asdf-games/lib/controls/KeyControls.js

class KeyControls {
  
	constructor() {
		this.keys = {};
		// Bind event handlers
		document.addEventListener("keydown", e => {
			if ([37, 38, 39, 40].indexOf(e.which) >= 0) {
				e.preventDefault();
			}
			this.keys[e.which] = true;
		}, false);
		document.addEventListener("keyup", e => {
			this.keys[e.which] = false;
		}, false);
	}

	get action() {
		// Spacebar
		return this.keys[32];
	}

	get ctrl() {
		// Control
		return this.keys[17];
	}

	get shift() {
		// Shift
		return this.keys[16];
	}

	get escape() {
		// Escape
		return this.keys[27];
	}

	get x() {
		// Arrow Left or A (WASD)
		if (this.keys[37] || this.keys[65]) {
			return -1;
		}
		// Arrow Right or D (WASD)
		if (this.keys[39] || this.keys[68]) {
			return 1;
		}
		return 0;
	}

	get y() {
		// Arrow Up or W (WASD)
		if (this.keys[38] || this.keys[87]) {
			return -1;
		}
		// Arrow Down or S (WASD)
		if (this.keys[40] || this.keys[83]) {
			return 1;
		}
		return 0;
	}

  
	key(key, value) {
		if (value !== undefined) {
			this.keys[key] = value;
		}
		return this.keys[key];
	}

	reset() {
		for (let key in this.keys) {
			this.keys[key] = false;
		}
	}

}

module.exports = KeyControls;