.nested_field
  - if f.object.new_record?
    = f.input :document_type, as: :hidden, input_html: { value: controller_name.singularize }
    = #f.input :name
    = f.input :attachment
  - else
    .controls
      .attachment_part
        .attachment_entry
          .attachment_entry_content
            .attachment_entry_image      
              = link_to document_image_tag(f.object), download_document_path(f.object)
            .attachment_entry_description
              .file_name_part
                = link_to f.object.attachment_file_name, download_document_path(f.object)
              .file_size_part
                = number_to_human_size f.object.attachment_file_size


  = link_to_remove_fields t("remove"), f