keplars

defmodule Keplars do
  @api_key_regex ~r/^kms_[a-f0-9]+\.(live|adm)_[a-f0-9]+$/
  @default_base_url "https://api.keplars.com"
  @default_max_retries 3
  @default_retry_delay_ms 1_000
  @default_timeout_ms 30_000

  defstruct [:api_key, :base_url, :max_retries, :retry_delay_ms, :timeout_ms]

  @type t :: %__MODULE__{
          api_key: String.t(),
          base_url: String.t(),
          max_retries: non_neg_integer(),
          retry_delay_ms: non_neg_integer(),
          timeout_ms: non_neg_integer()
        }

  def new(api_key \\ "", opts \\ []) do
    resolved_key =
      if api_key == "" or is_nil(api_key) do
        System.get_env("KEPLARS_API_KEY") || ""
      else
        api_key
      end

    if not Regex.match?(@api_key_regex, resolved_key) do
      {:error, "Invalid API key format. Expected: kms_<hex>.(live|adm)_<hex>"}
    else
      base_url =
        Keyword.get(opts, :base_url) ||
          System.get_env("KEPLARS_BASE_URL") ||
          @default_base_url

      client = %__MODULE__{
        api_key: resolved_key,
        base_url: String.trim_trailing(base_url, "/"),
        max_retries: Keyword.get(opts, :max_retries, @default_max_retries),
        retry_delay_ms: Keyword.get(opts, :retry_delay_ms, @default_retry_delay_ms),
        timeout_ms: Keyword.get(opts, :timeout_ms, @default_timeout_ms)
      }

      {:ok, client}
    end
  end
end