using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Drawing.Imaging;
using System.Drawing;

namespace WpfApplication2
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            var new_image = AutoCrop(new Bitmap(@"C:\Users\STUDENT\Desktop\old.jpg"));
            new_image.Save(@"C:\Users\STUDENT\Desktop\new.jpg", ImageFormat.Jpeg);
        }

        private void Display(BitmapSource bmpSource)
        {

        }

        private void ApplyDisplayChanges()
        {

        }


        // Returns a byte array containing the rgb values of each pixel
        public byte[][] GetRGB(Bitmap bmp)
        {
            BitmapData bmp_data = bmp.LockBits(new System.Drawing.Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
            IntPtr ptr = bmp_data.Scan0;
            int num_pixels = bmp.Width * bmp.Height, num_bytes = bmp_data.Stride * bmp.Height, padding = bmp_data.Stride - bmp.Width * 3, i = 0, ct = 1;
            byte[] r = new byte[num_pixels], g = new byte[num_pixels], b = new byte[num_pixels], rgb = new byte[num_bytes];
            System.Runtime.InteropServices.Marshal.Copy(ptr, rgb, 0, num_bytes);

            for (int x = 0; x < num_bytes - 3; x += 3)
            {
                if (x == (bmp_data.Stride * ct - padding)) { x += padding; ct++; };
                r[i] = rgb[x]; g[i] = rgb[x + 1]; b[i] = rgb[x + 2]; i++;
            }
            bmp.UnlockBits(bmp_data);
            return new byte[3][] { r, g, b };
        }

        public System.Drawing.Image AutoCrop(Bitmap bmp)
        {
            //Get an array containing the R,G,B components of each pixel
            var pixels = GetRGB(bmp);

            int h = bmp.Height - 1;
            int w = bmp.Width;

            int top    = 0;
            int bottom = h;
            int left   = bmp.Width;
            int right  = 0;

            int white = 0;
            int tolerance = 95; // 95%

            bool prev_color = false;
            for (int i = 0; i < pixels[0].Length; i++)
            {
                int x = (i % (w));
                int y = (int)(Math.Floor((decimal)(i / w)));
                int tol = 255 * tolerance / 100;

                if (pixels[0][i] >= tol && pixels[1][i] >= tol && pixels[2][i] >= tol)
                {
                    white++;
                    right = (x > right && white == 1) ? x : right;
                }
                else
                {
                    left = (x < left && white >= 1) ? x : left;
                    right = (x == w - 1 && white == 0) ? w - 1 : right;
                    white = 0;
                }

                if (white == w)
                {
                    top = (y - top < 3) ? y : top;
                    bottom = (prev_color && x == w - 1 && y > top + 1) ? y : bottom;
                }

                left = (x == 0 && white == 0) ? 0 : left;
                bottom = (y == h && x == w - 1 && white != w && prev_color) ? h + 1 : bottom;

                if (x == w - 1)
                {
                    prev_color = (white < w) ? true : false;
                    white = 0;
                }
            }
            right = (right == 0) ? w : right;
            left = (left == w) ? 0 : left;

            //Crop the image
            Bitmap bmpCrop = bmp.Clone(new System.Drawing.Rectangle(left, top, right - left + 1, bottom - top), bmp.PixelFormat);

            return bmpCrop as Bitmap;
        }





    }
}