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.Threading;



namespace CRCBreaker

{

    /// <summary>

    /// Interaction logic for MainWindow.xaml

    /// </summary>

    public partial class MainWindow : Window

    {

        CRC16 c16;

        CRC16CCITT c162;



        Thread thdC1;

        Thread thdC2;



        public MainWindow()

        {

            InitializeComponent();

            c16 = new CRC16();

            c162 = new CRC16CCITT( CRC16CCITT.InitialCrcValue.Zeros);



            tCRC16Poly.Text = "0x" + c16.poly.ToString("X");

            tCRC162Poly.Text = "0x"+c162.poly.ToString("X");

            tCRC162IV.Text = "0x"+c162.initialValue.ToString("X");

        }



        private void button1_Click(object sender, RoutedEventArgs e)

        {

            c16.poly = Parse(tCRC16Poly.Text);

            c162.poly = Parse(tCRC162Poly.Text);

            c162.initialValue = Parse(tCRC162IV.Text);



            tCRC16.Text = Visualize(c16.ComputeChecksumBytes(buffer()));

            tCRC162.Text = Visualize(c162.ComputeChecksumBytes(buffer()));

        }



        private ushort Parse(string s)

        {

            if (s.StartsWith("0x"))

            {

                return ushort.Parse(s.Substring(2), System.Globalization.NumberStyles.HexNumber);

            }

            else

                return ushort.Parse(s);

        }



        private byte[] buffer()

        {

            string[] rawData = tData.Text.Trim().Split(' ');

            byte[] buffer = new byte[rawData.Length];

            for (int i = 0; i < rawData.Length; i++)

            {

                buffer[i] = byte.Parse(rawData[i], System.Globalization.NumberStyles.HexNumber);

            }

            return buffer;

        }



        private string Visualize(byte[] buffer)

        {

            StringBuilder sb = new StringBuilder();

            for (int i = 0; i < buffer.Length; i++)

            {

                sb.Append(buffer[i].ToString("X2"));

                if (i < buffer.Length - 1)

                    sb.Append(" ");

            }

            return sb.ToString();

        }



        private void btnGuess1_Click(object sender, RoutedEventArgs e)

        {

            tCRC16Poly.Text = ushort.MinValue.ToString("X");



            thdC1 = new Thread(new ParameterizedThreadStart(Guess1));

            thdC1.IsBackground = true;

            thdC1.Start(buffer());

        }



        private void btnGuess2_Click(object sender, RoutedEventArgs e)

        {

            thdC2 = new Thread(new ParameterizedThreadStart(Guess2));

            thdC2.IsBackground = true;

            thdC2.Start(buffer());

        }



        private void Guess1(object o)

        {

            byte[] ok = new byte[] { 0xf7, 0x1a };

            byte[] buffer = (byte[]) o;

            try

            {

                for (ushort crc_poly = ushort.MinValue; crc_poly < ushort.MaxValue; crc_poly++)

                {

                    c16.poly = crc_poly++;

                    c16.GenTable(c16.poly);



                    byte[] hash = c16.ComputeChecksumBytes(buffer);



                    tCRC16Poly.Dispatcher.BeginInvoke(new Action(() =>

                        {

                            tCRC16Poly.Text = "0x" + (crc_poly).ToString("X");

                            tCRC16.Text = Visualize(hash);

                        }));



                    if (hash.Equals(ok)) break;

                    if (hash[0] == ok[0] && hash[1] == ok[1]) break;

                    if (hash[0] == ok[1] && hash[1] == ok[0]) break;



                    Thread.Sleep(5);



                    if (crc_poly == ushort.MaxValue) break;

                }

            }

            catch

            {



            }

        }



        private void Guess2(object o)

        {

            byte[] ok = new byte[] { 0xf7, 0x1a };

            byte[] buffer = (byte[])o;

            try

            {

                for(ushort ccitt_poly = 1; ccitt_poly <= ushort.MaxValue; ccitt_poly++)

                {

                    for (ushort ccitt_iv = ushort.MinValue; ccitt_iv <= ushort.MaxValue; ccitt_iv++)

                    {

                        c162.initialValue = ccitt_iv;

                        c162.poly = ccitt_poly;

                        c162.GenTable(ccitt_iv, ccitt_poly);



                        byte[] hash = c162.ComputeChecksumBytes(buffer);



                        tCRC162Poly.Dispatcher.BeginInvoke(new Action(() =>

                        {

                            tCRC162Poly.Text = "0x" + ccitt_poly.ToString("X");

                            tCRC162IV.Text = "0x" + ccitt_iv.ToString("X");

                            tCRC162.Text = Visualize(hash);

                        }));



                        if (hash.Equals(ok)) break;

                        if (hash[0] == ok[0] && hash[1] == ok[1]) break;

                        if (hash[0] == ok[1] && hash[1] == ok[0]) break;



                        Thread.Sleep(5);



                        if (ccitt_iv == ushort.MaxValue) break;

                    }

                    if (ccitt_poly == ushort.MaxValue) break;

                }

            }

            catch

            {



            }

        }



        private void btnCalc_Click(object sender, RoutedEventArgs e)

        {



            DateTime d = DateTime.Now; ;

            if (tCRC16.Text != "")

            {

                d = new DateTime(1970, 1, 1).AddSeconds(double.Parse(tCRC16.Text));

            }

            else if (tCRC162.Text != "")

            {

                d = new DateTime(1970, 1, 1).AddSeconds(double.Parse(tCRC162.Text));

                Random rr = new Random((int)d.Ticks);

                byte[] zbuffer = new byte[334];

                rr.NextBytes(zbuffer);

                tData.Text = See(zbuffer);

                return;

            }

            else

                d = dpTime.SelectedDate.Value.AddHours(double.Parse(tH.Text)).AddMinutes(double.Parse(tM.Text)).AddSeconds(double.Parse(tS.Text));

            DateTime k = TimeZoneInfo.ConvertTimeFromUtc(d.ToUniversalTime(), TimeZoneInfo.FindSystemTimeZoneById("Korea Standard Time"));

            Random r = new Random((int)k.Ticks);

            byte[] buffer = new byte[334];

            r.NextBytes(buffer);

            tData.Text = See(buffer);

        }



        public static string See(byte[] buffer)

        {

            StringBuilder sb = new StringBuilder();

            int rows = (int)Math.Ceiling(buffer.Length / 16.0);

            for (int i = 0; i < rows; i++)

            {

                StringBuilder text = new StringBuilder();

                for (int col = 0; col < 16; col++)

                {

                    int pos = col + (i * 16);

                    if (pos < buffer.Length)

                    {

                        sb.Append(buffer[pos].ToString("X2"));

                        if (buffer[pos] > 32 && buffer[pos] < 126)

                            text.Append((char)buffer[pos]);

                        else

                            text.Append(".");

                    }

                    else

                    {

                        sb.Append("  ");

                        text.Append(" ");

                    }

                    sb.Append(" ");

                }

                sb.Append("    ");

                sb.AppendLine(text.ToString());

            }

            return sb.ToString();

        }

    }

}