public IHttpActionResult Post(SongAddRequestModel model)
        {
            if (!this.ModelState.IsValid)
            {
                return this.BadRequest("Invalid model state");
            }

            var song = Mapper.Map<SongAddRequestModel, Song>(model);

            this.Data.Songs.Add(song);
            this.Data.SaveChanges();

            return this.Ok(song.Id);
        }
        public IHttpActionResult Put(int id, SongAddRequestModel model)
        {
            if (!this.ModelState.IsValid)
            {
                return this.BadRequest("Invalid model state");
            }

            var song = this.Data.Songs.All().FirstOrDefault(x => x.Id == id);

            if (song == null)
            {
                return this.NotFound();
            }

            song.Title = model.Title;
            song.Year = model.Year;
            song.Genre = model.Genre;

            this.Data.Songs.Update(song);
            this.Data.SaveChanges();

            return this.Ok(song.Id);
        }