using System;
using System.Collections.Generic;
using System.Text;
using System.Security;
using System.Security.Cryptography;
using System.IO;
using System.Runtime.InteropServices;

namespace WintecLib
{
    public class Mac
    {
        //MD5不可逆加密
        public static string Md5(string strPassword)
        {
            MD5CryptoServiceProvider hashmd5;
            hashmd5 = new MD5CryptoServiceProvider();
            return BitConverter.ToString(hashmd5.ComputeHash(Encoding.Default.GetBytes(strPassword))).Replace("-", "").ToLower();
        }
        
        /// <summary>
        /// DES解密
        /// </summary>
        /// <param name="Key">密鑰</param>
        /// <param name="Data">數據</param>
        /// <returns>解密后的數據</returns>
        public static byte[] DESDecrypt(byte[] Key, byte[] Data)
        {

            try
            {
                DESCryptoServiceProvider MyServiceProvider = new DESCryptoServiceProvider();

                //計算des加密所采用的算法

                MyServiceProvider.Mode = CipherMode.CBC;

                //計算填充類型
                MyServiceProvider.Padding = PaddingMode.Zeros;

                ICryptoTransform MyTransform = MyServiceProvider.CreateDecryptor(Key, new byte[8] { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 });
                //CryptoStream對象的作用是將數據流連接到加密轉換的流
                MemoryStream ms = new MemoryStream();
                CryptoStream MyCryptoStream = new CryptoStream(ms, MyTransform, CryptoStreamMode.Write);
                //將字節數組中的數據寫入到加密流中
                MyCryptoStream.Write(Data, 0, Data.Length);
                MyCryptoStream.FlushFinalBlock();
                MyCryptoStream.Close();
                byte[] byEncRet = ms.ToArray();
                ms.Close();
                return byEncRet;
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}", ex.Message);
                return new byte[8];
            }



        }
        /// <summary>
        /// DES加密
        /// </summary>
        /// <param name="Key">密鑰</param>
        /// <param name="Data">數據</param>
        /// <returns>加密后的數據</returns>
        public static byte[] DESEncrypt(byte[] Key, byte[] Data)
        {

            try
            {
                DESCryptoServiceProvider MyServiceProvider = new DESCryptoServiceProvider();

                //計算des加密所采用的算法

                MyServiceProvider.Mode = CipherMode.CBC;

                //計算填充類型
                MyServiceProvider.Padding = PaddingMode.Zeros;

                ICryptoTransform MyTransform = MyServiceProvider.CreateEncryptor(Key, new byte[8] { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 });
                //CryptoStream對象的作用是將數據流連接到加密轉換的流
                MemoryStream ms = new MemoryStream();
                CryptoStream MyCryptoStream = new CryptoStream(ms, MyTransform, CryptoStreamMode.Write);
                //將字節數組中的數據寫入到加密流中
                MyCryptoStream.Write(Data, 0, Data.Length);
                MyCryptoStream.FlushFinalBlock();
                MyCryptoStream.Close();
                byte[] byEncRet = ms.ToArray();
                ms.Close();
                return byEncRet;
            }
            catch (Exception ex)
            {
                Console.WriteLine("Exception caught: {0}", ex.Message);
                return new byte[8];
            }
        }

      



        /// <summary>
        /// 對異或后的8位數據進行加密,位數不足8位補0x0
        /// </summary>
        /// <param name="Key">密鑰</param>
        /// <param name="Data">數據</param>
        /// <returns>加密后的數據</returns>
        public static byte[] HCDES(byte[] Key, byte[] Data)
        {
            try
            {
                //創建一個DES算法的加密類
                DESCryptoServiceProvider MyServiceProvider = new DESCryptoServiceProvider();
                MyServiceProvider.Mode = CipherMode.CBC;
                MyServiceProvider.Padding = PaddingMode.None;
                //從DES算法的加密類對象的CreateEncryptor方法,創建一個加密轉換接口對象
                //第一個參數的含義是：對稱算法的機密密鑰(長度為64位,也就是8個字節)
                // 可以人工輸入,也可以隨機生成方法是：MyServiceProvider.GenerateKey();
                //第二個參數的含義是：對稱算法的初始化向量(長度為64位,也就是8個字節)
                // 可以人工輸入,也可以隨機生成方法是：MyServiceProvider.GenerateIV()

                //
                ICryptoTransform MyTransform = MyServiceProvider.CreateEncryptor(Key,Key);// new byte[8] { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 });

                //CryptoStream對象的作用是將數據流連接到加密轉換的流
                MemoryStream ms = new MemoryStream();
                CryptoStream MyCryptoStream = new CryptoStream(ms, MyTransform, CryptoStreamMode.Write);
                //將字節數組中的數據寫入到加密流中


                MyCryptoStream.Write(Data, 0, Data.Length);
                //關閉加密流對象
                byte[] bEncRet = new byte[8];
                // Array.Copy(ms.GetBuffer(), bEncRet, ms.Length);
                bEncRet = ms.ToArray(); // MyCryptoStream關閉之前ms.Length 為8， 關閉之后為16

                MyCryptoStream.FlushFinalBlock();
                MyCryptoStream.Close();
                byte[] bTmp = ms.ToArray();
                ms.Close();


                // return bEncRet;
                return bTmp;// 
            }
            catch (Exception ex)
            {
                Console.WriteLine("HCDES Exception Caught, Exception = {0}", ex.Message);
                return new byte[8];
            }

        }


        /// <summary>
        /// Mac驗證碼的數據生成講數據分為8位1組進行異或后加密
        /// </summary>
        /// <param name="key">密鑰</param>
        /// <param name="MacData">數據</param>
        /// <returns>加密后的Mac驗證碼</returns>
        public static byte[] MAC_CBC(byte[] key,byte[] MacData)
        {
            int count = 0;
            if (MacData.Length % 8 != 0)
            {
                count = 8 - (MacData.Length % 8);

            }

            byte[] tmpData = new byte[count];
            for (int index = 0; index < tmpData.Length; index++)
            {
                tmpData[index] = new byte[] { 0 }[0x30];
            }
            byte[] newMacData = new byte[MacData.Length + tmpData.Length];
            Array.Copy(MacData, 0, newMacData, 0, MacData.Length);
            Array.Copy(tmpData, 0, newMacData, MacData.Length, tmpData.Length);
            
            byte[] bKey=new byte[8];
           
            bKey=key;

            try
            {
                int iGroup = 0;

                byte[] bIV = new byte[] { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };
                byte[] bTmpBuf1 = new byte[8];
                byte[] bTmpBuf2 = new byte[8];

                Array.Copy(bIV, bTmpBuf1, 8);

                if ((newMacData.Length % 8 == 0))
                    iGroup = newMacData.Length / 8;
                else
                    iGroup = newMacData.Length / 8 + 1;

                int i = 0;
                int j = 0;

                for (i = 0; i < iGroup; i++)
                {
                    Array.Copy(newMacData, 8 * i, bTmpBuf2, 0, 8);
                    for (j = 0; j < 8; j++)
                        bTmpBuf1[j] = (byte)(bTmpBuf1[j] ^ bTmpBuf2[j]);
                   
                }
                bTmpBuf2 = HCDES(bKey, bTmpBuf1);
                
                return bTmpBuf2;
            }
            catch
            {
                return new byte[8];
            }
        }

    }
}