A simple Ruby shell script to control LIFX (http://lifx.co) light bulbs, adds color support

light.rb

#!/usr/bin/env ruby

require 'lifx'

available_colors = LIFX::Colors.instance_methods

if ARGV.length > 0
  # see if a specific lamp is addressed
  label = /^on|off|0x[0-9a-f]{6}$/.match(ARGV[0]) || available_colors.member?(ARGV[0]) ? nil : ARGV[0]

  # discover lamps and wait for label data to be available
  client = LIFX::Client.lan
  client.discover!
  sleep(0.3)

  # select either the specified light or all lights if none was specified
  light = label ? client.lights.with_label(label) : client.lights

  # transition duration in seconds
  duration = [4, ARGV[-1].to_i].max

  # value is either first or second argument, depending whether a label was provided
  value = label ? ARGV[1] : ARGV[0]

  ensure_light_on = Proc.new {
    if light.off?
      light.turn_on!
      sleep(0.2)
    end
  }

  if value == 'on'
    light.turn_on!
    sleep(0.2)
    light.set_color(LIFX::Color.rgb(255,255,255), duration: duration)
  elsif value == 'off' and light.on?
    light.set_color(LIFX::Color.rgb(0, 0, 0), duration: duration)
    sleep(duration)
    light.turn_off!
  elsif value[0,2] == '0x'
    r = value[2,2].hex
    g = value[4,2].hex
    b = value[6,2].hex

    ensure_light_on.call()

    color = LIFX::Color.rgb(r, g, b)
    light.set_color(color, duration: duration)
  elsif LIFX::Color.respond_to? value.to_sym
    ensure_light_on.call()
    color = LIFX::Color.send(value.to_sym)
    light.set_color(color, duration: duration)
  end

  # make sure all commands are send before the program exits
  client.flush
else
  print("usage: light [label] on|off|0xRRGGBB|color [duration=4]

  examples:
  light on            -> turns all lights on
  light \"Kitchen\" off -> turns Kitchen light off
  light 0xff0000      -> turns all lights red
  light Bedroom on 30 -> turns up the light in the Bedroom over 30 seconds
  light Bedroom green 10 -> turns green the light in the bedroom over 10 seconds

  The colors available for the color argument are:
  #{available_colors.collect(&:to_s).join(', ')}\n")
end