Ring clock for ws2812 led

ring_clock.rb

#!/usr/bin/env ruby
$:.unshift(File.expand_path('../../lib', __FILE__))
require 'ws2812'

class Ring
  attr_accessor :led_count
  def initialize(number_of_leds)
    @led_count = number_of_leds
  end

  def ws
    return @ws if defined? @ws
    # +n+ leds at pin 18, using defaults
    @ws = Ws2812::Basic.new(led_count, 18)
    @ws.open
  end

  def get_led_rgb(number)
    [ws[number].r, ws[number].g, ws[number].b]
  end

  def set_led_off(number)
    ws.set number, 0, 0, 0
    ws.show
  end

  def set_led_rgb(number, r, g, b)
    return if get_led_rgb(number) == [r, g, b]
    ws.set number, r, g, b
    ws.show
  end

  def brightness=(level)
    ws.brightness = level
    ws.show
  end

  def normalize_on_range(value, range)
    (value / (range.to_f / (led_count - 1) )).to_i
  end
end

r = Ring.new(24)
hour_color = [14, 199, 33]
min_color = [0, 5, 199]
sec_color = [140, 14, 14]
old_hour_led = 0
old_min_led = 0
old_sec_led = 0
while true
  t = Time.now
  hour_led = t.hour
  min_led = r.normalize_on_range(t.min, 60)
  sec_led = r.normalize_on_range(t.sec, 60)
  if hour_led != old_hour_led ||
    [old_min_led, old_sec_led].include?(hour_led)
    r.set_led_off old_hour_led
    r.set_led_rgb hour_led, *hour_color
    old_hour_led = hour_led
  end
  if min_led != old_min_led ||
    [old_hour_led, old_sec_led].include?(min_led)
    r.set_led_off old_min_led unless hour_led == old_min_led
    r.set_led_rgb min_led, *min_color
    old_min_led = min_led
  end
  if sec_led != old_sec_led
    r.set_led_off old_sec_led unless [hour_led, min_led].include? old_sec_led
    r.set_led_rgb sec_led, *sec_color
    old_sec_led = sec_led
  end
  sleep 1
end