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

namespace Wms.Screen.Util.Comm
{
    /// <summary>
    /// MD5加密类
    /// </summary>
    public class SecurityUtil
    {
        #region MD5加密
        ///   <summary>
        ///   给一个字符串进行MD5加密
        ///   </summary>
        ///   <param   name="strText">待加密字符串</param>
        ///   <returns>加密后的字符串</returns>
        public static string MD5Encrypt(string strText)
        {
            MD5 md5 = new MD5CryptoServiceProvider();
            byte[] result = md5.ComputeHash(System.Text.Encoding.Default.GetBytes(strText));
            return System.Text.Encoding.Default.GetString(result);
        }

        /// <summary>
        /// MD5加密
        /// </summary>
        /// <param name="str">加密字符</param>
        /// <param name="code">加密位数16/32</param>
        /// <returns></returns>
        public static string MD5(string str, int code)
        {
            MD5CryptoServiceProvider crypto = new MD5CryptoServiceProvider();
            byte[] bytes = Encoding.UTF7.GetBytes(str);
            bytes = crypto.ComputeHash(bytes);
            StringBuilder sb = new StringBuilder();
            foreach (byte num in bytes)
            {
                sb.AppendFormat("{0:x2}", num);
            }
            if (code == 16)
            {
                return sb.ToString().Substring(8, 16);
            }
            else
            {
                return sb.ToString();
            }
        }
        #endregion

        #region  DES加密
        #region ========加密========
        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="Text"></param>
        /// <returns></returns>
        public static string Encrypt(string Text)
        {
            return Encrypt(Text, "BOZHON.COM###");
        }
        /// <summary> 
        /// 加密数据 
        /// </summary> 
        /// <param name="Text"></param> 
        /// <param name="sKey"></param> 
        /// <returns></returns> 
        public static string Encrypt(string Text, string sKey)
        {
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            byte[] inputByteArray;
            inputByteArray = Encoding.Default.GetBytes(Text);
            des.Key = ASCIIEncoding.ASCII.GetBytes(MD5Encrypt(sKey).Substring(0, 8));
            des.IV = ASCIIEncoding.ASCII.GetBytes(MD5Encrypt(sKey).Substring(0, 8));
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);
            cs.Write(inputByteArray, 0, inputByteArray.Length);
            cs.FlushFinalBlock();
            StringBuilder ret = new StringBuilder();
            foreach (byte 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)
        {
            if (!string.IsNullOrEmpty(Text))
            {
                return Decrypt(Text, "BOZHON.COM###");
            }
            else
            {
                return "";
            }
        }
        /// <summary> 
        /// 解密数据 
        /// </summary> 
        /// <param name="Text"></param> 
        /// <param name="sKey"></param> 
        /// <returns></returns> 
        public static string Decrypt(string Text, string sKey)
        {
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            int len;
            len = Text.Length / 2;
            byte[] 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;
            }
            des.Key = ASCIIEncoding.ASCII.GetBytes(MD5Encrypt(sKey).Substring(0, 8));
            des.IV = ASCIIEncoding.ASCII.GetBytes(MD5Encrypt(sKey).Substring(0, 8));
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);
            cs.Write(inputByteArray, 0, inputByteArray.Length);
            cs.FlushFinalBlock();
            return Encoding.Default.GetString(ms.ToArray());
        }

        #endregion
        #endregion

        #region Base64加密
        /// <summary>
        /// Base64加密，采用utf8编码方式加密
        /// </summary>
        /// <param name="source">待加密的明文</param>
        /// <returns>加密后的字符串</returns>
        public static string Base64Encode(string source)
        {
            return Base64Encode(Encoding.UTF8, source);
        }

        /// <summary>
        /// Base64加密
        /// </summary>
        /// <param name="encodeType">加密采用的编码方式</param>
        /// <param name="source">待加密的明文</param>
        /// <returns></returns>
        public static string Base64Encode(Encoding encodeType, string source)
        {
            string encode = string.Empty;
            byte[] bytes = encodeType.GetBytes(source);
            try
            {
                encode = Convert.ToBase64String(bytes);
            }
            catch
            {
                encode = source;
            }
            return encode;
        }

        /// <summary>
        /// Base64解密，采用utf8编码方式解密
        /// </summary>
        /// <param name="result">待解密的密文</param>
        /// <returns>解密后的字符串</returns>
        public static string Base64Decode(string result)
        {
            return Base64Decode(Encoding.UTF8, result);
        }

        /// <summary>
        /// Base64解密
        /// </summary>
        /// <param name="encodeType">解密采用的编码方式，注意和加密时采用的方式一致</param>
        /// <param name="result">待解密的密文</param>
        /// <returns>解密后的字符串</returns>
        public static string Base64Decode(Encoding encodeType, string result)
        {
            string decode = string.Empty;
            byte[] bytes = Convert.FromBase64String(result);
            try
            {
                decode = encodeType.GetString(bytes);
            }
            catch
            {
                decode = result;
            }
            return decode;
        }
    }
    #endregion
}