// stores/auth.ts
export const useAuthStore = defineStore('auth', () => {
  const accessToken = ref<string | null>(null);
  const refreshToken = ref<string | null>(localStorage.getItem('refresh_token'));
  const user = ref<User | null>(null);
  const deviceId = getOrCreateDeviceId();

  const isAuthenticated = computed(() => !!accessToken.value);

  async function login(email: string, password: string) {
    const response = await authApi.login({ email, password, deviceId });
    accessToken.value = response.accessToken;
    refreshToken.value = response.refreshToken;
    user.value = response.user;
    localStorage.setItem('refresh_token', response.refreshToken);
  }

  async function refreshTokens() { /* ... */ }
  async function logout() { /* ... */ }

  return { accessToken, user, isAuthenticated, deviceId, login, refreshTokens, logout };
});

// composables/useTracks.ts
export function useTracks(filters: Ref<TrackFilters>) {
  return useInfiniteQuery({
    queryKey: ['tracks', filters],
    queryFn: ({ pageParam }) => tracksApi.listTracks({
      ...filters.value,
      cursor: pageParam,
    }),
    getNextPageParam: (lastPage) => lastPage.nextCursor,
    staleTime: 5 * 60 * 1000,
  });
}

// stores/player.ts
export const usePlayerStore = defineStore('player', () => {
  const audio = ref<HTMLAudioElement | null>(null);
  const currentTrack = ref<Track | null>(null);
  const isPlaying = ref(false);
  const currentTime = ref(0);
  const duration = ref(0);
  const volume = ref(1);
  const queue = ref<Track[]>([]);

  async function play(track: Track) {
    if (currentTrack.value?.id !== track.id) {
      currentTrack.value = track;
      const { streamUrl } = await streamApi.getStreamUrl(track.id);
      if (!audio.value) {
        audio.value = new Audio();
        setupAudioListeners();
      }
      audio.value.src = streamUrl;
    }
    await audio.value?.play();
    isPlaying.value = true;
    await reportTelemetry('play_start');
  }

  // ... pause, seek, playNext, playPrevious, etc.
});

// packages/core/src/telemetry/playback.ts
export async function reportPlaybackEvent(event: PlaybackEvent): Promise<void> {
  const hashedDeviceId = hashDeviceId(getOrCreateDeviceId());

  await telemetryApi.ingestPlayback({
    eventType: event.type,
    trackId: event.trackId,
    clientTimestamp: new Date().toISOString(),
    positionSeconds: event.position,
    sessionId: event.sessionId,
    deviceId: hashedDeviceId,
    clientVersion: import.meta.env.VITE_APP_VERSION,
  });
}

// src/router/index.ts
const routes = [
  {
    path: '/auth',
    component: () => import('@/layouts/AuthLayout.vue'),
    children: [
      { path: 'login', name: 'login', component: () => import('@/features/auth/LoginPage.vue') },
      { path: 'register', name: 'register', component: () => import('@/features/auth/RegisterPage.vue') },
    ],
  },
  {
    path: '/',
    component: () => import('@/layouts/MainLayout.vue'),
    meta: { requiresAuth: true },
    children: [
      { path: '', name: 'library', component: () => import('@/features/library/LibraryPage.vue') },
      { path: 'track/:id', name: 'track', component: () => import('@/features/library/TrackDetailPage.vue') },
      { path: 'playlists', name: 'playlists', component: () => import('@/features/playlists/PlaylistsPage.vue') },
      { path: 'playlist/:id', name: 'playlist', component: () => import('@/features/playlists/PlaylistDetailPage.vue') },
      { path: 'upload', name: 'upload', component: () => import('@/features/upload/UploadPage.vue') },
    ],
  },
];

<template>
  <div class="flex h-screen flex-col">
    <AppHeader />
    <div class="flex flex-1 overflow-hidden">
      <Sidebar />
      <main class="flex-1 overflow-y-auto p-6">
        <RouterView />
      </main>
    </div>
    <PlayerBar />
  </div>
</template>

// features/library/__tests__/TrackCard.test.ts
describe('TrackCard', () => {
  it('renders track information', () => {
    render(TrackCard, {
      props: { track: mockTrack },
      global: { plugins: [createTestingPinia()] },
    });
    expect(screen.getByText('Test Track')).toBeInTheDocument();
  });
});

// e2e/auth.spec.ts
test('user can log in and see library', async ({ page }) => {
  await page.goto('/auth/login');
  await page.fill('[data-testid="email"]', '[email protected]');
  await page.fill('[data-testid="password"]', 'password123');
  await page.click('[data-testid="login-button"]');
  await expect(page).toHaveURL('/');
});