using System;
using System.IO;
using com.hitrust.Security.Certificates;
using System.Security.Cryptography;
using System.Security.Cryptography.X509Certificates;
using Bwp.ABCClient2.Core;
using System.Text;
using System.IO.Compression;
namespace com.hitrust.trustpay.client
{
  /// <summary>
  /// 用来替换原来的配置，以适应我们的程序的需要
  /// </summary>
  public class MerchantConfig
  {
    public static Encoding DefaultEncoding = Encoding.GetEncoding("GB18030");

    public MerchantConfig()
    {
    }

    static ABCClientConfig Config
    {
      get
      {
        return new ABCClientConfig();
      }
    }

    public static BufferedStream getTrxLogFile()
    {
      BufferedStream tLogFile = null;
      if (Config.EnableLog)
      {
        string tFileName = "";
        try
        {
          HiCalendar tHiCalendar = new HiCalendar();
          tFileName = Config.LogPath + "/TrxLog." + tHiCalendar.toString("%Y%m%d.log");
          tLogFile = new BufferedStream(new FileStream(tFileName, FileMode.Append));
        }
        catch (IOException)
        {
          throw new TrxException("1004", "无法写入交易日志文档", " - 系统无法写入交易日志至[" + tFileName + "]中!");
        }
      }
      return tLogFile;
    }

    /// <summary>
    /// 这里程序传入的aMerchantNo不起作用
    /// 通过外部环境来知道所选择的商户
    /// </summary>
    /// <param name="aMerchantNo"></param>
    /// <returns></returns>
    public static string MerchantID(int aMerchantNo)
    {
      return Config.MerchanID;
    }

    /// <summary>
    /// 得到商户的私钥
    /// </summary>
    /// <param name="aMerchantNo"></param>
    /// <returns></returns>
    public static RSACryptoServiceProvider MerchantKey(int aMerchantNo)
    {
      return Config.MerchanPrivateKey;
    }

    public static XMLDocument signMessage(int aMerchantNo, XMLDocument aMessage)
    {
      var tMerchantKey = MerchantKey(aMerchantNo);
      if (tMerchantKey == null)
      {
        throw new Exception("未能找到私钥");
      }
      byte[] tHashedData = new SHA1Managed().ComputeHash(DefaultEncoding.GetBytes(aMessage.ToString()));
      byte[] tSigned = tMerchantKey.SignHash(tHashedData, CryptoConfig.MapNameToOID("SHA1"));
      string tSignedBase64 = Convert.ToBase64String(tSigned);
      return new XMLDocument(aMessage.ToString() + "<Signature-Algorithm>SHA1withRSA</Signature-Algorithm><Signature>" + tSignedBase64 + "</Signature>");
    }

    public static XMLDocument verifySign(XMLDocument aMessage)
    {
      return verifySign(aMessage, true);
    }

    public static XMLDocument verifySign(XMLDocument aMessage, bool needMessageHeader)
    {
      XMLDocument tTrxResponse = aMessage.getValue("Message");
      if (tTrxResponse == null)
      {
        throw new TrxException("1301", "网上支付平台的响应报文不完整", "无[Message]段！");
      }
      if (aMessage.getValueNoNull("Signature-Algorithm") == null)
      {
        throw new TrxException("1301", "网上支付平台的响应报文不完整", "无[Signature-Algorithm]段！");
      }
      string tSignBase64 = aMessage.getValueNoNull("Signature");
      if (tSignBase64 == null)
      {
        throw new TrxException("1301", "网上支付平台的响应报文不完整", "无[Signature]段！");
      }
      byte[] tSign = Convert.FromBase64String(tSignBase64);
      try
      {
        SHA1Managed tHash = new SHA1Managed();
        var message = "";
        if (needMessageHeader)
          message = "<Message>" + tTrxResponse.ToString() + "</Message>";
        else
          message = tTrxResponse.ToString();
        byte[] tHashedData = tHash.ComputeHash(DefaultEncoding.GetBytes(message));


        var publicKey = (RSACryptoServiceProvider)TrustpayCertificate.PublicKey.Key;

        bool tResult = publicKey.VerifyHash(tHashedData, Const.SHA1OID, tSign);
        tHash.Clear();
        publicKey.Clear();
        if (!tResult)
        {
          throw new TrxException("1302", "网上支付平台的响应报文签名验证失败");
        }
      }
      catch (TrxException e)
      {
        throw e;
      }
      catch (Exception e)
      {
        Console.Out.WriteLine(e);
        throw new TrxException("1302", "网上支付平台的响应报文签名验证失败 - " + e.ToString());
      }
      return tTrxResponse;
    }

    public static int MerchantNum
    {
      get
      {
        return 1;
      }
    }

    public static X509Certificate2 TrustpayCertificate
    {
      get
      {
        return (X509Certificate2)Config.ABCPublicKey;
      }
    }

    public static string TrustPayConnectMethod
    {
      get
      {
        return Config.TrustPayConnectMethod;
      }
    }

    public static string TrustPayNewLine
    {
      get
      {
        return "\r\n";
      }
    }

    public static string TrustPayServerName
    {
      get
      {
        return Config.TrustPayServerName;
      }
    }

    public static int TrustPayServerPort
    {
      get
      {
        return Config.TrustPayServerPort;
      }
    }

    public static string TrustPayTrxURL
    {
      get
      {
        return Config.TrustPayTrxURL;
      }
    }

    internal static string DeCompress(string comppressedString)
    {
      byte[] byteInput = Convert.FromBase64String(comppressedString);
      using (var srcStream = new MemoryStream(byteInput))
      {
        using (var destStream = new MemoryStream())
        {
          using (GZipStream decompress = new GZipStream(srcStream, CompressionMode.Decompress))
          {
            decompress.CopyTo(destStream);
            var resultBytes = destStream.ToArray();
            return CompressEncoding.GetString(resultBytes, 0, resultBytes.Length);
          }
        }
      }
    }

    static Encoding CompressEncoding = Encoding.GetEncoding("GB18030");

    internal static string Compress(string uncompressedString)
    {
      byte[] byteData = CompressEncoding.GetBytes(uncompressedString);
      using (MemoryStream srcStream = new MemoryStream(byteData))
      {
        using (var destStream = new MemoryStream())
        {
          using (GZipStream compress = new GZipStream(destStream, CompressionMode.Compress))
          {
            srcStream.CopyTo(compress);
          }
          return Convert.ToBase64String(destStream.ToArray());
        }
      }
    }
  }
}