package {
	import flash.display.*;
	import flash.events.*;
	import flash.utils.Timer;
	import flash.text.TextField;
 
	public class AirRaid extends MovieClip {
		private var aagun:AAGun;
		private var airplanes:Array;
		private var bullets:Array;
		public var leftArrow, rightArrow:Boolean;
		private var nextPlane:Timer;
		private var shotsLeft:int;
		private var shotsHit:int;
 
		public function startAirRaid() {
			// init score
			shotsLeft = 20;
			shotsHit = 0;
			showGameScore();
 
			// create gun
			aagun = new AAGun();
			addChild(aagun);
 
			// create object arrays
			airplanes = new Array();
			bullets = new Array();
 
			// listen for keyboard
			stage.addEventListener(KeyboardEvent.KEY_DOWN,keyDownFunction);
			stage.addEventListener(KeyboardEvent.KEY_UP,keyUpFunction);
 
			// look for collisions
			addEventListener(Event.ENTER_FRAME,checkForHits);
 
			// start planes flying
			setNextPlane();
		}
 
		public function setNextPlane() {
			nextPlane = new Timer(1000+Math.random()*1000,1);
			nextPlane.addEventListener(TimerEvent.TIMER_COMPLETE,newPlane);
			nextPlane.start();
		}
 
		public function newPlane(event:TimerEvent) {
			// random side, speed and altitude
			if (Math.random() > .5) {
				var side:String = "left";
			} else {
				side = "right";
			}
			var altitude:Number = Math.random()*50+20;
			var speed:Number = Math.random()*150+150;
 
			// create plane
			var p:Airplane = new Airplane(side,speed,altitude);
			addChild(p);
			airplanes.push(p);
 
			// set time for next plane
			setNextPlane();
		}
 
		// check for collisions
		public function checkForHits(event:Event) {
			for(var bulletNum:int=bullets.length-1;bulletNum>=0;bulletNum--){ 
				for (var airplaneNum:int=airplanes.length-1;airplaneNum>=0;airplaneNum--) {
					if (bullets[bulletNum].hitTestObject(airplanes[airplaneNum])) {
						airplanes[airplaneNum].planeHit();
						bullets[bulletNum].deleteBullet();
						shotsHit++;
						showGameScore();
						break;
					}
				}
			}
 
			if ((shotsLeft == 0) && (bullets.length == 0)) {
				endGame();
			}
		}
 
		// key pressed
		public function keyDownFunction(event:KeyboardEvent) {
			if (event.keyCode == 37) {
				leftArrow = true;
			} else if (event.keyCode == 39) {
				rightArrow = true;
			} else if (event.keyCode == 32) {
				fireBullet();
			}
		}
 
		// key lifted
		public function keyUpFunction(event:KeyboardEvent) {
			if (event.keyCode == 37) {
				leftArrow = false;
			} else if (event.keyCode == 39) {
				rightArrow = false;
			}
		}
 
		// new bullet created
		public function fireBullet() {
			if (shotsLeft <= 0) return;
			var b:Bullet = new Bullet(aagun.x,aagun.y,-300);
			addChild(b);
			bullets.push(b);
			shotsLeft--;
			showGameScore();
		}
 
		public function showGameScore() {
			showScore.text = String("Score: "+shotsHit);
			showShots.text = String("Shots Left: "+shotsLeft);
		}
 
		// take a plane from the array
		public function removePlane(plane:Airplane) {
			for(var i in airplanes) {
				if (airplanes[i] == plane) {
					airplanes.splice(i,1);
					break;
				}
			}
		}
 
		// take a bullet from the array
		public function removeBullet(bullet:Bullet) {
			for(var i in bullets) {
				if (bullets[i] == bullet) {
					bullets.splice(i,1);
					break;
				}
			}
		}
 
		// game is over, clear movie clips
		public function endGame() {
			// remove planes
			for(var i:int=airplanes.length-1;i>=0;i--) {
				airplanes[i].deletePlane();
			}
			airplanes = null;
 
			aagun.deleteGun();
			aagun = null;
 
			stage.removeEventListener(KeyboardEvent.KEY_DOWN,keyDownFunction);
			stage.removeEventListener(KeyboardEvent.KEY_UP,keyUpFunction);
			removeEventListener(Event.ENTER_FRAME,checkForHits);
 
			nextPlane.stop();
			nextPlane = null;
 
			gotoAndStop("gameover");
		}
 
	}
}
 

package {
	import flash.display.*;
	import flash.events.*;
	import flash.utils.getTimer;
 
	public class Bullet extends MovieClip {
		private var dy:Number; / / Vertical speed
		private var lastTime:int;
 
		public function Bullet(x,y:Number, Speed: Number) {
			/ / Set start position
			this.x = x;
			this.y = y;
			/ / Get speed
			dy = Speed;
			/ / Set up animation
			lastTime = getTimer();
			addEventListener(Event.ENTER_FRAME, MoveBullet);
		}
 
		public function moveBullet(event:Event) {
			/ / Get time passed
			var timePassed:int = getTimer()-lastTime;
			lastTime += TimePassed;
 
			/ / Move bullet
			this.y += Dy*timePassed/1000;
 
			/ / Bullet past top of screen
			if (this.y < 0) {
				deleteBullet();
			}
 
		}
 
		
		public function deleteBullet() {
			MovieClip(parent). RemoveBullet(this);
			parent.removeChild(this);
			removeEventListener(Event.ENTER_FRAME, MoveBullet);
		}
 
	}
}

package {
	import flash.display.*;
	import flash.events.*;
	import flash.utils.getTimer;
 
	public class Airplane extends MovieClip {
		private var dx:Number; / / Speed ​​and direction
		private var lastTime:int; / / Animation time
 
		public function Airplane(side:String, Speed:Number, Altitude:Number) {
			if (side == "Left") {
				this.x = -50; / / Start to the left
				dx = Speed; / / Fly left to right
				this.scaleX = -1; / / Reverse
			} else if (side == "Right") {
				this.x = 600; / / Start to the right
				dx = -speed; / / Fly right to left
				this.scaleX = 1; / / Not reverse
			}
			this.y = Altitude; / / Vertical position
 
			this.gotoAndStop(Math.floor(Math.random()*5+1));
			/ / Set up animation
			addEventListener(Event.ENTER_FRAME, MovePlane);
			lastTime = getTimer();
		}
 
		public function movePlane(event:Event) {
			/ / Get time passed
			var timePassed:int = getTimer()-lastTime;
			lastTime += TimePassed;
 
			/ / Move plane
			this.x += Dx*timePassed/1000;
 
			/ / Check to see if off screen
			if ((dx < 0) & & (x < -50)) {
				deletePlane();
			} else if ((dx > 0) & & (x > 600)) {
				deletePlane();
			}
 
		}
 
		/ / Plane hit, show explosion
		public function planeHit() {
			removeEventListener(Event.ENTER_FRAME, MovePlane);
			MovieClip(parent). RemovePlane(this);
			gotoAndPlay("Explode");
		}
 
		
		public function deletePlane() {
			removeEventListener(Event.ENTER_FRAME, MovePlane);
			MovieClip(parent). RemovePlane(this);
			parent.removeChild(this);
		}
 
	}
}
 

package {
	import flash.display.*;
	import flash.events.*;
	import flash.utils.getTimer;
 
	public class AAGun extends MovieClip {
		static const speed:Number = 150.0;
		private var lastTime:int; / / Animation time
 
		public function AAGun() {
			/ / Initial location of gun
			this.x = 275;
			this.y = 340;
 
			/ / Movement
			addEventListener(Event.ENTER_FRAME, MoveGun);
		}
 
		public function moveGun(event:Event) {
			/ / Get time difference
			var timePassed:int = getTimer()-lastTime;
			lastTime += TimePassed;
 
			/ / Current position
			var newx = this.x;
 
			/ / Move to the left
			if (MovieClip(parent). LeftArrow) {
				newx -= Speed*timePassed/1000;
			}
 
			/ / Move to the right
			if (MovieClip(parent). RightArrow) {
				newx += Speed*timePassed/1000;
			}
 
			/ / Check boundaries
			if (newx < 10) newx = 10;
			if (newx > 540) newx = 540;
 
			/ / Reposition
			this.x = Newx;
		}
 
		
		public function deleteGun() {
			parent.removeChild(this);
			removeEventListener(Event.ENTER_FRAME, MoveGun);
		}
	}
}