/*
 * @(#)PerformanceMonitor.java	1.18 98/06/29
 *
 * Copyright 1998 by Sun Microsystems, Inc.,
 * 901 San Antonio Road, Palo Alto, California, 94303, U.S.A.
 * All rights reserved.
 *
 * This software is the confidential and proprietary information
 * of Sun Microsystems, Inc. ("Confidential Information").  You
 * shall not disclose such Confidential Information and shall use
 * it only in accordance with the terms of the license agreement
 * you entered into with Sun.
 */


import java.awt.*;
import com.sun.java.swing.JPanel;
import com.sun.java.swing.border.EtchedBorder;
import com.sun.java.swing.border.TitledBorder;
import java.awt.font.TextLayout;
import java.awt.font.FontRenderContext;
import java.awt.image.BufferedImage;
import java.awt.geom.Rectangle2D;


/**
 * Displays the time for a J2DCanvas to paint. Displays the number
 * of frames per second on animated demos.  Up to for J2DCanvases
 * are displayed.
 */
public class PerformanceMonitor extends JPanel {

    PerformanceMonitorCanvas pmc;

    public PerformanceMonitor() {
	setLayout(new BorderLayout());
	setBorder(new TitledBorder(new EtchedBorder(), "Performance"));
	pmc = new PerformanceMonitorCanvas();
	add(pmc);
    }

public class PerformanceMonitorCanvas extends Canvas implements Runnable {

    public Thread thread;
    private BufferedImage offImg;
    private Font font = new Font("Times New Roman", Font.PLAIN, 12);
    private JPanel panel;


    public PerformanceMonitorCanvas() {
	setBackground(Color.black);
	start();
    }

    public Dimension getMinimumSize() {
	return getPreferredSize();
    }

    public Dimension getMaximumSize() {
	return getPreferredSize();
    }

    public Dimension getPreferredSize() {
	TextLayout tl = new TextLayout("Nothing",font,
	    new FontRenderContext(null, false, false));
  	int h = (int)(tl.getAscent()+tl.getDescent());
	return new Dimension(140,4+h*4);
    }

    public void paint(Graphics g) {
        if (offImg != null)
            g.drawImage(offImg, 0, 0, this);
    }

    public void start() {
        thread = new Thread(this);
        thread.setPriority(Thread.MIN_PRIORITY);
	thread.setName("PerformanceMonitor");
        thread.start();
    }

    public synchronized void stop() {
        thread = null;
	notify();
    }

    public void setup(JPanel panel) {
	this.panel = panel;
    }

    public void run() {

	Thread me = Thread.currentThread();

        while (thread == me && !isShowing() || getSize().width == 0) {
	    try {
	        thread.sleep(999);
	    } catch (InterruptedException e) { thread = null; return; }
	}

        offImg = (BufferedImage) createImage(getSize().width, getSize().height);
	Graphics2D offG = offImg.createGraphics();
	offG.setFont(font);
	FontMetrics fm = offG.getFontMetrics();
	int ascent = fm.getAscent();
	int descent = fm.getDescent();
	Dimension d = getSize();


        while (thread == me && isShowing()) {

	    try {
	        thread.sleep(999);
	    } catch (InterruptedException e) { thread = null; return; }

	    offG.setBackground(getBackground());
            offG.clearRect(0, 0, d.width, d.height);
	    offG.setColor(Color.green);
	    if (panel == null)
		continue;
	    Component cmps[] = panel.getComponents();
	    int ssH = 1;
	    for (int i = 0; i < cmps.length; i++) {
	        if (cmps[i] instanceof CanvasPanel) {
	            CanvasPanel cp = (CanvasPanel) cmps[i];
	            if (cp.canvas != null && cp.canvas.perfStr != null) {
                        ssH += ascent;
                	offG.drawString(cp.canvas.perfStr, 4, ssH+1);
                        ssH += descent;
		    }
		}
	    }
            if (isShowing()) {
	        Graphics g = getGraphics();
		if (g == null)
		    continue;
	        paint(g);
	        g.dispose();
            }
        }
	thread = null;
    }
} // End PerformanceMonitorCanvas
} // End PeformanceMonitor