/*
    * 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.chemistry.opencmis.client.bindings.spi.atompub;
  
  import java.math.BigInteger;
  import java.util.ArrayList;
  
  import org.apache.chemistry.opencmis.client.bindings.spi.BindingSession;
  import org.apache.chemistry.opencmis.client.bindings.spi.atompub.objects.AtomElement;
  import org.apache.chemistry.opencmis.client.bindings.spi.atompub.objects.AtomEntry;
  import org.apache.chemistry.opencmis.client.bindings.spi.atompub.objects.AtomFeed;
  import org.apache.chemistry.opencmis.client.bindings.spi.atompub.objects.AtomLink;
  import org.apache.chemistry.opencmis.client.bindings.spi.http.Response;
  import org.apache.chemistry.opencmis.commons.data.ExtensionsData;
  import org.apache.chemistry.opencmis.commons.data.ObjectData;
  import org.apache.chemistry.opencmis.commons.data.ObjectList;
  import org.apache.chemistry.opencmis.commons.enums.RelationshipDirection;
  import org.apache.chemistry.opencmis.commons.impl.Constants;
  import org.apache.chemistry.opencmis.commons.impl.UrlBuilder;
  import org.apache.chemistry.opencmis.commons.impl.dataobjects.ObjectListImpl;
  import org.apache.chemistry.opencmis.commons.spi.RelationshipService;
  
  /**
   * Relationship Service AtomPub client.
   */
  public class RelationshipServiceImpl extends AbstractAtomPubService implements RelationshipService {
  
      /**
       * Constructor.
       */
      public RelationshipServiceImpl(BindingSession session) {
          setSession(session);
      }
  
      @Override
      public ObjectList getObjectRelationships(String repositoryId, String objectId, Boolean includeSubRelationshipTypes,
              RelationshipDirection relationshipDirection, String typeId, String filter, Boolean includeAllowableActions,
              BigInteger maxItems, BigInteger skipCount, ExtensionsData extension) {
          ObjectListImpl result = new ObjectListImpl();
  
          // find the link
          String link = loadLink(repositoryId, objectId, Constants.REL_RELATIONSHIPS, Constants.MEDIATYPE_FEED);
  
          if (link == null) {
              throwLinkException(repositoryId, objectId, Constants.REL_RELATIONSHIPS, Constants.MEDIATYPE_FEED);
          }
  
          UrlBuilder url = new UrlBuilder(link);
          url.addParameter(Constants.PARAM_SUB_RELATIONSHIP_TYPES, includeSubRelationshipTypes);
          url.addParameter(Constants.PARAM_RELATIONSHIP_DIRECTION, relationshipDirection);
          url.addParameter(Constants.PARAM_TYPE_ID, typeId);
          url.addParameter(Constants.PARAM_FILTER, filter);
          url.addParameter(Constants.PARAM_ALLOWABLE_ACTIONS, includeAllowableActions);
          url.addParameter(Constants.PARAM_MAX_ITEMS, maxItems);
          url.addParameter(Constants.PARAM_SKIP_COUNT, skipCount);
  
          // read and parse
          Response resp = read(url);
          AtomFeed feed = parse(resp.getStream(), AtomFeed.class);
  
          // handle top level
          for (AtomElement element : feed.getElements()) {
              if (element.getObject() instanceof AtomLink) {
                  if (isNextLink(element)) {
                      result.setHasMoreItems(Boolean.TRUE);
                  }
              } else if (isInt(NAME_NUM_ITEMS, element)) {
                  result.setNumItems((BigInteger) element.getObject());
              }
          }
  
          // get the children
          if (!feed.getEntries().isEmpty()) {
              result.setObjects(new ArrayList<ObjectData>(feed.getEntries().size()));
  
              for (AtomEntry entry : feed.getEntries()) {
                  ObjectData relationship = null;
  
                  lockLinks();
                  try {
                      // clean up cache
                      removeLinks(repositoryId, entry.getId());
  
                     // walk through the entry
                     for (AtomElement element : entry.getElements()) {
                         if (element.getObject() instanceof AtomLink) {
                             addLink(repositoryId, entry.getId(), (AtomLink) element.getObject());
                         } else if (element.getObject() instanceof ObjectData) {
                             relationship = (ObjectData) element.getObject();
                         }
                     }
                 } finally {
                     unlockLinks();
                 }
 
                 if (relationship != null) {
                     result.getObjects().add(relationship);
                 }
             }
 
         }
 
         return result;
     }
 }