defmodule Openflow.Multipart.GroupFeatures.Request do
  defstruct(
    version: 4,
    xid: 0,
    # virtual field
    datapath_id: nil,
    aux_id: nil,
    flags: []
  )

  alias __MODULE__

  @type t :: %Request{
          version: 4,
          datapath_id: String.t(),
          aux_id: 0..0xFF | nil,
          xid: 0..0xFFFFFFFF
        }

  @spec ofp_type() :: 18
  def ofp_type, do: 18

  @spec new(xid :: 0..0xFFFFFFFF) :: t()
  def new(xid \\ 0), do: %Request{xid: xid}

  @spec read(<<>>) :: t()
  def read(""), do: %Request{}

  @spec to_binary(t()) :: binary()
  def to_binary(%Request{} = msg), do: Openflow.Multipart.Request.header(msg)
end