/*
    * 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.server.impl.atompub;
  
  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.exceptions.CmisRuntimeException;
  import org.apache.chemistry.opencmis.commons.impl.Constants;
  import org.apache.chemistry.opencmis.commons.impl.UrlBuilder;
  import org.apache.chemistry.opencmis.commons.server.CallContext;
  import org.apache.chemistry.opencmis.commons.server.CmisService;
  import org.apache.chemistry.opencmis.commons.server.ObjectInfo;
  import static org.apache.chemistry.opencmis.server.impl.atompub.AtomPubUtils.RESOURCE_RELATIONSHIPS;
  import static org.apache.chemistry.opencmis.server.impl.atompub.AtomPubUtils.compileBaseUrl;
  import static org.apache.chemistry.opencmis.server.impl.atompub.AtomPubUtils.compileUrl;
  import static org.apache.chemistry.opencmis.server.impl.atompub.AtomPubUtils.compileUrlBuilder;
  import static org.apache.chemistry.opencmis.server.impl.atompub.AtomPubUtils.writeObjectEntry;
  import static org.apache.chemistry.opencmis.server.shared.HttpUtils.getBigIntegerParameter;
  import static org.apache.chemistry.opencmis.server.shared.HttpUtils.getBooleanParameter;
  import static org.apache.chemistry.opencmis.server.shared.HttpUtils.getEnumParameter;
  import static org.apache.chemistry.opencmis.server.shared.HttpUtils.getStringParameter;
  
  import java.math.BigInteger;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  
  /**
   * Relationship Service operations.
   */
  public class RelationshipService
  {
      private RelationshipService(  )
      {
      }
  
      /**
       * Get object relationships.
       */
      public static void getObjectRelationships( CallContext context, CmisService service, String repositoryId,
          HttpServletRequest request, HttpServletResponse response )
          throws Exception
      {
          // get parameters
          String objectId = getStringParameter( request, Constants.PARAM_ID );
          Boolean includeSubRelationshipTypes = getBooleanParameter( request, Constants.PARAM_SUB_RELATIONSHIP_TYPES );
          RelationshipDirection relationshipDirection = getEnumParameter( request,
                  Constants.PARAM_RELATIONSHIP_DIRECTION, RelationshipDirection.class );
          String typeId = getStringParameter( request, Constants.PARAM_TYPE_ID );
          String filter = getStringParameter( request, Constants.PARAM_FILTER );
          Boolean includeAllowableActions = getBooleanParameter( request, Constants.PARAM_ALLOWABLE_ACTIONS );
          BigInteger maxItems = getBigIntegerParameter( request, Constants.PARAM_MAX_ITEMS );
          BigInteger skipCount = getBigIntegerParameter( request, Constants.PARAM_SKIP_COUNT );
  
          // execute
          ObjectList relationships = service.getObjectRelationships( repositoryId, objectId, includeSubRelationshipTypes,
                  relationshipDirection, typeId, filter, includeAllowableActions, maxItems, skipCount, null );
  
          if ( relationships == null )
          {
              throw new CmisRuntimeException( "Relationships are null!" );
          }
  
          ObjectInfo objectInfo = service.getObjectInfo( repositoryId, objectId );
  
          if ( objectInfo == null )
          {
              throw new CmisRuntimeException( "Object Info is missing!" );
          }
  
          // set headers
          response.setStatus( HttpServletResponse.SC_OK );
          response.setContentType( Constants.MEDIATYPE_FEED );
  
          // write XML
          AtomFeed feed = new AtomFeed(  );
          feed.startDocument( response.getOutputStream(  ) );
          feed.startFeed( true );
  
          // write basic Atom feed elements
          feed.writeFeedElements( objectInfo.getId(  ), objectInfo.getCreatedBy(  ), objectInfo.getName(  ),
             objectInfo.getLastModificationDate(  ), null, relationships.getNumItems(  ) );
 
         // write links
         UrlBuilder baseUrl = compileBaseUrl( request, repositoryId );
 
         feed.writeServiceLink( baseUrl.toString(  ), repositoryId );
 
         feed.writeSelfLink( compileUrl( baseUrl, RESOURCE_RELATIONSHIPS, objectInfo.getId(  ) ), null );
 
         UrlBuilder pagingUrl = new UrlBuilder( compileUrlBuilder( baseUrl, RESOURCE_RELATIONSHIPS, objectInfo.getId(  ) ) );
         pagingUrl.addParameter( Constants.PARAM_SUB_RELATIONSHIP_TYPES, includeSubRelationshipTypes );
         pagingUrl.addParameter( Constants.PARAM_RELATIONSHIP_DIRECTION, relationshipDirection );
         pagingUrl.addParameter( Constants.PARAM_TYPE_ID, typeId );
         pagingUrl.addParameter( Constants.PARAM_FILTER, filter );
         pagingUrl.addParameter( Constants.PARAM_ALLOWABLE_ACTIONS, includeAllowableActions );
         feed.writePagingLinks( pagingUrl, maxItems, skipCount, relationships.getNumItems(  ),
             relationships.hasMoreItems(  ), AtomPubUtils.PAGE_SIZE );
 
         // write entries
         AtomEntry entry = new AtomEntry( feed.getWriter(  ) );
 
         for ( ObjectData object : relationships.getObjects(  ) )
         {
             if ( object == null )
             {
                 continue;
             }
 
             writeObjectEntry( service, entry, object, null, repositoryId, null, null, baseUrl, false );
         }
 
         // we are done
         feed.endFeed(  );
         feed.endDocument(  );
     }
 }