Connect Apple Music and Spotify-via-Last.fm on iPhone

- Local Expo module (Swift): MusicKit authorization, Music User Token via MusicUserTokenProvider, and live Music app now-playing while the app is open (MediaPlayer notifications), reported through the device endpoint - One-tap Apple Music onboarding on iOS; Apple Music row in Settings - Sign in with Last.fm, plus a guided Spotify-via-Last.fm flow when direct Spotify sign-in is capped - Device registration moved to shared code used by Android and iOS Not yet compiled for iOS (no Xcode here); needs an EAS build. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01MzFywujuH9TiuXbr9vjoX8
2026-10-04 07:12:19 -04:00
parent ca97f1c3ac
commit 1d4aeee0dd
16 changed files with 522 additions and 78 deletions
@@ -0,0 +1,80 @@
+import { useEffect } from 'react';
+import { AppState } from 'react-native';
+import AppleMusic, { type MusicAppPlayback } from '@/modules/apple-music';
+import { api } from './api';
+import { reportPlayback } from './device';
+
+/** True on iOS builds that include the native module (not Android, web, or Expo Go). */
+export const appleMusicAvailable = AppleMusic !== null;
+
+export class AppleMusicPermissionError extends Error {}
+
+/**
+ * The whole Apple Music setup: one system prompt. Asks for access, exchanges
+ * our developer token for the user's Music User Token, and hands it to the
+ * server, which then follows recently played in the background.
+ */
+export async function connectAppleMusic() {
+  if (!AppleMusic) throw new Error('Apple Music is only available in the iPhone app');
+  let status = AppleMusic.authorizationStatus();
+  if (status === 'notDetermined') status = await AppleMusic.requestAuthorization();
+  if (status !== 'authorized') {
+    throw new AppleMusicPermissionError(
+      status === 'restricted'
+        ? 'Apple Music access is restricted on this iPhone (Screen Time or a device profile).'
+        : 'Turn on Media & Apple Music for musicshare in the Settings app, then try again.',
+    );
+  }
+  const { token } = await api.appleMusicDeveloperToken();
+  const musicUserToken = await AppleMusic.getUserToken(token);
+  return api.connectAppleMusic(musicUserToken);
+}
+
+const HEARTBEAT_MS = 4 * 60_000; // the server expires silent phones after 9 minutes
+let lastSent: { key: string; at: number } | null = null;
+
+function report(playback: MusicAppPlayback) {
+  const key = 'title' in playback ? `${playback.state}|${playback.title}|${playback.artist}` : 'stopped';
+  const now = Date.now();
+  if (lastSent?.key === key && (playback.state !== 'playing' || now - lastSent.at < HEARTBEAT_MS)) return;
+  if (!lastSent && key === 'stopped') return; // nothing was shared yet; no need to say "stopped"
+  lastSent = { key, at: now };
+  reportPlayback(
+    'title' in playback && playback.state !== 'stopped'
+      ? {
+          app: 'com.apple.Music',
+          appName: 'Apple Music',
+          state: playback.state,
+          track: {
+            title: playback.title,
+            artist: playback.artist,
+            album: playback.album || null,
+            durationMs: playback.durationMs > 0 ? Math.round(playback.durationMs) : null,
+          },
+        }
+      : { app: 'com.apple.Music', appName: 'Apple Music', state: 'stopped' },
+  ).catch(() => {
+    lastSent = null; // retry on the next change
+  });
+}
+
+/**
+ * While the app is open, mirror the Music app exactly. iOS doesn't let us watch
+ * it in the background; then the server's recently-played polling takes over.
+ */
+export function useAppleMusicLive(enabled: boolean) {
+  useEffect(() => {
+    if (!enabled || !AppleMusic || AppleMusic.authorizationStatus() !== 'authorized') return;
+    const music = AppleMusic;
+    const check = () => music.getNowPlaying().then(report).catch(() => {});
+    check();
+    const changes = music.addListener('onNowPlayingChange', report);
+    const foreground = AppState.addEventListener('change', (s) => s === 'active' && check());
+    const heartbeat = setInterval(check, HEARTBEAT_MS);
+    return () => {
+      changes.remove();
+      foreground.remove();
+      clearInterval(heartbeat);
+    };
+  }, [enabled]);
+}