using System;
using AForge.Video;
using System.Drawing;
using AForge.Controls;
using System.Threading;
using System.Windows.Forms;
using AForge.Video.DirectShow;
using System.Collections.Generic;

namespace shjxCamera
{
    public class WebCamera2
    {
        #region private fields
        private Bitmap _currFrame;
        #endregion

        #region private properties
        public VideoCaptureDevice VidCapDevice2 { get; set; }
        private VideoSourcePlayer VidPlayer2 { get; set; }
        /// <summary>
        /// 当前画面，相机开启时有效
        /// </summary>
        public Bitmap CurrFrame
        {
            get => VidCapDevice2 is not null ? _currFrame.Clone() as Bitmap : null;
            protected set => _currFrame = value;
        }
        /// <summary>
        /// 摄像头是否已打开
        /// </summary>
        public bool IsOpened
        {
            get
            {
                bool isOpened = false;
                if (VidPlayer2 == null)
                {
                    return isOpened;
                }
                if (VidPlayer2.InvokeRequired)
                {
                    VidPlayer2.Invoke(new Action(() =>
                    {
                        isOpened = VidPlayer2.IsRunning;
                    }));
                }
                else
                {
                    isOpened = VidPlayer2.IsRunning;
                }
                return isOpened;
            }
        }
        #endregion

        #region static
        private static FilterInfoCollection vidCollection;
        public static FilterInfoCollection GetCameras()
        {
            vidCollection = new(FilterCategory.VideoInputDevice);
            return vidCollection;
        }

        public static string GetCameraMoniker(int index)
        {
            return vidCollection[index].MonikerString;
        }

        public static string GetCameraName(int index)
        {
            return vidCollection[index].Name;
        }

        #endregion

        #region events
        /// <summary>
        /// 画面刷新事件
        /// </summary>
        public event NewFrameEventHandler NewFrameEvent;
        #endregion

        #region 构造函数
        /// <summary>
        /// 初始化摄像头
        /// </summary>
        /// <param name="cameraMoniker">摄像头名称</param>
        public WebCamera2(string cameraMoniker)
        {
            VidCapDevice2 = new VideoCaptureDevice(cameraMoniker);
            VidCapDevice2.NewFrame += GetCurrFrame;
            VidPlayer2 = new VideoSourcePlayer
            {
                VideoSource = VidCapDevice2
            };
            _currFrame = null;
        }
        /// <summary>
        /// 初始化摄像头
        /// </summary>
        public WebCamera2()
        {
            VidCapDevice2 = new VideoCaptureDevice();
            VidPlayer2 = new VideoSourcePlayer
            {
                VideoSource = VidCapDevice2
            };
            _currFrame = null;
        }
        #endregion

        #region Camera Operate

        /// <summary>
        /// 连接指定的摄像头，并打开视频信号
        /// </summary>
        /// <param name="cameraMoniker"></param>
        /// <returns></returns>
        public bool OpenCamera(string cameraMoniker)
        {
            this.VidCapDevice2.Source = cameraMoniker;
            VidCapDevice2.NewFrame += this.GetCurrFrame;
            this.VidCapDevice2.Start();
            return this.VidCapDevice2.IsRunning;
        }

        /// <summary>
        /// 打开摄像头
        /// </summary>
        /// <returns></returns>
        public bool OpenCamera()
        {
            if (VidCapDevice2 != null && VidCapDevice2.IsRunning == false)
            {
                VidCapDevice2.NewFrame += NewFrameEvent;
                VidCapDevice2.Start();
            }

            if (VidPlayer2.InvokeRequired)
            {
                VidPlayer2.Invoke(new Action(() =>
                {
                    if (VidPlayer2 != null && !VidPlayer2.IsRunning)
                    {
                        VidPlayer2.Start();
                    }
                }));
            }
            else
            {
                if (VidPlayer2 != null && !VidPlayer2.IsRunning)
                {
                    VidPlayer2.Start();
                }
            }
            return true;
        }

        /// <summary>
        /// 关闭摄像头
        /// </summary>
        public void CloseCamera()
        {
            if (VidCapDevice2 != null && VidCapDevice2.IsRunning)
            {
                VidCapDevice2.SignalToStop();
                VidCapDevice2.WaitForStop();
                //VidCapDevice.Stop();
                VidCapDevice2.NewFrame -= NewFrameEvent;
            }

            if (VidPlayer2.InvokeRequired)
            {
                VidPlayer2.Invoke(new Action(() =>
                {
                    if (VidPlayer2 == null || !VidPlayer2.IsRunning) return;
                    VidPlayer2.SignalToStop();
                    VidPlayer2.WaitForStop();
                }));
            }
            else
            {
                if (VidPlayer2 == null || !VidPlayer2.IsRunning) return;
                VidPlayer2.SignalToStop();
                VidPlayer2.WaitForStop();
            }

        }

        /// <summary>
        /// 拍照
        /// </summary>
        /// <returns></returns>
        public Bitmap GrabImage2()
        {
            Bitmap bmp = null;

            if (VidPlayer2.InvokeRequired)
            {
                VidPlayer2.Invoke(new Action(() =>
                {
                    if (VidPlayer2.IsRunning)
                    {
                        bmp = VidPlayer2.GetCurrentVideoFrame();
                    }
                    else
                    {
                        // 探头未连接，重试
                        int cnt = 0; // 重试10秒
                        while (!VidPlayer2.IsRunning && cnt < 100)
                        {
                            VidPlayer2.Start();
                            Thread.Sleep(100);
                            cnt++;
                            //PublicDatas.LogProgram.Error("摄像头未连接，正在重试" + cnt.ToString());
                        }
                        Thread.Sleep(300);
                        bmp = VidPlayer2.GetCurrentVideoFrame();
                    }
                }));
            }
            else
            {
                if (VidPlayer2.IsRunning)
                {
                    bmp = VidPlayer2.GetCurrentVideoFrame();
                }
                else
                {
                    // 探头未连接，重试
                    int cnt = 0; // 重试10秒
                    while (!VidPlayer2.IsRunning && cnt < 100)
                    {
                        VidPlayer2.Start();
                        Thread.Sleep(100);
                        cnt++;
                        // PublicDatas.LogProgram.Error("摄像头未连接，正在重试" + cnt.ToString());
                    }
                    Thread.Sleep(300);
                    bmp = VidPlayer2.GetCurrentVideoFrame();
                }
            }
            return bmp;
        }
        #endregion

        #region public methods

        /// <summary>
        /// 设置显示摄像头图像区域
        /// </summary>
        /// <param name="parentControl"></param>
        /// <param name="left"></param>
        /// <param name="top"></param>
        /// <param name="width"></param>
        /// <param name="height"></param>
        public void ShowControl(ref Panel parentControl, int left, int top, int width, int height)
        {
            if (VidPlayer2 == null) return;
            parentControl.Controls.Add(VidPlayer2);
            VidPlayer2.Location = new Point(left, top);
            VidPlayer2.Size = new Size(width, height);
            VidPlayer2.Visible = true;
        }

        /// <summary>
        /// 显示摄像头属性设置窗体
        /// </summary>
        /// <param name="parentWindow"></param>
        public void ShowProperties(IntPtr parentWindow)
        {
            VidCapDevice2.DisplayPropertyPage(parentWindow);
        }

        /// <summary>
        /// 设置相机属性值
        /// </summary>
        /// <param name="prop"></param>
        /// <param name="val"></param>
        /// <param name="flags"></param>
        public void SetProperties(CameraControlProperty prop, int val, CameraControlFlags flags)
        {
            VidCapDevice2.SetCameraProperty(prop, val, flags);// 取消自动曝光
        }

        /// <summary>
        /// 读取当前属性值
        /// </summary>
        /// <param name="prop"></param>
        /// <param name="val"></param>
        /// <param name="flags"></param>
        public void GetProperties(CameraControlProperty prop, out int val, out CameraControlFlags flags)
        {
            VidCapDevice2.GetCameraProperty(prop, out val, out flags);
        }

        /// <summary>
        /// 读取相机参数的取值范围
        /// </summary>
        /// <param name="prop"></param>
        /// <param name="minValue"></param>
        /// <param name="maxValue"></param>
        /// <param name="stepSize"></param>
        /// <param name="defaultValue"></param>
        /// <param name="flags"></param>
        public void GetPropertiesRange(CameraControlProperty prop, out int minValue, out int maxValue, out int stepSize, out int defaultValue, out CameraControlFlags flags)
        {
            VidCapDevice2.GetCameraPropertyRange(prop, out minValue, out maxValue, out stepSize, out defaultValue, out flags);
        }

        /// <summary>
        /// 设置视频属性值，亮度、对比度、白平衡、增益等
        /// </summary>
        /// <param name="prop"></param>
        /// <param name="val"></param>
        /// <param name="flags"></param>
        public void SetVideoProcAmpProperties(VideoProcAmpProperty prop, int val, VideoProcAmpFlags flags)
        {
            VidCapDevice2.SetVideoProcAmpProperty(prop, val, flags);
        }

        /// <summary>
        /// 读取当前视频参数
        /// </summary>
        /// <param name="prop"></param>
        /// <param name="val"></param>
        /// <param name="flags"></param>
        public void GetVideoProcAmpProperties(VideoProcAmpProperty prop, out int val, out VideoProcAmpFlags flags)
        {
            VidCapDevice2.GetVideoProcAmpProperty(prop, out val, out flags);
        }

        /// <summary>
        /// 读取视频参数的取值范围
        /// </summary>
        /// <param name="prop"></param>
        /// <param name="minValue"></param>
        /// <param name="maxValue"></param>
        /// <param name="stepSize"></param>
        /// <param name="defaultValue"></param>
        /// <param name="flags"></param>
        public void GetVideoProcAmpPropertiesRange(VideoProcAmpProperty prop, out int minValue, out int maxValue, out int stepSize, out int defaultValue, out VideoProcAmpFlags flags)
        {
            VidCapDevice2.GetVideoProcAmpPropertyRange(prop, out minValue, out maxValue, out stepSize, out defaultValue, out flags);
        }

        /// <summary>
        /// 实时将新的画面存入CurrFrame对象中
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void GetCurrFrame(object sender, NewFrameEventArgs e)
        {
            try
            {
                if (e.Frame != null)
                {
                    CurrFrame = e.Frame;
                }
            }
            catch (Exception)
            {
                // ignored
            }
        }

        #endregion

        #region 未使用
        /// <summary>
        /// 拍照，返回CurrFrame图像
        /// </summary>
        /// <returns></returns>
        //public Bitmap GrabImage2()
        //{
        //    return CurrFrame;
        //}
        /// <summary>
        /// 返回视频支持的分辨率
        /// </summary>
        /// <returns></returns>
        public List<string> GetVideoResolution()
        {
            List<string> resolution = new List<string>();
            foreach (var cap in VidCapDevice2.VideoCapabilities)
            {
                resolution.Add(string.Format("{0} x {1}", cap.FrameSize.Width, cap.FrameSize.Height));
            }
            return resolution;
        }

        /// <summary>
        /// 设定视频的分辨率，index可以通过GetVideoResolution()获取所有支持的分辨率来确定
        /// </summary>
        /// <param name="index">在所有支持分辨率中的序号</param>
        public void SetVideoResolution(int index)
        {
            if (VidCapDevice2.VideoCapabilities.Length > index)
            {
                VidCapDevice2.VideoResolution = VidCapDevice2.VideoCapabilities[index];
            }
        }
        #endregion

        // 抓取一帧图像，截取中间区域，按灰度值过滤后，计算平均RGB值
        public ColorPoint CaptureOne(string captureTag, int size, int gray_min, int gray_max)
        {
            Bitmap bmp = GrabImage22();
            if (bmp is null)
            {
                return new(0, 0, 0, captureTag);
            }
            int cntLow = 0, cntHigh = 0, cntNormal = 0;
            int sumR = 0, sumG = 0, sumB = 0;
            for (int y = bmp.Height / 2 - size / 2; y < bmp.Height / 2 + size / 2; y++)
            {
                for (int x = bmp.Width / 2 - size / 2; x < bmp.Width / 2 + size / 2; x++)
                {
                    Color cc = bmp.GetPixel(x, y);
                    int gray = Math.Min(255, (int)(cc.R * 0.299 + cc.G * 0.587 + cc.B * 0.114));
                    if (gray < gray_min)
                    {
                        cntLow++;
                        continue;
                    }
                    if (gray > gray_max)
                    {
                        cntHigh++;
                        continue;
                    }
                    cntNormal++;
                    sumR += cc.R;
                    sumG += cc.G;
                    sumB += cc.B;
                }
            }
            int avgR = 0, avgG = 0, avgB = 0;
            if (cntNormal > 0)
            {
                avgR = sumR / cntNormal;
                avgG = sumG / cntNormal;
                avgB = sumB / cntNormal;
            }
            // 记录颜色采样信息
            ColorPoint cp = new(avgR, avgG, avgB, captureTag);
            float total = size * size;
            if (!"watch".Equals(captureTag))
            {
                //logger.LogTrace($"<{captureTag}> HSB({cp.Hue,3},{cp.Saturation:F3},{cp.Brightness:F3}), RGBL({cp.R,3},{cp.G,3},{cp.B,3},{cp.Gray,3}), PLMH({total},{cntLow / total:F3},{cntNormal / total:F3},{cntHigh / total:F3}), WH:({bmp.Width},{bmp.Height})");
                //bmp.Save($"Data/{captureTag}.jpg", ImageFormat.Jpeg);
            }
            return cp;
        }

        // 背景底色采样
        public ColorPoint SampleBackground(string taskTag, int threshold_gray, int threshold_hue)
        {
            List<ColorPoint> cps = new List<ColorPoint>();
            for (int i = 0; i < 99; i++)
            {
                cps.Add(Sample($"{taskTag}/000S-{i + 1:D2}", threshold_gray, threshold_hue));
                if (cps.Count >= 5)
                {
                    // 如排序后前三轮或后三轮的色调偏差小于阈值，完成采样
                    ColorPoint[] ar = cps.ToArray();
                    Array.Sort(ar);
                    //Array.Reverse(ar);
                    if (Math.Abs(ar[0].Hue - ar[2].Hue) <= threshold_hue || Math.Abs(ar[2].Hue - ar[4].Hue) <= threshold_hue)
                    {
                        ColorPoint cp = ar[2];
                        return cp;
                    }
                    // 未达标，丢弃最早抓取的帧，继续采样
                    cps.RemoveAt(0);
                }
                Thread.Sleep(100);
            }
            // 背景底色采样达到最大次数
            //logger.LogWarning($"<{taskTag}> 背景底色采样达到最大次数!");
            return cps.Last();
        }

        // 色值采样(抓取n帧图像合并计算)
        public ColorPoint Sample(string prefix, int threshold_gray, int threshold_hue)
        {
            int gray_min = threshold_gray;
            int gray_max = 255 - threshold_gray;
            List<ColorPoint> cps = new List<ColorPoint>();
            for (int i = 0; i < 99; i++)
            {
                string captureTag = $"{prefix}-{i + 1:D2}";
                int size = 200;
                ColorPoint cp = CaptureOne(captureTag, size, gray_min, gray_max);
                // 丢弃亮度过低的帧，继续采样
                if (cp.Gray <= gray_min)
                {
                    Thread.Sleep(100);
                    continue;
                }
                cps.Add(cp);
                if (cps.Count >= 5)
                {
                    // 构建排列的数组
                    ColorPoint[] ar = cps.ToArray();
                    Array.Sort(ar);
                    //Array.Reverse(ar);
                    // 前三帧色调偏差小于等于阈值，取前三帧完成采样
                    if (Math.Abs(ar[0].Hue - ar[2].Hue) <= threshold_hue)
                    {
                        return Merge(ar.Take(3).ToList(), prefix);
                    }
                    // 后三帧色调偏差小于等于阈值，取后三帧完成采样
                    if (Math.Abs(ar[2].Hue - ar[4].Hue) <= threshold_hue)
                    {
                        return Merge(ar.Skip(2).Take(3).ToList(), prefix);
                    }
                    // 未达标，丢弃最早抓取的帧，继续采样
                    cps.RemoveAt(0);
                }
                Thread.Sleep(100);
            }
            // 达到最大采样次数限制，返回最后一次采样结果
            //logger.LogWarning($"<{prefix}> 色值采样达到最大次数!");
            if (cps.Count > 0)
            {
                return cps.Last();
            }
            return new ColorPoint(0, 0, 0, prefix);
        }

        // 合并计算色值
        private static ColorPoint Merge(List<ColorPoint> list, string prefix)
        {
            int n = list.Count;
            if (n == 0)
            {
                return new ColorPoint(0, 0, 0, prefix);
            }
            int sampleR = 0, sampleG = 0, sampleB = 0;
            for (int i = 0; i < n; i++)
            {
                sampleR += list[i].R;
                sampleG += list[i].G;
                sampleB += list[i].B;
            }
            ColorPoint cp = new(sampleR / n, sampleG / n, sampleB / n, prefix);
            //logger.LogInformation($"<{prefix}> HSB:({cp.Hue,3},{cp.Saturation:F3},{cp.Brightness:F3}), Gray:{cp.Gray,3}, RGB:({cp.R,3},{cp.G,3},{cp.B,3})");
            return cp;
        }

        public Bitmap GrabImage22()
        {
            Bitmap bmp = null;
            if (VidPlayer2.InvokeRequired)
            {
                VidPlayer2.Invoke(new Action(() => bmp = VidPlayer2.GetCurrentVideoFrame()));
            }
            else
            {
                bmp = VidPlayer2.GetCurrentVideoFrame();
            }
            return bmp;
        }
    }
}