Update app.py

app.py

@@ -220,17 +220,21 @@ async def get_playlist_info(
     """
     Fetches paginated items from a playlist or user profile.
     Strictly enforces a maximum of 50 items per request and provides a next_page URL.
+    Includes sanitization for lazy-loaded SoundCloud tracks.
     """
+    # 1. Validate inputs
     if start < 1:
         raise HTTPException(status_code=400, detail="'start' must be 1 or greater.")
     if end < start:
         raise HTTPException(status_code=400, detail="'end' must be greater than or equal to 'start'.")
 
+    # 2. Enforce a hard limit of 50 items per request
     requested_count = end - start + 1
     if requested_count > 50:
         end = start + 49
         requested_count = 50
 
+    # Rate Limiting
     client_ip = get_client_ip(request)
     is_allowed, remaining = check_rate_limit(client_ip)
     
@@ -254,25 +258,45 @@ async def get_playlist_info(
         "ignoreerrors": True,
         "cachedir": "/tmp/yt-dlp-cache",
         "js-runtimes": "node",
+        # Pass the strictly clamped pagination settings to yt-dlp
         "playliststart": start,
         "playlistend": end
     }
     
-    with YoutubeDL(ydl_options) as ytdl:
+    with YoutubeDL(ydl_options) as ydl:
         try:
             response = ytdl.extract_info(url, download=False)
             if not response:
                 raise HTTPException(status_code=404, detail="Playlist or profile not found.")
             
+            # Extract entries safely
             raw_entries = response.get("entries") or []
-            valid_entries = [e for e in raw_entries if e is not None]
+            valid_entries = []
+            
+            # --- THE FIX: Sanitize SoundCloud URLs ---
+            for e in raw_entries:
+                if e is not None:
+                    track_url = e.get("url", "")
+                    
+                    # Intercept lazy-loaded API URLs and normalize them
+                    if "api-v2.soundcloud.com/tracks/" in track_url:
+                        track_id = track_url.split("/")[-1].split("?")[0]
+                        e["url"] = f"https://api.soundcloud.com/tracks/{track_id}"
+                        
+                    valid_entries.append(e)
 
+            # 3. Determine if there is a next page
             next_page_url = None
+            
             if len(raw_entries) >= requested_count:
                 next_start = end + 1
                 next_end = next_start + 49
+                
+                # Safely encode the target URL
                 encoded_url = urllib.parse.quote(url)
                 base_url = str(request.base_url).rstrip('/')
+                
+                # Construct the ready-to-use next_page URL for the client
                 next_page_url = f"{base_url}/api/playlist?url={encoded_url}&start={next_start}&end={next_end}"
 
             clean_response = {
@@ -300,6 +324,7 @@ async def get_playlist_info(
                 detail=repr(e),
                 headers={"Cache-Control": "no-store, max-age=0"},
             )
+            
 
 @app.get("/api/rate-limit-status")
 async def get_rate_limit_status(request: Request):