public void MoveToPrevSong()
{
if (!SongArchive.Any())
{
return;
}
// shrink list of upcoming songs
UpcomingSongs.Insert(0, CurrentSong);
UpcomingSongs.Remove(UpcomingSongs.Last());
// reassign current song (take last song from archive)
CurrentSong = SongArchive.Last();
// update archive
SongArchive.Remove(SongArchive.Last());
}
/// <summary>
/// Switching to previous song is done synchronously
/// since his operation is very cheap (just recombinate songs in collections)
/// </summary>
public Task MoveToPrevSongAsync()
{
if (SongArchive.Any())
{
// shrink list of upcoming songs
UpcomingSongs.Insert(0, CurrentSong);
UpcomingSongs.Remove(UpcomingSongs.Last());
// reassign current song (take last song from archive)
CurrentSong = SongArchive.Last();
// update archive
SongArchive.Remove(SongArchive.Last());
}
return(Task.CompletedTask);
}