refactor: Update playlist service and endpoints for global current playlist management

app/services/playlist.py

@@ -54,9 +54,9 @@ class PlaylistService:
 
         return main_playlist
 
-    async def get_current_playlist(self, user_id: int) -> Playlist:
-        """Get the user's current playlist, fallback to main playlist."""
-        current_playlist = await self.playlist_repo.get_current_playlist(user_id)
+    async def get_current_playlist(self) -> Playlist:
+        """Get the global current playlist, fallback to main playlist."""
+        current_playlist = await self.playlist_repo.get_global_current_playlist()
         if current_playlist:
             return current_playlist
 
@@ -317,6 +317,30 @@ class PlaylistService:
                 user_id,
             )
 
+    # Global current playlist methods
+    async def set_current_playlist_global(self, playlist_id: int) -> Playlist:
+        """Set a playlist as the global current playlist (app-wide)."""
+        playlist = await self.get_playlist_by_id(playlist_id)
+
+        # Unset any existing current playlist globally
+        await self._unset_global_current_playlist()
+
+        # Set new current playlist
+        playlist = await self.playlist_repo.update(playlist, {"is_current": True})
+        logger.info("Set playlist %s as global current playlist", playlist_id)
+        return playlist
+
+    async def unset_current_playlist_global(self) -> None:
+        """Unset the global current playlist (main playlist becomes fallback)."""
+        await self._unset_global_current_playlist()
+        logger.info("Unset global current playlist, main playlist is now fallback")
+
+    async def _unset_global_current_playlist(self) -> None:
+        """Unset any current playlist globally."""
+        current_playlist = await self.playlist_repo.get_global_current_playlist()
+        if current_playlist:
+            await self.playlist_repo.update(current_playlist, {"is_current": False})
+
     async def _unset_current_playlist(self, user_id: int) -> None:
         """Unset the current playlist for a user."""
         current_playlist = await self.playlist_repo.get_current_playlist(user_id)