# frozen_string_literal: true

module Cocina
  module Models
    module Mapping
      module Normalizers
        module Mods
          # Normalizes a Fedora MODS document for originInfo elements.
          # Must be called after authorityURI attribs are normalized
          class OriginInfoNormalizer
            DATE_FIELDS = %w[dateIssued copyrightDate dateCreated dateCaptured dateValid dateOther dateModified].freeze

            # @param [Nokogiri::Document] mods_ng_xml MODS to be normalized
            # @return [Nokogiri::Document] normalized MODS
            def self.normalize(mods_ng_xml:)
              new(mods_ng_xml: mods_ng_xml).normalize
            end

            def initialize(mods_ng_xml:)
              @ng_xml = mods_ng_xml.dup
              @ng_xml.encoding = 'UTF-8'
            end

            def normalize
              remove_empty_child_elements
              remove_empty_origin_info # must be after remove_empty_child_elements
              normalize_legacy_mods_event_type
              place_term_type_normalization
              place_term_authority_normalization # must be after place_term_type_normalization
              normalize_authority_marcountry
              single_key_date
              remove_trailing_period_from_date_values
              ng_xml
            end

            private

            attr_reader :ng_xml

            # must be called before remove_empty_origin_info
            def remove_empty_child_elements
              ng_xml.root.xpath('//mods:originInfo/mods:*', mods: ModsNormalizer::MODS_NS).each do |child_node|
                # if a node has either of these 2 attributes, it could have meaning even without any content
                next if child_node.xpath('.//*[@valueURI]').present?
                next if child_node.xpath('.//*[@xlink:href]', xlink: ModsNormalizer::XLINK_NS).present?

                child_node.remove if child_node.content.blank?
              end
            end

            # must be called after remove_empty_child_elements
            def remove_empty_origin_info
              ng_xml.root.xpath('//mods:originInfo[not(mods:*) and not(@*)]', mods: ModsNormalizer::MODS_NS).each(&:remove)
              # make sure we remove ones such as <originInfo eventType="publication"/>
              ng_xml.root.xpath('//mods:originInfo[not(mods:*) and not(text()[normalize-space()])]', mods: ModsNormalizer::MODS_NS).each(&:remove)
            end

            LEGACY_EVENT_TYPES_2_TYPE = Cocina::Models::Mapping::FromMods::Event::LEGACY_EVENT_TYPES_2_TYPE

            # because eventType is a relatively new addition to the MODS schema, records converted from MARC to MODS prior
            #   to its introduction used displayLabel as a stopgap measure, with certain values
            # The same values were also sometimes used as eventType values themselves, and will be converted to our preferred vocab.
            def normalize_legacy_mods_event_type
              ng_xml.root.xpath('//mods:originInfo[@*]', mods: ModsNormalizer::MODS_NS).each do |origin_info_node|
                event_type = origin_info_node['eventType']
                event_type = origin_info_node['displayLabel'] if event_type.blank? &&
                                                                 LEGACY_EVENT_TYPES_2_TYPE.key?(origin_info_node['displayLabel'])
                event_type = LEGACY_EVENT_TYPES_2_TYPE[event_type] if LEGACY_EVENT_TYPES_2_TYPE.key?(event_type)

                origin_info_node['eventType'] = event_type if event_type.present?
                origin_info_node.delete('displayLabel') if event_type.present? &&
                                                           event_type == LEGACY_EVENT_TYPES_2_TYPE[origin_info_node['displayLabel']]
              end
            end

            # must be called before place_term_authority_normalization
            # if the cocina model doesn't have a code, then it will have a value;
            #   this is output as attribute type=text on the roundtripped placeTerm element
            def place_term_type_normalization
              ng_xml.root.xpath('//mods:originInfo/mods:place/mods:placeTerm', mods: ModsNormalizer::MODS_NS).each do |place_term_node|
                next if place_term_node.content.blank?

                place_term_node['type'] = 'text' if place_term_node.attributes['type'].blank?
              end
            end

            # must be called after place_term_type_normalization
            # if the MODS has a single place element with both text and code placeTerm elements, if the text
            # element has no authority attributes but the code element DOES have authority attributes, then both
            # the text and the code elements get the authority attributes from the code element.
            def place_term_authority_normalization
              ng_xml.root.xpath('//mods:originInfo/mods:place[mods:placeTerm/@type]', mods: ModsNormalizer::MODS_NS).each do |place_node|
                text_place_term_node = place_node.xpath("mods:placeTerm[not(@type='code')]", mods: ModsNormalizer::MODS_NS).first
                next unless text_place_term_node
                next if text_place_term_node.text.blank?

                code_place_term_node = place_node.xpath("mods:placeTerm[@type='code']", mods: ModsNormalizer::MODS_NS).first
                next unless code_place_term_node
                next if code_place_term_node.text.blank?

                text_authority_attributes = authority_attributes(text_place_term_node)
                code_authority_attributes = authority_attributes(code_place_term_node)

                # NOTE: deliberately skipping situation where text node has some authority info and code node
                #  has other authority info as we may never encounter this

                if text_authority_attributes.present? && code_authority_attributes.blank?
                  text_authority_attributes.each do |key, val|
                    code_place_term_node[key] = val
                  end
                  next
                end

                next if code_authority_attributes.blank? || text_authority_attributes.present?

                code_authority_attributes.each do |key, val|
                  text_place_term_node[key] = val
                end
              end
            end

            def authority_attributes(ng_node)
              {
                valueURI: ng_node['valueURI'],
                authority: ng_node['authority'],
                authorityURI: ng_node['authorityURI']
              }.compact
            end

            def normalize_authority_marcountry
              ng_xml.root.xpath("//mods:*[@authority='marcountry']", mods: ModsNormalizer::MODS_NS).each do |node|
                node[:authority] = 'marccountry'
              end
            end

            def single_key_date
              DATE_FIELDS.each do |date_field|
                key_date_nodes = ng_xml.root.xpath("//mods:originInfo/mods:#{date_field}[@point and @keyDate='yes']", mods: ModsNormalizer::MODS_NS)
                next unless key_date_nodes.size == 2

                end_node = key_date_nodes.find { |node| node['point'] == 'end' }
                end_node.delete('keyDate') if end_node && end_node['keyDate'].present?
              end
            end

            def remove_trailing_period_from_date_values
              DATE_FIELDS.each do |date_field|
                ng_xml.root.xpath("//mods:originInfo/mods:#{date_field}", mods: ModsNormalizer::MODS_NS)
                      .each { |date_node| date_node.content = date_node.content.delete_suffix('.') }
              end
            end
          end
        end
      end
    end
  end
end