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

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

import keycode from 'keycode'

let shiftKeyPressed = false
let ctrlKeyPressed = false

/**
 * @return {Boolean}
 */
export const isShiftKeyPressed = () => shiftKeyPressed

/**
 * @return {Boolean}
 */
export const isCtrlKeyPressed = () => 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(element = document) {
	element.addEventListener('keydown', handleKeyDown)
	element.addEventListener('keyup', handleKeyUp)
}

init()