bio-miga/miga

require 'miga/result/base'

##
# Helper module including date-specific functions for results.
module MiGA::Result::Dates
  include MiGA::Result::Base

  ##
  # Returns the start date of processing as Time or +nil+ if it doesn't
  # exist.
  def started_at
    date_at :start
  end

  ##
  # Returns the end (done) date of processing as Time or +nil+ if it doesn't
  # exist.
  def done_at
    date_at :done
  end

  ##
  # Time it took for the result to complete as Float in minutes.
  def running_time
    a = started_at or return nil
    b = done_at or return nil
    (b - a).to_f / 60.0
  end

  private

  ##
  # Internal function to detect start and end dates
  def date_at(event)
    date = self[event]
    date ||= self[:started] if event == :start
    if date.nil?
      f = path event
      date = File.read(f) if File.size? f
    end
    Time.parse(date) unless date.nil?
  end
end