import java.io.*;
import java.net.*;

public class KarnTestServer {
   public static void main (String arg[]) {
      BufferedReader in;
      PrintWriter out;
      DiffieHellmanExchange dhe = null;

      // Use Diffie Hellman to create a shared secret
      try {  dhe = new DiffieHellmanExchange("DHKey"); }
      catch (Exception e) {
	 System.out.println("Error getting DHKey from file.");
	 System.exit(1);
      }

      try {
	 // Wait for a connection from a client then connect
	 ServerSocket socket = new ServerSocket(8280);
	 Socket connect = socket.accept();
	 in = new BufferedReader(
                  new InputStreamReader(connect.getInputStream()));
	 out = new PrintWriter (connect.getOutputStream(), true);

	 // Build a Karn encryptor from the shared secret
	 Karn karn = new Karn(dhe.computeSecret(in, out));

	 // Receive encrypted message from client and decrypt
	 String ciphertext = in.readLine();
	 System.out.println("Server: ciphertext:"+ciphertext+"\n");
	 String plaintext = karn.decrypt(ciphertext);
	 System.out.println("Server: plaintext:"+plaintext);

	 // Leave
      } catch (Exception e) {
	 System.out.println("Whoops! - no network");
      }
   }
}