import java.awt.AWTEvent;
import java.awt.AWTEventMulticaster;
import java.awt.event.ActionListener;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.*;

/**
 * a lightweight button which holds 3 image states, 1 for no-focus, 1 for focus and 1 for pressed.
 */
public class ImageButton extends ImageLabel {

 /**
  * the 'focused' image
  */
  Image imageFocus = null;
  
 /**
  * the 'pressed' image
  */
  Image imagePress = null;
  
 /**
  * button state
  */
  boolean press;
  
 /**
  * mouse/pointer state (inside this button's boundaries)
  */
  boolean inside;
  
 /**
  * used for posting action events to listeners
  */
  ActionListener actionListener;

 /**
  * construct a new ImageButton, and enable Mouse events for this component
  */
  public ImageButton() {
    super();
    this.enableEvents(AWTEvent.MOUSE_EVENT_MASK);
  }
  
 /**
  * set the 'focused' image
  */
  public void setImageFocus(String imageFilename) throws InterruptedException {
    imageFocus = Utils.getImage(imageFilename);
  }
  
 /**
  * set the 'pressed' image
  */
  public void setImagePress(String imageFilename) throws InterruptedException {
    imagePress = Utils.getImage(imageFilename);
  }

  
 /**
  * draw the image onto the Graphics context based upon the state variables 'inside' and 'press'.
  */
  public void paint(Graphics g) {
    if (inside && !press && imageFocus != null) {
      g.drawImage(imageFocus,getLocation().x,getLocation().y,getSize().width,getSize().height,null);
    }
    else if (press) {
      g.drawImage(imagePress,getLocation().x,getLocation().y,getSize().width,getSize().height,null);
    }
    else {
      g.drawImage(image,getLocation().x,getLocation().y,getSize().width,getSize().height,null);
    }

  }

 /**  
  * set the specified listener for this component
  */
  public void addActionListener(ActionListener listener) {
    actionListener = AWTEventMulticaster.add(actionListener, listener);
    enableEvents(AWTEvent.MOUSE_EVENT_MASK);
  }
 
 /**
  * remove the specified listener
  */
  public void removeActionListener(ActionListener listener) {
    actionListener = AWTEventMulticaster.remove(actionListener, listener);
  }
   
 /**
  * handler for mouse events
  */
  public void processMouseEvent(MouseEvent e) {
     
    // the button was clicked
    if (e.getID() == MouseEvent.MOUSE_PRESSED) {
      press = true;

      repaint();
      
      // notify listeners
      if(actionListener != null) {
        actionListener.actionPerformed(new ActionEvent(this, ActionEvent.ACTION_PERFORMED, ""));
      }
      
    }
    // end of button press
    else if(e.getID() == MouseEvent.MOUSE_RELEASED) {
      press = false;
      repaint();
    }
    // the mouse has entered the boundaries of the button
    else if (e.getID() == MouseEvent.MOUSE_ENTERED) {
      inside = true;
      repaint();
    }
    // the mouse has exited the boundaries of the button    
    else if (e.getID() == MouseEvent.MOUSE_EXITED) {
      inside = false;
      repaint();
    }

    // Pass unhandled events to superclass.
    super.processMouseEvent(e); 
  }
    
}