using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace PaintDotNet.GeneralAnalysis.Artwork
{
    internal class ImageTools
    {
        public enum OverlapType
        {
            CENTER = 0,  //中间重叠
            TOPLEFT = 1, //左上角
        }

        /// <summary>
        /// Bitmap裁剪
        /// </summary>
        /// <param name="src">原图</param>
        /// <param name="cropRect">选择区域</param>
        /// <returns></returns>
        public static Bitmap Crop(Bitmap src, Rectangle cropRect)
        {
            Bitmap target = new Bitmap(cropRect.Width, cropRect.Height);
            using (Graphics g = Graphics.FromImage(target))
            {
                g.DrawImage(src, new Rectangle(0, 0, target.Width, target.Height),
                      cropRect,
                      GraphicsUnit.Pixel);
            }
            return target;
        }

        /// <summary>
        /// 拼合图片
        /// </summary>
        /// <param name="bitmaps"></param>
        /// <param name="width"></param>
        /// <param name="height"></param>
        /// <param name="type"></param>
        /// <returns></returns>
        public static Bitmap Overlap(Bitmap[] bitmaps, int width, int height,  OverlapType type)
        {
            Bitmap bmPhoto = new Bitmap(width, height, PixelFormat.Format32bppArgb);
            float x = 0;
            float y = 0;
            //load the Bitmap into a Graphics object 
            Graphics grPhoto = Graphics.FromImage(bmPhoto);
            //Set the rendering quality for this Graphics object
            grPhoto.SmoothingMode = SmoothingMode.AntiAlias;//清除锯齿的呈现
                                                            //haix
            for (int i = 0; i < bitmaps.Length; i++)
            {
                Bitmap img = bitmaps[i];
                if (img == null)
                {
                    continue;
                }
                if (type == OverlapType.CENTER)
                {
                    x = (width - img.Width) / 2.0f;
                    y = (height - img.Height) / 2.0f;
                }

                grPhoto.DrawImage(img, new PointF(x, y));
            }

            return bmPhoto;
        }

        /// <summary>
        /// 生成位置导航窗口图像
        /// </summary>
        /// <param name="bitmap"></param>
        /// <param name="width"></param>
        /// <param name="height"></param>
        /// <param name="pointF"></param>
        /// <returns></returns>
        public static Bitmap CreatView(Bitmap bitmap, int width, int height, PointF pointF)
        {
            Bitmap bmPhoto = new Bitmap(width, height);
            for (int y = 0; y < bmPhoto.Height; y++)
            {
                for (int x = 0; x < bmPhoto.Width; x++)
                {
                    bmPhoto.SetPixel(x, y, Color.FromArgb(0, 0, 0));
                }
            }
            Graphics grPhoto = Graphics.FromImage(bmPhoto);
            //Set the rendering quality for this Graphics object
            grPhoto.SmoothingMode = SmoothingMode.AntiAlias;//清除锯齿的呈现
            grPhoto.DrawImage(bitmap, pointF);

            return bmPhoto;
        }

        /// <summary>
        /// 任意角度旋转
        /// </summary>
        /// <param name="bmp">原始图Bitmap</param>
        /// <param name="angle">旋转角度</param>
        /// <returns></returns>
        public static Bitmap RotateFlip(Bitmap bmp, float angle)
        {
            int w = bmp.Width + 2;
            int h = bmp.Height + 2;

            Bitmap tmp = new Bitmap(w, h);
            Graphics g = Graphics.FromImage(tmp);
            g.DrawImageUnscaled(bmp, 1, 1);
            g.Dispose();

            GraphicsPath path = new GraphicsPath();
            path.AddRectangle(new RectangleF(0f, 0f, w, h));
            Matrix mtrx = new Matrix();
            mtrx.Rotate(angle);
            RectangleF rct = path.GetBounds(mtrx);

            Bitmap dst = new Bitmap((int)rct.Width, (int)rct.Height);
            g = Graphics.FromImage(dst);
            g.TranslateTransform(-rct.X, -rct.Y);
            g.RotateTransform(angle);
            g.InterpolationMode = InterpolationMode.HighQualityBilinear;
            g.DrawImageUnscaled(tmp, 0, 0);
            g.Dispose();

            tmp.Dispose();

            return dst;
        }

        /// <summary>
        /// 调整图片的透明度
        /// </summary>
        /// <param name="src"></param>
        /// <param name="num"></param>
        /// <returns></returns>
        public static Bitmap MakeTransparent(Bitmap src, int num)
        {
            try
            {
                int w = src.Width;
                int h = src.Height;
                Bitmap dstBitmap = new Bitmap(src.Width, src.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
                System.Drawing.Imaging.BitmapData srcData = src.LockBits(new Rectangle(0, 0, w, h), System.Drawing.Imaging.ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
                System.Drawing.Imaging.BitmapData dstData = dstBitmap.LockBits(new Rectangle(0, 0, w, h), System.Drawing.Imaging.ImageLockMode.WriteOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
                unsafe
                {
                    byte* pIn = (byte*)srcData.Scan0.ToPointer();
                    byte* pOut = (byte*)dstData.Scan0.ToPointer();
                    byte* p;
                    int stride = srcData.Stride;
                    int r, g, b;
                    for (int y = 0; y < h; y++)
                    {
                        for (int x = 0; x < w; x++)
                        {
                            p = pIn;
                            b = pIn[0];
                            g = pIn[1];
                            r = pIn[2];
                            pOut[1] = (byte)g;
                            pOut[2] = (byte)r;
                            pOut[3] = (byte)num;
                            pOut[0] = (byte)b;
                            pIn += 4;
                            pOut += 4;
                        }
                        pIn += srcData.Stride - w * 4;
                        pOut += srcData.Stride - w * 4;
                    }
                    src.UnlockBits(srcData);
                    dstBitmap.UnlockBits(dstData);
                    return dstBitmap;
                }
            }
            catch (Exception)
            {
                return null;
            }
        }

        /// <summary>
        /// 两点间距离
        /// </summary>
        /// <param name="startPoint"></param>
        /// <param name="endPoint"></param>
        /// <returns></returns>
        public static double CalcDistance(Point startPoint, Point endPoint)
        {
            int x = System.Math.Abs(endPoint.X - startPoint.X);
            int y = System.Math.Abs(endPoint.Y - startPoint.Y);
            return Math.Sqrt(x * x + y * y);
        }
    }
}