/**
 * Get a `YYYY-MM-DD` string.
 * 
 * @param {Date} date 
 */
export default function dateStr(date) {
  function pad(n) {
    return n < 10 ? "0" + n : n.toString();
  }

  if (!(date instanceof Date)) {
    date = new Date(date);
  }

  return `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())}`;
}