using System;
using Kyoo.Models;
using Microsoft.Extensions.Configuration;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using System.Threading.Tasks;
using Kyoo.Controllers.TranscoderLink;

#pragma warning disable 4014

namespace Kyoo.Controllers
{
	public class BadTranscoderException : Exception {}
	
    public class Transcoder : ITranscoder
    {
        private readonly string _transmuxPath;
        private readonly string _transcodePath;

        public Transcoder(IConfiguration config)
        {
            _transmuxPath = config.GetValue<string>("transmuxTempPath");
            _transcodePath = config.GetValue<string>("transcodeTempPath");

            if (TranscoderAPI.init() != Marshal.SizeOf<Models.Watch.Stream>())
	            throw new BadTranscoderException();
        }

        public async Task<Track[]> GetTrackInfo(string path)
        {
            return await Task.Run(() =>
            {
                TranscoderAPI.GetTrackInfo(path, out Track[] tracks);
                return tracks;
            });
        }

        public async Task<Track[]> ExtractSubtitles(string path)
        {
            string output = Path.Combine(Path.GetDirectoryName(path), "Subtitles");
            Directory.CreateDirectory(output);
            return await Task.Run(() => 
            { 
                TranscoderAPI.ExtractSubtitles(path, output, out Track[] tracks);
                return tracks;
            });
        }

        public async Task<string> Transmux(WatchItem episode)
        {
            string folder = Path.Combine(_transmuxPath, episode.Link);
            string manifest = Path.Combine(folder, episode.Link + ".m3u8");
            float playableDuration = 0;
            bool transmuxFailed = false;

            try
            {
                Directory.CreateDirectory(folder);
                Debug.WriteLine("&Transmuxing " + episode.Link + " at " + episode.Path + ", outputPath: " + folder);

                if (File.Exists(manifest))
                    return manifest;
            }
            catch (UnauthorizedAccessException)
            {
                Console.Error.WriteLine($"Access to the path {manifest} is denied. Please change your transmux path in the config.");
                return null;
            }
            Task.Run(() => 
            { 
                transmuxFailed = TranscoderAPI.transmux(episode.Path, manifest.Replace('\\', '/'), out playableDuration) != 0;
            });
            while (playableDuration < 10 || (!File.Exists(manifest) && !transmuxFailed))
                await Task.Delay(10);
            return transmuxFailed ? null : manifest;
        }

        public async Task<string> Transcode(WatchItem episode)
        {
            string folder = Path.Combine(_transcodePath, episode.Link);
            string manifest = Path.Combine(folder, episode.Link + ".m3u8");
            float playableDuration = 0;
            bool transmuxFailed = false;

            try
            {
                Directory.CreateDirectory(folder);
                Debug.WriteLine("&Transcoding " + episode.Link + " at " + episode.Path + ", outputPath: " + folder);

                if (File.Exists(manifest))
                    return manifest;
            }
            catch (UnauthorizedAccessException)
            {
                Console.Error.WriteLine($"Access to the path {manifest} is denied. Please change your transmux path in the config.");
                return null;
            }

            Task.Run(() =>
            {
                transmuxFailed = TranscoderAPI.transcode(episode.Path, manifest.Replace('\\', '/'), out playableDuration) != 0;
            });
            while (playableDuration < 10 || (!File.Exists(manifest) && !transmuxFailed))
                await Task.Delay(10);
            return transmuxFailed ? null : manifest;
        }
    }
}