defmodule Irc.Parser.Capabs do
  @moduledoc "Helper to parse capability lists"
  @type t :: %{capab_name() => capab_value()}
  @type capab_name :: String.t()
  @type capab_value :: true | any()

  @spec parse(String.t()) :: t()
  def parse(string) do
    string
    |> String.split(" ")
    |> Enum.map(&parse_capab/1)
    |> Enum.into(Map.new)
  end

  defp parse_capab(string) do
    case String.split(string, "=", parts: 2) do
      [capab] ->
        {capab, true}
      [capab, args] ->
        parse_capab_with_args(capab, args)
    end
  end

  defp parse_capab_with_args(capab, args) do
    args = args
     |> String.split(",")
     |> Map.reduce(%{}, fn(k_v, acc) ->
        [k, v] = String.split(k_v, "=")
        Map.put(acc, k, v)
     end)
    {capab, args}
  end

end