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.pages.common.bootstrap.css;
  
  import java.util.Locale;
  
  import org.apache.wicket.Application;
  import org.apache.wicket.markup.head.CssHeaderItem;
  import org.apache.wicket.markup.head.IHeaderResponse;
  import org.apache.wicket.request.resource.CssResourceReference;
  import org.apache.wicket.request.resource.PackageResource;
  import org.apache.wicket.request.resource.ResourceReference;
  
  import lombok.Getter;
  import lombok.experimental.Accessors;
  
  import de.agilecoders.wicket.core.Bootstrap;
  import de.agilecoders.wicket.core.settings.IBootstrapSettings;
  import de.agilecoders.wicket.core.settings.ITheme;
  
  /**
   * A CSS resource reference that provides CSS rules which override the CSS rules
   * provided by the currently active Bootstrap theme.
   * Usually the overrides rules are about sizes and weights, but should not change any colors
   */
  public class BootstrapOverridesCssResourceReference extends CssResourceReference {
  
      private static final long serialVersionUID = 1L;
  
      @Getter(lazy = true) @Accessors(fluent = true)
      private static final BootstrapOverridesCssResourceReference instance =
          new BootstrapOverridesCssResourceReference();
  
      public static CssHeaderItem asHeaderItem() {
          return CssHeaderItem.forReference(BootstrapOverridesCssResourceReference.instance());
      }
  
      private BootstrapOverridesCssResourceReference() {
          super(BootstrapOverridesCssResourceReference.class, "bootstrap-overrides-all-v2.css");
      }
  
      /**
       * Contributes theme specific Bootstrap CSS overrides if there is such resource
       *
       * @param response The header response to contribute to
       */
      public static void contributeThemeSpecificOverrides(
              final Application application,
              final IHeaderResponse response) {
  
          final IBootstrapSettings bootstrapSettings = Bootstrap.getSettings(application);
  
          final ITheme activeTheme = bootstrapSettings.getActiveThemeProvider().getActiveTheme();
          final String name = activeTheme.name().toLowerCase(Locale.ENGLISH);
          final String themeSpecificOverride = "bootstrap-overrides-" + name + ".css";
          final ResourceReference.Key themeSpecificOverrideKey =
                  new ResourceReference.Key(BootstrapOverridesCssResourceReference.class.getName(),
                          themeSpecificOverride, null, null, null);
          if (PackageResource.exists(themeSpecificOverrideKey)) {
              response.render(CssHeaderItem.forReference(new CssResourceReference(themeSpecificOverrideKey)));
          }
      }
  
  }
  