game.ex

def answer_question(%Game{current_question: current_question} = game, guess, user_name)
    when is_binary(guess) do
  game
  |> Response.new(guess, user_name)
  |> answer_question(game, user_name)
end

defp answer_question(%Response{correct: true} = response, game, user_name) do
  game =
    game
    |> increase_score_for_user(user_name)
    |> check_for_winning_user(user_name)
    |> select_question()

  {:ok, game}
end

defp answer_question(%Response{correct: false}, _game, _user_name) do
  {:error, :incorrect}
end