@bigfishtv/cockpit/es/utils/selectKeyUtils.js

/**
 * Select Key Utilities
 * @module Utilities/selectKeyUtils
 */

import keycode from 'keycode';

var shiftKeyPressed = false;
var ctrlKeyPressed = false;

/**
 * @return {Boolean}
 */
export var isShiftKeyPressed = function isShiftKeyPressed() {
	return shiftKeyPressed;
};

/**
 * @return {Boolean}
 */
export var isCtrlKeyPressed = function isCtrlKeyPressed() {
	return ctrlKeyPressed;
};

/**
 * Callback to 'keydown' listener sets ctrl/shift down vars
 * @param  {Object} event - native key down event
 */
function handleKeyDown(event) {
	switch (keycode(event)) {
		case 'shift':
			shiftKeyPressed = true;
			break;
		case 'ctrl':
			ctrlKeyPressed = true;
			break;
		case 'command':
		case 'left command':
		case 'right command':
			ctrlKeyPressed = true;
			break;
	}
}

/**
 * Callback to 'keyup' listener sets ctrl/shift down vars
 * @param  {Object} event - native key down event
 */
function handleKeyUp(event) {
	switch (keycode(event)) {
		case 'shift':
			shiftKeyPressed = false;
			break;
		case 'ctrl':
			ctrlKeyPressed = false;
			break;
		case 'command':
		case 'left command':
		case 'right command':
			ctrlKeyPressed = false;
			break;
	}
}

/**
 * Attaches 'keydown' and 'keyup' event listeners to document
 * @param  {document} [element=document] - which element to attach event listeners to
 */
function init() {
	var element = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : document;

	element.addEventListener('keydown', handleKeyDown);
	element.addEventListener('keyup', handleKeyUp);
}

init();