# mixin to provide URL for IIIF Content Search service
module IiifPrint
  module IiifManifestPresenterBehavior
    extend ActiveSupport::Concern

    # Extending the presenter to the base url which includes the protocol.
    # We need the base url to render the facet links and normalize the interface.
    attr_accessor :base_url

    def manifest_metadata
      # ensure we are using a SolrDocument
      @manifest_metadata ||= IiifPrint.manifest_metadata_from(work: model.solr_document, presenter: self)
    end

    def search_service
      Rails.application.routes.url_helpers.solr_document_iiif_search_url(id, host: hostname)
    end

    # OVERRIDE: Hyrax 3x, avoid nil returning to IIIF Manifest gem
    # @see https://github.com/samvera/iiif_manifest/blob/c408f90eba11bef908796c7236ba6bcf8d687acc/lib/iiif_manifest/v3/manifest_builder/record_property_builder.rb#L28
    ##
    # @return [Array<Hash{String => String}>]
    def sequence_rendering
      Array(try(:rendering_ids)).map do |file_set_id|
        rendering = file_set_presenters.find { |p| p.id == file_set_id }
        return [] unless rendering

        { '@id' => Hyrax::Engine.routes.url_helpers.download_url(rendering.id, host: hostname),
          'format' => rendering.mime_type.presence || I18n.t("hyrax.manifest.unknown_mime_text"),
          'label' => I18n.t("hyrax.manifest.download_text") + (rendering.label || '') }
      end.flatten
    end

    # OVERRIDE: Hyrax v3.x
    module DisplayImagePresenterBehavior
      # Extending the presenter to the base url which includes the protocol.
      # We need the base url to render the facet links and normalize the interface.
      attr_accessor :base_url

      # Extending this class because there is an #ability= but not #ability and this definition
      # mirrors the Hyrax::IiifManifestPresenter#ability.
      def ability
        @ability ||= NullAbility.new
      end

      def display_image
        return nil unless latest_file_id
        return nil unless model.image?
        return nil unless IiifPrint.config.default_iiif_manifest_version == 2

        IIIFManifest::DisplayImage
          .new(display_image_url(hostname),
            format: image_format(alpha_channels),
            width: width,
            height: height,
            iiif_endpoint: iiif_endpoint(latest_file_id, base_url: hostname))
      end

      # OVERRIDE: IIIF Hyrax AV v0.2 #display_content for prez 3 manifests
      def display_content
        return nil unless latest_file_id
        return super unless model.image?

        IIIFManifest::V3::DisplayContent
          .new(display_image_url(hostname),
            format: image_format(alpha_channels),
            width: width,
            height: height,
            type: 'Image',
            iiif_endpoint: iiif_endpoint(latest_file_id, base_url: hostname))
      end

      def display_image_url(base_url)
        if ENV['EXTERNAL_IIIF_URL'].present?
          # At the moment we are only concerned about Hyrax's default image url builder
          iiif_image_url_builder(url_builder: Hyrax.config.iiif_image_url_builder)
        else
          super
        end
      end

      def iiif_endpoint(file_id, base_url: request.base_url)
        if ENV['EXTERNAL_IIIF_URL'].present?
          IIIFManifest::IIIFEndpoint.new(
            File.join(ENV['EXTERNAL_IIIF_URL'], file_id),
            profile: Hyrax.config.iiif_image_compliance_level_uri
          )
        else
          super
        end
      end

      def hostname
        @hostname || 'localhost'
      end

      ##
      # @return [Boolean] false
      def work?
        false
      end

      private

      def latest_file_id
        if ENV['EXTERNAL_IIIF_URL'].present?
          external_latest_file_id
        else
          super
        end
      end

      def external_latest_file_id
        @latest_file_id ||= digest_sha1
      end

      def iiif_image_url_builder(url_builder:)
        args = [
          latest_file_id,
          ENV['EXTERNAL_IIIF_URL'],
          Hyrax.config.iiif_image_size_default
        ]
        # In Hyrax 3, Hyrax.config.iiif_image_url_builder takes an additional argument
        args << image_format(alpha_channels) if url_builder.arity == 4

        url_builder.call(*args).gsub(%r{images/}, '')
      end
    end
  end
end