/****
* Classes
****/
// Enemy class
var Enemy = Container.expand(function () {
  var self = Container.call(this);
  var enemyGraphics = self.attachAsset('enemy', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.speed = 2;
  self.move = function () {
    self.y += self.speed;
  };
});
// EnemyBullet class
var EnemyBullet = Container.expand(function () {
  var self = Container.call(this);
  var bulletGraphics = self.attachAsset('enemyBullet', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.speed = 5;
  self.move = function () {
    self.y += self.speed;
  };
});
// Assets initialization will be handled automatically by the LK engine based on usage in the code.
// Hero class
var Hero = Container.expand(function () {
  var self = Container.call(this);
  var heroGraphics = self.attachAsset('hero', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.move = function (x, y) {
    self.x = x;
    self.y = y;
  };
  self.shoot = function () {
    var bullet = new HeroBullet();
    bullet.x = self.x;
    bullet.y = self.y - 50; // Shoot from above the hero
    game.addChild(bullet);
    bullets.push(bullet);
  };
});
// HeroBullet class
var HeroBullet = Container.expand(function () {
  var self = Container.call(this);
  var bulletGraphics = self.attachAsset('heroBullet', {
    anchorX: 0.5,
    anchorY: 0.5
  });
  self.speed = -10;
  self.move = function () {
    self.y += self.speed;
  };
});

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

/****
* Game Code
****/
var hero = game.addChild(new Hero());
hero.x = 1024; // Center horizontally
hero.y = 2500; // Near the bottom
var enemies = [];
var bullets = [];
var enemyBullets = [];
// Touch event to move the hero
game.on('down', function (obj) {
  var pos = obj.event.getLocalPosition(game);
  hero.move(pos.x, pos.y);
});
// Shoot a bullet on move
game.on('move', function (obj) {
  hero.shoot();
});
// Game tick
LK.on('tick', function () {
  // Move bullets
  for (var i = bullets.length - 1; i >= 0; i--) {
    bullets[i].move();
    if (bullets[i].y < 0) {
      // Bullet off-screen
      bullets[i].destroy();
      bullets.splice(i, 1);
    }
  }
  // Move enemy bullets
  for (var j = enemyBullets.length - 1; j >= 0; j--) {
    enemyBullets[j].move();
    if (enemyBullets[j].intersects(hero)) {
      // Hero hit
      LK.effects.flashScreen(0xff0000, 1000);
      LK.showGameOver();
    }
    if (enemyBullets[j].y > 2732) {
      // Bullet off-screen
      enemyBullets[j].destroy();
      enemyBullets.splice(j, 1);
    }
  }
  // Spawn enemies and their bullets
  if (LK.ticks % 120 == 0) {
    // Every 2 seconds
    var enemy = new Enemy();
    enemy.x = Math.random() * 2048;
    enemy.y = 0;
    enemies.push(enemy);
    game.addChild(enemy);
    var enemyBullet = new EnemyBullet();
    enemyBullet.x = enemy.x;
    enemyBullet.y = enemy.y + 50;
    enemyBullets.push(enemyBullet);
    game.addChild(enemyBullet);
  }
  // Move enemies
  for (var k = enemies.length - 1; k >= 0; k--) {
    enemies[k].move();
    if (enemies[k].y > 2732) {
      // Enemy off-screen
      enemies[k].destroy();
      enemies.splice(k, 1);
    }
  }
});