//********************************************************************
//  Direction.java       Author:  Lewis and Loftus
//                       Updated: Bary W Pollack
//
//  Demonstrates key events and the use of inner classes for event
//  listeners.  Demonstrates listening for the cursor keys.
//********************************************************************

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

public class Direction extends Applet {
    //-----------------------------------------------------------------
    //  Sets up the applet by creating listeners, loading images, etc.
    //-----------------------------------------------------------------
    public void init() {
        addKeyListener(new DirectionKeyListener());

        x = (APPLET_WIDTH  - IMAGE_SIZE) / 2;
        y = (APPLET_HEIGHT - IMAGE_SIZE) / 2;
        up    = getImage(getCodeBase(), "cyanUp.gif");
        down  = getImage(getCodeBase(), "cyanDown.gif");
        left  = getImage(getCodeBase(), "cyanLeft.gif");
        right = getImage(getCodeBase(), "cyanRight.gif");

        currentImage = right;
        bonk = getAudioClip(getCodeBase(), "bonk.au");

        setBackground(Color.black);
        setSize(APPLET_WIDTH, APPLET_HEIGHT);
    }

    //-----------------------------------------------------------------
    //  Paints the current image in the current location
    //-----------------------------------------------------------------
    public void paint(Graphics page) {
        page.drawImage(currentImage, x, y, this);
        showStatus(" Click in the applet; then press cursor keys");
    }

    private final int APPLET_WIDTH  = 250;
    private final int APPLET_HEIGHT = 200;
    private final int JUMP = 5;  // increment for image movement
    private final int IMAGE_SIZE = 31;
    private Image up, down, right, left, currentImage;
    private AudioClip bonk;
    private int x, y;

    //*****************************************************************
    //  Represents a listener for keyboard activity.
    //*****************************************************************
    private class DirectionKeyListener implements KeyListener {

        //--------------------------------------------------------------
        //  Responds to the user pressing arrow keys by adjusting the
        //  image location accordingly
        //--------------------------------------------------------------
        public void keyPressed(KeyEvent event) {
            switch (event.getKeyCode()) {
                case KeyEvent.VK_UP:
                    currentImage = up;
                    if (y > 0)
                        y -= JUMP;
                    break;
                case KeyEvent.VK_DOWN:
                    currentImage = down;
                    if (y < APPLET_HEIGHT-IMAGE_SIZE)
                        y += JUMP;
                    break;
                case KeyEvent.VK_LEFT:
                    currentImage = left;
                    if (x > 0)
                        x -= JUMP;
                    break;
                case KeyEvent.VK_RIGHT:
                    currentImage = right;
                    if (x < APPLET_WIDTH-IMAGE_SIZE)
                        x += JUMP;
                    break;
                default:
                    bonk.play();
            }
            repaint();
        }

        //--------------------------------------------------------------
        //  Provide empty definitions for unused event methods
        //--------------------------------------------------------------
        public void keyTyped(KeyEvent event) { }
        public void keyReleased(KeyEvent event) { }
    }
}