Foam Missile Launcher Control in Ruby

rocket_launcher.rb

#!/usr/bin/env ruby

Version = '0.1'

abort("Usage: #{__FILE__} idVendor:idProduct") if ARGV.empty?

require 'curses'
require 'libusb'

# Add your own idVendor, idProduct, and movement codes here!
ActionData = {
  {
    :idVendor  => 0x0a81, 
    :idProduct => 0x0701
  } => {
    :up    => 0x02,
    :down  => 0x01,
    :left  => 0x04,
    :right => 0x08,
    :fire  => 0x10,
    :stop  => 0x20,
  },
}

class RocketLauncher
  attr_accessor :device

  def move(symbol)
    @usb.control_transfer(
      :bmRequestType => 0x21,
      :bRequest      => 0x09,
      :wValue        => 0x0000,
      :wIndex        => 0x0000,
      :dataOut       => ActionData[{
        :idVendor  => device[:idVendor], 
        :idProduct => device[:idProduct]
      }][symbol].chr
    )
  end

  def start
    begin
      @usb = LIBUSB::Context.new.devices(
        :idVendor  => device[:idVendor],
        :idProduct => device[:idProduct]
      ).first.open.claim_interface(0)
    rescue LIBUSB::ERROR_ACCESS
      abort("No permission to access USB device!")
    rescue LIBUSB::ERROR_BUSY
      abort("The USB device is busy!")
    rescue NoMethodError
      abort("Could not find USB device!")
    end
  
    Curses.noecho
    Curses.init_screen
    Curses.stdscr.keypad(true)
    Curses.timeout = 150
    Curses.addstr("USB Rocket Launcher Controller v#{Version} by Maxwell Pray")

    loop do
      Curses.setpos(2,0)

      case Curses.getch
        when Curses::Key::UP, 'w', 'W'
          Curses.addstr("Movement: Up!")
          self.move(:up)
        when Curses::Key::DOWN, 's', 'S'
          Curses.addstr("Movement: Down!")
          self.move(:down)
        when Curses::Key::LEFT, 'a', 'A'
          Curses.addstr("Movement: Left!")
          self.move(:left)
        when Curses::Key::RIGHT, 'd', 'D'
          Curses.addstr("Movement: Right!")
          self.move(:right)
        when Curses::Key::ENTER, 10, ' '
          Curses.addstr("Movement: Fire!")
          self.move(:fire)
        when 27, 'q', 'Q'
          exit
        else
          Curses.addstr("Waiting for key...")
          self.move(:stop)
      end

      Curses.clrtoeol
    end
  end
end


launcher = RocketLauncher.new

device = ARGV[0].split(':').map { |id| id.to_i(base=16) }
launcher.device = {
  :idVendor  => device[0],
  :idProduct => device[1]
}