class Rufus::Scheduler::IntervalJob

def set_next_time(is_post, trigger_time)
  @next_time =
    if is_post
      Time.now + @interval
    elsif trigger_time.nil?
      if @first_at < Time.now
        Time.now + @interval
      else
        @first_at
      end
    else
      false
    end
end