using LibVLCSharp.Shared;
using TechMedia.Core.Backend;
using TechMedia.Core.Model;

namespace TechMedia.Backend.Vlc;

public class VlcAudioBackend : IAudioBackend
{
    private readonly LibVLC _libVlc;
    private readonly MediaPlayer _player;
    private readonly Dictionary<IProgress<float>, EventHandler<MediaPlayerPositionChangedEventArgs>> _progressReporters = new();

    public VlcAudioBackend()
    {
        LibVLCSharp.Shared.Core.Initialize();
        _libVlc = new LibVLC();
        _player = new MediaPlayer(_libVlc);
    }

    public void JustPlay()
    {
        _player.Play();
    }

    public void PlayFile(string filename)
    {
        //_player.Stop();
        var media = new Media(_libVlc, filename);
        _player.Media = media;
        
        media.Dispose();
        
        _player.Play();
        //_player.Position = 0.97f;
    }

    public async Task<Track?> GetFileMetadata(string filename)
    {
        using var media = new Media(_libVlc, filename);
        await Task.Run(async () => await media.Parse());
        if (media.Duration <= 0)
        {
            return null;
        }

        return new Track
        {
            Title = media.Meta(MetadataType.Title),
            Album = media.Meta(MetadataType.Album),
            AlbumArt = media.Meta(MetadataType.ArtworkURL),
            Duration = media.Duration,
            Filename = filename
        };
    }

    public void StopPlayback()
    {
        _player.Stop();
    }

    public void RegisterProgressWatcher(IProgress<float> reporter)
    {
        void Handler(object? _, MediaPlayerPositionChangedEventArgs args)
        {
            reporter.Report(args.Position);
        }

        _player.PositionChanged += Handler;
        _progressReporters.Add(reporter, Handler);
    }

    public void RemoveProgressWatcher(IProgress<float> reporter)
    {
        if (_progressReporters.ContainsKey(reporter))
        {
            _player.PositionChanged -= _progressReporters[reporter];
            _progressReporters.Remove(reporter);
        }
    }

    public void RegisterTrackEndHandler(EventHandler<EventArgs> onEndReached)
    {
        _player.EndReached += onEndReached;
    }
}