defmodule Cepis.RetryTest do
  use Cepis.ServerCase

  test "a 500 is retried and the second attempt wins", %{server: server, client: client} do
    FakeServer.respond(server, "/01001000", [
      {500, json(%{"erro" => "interno"}), []},
      {200, json(address_fixture()), []}
    ])

    assert {:ok, address} = Cepis.lookup("01001000", client)
    assert address.localidade == "São Paulo"
    assert FakeServer.count(server, "/01001000") == 2
  end

  test "attempts are exhausted and then it gives up", %{server: server, client: client} do
    FakeServer.respond(server, "/01001000", {503, json(%{"erro" => "interno"}), []})

    assert {:error, %Cepis.ServerError{status: 503}} = Cepis.lookup("01001000", client)
    assert FakeServer.count(server, "/01001000") == 3
  end

  test "max_attempts: 1 disables retrying", %{server: server} do
    client = Cepis.Client.new(base_url: server.url, max_attempts: 1, timeout: 5_000)
    FakeServer.respond(server, "/01001000", {500, "{}", []})

    assert {:error, %Cepis.ServerError{status: 500}} = Cepis.lookup("01001000", client)
    assert FakeServer.count(server, "/01001000") == 1
  end

  test "a 429 exposes Retry-After in milliseconds", %{server: server, client: client} do
    FakeServer.respond(server, "/01001000", {429, "{}", [{"retry-after", "7"}]})

    assert {:error, %Cepis.RateLimitError{retry_after: 7_000}} = Cepis.lookup("01001000", client)
  end

  test "a Retry-After HTTP date is understood", %{server: server, client: client} do
    date =
      DateTime.utc_now()
      |> DateTime.add(30, :second)
      |> Calendar.strftime("%a, %d %b %Y %H:%M:%S GMT")

    FakeServer.respond(server, "/01001000", {429, "{}", [{"retry-after", date}]})

    assert {:error, %Cepis.RateLimitError{retry_after: retry_after}} =
             Cepis.lookup("01001000", client)

    assert retry_after > 20_000
    assert retry_after <= 30_000
  end

  test "an absurd Retry-After cannot park the caller", %{server: server, client: client} do
    FakeServer.respond(server, "/01001000", {429, "{}", [{"retry-after", "3600"}]})

    {elapsed, result} = :timer.tc(fn -> Cepis.lookup("01001000", client) end, :millisecond)

    assert {:error, %Cepis.RateLimitError{}} = result
    assert elapsed < 2_000
  end

  test "nothing listening is a network error" do
    client =
      Cepis.Client.new(
        base_url: "http://127.0.0.1:1",
        max_attempts: 2,
        backoff_base: 1,
        timeout: 1_000
      )

    assert {:error, %Cepis.NetworkError{}} = Cepis.lookup("01001000", client)
  end

  test "total_timeout bounds the whole call", %{server: server} do
    client =
      Cepis.Client.new(
        base_url: server.url,
        max_attempts: 50,
        backoff_base: 50,
        backoff_max: 50,
        total_timeout: 300
      )

    FakeServer.respond(server, "/01001000", {500, "{}", []})

    {elapsed, result} = :timer.tc(fn -> Cepis.lookup("01001000", client) end, :millisecond)

    assert {:error, %Cepis.ServerError{}} = result
    assert elapsed < 3_000
    assert FakeServer.count(server, "/01001000") < 50
  end
end