using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;

namespace COMMON.DEncrypt
{
    public class TDESCSPEncrypt
    {
        //12个字符  
        private static string customIV = "jfYi3ggEEV4=";//"4vHKRj3yfzU=";
        //32个字符  
        private static string customKey = "9DQrNW0KBi1LLGok6ayQtvuZucoXtLb0";//"xhVs6DRXLfUGxw+AhtfQdpQGoa+8SA9d";

        /// <summary>  
        /// 加密字符串  
        /// </summary>  
        /// <param name="password"></param>  
        /// <returns></returns>  
        public static string EncryptPassword(string password, string key_Base64, string iv_Base64)
        {
            string encryptPassword = string.Empty;

            SymmetricAlgorithm algorithm = new TripleDESCryptoServiceProvider();
            algorithm.Key = Convert.FromBase64String(key_Base64);
            algorithm.IV = Convert.FromBase64String(iv_Base64);
            algorithm.Mode = CipherMode.ECB;
            algorithm.Padding = PaddingMode.PKCS7;

            ICryptoTransform transform = algorithm.CreateEncryptor();

            byte[] data = Encoding.Unicode.GetBytes(password);
            MemoryStream memoryStream = new MemoryStream();
            CryptoStream cryptoStream = new CryptoStream(memoryStream, transform, CryptoStreamMode.Write);

            cryptoStream.Write(data, 0, data.Length);
            cryptoStream.FlushFinalBlock();
            encryptPassword = Convert.ToBase64String(memoryStream.ToArray());

            memoryStream.Close();
            cryptoStream.Close();

            return encryptPassword;
        }

        /// <summary>  
        /// 解密字符串  
        /// </summary>  
        /// <param name="encryptPassword"></param>  
        /// <returns></returns>  
        public static string DecryptPassword(string encryptPassword, string key_Base64, string iv_Base64)
        {
            string decryptPassword = string.Empty;

            SymmetricAlgorithm algorithm = new TripleDESCryptoServiceProvider();
            algorithm.Key = Convert.FromBase64String(key_Base64);
            algorithm.IV = Convert.FromBase64String(iv_Base64);
            algorithm.Mode = CipherMode.ECB;
            algorithm.Padding = PaddingMode.PKCS7;

            ICryptoTransform transform = algorithm.CreateDecryptor(algorithm.Key, algorithm.IV);

            byte[] buffer = Convert.FromBase64String(encryptPassword);
            MemoryStream memoryStream = new MemoryStream(buffer);
            CryptoStream cryptoStream = new CryptoStream(memoryStream, transform, CryptoStreamMode.Read);
            StreamReader reader = new StreamReader(cryptoStream, Encoding.Unicode);
            decryptPassword = reader.ReadToEnd();

            reader.Close();
            cryptoStream.Close();
            memoryStream.Close();

            return decryptPassword;
        }

        public static string EncryptPassword(string password, string key_Base64)
        {
            return EncryptPassword(password, key_Base64, customIV);
        }

        public static string DecryptPassword(string encryptPassword, string key_Base64)
        {
            return DecryptPassword(encryptPassword, key_Base64, customIV);
        }

        public static string EncryptPassword(string password)
        {
            return EncryptPassword(password, customKey, customIV);
        }

        public static string DecryptPassword(string encryptPassword)
        {
            return DecryptPassword(encryptPassword, customKey, customIV);
        }

        static TripleDESCryptoServiceProvider _DCSP;
        private static TripleDESCryptoServiceProvider DCSP
        {
            get
            {
                if (_DCSP == null)
                    _DCSP = new TripleDESCryptoServiceProvider();
                //
                return _DCSP;
            }
        }

        public static string CreateKEY()
        {
            DCSP.GenerateKey();
            return Convert.ToBase64String(DCSP.Key);
        }
    }
}