/****
* Classes
****/
// Enemy ship class
var EnemyShip = Container.expand(function () {
  var self = Container.call(this);
  var enemyGraphics = self.attachAsset('enemyShip', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.speed = 2;
  self.update = function () {
    self.y += self.speed;
    if (self.y > 2732) {
      // Reset enemy position if it goes off screen
      self.y = -50;
      self.x = Math.random() * 2048;
    }
  };
});
// Player bullet class
var PlayerBullet = Container.expand(function () {
  var self = Container.call(this);
  var bulletGraphics = self.attachAsset('playerBullet', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.speed = -10;
  self.update = function () {
    self.y += self.speed;
  };
});
// Player spaceship class
var PlayerShip = Container.expand(function () {
  var self = Container.call(this);
  var shipGraphics = self.attachAsset('playerShip', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.move = function (x, y) {
    self.x = x;
    self.y = y;
  };
});

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

/****
* Game Code
****/
// Initialize player spaceship asset
// Initialize enemy ship asset
// Initialize bullet asset for the player
var playerShip = game.addChild(new PlayerShip());
playerShip.x = 1024; // Center horizontally
playerShip.y = 2400; // Position towards the bottom
var enemies = [];
var bullets = [];
var score = 0;
// Create enemies
for (var i = 0; i < 5; i++) {
  var enemy = new EnemyShip();
  enemy.x = Math.random() * 2048;
  enemy.y = Math.random() * -500; // Start off-screen
  enemies.push(enemy);
  game.addChild(enemy);
}
// Touch event to move player ship
game.on('down', function (obj) {
  var pos = obj.event.getLocalPosition(game);
  playerShip.move(pos.x, pos.y);
});
// Shoot bullet on touch
game.on('up', function () {
  var bullet = new PlayerBullet();
  bullet.x = playerShip.x;
  bullet.y = playerShip.y - 50;
  bullets.push(bullet);
  game.addChild(bullet);
});
// Game tick event
LK.on('tick', function () {
  // Update bullets
  for (var b = bullets.length - 1; b >= 0; b--) {
    bullets[b].update();
    if (bullets[b].y < 0) {
      bullets[b].destroy();
      bullets.splice(b, 1);
    }
  }
  // Update enemies
  for (var e = enemies.length - 1; e >= 0; e--) {
    enemies[e].update();
    // Check collision with bullets
    for (var b = bullets.length - 1; b >= 0; b--) {
      if (enemies[e].intersects(bullets[b])) {
        enemies[e].destroy();
        enemies.splice(e, 1);
        bullets[b].destroy();
        bullets.splice(b, 1);
        score += 1;
        break;
      }
    }
  }
  // Add more enemies if needed
  if (enemies.length < 5) {
    var enemy = new EnemyShip();
    enemy.x = Math.random() * 2048;
    enemy.y = Math.random() * -500; // Start off-screen
    enemies.push(enemy);
    game.addChild(enemy);
  }
});