sul-dlss/exhibits

# frozen_string_literal: true

module Traject
  module Macros
    # Macros for working with DOR objects
    module Dor
      def stanford_mods(method, *args, **kwargs)
        lambda do |resource, accumulator, _context|
          Array(resource.smods_rec.public_send(method, *args, **kwargs)).each do |v|
            accumulator << v
          end
        end
      end

      def resource_images_iiif_urls
        lambda do |resource, accumulator, _context|
          content_metadata = resource.public_xml.at_xpath('/publicObject/contentMetadata')
          next if content_metadata.nil?

          # Select conventional file images or virtual external ones
          images = content_metadata.xpath(
            '(resource/file[@mimetype="image/jp2"] | resource/externalFile[@mimetype="image/jp2"])'
          )
          # Allow for selection of conventional ids and fileId for virtual objects
          jp2s = images.select { |node| (node.attr('id') || node.attr('fileId') || '').end_with?('jp2') }

          jp2s.each do |v|
            # Select a virtual object druid if available or the bare druid for a conventional image object
            druid = v.attr('objectId').to_s.delete_prefix('druid:')
            druid = resource.bare_druid if druid.empty?
            accumulator << stacks_iiif_url(druid, (v.attr('id') || v.attr('fileId') || '').delete_suffix('.jp2'))
          end
        end
      end

      private

      def stacks_iiif_url(bare_druid, file_name)
        "#{Settings.stacks.iiif_url}/#{bare_druid}%2F#{ERB::Util.url_encode(file_name)}"
      end
    end
  end
end