03-a-simple-modification

index.mjs

import { EventEmitter } from "events";

(function (number, callback) {
    const EMITTER = new EventEmitter;
    const MILLISECONDS_INTERVAL = 50;
    let ticks = 0;
    let elapsedTimeInMilliseconds = 0;
    let intervalID;

    function start() {
        process.nextTick(tick);
        intervalID = setInterval(itirate, MILLISECONDS_INTERVAL)
    }

    function itirate() {
        if (elapsedTimeInMilliseconds >= number) return stop();

        elapsedTimeInMilliseconds += MILLISECONDS_INTERVAL;
        tick();
    }
    
    function tick() {
        EMITTER.emit('tick');
        ticks++;
    }

    function stop() {
        clearInterval(intervalID);
        return callback(null, ticks)
    }

    start();

    return EMITTER;
})(1000, (error, result) => {
    if (error) {
        console.error(error)
    } else {
        console.log(`Number of ticks: ${result}`)
    }
}).on('tick', () => console.log('Tick'))