/* this code from "The Java Tutorial Second Edition" by Mary Campione and 
 * Kathy Walrath, copywright 1998 by Sun Microsystems, Inc. 
 */

import java.awt.*;
import java.applet.Applet;

class ImageCanvas extends Canvas {
  Container pappy;
  Image image;
  Dimension size;
  int w, h;
  boolean trueSizeKnown;
  MediaTracker tracker;

  public ImageCanvas (Image image, Container highestContainer,
		      int initialWidth, int initialHeight) {
    if (image == null) {
      System.err.println("Canvas got invalid image" + " object!");
      return;
    }
    this.image = image;
    this.pappy = highestContainer;
    w = initialWidth;
    h = initialHeight;

    tracker = new MediaTracker(this);
    tracker.addImage(image, 0);

    size = new Dimension(w,h);

  }

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

  public void paint (Graphics g) {
    if (image != null) {
      if (!trueSizeKnown) {
	int imageWidth = image.getWidth(this);
	int imageHeight = image.getHeight(this);

	if (tracker.checkAll(true)) {
	  trueSizeKnown = true;
	  if (tracker.isErrorAny()) {
	    System.err.println("Error loading image: " + image);
	  }
	}
	//Component-initiated resizing.
	if (((imageWidth > 0) && (w != imageWidth)) ||
	    ((imageHeight > 0) && (h != imageHeight))) {
	  w = imageWidth;
	  h = imageHeight;
	  size = new Dimension(w,h);
	  setSize(w, h);
          pappy.setSize(w,h);
	  pappy.validate();
	}
      }
    }
    
    g.drawImage(image, 0, 0, this);
    g.drawRect(0, 0, w-1, h-1);
  }
}