using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Security.Cryptography;
using System.Data.OleDb;

namespace EncyrptedPassword
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            string Username = "", GuessedPasswordHashed = "", CorrectPassword = "", UsernameFromDatabse = "";
            Username = txt_Username.Text;
            GuessedPasswordHashed = GenerateHash(txt_Password.Text);

             GetUsername(ref UsernameFromDatabse, ref CorrectPassword, Username);
            if (GuessedPasswordHashed == CorrectPassword && Username == UsernameFromDatabse)
            {
                Successful frm = new Successful();
                frm.Show();
            }
            else
            {
                txt_Password.Text = "";
                txt_Username.Text = "";
                MessageBox.Show("Please enter correct Username or Password");
            }
        }
        private string GenerateHash(string SourceText)
        {

            UnicodeEncoding Ue = new UnicodeEncoding();
            byte[] ByteSourceText = Ue.GetBytes(SourceText);
            MD5CryptoServiceProvider MD5 = new MD5CryptoServiceProvider();
            byte[] ByteHash = MD5.ComputeHash(ByteSourceText);
            return Convert.ToBase64String(ByteHash);
        }
        private void GetUsername(ref string UsernameFromDatabse, ref string CorrectPassword, string Username)
        {
            clsDBConnector dbConnector = new clsDBConnector();
            OleDbDataReader dr;
            string sqlStr;
            dbConnector.Connect();
            sqlStr = "SELECT        Username, [Password]" +
                  " FROM            Login" +
                  " WHERE        Username = '" + Username + "'";
            dr = dbConnector.DoSQL(sqlStr);
            while (dr.Read())
            {
                UsernameFromDatabse = Convert.ToString(dr[0]);
                CorrectPassword = Convert.ToString(dr[1]);

            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            if (txt_Password.UseSystemPasswordChar == true)
            {
                txt_Password.UseSystemPasswordChar = false;
            }
            else
            {
                txt_Password.UseSystemPasswordChar = true;
            }
        }
    }

}