module Docs
  class Http
    class EntriesFilter < Docs::EntriesFilter
      def get_name
        name = at_css('h1').content
        name.remove! %r{\A.+\:}
        name.remove! %r{\A.+\-\-}
        "#{rfc}: #{name.strip}"
      end

      def get_type
        'RFC'
      end

      def rfc
        slug.sub('rfc', 'RFC ')
      end

      SECTIONS = {
        'rfc2616' => [
          [3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15],
          [14],
          []
        ],
        'rfc4918' => [
          [],
          [11],
          []
        ],
        'rfc7230' => [
          (2..9).to_a,
          [],
          []
        ],
        'rfc7231' => [
          [3, 8, 9],
          [],
          [4, 5, 6, 7]
        ],
        'rfc7232' => [
          [5, 6, 7, 8],
          [2, 3, 4],
          []
        ],
        'rfc7233' => [
          [5, 6],
          [2, 3, 4],
          []
        ],
        'rfc7234' => [
          [3, 6, 7, 8],
          [4, 5],
          []
        ],
        'rfc7235' => [
          [2, 5, 6],
          [3, 4],
          []
        ]
      }

      LEVEL_1 = /\A(\d+)\z/
      LEVEL_2 = /\A(\d+)\.\d+\z/
      LEVEL_3 = /\A(\d+)\.\d+\.\d+\z/

      def additional_entries
        return [] if root_page?
        type = nil

        css('a[href^="#section-"]').each_with_object([]) do |node, entries|
          id = node['href'].remove('#')
          break entries if entries.any? { |e| e[1] == id }

          content = node.next.content.strip
          content.remove! %r{\s*\.+\d*\z}
          content.remove! %r{\A[\.\s]+}

          name = "#{content} (#{rfc})"
          number = node.content.strip

          if number =~ LEVEL_1
            if SECTIONS[slug][0].include?($1.to_i)
              entries << [name, id, self.name]
            end

            type = content.sub(/\ Definitions\z/, 's')
            type = 'Request Header Fields' if type.include?('Header Fields') && type.exclude?('Response')
            type = 'Response Status Codes' if type.include?('Status Codes')
            type = self.name unless type.start_with?('Request ') || type.start_with?('Response ')
          elsif (number =~ LEVEL_2 && SECTIONS[slug][1].include?($1.to_i)) ||
                (number =~ LEVEL_3 && SECTIONS[slug][2].include?($1.to_i))
            entries << [name, id, (name =~ /\A\d\d\d/ ? 'Response Status Codes' : type )]
          end
        end
      end
    end
  end
end