import java.net.*;
import java.io.*;
import java.security.*;
import java.security.spec.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import javax.swing.*;

//import skip.java;

public class Client
{
	Socket s;
	InputStream in;
	OutputStream out;

	Client()
	{	}

	public void Communication ()
	{

		try
		{





			  String host = "127.0.0.1";
			    //int port = Integer.parseInt( args[1] );
			    int port = 4444;
//			    String outfile = args[2];

			    // Create a Diffie-Hellman key pair (public and private).
			    KeyPairGenerator kpg = KeyPairGenerator.getInstance( "DH" );
			    kpg.initialize(Skip.sDHParameterSpec);
			    KeyPair LukekeyPair = kpg.genKeyPair();

			    // Create socket and contact host.
			    Socket s = new Socket( host, port ); // Wait to be recognized.

			    DataInputStream myin = new DataInputStream( s.getInputStream() );
			    DataOutputStream myout = new DataOutputStream( s.getOutputStream() );

			    // Send our public key to host.
			    byte[ ] keyBytes = LukekeyPair.getPublic().getEncoded();
			    myout.writeInt( keyBytes.length );
			    myout.write( keyBytes );

			    // Accept public key from host (length, key in bytes).
			    keyBytes = new byte[ myin.readInt( ) ];
			    myin.readFully( keyBytes );
			    KeyFactory kf = KeyFactory.getInstance( "DH" );
			    X509EncodedKeySpec x509Spec = new X509EncodedKeySpec( keyBytes );
			    PublicKey HanPublicKey = kf.generatePublic(x509Spec);

			    // Generate the secret session key.
			    KeyAgreement ka = KeyAgreement.getInstance( "DH" );
			    ka.init( LukekeyPair.getPrivate() );
			    ka.doPhase( HanPublicKey, true );
			    byte[] secret = ka.generateSecret();

			   //  in c:\jdk1.2.2\jre\classes\edu.shsu.util.BASE64
			   // System.out.println( edu.shsu.util.BASE64.encode(secret) );

//	     FileOutputStream fout = new FileOutputStream(outfile);

			      // First create a key specification from the password, then the key.
			      //byte[] desKeyData = password.getBytes();
			      DESKeySpec desKeySpec = new DESKeySpec(secret);
			      SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
			      SecretKey desKey = keyFactory.generateSecret(desKeySpec);

System.out.println( BASE64.encode(secret) );









			// establish conection
			//s = new Socket("127.0.0.1", 4444);

			//initiate I/O stream
			in = s.getInputStream();
			out = s.getOutputStream();

			//communication...
			SendMessage("Connection established... Thank you.");
			GetMessage();
			SendMessage("Good Morning This is a Test from Client\n");
			GetMessage();
			SendMessage("Thank you...");
			GetMessage();

			//close connection
			out.close();
			in.close();
			s.close();
		}
		catch (Exception e) { }
	}

	public static void main(String arg[])
	{
		Client client = new Client();
		client.Communication();
	}

	public void SendMessage(String msg)
	{
		try
		{
			byte b[] = new byte [100];
			b = msg.getBytes();
			out.write(b);
			out.flush();
		}
		catch(Exception e) {}
	}

//	public void SendMessage(int msg)
///	{
///		try
///		{
//			out.write(msg);
//			out.flush();
//		}
//		catch(Exception e) {}
//	}

	public void GetMessage()
	//void GetMessage()
{
try
	{
//String outfile = "Out1.txt";
FileOutputStream fout = new FileOutputStream(outfile);

      // Read the initialization vector.
      int ivSize = myin.readInt();
      byte[] iv = new byte[ivSize];
      myin.readFully(iv);
      IvParameterSpec ivps = new IvParameterSpec(iv);

      // use Data Encryption Standard
      Cipher des = Cipher.getInstance("DES/CBC/PKCS5Padding");
      des.init(Cipher.DECRYPT_MODE, desKey, ivps);

      // Accept the encryped transmission, decrypt, and save in file.
      byte[] input = new byte[64];
      while (true)
      {
        int bytesRead = myin.read(input);
        if (bytesRead == -1) break;
        byte[] output = des.update(input, 0, bytesRead);
        if (output != null)
        {
		//	fout.write(output);
           System.out.print("Server --> " + new String(output) );
	    }
      }

      byte[] output = des.doFinal();
      if (output != null)
      {
		 // fout.write(output);
      System.out.print("Server --> " + new String(output) ); }

//      fout.flush();
//      fout.close();
    myout.close();
    myin.close();

   }




//		{			byte b[] = new byte[100];
//			in.read(b);
//			System.out.println("Server --> "+ new String(b));
//		}
		catch(Exception e){}
//	}

//    fout.flush();
//    fout.close();
//   myout.close();
//   myin.close();

  }
}