require 'facter'

# We only want this to run for Linux boxes with a 2.6+ kernel version
if Facter.value(:kernel) == 'Linux'

  sysfs_block_directory = '/sys/block/'

  blockdevices = []


  # This should prevent Linux boxes with < 2.6 kernels from running
  if File.exists?(sysfs_block_directory)

    # Iterate over each file in the /sys/block directory and skip ones that do not have a device subdirectory
    Dir.entries(sysfs_block_directory).each do |device|
      sysfs_device_directory = sysfs_block_directory + device + "/device"
      next unless File.exist?(sysfs_device_directory)

      # Add the device to the blockdevices list, which is returned as it's own fact later on
      blockdevices << device

      sizefile = sysfs_block_directory + device + "/size"

      if File.exist?(sizefile)
        Facter.add("#{device}_gb".to_sym) do
        confine :osfamily => 'RedHat'
          setcode { IO.read(sizefile).strip.to_i * 512 / 1073741824 }
        end
      end


    end
  end
end