using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Web.Security;

namespace _1200Gxml心电图绘制
{
    public class DesEncrypt
    {
        #region ========加密========

        /// <summary>
        ///     加密
        /// </summary>
        /// <param name="text"></param>
        /// <returns></returns>
        public static string Encrypt(string text)
        {
            return Encrypt(text, "da1ff5@1b453d1f66d83bc6e7c5cab4$");
        }

        /// <summary>
        ///     加密数据
        /// </summary>
        /// <param name="text"></param>
        /// <param name="sKey"></param>
        /// <returns></returns>
        public static string Encrypt(string text, string sKey)
        {
            var des = new DESCryptoServiceProvider();
            var inputByteArray = Encoding.Default.GetBytes(text);
            var hashPasswordForStoringInConfigFile =
                FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5");
            if (hashPasswordForStoringInConfigFile != null)
                des.Key = Encoding.ASCII.GetBytes(hashPasswordForStoringInConfigFile.Substring(0, 8));
            var passwordForStoringInConfigFile = FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5");
            if (passwordForStoringInConfigFile != null)
                des.IV = Encoding.ASCII.GetBytes(passwordForStoringInConfigFile.Substring(0, 8));
            var ms = new MemoryStream();
            var cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
            cs.Write(inputByteArray, 0, inputByteArray.Length);
            cs.FlushFinalBlock();
            var ret = new StringBuilder();
            foreach (var b in ms.ToArray()) ret.AppendFormat("{0:X2}", b);
            return ret.ToString();
        }

        #endregion

        #region ========解密========

        /// <summary>
        ///     解密
        /// </summary>
        /// <param name="text"></param>
        /// <returns></returns>
        public static string Decrypt(string text)
        {
            return Decrypt(text, "da1ff5@1b453d1f66d83bc6e7c5cab4$");
        }

        /// <summary>
        ///     解密数据
        /// </summary>
        /// <param name="text"></param>
        /// <param name="sKey"></param>
        /// <returns></returns>
        public static string Decrypt(string text, string sKey)
        {
            var des = new DESCryptoServiceProvider();
            var len = text.Length / 2;
            var inputByteArray = new byte[len];
            int x, i;
            for (x = 0; x < len; x++)
            {
                i = Convert.ToInt32(text.Substring(x * 2, 2), 16);
                inputByteArray[x] = (byte)i;
            }

            var hashPasswordForStoringInConfigFile =
                FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5");
            if (hashPasswordForStoringInConfigFile != null)
                des.Key = Encoding.ASCII.GetBytes(hashPasswordForStoringInConfigFile.Substring(0, 8));
            var passwordForStoringInConfigFile = FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5");
            if (passwordForStoringInConfigFile != null)
                des.IV = Encoding.ASCII.GetBytes(passwordForStoringInConfigFile.Substring(0, 8));
            var ms = new MemoryStream();
            var cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
            cs.Write(inputByteArray, 0, inputByteArray.Length);
            cs.FlushFinalBlock();
            return Encoding.Default.GetString(ms.ToArray());
        }

        #endregion
    }
}