(function () {
  if (typeof Mario === "undefined") window.Mario = {};

  var Coin = (Mario.Coin = function (pos, sprite) {
    Mario.Entity.call(this, {
      pos: pos,
      sprite: sprite,
      hitbox: [0, 0, 16, 16],
    });
    this.idx = level.items.length;
  });

  Mario.Util.inherits(Coin, Mario.Entity);

  Coin.prototype.isPlayerCollided = function () {
    //the first two elements of the hitbox array are an offset, so let's do this now.
    var hpos1 = [this.pos[0] + this.hitbox[0], this.pos[1] + this.hitbox[1]];
    var hpos2 = [
      player.pos[0] + player.hitbox[0],
      player.pos[1] + player.hitbox[1],
    ];

    //if the hitboxes actually overlap
    if (
      !(
        hpos1[0] > hpos2[0] + player.hitbox[2] ||
        hpos1[0] + this.hitbox[2] < hpos2[0]
      )
    ) {
      if (
        !(
          hpos1[1] > hpos2[1] + player.hitbox[3] ||
          hpos1[1] + this.hitbox[3] < hpos2[1]
        )
      ) {
        this.collect();
      }
    }
  };

  Coin.prototype.render = function (ctx, vX, vY) {
    this.sprite.render(ctx, this.pos[0], this.pos[1], vX, vY);
  };

  //money is not affected by gravity, you see.
  Coin.prototype.update = function (dt) {
    this.sprite.update(dt);
  };
  Coin.prototype.checkCollisions = function () {
    this.isPlayerCollided();
  };

  Coin.prototype.collect = function () {
    sounds.coin.currentTime = 0.05;
    sounds.coin.play();
    player.coins += 1;
    delete level.items[this.idx];
  };
})();