module USBUtils

# File lib/usbutils.rb, line 16
def devices
  devices = []
  Dir.glob("/sys/bus/usb/devices/usb*") do |device|
    set_device(devices, device, 0, 0)
  end
  usb = LIBUSB::Context.new
  usb.devices.each do |usbdev|
    device = devices.select {|item| item[:serial] == usbdev.serial_number}.first
    device[:usbdev] = usbdev if device
  end
  devices
end

# File lib/usbutils.rb, line 9
def find_by(by, value)
  devices.each do |device|
    return device if device[by.to_sym] == value
  end
  raise "device not found: #{by}:#{value}"
end

# File lib/usbutils.rb, line 29
def set_device(devices, devpath, parent, level)
  return unless FileTest::directory?(devpath)
  Dir.chdir(devpath) do
    next unless File.exists? "busnum"
    busnum = `cat busnum`.chomp
    if File.exists? "serial"
      devnum       = `cat devnum`.chomp
      idvendor     = `cat idVendor`.chomp
      idproduct    = `cat idProduct`.chomp
      manufacturer = `cat manufacturer`.chomp
      product      = `cat product`.chomp
      serial       = `cat serial`.chomp
      devices << {
        :serial       => serial,
        :idvendor     => idvendor,
        :idproduct    => idproduct,
        :manufacturer => manufacturer,
        :product      => product,
      }
    end
    Dir.glob("#{devpath}/#{busnum}-*") do |subdev|
      subdev = subdev.chomp
      set_device devices, subdev, devnum, level + 1
    end
  end
end