function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var EventEmitter = function () {
	function EventEmitter() {
		_classCallCheck(this, EventEmitter);

		this.observers = {};
	}

	EventEmitter.prototype.on = function on(events, listener) {
		var _this = this;

		events.split(' ').forEach(function (event) {
			_this.observers[event] = _this.observers[event] || [];
			_this.observers[event].push(listener);
		});
	};

	EventEmitter.prototype.off = function off(event, listener) {
		var _this2 = this;

		if (!this.observers[event]) {
			return;
		}

		this.observers[event].forEach(function () {
			if (!listener) {
				delete _this2.observers[event];
			} else {
				var index = _this2.observers[event].indexOf(listener);
				if (index > -1) {
					_this2.observers[event].splice(index, 1);
				}
			}
		});
	};

	EventEmitter.prototype.emit = function emit(event) {
		for (var _len = arguments.length, args = Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
			args[_key - 1] = arguments[_key];
		}

		if (this.observers[event]) {
			this.observers[event].forEach(function (observer) {
				observer.apply(undefined, args);
			});
		}

		if (this.observers['*']) {
			this.observers['*'].forEach(function (observer) {
				var _ref;

				observer.apply(observer, (_ref = [event]).concat.apply(_ref, args));
			});
		}
	};

	return EventEmitter;
}();

export default EventEmitter;