using OpenCvSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace PaintDotNet.Adjust
{
    public class EdgeDetectionIntent
    {
        /// <summary>
        /// Log
        /// </summary>
        /// <param name="src"></param>
        /// <param name="dst"></param>
        public static Mat ImageLog(Mat src)
        {
            Mat gray = null;
            Mat gray1 = null;
            Mat dstImage = null;

            try
            {
                gray = new Mat();
                //将原图像转换为灰度图像
                Cv2.CvtColor(src, gray, ColorConversionCodes.BGR2GRAY);

                gray1 = new Mat();
                //先做高斯模糊
                Cv2.GaussianBlur(gray, gray1, new OpenCvSharp.Size(3, 3), 0);

                dstImage = new Mat();
                //拉普拉斯变换
                Cv2.Laplacian(gray1, dstImage, MatType.CV_16S, 3);
                Cv2.ConvertScaleAbs(dstImage, dstImage);
                dstImage.CopyTo(src);
                return src;
            } 
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (gray != null) gray.Dispose();
                if (gray1 != null) gray1.Dispose();
                if (dstImage != null) dstImage.Dispose();
                GC.Collect();
            }
        }

        /// <summary>
        /// Canny
        /// </summary>
        /// <param name="src"></param>
        /// <returns></returns>
        public static Mat ImageCanny(Mat src, List<Base.Args> lists)
        {
            Mat src_gray = null;

            try
            {
                //过滤尺寸(最大/最小)，需要填写数值
                int size1 = 20;
                int size2 = 100;
                //西格玛值
                double SigmaValue = 1.5;
                foreach (Base.Args args in lists)
                {
                    switch (args.key)
                    {
                        case "KernelSize1":
                            size1 = int.Parse(args.Value.ToString());
                            break;
                        case "KernelSize2":
                            size2 = int.Parse(args.Value.ToString());
                            break;
                        case "Sigma":
                            SigmaValue = double.Parse(args.Value.ToString());
                            break;
                    }
                }

                src_gray = new Mat();
                //该算法对噪声敏感，必须降噪
                Cv2.GaussianBlur(src, src_gray, new OpenCvSharp.Size(3, 3), SigmaValue);
                //将原图像转换为灰度图像
                Cv2.CvtColor(src_gray, src_gray, ColorConversionCodes.BGR2GRAY);
                Cv2.Canny(src_gray, src_gray, size1, size2);
                src_gray.CopyTo(src);
                return src;
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally { 
                if(src_gray!=null) src_gray.Dispose();
                GC.Collect();
            }
        }

        /// <summary>
        /// Sobel
        /// </summary>
        /// <param name="src"></param>
        /// <param name="dst"></param>
        public static Mat ImageSobel(Mat src)
        {
            Mat gray = null, xgrad = null, ygrad = null, output = null;
            try
            {
                //转为灰度
                gray = new Mat();
                Cv2.CvtColor(src, gray, ColorConversionCodes.BGR2GRAY);
                MatType m = src.Type();

                //求 X 和 Y 方向的梯度  Sobel  and scharr
                xgrad = new Mat();
                ygrad = new Mat();
                Cv2.Sobel(gray, xgrad, MatType.CV_16S, 1, 0, 3);
                Cv2.Sobel(gray, ygrad, MatType.CV_16S, 0, 1, 3);

                Cv2.ConvertScaleAbs(xgrad, xgrad);//缩放、计算绝对值并将结果转换为8位。不做转换的化显示不了，显示图相只能是8U类型 
                Cv2.ConvertScaleAbs(ygrad, ygrad);

                //加强边缘检测
                //Cv2.Scharr(gray, xgrad, -1, 1, 0, 3);
                //Cv2.Scharr(gray, ygrad, -1, 0, 1, 3);

                output = new Mat(xgrad.Size(), xgrad.Type());
                //图像混合相加(基于权重 0.5)不精确
                //Cv2.AddWeighted(xgrad, 0.5, ygrad, 0.5, 0, output);

                //基于 算法 G=|Gx|+|Gy|    
                int width = xgrad.Cols;
                int hight = xgrad.Rows;

                //基于 G= (Gx*Gx +Gy*Gy)的开方根
                for (int x = 0; x < hight; x++)
                {
                    for (int y = 0; y < width; y++)
                    {
                        int xg = xgrad.At<byte>(x, y);
                        int yg = ygrad.At<byte>(x, y);
                        double v1 = Math.Pow(xg, 2);
                        double v2 = Math.Pow(yg, 2);
                        int val = (int)Math.Sqrt(v1 + v2);
                        if (val > 255) //确保像素值在 0 -- 255 之间
                        {
                            val = 255;
                        }
                        if (val < 0)
                        {
                            val = 0;
                        }
                        byte xy = (byte)val;
                        output.Set<byte>(x, y, xy);
                    }
                }
                output.CopyTo(src);
                return src;
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (gray != null) gray.Dispose();
                if (xgrad != null) gray.Dispose();
                if (ygrad != null) gray.Dispose();
                if (output != null) gray.Dispose();
                GC.Collect();
            }
        }

        /// <summary>
        /// Kirsch
        /// </summary>
        /// <param name="src"></param>
        /// <param name="dst"></param>
        public static Mat ImageKirsch(Mat src)
        { 
            Mat src_gray = null;
            Mat dst = null;
            try
            {
                dst = new Mat();
                src_gray = new Mat();
                Cv2.CvtColor(src, src_gray, ColorConversionCodes.BGR2GRAY);
                List<Mat> dstImages = new List<Mat>();
                for (int i = 0; i < 8; i++)
                {
                    dstImages.Add(new Mat());
                }

                InputArray kernel1 = InputArray.Create<int>(new int[3, 3] { { 5, 5, 5 }, { -3, 0, -3 }, { -3, -3, -3 } });
                InputArray kernel2 = InputArray.Create<int>(new int[3, 3] { { -3, 5, 5 }, { -3, 0, 5 }, { -3, -3, -3 } });
                InputArray kernel3 = InputArray.Create<int>(new int[3, 3] { { -3, -3, 5 }, { -3, 0, 5 }, { -3, -3, 5 } });
                InputArray kernel4 = InputArray.Create<int>(new int[3, 3] { { -3, -3, -3 }, { -3, 0, 5 }, { -3, 5, 5 } });
                InputArray kernel5 = InputArray.Create<int>(new int[3, 3] { { -3, -3, -3 }, { -3, 0, -3 }, { 5, 5, 5 } });
                InputArray kernel6 = InputArray.Create<int>(new int[3, 3] { { -3, -3, -3 }, { 5, 0, -3 }, { 5, 5, -3 } });
                InputArray kernel7 = InputArray.Create<int>(new int[3, 3] { { 5, -3, -3 }, { 5, 0, -3 }, { 5, -3, -3 } });
                InputArray kernel8 = InputArray.Create<int>(new int[3, 3] { { 5, 5, -3 }, { 5, 0, -3 }, { -3, -3, -3 } });

                Cv2.Filter2D(src_gray, dstImages[0], MatType.CV_8U, kernel1);
                Cv2.Filter2D(src_gray, dstImages[1], MatType.CV_8U, kernel2);
                Cv2.Filter2D(src_gray, dstImages[2], MatType.CV_8U, kernel3);
                Cv2.Filter2D(src_gray, dstImages[3], MatType.CV_8U, kernel4);
                Cv2.Filter2D(src_gray, dstImages[4], MatType.CV_8U, kernel5);
                Cv2.Filter2D(src_gray, dstImages[5], MatType.CV_8U, kernel6);
                Cv2.Filter2D(src_gray, dstImages[6], MatType.CV_8U, kernel7);
                Cv2.Filter2D(src_gray, dstImages[7], MatType.CV_8U, kernel8);

                for (int i = 0; i < dstImages.Count(); i++)
                {
                    dstImages[i] = Cv2.Abs(dstImages[i]);
                }

                dst = dstImages[0];
                for (int i = 1; i < dstImages.Count(); i++)
                {
                    Cv2.Max(dst, dstImages[i], dst);
                }
                dst.CopyTo(src);
                return src;
            }
            catch(Exception e)
            {
                throw e;
            }
            finally
            {
                if (src_gray != null) src_gray.Dispose();
                if (dst != null) dst.Dispose();
                GC.Collect();
            }
        }

        /// <summary>
        /// Prewitt
        /// </summary>
        /// <param name="src"></param>
        /// <param name="dst"></param>
        public static Mat ImagePrewitt(Mat src)
        {
            Mat grad_x = null, grad_y = null, gray = null, grad = null,
                abs_grad_x =null, abs_grad_y=null;

            try
            {
                grad_x = new Mat();
                grad_y = new Mat();
                abs_grad_x = new Mat();
                abs_grad_y = new Mat();
                gray = new Mat();

                //将原图像转换为灰度图像
                Cv2.CvtColor(src, gray, ColorConversionCodes.BGR2GRAY);
                //定义卷积核
                InputArray kernelx = InputArray.Create<double>(new double[3, 3] { { 1, 0, -1 }, { 1, 0, -1 }, { 1, 0, -1 } });
                InputArray kernely = InputArray.Create<double>(new double[3, 3] { { -1, -1, -1 }, { 0, 0, 0 }, { 1, 1, 1 } });
                //卷积运算            
                Cv2.Filter2D(gray, grad_x, MatType.CV_16S, kernelx);
                Cv2.Filter2D(gray, grad_y, MatType.CV_16S, kernely);
                //转为8位
                Cv2.ConvertScaleAbs(grad_x, abs_grad_x);
                Cv2.ConvertScaleAbs(grad_y, abs_grad_y);

                grad = new Mat(abs_grad_x.Size(), abs_grad_x.Type());

                //图像混合相加(基于权重 0.5)不精确
                //Cv2.AddWeighted(abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad);

                //基于 算法 G=|Gx|+|Gy|    
                int width = abs_grad_x.Cols;
                int height = abs_grad_x.Rows;

                //基于 G= (Gx*Gx +Gy*Gy)的开方根
                for (int x = 0; x < height; x++)
                {
                    for (int y = 0; y < width; y++)
                    {
                        int xg = abs_grad_x.At<byte>(x, y);
                        int yg = abs_grad_y.At<byte>(x, y);
                        //int val = (int)Math.Sqrt(xg * xg + yg * yg);
                        grad.Set<int>(x, y, Math.Max(xg, yg));
                    }
                }
                grad.CopyTo(src);
                return src;
            }
            catch(Exception e)
            {
                throw e;
            }
            finally
            {
                if (grad_x != null) grad_x.Dispose();
                if (grad_y != null) grad_y.Dispose();
                if (gray != null) gray.Dispose();
                if (grad != null) grad.Dispose();
                if (abs_grad_x != null) abs_grad_x.Dispose();
                if (abs_grad_y != null) abs_grad_y.Dispose();
                GC.Collect();
            }
        }

        /// <summary>
        /// Roberts
        /// </summary>
        /// <param name="src">源</param>
        /// <param name="dst">目标</param>
        public static Mat ImageRoberts(Mat src)
        {
            Mat output = null;
            Mat src_gray = null;
            Mat dstImageX = null;
            Mat dstImageY = null;
            try
            {
                src_gray = new Mat();
                Cv2.CvtColor(src, src_gray, ColorConversionCodes.BGR2GRAY);

                dstImageX = src_gray.Clone();
                dstImageY = src_gray.Clone();
                //Robert算子 X向量
                InputArray kernelRX = InputArray.Create<int>(new int[2, 2] { { -1, 0 }, { 0, 1 } });
                Cv2.Filter2D(src_gray, dstImageX, MatType.CV_16S, kernelRX, new OpenCvSharp.Point(-1, -1), 0);

                ////Robert算子 Y向量
                InputArray kernelRY = InputArray.Create<int>(new int[2, 2] { { 0, -1 }, { 1, 0 } });
                Cv2.Filter2D(src_gray, dstImageY, MatType.CV_16S, kernelRY, new OpenCvSharp.Point(-1, -1), 0);

                Cv2.ConvertScaleAbs(dstImageX, dstImageX);
                Cv2.ConvertScaleAbs(dstImageY, dstImageY);

                output = new Mat(dstImageX.Size(), dstImageY.Type());
                //图像混合相加(基于权重 0.5)不精确
                //Cv2.AddWeighted(dstImageX, 0.5, dstImageY, 0.5, 0, output);

                //基于 算法 G=|Gx|+|Gy|    
                int width = dstImageX.Cols;
                int height = dstImageY.Rows;

                //基于 G= (Gx*Gx +Gy*Gy)的开方根
                for (int x = 0; x < height; x++)
                {
                    for (int y = 0; y < width; y++)
                    {
                        int xg = dstImageX.At<byte>(x, y);
                        int yg = dstImageY.At<byte>(x, y);
                        double v1 = Math.Pow(xg, 2);
                        double v2 = Math.Pow(yg, 2);
                        int val = (int)Math.Sqrt(v1 + v2);
                        if (val > 255) //确保像素值在 0 -- 255 之间
                        {
                            val = 255;
                        }
                        if (val < 0)
                        {
                            val = 0;
                        }
                        byte xy = (byte)val;
                        output.Set<byte>(x, y, xy);
                    }
                }
                output.CopyTo(src);
                return src;
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (src_gray != null) src_gray.Dispose();
                if (dstImageX != null) dstImageX.Dispose();
                if (dstImageY != null) dstImageY.Dispose();
                if (output != null) output.Dispose();
                GC.Collect();
            }
        }

        /// <summary>
        /// Laplacian
        /// </summary>
        /// <param name="src"></param>
        /// <param name="dst"></param>
        public static Mat ImageLaplace(Mat src)
        {
            Mat gray = null, dstImage = null;
            try
            {
                gray = new Mat();
                dstImage = new Mat();
                Cv2.CvtColor(src, gray, ColorConversionCodes.BGR2GRAY);
                Cv2.Laplacian(gray, dstImage, MatType.CV_16S, 1);
                Cv2.ConvertScaleAbs(dstImage, dstImage);
                dstImage.CopyTo(src);
                return src;
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (gray != null) gray.Dispose();
                if (dstImage != null) dstImage.Dispose();
                GC.Collect();
            }
        }
    }
}