@intility/bifrost-react/dist/utils/getNextUpdateDelay.js

React library for Intility's design system, Bifrost.

/**
 * Calculate milliseconds until the next unit boundary for relative time updates
 * @param date The target date
 * @returns milliseconds until next update should occur
 */
export default function getNextUpdateDelay(date) {
  const now = new Date();
  const diffMs = now.getTime() - date.getTime();
  const absDiffMs = Math.abs(diffMs);
  const isFuture = diffMs < 0;
  const SECOND_MS = 1000;
  const MINUTE_MS = 60 * SECOND_MS;
  const HOUR_MS = 60 * MINUTE_MS;
  const DAY_MS = 24 * HOUR_MS;

  // If it's been 2+ days, update at the next day boundary
  if (absDiffMs >= 2 * DAY_MS) {
    const msIntoCurrentDay = absDiffMs % DAY_MS;
    return isFuture ? msIntoCurrentDay || DAY_MS : DAY_MS - msIntoCurrentDay;
  }

  // If it's been 2+ hours, update at the next hour boundary
  if (absDiffMs >= 2 * HOUR_MS) {
    const msIntoCurrentHour = absDiffMs % HOUR_MS;
    return isFuture ? msIntoCurrentHour || HOUR_MS : HOUR_MS - msIntoCurrentHour;
  }

  // If it's been 2+ minutes, update at the next minute boundary
  if (absDiffMs >= 2 * MINUTE_MS) {
    const msIntoCurrentMinute = absDiffMs % MINUTE_MS;
    return isFuture ? msIntoCurrentMinute || MINUTE_MS : MINUTE_MS - msIntoCurrentMinute;
  }

  // If it's been seconds, update at the next second boundary
  const msIntoCurrentSecond = absDiffMs % SECOND_MS;
  return isFuture ? msIntoCurrentSecond || SECOND_MS : SECOND_MS - msIntoCurrentSecond;
}