#!/usr/bin/env ruby

unless ARGV[0]
  puts <<EOS
Usage:
  ruby parse_volume.rb NUM

Example:
  ./parse_volume 12-15,19,23-29
  #=> 12 13 14 15 19 23 24 25 26 27 28 29
EOS
  exit
end

str = ARGV[0].gsub(/\s/, "")
vol = Array.new

if /^(?!^[^\d])(?!.*[^\d]$)(?!.*\,-)(?!.*-\,)(?!.*--)[-\,\d]*$/ =~ str
  str.split(',').each do |s|
    next if s.empty?

    pair = s.split('-')
    if pair.length > 1 # ex. a = "3-6" => (3..6).to_a
      vol.concat((pair[0].to_i..pair[1].to_i).to_a)
    else
      vol << pair[0].to_i
    end
  end

  vol.uniq!
  vol.sort!
  puts vol.join(' ')
else
  puts "Can't parse '#{str}'"
end