content: /*
   *  Licensed to the Apache Software Foundation (ASF) under one
   *  or more contributor license agreements.  See the NOTICE file
   *  distributed with this work for additional information
   *  regarding copyright ownership.  The ASF licenses this file
   *  to you under the Apache License, Version 2.0 (the
   *  "License"); you may not use this file except in compliance
   *  with the License.  You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License.
   */
  package org.apache.causeway.viewer.wicket.ui.components.attributes.image;
  
  import java.awt.image.BufferedImage;
  import java.util.List;
  import java.util.Optional;
  
  import org.apache.wicket.Component;
  import org.apache.wicket.markup.html.form.FormComponent;
  import org.apache.wicket.markup.html.form.upload.FileUpload;
  import org.apache.wicket.model.IModel;
  
  import org.apache.causeway.applib.services.placeholder.PlaceholderRenderService.PlaceholderLiteral;
  import org.apache.causeway.viewer.commons.model.components.UiString;
  import org.apache.causeway.viewer.wicket.model.models.FileUploadModels;
  import org.apache.causeway.viewer.wicket.model.models.UiAttributeWkt;
  import org.apache.causeway.viewer.wicket.ui.components.attributes.AttributeFragmentFactory.InputFragment;
  import org.apache.causeway.viewer.wicket.ui.components.attributes.AttributePanelWithFormField;
  import org.apache.causeway.viewer.wicket.ui.util.Wkt;
  
  /**
   * Panel for rendering scalars of type {@link BufferedImage}.
   */
  class ImageAttributePanel
  extends AttributePanelWithFormField<BufferedImage> {
  
      private static final long serialVersionUID = 1L;
  
      public ImageAttributePanel(final String id, final UiAttributeWkt attributeModel) {
          super(id, attributeModel, BufferedImage.class);
      }
  
      protected IModel<List<FileUpload>> fileUploadModel() {
          return FileUploadModels.image(attributeModel());
      }
  
      // -- INPUT FORMAT
  
      @Override
      protected Optional<InputFragment> getInputFragmentType() {
          return Optional.of(InputFragment.FILE);
      }
  
      // generic type mismatch; no issue as long as we don't use conversion
      @SuppressWarnings({ "unchecked", "rawtypes" })
      @Override
      protected FormComponent createFormComponent(final String id, final UiAttributeWkt attributeModel) {
          var initialCaption = outputFormatAsString();
          var fileUploadField = Wkt.fileUploadField(id, initialCaption, fileUploadModel());
          addAcceptFilterTo(fileUploadField);
          return fileUploadField;
      }
  
      // -- OUTPUT FORMAT
  
      @Override
      protected UiString obtainOutputFormat() {
          var caption = pojoOptional()
                  .map(buffImg->"Image")
                  .orElseGet(()->
                      getPlaceholderRenderService()
                      .asText(PlaceholderLiteral.NULL_REPRESENTATION));
          return UiString.text(caption);
      }
  
      @Override
      protected Component createComponentForOutput(final String id) {
          return new ImagePanel(id, attributeModel());
      }
  
      // -- HELPER
  
      private void addAcceptFilterTo(final Component component){
          Wkt.attributeReplace(component, "accept", attributeModel().getFileAccept());
      }
  
      private Optional<BufferedImage> pojoOptional() {
          return Optional.ofNullable(attributeModel().unwrapAs(type));
      }
  
  }
  