public ActionResult AddTrack(long playlistId, string id)
        {
            if (!ModelState.IsValid)
            {
                return(View("View"));
            }

            var track = trackProvider.LookupTrack(id);

            if (track == null)
            {
                return(new HttpStatusCodeResult(400));
            }

            var albumArtUrl = albumArtProvider.Find(track.Artist + " " + track.Title);

            track.CoverArtUrl = albumArtUrl;

            track = playlistManager.AddTrackToPlaylist(
                playlistId,
                track
                );

            if (track == null)
            {
                return(new HttpStatusCodeResult(400, "You can not add a song that is already in the list"));
            }
            var trackCount = playlistManager.ReadPlaylist(playlistId).PlaylistTracks.Where(p => p.PlayedAt == null).ToList().Count;

            return(Json(trackCount, JsonRequestBehavior.AllowGet));
        }
        public IHttpActionResult AddTrack(long playlistId, string trackId)
        {
            var track = trackProvider.LookupTrack(trackId);

            if (track == null)
            {
                return(NotFound());
            }

            var albumArtUrl = albumArtProvider.Find(track.Artist + " " + track.Title);

            track.CoverArtUrl = albumArtUrl;

            track = playlistManager.AddTrackToPlaylist(
                playlistId,
                track
                );

            if (track == null)
            {
                return(NotFound());
            }

            return(Ok(track));
        }