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

namespace HH.WMS.Utils
{
    public class Symmetric
    {
        private SymmetricAlgorithm mobjCryptoService;
        private string Key;
        /// <summary>   
        /// ¶Ô³Æ¼ÓÃÜÀàµÄ¹¹Ô캯Êý   
        /// </summary>   
        public Symmetric()
        {
            mobjCryptoService = new RijndaelManaged();
            Key = "Guz(%&hj7x89H$yuBI0456FtmaT5&fvHUFCy76*h%(HilJ$lhj!y6&(*jkP87jH7";
        }
        /// <summary>   
        /// »ñµÃÃÜÔ¿   
        /// </summary>   
        /// <returns>ÃÜÔ¿</returns>   
        private byte[] GetLegalKey()
        {
            string sTemp = Key;
            mobjCryptoService.GenerateKey();
            byte[] bytTemp = mobjCryptoService.Key;
            int KeyLength = bytTemp.Length;
            if (sTemp.Length > KeyLength)
                sTemp = sTemp.Substring(0, KeyLength);
            else if (sTemp.Length < KeyLength)
                sTemp = sTemp.PadRight(KeyLength, ' ');
            return ASCIIEncoding.ASCII.GetBytes(sTemp);
        }
        /// <summary>   
        /// »ñµÃ³õʼÏòÁ¿IV   
        /// </summary>   
        /// <returns>³õÊÔÏòÁ¿IV</returns>   
        private byte[] GetLegalIV()
        {
            string sTemp = "E4ghj*Ghg7!rNIfb&95GUY86GfghUb#er57HBh(u%g6HJ($jhWk7&!hg4ui%$hjk";
            mobjCryptoService.GenerateIV();
            byte[] bytTemp = mobjCryptoService.IV;
            int IVLength = bytTemp.Length;
            if (sTemp.Length > IVLength)
                sTemp = sTemp.Substring(0, IVLength);
            else if (sTemp.Length < IVLength)
                sTemp = sTemp.PadRight(IVLength, ' ');
            return ASCIIEncoding.ASCII.GetBytes(sTemp);
        }
        /// <summary>   
        /// ¼ÓÃÜ·½·¨   
        /// </summary>   
        /// <param name="Source">´ý¼ÓÃܵĴ®</param>   
        /// <returns>¾­¹ý¼ÓÃܵĴ®</returns>   
        public string Encrypto(string Source)
        {
            byte[] bytIn = UTF8Encoding.UTF8.GetBytes(Source);
            MemoryStream ms = new MemoryStream();
            mobjCryptoService.Key = GetLegalKey();
            mobjCryptoService.IV = GetLegalIV();
            ICryptoTransform encrypto = mobjCryptoService.CreateEncryptor();
            CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);
            cs.Write(bytIn, 0, bytIn.Length);
            cs.FlushFinalBlock();
            ms.Close();
            byte[] bytOut = ms.ToArray();
            return Convert.ToBase64String(bytOut);
        }
        /// <summary>   
        /// ½âÃÜ·½·¨   
        /// </summary>   
        /// <param name="Source">´ý½âÃܵĴ®</param>   
        /// <returns>¾­¹ý½âÃܵĴ®</returns>   
        public string Decrypto(string Source)
        {
            byte[] bytIn = Convert.FromBase64String(Source);
            MemoryStream ms = new MemoryStream(bytIn, 0, bytIn.Length);
            mobjCryptoService.Key = GetLegalKey();
            mobjCryptoService.IV = GetLegalIV();
            ICryptoTransform encrypto = mobjCryptoService.CreateDecryptor();
            CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Read);
            StreamReader sr = new StreamReader(cs);
            return sr.ReadToEnd();
        }



    }
}