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    * #%L
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    * %%
    * Copyright (C) 2022 wcm.io
    * %%
    * Licensed 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.
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   */
  package io.wcm.siteapi.handler.caconfig.impl.property;
  
  import java.util.Map;
  import java.util.stream.Collectors;
  
  import org.apache.commons.lang3.StringUtils;
  import org.apache.sling.api.SlingHttpServletRequest;
  import org.apache.sling.api.resource.Resource;
  import org.apache.sling.api.resource.ResourceResolver;
  import org.apache.sling.api.resource.ValueMap;
  import org.apache.sling.api.wrappers.ValueMapDecorator;
  import org.apache.sling.caconfig.spi.metadata.PropertyMetadata;
  import org.jetbrains.annotations.NotNull;
  import org.jetbrains.annotations.Nullable;
  import org.osgi.service.component.annotations.Component;
  import org.osgi.service.component.annotations.Reference;
  import org.osgi.service.component.propertytypes.ServiceRanking;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import com.day.cq.dam.api.DamConstants;
  import com.day.cq.wcm.api.NameConstants;
  import com.day.cq.wcm.api.Page;
  
  import io.wcm.handler.link.Link;
  import io.wcm.handler.link.LinkHandler;
  import io.wcm.handler.media.Media;
  import io.wcm.handler.media.MediaArgs;
  import io.wcm.handler.media.MediaComponentPropertyResolver;
  import io.wcm.handler.media.MediaHandler;
  import io.wcm.siteapi.handler.link.LinkDecoratorManager;
  import io.wcm.siteapi.handler.media.MediaDecoratorManager;
  import io.wcm.siteapi.processor.caconfig.ContextAwareConfigurationPropertyMapper;
  import io.wcm.sling.commons.adapter.AdaptTo;
  
  /**
   * Detects properties that use widgetType=pathbrowser.
   * Depending on the actual path, those are either references to content pages or assets.
   * A corresponding link or media object is resolved, and mapped to it's JSON representation.
   */
  @Component(service = ContextAwareConfigurationPropertyMapper.class)
  @ServiceRanking(-250)
  public class ContentPathPropertyMapper implements ContextAwareConfigurationPropertyMapper<Object> {
  
    // copied from io.wcm.caconfig.editor.EditorProperties to avoid direct dependency
    static final String PROPERTY_WIDGET_TYPE = "widgetType";
    static final String WIDGET_TYPE_PATHBROWSER = "pathbrowser";
  
    private static final Logger log = LoggerFactory.getLogger(ContentPathPropertyMapper.class);
  
    @Reference
    private LinkDecoratorManager linkDecoratorManager;
    @Reference
    private MediaDecoratorManager mediaDecoratorManager;
  
    @Override
    public boolean accept(@NotNull Object value,
        @NotNull PropertyMetadata<?> metadata, @NotNull SlingHttpServletRequest request) {
      Map<String, String> properties = metadata.getProperties();
      if (properties == null) {
        return false;
      }
      return StringUtils.equals(properties.get(PROPERTY_WIDGET_TYPE), WIDGET_TYPE_PATHBROWSER);
    }
  
    @Override
    public @Nullable Object map(@NotNull Object value,
        @NotNull PropertyMetadata<?> metadata, @NotNull SlingHttpServletRequest request) {
      Resource resource = getResource(value, request.getResourceResolver());
      if (resource != null) {
        if (isPage(resource)) {
          return buildPageReference(resource, request);
        }
        else if (isAsset(resource)) {
          return buildMediaReference(resource, metadata, request);
        }
      }
      return null;
    }
  
   /**
    * Check if the given path points to a valid resource.
    */
   private @Nullable Resource getResource(@NotNull Object value, @NotNull ResourceResolver resourceResolver) {
     if (value instanceof String) {
       return resourceResolver.getResource((String)value);
     }
     else {
       return null;
     }
   }
 
   /**
    * Checks if the resource is a AEM page.
    */
   private boolean isPage(@NotNull Resource resource) {
     return StringUtils.equals(resource.getResourceType(), NameConstants.NT_PAGE);
   }
 
   /**
    * Resolves a link to the page using link handler and returns the decorated reference.
    */
   private @Nullable Object buildPageReference(@NotNull Resource resource, @NotNull SlingHttpServletRequest request) {
     Page page = resource.adaptTo(Page.class);
     if (page == null) {
       return null;
     }
     LinkHandler linkHandler = AdaptTo.notNull(request, LinkHandler.class);
     Link link = linkHandler.get(page).build();
     return linkDecoratorManager.decorate(link, request.getResource());
   }
 
   /**
    * Checks if the resource is an AEM asset.
    */
   private boolean isAsset(@NotNull Resource resource) {
     return StringUtils.equals(resource.getResourceType(), DamConstants.NT_DAM_ASSET);
   }
 
   /**
    * Resolves a reference to the asset using media handler and returns the decorated reference.
    */
   private @Nullable Object buildMediaReference(@NotNull Resource resource,
       @NotNull PropertyMetadata<?> metadata, @NotNull SlingHttpServletRequest request) {
     MediaHandler mediaHandler = AdaptTo.notNull(request, MediaHandler.class);
 
     // support reading media handler component properties from metadata
     MediaArgs mediaArgs = new MediaArgs();
     Map<String, String> properties = metadata.getProperties();
     if (properties != null) {
       try (MediaComponentPropertyResolver resolver = new MediaComponentPropertyResolver(convertToValueMap(properties))) {
         mediaArgs.mediaFormatOptions(resolver.getMediaFormatOptions());
         mediaArgs.autoCrop(resolver.isAutoCrop());
         mediaArgs.imageSizes(resolver.getImageSizes());
       }
       catch (Exception ex) {
         log.warn("Unable to close MediaComponentPropertyResolver.", ex);
       }
     }
 
     Media media = mediaHandler.get(resource.getPath(), mediaArgs).build();
     return mediaDecoratorManager.decorate(media, request.getResource());
   }
 
   /**
    * Converts a map of string properties to a value map.
    * Property values separates by "," are transformed into an string array.
    * @param properties Properties
    * @return Value map
    */
   private ValueMap convertToValueMap(Map<String, String> properties) {
     return new ValueMapDecorator(properties.entrySet().stream()
         .map(entry -> Map.<String, Object>entry(entry.getKey(), StringUtils.split(entry.getValue(), ",")))
         .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)));
   }
 
 }