/****
* Classes
****/
// Food class
var Food = Container.expand(function () {
  var self = Container.call(this);
  var food = LK.getAsset('food', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.addChild(food);
  self.randomizePosition = function () {
    self.x = Math.floor(Math.random() * 2048);
    self.y = Math.floor(Math.random() * 2732);
  };
  self.randomizePosition();
});
//<Assets used in the game will automatically appear here>
// Snake class
var Snake = Container.expand(function () {
  var self = Container.call(this);
  self.segments = [];
  self.direction = {
    x: 1,
    y: 0
  };
  self.speed = 10;
  self.grow = false;
  self.init = function () {
    // Initialize the snake with 3 segments
    for (var i = 0; i < 3; i++) {
      var segment = self.addSegment(1024 - i * 20, 1366);
      self.segments.push(segment);
    }
  };
  self.addSegment = function (x, y) {
    var segment = LK.getAsset('snakeSegment', {
      anchorX: 0.5,
      anchorY: 0.5
    });
    segment.x = x;
    segment.y = y;
    game.addChild(segment);
    return segment;
  };
  self.update = function () {
    // Move the snake
    var head = self.segments[0];
    var newX = head.x + self.direction.x * self.speed;
    var newY = head.y + self.direction.y * self.speed;
    // Check for collisions with walls
    if (newX < 0 || newX > 2048 || newY < 0 || newY > 2732) {
      LK.showGameOver();
      return;
    }
    // Check for collisions with itself
    for (var i = 1; i < self.segments.length; i++) {
      if (newX === self.segments[i].x && newY === self.segments[i].y) {
        LK.showGameOver();
        return;
      }
    }
    // Move the segments
    for (var i = self.segments.length - 1; i > 0; i--) {
      self.segments[i].x = self.segments[i - 1].x;
      self.segments[i].y = self.segments[i - 1].y;
    }
    head.x = newX;
    head.y = newY;
    // Grow the snake
    if (self.grow) {
      var tail = self.segments[self.segments.length - 1];
      var newSegment = self.addSegment(tail.x, tail.y);
      self.segments.push(newSegment);
      self.grow = false;
    }
  };
  self.changeDirection = function (newDirection) {
    // Prevent the snake from reversing
    if (self.direction.x + newDirection.x !== 0 || self.direction.y + newDirection.y !== 0) {
      self.direction = newDirection;
    }
  };
  self.init();
});

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

/****
* Game Code
****/
var snake = new Snake();
game.addChild(snake);
var food = new Food();
game.addChild(food);
game.update = function () {
  snake.update();
  // Check for collision with food
  if (snake.segments[0].x === food.x && snake.segments[0].y === food.y) {
    snake.grow = true;
    food.randomizePosition();
  }
};
// Handle touch events for direction change
game.down = function (x, y, obj) {
  var head = snake.segments[0];
  if (x < head.x) {
    snake.changeDirection({
      x: -1,
      y: 0
    });
  } else if (x > head.x) {
    snake.changeDirection({
      x: 1,
      y: 0
    });
  } else if (y < head.y) {
    snake.changeDirection({
      x: 0,
      y: -1
    });
  } else if (y > head.y) {
    snake.changeDirection({
      x: 0,
      y: 1
    });
  }
};