using LibationFileManager;
using NAudio.Lame;
using System;
using System.Threading.Tasks;

namespace FileLiberator
{
    public abstract class AudioDecodable : Processable
    {
        public delegate byte[] RequestCoverArtHandler(object sender, EventArgs eventArgs);
        public event RequestCoverArtHandler RequestCoverArt;
        public event EventHandler<string> TitleDiscovered;
        public event EventHandler<string> AuthorsDiscovered;
        public event EventHandler<string> NarratorsDiscovered;
        public event EventHandler<byte[]> CoverImageDiscovered;
        public abstract Task CancelAsync();

        protected LameConfig GetLameOptions(Configuration config)
        {
			LameConfig lameConfig = new()
			{
				Mode = MPEGMode.Mono,
				Quality = config.LameEncoderQuality,
                OutputSampleRate = (int)config.MaxSampleRate
			};

			if (config.LameTargetBitrate)
            {
                if (config.LameConstantBitrate)
                    lameConfig.BitRate = config.LameBitrate;
                else
                {
                    lameConfig.ABRRateKbps = config.LameBitrate;
                    lameConfig.VBR = VBRMode.ABR;
                    lameConfig.WriteVBRTag = true;
                }
            }
            else
            {
                lameConfig.VBR = VBRMode.Default;
                lameConfig.VBRQuality = config.LameVBRQuality;
                lameConfig.WriteVBRTag = true;
            }
            return lameConfig;
        }
        protected void OnTitleDiscovered(string title) => OnTitleDiscovered(null, title);
        protected void OnTitleDiscovered(object _, string title)
		{
            Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(TitleDiscovered), Title = title });
            TitleDiscovered?.Invoke(this, title);
		}

        protected void OnAuthorsDiscovered(string authors) => OnAuthorsDiscovered(null, authors);
        protected void OnAuthorsDiscovered(object _, string authors)
		{
            Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(AuthorsDiscovered), Authors = authors });
            AuthorsDiscovered?.Invoke(this, authors);
		}

        protected void OnNarratorsDiscovered(string narrators) => OnNarratorsDiscovered(null, narrators);
        protected void OnNarratorsDiscovered(object _, string narrators)
		{
            Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(NarratorsDiscovered), Narrators = narrators });
            NarratorsDiscovered?.Invoke(this, narrators);
		}

        protected byte[] OnRequestCoverArt()
		{
            Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(RequestCoverArt) });
            return RequestCoverArt?.Invoke(this, new());
        }

        protected void OnCoverImageDiscovered(byte[] coverImage)
		{
            Serilog.Log.Logger.Debug("Event fired {@DebugInfo}", new { Name = nameof(CoverImageDiscovered), CoverImageBytes = coverImage?.Length });
            CoverImageDiscovered?.Invoke(this, coverImage);
        }
    }
}