import java.io.*;
import java.net.Socket;
import java.util.Date;

public class Monitor
{
  public static void main(String[] args)
  {
    try {
      new Monitor();
    } catch (Exception e) {
      fatal(e);
    }
  }

  private static synchronized void fatal(Throwable e)
  {
    try {
      PrintWriter out =
        new PrintWriter(new FileWriter("Monitor.dump", /*append=*/ true));
      try {
        out.write("Exception in ");
        out.write(Thread.currentThread().getName());
        out.write(" thread at ");
        out.write(new Date().toString());
        out.write("\r\n");
        e.printStackTrace(out);
      } finally {
        out.close();
      }
    } catch (IOException f) {
    }
    System.exit(1);
  }

  private Process fProc;
  private Socket fRemote;
  private InputStream fRemoteIn;
  private OutputStream fRemoteOut;
  private int fThreadCount;

  Monitor() throws IOException
  {
    fRemote = new Socket("localhost", Server.PORT);
    fRemoteIn = fRemote.getInputStream();
    fRemoteOut = fRemote.getOutputStream();

    fProc = Runtime.getRuntime().exec("GNUChess");
    fThreadCount = 2;
    new WatchThread(System.in, fProc.getOutputStream(), true);
    new WatchThread(fProc.getInputStream(), System.out, false);
  }

  synchronized void send(byte[] buffer, int length) throws IOException
  {
    fRemoteOut.write(buffer, 0, length);
    fRemoteOut.flush();
    fRemoteIn.read();
  }

  synchronized void threadDone()
  {
    fThreadCount--;
    if (fThreadCount == 0) {
      try {
        fRemote.close();
      } catch (IOException e) {
      }
    }
  }

  class WatchThread extends Thread
  {
    private InputStream fIn;
    private OutputStream fOut;
    private byte[] fBuffer = new byte[128];
    private int fLength = 0;
    private String fLine;

    protected WatchThread(InputStream in, OutputStream out, boolean toEngine)
    {
      super(toEngine ? "ToEngine" : "FromEngine");
      fIn = in;
      fOut = out;
      fBuffer[0] = (byte) (toEngine ? '>' : '<');
      fLength = 1;
      start();
    }

    public void run()
    {
      try {
        while(true) {
          int ch = fIn.read();
          if (ch == -1)
            break;
          if (ch == '\r')
            continue;
          fBuffer[fLength++] = (byte) ch;
          if (ch == '\n') {
            send(fBuffer, fLength);

            fOut.write(fBuffer, 1, fLength-1);
            fOut.flush();
            fLength = 1;
          }
        }
        threadDone();
      } catch(Exception e) {
        fatal(e);
      }
    }
  }
}