    attributes: { type: 'button', title: 'Next album' }
+  });
+
+  previous.addEventListener('click', onPrevious);
+  next.addEventListener('click', onNext);
+
+  return element('div', { className: 'bes-album-nav', children: [previous, next] });
+}
+
+export function updateAlbumNav(nav: HTMLElement | null, { hasPrevious, hasNext, loading }: AlbumNavState): void {
+  if (!nav) return;
+
+  const previous = nav.querySelector<HTMLButtonElement>('.bes-album-nav-prev');
+  const next = nav.querySelector<HTMLButtonElement>('.bes-album-nav-next');
+
+  if (previous) previous.disabled = loading || !hasPrevious;
+  if (next) next.disabled = loading || !hasNext;
+  nav.classList.toggle('bes-loading', loading);
+}

src/components/player/index.ts

@@ -1,2 +1,2 @@
 export { createPlayerDrawer } from './drawer';
-export { loadAlbumIntoDrawer, loadNextAlbum, loadPreviousAlbum } from './loader';
+export { loadAlbumIntoDrawer, loadNextAlbum, loadPreviousAlbum, getLoadedAlbumId } from './loader';

src/components/player/loader.ts

@@ -7,17 +7,22 @@ import { buildDrawerPlayer, buildTrackTable, buildAlbumBuyButton } from './build
 import { PlayerCommands, registerPlayerShortcuts } from '../../keyboardShortcuts';
 import { drawOverlay, generateAudioFeatures } from '../../audioFeatures';
 import { volumeIcon, mutedVolumeIcon } from './icons';
-import { replaceChildren } from '../dom';
+import { element, replaceChildren } from '../dom';
 import { inDrawer, allInDrawer, setText, setStyle } from './query';
 import { streamUrlOf, findPlayableTrackAfter, findPlayableTrackBefore } from './trackSelection';
 import { applyTrackState, markRowPlayed } from './trackState';
+import { buildAlbumNav, updateAlbumNav } from './albumNav';
 import {
   selectAlbum,
   hasNextAlbum,
   hasPreviousAlbum,
   nextAlbum,
   previousAlbum,
-  albumArtUrlFor
+  albumArtUrlFor,
+  canLoadMoreAlbums,
+  loadMoreAlbums,
+  revealAlbum,
+  showAlbumControls
 } from '../../discography';
 
 const log = new Logger();
@@ -31,6 +36,9 @@ let drawerPlayerCreated = false;
 let previousVolume = 1.0;
 let configPort: chrome.runtime.Port | null = null;
 let waveformEnabled = true;
+let requestedAlbumId: string | null = null;
+let fetchCaching = false;
+let albumNavLoading = false;
 
 const ALBUM_LOAD_SETTLE_MS = 300;
 
@@ -220,6 +228,8 @@ export async function loadAlbumIntoDrawer(
   port?: chrome.runtime.Port
 ): Promise<void> {
   log.info(`Loading album ${albumId} (${albumType}) into drawer`);
+  requestedAlbumId = albumId;
+  fetchCaching = enableFetchCaching;
 
   try {
     const tralbumDetails = await getTralbumDetails(
@@ -229,6 +239,11 @@ export async function loadAlbumIntoDrawer(
       createFetchFunction(enableFetchCaching)
     );
 
+    if (requestedAlbumId !== albumId) {
+      log.debug(`Album ${albumId} arrived after the drawer moved on`);
+      return;
+    }
+
     currentAlbumData = tralbumDetails;
     selectAlbum(albumId);
 
@@ -243,14 +258,14 @@ export async function loadAlbumIntoDrawer(
     if (drawerPlayerCreated) {
       replaceChildren(
         elements.tracklistContainer,
-        buildAlbumBuyButton(tralbumDetails),
+        albumToolbar(buildAlbumBuyButton(tralbumDetails)),
         buildTrackTable(tralbumDetails)
       );
     } else {
       const parts = buildDrawerPlayer(tralbumDetails);
 
       mountDrawerPlayer(elements, parts);
-      replaceChildren(elements.tracklistContainer, parts.albumBuyButton, parts.tracklistElement);
+      replaceChildren(elements.tracklistContainer, albumToolbar(parts.albumBuyButton), parts.tracklistElement);
       drawerPlayerCreated = true;
 
       startPlayerOnce();
@@ -268,6 +283,52 @@ export async function loadAlbumIntoDrawer(
   }
 }
 
+export function getLoadedAlbumId(): string | null {
+  return requestedAlbumId;
+}
+
+function hasLaterAlbum(): boolean {
+  return hasNextAlbum() || canLoadMoreAlbums();
+}
+
+function albumToolbar(buyButton: HTMLElement | null): HTMLElement | null {
+  if (!showAlbumControls()) return buyButton;
+
+  const nav = buildAlbumNav(
+    () => void skipAlbum(loadPreviousAlbum),
+    () => void skipAlbum(loadNextAlbum)
+  );
+  updateAlbumNav(nav, { hasPrevious: hasPreviousAlbum(), hasNext: hasLaterAlbum(), loading: albumNavLoading });
+
+  return element('div', { className: 'bes-album-toolbar', children: [nav, buyButton] });
+}
+
+function refreshAlbumNav(): void {
+  updateAlbumNav(inDrawer('.bes-album-nav'), {
+    hasPrevious: hasPreviousAlbum(),
+    hasNext: hasLaterAlbum(),
+    loading: albumNavLoading
+  });
+}
+
+async function skipAlbum(load: () => Promise<boolean>): Promise<void> {
+  if (albumNavLoading) return;
+
+  const keepPlaying = Boolean(audioElement && !audioElement.paused);
+  albumNavLoading = true;
+  refreshAlbumNav();
+
+  try {
+    if ((await load()) && keepPlaying) resumePlayback();
+  } catch (error) {
+    log.error(`Failed to skip album: ${error}`);
+  } finally {
+    albumNavLoading = false;
+    refreshAlbumNav();
+    if (currentAlbumData?.tracks) updatePrevNextButtons(currentTrackIndex, currentAlbumData.tracks.length);
+  }
+}
+
 function currentTrack(): TralbumTrack | undefined {
   return currentAlbumData?.tracks?.[currentTrackIndex];
 }
@@ -334,7 +395,7 @@ function updatePrevNextButtons(index: number, totalTracks: number): void {
   const nextButton = inDrawer('.bes-transport-next');
 
   const hasEarlierTrackOrAlbum = index > 0 || hasPreviousAlbum();
-  const hasLaterTrackOrAlbum = index < totalTracks - 1 || hasNextAlbum();
+  const hasLaterTrackOrAlbum = index < totalTracks - 1 || hasLaterAlbum();
 
   prevButton?.classList.toggle('bes-hidden', !hasEarlierTrackOrAlbum);
   nextButton?.classList.toggle('bes-hidden', !hasLaterTrackOrAlbum);
@@ -366,7 +427,7 @@ interface TrackStep {
 const forward: TrackStep = {
   name: 'next',
   nextWithinAlbum: findPlayableTrackAfter,
-  hasAdjacentAlbum: hasNextAlbum,
+  hasAdjacentAlbum: hasLaterAlbum,
   loadAdjacentAlbum: loadNextAlbum,
   entryTrack: tracks => findPlayableTrackAfter(tracks, -1)
 };
@@ -395,7 +456,7 @@ async function step(direction: TrackStep, keepPlaying: boolean): Promise<void> {
   }
 
   log.info(`No playable track ${direction.name}: loading ${direction.name} album in discography`);
-  await direction.loadAdjacentAlbum();
+  if (!(await direction.loadAdjacentAlbum())) return;
 
   setTimeout(() => {
     const entry = direction.entryTrack(currentAlbumData?.tracks);
@@ -600,25 +661,32 @@ function adjustVolumeBy(delta: number): void {
   updateMuteButton(audioElement.volume === 0);
 }
 
-export async function loadNextAlbum(enableFetchCaching: boolean = false): Promise<boolean> {
+export async function loadNextAlbum(enableFetchCaching: boolean = fetchCaching): Promise<boolean> {
+  if (!hasNextAlbum() && canLoadMoreAlbums()) {
+    log.info('Reached the end of the loaded albums, loading more');
+    await loadMoreAlbums();
+  }
+
   const item = nextAlbum();
   if (!item) {
     log.info('No next album available');
     return false;
   }
 
   await loadAlbumIntoDrawer(item.id, item.type, enableFetchCaching);
+  revealAlbum(item);
   return true;
 }
 
-export async function loadPreviousAlbum(enableFetchCaching: boolean = false): Promise<boolean> {
+export async function loadPreviousAlbum(enableFetchCaching: boolean = fetchCaching): Promise<boolean> {
   const item = previousAlbum();
   if (!item) {
     log.info('No previous album available');
     return false;
   }
 
   await loadAlbumIntoDrawer(item.id, item.type, enableFetchCaching);
+  revealAlbum(item);
   return true;
 }
 

src/discography.ts

@@ -8,8 +8,25 @@ export interface DiscographyItem {
   element: Element;
 }
 
+export interface AlbumSource {
+  extract: () => DiscographyItem[];
+  // Pulls more items into the page (e.g. the next page of a feed); resolves true if any arrived.
+  loadMore?: () => Promise<boolean>;
+  reveal?: (item: DiscographyItem) => void;
+  showAlbumControls?: boolean;
+}
+
 let order: DiscographyItem[] = [];
 let selectedIndex = -1;
+const discographySource: AlbumSource = {
+  extract: extractDiscographyOrder,
+  reveal: item => item.element.scrollIntoView?.({ behavior: 'smooth', block: 'center' }),
+  showAlbumControls: true
+};
+
+let source: AlbumSource = discographySource;
+let pendingLoadMore: Promise<boolean> | null = null;
+let sourceExhausted = false;
 
 export function extractDiscographyOrder(): DiscographyItem[] {
   const items: DiscographyItem[] = [];
@@ -33,8 +50,55 @@ export function extractDiscographyOrder(): DiscographyItem[] {
   return items;
 }
 
+export function setAlbumSource(next: AlbumSource): void {
+  source = next;
+  sourceExhausted = false;
+  updateDiscographyOrder();
+}
+
 export function updateDiscographyOrder(): void {
-  order = extractDiscographyOrder();
+  const selectedId = order[selectedIndex]?.id;
+  const previousLength = order.length;
+
+  order = source.extract();
+  if (selectedId) selectedIndex = findAlbumIndexById(selectedId);
+  if (order.length > previousLength) sourceExhausted = false;
+}
+
+export function canLoadMoreAlbums(): boolean {
+  return selectedIndex !== -1 && Boolean(source.loadMore) && !sourceExhausted;
+}
+
+export function loadMoreAlbums(): Promise<boolean> {
+  if (!source.loadMore || sourceExhausted) return Promise.resolve(false);
+
+  pendingLoadMore ??= source
+    .loadMore()
+    .catch(error => {
+      log.warn(`Failed to load more albums: ${error}`);
+      return false;
+    })
+    .then(loaded => {
+      const previousLength = order.length;
+      updateDiscographyOrder();
+
+      const grew = order.length > previousLength;
+      if (!loaded && !grew) sourceExhausted = true;
+      return loaded || grew;
+    })
+    .finally(() => {
+      pendingLoadMore = null;
+    });
+
+  return pendingLoadMore;
+}
+
+export function showAlbumControls(): boolean {
+  return Boolean(source.showAlbumControls) && selectedIndex !== -1 && order.length > 1;
+}
+
+export function revealAlbum(item: DiscographyItem): void {
+  source.reveal?.(item);
 }
 
 export function findAlbumIndexById(albumId: string): number {

src/label_view.ts

@@ -1,5 +1,5 @@
 import Logger from './logger';
-import { createPlayerDrawer, loadAlbumIntoDrawer } from './components/player';
+import { createPlayerDrawer, loadAlbumIntoDrawer, getLoadedAlbumId } from './components/player';
 import { updateDiscographyOrder } from './discography';
 import { setFindMusicLinks, FindMusicLink } from './components/player/findMusicLinks';
 import { extractBandId } from './utilities';
@@ -72,7 +72,7 @@ export function fillFrame(
   const player = drawer();
   const { isOpen, isMinimized } = player.getState();
 
-  if (isOpen && previewState.previewId === target.id) {
+  if (isOpen && getLoadedAlbumId() === target.id) {
     if (isMinimized) player.maximizeDrawer();
     else player.minimizeDrawer();
     return;
@@ -102,7 +102,11 @@ export function attachPreviewListeners(
   previewState: { previewOpen: boolean; previewId?: string },
   enableFetchCaching: boolean = false
 ): void {
-  root.querySelectorAll('.open-iframe').forEach(button => {
+  root.querySelectorAll<HTMLElement>('.open-iframe').forEach(button => {
+    // Feed previews are bound by the feed and again by the label view's page-wide pass.
+    if (button.dataset.besBound === 'true') return;
+
+    button.dataset.besBound = 'true';
     button.addEventListener('click', event => {
       fillFrame(event, previewState, enableFetchCaching, port);
     });