// Talks ONLY to our own backend now - never directly to Emby. The backend
// holds the real Emby session (server/src/embyAuth.js); this module just
// wraps fetch calls to our own /api/* routes. See docs/architecture.md for
// why this changed from the first version (CORS, plus not wanting the
// browser to hold an Emby token at all).

async function apiFetch(path, options = {}) {
  const res = await fetch(path, {
    credentials: 'same-origin',
    ...options,
    headers: { 'Content-Type': 'application/json', ...(options.headers || {}) }
  });
  if (!res.ok) {
    const body = await res.json().catch(() => ({}));
    throw new Error(body.error || `Request failed: ${res.status}`);
  }
  return res.json();
}

export const auth = {
  userName: null,
  get isLoggedIn() { return !!this.userName; }
};

/** Call once on app start to find out if our session cookie is still valid. */
export async function restoreSession() {
  try {
    const data = await apiFetch('/api/auth/me');
    auth.userName = data.userName;
    return true;
  } catch (err) {
    auth.userName = null;
    return false;
  }
}

export async function login(username, password) {
  const data = await apiFetch('/api/auth/login', {
    method: 'POST',
    body: JSON.stringify({ username, password })
  });
  auth.userName = data.userName;
  return data;
}

export async function logout() {
  await apiFetch('/api/auth/logout', { method: 'POST' }).catch(() => {});
  auth.userName = null;
}

export async function searchItems(query) {
  if (!query || query.trim().length < 2) return [];
  const data = await apiFetch(`/api/catalog/search?q=${encodeURIComponent(query)}`);
  return data.items || [];
}

export async function getItem(itemId) {
  return apiFetch(`/api/catalog/item/${itemId}`);
}

export async function getLibraries() {
  const data = await apiFetch('/api/catalog/libraries');
  return data.libraries || [];
}

export async function getLibraryItems(libraryId) {
  const data = await apiFetch(`/api/catalog/libraries/${libraryId}/items`);
  return data.items || [];
}

export async function getRecentItems(libraryId) {
  const data = await apiFetch(`/api/catalog/libraries/${libraryId}/recent`);
  return data.items || [];
}

export async function getSeriesSeasons(seriesId) {
  const data = await apiFetch(`/api/catalog/series/${seriesId}/seasons`);
  return data.seasons || [];
}

export async function getSeriesEpisodes(seriesId, seasonId) {
  const data = await apiFetch(`/api/catalog/series/${seriesId}/episodes?seasonId=${encodeURIComponent(seasonId)}`);
  return data.episodes || [];
}

export async function getArtists(libraryId) {
  const data = await apiFetch(`/api/catalog/libraries/${libraryId}/artists`);
  return data.artists || [];
}

export async function getArtistAlbums(artistId) {
  const data = await apiFetch(`/api/catalog/artists/${artistId}/albums`);
  return data.albums || [];
}

export async function getAlbumTracks(albumId) {
  const data = await apiFetch(`/api/catalog/albums/${albumId}/tracks`);
  return data.tracks || [];
}

export async function getPlaybackOptions(itemId) {
  return apiFetch(`/api/catalog/item/${itemId}/playback-options`);
}

/** `options` may carry AudioStreamIndex/SubtitleStreamIndex/MaxStreamingBitrate/mediaType. */
export function streamUrl(itemId, options = {}) {
  const qs = new URLSearchParams(
    Object.fromEntries(Object.entries(options).filter(([, v]) => v !== '' && v != null))
  ).toString();
  return `/api/catalog/stream/${itemId}/master.m3u8${qs ? '?' + qs : ''}`;
}

/** Same stream, tagged for a music track - see server/src/index.js's
 *  /master.m3u8 route for why mediaType is the one thing that matters here
 *  (its hand-built-fallback path is genuinely different for audio). */
export function audioStreamUrl(itemId) {
  return streamUrl(itemId, { mediaType: 'audio' });
}