using Accord.Video.DirectShow;
using Accord.Video.FFMPEG;
using log4net;
using Microsoft.Win32;
using Newtonsoft.Json;
using System;
using System.Diagnostics;
using System.Drawing;
using System.IO;
using System.Text;
using System.Threading;
using System.Windows;
using System.Windows.Input;
using Vlc.DotNet.Core;

namespace CameraCaptureDemo
{
    /// <summary>
    /// MainWindow.xaml 的交互逻辑
    /// </summary>
    public partial class MainWindow : Window
    {
        private static readonly ILog log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        // 已经打开文件
        private string _fileName = "";
        // 暂停
        private volatile bool _pause = false;

        #region USB摄像头相关
        // 获取视频采集设备
        protected VideoFileWriter _videoWriter;
        protected volatile object _lock = new object();
        protected volatile bool _recording = false;
        #endregion

        private VideoCapture _videoCapture;
        private Model.VideoDevice _videoDevice;
        private Model.VideoCapabilities _videoCapabilities;

        public MainWindow()
        {
            InitializeComponent();

            this.Closed += delegate { _videoCapture?.Dispose(); };
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            // 显示摄像头画面，隐藏播放器画面
            this.CameraPanel.Visibility = Visibility.Visible;
            this.VlcPanel.Visibility = Visibility.Collapsed;


            // 初始化摄像头
            InitCamera();

            // 初始化播放器
            InitPlayer();
        }

        /// <summary>
        /// 初始化摄像头
        /// </summary>
        private void InitCamera()
        {
            // 获取视频采集设备
            var filterInfoCollection = new FilterInfoCollection(FilterCategory.VideoInputDevice);
            if (filterInfoCollection.Count > 0)
            {
                // 默认选定第一个摄像头路
                var filterInfo = filterInfoCollection[0];

                VideoCaptureDevice videoCaptureDevice = new VideoCaptureDevice(filterInfo.MonikerString);
                // 分辨率和帧率选定
                videoCaptureDevice.VideoResolution = videoCaptureDevice.VideoCapabilities[0];
                foreach (VideoCapabilities vc in videoCaptureDevice.VideoCapabilities)
                {
                    log.Debug("vc => " + JsonConvert.SerializeObject(vc));

                    /*int vw = vc.FrameSize.Width;
                    int fw = videoCaptureDevice.VideoResolution.FrameSize.Width;
                    int vf = vc.AverageFrameRate;
                    int ff = videoCaptureDevice.VideoResolution.AverageFrameRate;

                    if (vw > fw || (vw == fw && vf > ff))
                    {
                        videoCaptureDevice.VideoResolution = vc;
                    }*/
                    if (vc.FrameSize.Width == 1920 && vc.AverageFrameRate == 30 && vc.MaximumFrameRate == 30)
                    {
                        videoCaptureDevice.VideoResolution = vc;
                    }
                }
                log.Debug("VideoCapabilities => " + JsonConvert.SerializeObject(videoCaptureDevice.VideoResolution));

                _videoDevice = new Model.VideoDevice()
                {
                    // 设备友好名称
                    FriendlyName = filterInfo.Name,
                    // 设备的唯一标识符，用于区分哪个设备
                    MonikerName = filterInfo.MonikerString
                };
                _videoCapabilities = new Model.VideoCapabilities()
                {
                    // 帧宽
                    FrameWidth = videoCaptureDevice.VideoResolution.FrameSize.Width,
                    // 帧高
                    FrameHeight = videoCaptureDevice.VideoResolution.FrameSize.Height,
                    // 平均帧率
                    AverageFrameRate = videoCaptureDevice.VideoResolution.AverageFrameRate,
                    // 最大帧率
                    MaximumFrameRate = videoCaptureDevice.VideoResolution.MaximumFrameRate
                };
                // 初始化视频采集接口
                _videoCapture = new VideoCapture(_videoDevice, _videoCapabilities);
                // 实时显示
                _videoCapture.ImageSourceChanged = p => { CameraPlayer.Source = p; };

                if (!_videoCapture.Start(out string errMsg)) {
                    MessageBox.Show(errMsg);
                    return;
                }
            }
        }

        /// <summary>
        /// 初始化播放器
        /// </summary>
        private void InitPlayer()
        {
            ThreadPool.QueueUserWorkItem(_ => {
                this.Dispatcher.BeginInvoke(new Action(() =>
                {
                    //VLC播放器的安装位置，我的VLC播放器安装在D:\Program Files (x86)\VideoLAN\VLC文件夹下。
                    var currentDirectory = new DirectoryInfo(Directory.GetCurrentDirectory() + @"\VLC\" + (Environment.Is64BitProcess ? "x64" : "x86"));

                    var options = new string[]
                    {
                        //添加日志
                        "--file-logging", "-vvv", "--logfile=/logs/vlc_logs.log"
                        // VLC options can be given here. Please refer to the VLC command line documentation.
                    };
                    // 初始化播放器
                    this.VlcPlayer.SourceProvider.CreatePlayer(currentDirectory, options);
                    this.VlcPlayer.SourceProvider.MediaPlayer.LengthChanged += MediaPlayer_LengthChanged;
                    this.VlcPlayer.SourceProvider.MediaPlayer.TimeChanged += MediaPlayer_TimeChanged;
                    // 初始化进度条
                    this.VlcProgress.MouseMove += VlcProgress_MouseMove;
                    this.VlcProgress.TouchMove += VlcProgress_TouchMove;
                    this.VlcProgress.IsMoveToPointEnabled = true;
                }));
            });
        }

        private void MediaPlayer_TimeChanged(object sender, VlcMediaPlayerTimeChangedEventArgs e)
        {
            this.Dispatcher.BeginInvoke(new Action(() =>
            {
                VlcProgress.Value = VlcPlayer.SourceProvider.MediaPlayer.Time;
                if (_pause)
                {
                    VlcPlayer.SourceProvider.MediaPlayer.Pause();
                }
            }));
        }

        private void MediaPlayer_LengthChanged(object sender, VlcMediaPlayerLengthChangedEventArgs e)
        {
            this.Dispatcher.BeginInvoke(new Action(() =>
            {
                VlcProgress.Maximum = VlcPlayer.SourceProvider.MediaPlayer.Length;
                VlcProgress.TickFrequency = 10;
            }));
        }

        private void VlcProgress_TouchMove(object sender, TouchEventArgs e)
        {
            VlcPlayer.SourceProvider.MediaPlayer.Position = (float)VlcProgress.Value / (float)VlcProgress.Maximum;
            _pause = true;
        }

        private void VlcProgress_MouseMove(object sender, MouseEventArgs e)
        {
            if (e.LeftButton == MouseButtonState.Pressed || e.RightButton == MouseButtonState.Pressed)
            {
                VlcPlayer.SourceProvider.MediaPlayer.Position = (float)VlcProgress.Value / (float)VlcProgress.Maximum;
                _pause = true;
            }
        }

        private void OpenFile_Click(object sender, RoutedEventArgs e)
        {
            var openFileDialog = new OpenFileDialog()
            {
                Filter = "Video File|*.mp4;*.avi;*.mkv;*.ts"
            };
            var result = openFileDialog.ShowDialog();
            if (result == true)
            {
                ThreadPool.QueueUserWorkItem(_ =>
                {
                    _fileName = Path.Combine(Environment.CurrentDirectory, "Videos", DateTime.Now.ToString("yyyyMMdd-HHmmss") + ".mp4"); 
                    Convert(openFileDialog.FileName, _fileName);
                    this.Dispatcher.BeginInvoke(new Action(() =>
                    {
                        this.VlcPlayer.SourceProvider.MediaPlayer.Play(new Uri(_fileName));
                        // this.VlcPlayer.SourceProvider.MediaPlayer.Rate = 0.3f;
                        // this.VlcPlayer.SourceProvider.MediaPlayer.Length;
                    }));
                });
            }
        }

        private void Reload_Click(object sender, RoutedEventArgs e)
        {
            _pause = false;
            if (!string.IsNullOrWhiteSpace(_fileName))
            {
                this.VlcPlayer.SourceProvider.MediaPlayer.Play(new Uri(_fileName));
                // this.VlcPlayer.SourceProvider.MediaPlayer.Rate = 0.3f;
            }
        }

        private void Goon_Click(object sender, RoutedEventArgs e)
        {
            _pause = false;
            VlcPlayer.SourceProvider.MediaPlayer.Play();
        }

        #region FFMPEG

        /// <summary>
        /// 转换视频文件
        /// </summary>
        /// <param name="srcFile"></param>
        /// <param name="destFile"></param>
        /// <returns></returns>
        private string Convert(string srcFile, string destFile)
        {
            Process p = new Process();
            ProcessStartInfo startInfo = new ProcessStartInfo();
            startInfo.FileName = Directory.GetCurrentDirectory() + @"\FFMPEG\" + (Environment.Is64BitProcess ? "x64" : "x86") + "\\" + "ffmpeg.exe";
            startInfo.Arguments = BuildArgs(srcFile, destFile);
            startInfo.UseShellExecute = false; // 不使用系统外壳程序启动进程
            startInfo.CreateNoWindow = true; // 不显示dos程序窗口
            startInfo.RedirectStandardInput = true;
            startInfo.RedirectStandardOutput = true;
            // startInfo.RedirectStandardError = true; // 把外部程序错误输出写入到StandardError流中
            startInfo.WindowStyle = ProcessWindowStyle.Hidden;

            p.StartInfo = startInfo;

            p.Start();
            p.WaitForExit();

            try
            {
                // p.BeginErrorReadLine();
                string rst = p.StandardOutput.ReadToEnd();
                Console.WriteLine(rst);
                string err = p.StandardError.ReadToEnd();
                Console.WriteLine("err => " + err);
            }
            catch { }

            p.Close();
            p.Dispose();


            return destFile;
        }

        private string BuildArgs(string srcFile, string destFile)
        {
            StringBuilder builder = new StringBuilder("");
            //builder.Append(" -hwaccel cuvid"); // 显卡加速
            //builder.Append(" -c:v h264_cuvid"); // 显卡加速
            //builder.Append(" -c:v h264_nvenc"); // 显卡加速
            builder.Append(" -i " + srcFile); // 输入文件
            builder.Append(" -vf \"setpts=5.0*PTS\""); // 慢速
            builder.Append(" -s 1920x1080"); // 分辨率
            /*builder.Append(" -r 60"); // 帧率
            //builder.Append(" -bufsize 1024"); // 码率控制缓冲区大小
            builder.Append(" -b:v 8000k"); // 比特率
            builder.Append(" -pix_fmt yuv444p"); // 内存中展开大小
            builder.Append(" -vcodec h264"); // 解码器*/
            builder.Append(" " + destFile); // 输出文件
            return builder.ToString();
        }
        #endregion

        #region RECORD
        /// <summary>
        /// 录制
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Record_Click(object sender, EventArgs e)
        {
            if (!_recording)
            {
                _fileName = Path.Combine(Environment.CurrentDirectory, "Videos", DateTime.Now.ToString("yyyyMMdd-HHmmss") + ".avi");
                
                if (_videoCapture.BeginRecord(_fileName, out string errMsg))
                {
                    this.Record.Content = "停止";
                } else
                {
                    MessageBox.Show(errMsg);
                }

                // 标记为录制中
                _recording = true;
            }
            else
            {
                // 标记为停止录像
                _recording = false;

                if (_videoCapture.EndRecord(out string videoFile, out string errMsg))
                {
                    this.Record.Content = "录制";

                    ThreadPool.QueueUserWorkItem(_ =>
                    {
                        // 设置转码接收文件
                        string destFile = Path.Combine(Environment.CurrentDirectory, "Videos", DateTime.Now.ToString("yyyyMMdd-HHmmss") + ".mp4");
                        // 开始转码
                        Convert(videoFile, destFile);
                        // 转码文件回传
                        _fileName = destFile;
                        // 预览播放
                        this.Dispatcher.BeginInvoke(new Action(() =>
                        {
                            this.CameraPanel.Visibility = Visibility.Collapsed;
                            this.VlcPanel.Visibility = Visibility.Visible;

                            this.VlcPlayer.SourceProvider.MediaPlayer.Play(new Uri(_fileName));
                            //this.VlcPlayer.SourceProvider.MediaPlayer.Rate = 0.5f;
                        }));
                    });
                }
                else
                {
                    MessageBox.Show(errMsg);
                }
            }
        }
        #endregion

        /// <summary>
        /// 显示播放器画面
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void GotoPlayer_Click(object sender, EventArgs e)
        {
            this.CameraPanel.Visibility = Visibility.Collapsed;
            this.VlcPanel.Visibility = Visibility.Visible;
        }

        /// <summary>
        /// 显示摄像头预览
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void GotoCamera_Click(object sender, RoutedEventArgs e)
        {
            this.CameraPanel.Visibility = Visibility.Visible;
            this.VlcPanel.Visibility = Visibility.Collapsed;
        }
    }
}