merchant

defmodule Merchant.Client do
  @moduledoc """
  Client for the Merchant API.
  """

  @api_version "2024-09-01"

  @type method :: :head | :get | :delete | :trace | :options | :post | :put | :patch

  @type error :: {:error, Tesla.Env.t()}

  @spec client :: Tesla.Client.t()
  def client do
    base_url = Application.get_env(:merchant, :base_url)
    api_key = Application.get_env(:merchant, :api_key)

    if is_nil(base_url) do
      raise "REVOLUT_BASE_URL is not set"
    end

    if is_nil(api_key) do
      raise "REVOLUT_API_KEY is not set"
    end

    Tesla.client([
      {Tesla.Middleware.BaseUrl, base_url},
      {Tesla.Middleware.Headers,
       [
         {"Authorization", "Bearer #{api_key}"},
         {"Revolut-Api-Version", @api_version}
       ]},
      {Tesla.Middleware.JSON, engine: JSON}
    ])
  end

  @spec req(method(), String.t(), term(), Keyword.t(), Keyword.t(), Keyword.t()) ::
          {:ok, term()} | error()
  def req(method, path, body \\ nil, params \\ [], headers \\ [], opts \\ []) do
    case Tesla.request(client(),
           method: method,
           url: path,
           body: body,
           query: params,
           headers: headers,
           opts: opts
         ) do
      {:ok, %Tesla.Env{status: status, body: body}} when status < 400 ->
        {:ok, body}

      {:error, error} ->
        {:error, error}
    end
  end

  @spec req!(method(), String.t(), term(), Keyword.t(), Keyword.t(), Keyword.t()) :: term()
  def req!(method, path, body \\ nil, params \\ [], headers \\ [], opts \\ []) do
    case req(method, path, body, params, headers, opts) do
      {:ok, body} -> body
      {:error, error} -> raise error
    end
  end
end