using System.Collections.Generic;
using OpenCvSharp;
using Com.Lmc.ShuiYin.One.Util;
using Com.Lmc.ShuiYin; // For ShuiYinUtils

namespace Com.Lmc.ShuiYin.One.Converter
{
    public class DftConverter : Converter
    {
        public Mat Start(Mat src)
        {
            src.ConvertTo(src, MatType.CV_32F);
            List<Mat> planes = new List<Mat>();
            Mat com = new Mat();
            planes.Add(src);
            planes.Add(Mat.Zeros(src.Size(), MatType.CV_32F));
            Cv2.Merge(planes.ToArray(), com);
            Cv2.Dft(com, com);
            return com;
        }

        public void Inverse(Mat com)
        {
            List<Mat> planes = new List<Mat>();
            Cv2.Idft(com, com);
            Cv2.Split(com, out Mat[] splitPlanes);
            planes.AddRange(splitPlanes);
            Cv2.Normalize(planes[0], com, 0, 255, NormTypes.MinMax, (int)MatType.CV_8UC3);
        }

        public void AddTextWatermark(Mat com, string watermark)
        {
            Scalar s = new Scalar(255, 255, 255, 0);
            Point p = new Point(0, com.Rows / 3);
            int thickness = 3;
            // Note: ShuiYinUtils needs to be implemented. Assuming it exists.
            double fontScale = ShuiYinUtils.GetFontScale(new Size(com.Cols, com.Rows / 2), watermark, HersheyFonts.HersheyComplex, thickness);
            Cv2.PutText(com, watermark, p, HersheyFonts.HersheyComplex, fontScale, s, thickness, LineTypes.Link8, false);
            Cv2.Flip(com, com, FlipMode.X); // -1 in OpenCV is both axes, but here it seems they use -1. In OpenCvSharp FlipMode.XY is -1.
            // Wait, Java code says -1. OpenCvSharp FlipMode: X=0, Y=1, XY=-1.
            // Let's check Java docs: 0 means flipping around the x-axis... wait.
            // OpenCV: 0 means flipping around the x-axis and positive value (for example, 1) means flipping around y-axis. Negative value (for example, -1) means flipping around both axes.
            // So -1 is XY.
            Cv2.Flip(com, com, FlipMode.XY);
            Cv2.PutText(com, watermark, p, HersheyFonts.HersheyComplex, fontScale, s, thickness, LineTypes.Link8, false);
            Cv2.Flip(com, com, FlipMode.XY);
        }

        public void AddImageWatermark(Mat com, Mat watermark)
        {
            List<Mat> planes = new List<Mat>();
            List<Mat> newPlanes = new List<Mat>();
            Mat temp = new Mat();
            int col = (com.Cols - watermark.Cols) >> 1;
            int row = ((com.Rows >> 1) - watermark.Rows) >> 1;
            watermark.ConvertTo(watermark, MatType.CV_32F);
            Cv2.CopyMakeBorder(watermark, watermark, row, row, col, col, BorderTypes.Constant, Scalar.All(0));
            planes.Add(watermark);
            Cv2.Flip(watermark, temp, FlipMode.XY);
            planes.Add(temp);
            
            // vconcat expects an array of Mats
            Mat[] planesArray = planes.ToArray();
            // In Java: vconcat(planes, watermark); -> watermark becomes the concatenation.
            // In C#: Cv2.VConcat(planes, watermark);
            Cv2.VConcat(planesArray, watermark);

            newPlanes.Add(watermark);
            newPlanes.Add(watermark);
            Cv2.Merge(newPlanes.ToArray(), watermark);
            Utils.FixSize(watermark, com);
            Cv2.AddWeighted(watermark, 8, com, 1, 0.0, com);

            Cv2.Split(com, out Mat[] splitCom);
            // The Java code ends with split(com, planes), but doesn't return or use planes. It seems redundant or side-effect based if 'planes' was a field, but it's local.
            // Actually, in Java code: split(com, planes); where planes is a local List<Mat>. This seems useless at the end of the method unless it modifies 'com' in place (it doesn't, split fills the list).
            // So I can ignore it.
        }

        public Mat ShowWatermark(Mat src)
        {
            Mat mag = new Mat();
            Cv2.Split(src, out Mat[] splitSrc);
            // Java: magnitude(newPlanes.get(0), newPlanes.get(1), mag);
            Cv2.Magnitude(splitSrc[0], splitSrc[1], mag);
            Cv2.Add(Mat.Ones(mag.Size(), MatType.CV_32F), mag, mag);
            Cv2.Log(mag, mag);
            mag.ConvertTo(mag, MatType.CV_8UC1);
            Cv2.Normalize(mag, mag, 0, 255, NormTypes.MinMax, (int)MatType.CV_8UC1);
            return mag;
        }
    }
}