defmodule Wiki.Rest do
  @moduledoc """
  Streamlined interface for reading pages and fetching basic information.

  See upstream references:
  - https://www.mediawiki.org/wiki/Parsoid/API
  - https://www.mediawiki.org/wiki/Specs/HTML
  - https://www.mediawiki.org/wiki/Special:MyLanguage/API:REST_API
  - https://www.mediawiki.org/wiki/API:REST_API/Reference
  - https://www.wikidata.org/wiki/Special:MyLanguage/Wikidata:REST_API

  Older backend:
  - https://www.mediawiki.org/wiki/Wikimedia_REST_API
  """

  @doc """
  Fetch rendered page HTML with RDFa annotations.

  ```
  Wiki.Rest.page_html(:enwiki, "Earth")
  ```
  """
  def page_html(site, title, _revision \\ nil) do
    Wiki.SiteMatrix.get!(site)
    |> rest_url("/page/#{title}/html")
    |> Tesla.get!()
  end

  def page_images(site, title) do
    Wiki.SiteMatrix.get!(site)
    |> rest_url("/page/#{title}/links/media")
    |> Tesla.get!()
  end

  defp rest_url(site, path) when is_struct(site, Wiki.SiteMatrix.Spec) do
    "#{site.base_url}/w/rest.php/v1#{path}"
  end
end