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

public class Roasteroids extends Applet implements CollisionHandler {

	Panel topPanel, bottomPanel;
	Label scoreLabel, shipsLabel, copyright;
	Button startButton;
	int score, ships, level;
	int rocksToGo;
	boolean gameRunning, inHyperspace;
	SpriteWorld world;
	Sequence bigRoastSeq, medRoastSeq,
			 smallRoastSeq, shipSeq, boomSeq;
	ShipSprite ship;
	Image shotImg;
	int shotLaunchX, shotLaunchY;
	MediaTracker appletTracker;
	int nextFreebie;

	final static float PI = (float) Math.PI;
	final static float ONEPOINTFIVEPI = (float) (1.5D * Math.PI);
	final static float TWOPI = (float) (2.0D * Math.PI);
	final static float THREEPI = (float) (3.0D * Math.PI);
	final static float FOURPI = (float) (4.0D * Math.PI);
	final static int START_SHIPS = 3;
	final static int FREEBIE_INTERVAL = 5000;
	final static int ROT_CLOCKWISE = (int)'x';
	final static int ROT_COUNTERCLOCKWISE = (int)'z';
	final static int THRUST = (int)'m';
	final static int FIRE = (int)',';
	final static int HYPERSPACE = (int)'.';

	Random rand = new Random();


	public final String getAppletInfo() {
		return ("(c) 1997 Chris Adamson, plucky@mindspring.com, http://www.mindspring.com/~plucky/");
	}
	
	public final void init() {		
		world = new SpriteWorld (this);
		world.setBackground (Color.black);
		doLayout();
		getImages();
		gameRunning = false;
		startButton.setLabel ("Start");
		world.start();
	} // init
	
	
	public final void start() {		

		this.showStatus ("z/x rotate  m thrusts  , fires  . warps");

	} // start
	
	protected final void getImages() {
		shotImg = getImage (getDocumentBase(), "images/shot0.gif");
		appletTracker = new MediaTracker(this);
		appletTracker.addImage (shotImg, 2);		
		
		bigRoastSeq = new Sequence ("images/lroaster", 16, this);
		medRoastSeq = new Sequence ("images/mroaster", 16, this);
		smallRoastSeq = new Sequence ("images/sroaster", 16, this);
		shipSeq = new Sequence ("images/ship", 36, this);
		boomSeq = new Sequence ("images/boom", 10, this);

		try { appletTracker.waitForID (2); }
		catch (InterruptedException e) { }
		
		shotLaunchX = shipSeq.imageAt(0).getWidth(this) / 2;
		shotLaunchY = shipSeq.imageAt(0).getHeight(this) / 2;
	} // getImages
	
	
	public void stop() {		
		super.stop();
		world.stop();
	} // stop
	
	private final void startGame() {
		score = 0;
		ships = START_SHIPS;
		nextFreebie = FREEBIE_INTERVAL;
		scoreLabel.setText (Integer.toString (score));
		shipsLabel.setText (Integer.toString (ships));
		level = 1;
		ship = new ShipSprite (shipSeq, world, world.getWidth() / 2,
									world.getHeight() / 2, PI, 0, PI);
		inHyperspace = false;
		world.add (ship);		
		gameRunning = true;
	} // startGame
	
	private final void startLevel () {
		rocksToGo = (level + 3) * 7; // how many hits until level ends

		for (int counter = 0; counter < level + 3; counter++) {
			if ((rand.nextInt() % 2) == 0) {
				world.add ( new AnimatedSprite (bigRoastSeq, world,
									0 - bigRoastSeq.imageAt(0).getWidth(this),
									rand.nextInt() % world.getHeight(),
									rand.nextInt() % PI + PI,
									70f, 5, true, true));
			} else {
				world.add ( new AnimatedSprite (bigRoastSeq, world,
									rand.nextInt() % world.getWidth(),
									0 - bigRoastSeq.imageAt(0).getHeight(this),
									rand.nextInt() % PI + PI,
									70f, 5, false, true));
			} // if-else that picks either forwards or backwards rotation
		} // for
	} //start Level
	
	private final void doLayout() {
		this.setBackground (Color.black);
		this.setForeground (Color.white);

		topPanel = new Panel();
		bottomPanel = new Panel();	
		startButton = new Button ("Loading...");
		scoreLabel = new Label ("0", Label.LEFT);
		shipsLabel = new Label (Integer.toString (START_SHIPS), Label.LEFT);
		copyright = new Label ("(c)1997 Chris Adamson");

		topPanel.setLayout (new GridLayout (1, 4, 0, 0));
		bottomPanel.setLayout (new GridLayout (1, 2, 0, 0));
		
		topPanel.add (new Label ("Score: ", Label.RIGHT));
		topPanel.add (scoreLabel);
		topPanel.add (new Label ("Ships: ", Label.RIGHT));
		topPanel.add (shipsLabel);
		
		bottomPanel.add (copyright);
		bottomPanel.add (startButton);
		
		this.setLayout (new BorderLayout() );
		this.add ("North", topPanel);
		this.add ("South", bottomPanel);
		this.add ("Center", world);
		
		this.validate();
				
	} //do Layout
	
	public final void collision (HardlySprite sprite1, byte flags) {

	
		if (flags == CollisionHandler.EAST) {
			sprite1.setX (0 - sprite1.getWidth());
		}	
		if (flags == CollisionHandler.SOUTH) {
			sprite1.setY (0 - sprite1.getHeight());
		}		
		if (flags == CollisionHandler.WEST) {
			sprite1.setX (world.getWidth());
		}	
		if (flags == CollisionHandler.NORTH) {
			sprite1.setY (world.getHeight());
		}	
	} // collision with edge of screen
	
	public final boolean collision (HardlySprite sprite1, HardlySprite sprite2) {
		if ((sprite1 instanceof BoomSprite) || 
			 (sprite2 instanceof BoomSprite)) {
		 	 return true;
		 } else if ((sprite1 instanceof ShotSprite) && 
			 (sprite2 instanceof AnimatedSprite)) {
		 	breakRock ((ShotSprite) sprite1, (AnimatedSprite) sprite2);
			world.remove (sprite1);
		 	return false;
		} else if ((sprite1 instanceof AnimatedSprite) && 
					(sprite2 instanceof ShotSprite)) {
			breakRock ((ShotSprite) sprite2, (AnimatedSprite) sprite1);
			world.remove (sprite2);
			return false;
		} else if (((sprite1 instanceof AnimatedSprite) && 
					(sprite2 instanceof ShipSprite)) ||
					((sprite1 instanceof ShipSprite) &&
					(sprite2 instanceof AnimatedSprite))) {
			playerDies();
			return true;
		} else {

			return false;
		}// if-else-else

	} // two-sprite collision
	
	private final void breakRock (ShotSprite shot, AnimatedSprite victim) {
		int impactX, impactY;
		
		impactX = (int) shot.getX();
		impactY = (int) shot.getY();

		world.add (new BoomSprite (boomSeq, world, impactX, impactY,
					7));
		rocksToGo--;
		
		if (victim.getSequence() == smallRoastSeq) {
			addToScore (100);
			world.remove(victim);
			if (rocksToGo == 0) {
				advanceLevel();
			}
			return;
		} else if (victim.getSequence() == medRoastSeq) {
			addToScore (50);
			world.add (new AnimatedSprite (smallRoastSeq, world,
						impactX, impactY, rand.nextInt() % TWOPI,
						rand.nextFloat() * 10 + 70f, rand.nextInt() % 3 + 7,
						true, true));
			world.add (new AnimatedSprite (smallRoastSeq, world,
						impactX, impactY, rand.nextInt() % TWOPI,
						rand.nextFloat() * 10 + 70f, rand.nextInt() % 3 + 7,
						false, true));
			world.remove(victim);
			return;
		} else if (victim.getSequence() == bigRoastSeq) {
			addToScore (20);
			world.add (new AnimatedSprite (medRoastSeq, world,
						impactX, impactY, rand.nextInt() % TWOPI,
						rand.nextFloat() * 10 + 80f, rand.nextInt() % 5 + 9,
						true, true));
			world.add (new AnimatedSprite (medRoastSeq, world,
						impactX, impactY, rand.nextInt() % TWOPI,
						rand.nextFloat() * 10 + 80f, rand.nextInt() % 5 + 9,
						false, true));
			world.remove(victim);
			return;
		}
	} // breakRock
	
	private final void playerDies() {
		int boomX, boomY;

		if (!ship.isExploding()) {
			boomX = (int) ship.getX();
			boomY = (int) ship.getY();
			world.add (new BoomSprite (boomSeq, world, boomX,
										boomY, 5));
			ship.explode();
			ships--;
			shipsLabel.setText (Integer.toString (ships));
			if (ships == 0) { endGame(boomX, boomY); }
		} // if ship not already exploding
	} //playerDies
	
	private final void endGame (int boomX, int boomY) {
		world.removeAll();
		world.clearScreen();
		world.add (new BoomSprite (boomSeq, world, boomX, boomY, 5));
		ship = null;
		gameRunning = false;
	} //endGame
	
	
	public final boolean keyDown(Event evt, int key) {
		try {
			if (key == ROT_COUNTERCLOCKWISE) {
				ship.rotateCounterclockwise();
				return true;
			} else if (key == ROT_CLOCKWISE) {
				ship.rotateClockwise();
				return true;
			} else if (key == THRUST) {
				ship.thrust();
				return true;
			} else if (key == HYPERSPACE) {
				hyperspace();
				return true;
			} else { return super.keyDown (evt, key);}
		} catch (NullPointerException e) { } // ignore NPE if keyUp before ship created
		return super.keyDown (evt, key); // this will never be executed, but compiler doesn't like where I put my try-catch
	} //keyDown
	
	public final boolean keyUp (Event evt, int key) {
		try {
			if ((key == ROT_COUNTERCLOCKWISE) || (key == ROT_CLOCKWISE)) {
				ship.stopRotating();
				return true;
			}  else if (key == FIRE) {
				if (ship.isExploding()) { return true; }
				fire();
				return true;
			} else if (key == THRUST) {
				ship.stopThrusting();
				return true;
			} else if (key == HYPERSPACE) {
				inHyperspace = false;
				return true;
			} else {
				return super.keyUp (evt, key);
			}
		} catch (NullPointerException e) { } // ignore NPE if keyUp before ship created
		return super.keyDown (evt, key); // this will never be executed, but compiler doesn't like where I put my try-catch
	} //keyUp
	

	protected void addToScore (int newPoints) {
		score += newPoints;
		scoreLabel.setText (Integer.toString(score));
		if (score > nextFreebie) {
			ships++;
			shipsLabel.setText (Integer.toString (ships));
			nextFreebie += FREEBIE_INTERVAL;
		}
	} // addToScore
	
	public final boolean action (Event e, Object arg) {
		if (e.target == startButton) {
			if (!gameRunning) {
				startGame();
				startLevel();
				return true;
			} else {
				// handle pause button
				return true;
			}
		} else {
			return super.action (e, arg);
		}//if-else
	}// action
	
	private final void fire() {
		world.add (new ShotSprite (shotImg, world,
		(int) (ship.getX() + shotLaunchX),
		(int) (ship.getY() + shotLaunchY),
		ship.getPointing(), 250));	
	}
	
	private final void hyperspace() {
		if (!ship.isExploding() && !inHyperspace) {
			inHyperspace = true;
			world.remove(ship);
			ship.setX (rand.nextFloat() * world.getWidth());
			ship.setY (rand.nextFloat() * world.getHeight());
			world.add (ship);
		}
	}
	
		
	private final void advanceLevel () {
		level++;
		startLevel();
	} //advanceLevel
	
} // Roasteroids