Pomodoro timer for ubuntu unity

pomodoro.rb

#!/usr/bin/env ruby
#
# Pomodoro script.
#
# Displays a notification after given minutes.
# Use pomodoro.rb with args 10 = 10 min, 10s = 10 seconds
#
# Don't forget to 'sudo apt-get install libnotify-bin'
#

system "notify-send -i face-cool 'Go go go!'"

min = ARGV[0].to_i
if /^\d+s$/.match(min.to_s)
  min = min.to_s[0..-1]
  sec = true
else
  sec = false
end

min.times do |n|
  puts min - n
  sleep 60 if not sec unless sleep 1
end

system "notify-send -i face-cool -t 0 'End of Pomodoro!'"