def prepare_instance_variables_for_batch_control_display
        # set up some parameters for allowing the batch controls to show appropriately
        max_batch_size = 80
        count_on_page = @document_list.count { |doc| batch.index(doc.id) }
        @disable_select_all = @document_list.count > max_batch_size
        @result_set_size = @response.response["numFound"]
        @empty_batch = batch.empty?
        @all_checked = (count_on_page == @document_list.count)
        @add_works_to_collection = params.fetch(:add_works_to_collection, '')
        @add_works_to_collection_label = params.fetch(:add_works_to_collection_label, '')
      end
def prepare_instance_variables_for_batch_control_display
        # set up some parameters for allowing the batch controls to show appropriately
        max_batch_size = 80
        count_on_page = @document_list.count { |doc| batch.index(doc.id) }
        @disable_select_all = @document_list.count > max_batch_size
        @result_set_size = @response.response["numFound"]
        @empty_batch = batch.empty?
        @all_checked = (count_on_page == @document_list.count)
        @add_works_to_collection = params.fetch(:add_works_to_collection, '')
        @add_works_to_collection_label = params.fetch(:add_works_to_collection_label, '')
      end
TODO: Extract a presenter object that wrangles all of these instance variables.