books/client/ui/keyboard.js

module.exports = {
	bindKey(element, key, listener) {
		element.addEventListener('keydown', (e) => {
			if (key === this.getKey(e)) {
				listener(e);
			}
		})
	},

	getKey(e) {
		var keycode = e.keyCode || e.which;
		var key = this.keyMap[keycode] || String.fromCharCode(keycode);

		if(e.ctrlKey || e.metaKey) {
			// add ctrl+ the key
			key = 'ctrl+' + key;
		}
		if(e.shiftKey) {
			// add ctrl+ the key
			key = 'shift+' + key;
		}
		return key.toLowerCase();
	},

	keyMap: {
		8: 'backspace',
		9: 'tab',
		13: 'enter',
		16: 'shift',
		17: 'ctrl',
		91: 'meta',
		18: 'alt',
		27: 'escape',
		37: 'left',
		39: 'right',
		38: 'up',
		40: 'down',
		32: 'space'
	},
}