private void InsertSongToAlbum(ISong song, IAlbum album)
{
if (this.media.FirstOrDefault(a => a is IAlbum && a == album) == null)
{
throw new ArgumentException("The album does not exist in the database.");
}
if (this.media.FirstOrDefault(s => s is ISong && s == song) == null)
{
throw new ArgumentException("The song does not exist in the database.");
}
album.AddSong(song);
this.Printer.PrintLine(string.Format("The song {0} has been added to the album {1}.", song.Title, album.Title));
}