/**
    * This file Copyright (c) 2017 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.rest.reference.jcr;
  
  import info.magnolia.context.Context;
  import info.magnolia.jcr.util.PropertyUtil;
  import info.magnolia.rest.delivery.jcr.decorator.ReadOnlyNode;
  import info.magnolia.rest.reference.ReferenceResolver;
  import info.magnolia.rest.reference.ReferenceResolverDefinition;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  import java.util.Optional;
  
  import javax.inject.Inject;
  import javax.inject.Provider;
  import javax.jcr.Node;
  import javax.jcr.Property;
  import javax.jcr.RepositoryException;
  import javax.jcr.Session;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * The implementation of {@link info.magnolia.rest.reference.ReferenceResolver}, expands UUID or list of UUIDs to node.
   */
  public class UuidReferenceResolver implements ReferenceResolver<Property, Node> {
  
      private static final Logger log = LoggerFactory.getLogger(UuidReferenceResolver.class);
      private final Provider<Context> contextProvider;
      private final ReferenceResolverDefinition definition;
  
      @Inject
      public UuidReferenceResolver(Provider<Context> contextProvider, ReferenceResolverDefinition definition) {
          this.contextProvider = contextProvider;
          this.definition = definition;
      }
  
      @Override
      public Optional<Node> resolve(Property item) {
          try {
              Session session = contextProvider.get().getJCRSession(definition.getTargetWorkspace());
              if (item.isMultiple() && item.getValues() != null) {
                  List<Node> nodes = new ArrayList<>();
                  for (String uuid : PropertyUtil.getValuesStringList(item.getValues())) {
                      nodes.add(session.getNodeByIdentifier(uuid));
                  }
  
                  return Optional.of(new ReadOnlyNode(item.getName(), item.getParent(), nodes, Collections.emptyList()));
              }
  
              return Optional.of(session.getNodeByIdentifier(item.getString()));
          } catch (RepositoryException e) {
              log.warn("Error on resolving item {}", item, e);
          }
  
          return Optional.empty();
      }
  }