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

namespace AllBase
{
    public class BaseEncrypt
    {
        #region EBFB8THEA 加密
        public static string _KEY = "XNNRSAA1";  //密钥
        public static string _IV = "RSABPDD2";   //向量

        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="data">需要加密的文本</param>
        /// <returns></returns>
        public static string EncryptEncode(string data, string _key = "", string _iv = "")
        {
            if (string.IsNullOrEmpty(_key))
                _key = _KEY;
            if (string.IsNullOrEmpty(_iv))
                _iv = _IV;

            byte[] byKey = System.Text.ASCIIEncoding.ASCII.GetBytes(_key);
            byte[] byIV = System.Text.ASCIIEncoding.ASCII.GetBytes(_iv);

            DESCryptoServiceProvider cryptoProvider = new DESCryptoServiceProvider();
            int i = cryptoProvider.KeySize;
            MemoryStream ms = new MemoryStream();
            CryptoStream cst = new CryptoStream(ms, cryptoProvider.CreateEncryptor(byKey, byIV), CryptoStreamMode.Write);

            StreamWriter sw = new StreamWriter(cst);
            sw.Write(data);
            sw.Flush();
            cst.FlushFinalBlock();
            sw.Flush();
            string strRet = Convert.ToBase64String(ms.GetBuffer(), 0, (int)ms.Length);

            sw.Dispose();
            sw.Close();
            cst.Dispose();
            cst.Close();
            ms.Dispose();
            ms.Close();
            return strRet;
        }

        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="data"></param>
        /// <returns></returns>
        public static string EncryptDecode(string data, string _key = "", string _iv = "")
        {
            try
            {
                if (string.IsNullOrEmpty(_key))
                    _key = _KEY;
                if (string.IsNullOrEmpty(_iv))
                    _iv = _IV;

                byte[] byKey = System.Text.ASCIIEncoding.ASCII.GetBytes(_key);
                byte[] byIV = System.Text.ASCIIEncoding.ASCII.GetBytes(_iv);
                byte[] byEnc;

                try
                {
                    data.Replace("_%_", "/");
                    data.Replace("-%-", "#");
                    byEnc = Convert.FromBase64String(data);
                }
                catch
                {
                    return "";
                }

                DESCryptoServiceProvider cryptoProvider = new DESCryptoServiceProvider();
                MemoryStream ms = new MemoryStream(byEnc);
                CryptoStream cst = new CryptoStream(ms, cryptoProvider.CreateDecryptor(byKey, byIV), CryptoStreamMode.Read);
                StreamReader sr = new StreamReader(cst);
                var result = sr.ReadToEnd();

                sr.Dispose();
                sr.Close();
                cst.Dispose();
                cst.Close();
                ms.Dispose();
                ms.Close();

                return result;
            }
            catch (Exception ex)
            {
                return "";
            }
        }
        #endregion

        #region 数字签名校验
        public static string sPrivateKey = "<RSAKeyValue><Modulus>oOS7iOYBmFdhSPYmae8Vav6DNvzFqEp08UWzNr6Jq3WetYNrVriB7EGcmSWpK4b+vu+NPhFuXRt4WMo06kJLll7kDeVBYJooXCQQaNQT1Gv4l2zcWgutCBtzIAs8YGwUgjkFdnIN8bIGOdGbQAaxIJpnifCzX5Iw2qd2YaBQMjM=</Modulus><Exponent>AQAB</Exponent><P>3w7I1TzMMt7d9fYkQINQamyqVT+Ke/WU8Z+RMFpfiYmzu+EorIxeRe5yEG1TMYD2uHPX7K8K9IwxoTF2SxcXmQ==</P><Q>uKevEc6B4LTwebVcE8UYk4ZjRW2ADDe223ajc9yZKguboXTrv1euPEnEoWibKANZ7a6ktW+ok7M30T7+6hhHqw==</Q><DP>a0JWvIMhxgx5Oz8DK6p5TtO2DIwjcXwkBRQv4spySlbXAK9CucY9xu7kFpYbfSCAgy3hVMTPRczsSJDaSz1tcQ==</DP><DQ>Oc1r1RQivdeGC2NFLn8dIVkJDDupwKlUGUD7C5K7c1js38682Um2JfMllS0snIroBKoNryoDyDBqwZqJq3fsPw==</DQ><InverseQ>nOsce/v2jCJKY1/SeOsLiwa7n5fLIKEdIBBeLURLYuELI/9RyElBM5KwNUCXWylCkVc5DRGyoExOWzZgdUk5Kw==</InverseQ><D>H2lov6qAJzjwEmmUSFxYJyJ3hbXF9TxMJorAGXELucDl8nQs8apmGzUYGMJEi+34MFjej36huGXTkiowOIgm724PlVgjQGyr9hqBFO9WTKwXQrgZaoG235HBDGh5oq1fkBNZ415msYsqwmtif7a6qAL9tEJiPlBWpg5/EJA9wVE=</D></RSAKeyValue>";
        public static string sPublicKey = "<RSAKeyValue><Modulus>oOS7iOYBmFdhSPYmae8Vav6DNvzFqEp08UWzNr6Jq3WetYNrVriB7EGcmSWpK4b+vu+NPhFuXRt4WMo06kJLll7kDeVBYJooXCQQaNQT1Gv4l2zcWgutCBtzIAs8YGwUgjkFdnIN8bIGOdGbQAaxIJpnifCzX5Iw2qd2YaBQMjM=</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>";

        /// <summary>
        /// 数字签名
        /// </summary>
        /// <param name="plaintext">原文</param>
        /// <param name="privateKey">私钥</param>
        /// <returns>签名</returns>
        public static string DataSign(string plaintext, string privateKey = "")
        {
            if (string.IsNullOrEmpty(privateKey))
                privateKey = sPrivateKey;

            UnicodeEncoding ByteConverter = new UnicodeEncoding();
            byte[] dataToEncrypt = ByteConverter.GetBytes(plaintext);

            using (RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider())
            {
                RSAalg.FromXmlString(privateKey);
                //使用SHA1进行摘要算法，生成签名
                byte[] encryptedData = RSAalg.SignData(dataToEncrypt, new SHA1CryptoServiceProvider());
                return Convert.ToBase64String(encryptedData);
            }
        }

        /// <summary>
        /// 验证签名
        /// </summary>
        /// <param name="plaintext">原文</param>
        /// <param name="signedData">签名</param>
        /// <param name="publicKey">公钥</param>
        /// <returns></returns>
        public static bool DataVerify(string plaintext, string signedData, string publicKey = "")
        {
            if (string.IsNullOrEmpty(publicKey))
                publicKey = sPublicKey;

            using (RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider())
            {
                RSAalg.FromXmlString(publicKey);
                UnicodeEncoding ByteConverter = new UnicodeEncoding();
                byte[] dataToVerifyBytes = ByteConverter.GetBytes(plaintext);
                byte[] signedDataBytes = Convert.FromBase64String(signedData);
                return RSAalg.VerifyData(dataToVerifyBytes, new SHA1CryptoServiceProvider(), signedDataBytes);
            }
        }
        #endregion

        /// <summary>
        /// 获取非对程加密Key
        /// 键为公钥，值为私钥
        /// </summary>
        /// <returns></returns>
        public static KeyValuePair<string, string> CreateRSAKey()
        {
            RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
            string privateKey = RSA.ToXmlString(true);
            string publicKey = RSA.ToXmlString(false);

            return new KeyValuePair<string, string>(publicKey, privateKey);
        }

        private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
        /// <summary>
        /// 进行DES解密。
        /// </summary>
        /// <param name="pToDecrypt">要解密的base64串</param>
        /// <param name="sKey">密钥，且必须为8位。</param>
        /// <returns>已解密的字符串。</returns>
        public static string DESDecode(string source, string sKey)
        {
            //try
            //{
            //    byte[] rgbKey = Encoding.UTF8.GetBytes(sKey);
            //    byte[] rgbIV = Keys;
            //    byte[] inputByteArray = Convert.FromBase64String(source);
            //    DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
            //    MemoryStream mStream = new MemoryStream();
            //    CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
            //    cStream.Write(inputByteArray, 0, inputByteArray.Length);
            //    cStream.FlushFinalBlock();
            //    return Encoding.UTF8.GetString(mStream.ToArray());
            //}
            //catch
            //{
            //    return source;
            //}


            try
            {
                byte[] inputByteArray = System.Convert.FromBase64String(source);//Encoding.UTF8.GetBytes(source);
                using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
                {
                    des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
                    des.IV = Keys;
                    System.IO.MemoryStream ms = new System.IO.MemoryStream();
                    using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write))
                    {
                        cs.Write(inputByteArray, 0, inputByteArray.Length);
                        cs.FlushFinalBlock();
                        cs.Close();
                    }
                    string str = Encoding.UTF8.GetString(ms.ToArray());
                    ms.Close();
                    return str;
                }
            }
            catch (Exception ex)
            {
                return "";
            }
        }

        /// <summary>
        /// DES加密方法
        /// </summary>
        /// <param name="encryptedValue">要加密的字符串</param>
        /// <param name="key">密钥</param>
        /// <returns>加密后的字符串</returns>
        public static string DESEncrypt(string originalValue, string key)
        {
            try
            {
                using (DESCryptoServiceProvider sa = new DESCryptoServiceProvider { Key = Encoding.UTF8.GetBytes(key), IV = Keys })
                {
                    using (ICryptoTransform ct = sa.CreateEncryptor())
                    {
                        byte[] by = Encoding.UTF8.GetBytes(originalValue);
                        using (var ms = new MemoryStream())
                        {
                            using (var cs = new CryptoStream(ms, ct, CryptoStreamMode.Write))
                            {
                                cs.Write(by, 0, by.Length);
                                cs.FlushFinalBlock();
                            }
                            return Convert.ToBase64String(ms.ToArray());
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                LogSave.Add("DES Encrypt Exception:" + ex.Message);
                return "";
            }
        }
    }
}