import { useState, useEffect } from "react";

const SECOND = 1_000;
const MINUTE = SECOND * 60;
const HOUR = MINUTE * 60;
const DAY = HOUR * 24;

export default function useTimer(deadline, interval = SECOND) {
  const [timespan, setTimespan] = useState(new Date(deadline) - Date.now());

  useEffect(() => {
    const intervalId = setInterval(() => {
      setTimespan((_timespan) => _timespan - interval);
    }, interval);

    return () => {
      clearInterval(intervalId);
    };
  }, [interval]);

  /* If the initial deadline value changes */
  useEffect(() => {
    setTimespan(new Date(deadline) - Date.now());
  }, [deadline]);
  
  function checkTime(i: string | number) {
    if (i < 10) i = "0" + i
    return i;
  }

// if want 0 before number return {
  //days: checkTime( Math.floor(timespan / DAY)),
// }

  return {
    days: Math.floor(timespan / DAY),
    hours: Math.floor((timespan / HOUR) % 24),
    minutes: Math.floor((timespan / MINUTE) % 60),
    seconds: Math.floor((timespan / SECOND) % 60)
  };
}

// usage
const { days, hours, minutes, seconds } = useTimer("2022-12-31T23:59:59");

(new Date(+timeStampinSeconds * 1000).toISOString()).slice(0, 19))