/// <summary>
/// Handles user input and programmatic changes for viewed songs and selected song
/// </summary>
/// <param name="sender"></param>
/// <param name="args">Input0: CurrentPlaylist.AllSongs, Input1: CurrentPlaylist.CurrentSong, Input2: CurrentPlaylist.WannaSong, Input3: lbxSongs.SelectedIndex</param>
/// <returns>The list of Songs to view on UI.</returns>
private object MicCurrentSongIndex_ConvertRef(object sender, MultiplesInputsConvert4EventArgs args)
{
if (args.Input0 == null)
{
args.Input3 = -1;
return(null);
}
if (args.ChangedValueIndex == 2)
{
return(args.Input0);
}
IEnumerable <Song> allSongs = (IEnumerable <Song>)args.Input0;
Song?currentSong = (Song?)args.Input1;
int index = (int)args.Input3;
if (args.ChangedValueIndex == 3 && index != -1)
{
args.Input2 = RequestSong.Start(allSongs.ElementAt(index));
}
else if (!currentSong.HasValue)
{
args.Input3 = -1;
}
else
{
args.Input3 = allSongs.IndexOf(currentSong.Value);
}
return(allSongs);
}
private object MicException_Convert(object sender, MultiplesInputsConvert4EventArgs args)
{
return(args.Input3 ?? args.Input2 ?? args.Input1 ?? args.Input0);
}
private object MicPlaylists_Convert(object sender, MultiplesInputsConvert4EventArgs args)
{
MultipleInputs4Converter converter = (MultipleInputs4Converter)sender;
if (args.ChangedValueIndex == 0)
{
if (args.OldValue is INotifyCollectionChanged oldList)
{
oldList.CollectionChanged -= OnCollectionChanged;
}
if (args.Input0 is INotifyCollectionChanged newList)
{
newList.CollectionChanged += OnCollectionChanged;
}
}
else if (args.ChangedValueIndex == 1)
{
if (args.OldValue is INotifyCollectionChanged oldList)
{
oldList.CollectionChanged -= OnCollectionChanged;
}
if (args.Input1 is INotifyCollectionChanged newList)
{
newList.CollectionChanged += OnCollectionChanged;
}
}
UpdateAllPlaylists();
if (args.ChangedValueIndex == 3 && args.Input3 != null)
{
args.Input2 = args.Input3;
}
else
{
args.Input3 = args.Input2;
}
return(allPlaylists);
void OnCollectionChanged(object s, NotifyCollectionChangedEventArgs e)
{
UpdateAllPlaylists();
}
void UpdateAllPlaylists()
{
IPlaylist[] newAllPlaylists = ((IEnumerable <ISourcePlaylist>)converter.Input0).ToNotNull()
.Concat(((IEnumerable <IPlaylist>)converter.Input1).ToNotNull()).ToArray();
for (int i = allPlaylists.Count - 1; i >= 0; i--)
{
if (!newAllPlaylists.Contains(allPlaylists[i]))
{
allPlaylists.RemoveAt(i);
}
}
foreach ((int newIndex, IPlaylist playlist) in newAllPlaylists.WithIndex())
{
int oldIndex = allPlaylists.IndexOf(playlist);
if (oldIndex == -1)
{
allPlaylists.Insert(newIndex, playlist);
}
else if (oldIndex != newIndex)
{
allPlaylists.Move(oldIndex, newIndex);
}
}
}
}