Parse a string "1 year, 2 months, 5 minutes" into DateTime

PrettyTimeParser.scala

object PrettyTimeParser {
  private val YEAR_REGEX = """(?<YEAR>\d+)\s*years?""".r
  private val MONTH_REGEX = """(?<MONTH>\d+)\s*months?""".r
  private val WEEK_REGEX = """(?<WEEK>\d+)\s*weeks?""".r
  private val DAY_REGEX = """(?<DAY>\d+)\s*days?""".r
  private val HOUR_REGEX = """(?<HOUR>\d+)\s*hours?""".r
  private val MINUTE_REGEX = """(?<MINUTE>\d+)\s*minutes?""".r

  private def lookup(regex: scala.util.matching.Regex, s: String): Int = {
    Try(regex.findAllIn(s).toList.headOption.map(_.split(" ")).map(_(0).toInt)).getOrElse(None).getOrElse(0)
  }

  def parse(str: String): Option[DateTime] = {
    val year = lookup(YEAR_REGEX, str)
    val month = lookup(MONTH_REGEX, str)
    val week = lookup(WEEK_REGEX, str)
    val day = lookup(DAY_REGEX, str)
    val hour = lookup(HOUR_REGEX, str)
    val minute = lookup(MINUTE_REGEX, str)

    val now = DateTime.now()

    val dt = DateTime.now().plusYears(year)
      .plusMonths(month)
      .plusWeeks(week)
      .plusDays(day)
      .plusHours(hour)
      .plusMinutes(minute)

    if (dt.isAfter(now.getMillis)) Option(dt) else None
  }

}