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

/**** 
* Classes
****/ 
// Bullet class
var Bullet = Container.expand(function () {
	var self = Container.call(this);
	var bulletSprite = self.attachAsset('bullet', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Velocity components
	self.vx = 0;
	self.vy = -22;
	// Set direction and speed
	self.setDirection = function (dx, dy, speed) {
		var len = Math.sqrt(dx * dx + dy * dy);
		if (len === 0) {
			self.vx = 0;
			self.vy = -Math.abs(speed);
		} else {
			self.vx = dx / len * speed;
			self.vy = dy / len * speed;
		}
		// Rotate bullet to face direction
		self.rotation = Math.atan2(self.vy, self.vx) + Math.PI / 2;
	};
	// Default: straight up
	self.setDirection(0, -1, 22);
	self.update = function () {
		self.x += self.vx;
		self.y += self.vy;
	};
	return self;
});
// Powerup class
var Powerup = Container.expand(function () {
	var self = Container.call(this);
	var powerupSprite = self.attachAsset('powerup', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.speed = 7;
	self.update = function () {
		self.y += self.speed;
	};
	return self;
});
// Survivor class
var Survivor = Container.expand(function () {
	var self = Container.call(this);
	var survivorSprite = self.attachAsset('survivor', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// For powerup effect
	self.isPowered = false;
	self.powerTimer = 0;
	// For future: add more survivor logic here
	return self;
});
// Zombie class
var Zombie = Container.expand(function () {
	var self = Container.call(this);
	var zombieSprite = self.attachAsset('zombie', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	// Movement speed (pixels per frame) -- REDUCED for slower zombies
	self.speed = 1.2 + Math.random() * 0.7;
	// Sway amplitude and frequency for zigzag (not used anymore, but kept for possible future use)
	self.swayAmp = 60 + Math.random() * 80;
	self.swayFreq = 0.005 + Math.random() * 0.003;
	self.baseX = 0;
	self.t = 0;
	// For tracking last position for offscreen detection
	self.lastY = undefined;
	// For tracking intersection with bullets
	self.lastIntersecting = false;
	// For tracking intersection with survivor
	self.lastTouchSurvivor = false;
	// For powerup drop
	self.hasDroppedPowerup = false;
	// New: spawnType and movement toward play area
	self.spawnType = "top"; // "top", "left", "right"
	self.targetX = 2048 / 2;
	self.targetY = 2732 - 400; // play area center-ish
	self.initSpawn = function (type, x, y, targetX, targetY) {
		self.spawnType = type;
		self.x = x;
		self.y = y;
		self.targetX = targetX;
		self.targetY = targetY;
		self.baseX = x;
		// Calculate direction vector for left/right spawn
		if (type === "left" || type === "right") {
			var dx = targetX - x;
			var dy = targetY - y;
			var len = Math.sqrt(dx * dx + dy * dy);
			self.dirX = dx / len;
			self.dirY = dy / len;
		}
	};
	self.update = function () {
		self.t += 1;
		// Always move directly toward survivor
		if (typeof survivor !== "undefined") {
			var dx = survivor.x - self.x;
			var dy = survivor.y - self.y;
			var dist = Math.sqrt(dx * dx + dy * dy);
			if (dist > 0) {
				self.x += dx / dist * self.speed;
				self.y += dy / dist * self.speed;
			}
			// Rotate zombie to face survivor
			self.rotation = Math.atan2(dy, dx);
		}
	};
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x181818
});

/**** 
* Game Code
****/ 
// Music (not played in MVP as per instructions, but asset is here for future)
// Sound for zombie hit
// Sound for powerup
// Sound for shooting
// Powerup asset: a magenta ellipse
// Bullet asset: a yellow box
// Zombie asset: a green ellipse
// Survivor (player) asset: a blue box
// Survivor instance
var survivor = new Survivor();
game.addChild(survivor);
// Place survivor in the middle of the screen
survivor.x = 2048 / 2;
survivor.y = 2732 / 2;
// Arrays for game objects
var zombies = [];
var bullets = [];
var powerups = [];
// Score display
var scoreTxt = new Text2('0', {
	size: 120,
	fill: "#fff"
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
// Health bar variables and UI
var survivorMaxHealth = 5;
var survivorHealth = survivorMaxHealth;
var healthBarWidth = 400;
var healthBarHeight = 36;
var healthBarBg = LK.getAsset('healthbar_bg', {
	width: healthBarWidth,
	height: healthBarHeight,
	color: 0x333333,
	shape: 'box',
	anchorX: 0.5,
	anchorY: 0
});
var healthBarFg = LK.getAsset('healthbar_fg', {
	width: healthBarWidth,
	height: healthBarHeight,
	color: 0x4de14d,
	shape: 'box',
	anchorX: 0.5,
	anchorY: 0
});
healthBarBg.y = 120;
healthBarFg.y = 120;
healthBarBg.x = 2048 / 2;
healthBarFg.x = 2048 / 2;
LK.gui.top.addChild(healthBarBg);
LK.gui.top.addChild(healthBarFg);
// Powerup timer display
var powerupTxt = new Text2('', {
	size: 70,
	fill: 0xFF3FD6
});
powerupTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(powerupTxt);
powerupTxt.y = 170;
// Game state
var dragNode = null;
var canShoot = true;
var shootCooldown = 0;
var shootInterval = 12; // frames between shots
var zombieSpawnTimer = 0;
var zombieSpawnInterval = 60; // frames between spawns, will decrease
var zombieSpeedIncrease = 0;
var powerupActive = false;
var powerupTimer = 0;
var powerupDuration = 360; // frames (6 seconds)
var lastGameOver = false;
// Helper: spawn a zombie
function spawnZombie() {
	var z = new Zombie();
	// Randomly choose spawn edge: 0=top, 1=left, 2=right
	var edge = Math.floor(Math.random() * 3);
	var margin = 120;
	var spawnType, zx, zy, tx, ty;
	tx = 2048 / 2;
	ty = 2732 - 400;
	if (edge === 0) {
		// Top
		spawnType = "top";
		zx = margin + Math.random() * (2048 - 2 * margin);
		zy = -100;
	} else if (edge === 1) {
		// Left
		spawnType = "left";
		zx = -100;
		zy = 300 + Math.random() * (2732 - 800);
	} else {
		// Right
		spawnType = "right";
		zx = 2048 + 100;
		zy = 300 + Math.random() * (2732 - 800);
	}
	z.initSpawn(spawnType, zx, zy, tx, ty);
	// Increase speed as game progresses
	z.speed += zombieSpeedIncrease;
	zombies.push(z);
	game.addChild(z);
}
// Helper: spawn a powerup at (x, y)
function spawnPowerup(x, y) {
	var p = new Powerup();
	p.x = x;
	p.y = y;
	powerups.push(p);
	game.addChild(p);
}
// Helper: shoot a bullet
function shootBullet(targetX, targetY) {
	if (!canShoot) return;
	canShoot = false;
	shootCooldown = 0;
	var b = new Bullet();
	b.x = survivor.x;
	b.y = survivor.y - 80;
	// If no target provided, shoot straight up
	if (typeof targetX === "number" && typeof targetY === "number") {
		var dx = targetX - survivor.x;
		var dy = targetY - (survivor.y - 80);
		b.setDirection(dx, dy, 22);
	} else {
		b.setDirection(0, -1, 22);
	}
	bullets.push(b);
	game.addChild(b);
	LK.getSound('shoot').play();
}
// Dragging logic
// (player movement removed)
function handleMove(x, y, obj) {
	// Always rotate survivor to face the pointer (x, y)
	var dx = x - survivor.x;
	var dy = y - survivor.y;
	// If pointer is on the left half and in the vertical middle, rotate survivor 180 degrees
	if (x < 2048 / 2 && y > 2732 / 4 && y < 2732 * 3 / 4) {
		survivor.rotation = Math.atan2(dy, dx) + Math.PI;
	} else {
		survivor.rotation = Math.atan2(dy, dx);
	}
}
game.move = handleMove;
// Tap to shoot logic
game.tap = function (x, y, obj) {
	// Allow tap to shoot anywhere, even if dragging
	shootBullet(x, y);
};
// For touch devices, simulate tap on quick down/up
var lastDownTime = 0;
game.down = function (x, y, obj) {
	lastDownTime = Date.now();
};
game.up = function (x, y, obj) {
	// If quick tap, treat as tap to shoot
	if (Date.now() - lastDownTime < 250) {
		shootBullet(x, y);
	}
};
// Main update loop
game.update = function () {
	// Handle survivor powerup timer
	if (powerupActive) {
		powerupTimer--;
		if (powerupTimer <= 0) {
			powerupActive = false;
			survivor.isPowered = false;
			powerupTxt.setText('');
			// Visual: scale back to normal
			tween(survivor, {
				scaleX: 1,
				scaleY: 1
			}, {
				duration: 200,
				easing: tween.easeOut
			});
		} else {
			powerupTxt.setText('POWER! ' + Math.ceil(powerupTimer / 60));
		}
	}
	// Shooting cooldown
	if (!canShoot) {
		shootCooldown++;
		if (shootCooldown >= (powerupActive ? 4 : shootInterval)) {
			canShoot = true;
		}
	}
	// Spawn zombies
	zombieSpawnTimer++;
	if (zombieSpawnTimer >= zombieSpawnInterval) {
		spawnZombie();
		zombieSpawnTimer = 0;
		// Increase difficulty over time
		if (zombieSpawnInterval > 24) zombieSpawnInterval -= 1;
		zombieSpeedIncrease += 0.01;
	}
	// Update bullets
	for (var i = bullets.length - 1; i >= 0; i--) {
		var b = bullets[i];
		b.update();
		// Remove if offscreen
		if (b.y < -100) {
			b.destroy();
			bullets.splice(i, 1);
			continue;
		}
		// Check collision with zombies
		for (var j = zombies.length - 1; j >= 0; j--) {
			var z = zombies[j];
			if (b.intersects(z)) {
				// Hit!
				LK.getSound('zombiehit').play();
				// Score
				LK.setScore(LK.getScore() + 1);
				scoreTxt.setText(LK.getScore());
				// Powerup drop chance
				if (!z.hasDroppedPowerup && Math.random() < 0.08) {
					spawnPowerup(z.x, z.y);
					z.hasDroppedPowerup = true;
				}
				// Visual: flash zombie
				LK.effects.flashObject(z, 0xffffff, 200);
				// Remove both
				z.destroy();
				zombies.splice(j, 1);
				b.destroy();
				bullets.splice(i, 1);
				break;
			}
		}
	}
	// Update zombies
	for (var i = zombies.length - 1; i >= 0; i--) {
		var z = zombies[i];
		z.update();
		// Remove if offscreen (bottom)
		if (z.y > 2732 + 100) {
			z.destroy();
			zombies.splice(i, 1);
			continue;
		}
		// Check collision with survivor
		if (z.intersects(survivor)) {
			// Only damage once per collision
			if (!z.lastTouchSurvivor) {
				survivorHealth--;
				// Animate health bar
				var healthFrac = Math.max(0, survivorHealth) / survivorMaxHealth;
				healthBarFg.width = healthBarWidth * healthFrac;
				LK.effects.flashObject(survivor, 0xff0000, 200);
				if (survivorHealth <= 0 && !lastGameOver) {
					LK.effects.flashScreen(0xff0000, 1000);
					lastGameOver = true;
					LK.showGameOver();
					return;
				}
			}
			z.lastTouchSurvivor = true;
		} else {
			z.lastTouchSurvivor = false;
		}
	}
	// Update powerups
	for (var i = powerups.length - 1; i >= 0; i--) {
		var p = powerups[i];
		p.update();
		// Remove if offscreen
		if (p.y > 2732 + 100) {
			p.destroy();
			powerups.splice(i, 1);
			continue;
		}
		// Check collision with survivor
		if (p.intersects(survivor)) {
			LK.getSound('powerup').play();
			// Activate powerup: rapid fire
			powerupActive = true;
			powerupTimer = powerupDuration;
			survivor.isPowered = true;
			// Visual: scale up
			tween(survivor, {
				scaleX: 1.3,
				scaleY: 1.3
			}, {
				duration: 200,
				easing: tween.easeOut
			});
			powerupTxt.setText('POWER! ' + Math.ceil(powerupTimer / 60));
			p.destroy();
			powerups.splice(i, 1);
			continue;
		}
	}
};
// Reset game state on restart
LK.on('gameStart', function () {
	// Remove all zombies, bullets, powerups
	for (var i = 0; i < zombies.length; i++) zombies[i].destroy();
	for (var i = 0; i < bullets.length; i++) bullets[i].destroy();
	for (var i = 0; i < powerups.length; i++) powerups[i].destroy();
	zombies = [];
	bullets = [];
	powerups = [];
	// Reset survivor
	survivor.x = 2048 / 2;
	survivor.y = 2732 / 2;
	survivor.isPowered = false;
	survivor.scaleX = 1;
	survivor.scaleY = 1;
	survivorHealth = survivorMaxHealth;
	healthBarFg.width = healthBarWidth;
	// Reset timers and state
	canShoot = true;
	shootCooldown = 0;
	zombieSpawnTimer = 0;
	zombieSpawnInterval = 60;
	zombieSpeedIncrease = 0;
	powerupActive = false;
	powerupTimer = 0;
	powerupTxt.setText('');
	lastGameOver = false;
	LK.setScore(0);
	scoreTxt.setText('0');
});