// Bug.java
// Written by THC for CS 5 Lab Assignment #2 Extra Credit.
// Represents an individual Bug.

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

public class Bug {
  private static Image[] bugImages; // array of references to the sequence of images for this Bug
  private static Applet theApplet;  // the applet that will be displaying the image
  private static final int HEIGHT = 50, WIDTH = 33; // height and width of this Bug's image
  
  private Point upperLeft;  // upper left corner of the current location of this Bug's image
  private int posture;      // index into bugImages of this Bug's posture
  private int speed;        // how many pixels this Bug moves each time
  
  // Static method to initialize the static variables bugImages and theApplet.
  public static void init(Image[] images, Applet applet) {
    bugImages = images;
    theApplet = applet;
  }
  
  // Constructor.  Makes a new Bug at the given location and with a given speed.
  public Bug(Point where, int howFast) {
    upperLeft = where;
    posture = 0;
    speed = howFast;
  }
  
  // Draw this Bug.
  public void draw(Graphics page) {
    // Which image we use depends on this Bug's posture.
    page.drawImage(bugImages[posture], upperLeft.x, upperLeft.y, theApplet);
  }
  
  // Move this Bug toward the top of the applet window and update this Bug's
  // posture to the next image in the sequence of images.
  // Returns true if any part of this Bug is still in the window,
  // false if this Bug has moved fully off the top of the window.
  public boolean move() {
    upperLeft.y -= speed;
    posture = (posture + 1) % bugImages.length;
    return upperLeft.y + HEIGHT >= 0;
  }
  
  // Determines whether a Bug is hit by a Point.
  // Returns true if the Point is anywhere within this Bug's image.
  public boolean isHit(Point p) {
    return upperLeft.x <= p.x && p.x < upperLeft.x + WIDTH
    && upperLeft.y <= p.y && p.y < upperLeft.y + HEIGHT;
  }
}