function twoDigit(number: number): string {
  return ("0" + number).slice(-2);
}

function timestamp(date?: Date): string {
  date = date || new Date();
  return [ date.getFullYear(), twoDigit(date.getMonth() + 1), twoDigit(date.getDate()) ].join("-") +
    " " +
    [ twoDigit(date.getHours()), twoDigit(date.getMinutes()), twoDigit(date.getSeconds()) ].join(":");
}

export {
  timestamp
};