//public Operation<PlaylistTrackModel> CreatePlaylistTrack(PlaylistTrackModel model)
//{
// var operation = Operation.Create(() =>
// {
// if (model.PlaylistID == 0)
// {
// // create a new playlist first before creating a playlist track
// }
// var playlistTrack = (from plistTrack in _db.PlaylistTracks where plistTrack.PlaylistID == model.PlaylistID && plistTrack.TrackID == model.TrackID select plistTrack).FirstOrDefault();
// if (playlistTrack != null) throw new Exception("This track is already in your playlist");
// var newPlaylistTrack = model.Create();
// _db.PlaylistTracks.Add(newPlaylistTrack);
// // persist changes to database
// _db.SaveChanges();
// // assign id of newly created playlistTrack to the model
// model.PlaylistTrackID = newPlaylistTrack.PlaylistTrackID;
// return model;
// });
// return operation;
//}
#endregion
#region Update Operations
public Operation <PlaylistModel> UpdatePlaylist(PlaylistModel model)
{
var operation = Operation.Create(() =>
{
var playlist = (from plist in _db.Playlists where plist.PlaylistID == model.PlaylistID select plist).Include("PlaylistTracks.Track").FirstOrDefault();
if (playlist == null)
{
throw new Exception("Playlist not found");
}
model.Update(playlist);
// create any new tracks if they don't exist
//TODO: requires enhancement
var newTracks = new List <Track>();
model.Tracks.ForEach(t =>
{
// if track id is 0 then it must be a new track
if (t.TrackID == 0)
{
newTracks.Add(t.Create());
}
});
// only add if tehre are any tracks
if (newTracks.Count > 0)
{
_db.Tracks.AddRange(newTracks);
}
// update any changes to existing tracks
var tracks = playlist.PlaylistTracks.Select(plistTrack => { return(plistTrack.Track); }).ToList();
tracks.ForEach(track =>
{
var trackModel = model.Tracks.Where(trackM => trackM.TrackID == track.TrackID).FirstOrDefault();
if (trackModel != null)
{
trackModel.Update(track);
}
});
// persist changes to database
_db.SaveChanges();
// add newly added tracks to playlisttracks
var playlistTracks = newTracks.Select(t =>
{
var playlistTrack = new PlaylistTrack()
{
PlaylistID = playlist.PlaylistID,
TrackID = t.TrackID
};
return(playlistTrack);
}).ToList();
_db.PlaylistTracks.AddRange(playlistTracks);
// persist changes to database
_db.SaveChanges();
// get all tracks afresh
var allTracks = (from plist in _db.PlaylistTracks
where plist.PlaylistID == model.PlaylistID
join track in _db.Tracks on plist.TrackID equals track.TrackID
select track).ToList();
// project out trackmodel
model.Tracks = allTracks.Select(t => { return(new TrackModel(t)); }).ToList();
return(model);
});
return(operation);
}