var UpgradeItemContainer = Container.expand(function (upgradeType, labelText, onClickCallback) {
	var self = Container.call(this);
	var bg = self.createAsset('upgradeItemBg', 'Upgrade Item Background', 0.5, 0.5);
	bg.width = LK.gui.width * 0.6;
	bg.height = 245;
	bg.x = LK.gui.width / 2;
	bg.y = 75;
	self.addChild(bg);
	var text = new Text2(labelText, {
		size: 50,
		fill: '#006600',
		weight: 'bold'
	});
	text.anchor.set(0, 0.5);
	text.x = LK.gui.width / 2 - bg.width / 2 + 50;
	text.y = 10;
	var priceText = new Text2('0', {
		size: 50,
		fill: '#000000',
		weight: 'bold',
		align: 'center'
	});
	priceText.anchor.set(0, 0.5);
	self.addChild(text);
	self.addChild(priceText);
	var button = self.createAsset('upgradeButton', 'Upgrade Button', 0.5, 0.5);
	button.x = LK.gui.width / 2 + bg.width / 2 - 50;
	button.y = bg.height / 2 - 47;
	pulsate(button, 1.02, 0.001);
	self.addChild(button);
	var dotContainer = new Container();
	var dots = [];
	for (var i = 0; i < 10; i++) {
		var dot = self.createAsset('dot', 'Dot Image', 0.5, 1);
		dot.x = i * 55;
		dot.scale.x = 3;
		dot.y = 0;
		dots.push(dot);
		dotContainer.addChild(dot);
	}
	dotContainer.x = LK.gui.width / 2 - bg.width / 2 + 70;
	dotContainer.y = bg.height - 80;
	self.addChild(dotContainer);
	var coinSprite = self.createAsset('coinSprite', 'Coin Sprite', 0, 0.5);
	coinSprite.x = text.x - 2;
	coinSprite.y = text.y + 82;
	priceText.x = coinSprite.x + coinSprite.width + 20;
	priceText.y = coinSprite.y + 2;
	self.addChild(coinSprite);
	button.on('down', function () {
		self.buy();
		onClickCallback(upgradeType);
	});
	var price = 1;
	self.update = function () {
		priceText.setText(Math.ceil(price));
		for (var i = 0; i < dots.length; i++) {
			var d = dots[i];
			console.log(upgradeType, upgrades[upgradeType]);
			upgrades[upgradeType] > i ? d.tint = 0x00ee00 : d.tint = 0x555555;
		}
	};
	self.buy = function () {
		price *= 1.5;
		upgrades[upgradeType]++;
		self.update();
	};
	self.update();
});
var UpgradeContainer = Container.expand(function () {
	var self = Container.call(this);
	var upgradeBg = self.createAsset('upgradeBg', 'Upgrade Background', 0, 0);
	var h = LK.gui.height;
	var w = LK.gui.width;
	upgradeBg.width = w;
	upgradeBg.height = h;
	self.addChild(upgradeBg);
	var upgradeTitleText = new Text2('Upgrades', {
		size: 100,
		fill: '#000000',
		weight: 'bold'
	});
	upgradeTitleText.anchor.set(0.5, 0.5);
	upgradeTitleText.x = w / 2;
	upgradeTitleText.y = 150;
	self.addChild(upgradeTitleText);
	var u1 = new UpgradeItemContainer('snowballs', 'Extra snowball', function () {});
	self.addChild(u1);
	var u2 = new UpgradeItemContainer('strength', 'Strength', function () {});
	self.addChild(u2);
	var u3 = new UpgradeItemContainer('gifts', 'Gift', function () {
		self.getGameInstance().placeGift();
	});
	self.addChild(u3);
	u1.y = 350;
	u2.y = u1.y + 320;
	u3.y = u2.y + 320;
	var playButton = self.createAsset('playButton', 'Play Button', 0.5, 0.5);
	pulsate(playButton, 1.05);
	playButton.x = w / 2;
	playButton.y = h - 350;
	self.addChild(playButton);
	playButton.on('down', function () {
		self.getGameInstance().startNextWave();
		self.destroy();
	});
});
var IntroScreen = Container.expand(function () {
	var self = Container.call(this);
	var upgradeBg = self.createAsset('introBg', 'Intro Screen Background', 0, 0);
	var h = LK.gui.height;
	var w = LK.gui.width;
	upgradeBg.width = w;
	upgradeBg.height = h;
	self.addChild(upgradeBg);
	var infoText = new Text2('Throw snowballs at kids to save Christmas!', {
		size: 60,
		fill: '#ffffff',
		weight: 700,
		align: 'center'
	});
	infoText.anchor.set(0.5, 0.5);
	infoText.x = w / 2;
	infoText.y = 120;
	self.addChild(infoText);
	var playButton = self.createAsset('playButton', 'Play Button', 0.5, 0.5);
	playButton.x = w / 2;
	playButton.y = h - 250;
	var playButton2 = self.createAsset('playButton', 'Play Button', 0.5, 0.5);
	playButton2.x = w / 2;
	playButton2.y = h - 250;
	self.addChild(playButton2);
	self.addChild(playButton);
	playButton.blendMode = 2;
	playButton2.blendMode = 1;
	playButton.on('down', function () {
		LK.gui.removeChild(self);
		self.destroy();
		self.getGameInstance().startNextWave();
	});
	pulsate(playButton2, 1.1);
	pulsate(playButton, 1.05);
});
var WaveCounterText = Container.expand(function (level) {
	var self = Container.call(this);
	var text = new Text2('Wave ' + level, {
		size: 150,
		weight: 700,
		fill: "#005500"
	});
	text.anchor.set(.5, .5);
	text.x = 2048 / 2;
	text.y = 2732 / 2;
	self.addChild(text);
	var maxScale = 1.1;
	var minScale = 0.9;
	var scaleStep = 0.005;
	var growing = true;
	self.scale.x = self.scale.y = minScale;
	LK.on('tick', function () {
		if (growing) {
			text.scale.x += scaleStep;
			text.scale.y += scaleStep;
			if (text.scale.x >= maxScale) growing = false;
		} else {
			text.scale.x -= scaleStep;
			text.scale.y -= scaleStep;
			if (text.scale.x <= minScale) growing = true;
		}
	});
	LK.setTimeout(function () {
		var fadeStep = 0.05;
		var fadeInterval = LK.setInterval(function () {
			text.alpha -= fadeStep;
			if (text.alpha <= 0) {
				LK.clearInterval(fadeInterval);
				self.destroy();
			}
		}, 1000 / 60);
	}, 3000);
});
var Wallet = Container.expand(function () {
	var self = Container.call(this);
	self.setCoinText = function (coinCount) {
		self.coinText.setText(coinCount.toString());
	};
	var walletBackground = self.createAsset('walletBg', 'Wallet Background', .5, .5);
	var walletForeground = self.createAsset('walletFg', 'Wallet Foreground', 1, .5);
	walletForeground.scale.x = walletForeground.scale.y = .7;
	self.init = function () {
		self.x = 1418 - walletBackground.width / 2;
		self.y = 110;
		self.coinText = new Text2('0', {
			size: 70,
			fill: '#000000',
			align: 'center'
		});
		self.coinText.x = walletForeground.x + 65;
		self.coinText.y = walletForeground.y;
		self.coinText.anchor.set(1, 0.5);
		self.addChild(self.coinText);
		LK.gui.addChildAt(self, LK.gui.children.length);
	};
});
var CoinLayer = Container.expand(function () {
	var self = Container.call(this);
	self.coins = [];
	self.x = 0;
	self.y = 0;
	self.addCoin = function (coin) {
		console.log("add");
		self.coins.push(coin);
		self.addChild(coin);
	};
	self.removeCoin = function (coin) {
		var index = self.coins.indexOf(coin);
		if (index > -1) {
			self.coins.splice(index, 1);
			coin.destroy();
		}
	};
	self.updateCoinDisplay = function () {
		var gameInstance = self.getGameInstance();
		if (gameInstance) {
			gameInstance.updateCoinDisplay(self.coins.length);
		}
	};
});
var Coin = Container.expand(function () {
	var self = Container.call(this);
	var coinGraphics = self.createAsset('coin', 'Coin Graphics', .5, .5);
	self.init = function (coinLayer) {
		self.x = Math.random() * (2048 - self.width) + self.width / 2;
		self.y = Math.random() * (2732 - self.height) + self.height / 2;
		coinLayer.addCoin(self);
		coinLayer.updateCoinDisplay();
	};
	self.on('down', function () {
		var gameInstance = self.getGameInstance();
		LK.setScore(LK.getScore() + 1);
		gameInstance.updateScoreDisplay();
		gameInstance.coinLayer.removeCoin(self);
		gameInstance.updateCoinDisplay();
	});
});
var Shadow = Container.expand(function () {
	var self = Container.call(this);
	var shadowGraphics = self.createAsset('shadow', 'Shadow Graphics', .5, .5);
	self.follow = function (target) {
		self.x = target.x;
		self.y = target.y + 50;
		var scale = target.scale.x * target.scale.x * 0.7;
		self.scale.x = self.scale.y = scale;
		self.scale.x = self.scale.y = scale;
		self.alpha = .5 / scale;
	};
});
var Aim = Container.expand(function () {
	var self = Container.call(this);
	var aimGraphics = self.createAsset('aim', 'Aim Graphics', .5, .5);
});
var ParticleSplash = Container.expand(function () {
	var self = Container.call(this);
	var particleSplashGraphics = self.createAsset('particleSplash', 'Particle Splash Graphics', .5, .5);
	var randomScale = 0.5 + Math.random() * 0.5;
	self.scale.x = randomScale;
	self.scale.y = randomScale;
	self.directionX = Math.random() * 2 - 1;
	self.directionY = Math.random() * 2 - 1;
	self.animate = function () {
		self.alpha -= 0.01;
		self.x += self.directionX;
		self.y += self.directionY;
		if (self.alpha <= 0) {
			self.destroy();
		}
	};
});
var Snowball = Container.expand(function () {
	var self = Container.call(this);
	var snowballGraphics = self.createAsset('snowball', 'Snowball Graphics', .5, .5);
	self.speed = -5;
	self.speedX = 0;
	self.speedY = 0;
	self.totalDistance = 0;
	self.rotationAjd = (Math.random() - 1) * 0.05;
	self.move = function () {
		self.totalDistance = Math.sqrt(Math.pow(self.startX - self.x, 2) + Math.pow(self.y - self.startY, 2));
		var halfDistance = self.targetTotalDistance / 2;
		var distanceFromHalf = 0;
		if (self.totalDistance < halfDistance) distanceFromHalf = halfDistance - self.totalDistance; else distanceFromHalf = self.totalDistance - halfDistance;
		var percentFromHalf = distanceFromHalf / halfDistance;
		if (percentFromHalf > 1.1) {
			self.shouldBeDestroyed = true;
		} else {
			var scaleAdj = 2 - percentFromHalf * 2;
			self.scale.x = 1 + scaleAdj;
			self.scale.y = 1 + scaleAdj;
			self.rotation += self.rotationAjd;
			self.mayHit = scaleAdj < 0.8;
			self.x += self.speedX;
			self.y += self.speedY;
			if (self.shadow) self.shadow.follow(self);
		}
	};
	self.init = function () {
		self.targetTotalDistance = Math.sqrt(Math.pow(self.targetX - self.x, 2) + Math.pow(self.y - self.targetY, 2));
		self.shadow = new Shadow();
		self.shadow.follow(self);
		LK.stage.addChild(self.shadow);
		LK.stage.addChild(self);
	};
});
var ZombieKid = Container.expand(function () {
	var self = Container.call(this);
	var zombieKidGraphics = self.createAsset('zombieKid', 'Zombie Kid Graphics', .5, 0.8);
	self.speed = Math.random() * 2 + 1;
	self.hasGift = false;
	self.pickedUpGift = null;
	self.findNewTarget = function () {
		var availableGifts = [];
		if (this.parent) {
			availableGifts = this.parent.children.filter(function (child) {
				return child instanceof ChristmasGift && !child.isDestroyed && !child.hasBeenPickedUp;
			});
		}
		if (availableGifts.length > 0) {
			var randomIndex = Math.floor(Math.random() * availableGifts.length);
			this.targetGift = availableGifts[randomIndex];
		}
	};
	self.move = function () {
		if (!self.hasGift) {
			if (self.targetGift) {
				var dx = self.targetGift.x - self.x;
				var dy = self.targetGift.y - self.y;
			}
			var angle = Math.atan2(dy, dx);
			self.x += Math.cos(angle) * self.speed;
			self.y += Math.sin(angle) * self.speed;
			if (self.targetGift && !self.targetGift.isDestroyed && !self.targetGift.hasBeenPickedUp && Math.abs(self.x - self.targetGift.x) < 10 && Math.abs(self.y - self.targetGift.y + 50) < 50) {
				self.hasGift = true;
				self.targetGift.hasBeenPickedUp = true;
				self.targetGift.owner = self;
				self.pickedUpGift = self.targetGift;
				if (self.pickedUpGift.parent) {
					self.pickedUpGift.parent.setChildIndex(self.pickedUpGift, self.pickedUpGift.parent.children.length - 1);
				}
			} else if (!self.targetGift || self.targetGift.isDestroyed || self.targetGift.hasBeenPickedUp) {
				self.findNewTarget();
			}
		} else {
			if (self.hasGift && !self.speedIncreased) {
				self.speed *= 1.5;
				self.speedIncreased = true;
			}
			self.y -= self.speed;
			if (self.pickedUpGift) {
				self.pickedUpGift.x = self.x;
				self.pickedUpGift.y = self.y + 30;
				self.pickedUpGift.hasBeenPickedUp = true;
			}
		}
	};
});
var Santa = Container.expand(function () {
	var self = Container.call(this);
	var santaGraphics = self.createAsset('santa', 'Santa Graphics', .5, .5);
});
var ChristmasGift = Container.expand(function () {
	var self = Container.call(this);
	self.offScreenHandler = function () {
		if (self.y > 2732 || self.x < 0 || self.x > 2048 || self.y < 0) {
			self.flaggedForRemoval = true;
		}
	};
	var giftTypes = ['christmasGift1', 'christmasGift2', 'christmasGift3'];
	var randomType = giftTypes[Math.floor(Math.random() * giftTypes.length)];
	var christmasGiftGraphics = self.createAsset(randomType, 'Christmas Gifts Graphics', 0.5, 1);
	self.x = Math.random() * 1536 + 256;
	self.y = Math.random() * 1532 + 500;
});
var ProgressBar = Container.expand(function () {
	var self = Container.call(this);
	var progressBarGraphics = self.createAsset('progressBar2', 'Progress Bar Graphics', 0.5, 0.5);
	self.updateProgress = function (progress) {
		progressBarGraphics.scale.x = progress;
		self.alpha = Math.max(progress, 0.15);
	};
	self.init = function () {
		self.x = LK.gui.width / 2;
		self.y = LK.gui.height - 25;
		LK.gui.addChild(self);
	};
	self.alpha = 0.45;
	self.maxScale = LK.gui.width / 100;
	self.scale.x = self.maxScale;
	self.height = 45;
	self.init();
});
var snowballUpgrades = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
var baseStrength = 1;
var upgrades = {
	snowballs: 0,
	strength: 0,
	gifts: 0
};
function upgrade(type) {
	console.log("upgrade", type);
}
function pulsate(item, amount, scaleStep) {
	var maxScale = 1 * amount;
	var minScale = 1 / amount;
	var scaleStep = scaleStep || 0.004;
	var growing = true;
	item.scale.x = minScale;
	item.scale.y = minScale;
	LK.on('tick', function () {
		if (growing) {
			item.scale.x += scaleStep;
			item.scale.y += scaleStep;
			if (item.scale.x >= maxScale) growing = false;
		} else {
			item.scale.x -= scaleStep;
			item.scale.y -= scaleStep;
			if (item.scale.x <= minScale) growing = true;
		}
	});
}
;
Container.prototype.getGameInstance = function () {
	var currentParent = this.parent;
	while (currentParent) {
		if (currentParent instanceof Game) {
			return currentParent;
		}
		currentParent = currentParent.parent;
	}
	if (currentParent === LK.stage) {
		return LK.stage.children.find(function (child) {
			return child instanceof Game;
		});
	}
	return LK.stage.children.find(function (child) {
		return child instanceof Game;
	});
};
var currentLevel = 0;
var levels = [{
	numZombieKids: 10,
	coinFrequency: 0.1,
	zombieKidSpeed: 2
}, {
	numZombieKids: 15,
	coinFrequency: 0.15,
	zombieKidSpeed: 2.5
}, {
	numZombieKids: 20,
	coinFrequency: 0.2,
	zombieKidSpeed: 3
}];
var Game = Container.expand(function () {
	var self = Container.call(this);
	LK.setInterval(function () {
		if (Math.random() < 0.90) return;
		var coin = new Coin();
		coin.init(self.coinLayer);
	}, 100);
	self.showUpgradeContainer = function () {
		var upgradeContainer = new UpgradeContainer();
		LK.gui.addChild(upgradeContainer);
	};
	var introScreen = new IntroScreen();
	LK.gui.addChild(introScreen);
	self.progressBar = new ProgressBar();
	self.zombieKids = [];
	self.spawnZombieKids = function () {
		self.christmasGifts = self.christmasGifts || [];
		for (var i = 0; i < self.numZombieKids; i++) {
			var newZombieKid = new ZombieKid();
			newZombieKid.speed = self.zombieKidSpeed;
			newZombieKid.x = Math.random() * (2048 - newZombieKid.width);
			newZombieKid.y = 0;
			self.zombieKids.push(newZombieKid);
			self.addChild(newZombieKid);
		}
	};
	self.startNextWave = function () {
		console.log("Start level", currentLevel);
		self.wallet.visible = true;
		if (currentLevel < levels.length) {
			var level = levels[currentLevel];
			self.numZombieKids = level.numZombieKids;
			self.coinFrequency = level.coinFrequency;
			self.zombieKidSpeed = level.zombieKidSpeed;
			self.spawnZombieKids();
			currentLevel++;
			var waveCounterTxt = new WaveCounterText(currentLevel);
			self.addChild(waveCounterTxt);
			self.waveInProgress = true;
		} else {
			LK.showGameOver();
		}
	};
	var background = self.createAsset('background', 'Full Screen Background', 0, 0);
	background.width = 2048;
	background.height = 2732;
	self.isThrowing = false;
	self.addChildAt(background, 0);
	self.coinLayer = new CoinLayer();
	self.addChild(self.coinLayer);
	var santa = self.addChild(new Santa());
	santa.x = 2048 / 2;
	santa.y = 2732 - santa.height - 2732 / 20;
	self.christmasGifts = self.christmasGifts || [];
	var placedGifts = 0;
	var tries = 0;
	self.placeGift = function () {
		var gift = new ChristmasGift();
		pulsate(gift, 1.03, 0.002);
		var intersects = false;
		for (var j = 0; j < self.christmasGifts.length; j++) {
			if (gift === self.christmasGifts[j]) continue;
			if (Math.abs(gift.x - self.christmasGifts[j].x) < 150 && Math.abs(gift.y - self.christmasGifts[j].y) < 150) intersects = true;
		}
		if (!intersects) {
			self.christmasGifts.push(gift);
			self.addChild(gift);
			placedGifts++;
			this.giftCounterTxt.setText('Gifts: ' + self.christmasGifts.length);
		}
	};
	self.giftCounterTxt = new Text2('Gifts: 10', {
		size: 100,
		fill: "#000000"
	});
	while (placedGifts < 10) {
		tries++;
		if (tries > 1000) break;
		self.placeGift();
	}
	var scoreTxt = new Text2('0', {
		size: 150,
		fill: "#000000"
	});
	var coinCounterTxt = new Text2('0', {
		size: 100,
		fill: "#000000"
	});
	self.wallet = new Wallet();
	self.wallet.init();
	self.wallet.visible = false;
	self.coinLayer = new CoinLayer();
	self.addChild(self.coinLayer);
	coinCounterTxt.x = 2048 - coinCounterTxt.width / 2;
	coinCounterTxt.y = 100;
	coinCounterTxt.anchor.set(0.5, 0);
	LK.gui.addChild(coinCounterTxt);
	self.updateCoinDisplay = function (coinCount) {
		coinCounterTxt.setText('' + (coinCount ? coinCount.toString() : '0'));
	};
	self.updateCoinDisplay();
	self.giftCounterTxt.anchor.set(.5, 0);
	self.giftCounterTxt.y = 1710;
	LK.gui.topCenter.addChild(self.giftCounterTxt);
	self.giftCounterTxt.setText('Gifts left: ' + self.christmasGifts.length);
	scoreTxt.anchor.set(.5, 0);
	LK.gui.topCenter.addChild(scoreTxt);
	self.updateScoreDisplay = function () {
		scoreTxt.setText(LK.getScore().toString());
	};
	self.updateScoreDisplay();
	self.snowballs = [];
	var touchStartTime = 0;
	stage.on('down', function (obj) {
		touchStartTime = LK.ticks;
		isThrowing = true;
		var event = obj.event;
		var pos = event.getLocalPosition(self);
		santa.baseRotation = Math.atan2(pos.y - santa.y, pos.x - santa.x) + Math.PI * 0.6;
		self.aimPosition = pos;
		var aim = new Aim();
		self.currentAim = aim;
		aim.x = pos.x;
		aim.y = pos.y;
		var progress = 0;
		aim.scale.x = aim.scale.y = 0.5 + progress * 0.5;
		self.addChild(aim);
		aim.tweenToAlpha = function (targetAlpha, duration) {
			var step = (1 - targetAlpha) / (duration * 60);
			var fadeInterval = LK.setInterval(function () {
				aim.alpha -= step;
				if (aim.alpha <= targetAlpha) {
					LK.clearInterval(fadeInterval);
					aim.destroy();
				}
			}, 1000 / 60);
		};
		aim.tweenToAlpha(0, 3);
	});
	stage.on('up', function (obj) {
		if (self.aim) {
			self.aim.destroy();
			self.aim = null;
		}
		self.progressBar.updateProgress(0);
		santa.rotation = santa.baseRotation;
		isThrowing = false;
		if (self.snowballs.length < 3 && self.aimPosition) {
			var newSnowball = new Snowball(self.currentAim);
			newSnowball.x = santa.x + 120;
			;
			newSnowball.y = santa.y;
			newSnowball.startX = santa.x + 120;
			newSnowball.startY = santa.y;
			newSnowball.targetX = self.aimPosition.x;
			newSnowball.targetY = self.aimPosition.y;
			newSnowball.init();
			var dx = newSnowball.targetX - newSnowball.x;
			var dy = newSnowball.targetY - newSnowball.y;
			var distance = Math.sqrt(dx * dx + dy * dy);
			var throwSpeed = 10;
			var touchDuration = LK.ticks - touchStartTime;
			var speedMultiplier = Math.min(touchDuration / 30, 10) * throwSpeed;
			newSnowball.speedMultiplier = speedMultiplier;
			newSnowball.speedX = -dx / distance * newSnowball.speed * speedMultiplier;
			newSnowball.speedY = -Math.abs(dy / distance * newSnowball.speed) * speedMultiplier;
			self.snowballs.push(newSnowball);
			self.aimPosition = null;
		}
		self.currentAim = null;
	});
	LK.on('tick', function () {
		var zombieKids = self.zombieKids;
		if (touchStartTime > 0 && isThrowing) {
			var progress = Math.min((LK.ticks - touchStartTime) / 30, 1);
			self.progressBar.updateProgress(progress);
			santa.rotation = santa.baseRotation + progress * Math.PI * 2 / 10;
			if (self.aim) {
				self.aim.scale.x = self.aim.scale.y = 0.5 + progressBarGraphics.scale.x * 0.5;
			}
			if (self.currentAim) {
				self.currentAim.scale.x = 0.2 + progress;
				self.currentAim.scale.y = 0.2 + progress;
			}
		}
		for (var a = self.snowballs.length - 1; a >= 0; a--) {
			if (self.snowballs[a]) {
				snowballs[a].move();
				for (var b = self.zombieKids.length - 1; b >= 0; b--) {
					if (zombieKids[b] && snowballs[a] && snowballs[a].intersects(zombieKids[b]) && snowballs[a].mayHit) {
						LK.setScore(LK.getScore() + 1);
						self.updateScoreDisplay();
						for (var i = 0; i < 10; i++) {
							var particleSplash = new ParticleSplash();
							particleSplash.x = snowballs[a].x;
							particleSplash.y = snowballs[a].y;
							particleSplash.directionX *= snowballs[a].speedY;
							particleSplash.directionY *= snowballs[a].speedY;
							self.addChild(particleSplash);
						}
						if (zombieKids[b].hasGift) {
							var droppedGift = zombieKids[b].pickedUpGift;
							droppedGift.x = zombieKids[b].x;
							droppedGift.y = zombieKids[b].y;
							droppedGift.hasBeenDropped = true;
							droppedGift.hasBeenPickedUp = false;
						}
						zombieKids[b].destroy();
						zombieKids.splice(b, 1);
						if (self.snowballs[a].aim) self.snowballs[a].aim.destroy();
						if (snowballs[a].shadow) snowballs[a].shadow.destroy();
						snowballs[a].destroy();
						snowballs[a].shadow.destroy();
						snowballs.splice(a, 1);
						break;
					}
				}
				if (snowballs[a] && (snowballs[a].y < -50 || snowballs[a].shouldBeDestroyed)) {
					snowballs[a].destroy();
					snowballs[a].shadow.destroy();
					snowballs.splice(a, 1);
				}
			}
		}
		if (self.zombieKids.length === 0 && self.waveInProgress && currentLevel > 0) {
			self.waveInProgress = false;
			LK.setTimeout(function () {
				self.showUpgradeContainer();
			}, 1000);
		}
		for (var b = self.zombieKids.length - 1; b >= 0; b--) {
			if (zombieKids[b]) {
				zombieKids[b].move();
			}
		}
		for (var c = self.children.length - 1; c >= 0; c--) {
			if (self.children[c] instanceof ParticleSplash) {
				self.children[c].animate();
			}
		}
		for (var j = 0; j < self.christmasGifts.length; j++) {
			self.christmasGifts[j].offScreenHandler();
			if (self.christmasGifts[j].flaggedForRemoval) {
				self.christmasGifts[j].owner.hasGift = false;
				self.christmasGifts[j].owner.targetGift = false;
				self.christmasGifts[j].destroy();
				self.christmasGifts.splice(j, 1);
				self.giftCounterTxt.setText('Gifts left: ' + self.christmasGifts.length);
				if (self.christmasGifts.length === 0) LK.showGameOver();
			}
		}
	});
});

===================================================================
--- original.js
+++ change.js
@@ -644,9 +644,9 @@
 				self.currentAim.scale.y = 0.2 + progress;
 			}
 		}
 		for (var a = self.snowballs.length - 1; a >= 0; a--) {
-			if (snowballs[a]) {
+			if (self.snowballs[a]) {
 				snowballs[a].move();
 				for (var b = self.zombieKids.length - 1; b >= 0; b--) {
 					if (zombieKids[b] && snowballs[a] && snowballs[a].intersects(zombieKids[b]) && snowballs[a].mayHit) {
 						LK.setScore(LK.getScore() + 1);