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.about;
  
  import java.io.InputStream;
  
  import jakarta.inject.Inject;
  import jakarta.inject.Provider;
  import jakarta.servlet.ServletContext;
  
  import org.apache.wicket.markup.html.basic.Label;
  import org.apache.wicket.model.IModel;
  import org.apache.wicket.model.LambdaModel;
  
  import org.apache.causeway.commons.internal.base._NullSafe;
  import org.apache.causeway.core.config.CausewayConfiguration;
  import org.apache.causeway.viewer.wicket.model.models.AboutModel;
  import org.apache.causeway.viewer.wicket.ui.pages.home.HomePage;
  import org.apache.causeway.viewer.wicket.ui.panels.PanelAbstract;
  
  /**
   * {@link PanelAbstract Panel} displaying welcome message (as used on
   * {@link HomePage}).
   */
  class AboutPanel
  extends PanelAbstract<CausewayConfiguration.Viewer.Common.Application, AboutModel> {
  
      private static final long serialVersionUID = 1L;
  
      private static final String ID_MANIFEST_ATTRIBUTES = "manifestAttributes";
      private static final String ID_APPLICATION_NAME = "applicationName";
      private static final String ID_APPLICATION_VERSION = "applicationVersion";
      private static final String ID_ABOUT_MESSAGE = "aboutMessage";
  
      public static class LabelVisibleOnlyIfNonEmpty extends Label {
  
          private static final long serialVersionUID = 1L;
          private final IModel<String> label;
  
          public LabelVisibleOnlyIfNonEmpty(final String id, final IModel<String> label) {
              super(id, label);
              this.label = label;
          }
  
          @Override protected void onConfigure() {
              super.onConfigure();
              setVisibilityAllowed(label != null && !_NullSafe.isEmpty(label.getObject()));
          }
      }
  
      @Inject
      private ServletContext servletContext;
  
      private JarManifestModel jarManifestModel;
  
      public AboutPanel(final String id, final AboutModel aboutModel) {
          super(id);
  
          add(new LabelVisibleOnlyIfNonEmpty(ID_APPLICATION_NAME, LambdaModel.of(()->aboutModel.getObject().getName())));
          add(new LabelVisibleOnlyIfNonEmpty(ID_APPLICATION_VERSION, LambdaModel.of(()->aboutModel.getObject().getVersion())));
          add(new LabelVisibleOnlyIfNonEmpty(ID_ABOUT_MESSAGE, LambdaModel.of(()->aboutModel.getObject().getAbout())));
  
          if(jarManifestModel == null) {
              Provider<InputStream> metaInfManifestProvider =
                      () -> servletContext.getResourceAsStream("/META-INF/MANIFEST.MF");
              jarManifestModel = new JarManifestModel(metaInfManifestProvider);
          }
  
          add(new JarManifestPanel(ID_MANIFEST_ATTRIBUTES, jarManifestModel));
      }
  
  }
  