using System;
using Emgu.CV;
using Emgu.CV.Structure;

namespace ImageMinipulation {
    
    public class vanGoghFilters
    {
        /// <summary>
        /// Displays an image in a window and displays the same image but bluerd in a new window
        /// </summary>
        public void One() 
        {
            Mat pic = new Mat();
            Mat gaussianBlur = new Mat();

            pic = CvInvoke.Imread("./img/StarryNight.jpg");
            CvInvoke.GaussianBlur(pic, gaussianBlur, new System.Drawing.Size(15, 15), 5.0);

            CvInvoke.Imshow("starry night", pic);
            CvInvoke.Imshow("blurry night", gaussianBlur);

            CvInvoke.WaitKey();
        }

        /// <summary>
        /// Resizes and image to a predetermined amount
        /// </summary>
        public void Two()
        {
            Mat pic = CvInvoke.Imread("./img/StarryNight.jpg");
            Mat resizedPic = new Mat();

            int height = pic.Rows;
            int width = pic.Cols;

            Console.WriteLine($"Starry Night is : {width} x {height}");

            CvInvoke.Resize(pic, resizedPic, new System.Drawing.Size(400, 500));

            CvInvoke.Imshow("Starry Night", pic);
            CvInvoke.Imshow("resized Night", resizedPic);

            CvInvoke.WaitKey();
        }

        /// <summary>
        /// Rotates an image around the center 45 degrees
        /// </summary>
        public void Three()
        {
            Mat pic = CvInvoke.Imread("./img/StarryNight.jpg");
            Mat rotatedPic = new Mat();
            double angleFortyFive = 45;
            int width = pic.Cols;
            int height = pic.Rows;
            
            System.Drawing.PointF center = new System.Drawing.PointF((width - 1) / 2.0f, (height - 1) / 2.0f);
            Mat rotationMatrix = new Mat();

            CvInvoke.GetRotationMatrix2D(center, angleFortyFive, 1.0, rotationMatrix);
            CvInvoke.WarpAffine(pic, rotatedPic, rotationMatrix, new System.Drawing.Size(width, height));

            CvInvoke.Imshow("Rotated Night", rotatedPic);

            CvInvoke.WaitKey();
        }

        /// <summary>
        /// Changing the color of pixels inside a range to new colors
        /// </summary>
        public void Four()
        {
            Mat pic = CvInvoke.Imread("./img/StarryNight.jpg");
            Image<Bgr, byte> convertPic = pic.ToImage<Bgr, byte>();

            int width = pic.Cols;
            int height = pic.Rows;

            var image = convertPic.InRange(new Bgr(75, 0, 0), new Bgr(255, 125, 125));

            for (int i = 0; i < image.Rows; i++)
            {
                for (int j = 0; j < image.Cols; j++)
                {
                    var num = image[i, j];

                    if (num.Intensity > 0)
                    {
                        convertPic[i, j] = new Bgr(convertPic[i, j].MCvScalar.V0 - 50, convertPic[i, j].MCvScalar.V1 + 100, convertPic[i, j].MCvScalar.V2 - 50);                        
                    }

                }
            }
            Mat changedPic = convertPic.Mat;

            CvInvoke.Imshow("Starry Night", pic);
            CvInvoke.Imshow("Color-Shifted Night", changedPic);

            CvInvoke.WaitKey();
        }

        /// <summary>
        /// 
        /// </summary>
        public void Five()
        {
            Mat pic = CvInvoke.Imread("./img/StarryNight.jpg");

            /// This is a 3D matrix, and we will be using a process called convoluion
            /// Convolution is the application of a kernel to each individual pixal and it's surrounding pixels
            /// then you take that value and put it back in the pixel and some effect happens depending on the valuse
            /// in the kernel
            /// A new convoluted kernal can be looked up for the effect you want (this kernal is basic sharpen)
            float[,] kernalArray = new float[3, 3]
            {
                {  0, -1,  0},
                { -1,  5, -1},
                {  0, -1,  0}
            };

            ConvolutionKernelF kernal = new ConvolutionKernelF(kernalArray);

            Mat filteredPic = new Mat();
            pic.CopyTo(filteredPic);

            CvInvoke.Filter2D(pic, filteredPic, kernal, new System.Drawing.Point(0, 0));

            CvInvoke.Imshow("Convoluted Night", filteredPic);

            CvInvoke.WaitKey();
        }
    }
}