tab reply

tab-reply.js

"use strict";
const input = document.getElementById('input');
const chat = document.getElementById('chat');

input.addEventListener('keydown', processKeydown);

function processKeydown(event) {
	if( event.which === 9 && input.value.length === 0 ) {
		event.preventDefault();
		const last = getLastReply();
		input.value  = `:${last} `;
	}
}

function getLastReply() {
	const mentions = chat.querySelectorAll('.mention');
	const lastMention = Array.from(mentions).pop();
	return lastMention.parentNode.parentNode.id.split('-')[1];
}