/*
	SmallWorld -- Little Smalltalk in Java
		runs as application
	Written by Tim Budd, budd@acm.org
	November 2004

	Version 0.9 November 2004
	Version 0.8 November 2002
*/

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.applet.*;
import javax.swing.*;
import java.net.*;

public class SmallWorld extends JApplet {
	static public void main (String [] args) {
		new SmallWorld(args);
	}

	private SmallInterpreter theInterpreter = new SmallInterpreter();

		// used only by applet
	public void init () { 
		setContentPane(buildPanel());
		// now read the image
		output.setText("Initializing image: wait ...."); 
		try {
			InputStream fin = new URL(getCodeBase(), "image").openStream();
			readImage(fin);
		} catch(Exception e) {
			output.setText("Applet exception " + e);
		}
		repaint();
	}

	private JPanel buildPanel() {
		JPanel p = new JPanel();
		p.setLayout(new GridLayout(4, 1));
		JButton browserButton = new JButton("class browser");
		browserButton.addActionListener(
			new doItListener("Class browser"));
		p.add(browserButton);
		JButton saveButton = new JButton("save image");
		saveButton.addActionListener(
			new doItListener("File saveImage: 'image'"));
		p.add(saveButton);
		JButton quitButton = new JButton("quit");
		p.add(quitButton);
		quitButton.addActionListener(
		new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				// maybe later do something more intelligent
				System.exit(0);
			}
		});
		p.add(output);
		return p;
	}

	private JTextField output = new JTextField();

	public SmallWorld() { } // used by applet

	public SmallWorld(String [ ] args) { // used by application

		JFrame world = new JFrame();
		world.setTitle("Small World");
		world.setSize(200, 150);
		world.addWindowListener(new WindowAdapter ( ){
			public void windowClosing (WindowEvent e) 
				{ System.exit(0); } });

		world.getContentPane().add(buildPanel());

		// now read the image
		world.show();
		output.setText("Initializing image: wait ...."); 
		world.repaint();
		try {
			if (args.length > 0)
				readImage(new FileInputStream(args[0]));
			else
				readImage(new FileInputStream("image"));
		} catch (Exception e) {
			output.setText("caught exception:" + e);
		}
		world.repaint();
	}

	
	private void readImage(InputStream name) throws Exception {
		ObjectInputStream ois = new ObjectInputStream(name);
		theInterpreter = new SmallInterpreter();
		//theInterpreter = (SmallInterpreter) ois.readObject();
		// now read object by object
		theInterpreter.nilObject = (SmallObject) ois.readObject();
		theInterpreter.trueObject = (SmallObject) ois.readObject();
		theInterpreter.falseObject = (SmallObject) ois.readObject();
		theInterpreter.smallInts = (SmallInt []) ois.readObject();
		theInterpreter.ArrayClass = (SmallObject) ois.readObject();
		theInterpreter.BlockClass = (SmallObject) ois.readObject();
		theInterpreter.ContextClass = (SmallObject) ois.readObject();
		theInterpreter.IntegerClass = (SmallObject) ois.readObject();
		output.setText("image initialized");
		done = true;
	}

	private boolean done = false;

	private class doItListener implements ActionListener {
		public doItListener(String t) { task = t;}
		private String task;
		public void actionPerformed(ActionEvent e) {
		if (! done) return; // not ready yet
		output.setText(task);
		// start from the basics
		SmallObject TrueClass = theInterpreter.trueObject.objClass;
		SmallObject name = TrueClass.data[0]; // a known string
		SmallObject StringClass = name.objClass;
		// now look for the method
		SmallObject methods = StringClass.data[2];
		SmallObject doItMeth = null;
		for (int i = 0; i < methods.data.length; i++) {
		   SmallObject aMethod = methods.data[i];
		   if ("doIt".equals(aMethod.data[0].toString()))
		     doItMeth = aMethod;
		}
		if (doItMeth == null)
			System.out.println("can't find do it!!");
		else {
			SmallByteArray rec = new SmallByteArray(StringClass, task);
			SmallObject args = new SmallObject(theInterpreter.ArrayClass, 1);
			args.data[0] = rec;
			SmallObject ctx = theInterpreter.buildContext(theInterpreter.nilObject, args, doItMeth);
			try {
			theInterpreter.execute(ctx, null, null);
			} catch(Exception ex) {
				output.setText("exception: " + ex);
				repaint();
			}
		}
		}
	}
}