// File: IO6.java (Module 13)
//
// Author: Rahul Simha
// Created: Nov 18, 1998
//
// Concurrent Producer-Consumer with pipes and a buffer
// with a half-way flush.

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


class Producer extends Frame implements Runnable {

  Label L;     // A place to write stuff.
  OutputStream out_stream;

  public Producer (OutputStream out_stream)
  {
    // Store the reference to the output stream.
    this.out_stream = out_stream;

    // Create the frame.
    this.setSize (600,100);
    this.setLocation (0,100);
    this.setTitle ("Producer");
    this.setBackground (Color.white);
    // this.setLayout (new BorderLayout());

    // This is where we will write to.
    L = new Label ("");
    this.add (L, BorderLayout.CENTER);

    this.setVisible (true);
  }


  // Must implement the run() method.

  public void run ()
  {
    // Write 25 random bytes to the buffer.

    for (int i=1; i<=25; i++) {
      // Create a random byte
      byte k = (byte) UniformRandom.uniform (1, 100);

      // Write to label first.
      L.setText (L.getText() + " " + k);

      // Write it to the screen.
      System.out.println ("Producer: writing " + k);

      // Write integer to buffer.
      try {
	out_stream.write (k);
	if (i == 12) out_stream.flush ();
      }
      catch (IOException e) { System.out.println (e); }

      // Sleep for a while.
      try {
	Thread.sleep ((int)UniformRandom.uniform(100,1000));
      } catch (InterruptedException e) { System.out.println (e); }
    }

    // Write EOF and close output stream.
    try {
      out_stream.write (-1);
      out_stream.close ();
    }
    catch (IOException e) { System.out.println (e); }

    L.setText (L.getText() + " Done!");
  }

}


class Consumer extends Frame implements Runnable {

  Label L;     // Data similar to Producer.
  InputStream in_stream;

  public Consumer (InputStream in_stream)
  {
    this.in_stream = in_stream;

    this.setSize (600,100);
    this.setLocation (0, 200);
    this.setTitle ("Consumer");
    this.setBackground (Color.white);
    // this.setLayout (new BorderLayout());

    L = new Label ("");
    this.add (L, BorderLayout.CENTER);

    this.setVisible (true);
  }


  public void run ()
  {
    // Read byte values until EOF.

    while (true) {
      // Get the next byte
      int i = -1;
      try {
	i = in_stream.read ();
      }
      catch (IOException e) { System.out.println (e); }

      // Extract byte.
      byte k = (byte) i;

      // Check if end-of-data.
      if ( (i < 0) || (k < 0) ) break;

      System.out.println ("Consumer: just read " + k);

      // Write it on the frame.
      L.setText (L.getText() + " " + k);

      // Sleep for a while.
      try {
	Thread.sleep ((int)UniformRandom.uniform(5,10));
      }
      catch (InterruptedException e) { System.out.println (e); }
    }

    L.setText (L.getText() + " Done!");
    try {
      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 IO6 {

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

    try {
      // Create the matching pipes.
      PipedOutputStream pipe_out = new PipedOutputStream ();
      PipedInputStream pipe_in = new PipedInputStream (pipe_out);
      
      // Wrap a buffer around the Producer.
      BufferedOutputStream buf_out = new BufferedOutputStream (pipe_out);

      // Create a producer instance and thread. Pass the buffer in.
      Producer p = new Producer (buf_out);
      Thread pthread = new Thread (p);
      
      // Create a consumer instance and thread.
      Consumer c = new Consumer (pipe_in);
      Thread cthread = new Thread (c);
      
      // Start the threads.
      pthread.start();
      // At this time, all the data is sitting in the buffer.
      // Flush it out.
      buf_out.flush();

      cthread.start();
    }
    catch (IOException e) { System.out.println (e); }
  }

}