//	Theresa Walunas
//	SE 450 Section 303, Tuesday 5:45 - 9:00 pm
//	Assignment #4, Due Date 5/09/00
//	Source File Name: FallingStar2.java   Class File: FallingStar2.class
//	Adding GUI widgits to class developed in Assignment#3:  FallingStar Class
//	This class, FallingStar2.class contains four protected classes that
//	manage the Start and Stop buttons (ButtonHandler), the Choice widget
//	that selects the color of the star polygon (StarColorChoiceHandler),
//	the check box group widget that selects the background color
//	(BckGrndColorChkBoxHandler) and the MouseClickHandler class which 
//	implements the MouseListener interface and allows the corner of the
//	3D box that is changing size to be moved to the point on the canvas
//	where the mouse button was clicked.  The FallingStarCanvas object is
//	the animated applet in a Canvas object.  It's class file is separate.
//	FallingStar2.class also provides the layout parameters and instructions
//	in the FallingStar2 constructor.

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

public class FallingStar2 extends java.applet.Applet implements Runnable{

	// Create objects to be inserted into FallingStar2 layout handlers
	protected FallingStarCanvas canvas;	// Object containing FallingStar animation
	protected Panel controlPanel;		// Panel containing Start/Stop and Choice Widgets
	protected Panel bottomPanel;		// Panel containing controlPanel and sky panels
	protected Panel sky;			// Panel containing skycolor check boxes
	protected Label Title;			// Title for box, North position
	protected Label Instructions;		// Instructions for mouse click, in bottomPanel

	// Define font objects
	protected Font titlefont = new Font("Helvetica", Font.BOLD, 24); 
	protected Font buttonfont = new Font("Helvetica", Font.PLAIN, 16);
	protected Font choicefont = new Font ("Helvetica", Font.PLAIN, 12);

	// Define buttons
	protected static final int START = 1;
	protected static final int STOP = 2;

	// Applet control elements
	Thread FallingThread;
	int delay;

	// Implements button actions. Clicking "Stop" stops the applet.
	// Clicking "Start" starts the applet from the beginning.
	protected class ButtonHandler implements ActionListener {
	
		private int cmd = 0;
	
		public ButtonHandler(int cmd){
			this.cmd = cmd;
		}

		public void actionPerformed (ActionEvent event) {
			switch (cmd){
			case START:
				start();
				break;
			case STOP:
				stop();
				break;
			}
		}
	}

	// Implements choice widget.  Clicking indicated colors changes
	// polygon star object to fill with the indicated color.  Clicking
	// "Random" causes a random color to be selected using r,g,b codes.
	protected class StarColorChoiceHandler implements ItemListener {

		public void itemStateChanged(ItemEvent event){
			Choice choice = (Choice) event.getSource();
			if (choice != null){
				if ("Light Gray".equals(event.getItem())){
					canvas.setStarColor(Color.lightGray);
				} else if ("Magenta".equals(event.getItem())){
					canvas.setStarColor(Color.magenta);
				} else if ("Yellow".equals(event.getItem())){
					canvas.setStarColor(Color.yellow);
				} else if ("Cyan".equals(event.getItem())){
					canvas.setStarColor(Color.cyan);
				} else if ("Green".equals(event.getItem())){
					canvas.setStarColor(Color.green);
				} else if ("Random".equals(event.getItem())){
					canvas.setStarColor(new Color((int)(Math.random()*256), (int)(Math.random()*256),
					(int)(Math.random()*256)));
				}
			}
		}
	}

	// Implements Check Box widget.  Checkboxes are in a group and thus only
	// one box can be true at any one time.  If "Night" is true, then the
	// background is black. If "Day" is true, then the background is yellow
	protected class BckGrndColorChkBoxHandler implements ItemListener {

		public void itemStateChanged(ItemEvent event){
			Checkbox Ckbx = (Checkbox) event.getSource();
			if (Ckbx != null) {
				if ("Night".equals(event.getItem())){
					canvas.setBckGrndColor (Color.black);
				} else if ("Day".equals(event.getItem())){
					canvas.setBckGrndColor (new Color (255, 255, 204));
				}
			}
		}
	}

	// Implements the MouseListener.  The only method that is used is the
	// mouseClicked method.  When the portion of the applet containing the
	// FallingStar animation is clicked on, the top left corner of the 
	// 3D recangle object in the animation is moved there.
	protected class MouseClickHandler implements MouseListener {

		public void mouseClicked (MouseEvent event){
			Point p = event.getPoint();
			canvas.setRectPosition(p);
		}

		// Must be defined but will not be used.
		public void mouseEntered (MouseEvent event){}
		public void mouseExited (MouseEvent event){}
		public void mousePressed (MouseEvent event){}
		public void mouseReleased (MouseEvent event){}
	}

	public FallingStar2 (){
		// Creates main Layout
		setLayout (new BorderLayout());
		canvas = new FallingStarCanvas();
		add ("Center", canvas);
		Title = new Label("Catch a Falling Star", Label.CENTER);
		Title.setFont(titlefont);
		Title.setColor(Color.green);
		add ("North", Title);

		// Creates panel for controls.
		bottomPanel = new Panel();
		bottomPanel.setLayout(new GridLayout(0,1));
		controlPanel = new Panel();
		controlPanel.setLayout(new FlowLayout());
		
		// Add Start Button
		Button startButton = new Button ("Start");
		startButton.setFont(buttonfont);
		controlPanel.add(startButton);
		
		// Add Stop Button
		Button stopButton = new Button ("Stop");
		stopButton.setFont(buttonfont);
		controlPanel.add(stopButton);
		
		// Create Choice widget and add color choices
		Choice starcolor = new Choice();
		starcolor.setFont(choicefont);
		starcolor.addItem("Cyan");
		starcolor.addItem("Green");
		starcolor.addItem("Light Gray");
		starcolor.addItem("Magenta");
		starcolor.addItem("Yellow");
		starcolor.addItem("Random");
		controlPanel.add(starcolor);

		// Create check box widgets and group
		sky = new Panel();
		sky.setLayout(new GridLayout(1,0));
		CheckboxGroup skycolor = new CheckboxGroup();
		Checkbox night = new Checkbox("Night", skycolor, true);
		Checkbox day = new Checkbox("Day", skycolor, false);
		night.setFont(buttonfont);
		day.setFont(buttonfont);
		sky.add(night);
		sky.add(day);
		controlPanel.add(sky);
		
		// Create instruction label
		bottomPanel.add(controlPanel);
		Instructions = new Label ("Click Anywhere to Move Box to that Location", Label.CENTER);
		bottomPanel.add(Instructions);

		// Add all controls to "South" in top level border layout
		add ("South", bottomPanel);

		// Register the listeners to the appropriate objects
		startButton.addActionListener(new ButtonHandler(START));
		stopButton.addActionListener(new ButtonHandler(STOP));
		
		starcolor.addItemListener(new StarColorChoiceHandler());
		
		day.addItemListener (new BckGrndColorChkBoxHandler());
		night.addItemListener (new BckGrndColorChkBoxHandler());

		canvas.addMouseListener (new MouseClickHandler());
	}

	public void init(){		

		// Parameterized frames per second (fps)
		String frames = getParameter ("fps");
		if (frames != null){
			delay = 1000/Integer.parseInt(frames);
		} else {
			delay = 100;
		}
		doLayout();
		canvas.init();
	}
		
	public void start(){
		if (FallingThread == null){
			FallingThread = new Thread(this);
			FallingThread.start();
		}
	}

	public void stop(){
		if (FallingThread != null){
			FallingThread = null;
		}
	}
 
	public void run(){
		while (Thread.currentThread() == FallingThread){
			try {
				Thread.currentThread().sleep(delay);
			}
			catch (InterruptedException e){}
			canvas.repaint();
		}
	}
}