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

/**** 
* Classes
****/ 
var Apple = Container.expand(function () {
	var self = Container.call(this);
	var appleGraphics = self.attachAsset('apple', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	self.spawn = function () {
		var gridSize = 40;
		var padding = 60;
		var maxX = Math.floor((2048 - padding * 2) / gridSize);
		var maxY = Math.floor((2732 - padding * 2) / gridSize);
		self.x = padding + Math.floor(Math.random() * maxX) * gridSize + gridSize / 2;
		self.y = padding + Math.floor(Math.random() * maxY) * gridSize + gridSize / 2;
	};
	return self;
});
var SnakeHead = Container.expand(function () {
	var self = Container.call(this);
	var headGraphics = self.attachAsset('snakeHead', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	return self;
});
var SnakeSegment = Container.expand(function () {
	var self = Container.call(this);
	var segmentGraphics = self.attachAsset('snakeSegment', {
		anchorX: 0.5,
		anchorY: 0.5
	});
	return self;
});

/**** 
* Initialize Game
****/ 
var game = new LK.Game({
	backgroundColor: 0x1B5E20
});

/**** 
* Game Code
****/ 
var gridSize = 40;
var snake = [];
var snakeDirection = {
	x: 1,
	y: 0
};
var nextDirection = {
	x: 1,
	y: 0
};
var apple = null;
var gameSpeed = 8;
var moveCounter = 0;
var isGameRunning = true;
// Create score display
var scoreTxt = new Text2('Score: 0', {
	size: 80,
	fill: 0xFFFFFF
});
scoreTxt.anchor.set(0.5, 0);
LK.gui.top.addChild(scoreTxt);
// Initialize snake with 3 segments
function initializeSnake() {
	snake = [];
	var startX = 1024;
	var startY = 1366;
	// Create head
	var head = game.addChild(new SnakeHead());
	head.x = startX;
	head.y = startY;
	snake.push(head);
	// Create initial body segments
	for (var i = 1; i < 3; i++) {
		var segment = game.addChild(new SnakeSegment());
		segment.x = startX - i * gridSize;
		segment.y = startY;
		snake.push(segment);
	}
}
// Create apple
function createApple() {
	if (apple) {
		apple.destroy();
	}
	apple = game.addChild(new Apple());
	apple.spawn();
	// Make sure apple doesn't spawn on snake
	var appleOnSnake = true;
	var attempts = 0;
	while (appleOnSnake && attempts < 50) {
		appleOnSnake = false;
		for (var i = 0; i < snake.length; i++) {
			if (Math.abs(apple.x - snake[i].x) < gridSize && Math.abs(apple.y - snake[i].y) < gridSize) {
				appleOnSnake = true;
				apple.spawn();
				break;
			}
		}
		attempts++;
	}
}
// Move snake
function moveSnake() {
	if (!isGameRunning) return;
	snakeDirection.x = nextDirection.x;
	snakeDirection.y = nextDirection.y;
	var head = snake[0];
	var newX = head.x + snakeDirection.x * gridSize;
	var newY = head.y + snakeDirection.y * gridSize;
	// Check wall collisions
	if (newX < 20 || newX > 2028 || newY < 20 || newY > 2712) {
		gameOver();
		return;
	}
	// Check self collision
	for (var i = 1; i < snake.length; i++) {
		if (Math.abs(newX - snake[i].x) < gridSize && Math.abs(newY - snake[i].y) < gridSize) {
			gameOver();
			return;
		}
	}
	// Check apple collision
	var ateApple = false;
	if (apple && Math.abs(newX - apple.x) < gridSize && Math.abs(newY - apple.y) < gridSize) {
		ateApple = true;
		LK.setScore(LK.getScore() + 1);
		scoreTxt.setText('Score: ' + LK.getScore());
		LK.getSound('eat').play();
		createApple();
	}
	// Move all segments
	if (!ateApple) {
		// Remove tail if not growing
		var tail = snake.pop();
		tail.destroy();
	}
	// Add new head
	var newHead = game.addChild(new SnakeHead());
	newHead.x = newX;
	newHead.y = newY;
	snake.unshift(newHead);
	// Convert old head to body segment
	if (snake.length > 1) {
		var oldHead = snake[1];
		var newSegment = game.addChild(new SnakeSegment());
		newSegment.x = oldHead.x;
		newSegment.y = oldHead.y;
		snake[1] = newSegment;
		oldHead.destroy();
	}
}
function gameOver() {
	isGameRunning = false;
	LK.showGameOver();
}
// Touch controls
var touchStartX = 0;
var touchStartY = 0;
var minSwipeDistance = 50;
game.down = function (x, y, obj) {
	touchStartX = x;
	touchStartY = y;
};
game.up = function (x, y, obj) {
	if (!isGameRunning) return;
	var deltaX = x - touchStartX;
	var deltaY = y - touchStartY;
	var distance = Math.sqrt(deltaX * deltaX + deltaY * deltaY);
	if (distance < minSwipeDistance) return;
	// Determine swipe direction
	if (Math.abs(deltaX) > Math.abs(deltaY)) {
		// Horizontal swipe
		if (deltaX > 0 && snakeDirection.x === 0) {
			// Swipe right
			nextDirection = {
				x: 1,
				y: 0
			};
		} else if (deltaX < 0 && snakeDirection.x === 0) {
			// Swipe left
			nextDirection = {
				x: -1,
				y: 0
			};
		}
	} else {
		// Vertical swipe
		if (deltaY > 0 && snakeDirection.y === 0) {
			// Swipe down
			nextDirection = {
				x: 0,
				y: 1
			};
		} else if (deltaY < 0 && snakeDirection.y === 0) {
			// Swipe up
			nextDirection = {
				x: 0,
				y: -1
			};
		}
	}
};
// Initialize game
initializeSnake();
createApple();
// Game update loop
game.update = function () {
	if (!isGameRunning) return;
	moveCounter++;
	if (moveCounter >= gameSpeed) {
		moveCounter = 0;
		moveSnake();
	}
};