pdf_shift

defmodule PDFShift.Client do
  @moduledoc """
  HTTP client for PDFShift API.
  """

  @behaviour PDFShift.ClientBehaviour

  @doc """
  Performs a GET request to the PDFShift API.
  """
  @impl true
  @spec get(PDFShift.Config.t(), String.t(), keyword()) :: {:ok, map()} | {:error, any()}
  def get(config, endpoint, client_opts \\ []) do
    url = "#{config.base_url}#{endpoint}"

    Req.get(
      url,
      [
        auth: {:basic, "api:#{config.api_key}"},
        receive_timeout: Keyword.get(client_opts, :timeout, 30_000),
        retry: Keyword.get(client_opts, :retry, retry_options()),
        connect_options: [protocols: [:http1]],
        json: true
      ] ++ retry_delay_opts(client_opts)
    )
    |> handle_response()
  end

  @doc """
  Performs a POST request to the PDFShift API.
  """
  @impl true
  @spec post(PDFShift.Config.t(), String.t(), map(), keyword()) :: {:ok, map()} | {:error, any()}
  def post(config, endpoint, payload, client_opts \\ []) do
    url = "#{config.base_url}#{endpoint}"

    Req.post(
      url,
      [
        auth: {:basic, "api:#{config.api_key}"},
        json: payload,
        receive_timeout: Keyword.get(client_opts, :timeout, 60_000),
        retry: Keyword.get(client_opts, :retry, retry_options()),
        connect_options: [protocols: [:http1]]
      ] ++ retry_delay_opts(client_opts)
    )
    |> handle_response()
  end

  defp retry_options do
    if Application.get_env(:pdf_shift, :test_mode) do
      # No retries in test mode to speed up tests
      false
    else
      :safe_transient
    end
  end

  # In test mode, force retry_delay to 0 so any retry-enabled test doesn't wait on backoff.
  # Outside test mode, omit the option entirely and let Req use its default backoff.
  defp retry_delay_opts(client_opts) do
    if Keyword.has_key?(client_opts, :retry_delay) do
      [retry_delay: Keyword.fetch!(client_opts, :retry_delay)]
    else
      if Application.get_env(:pdf_shift, :test_mode) do
        [retry_delay: 0]
      else
        []
      end
    end
  end

  defp handle_response({:ok, %{status: status} = response}) when status in 200..299 do
    {:ok, response}
  end

  defp handle_response({:ok, %{status: _status, body: body}}) when is_map(body) do
    error_message = Map.get(body, "error", "Unknown error")
    {:error, error_message}
  end

  defp handle_response({:ok, %{status: _status, body: body}}) when is_binary(body) do
    # Try to parse JSON body
    case Jason.decode(body) do
      {:ok, decoded_body} when is_map(decoded_body) ->
        error_message = Map.get(decoded_body, "error", "Unknown error")
        {:error, error_message}

      _ ->
        {:error, "Unknown error"}
    end
  end

  defp handle_response({:error, exception}) do
    {:error, exception}
  end
end