feat: implement podcast discovery and management controllers and services

backend/src/controllers/podcastController.ts

@@ -291,7 +291,8 @@ export const subscribeFromDiscovery = async (req: Request, res: Response) => {
 export const getTrendingPodcasts = async (req: Request, res: Response) => {
   try {
     const limit = Number(req.query.limit) || 20;
-    const trending = await podcastIndexService.getTrendingPodcasts(limit);
+    const genre = req.query.genre as string;
+    const trending = await podcastIndexService.getTrendingPodcasts(limit, genre);
     res.json({ source: 'itunes', podcasts: trending, count: trending.length });
   } catch (error: any) {
     console.error('Trending podcasts error:', error.message);

backend/src/services/podcastIndexService.ts

@@ -77,9 +77,11 @@ export const podcastIndexService = {
       .filter((r): r is SearchResult => r !== null);
   },
 
-  getTrendingPodcasts: async (limit: number = 20): Promise<SearchResult[]> => {
-    // iTunes official top podcasts RSS (France)
+  getTrendingPodcasts: async (limit: number = 20, genreId?: string): Promise<SearchResult[]> => {
+    // iTunes official top podcasts RSS
+    // Format: https://itunes.apple.com/fr/rss/toppodcasts/limit=X/genre=Y/json
     const cap = Math.min(limit, 50);
+    const genrePath = genreId ? `/genre=${genreId}` : '';
     const rssResponse = await axios.get<{
       feed: {
         entry: Array<{
@@ -89,7 +91,7 @@ export const podcastIndexService = {
           'im:image': Array<{ label: string; attributes: { height: string } }>;
         }>;
       };
-    }>(`https://itunes.apple.com/fr/rss/toppodcasts/limit=${cap}/json`, {
+    }>(`https://itunes.apple.com/fr/rss/toppodcasts/limit=${cap}${genrePath}/json`, {
       timeout: 10000,
     });