class HeartGauge {

	constructor(heartManager) {
		this.heartManager = heartManager;
		this.hearts = [];

		let self = this;
		this.heartManager.addOnChangeCountListener(
			function() { self.onChangeCountListener(); }
		);

		this.heartManager.addOnChangeMaxCountListener(
			function() { self.onChangeMaxCountListener(); }
		);

		let startPosX = GAME_SCREEN_SIZE.x - HeartGauge.GAP * 4;
		let posY = 30;
		for(let i = 0; i < HeartManager.HEART_MAX_COUNT; i++) {
			let heart = game.add.sprite(startPosX - i * HeartGauge.GAP, posY, "heart_full");
			heart.anchor.set(0.5);
			heart.scale.set(HeartGauge.HEART_SCALE);
			heart.alpha = 0;
			this.hearts.push(heart);
		}
	};

	onChangeCountListener() {
		this.updateHearts();
	}

	onChangeMaxCountListener() {
		this.updateHearts();
	}

	start() {
		this.updateHearts();
	}

	updateHearts() {
		for(let i = 0; i < this.heartManager.getMaxCount(); i++) {
			if(i < this.heartManager.getCount())
				this.hearts[i].loadTexture("heart_full");
			else
				this.hearts[i].loadTexture("heart_empty");

			this.hearts[i].alpha = 1;
		}
	}
}

HeartGauge.GAP				= 35;
HeartGauge.HEART_SCALE		= 0.6;