using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Drawing;

namespace ddddd
{
    public struct CaptchaSymbol
    {
        public int LenPx;
        public string Name;
    }

    class AntiCaptcha
    {
        Bitmap img = null;

        public static CaptchaSymbol[] CaptchaSymbols = {new CaptchaSymbol{
            LenPx = 14,
            Name = "1",
        }, new CaptchaSymbol{
            LenPx = 32,
            Name = "2",
        }, new CaptchaSymbol{
            LenPx = 31,
            Name = "3",
        }, new CaptchaSymbol{
            LenPx = 27,
            Name = "4",
        }, new CaptchaSymbol{
            LenPx = 38,
            Name = "5",
        }, new CaptchaSymbol{
            LenPx=33,
            Name = "6",
        }, new CaptchaSymbol{
            LenPx=26,
            Name = "7",
        }, new CaptchaSymbol{
            LenPx=40,
            Name = "8",
        }, new CaptchaSymbol{
            LenPx=35,
            Name = "9",
        }, new CaptchaSymbol{
            LenPx = 39,
            Name = "0"}
        };

        Dictionary<string, List<int>> hTable = new Dictionary<string, List<int>>();
        public AntiCaptcha(string URLimg)
        {
            WebClient webClient = new WebClient();
            webClient.Headers.Add("user-agent", "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/535.2 (KHTML like Gecko) Chrome/15.0.874.102 Safari/535.2");
            webClient.DownloadFile(URLimg, "temp.gif");
            this.img = new Bitmap("temp.gif");
        }

        public string GetCode()
        {
            var palette = new Dictionary<Color, int>();
            for (var x = 0; x < img.Width; x++)
            {
                for (var y = 0; y < img.Height; y++)
                {
                    var clr = img.GetPixel(x, y);
                    if (!palette.ContainsKey(clr))
                    {
                        palette.Add(clr, 1);
                    }
                    else
                    {
                        palette[clr] = palette[clr] + 1;
                    }
                }
            }
            var i = 0;
            foreach (var p in palette)
            {
                if (p.Value > 20)
                {
                    var temp = this.ClearBitmap(img, p.Key);
                    temp.Save(String.Format("mask-{0}.bmp", i));
                    i++;
                }
            }

            Bitmap a = new Bitmap("mask-0.bmp");
            for (int j = 1; j <= 5; j++)
            {
                GetPosition(a, 8 * j, 16, j);
            }

            int oldWidth = 0;
            int newWidth = 0;
            int CountPixel = 0;
            string result = null;
            for (int j = 0; j < hTable["width"].Count; j++)
            {
                newWidth = hTable["width"][j];
                CountPixel = CountPixels(a, newWidth, 16, oldWidth);
                if (CountPixel > 0)
                {
                    foreach (CaptchaSymbol si in CaptchaSymbols)
                    {
                        if (si.LenPx == CountPixel)
                        {
                            result += si.Name;
                            break;
                        }

                    }
                }
                oldWidth = hTable["width"][j];

            }

            return result;
        }

        private Bitmap ClearBitmap(Bitmap input, Color clr)
        {
            var result = new Bitmap(input.Width, input.Height);
            for (var x = 0; x < input.Width; x++)
            {
                for (var y = 0; y < input.Height; y++)
                {
                    var color = input.GetPixel(x, y);
                    result.SetPixel(x, y, clr == color ? Color.White : Color.Black);
                }
            }

            return result;
        }

        private int CountPixels(Bitmap img, int Width, int Height, int oldWidth)
        {
            int a = 0;
            for (int y = 0; y < Height; y++)
            {
                for (int x = oldWidth; x < Width; x++)
                {
                    if (img.GetPixel(x, y).R == 0)
                        a++;
                }
            }
            return a;
        }

        private int GetPosition(Bitmap img, int Width, int Height, int j)
        {
            hTable["width"] = new List<int>();
            int OldWidth = j * 8 - 8;
            int MaxWidth = 0;
            int MaxHeight = 0;

            for (var x = 0; x < Width; x++)
            {
                for (var y = 0; y < Height; y++)
                {
                    if (img.GetPixel(x, y).R == 255)
                        MaxHeight++;
                    if (MaxHeight == 16)
                    {
                        hTable["width"].Add(x);
                        break;
                    }
                }
                MaxHeight = 0;

            }
            return MaxWidth;
        }

    }
}