fix: iTunes functions fall back to direct Apple API when backend not configured

_iGet now tries backend proxy first (if backendUrl set), falls back to direct
Apple API URL so iTunes search/lookup/charts work regardless of backend config.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/api.js

@@ -39,49 +39,71 @@ export async function ndAuth() {
   return S._ndToken;
 }
 
-// ─── ITUNES (proxied through backend to avoid Apple's browser origin block) ───
-function _iBase() { return S.cfg.backendUrl || ''; }
+// ─── ITUNES ───
+// Try backend proxy first (avoids Apple's 403 browser-origin block).
+// Fall back to direct Apple API if no backend is configured or proxy fails.
+const ITUNES = 'https://itunes.apple.com';
+const APPLE_RSS = 'https://rss.applemarketingtools.com';
 
-async function _iGet(path) {
+async function _fetch(url) {
   try {
-    const r = await fetch(_iBase() + path);
-    if (!r.ok) return {};
-    return await r.json();
+    const r = await fetch(url);
+    const text = await r.text();
+    if (!text) return {};
+    return JSON.parse(text);
   } catch { return {}; }
 }
 
+async function _iGet(proxyPath, directUrl) {
+  const base = S.cfg.backendUrl;
+  if (base) {
+    const d = await _fetch(base + proxyPath);
+    if (d && Object.keys(d).length) return d;
+  }
+  return directUrl ? _fetch(directUrl) : {};
+}
+
 export async function itunesSearch(query, entity='musicTrack', limit=25) {
-  const d = await _iGet(`/api/itunes/search?term=${encodeURIComponent(query)}&entity=${entity}&limit=${limit}`);
+  const qs = `term=${encodeURIComponent(query)}&media=music&entity=${entity}&limit=${limit}&country=us&explicit=Yes`;
+  const d = await _iGet(`/api/itunes/search?term=${encodeURIComponent(query)}&entity=${entity}&limit=${limit}`,
+                         `${ITUNES}/search?${qs}`);
   return d.results || [];
 }
 
 export async function itunesLookupAlbum(collectionId) {
-  const d = await _iGet(`/api/itunes/lookup?id=${collectionId}&entity=song`);
+  const d = await _iGet(`/api/itunes/lookup?id=${collectionId}&entity=song`,
+                         `${ITUNES}/lookup?id=${collectionId}&entity=song&explicit=Yes`);
   return (d.results || []).filter(x => x.wrapperType === 'track');
 }
 
 export async function itunesLookupArtistSongs(artistId, limit=15) {
-  const d = await _iGet(`/api/itunes/lookup?id=${artistId}&entity=song&limit=${limit}`);
+  const d = await _iGet(`/api/itunes/lookup?id=${artistId}&entity=song&limit=${limit}`,
+                         `${ITUNES}/lookup?id=${artistId}&entity=song&limit=${limit}&country=us&explicit=Yes`);
   return (d.results || []).filter(x => x.wrapperType === 'track');
 }
 
 export async function itunesLookupArtistAlbums(artistId, limit=200) {
-  const d = await _iGet(`/api/itunes/lookup?id=${artistId}&entity=album&limit=${limit}`);
+  const d = await _iGet(`/api/itunes/lookup?id=${artistId}&entity=album&limit=${limit}`,
+                         `${ITUNES}/lookup?id=${artistId}&entity=album&limit=${limit}&country=us`);
   return (d.results || []).filter(x => x.wrapperType === 'collection' && x.collectionType === 'Album');
 }
 
 export async function itunesTopCharts() {
   for (const country of ['de', 'us']) {
-    const d = await _iGet(`/api/itunes/charts?type=albums&country=${country}`);
-    if (d.results?.length) return d.results;
+    const d = await _iGet(`/api/itunes/charts?type=albums&country=${country}`,
+                           `${APPLE_RSS}/api/v2/${country}/music/most-played/50/albums.json`);
+    const results = d.results || d.feed?.results;
+    if (results?.length) return results;
   }
   return [];
 }
 
 export async function itunesTopSongs() {
   for (const country of ['de', 'us']) {
-    const d = await _iGet(`/api/itunes/charts?type=songs&country=${country}`);
-    if (d.results?.length) return d.results;
+    const d = await _iGet(`/api/itunes/charts?type=songs&country=${country}`,
+                           `${APPLE_RSS}/api/v2/${country}/music/most-played/50/songs.json`);
+    const results = d.results || d.feed?.results;
+    if (results?.length) return results;
   }
   return [];
 }