number_guess.ex

defmodule NumberGuess do
  use GenServer

  @moduledoc """
  Continue to implement the bakend of a number guesser game.

  Generates a number between 1 and 100 (inclusive), then tell the calling
  process whether it is too big, too small, or just right. Keep track of the
  number of guesses.
  """

  @enforce_keys [:secret_number, :guesses]
  defstruct secret_number: nil, guesses: nil
  @type t :: %NumberGuess{secret_number: pos_integer(), guesses: non_neg_integer()}

  @spec start_link() :: {:ok, pid}
  def start_link do
    GenServer.start_link(__MODULE__, {})
  end

  def init(_) do
    secret_number = :rand.uniform(100)
    {:ok, %NumberGuess{secret_number: secret_number, guesses: 0}}
  end

  @doc """
  Make a guess.
  """
  @spec guess(pid(), integer()) :: :correct | :too_high | :too_low
  def guess(_pid, _guess) do
    # IMPLEMENT
    :too_low
  end

  @doc """
  The number of guesses made so far.
  """
  @spec guesses(pid) :: non_neg_integer()
  def guesses(_pid) do
    ## IMPLEMENT
    0
  end
end