module Hyrax
  module IndexesThumbnails
    extend ActiveSupport::Concern

    included do
      class_attribute :thumbnail_path_service
      self.thumbnail_path_service = ThumbnailPathService
      class_attribute :thumbnail_field
      self.thumbnail_field = 'thumbnail_path_ss'.freeze
    end

    # Adds thumbnail indexing to the solr document
    def generate_solr_document
      super.tap do |solr_doc|
        index_thumbnails(solr_doc)
      end
    end

    # Write the thumbnail paths into the solr_document
    # @param [Hash] solr_document the solr document to add the field to
    def index_thumbnails(solr_document)
      solr_document[thumbnail_field] = thumbnail_path
    end

    # Returns the value for the thumbnail path to put into the solr document
    def thumbnail_path
      self.class.thumbnail_path_service.call(object)
    end
  end
end