/****
* Classes
****/
// Snake segment class
var SnakeSegment = Container.expand(function () {
  var self = Container.call(this);
  var segmentGraphic = self.createAsset('snakeSegment', 'Snake Segment', 0.5, 0.5);
});
// Food class
var Food = Container.expand(function () {
  var self = Container.call(this);
  var foodGraphic = self.createAsset('food', 'Food', 0.5, 0.5);
  self.x = Math.random() * (2048 - foodGraphic.width) + foodGraphic.width / 2;
  self.y = Math.random() * (2732 - foodGraphic.height) + foodGraphic.height / 2;
});

/****
* Initialize Game
****/
var game = new LK.Game({
  backgroundColor: 0x000000 // Init game with black background
});

/****
* Game Code
****/
// Game variables
var snake = [];
var food;
var direction = {
  x: 0,
  y: 0
};
var nextDirection = {
  x: 0,
  y: 0
};
var snakeSpeed = 5;
var updateInterval = 1000 / 60;
var lastUpdateTime = 0;
var isGameOver = false;
// Initialize snake
function initSnake() {
  var initialLength = 5;
  for (var i = 0; i < initialLength; i++) {
    var segment = new SnakeSegment();
    segment.x = 1024;
    segment.y = 1366 + i * segment.height;
    snake.push(segment);
    game.addChild(segment);
  }
  direction = {
    x: 0,
    y: -1
  };
}
// Initialize food
function initFood() {
  food = new Food();
  game.addChild(food);
}
// Check collision with food
function checkFoodCollision() {
  var head = snake[0];
  if (head.intersects(food)) {
    food.destroy();
    addSnakeSegment();
    initFood();
  }
}
// Add new segment to snake
function addSnakeSegment() {
  var tail = snake[snake.length - 1];
  var newSegment = new SnakeSegment();
  newSegment.x = tail.x;
  newSegment.y = tail.y;
  snake.push(newSegment);
  game.addChild(newSegment);
}
// Check self collision
function checkSelfCollision() {
  var head = snake[0];
  for (var i = 1; i < snake.length; i++) {
    if (head.intersects(snake[i])) {
      isGameOver = true;
      break;
    }
  }
}
// Update snake position
function updateSnakePosition() {
  var head = snake[0];
  var newHead = new SnakeSegment();
  newHead.x = head.x + direction.x * head.width;
  newHead.y = head.y + direction.y * head.height;
  snake.unshift(newHead);
  game.addChild(newHead);
  var oldTail = snake.pop();
  oldTail.destroy();
}
// Handle touch input for direction change
function handleTouchInput(obj) {
  var touchPos = obj.event.getLocalPosition(game);
  var head = snake[0];
  var diffX = touchPos.x - head.x;
  var diffY = touchPos.y - head.y;
  if (Math.abs(diffX) > Math.abs(diffY)) {
    nextDirection = {
      x: diffX > 0 ? 1 : -1,
      y: 0
    };
  } else {
    nextDirection = {
      x: 0,
      y: diffY > 0 ? 1 : -1
    };
  }
}
// Game tick update
LK.on('tick', function () {
  if (isGameOver) {
    LK.effects.flashScreen(0xff0000, 1000);
    LK.showGameOver();
    return;
  }
  var currentTime = Date.now();
  if (currentTime - lastUpdateTime > updateInterval) {
    if (direction.x !== -nextDirection.x || direction.y !== -nextDirection.y) {
      direction = nextDirection;
    }
    updateSnakePosition();
    checkFoodCollision();
    checkSelfCollision();
    lastUpdateTime = currentTime;
  }
});
// Touch input listener
game.on('down', handleTouchInput);
// Initialize game elements
initSnake();
initFood();