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.widgets.themepicker;
  
  import java.util.Collections;
  import java.util.List;
  import java.util.Map;
  import java.util.stream.Collectors;
  
  import org.apache.wicket.util.string.Strings;
  
  import org.apache.causeway.commons.collections.Can;
  import org.apache.causeway.commons.internal.collections._Lists;
  import org.apache.causeway.commons.internal.collections._Maps;
  
  import lombok.RequiredArgsConstructor;
  import lombok.extern.log4j.Log4j2;
  
  import de.agilecoders.wicket.core.settings.ITheme;
  import de.agilecoders.wicket.core.settings.ThemeProvider;
  
  /**
   *
   * @since 2.0
   *
   */
  @RequiredArgsConstructor(staticName = "of") @Log4j2
  public class ThemeProviderComposite implements ThemeProvider {
  
      private final Can<ThemeProvider> themeProviders;
  
      private ITheme defaultTheme;
      private Map<String, ITheme> themesByName;
      private List<String> availableNames;
      private List<ITheme> availableThemes;
  
      @Override
      public ITheme byName(String name) {
          if (!Strings.isEmpty(name)) {
              ensureInit();
              var theme = themesByName.get(name.toLowerCase());
              if(theme!=null) {
                  return theme;
              }
          }
  
          log.warn("'{}' theme not found amoung providers {} provinding {}, "
                  + "using default '{}' instead",
                  name,
                  themeProviders.toList(),
                  available().stream().map(ITheme::name).collect(Collectors.joining(", ")),
                  defaultTheme().name());
  
          return defaultTheme();
      }
  
      @Override
      public List<ITheme> available() {
          ensureInit();
          return availableThemes;
      }
  
      @Override
      public ITheme defaultTheme() {
          ensureInit();
          return defaultTheme;
      }
  
      public List<String> availableNames() {
          ensureInit();
          return availableNames;
      }
  
      // -- HELPER
  
      private void ensureInit() {
          if(themesByName!=null) {
              return;
          }
          themesByName = _Maps.newLinkedHashMap();
          themeProviders.forEach(themeProvider->{
  
              if(defaultTheme==null) {
                  defaultTheme = themeProvider.defaultTheme();
              }
  
              themeProvider.available().forEach(theme->{
                  themesByName.put(theme.name().toLowerCase(), theme);
              });
  
          });
          availableThemes = Collections.unmodifiableList(_Lists.newArrayList(themesByName.values()));
          availableNames = Collections.unmodifiableList(_Lists.map(availableThemes, ITheme::name));
      }
  
  }
  