defmodule Waffle.Storage.Google.Url do
  @moduledoc """
  Defines an interface for generating Google Cloud Storage URLs.
  """

  alias Waffle.Types

  @doc """
  Constructs a URL based on data from Waffle.
  """
  @callback build(
              definition :: Types.definition(),
              version :: Types.version(),
              meta :: Types.meta(),
              options :: Keyword.t()
            ) :: String.t()

  defmacro __using__(_) do
    quote do
      @behaviour Waffle.Storage.Google.Url
      @before_compile Waffle.Storage.Google.Url
    end
  end

  defmacro __before_compile__(_) do
    quote do
      @doc """
      Same as `build(definition, version, meta, [])`.
      """
      @spec build(Types.definition(), Types.version(), Types.meta()) :: String.t()
      def build(definition, version, meta), do: build(definition, version, meta, [])
    end
  end
end