Formats a date with internationalization.

i18n-format-dates.mjs

/**
 * @typedef {Object} I18nFormatDateType - creates a new type named "I18nFormatDateType"
 * @property {string} [dateString] - The string representation of the date to be formatted. Defaults to current date.
 * @property {string} [locale="en-US"] - The locale (keyof typeof Intl.Locale) to use for formatting the date.
 * @property {Intl.DateTimeFormatOptions} [formatOptions] - The options for formatting the date.
 */

/**
 * Formats a date with internationalization.
 *
 * @param {I18nFormatDateType} options - The options for formatting the date.
 * @returns {string} - The formatted date string.
 *
 * @example
 *
 * const formattedDate = i18nFormatDate({
 *   dateString: "2023-06-10",
 *   locale: "de",
 *   formatOptions: { day: "numeric", month: "long", year: "numeric" }
 * });
 * console.log(formattedDate); // Output: "10. Juni 2023"
 */
export function i18nFormatDate(options) {
  const defaultFormatOptions = {
    day: "2-digit",
    month: "short",
    year: "numeric",
  };

  const {
    dateString,
    locale = "en-US",
    formatOptions = defaultFormatOptions,
  } = options;

  const date = dateString ? new Date(dateString) : new Date();

  if (dateString && isNaN(date.getTime())) {
    console.error(`Invalid date: ${dateString}`);
    return dateString;
  }

  return new Intl.DateTimeFormat(locale, formatOptions).format(date);
}