using axXez.TS3.Audio;
using axXez.TS3.Protocol;
using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

namespace axXez.TS3
{
    /// <summary>
    /// High-level TeamSpeak voice connection. Extends <see cref="VoiceClient"/> with audio playback
    /// via <see cref="AudioPlayer"/>.
    /// The counterpart to <see cref="ServerConnection"/> for the UDP voice protocol.
    /// </summary>
    public class VoiceConnection : VoiceClient, IDisposable
    {
        private readonly AudioPlayer _player;

        /// <summary>Handler raised when the current audio track finishes playing.</summary>
        public delegate void VoiceConnectionTrackEndedHandler(VoiceConnection sender);

        /// <summary>Raised when the current audio track finishes playing.</summary>
        public event VoiceConnectionTrackEndedHandler OnTrackEnded;

        public bool IsPlaying => _player.IsPlaying;
        public bool IsPaused => _player.IsPaused;
        public bool IsStreaming => _player.IsStreaming;
        public TimeSpan Position => _player.Position;
        public TimeSpan Duration => _player.Duration;

        public float Volume
        {
            get => _player.Volume;
            set => _player.Volume = value;
        }

        /// <summary>
        /// Creates a new <see cref="VoiceConnection"/>.
        /// Throws <see cref="InvalidOperationException"/> if ffmpeg or yt-dlp are not installed.
        /// </summary>
        public VoiceConnection(string host, int port = 9987, string nickname = "Bot", VoiceIdentity identity = null, VoiceClientOptions options = null)
            : base(host, port, nickname, identity, options)
        {
            _player = new AudioPlayer(this);

            OnDisconnected += _ => _player.Stop();
            _player.TrackEnded += () => OnTrackEnded?.Invoke(this);
            _player.Error += ex => GlobalLogger.LogError("VoiceConnection", $"Audio error in [{Nickname}]", ex);
        }

        /// <summary>Sends a graceful disconnect to the server and stops the voice client.</summary>
        public new void Stop()
        {
            if (State == VoiceClientState.Connected)
                Disconnect();
            else
                base.Stop();
        }

        /// <summary>Converts <paramref name="filePath"/> via ffmpeg and plays it.</summary>
        public Task PlayFileAsync(string filePath, CancellationToken ct = default)
            => _player.PlayFileAsync(filePath, ct);

        /// <summary>Resolves a YouTube URL via yt-dlp and streams the audio.</summary>
        public async Task PlayYouTubeAsync(string url, IReadOnlyList<string> extraArgs = null, CancellationToken ct = default)
        {
            string direct = await YtDlp.ResolveAsync(url, extraArgs, ct);
            _player.PlayStream(direct);
        }

        /// <summary>Streams audio from a direct URL via ffmpeg.</summary>
        public void PlayStream(string url)
            => _player.PlayStream(url);

        public void PausePlayback()
            => _player.Pause();

        public void ResumePlayback()
            => _player.Resume();

        public void StopPlayback()
            => _player.Stop();

        public void Seek(TimeSpan position)
            => _player.Seek(position);

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