Function formatISO9075

pkgs/core/src/formatISO9075/index.ts:47–89

(
  date: DateArg<Date> & {},
  options?: FormatISO9075Options,
)

 * //=> '19:00:52'
 */
export function formatISO9075(
  date: DateArg<Date> & {},
  options?: FormatISO9075Options,
): string {
  const date_ = toDate(date, options?.in);

  if (!isValid(date_)) {
    throw new RangeError("Invalid time value");
  }

  const format = options?.format ?? "extended";
  const representation = options?.representation ?? "complete";

  let result = "";

  const dateDelimiter = format === "extended" ? "-" : "";
  const timeDelimiter = format === "extended" ? ":" : "";

  // Representation is either 'date' or 'complete'
  if (representation !== "time") {
    const day = addLeadingZeros(date_.getDate(), 2);
    const month = addLeadingZeros(date_.getMonth() + 1, 2);
    const year = addLeadingZeros(date_.getFullYear(), 4);

    // yyyyMMdd or yyyy-MM-dd.
    result = `${year}${dateDelimiter}${month}${dateDelimiter}${day}`;
  }

  // Representation is either 'time' or 'complete'
  if (representation !== "date") {
    const hour = addLeadingZeros(date_.getHours(), 2);
    const minute = addLeadingZeros(date_.getMinutes(), 2);
    const second = addLeadingZeros(date_.getSeconds(), 2);

    // If there's also date, separate it with time with a space
    const separator = result === "" ? "" : " ";

    // HHmmss or HH:mm:ss.
    result = `${result}${separator}${hour}${timeDelimiter}${minute}${timeDelimiter}${second}`;
  }

  return result;
}