/*
    *  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.directory.server.dns.store.jndi.operations;
  
  
  import java.util.HashSet;
  import java.util.Set;
  
  import javax.naming.Name;
  import javax.naming.NamingEnumeration;
  import javax.naming.NamingException;
  import javax.naming.directory.Attribute;
  import javax.naming.directory.Attributes;
  import javax.naming.directory.BasicAttribute;
  import javax.naming.directory.BasicAttributes;
  import javax.naming.directory.DirContext;
  import javax.naming.directory.SearchResult;
  
  import org.apache.directory.server.dns.messages.QuestionRecord;
  import org.apache.directory.server.dns.messages.RecordClass;
  import org.apache.directory.server.dns.messages.RecordType;
  import org.apache.directory.server.dns.messages.ResourceRecord;
  import org.apache.directory.server.dns.messages.ResourceRecordModifier;
  import org.apache.directory.server.dns.store.DnsAttribute;
  import org.apache.directory.server.dns.store.jndi.DnsOperation;
  
  
  /**
   * A JNDI context operation for looking up a Resource Record with flat attributes.
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class GetFlatRecord implements DnsOperation
  {
      /** The name of the question to get. */
      private final QuestionRecord question;
  
  
      /**
       * Creates the action to be used against the embedded JNDI provider.
       * 
       * @param question 
       */
      public GetFlatRecord( QuestionRecord question )
      {
          this.question = question;
      }
  
  
      /**
       * Note that the base is a relative path from the exiting context.
       * It is not a Dn.
       */
      public Set<ResourceRecord> execute( DirContext ctx, Name base ) throws Exception
      {
          if ( question == null )
          {
              return null;
          }
  
          Attributes matchAttrs = new BasicAttributes( true );
  
          matchAttrs.put( new BasicAttribute( DnsAttribute.NAME, question.getDomainName() ) );
          matchAttrs.put( new BasicAttribute( DnsAttribute.TYPE, question.getRecordType().name() ) );
          matchAttrs.put( new BasicAttribute( DnsAttribute.CLASS, question.getRecordClass().name() ) );
  
          Set<ResourceRecord> record = new HashSet<>();
  
          NamingEnumeration<SearchResult> answer = ctx.search( base, matchAttrs );
  
          if ( answer.hasMore() )
          {
              SearchResult result = answer.next();
  
              Attributes attrs = result.getAttributes();
  
              if ( attrs == null )
              {
                  return null;
              }
  
              record.add( getRecord( attrs ) );
         }
 
         return record;
     }
 
 
     /**
      * Marshals a RecordStoreEntry from an Attributes object.
      *
      * @param attrs the attributes of the DNS question
      * @return the entry for the question
      * @throws NamingException if there are any access problems
      */
     private ResourceRecord getRecord( Attributes attrs ) throws NamingException
     {
         ResourceRecordModifierssages/ResourceRecordModifier.html#ResourceRecordModifier">ResourceRecordModifier modifier = new ResourceRecordModifier();
 
         String dnsName = getAttrOrNull( attrs, DnsAttribute.NAME );
         String dnsType = getAttrOrNull( attrs, DnsAttribute.TYPE );
         String dnsClass = getAttrOrNull( attrs, DnsAttribute.CLASS );
         String dnsTtl = getAttrOrNull( attrs, DnsAttribute.TTL );
 
         modifier.setDnsName( dnsName );
         modifier.setDnsType( RecordType.valueOf( dnsType ) );
         modifier.setDnsClass( RecordClass.valueOf( dnsClass ) );
         modifier.setDnsTtl( Integer.parseInt( dnsTtl ) );
 
         NamingEnumeration<String> ids = attrs.getIDs();
 
         while ( ids.hasMore() )
         {
             String id = ids.next();
             modifier.put( id, ( String ) attrs.get( id ).get() );
         }
 
         return modifier.getEntry();
     }
 
 
     private String getAttrOrNull( Attributes attrs, String name ) throws NamingException
     {
         Attribute attr = attrs.get( name );
         return attr != null ? ( String ) attr.get() : null;
     }
 }