led-hands-rpi/main.rb

# frozen_string_literal: true

#!/usr/bin/env ruby

require 'bundler'
require 'sinatra'
require 'rpi_gpio'

Bundler.setup
Bundler.require

BLUE = 37
WHITE = 35
RED = 33
GREEN = 31
YELLOW = 29
LEDS = [BLUE, WHITE, RED, GREEN, YELLOW]

IO = RPi::GPIO
IO.set_numbering :board

LEDS.each do |led|
  IO.setup led, as: :output, initialize: :low
  IO.set_low led
end

# IO.reset

get '/' do
  @led_status = led_status
  erb :index
end

get '/cycle' do
  clear

  5.times do |i|
   sleep 0.5
   IO.set_high LEDS[i]
   IO.set_low LEDS[i - 1]
  end

  clear
  redirect to('/')
end

get '/led/:color' do |led|
  clear
  IO.set_high pick(led)

  redirect to('/')
end

def pick led
  case led
    when 'blue'
      BLUE
    when 'white'
      WHITE
    when 'red'
      RED
    when 'green'
      GREEN
    when 'yellow'
      YELLOW
  end
end

def clear
  LEDS.each do |led|
    IO.set_low led
  end
end

def led_status
  {
    blue: IO.high?(BLUE),
    white: IO.high?(WHITE),
    red: IO.high?(RED),
    green: IO.high?(GREEN),
    yellow: IO.high?(YELLOW)
  }
end