// David Eppstein, UC Irvine, 11 Jun 1997
//
// Disableable button with 3d appearance

import java.awt.*;
import gui.*;

public abstract class ThreeStateButton extends Canvas {
	static Font font = null;				// for button labels
	static FontMetrics metric = null;
	static final int margin = 4;

	String text;
	int width, height;
	boolean depressed;
	boolean enabled;
	Color disColor;

	public ThreeStateButton(String s) {
		if (font == null) {
			font = new Font("Helvetica",Font.BOLD,12);
			metric = PatchFontMetrics.patch(getFontMetrics(font));
		}
		text = s;
		width = metric.stringWidth(s) + 2*margin;
		height = metric.getHeight() + 2*margin;
		depressed = false;
		enabled = true;
	}

	public Dimension minimumSize() { return new Dimension(width, height); }
	public Dimension preferredSize() { return minimumSize(); }

	public void enable() { enabled = true; repaint(); }
	public void disable() { enabled = false; repaint(); }

	public void setDisableColor(Color c) { disColor = c; }
	
	boolean inRange(int x, int y) { return (x >= 0 && x < width && y >= 0 && y < height); }
	public boolean mouseDown(Event ev, int x, int y) {
		if (inRange(x, y) && enabled) {
			depressed = true;
			repaint();
		}
		return true;
	}
	public boolean mouseUp(Event ev, int x, int y) {
		if (inRange(x, y) && depressed && enabled) action();
		depressed = false;
		repaint();
		return true;
	}
	
	public void paint(Graphics g) {
		g.setColor(getBackground());
		g.fillRect(1,1,width-3,height-3);
		g.draw3DRect(1, 1, width-3, height-3, !depressed);
		Color c;
		if (enabled) c = getForeground();
		else c = disColor;
		g.setColor(c);
		g.drawRect(0, 0, width-1, height-1);
		g.setFont(font);
		g.drawString(text, margin, height - margin - metric.getDescent());
	}
	
	// shortcut for combining standard initialization routines
	void colorize(Color bg, Color fg, Color dc, Container c) {
		setBackground(bg);
		setForeground(fg);
		setDisableColor(dc);
		c.add("", this);
	}

	// do whatever it is the button is supposed to do
	public abstract void action();
}