/**** 
* Plugins
****/ 
var tween = LK.import("@upit/tween.v1");

/**** 
* Classes
****/ 
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletGraphics = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 8;
	self.direction = {
		x: 0,
		y: -1
	};
	self.update = function () {
		self.x += self.direction.x * self.speed;
		self.y += self.direction.y * self.speed;
	};
	return self;
});
var HealthPack = Container.expand(function () {
	var self = Container.call(this);
	var healthGraphics = self.attachAsset('healthPack', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.healAmount = 25;
	return self;
});
var Player = Container.expand(function () {
	var self = Container.call(this);
	var playerGraphics = self.attachAsset('player', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.health = 100;
	self.maxHealth = 100;
	self.lastShotTime = 0;
	self.shootCooldown = 200; // milliseconds
	self.facing = {
		x: 0,
		y: -1
	}; // initially facing up
	return self;
});
var WeaponUpgrade = Container.expand(function () {
	var self = Container.call(this);
	var weaponGraphics = self.attachAsset('weaponUpgrade', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	return self;
});
var Zombie = Container.expand(function () {
	var self = Container.call(this);
	var zombieGraphics = self.attachAsset('zombie', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 1;
	self.health = 1;
	self.update = function () {
		if (player) {
			var dx = player.x - self.x;
			var dy = player.y - self.y;
			var distance = Math.sqrt(dx * dx + dy * dy);
			if (distance > 0) {
				self.x += dx / distance * self.speed;
				self.y += dy / distance * self.speed;
			}
		}
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x2d2d2d
});

/**** 
* Game Code
****/ 
var player = null;
var zombies = [];
var bullets = [];
var healthPacks = [];
var weaponUpgrades = [];
var gameTime = 0;
var zombieSpawnRate = 120; // frames between spawns
var lastZombieSpawn = 0;
var lastPickupSpawn = 0;
var pickupSpawnRate = 300; // frames between pickups
var dragNode = null;
var lastPlayerPosition = {
	x: 0,
	y: 0
};
// UI Elements
var healthBar = LK.getAsset('healthPack', {
	anchorX: 0,
	anchorY: 0,
	scaleX: 5,
	scaleY: 0.5
});
var scoreTxt = new Text2('Score: 0', {
	size: 60,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
var healthTxt = new Text2('Health: 100', {
	size: 50,
	fill: 0xFFFFFF
});
healthTxt.anchor.set(0, 0);
LK.gui.top.addChild(scoreTxt);
LK.gui.topRight.addChild(healthTxt);
LK.gui.topRight.addChild(healthBar);
healthBar.x = -200;
healthBar.y = 60;
// Initialize player
player = game.addChild(new Player());
player.x = 2048 / 2;
player.y = 2732 / 2;
lastPlayerPosition.x = player.x;
lastPlayerPosition.y = player.y;
function spawnZombie() {
	var zombie = new Zombie();
	var side = Math.floor(Math.random() * 4);
	// Spawn from edges
	switch (side) {
		case 0:
			// top
			zombie.x = Math.random() * 2048;
			zombie.y = -30;
			break;
		case 1:
			// right
			zombie.x = 2048 + 30;
			zombie.y = Math.random() * 2732;
			break;
		case 2:
			// bottom
			zombie.x = Math.random() * 2048;
			zombie.y = 2732 + 30;
			break;
		case 3:
			// left
			zombie.x = -30;
			zombie.y = Math.random() * 2732;
			break;
	}
	// Increase speed over time
	zombie.speed = 1 + gameTime / 3600 * 0.5;
	zombies.push(zombie);
	game.addChild(zombie);
}
function spawnHealthPack() {
	var healthPack = new HealthPack();
	healthPack.x = Math.random() * (2048 - 100) + 50;
	healthPack.y = Math.random() * (2732 - 100) + 50;
	healthPacks.push(healthPack);
	game.addChild(healthPack);
}
function spawnWeaponUpgrade() {
	var weaponUpgrade = new WeaponUpgrade();
	weaponUpgrade.x = Math.random() * (2048 - 100) + 50;
	weaponUpgrade.y = Math.random() * (2732 - 100) + 50;
	weaponUpgrades.push(weaponUpgrade);
	game.addChild(weaponUpgrade);
}
function shootBullet() {
	if (Date.now() - player.lastShotTime > player.shootCooldown) {
		var bullet = new Bullet();
		bullet.x = player.x;
		bullet.y = player.y;
		bullet.direction.x = player.facing.x;
		bullet.direction.y = player.facing.y;
		bullets.push(bullet);
		game.addChild(bullet);
		player.lastShotTime = Date.now();
		LK.getSound('shoot').play();
	}
}
function updatePlayerFacing() {
	var dx = player.x - lastPlayerPosition.x;
	var dy = player.y - lastPlayerPosition.y;
	var distance = Math.sqrt(dx * dx + dy * dy);
	if (distance > 2) {
		player.facing.x = dx / distance;
		player.facing.y = dy / distance;
	}
	lastPlayerPosition.x = player.x;
	lastPlayerPosition.y = player.y;
}
game.down = function (x, y, obj) {
	dragNode = player;
	player.x = x;
	player.y = y;
};
game.move = function (x, y, obj) {
	if (dragNode) {
		dragNode.x = x;
		dragNode.y = y;
	}
};
game.up = function (x, y, obj) {
	dragNode = null;
};
game.update = function () {
	gameTime++;
	// Update player facing direction
	updatePlayerFacing();
	// Auto shoot
	shootBullet();
	// Spawn zombies
	if (gameTime - lastZombieSpawn > zombieSpawnRate) {
		spawnZombie();
		lastZombieSpawn = gameTime;
		// Increase spawn rate over time
		zombieSpawnRate = Math.max(30, 120 - Math.floor(gameTime / 600));
	}
	// Spawn pickups
	if (gameTime - lastPickupSpawn > pickupSpawnRate) {
		if (Math.random() > 0.5) {
			spawnHealthPack();
		} else {
			spawnWeaponUpgrade();
		}
		lastPickupSpawn = gameTime;
	}
	// Update bullets
	for (var i = bullets.length - 1; i >= 0; i--) {
		var bullet = bullets[i];
		// Remove off-screen bullets
		if (bullet.x < -50 || bullet.x > 2098 || bullet.y < -50 || bullet.y > 2782) {
			bullet.destroy();
			bullets.splice(i, 1);
			continue;
		}
		// Check bullet-zombie collisions
		for (var j = zombies.length - 1; j >= 0; j--) {
			var zombie = zombies[j];
			if (bullet.intersects(zombie)) {
				LK.setScore(LK.getScore() + 10);
				scoreTxt.setText('Score: ' + LK.getScore());
				LK.getSound('zombieHit').play();
				bullet.destroy();
				bullets.splice(i, 1);
				zombie.destroy();
				zombies.splice(j, 1);
				break;
			}
		}
	}
	// Update zombies and check player collision
	for (var i = zombies.length - 1; i >= 0; i--) {
		var zombie = zombies[i];
		if (zombie.intersects(player)) {
			player.health -= 2;
			LK.getSound('damage').play();
			LK.effects.flashObject(player, 0xff0000, 200);
			if (player.health <= 0) {
				LK.showGameOver();
				return;
			}
			healthTxt.setText('Health: ' + player.health);
			healthBar.scaleX = player.health / player.maxHealth * 5;
		}
	}
	// Check health pack collection
	for (var i = healthPacks.length - 1; i >= 0; i--) {
		var healthPack = healthPacks[i];
		if (player.intersects(healthPack)) {
			player.health = Math.min(player.maxHealth, player.health + healthPack.healAmount);
			healthTxt.setText('Health: ' + player.health);
			healthBar.scaleX = player.health / player.maxHealth * 5;
			LK.getSound('pickup').play();
			healthPack.destroy();
			healthPacks.splice(i, 1);
		}
	}
	// Check weapon upgrade collection
	for (var i = weaponUpgrades.length - 1; i >= 0; i--) {
		var weaponUpgrade = weaponUpgrades[i];
		if (player.intersects(weaponUpgrade)) {
			player.shootCooldown = Math.max(50, player.shootCooldown - 20);
			LK.getSound('pickup').play();
			weaponUpgrade.destroy();
			weaponUpgrades.splice(i, 1);
		}
	}
	// Increase score over time
	if (gameTime % 60 === 0) {
		LK.setScore(LK.getScore() + 1);
		scoreTxt.setText('Score: ' + LK.getScore());
	}
};