// File: IO12.java (Module 13)
//
// Author: Rahul Simha
// Created: Nov 28, 1998
//
// A chat program using pipes.

import java.awt.*;
import java.awt.event.*;
import java.io.*;

class ChatClient extends Frame implements Runnable {

  OutputStream out_stream;  // The streams.
  InputStream in_stream;
  PrintWriter pw;

  TextField tf;             // For the user to write in.

  Panel message_panel;      // To display the conversation.
  GridLayout grid_layout;
  ScrollPane sc;

  public ChatClient (OutputStream out_stream, InputStream in_stream)
  {
    // Store the stream references and create a PrintWriter
    this.out_stream = out_stream;
    this.in_stream = in_stream;
    pw = new PrintWriter (out_stream, true);
    
    // Create the frame.
    this.setSize (400,200);
    this.setLocation (0,100);
    this.setTitle ("Chat Client");
    this.setBackground (Color.white);
    // this.setLayout (new BorderLayout());

    // This is where messages will be displayed:
    grid_layout = new GridLayout (1,1);
    message_panel = new Panel (grid_layout);
    sc = new ScrollPane ();
    sc.add (message_panel);
    this.add (sc, BorderLayout.CENTER);

    tf = new TextField ();
    tf.setForeground (Color.blue);
    tf.addActionListener (
      new ActionListener () {		       
        public void actionPerformed (ActionEvent a)
	{
	  if (tf.getText().equalsIgnoreCase ("Bye")) {
	    try {
	      pw.println ("Bye");
	      ChatClient.this.out_stream.close ();
	      ChatClient.this.dispose ();
	    }
	    catch (IOException e) { System.out.println (e); }
	  }
	  else {
	    display_text ("ME: " + tf.getText(), Color.blue);
	    pw.println (tf.getText());
	    tf.setText("");
	  }
	}
      }
    );
    this.add (tf, BorderLayout.SOUTH);

    this.setVisible (true);
  }


  // Display text on a message panel using Label's.

  void display_text (String s, Color c)
  {
    // Create the label.
    Label L = new Label (s);
    L.setForeground (c);

    // Add to the message panel.
    message_panel.add (L);
    message_panel.invalidate();

    // Increment the layout rows for the next message.
    grid_layout.setRows (grid_layout.getRows() + 1);

    // Scroll to the bottom.
    int height = sc.getViewportSize().height;
    sc.setScrollPosition (0, height);

    // Re-compute the display.
    this.validate();
  }

  // Must implement the run() method.

  public void run ()
  {
    try {
      // Only reading needs to be done here.
      InputStreamReader isr = new InputStreamReader (in_stream);
      LineNumberReader lnr = new LineNumberReader (isr);
      

      // Read line by line.
      String s = lnr.readLine();
      while (s != null) {
	s = s.trim();
	display_text ("YOU: " + s, Color.red);
	if (s.equalsIgnoreCase ("Bye"))
	  break;
	s = lnr.readLine();
      }
      in_stream.close ();
    }
    catch (IOException e) { System.out.println (e); }

  }

}



// This is an independent quit button to quit the application.

class QuitButton extends Frame {

  public QuitButton ()
  {
    this.setSize (80,50);
    this.setLocation (0, 0);
    this.setTitle ("Quit button");
    Button quitb = new Button ("QUIT");
    quitb.setBackground (Color.red);
    quitb.addActionListener (
      new ActionListener () {
        public void actionPerformed (ActionEvent a)
	{
	  System.exit (0);
	}
      }
    );
    this.add (quitb, BorderLayout.CENTER);
    this.setVisible (true);
  }

}


public class IO12 {

  public static void main (String[] argv)
  {
    // Create an independent quit button.
    QuitButton q = new QuitButton ();

    try {
      // Create the matching pipes. Note that one pipe
      // is given to the constructor of the other.
      PipedOutputStream pipe_out1 = new PipedOutputStream ();
      PipedInputStream pipe_in1 = new PipedInputStream (pipe_out1);

      PipedOutputStream pipe_out2 = new PipedOutputStream ();
      PipedInputStream pipe_in2 = new PipedInputStream (pipe_out2);
      
      // Create one client instance and thread.
      ChatClient c1 = new ChatClient (pipe_out1, pipe_in2);
      Thread c1_thread = new Thread (c1);
      
      // Create another client instance and thread.
      ChatClient c2 = new ChatClient (pipe_out2, pipe_in1);
      Thread c2_thread = new Thread (c2);
      
      // Start the threads.
      c1_thread.start();
      c2_thread.start();
    }
    catch (IOException e) { System.out.println (e); }
  }

}