@intility/bifrost-react/dist/hooks/useRelativeTime.js

React library for Intility's design system, Bifrost.

"use client";

import { c as _c } from "react-compiler-runtime";
import { useMemo } from "react";
import useLocale from "./useLocale.js";
import getDuration from "../utils/getDuration.js";
// cache each formatter as it is created
const relativeFormattersCache = {};
function getRelativeTimeFormatter(locale, options) {
  // todo: figure out if this is actually less expensive than creating a new formatter
  const key = JSON.stringify({
    locale,
    options
  });
  let formatter = relativeFormattersCache[key];
  if (!formatter || typeof formatter.format !== "function") {
    formatter = new Intl.RelativeTimeFormat(locale, options);
    relativeFormattersCache[key] = formatter;
  }
  return formatter;
}

/**
 * Relative time formatter using locale and options from the current Bifrost
 * context (can be overridden).
 *
 * @param date - The date to format relative to now
 * @param options - Optional Configuration options
 * @param options.locale - Optional locale override (defaults to current Bifrost locale, e.g. "en-us" or "nb-no")
 * @param options.options - Optional Intl.RelativeTimeFormatOptions override (default `{ numeric: "auto", style: "long" }`)
 * @returns {string} A formatted relative time string (e.g. "5 minutes ago" or "in 2 hours")
 *
 * @see https://bifrost.intility.com/react/useRelativeTime
 *
 * @example
 * // e.g. "5 minutes ago" or "in 2 hours" depending on the date provided
 * const relativeTime = useRelativeTime(dateObjectOrISOString);
 */
export default function useRelativeTime(date, t0) {
  const $ = _c(2);
  const {
    locale: localeOverride,
    options: optionsOverride
  } = t0 === undefined ? {} : t0;
  const {
    dateOptions
  } = useLocale();
  let t1;
  if ($[0] !== date) {
    t1 = typeof date === "string" ? new Date(date) : date;
    $[0] = date;
    $[1] = t1;
  } else {
    t1 = $[1];
  }
  const dateObj = t1;
  const locale = localeOverride ?? dateOptions.locale;
  const options = optionsOverride ?? dateOptions.relativeTime;
  const now = new Date();
  const [unit, duration] = getDuration(now, dateObj);
  return getRelativeTimeFormatter(locale, options).format(duration, unit);
}