# frozen_string_literal: true

class SiteInspector
  class Endpoint
    class Content < Check
      # Given a path (e.g, "/data"), check if the given path exists on the canonical endpoint
      def path_exists?(path)
        endpoint.up? && endpoint.request(path: path, followlocation: true).success?
      end

      # The default Check#response method is from a HEAD request
      # The content check has a special response which includes the body from a GET request
      def response
        @response ||= endpoint.request(method: :get)
      end

      def document
        require 'nokogiri'
        @doc ||= Nokogiri::HTML response.body if response
      end
      alias doc document

      def body
        @body ||= document.to_s.force_encoding('UTF-8').encode('UTF-8', invalid: :replace, replace: '')
      end

      def robots_txt?
        @bodts_txt ||= path_exists?('robots.txt') if proper_404s?
      end

      def sitemap_xml?
        @sitemap_xml ||= path_exists?('sitemap.xml') if proper_404s?
      end

      def humans_txt?
        @humans_txt ||= path_exists?('humans.txt') if proper_404s?
      end

      def doctype
        document.internal_subset.external_id
      end

      def generator
        @generator ||= begin
          tag = document.at('meta[name="generator"]')
          tag['content'] if tag
        end
      end

      def prefetch
        return unless endpoint.up?

        options = SiteInspector.typhoeus_defaults.merge(followlocation: true)
        ['robots.txt', 'sitemap.xml', 'humans.txt', random_path].each do |path|
          request = Typhoeus::Request.new(URI.join(endpoint.uri, path), options)
          SiteInspector.hydra.queue(request)
        end
        SiteInspector.hydra.run
      end

      def proper_404s?
        @proper_404s ||= !path_exists?(random_path)
      end

      def to_h
        prefetch
        {
          doctype: doctype,
          generator: generator,
          sitemap_xml: sitemap_xml?,
          robots_txt: robots_txt?,
          humans_txt: humans_txt?,
          proper_404s: proper_404s?
        }
      end

      private

      def random_path
        require 'securerandom'
        @random_path ||= SecureRandom.hex
      end
    end
  end
end