/*
 * cs101 Graphical Console 
 *
 * Developed for "Rethinking CS101", a project of Lynn Andrea Stein's AP Group.
 * For more information, see <a href="http://www.ai.mit.edu/projects/cs101/">the
 * CS101 homepage</a> or email <las@ai.mit.edu>.
 *
 * Copyright (C) 1998 Massachusetts Institute of Technology.
 * Please do not redistribute without obtaining permission.
 */

package cs101.awt;

import java.awt.*;
import java.awt.event.*;
import cs101.util.queue.Queue;
import cs101.util.queue.DefaultQueue;
import cs101.util.queue.EmptyQueueException;

/**
 * A graphical helper class for Java Console IO.  Contains appropiate
 * console read and print methods.<p>
 *
 * Exists mostly to ease the differences between the numerous (and
 * sometimes broken) IDE java consoles.<p>
 *
 * Copyright (c) 1998 Massachusetts Institute of Technolgoy
 *
 * @author   Todd C. Parnell, tparnell@ai.mit.edu
 * @version  $Id: Console.java,v 1.1.1.1 2002/06/05 21:56:32 root Exp $
 *
 * @see cs101.io.Console 
 */
public class Console extends Frame {

  /** Buffer for input lines not yet read. */
  private Queue inputLines;
  
  private TextArea ta;
  
  /**
   * Create and display a new Console.
   */
  public Console() {
    super("CS101 Console");
    
    this.inputLines = new DefaultQueue();
    
    this.ta = new TextArea("", 24, 80, TextArea.SCROLLBARS_BOTH);
    ta.setFont(new Font("Monospaced", Font.PLAIN, 10));
    ta.addKeyListener(new ConsoleKeyAdapter(this));
    
    this.add("Center", this.ta);
    this.pack();
    this.show();
        
    this.addWindowListener(new WindowAdapter() {
      public void windowClosing(ActionEvent e) {
	Console.this.setVisible(false);
      }
    });
  }
  
  /**
   * Write a String to Console.  The String written is concatenated
   * with a newline.
   */
  public void println(String s) {
    this.print(s+"\n");
  }
  
  /**
   * Write a line to Console.  The String written is <I>not</I>
   * concatenated with a newline.
   */
  public void print(String s) {
    this.ta.append(s);
  }
  
  /**
   * Read a line from Console.  The String returned is not terminated
   * with a newline.
   *
   * @return the String the user typed
   */
  public String readln() {
    boolean success = false;
    String temp = "";
    while (!success) {
      try {
	temp = (String)this.inputLines.dequeue();
	success = true;
      } catch (EmptyQueueException eqe) {
	try { Thread.sleep(100); }
	catch (InterruptedException ie) {}
      }
    }
    return temp;
  }
  
  /**
   * Insert a line into the user input queue.  Text inserted in this manner
   * will appear to readln() calls.
   */
  void addInputLine(String newInputLine) {
    this.inputLines.enqueue(newInputLine);
  }
  
  
  /** The KeyAdapter used by Console to record user input. */
  class ConsoleKeyAdapter extends KeyAdapter {
    
    private Console myConsole;
    private StringBuffer curInputLine;
    
    public ConsoleKeyAdapter(Console myConsole) {
      this.myConsole = myConsole;
      this.curInputLine = new StringBuffer();
    }
    
    public void keyTyped(KeyEvent e) {
      char c = e.getKeyChar();
      if (c == '\u0008' && curInputLine.length() > 0) {
	this.curInputLine.deleteCharAt(this.curInputLine.length() - 1);
	return;
      }	
      if (c == '\n') {
	// don't include newline with String
	this.myConsole.addInputLine(this.curInputLine.toString());
	this.curInputLine = new StringBuffer();
      }
      else if (e.isActionKey()) return;
      else this.curInputLine.append(c);
    }
  } 
}

/*
 * $Log: Console.java,v $
 * Revision 1.1.1.1  2002/06/05 21:56:32  root
 * CS101 comes to Olin finally.
 *
 * Revision 1.3  2000/04/30 02:33:50  mharder
 * Changed import statements to confirm to new cs101 packages.
 *
 * Revision 1.2  1999/02/08 20:52:13  tparnell
 * fixed references to Queue
 *
 * Revision 1.1  1998/07/28 17:46:19  tparnell
 * Initial revision.  Uses cs101.util.Queue as abstraction.
 *
 */