/*
    *   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.shared.kerberos.components;
  
  
  import java.nio.BufferOverflowException;
  import java.nio.ByteBuffer;
  
  import org.apache.directory.api.asn1.Asn1Object;
  import org.apache.directory.api.asn1.EncoderException;
  import org.apache.directory.api.asn1.ber.tlv.BerValue;
  import org.apache.directory.api.asn1.ber.tlv.TLV;
  import org.apache.directory.api.asn1.ber.tlv.UniversalTag;
  import org.apache.directory.api.util.Strings;
  import org.apache.directory.server.i18n.I18n;
  import org.apache.directory.shared.kerberos.KerberosConstants;
  import org.apache.directory.shared.kerberos.KerberosTime;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * Class representing KRB-SAFE-BODY message
   * 
   * <pre>
   * KRB-SAFE-BODY   ::= SEQUENCE {
   *         user-data       [0] OCTET STRING,
   *         timestamp       [1] KerberosTime OPTIONAL,
   *         usec            [2] Microseconds OPTIONAL,
   *         seq-number      [3] UInt32 OPTIONAL,
   *         s-address       [4] HostAddress,
   *         r-address       [5] HostAddress OPTIONAL
   * }
   *</pre>
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class KrbSafeBody implements Asn1Object
  {
      /** The logger */
      private static final Logger log = LoggerFactory.getLogger( KrbSafeBody.class );
  
      /** Speedup for logs */
      private static final boolean IS_DEBUG = log.isDebugEnabled();
  
      /** the user data */
      private byte[] userData;
  
      /** the current time of the sender */
      private KerberosTime timestamp;
  
      /** the microsecond part of the timestamp */
      private Integer usec;
  
      /** the sequence number */
      private Integer seqNumber;
  
      /** the sender's address */
      private HostAddress senderAddress;
  
      /** the recipient's address */
      private HostAddress recipientAddress;
  
      // Storage for computed lengths
      private int userDataLen;
      private int timestampLen;
      private int usecLen;
      private int seqNumberLen;
      private int senderAddressLen;
      private int recipientAddressLen;
      private int krbSafeBodySeqLen;
  
  
      /**
       * Creates a new instance of KrbSafeBody.
       */
      public KrbSafeBody()
      {
      }
  
  
      /**
      * @return the userData
      */
     public byte[] getUserData()
     {
         return userData;
     }
 
 
     /**
      * @param userData the userData to set
      */
     public void setUserData( byte[] userData )
     {
         this.userData = userData;
     }
 
 
     /**
      * @return the timestamp
      */
     public KerberosTime getTimestamp()
     {
         return timestamp;
     }
 
 
     /**
      * @param timestamp the timestamp to set
      */
     public void setTimestamp( KerberosTime timestamp )
     {
         this.timestamp = timestamp;
     }
 
 
     /**
      * @return the usec
      */
     public int getUsec()
     {
         if ( usec == null )
         {
             return 0;
         }
 
         return usec;
     }
 
 
     /**
      * @param usec the usec to set
      */
     public void setUsec( int usec )
     {
         this.usec = usec;
     }
 
 
     /**
      * @return the seqNumber
      */
     public int getSeqNumber()
     {
         if ( seqNumber == null )
         {
             return 0;
         }
 
         return seqNumber;
     }
 
 
     /**
      * @param seqNumber the seqNumber to set
      */
     public void setSeqNumber( int seqNumber )
     {
         this.seqNumber = seqNumber;
     }
 
 
     /**
      * @return the senderAddress
      */
     public HostAddress getSenderAddress()
     {
         return senderAddress;
     }
 
 
     /**
      * @param senderAddress the senderAddress to set
      */
     public void setSenderAddress( HostAddress senderAddress )
     {
         this.senderAddress = senderAddress;
     }
 
 
     /**
      * @return the recipientAddress
      */
     public HostAddress getRecipientAddress()
     {
         return recipientAddress;
     }
 
 
     /**
      * @param recipientAddress the recipientAddress to set
      */
     public void setRecipientAddress( HostAddress recipientAddress )
     {
         this.recipientAddress = recipientAddress;
     }
 
 
     /**
      * Compute the KRB-SAFE-BODY length:
      * 
      * <pre>
      * 0x30 L1 KRB-SAFE-BODY SEQ
      *  |
      *  +--&gt; 0xA0 L2 user-data tag
      *  |     |
      *  |     +--&gt; 0x04 L2-1 user-data (Octet String)
      *  |
      *  +--&gt; 0xA1 0x11 timestamp tag
      *  |     |
      *  |     +--&gt; 0x18 0x0F timestamp (KerberosTime)
      *  |
      *  +--&gt; 0xA2 L3 usec tag
      *  |     |
      *  |     +--&gt; 0x02 L3-1 usec (Microseconds)
      *  |
      *  +--&gt; 0xA3 L4 seq-number tag
      *  |     |
      *  |     +--&gt; 0x02 L4-1 seqnumber (UInt32)
      *  |
      *  +--&gt; 0xA4 L5 s-address tag
      *  |     |
      *  |     +--&gt; 0x30 L5-1 s-address (HostAddress)
      *  |
      *  +--&gt; 0xA5 L6 r-address tag
      *        |
      *        +--&gt; 0x30 L6-1 r-address (HostAddress)
      * </pre>       
      */
     @Override
     public int computeLength()
     {
         userDataLen = 1 + TLV.getNbBytes( userData.length ) + userData.length;
         krbSafeBodySeqLen = 1 + TLV.getNbBytes( userDataLen ) + userDataLen;
 
         senderAddressLen = senderAddress.computeLength();
         krbSafeBodySeqLen += 1 + TLV.getNbBytes( senderAddressLen ) + senderAddressLen;
 
         if ( timestamp != null )
         {
             timestampLen = timestamp.getBytes().length;
             timestampLen = 1 + TLV.getNbBytes( timestampLen ) + timestampLen;
             krbSafeBodySeqLen += 1 + TLV.getNbBytes( timestampLen ) + timestampLen;
         }
 
         if ( usec != null )
         {
             usecLen = BerValue.getNbBytes( usec );
             usecLen = 1 + TLV.getNbBytes( usecLen ) + usecLen;
             krbSafeBodySeqLen += 1 + TLV.getNbBytes( usecLen ) + usecLen;
         }
 
         if ( seqNumber != null )
         {
             seqNumberLen = BerValue.getNbBytes( seqNumber );
             seqNumberLen = 1 + TLV.getNbBytes( seqNumberLen ) + seqNumberLen;
             krbSafeBodySeqLen += 1 + TLV.getNbBytes( seqNumberLen ) + seqNumberLen;
         }
 
         if ( recipientAddress != null )
         {
             recipientAddressLen = recipientAddress.computeLength();
             krbSafeBodySeqLen += 1 + TLV.getNbBytes( recipientAddressLen ) + recipientAddressLen;
         }
 
         return 1 + TLV.getNbBytes( krbSafeBodySeqLen ) + krbSafeBodySeqLen;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public ByteBuffer encode( ByteBuffer buffer ) throws EncoderException
     {
         if ( buffer == null )
         {
             throw new EncoderException( I18n.err( I18n.ERR_148 ) );
         }
 
         try
         {
             buffer.put( UniversalTag.SEQUENCE.getValue() );
             buffer.put( TLV.getBytes( krbSafeBodySeqLen ) );
 
             // user-data
             buffer.put( ( byte ) KerberosConstants.KRB_SAFE_BODY_USER_DATA_TAG );
             buffer.put( TLV.getBytes( userDataLen ) );
             BerValue.encode( buffer, userData );
 
             if ( timestamp != null )
             {
                 // timestamp tag
                 buffer.put( ( byte ) KerberosConstants.KRB_SAFE_BODY_TIMESTAMP_TAG );
                 buffer.put( TLV.getBytes( timestampLen ) );
 
                 // timestamp value
                 buffer.put( UniversalTag.GENERALIZED_TIME.getValue() );
                 buffer.put( ( byte ) 0x0F );
                 buffer.put( timestamp.getBytes() );
             }
 
             if ( usec != null )
             {
                 // usec
                 buffer.put( ( byte ) KerberosConstants.KRB_SAFE_BODY_USEC_TAG );
                 buffer.put( TLV.getBytes( usecLen ) );
                 BerValue.encode( buffer, usec );
             }
 
             if ( seqNumber != null )
             {
                 // seq-number
                 buffer.put( ( byte ) KerberosConstants.KRB_SAFE_BODY_SEQ_NUMBER_TAG );
                 buffer.put( TLV.getBytes( seqNumberLen ) );
                 BerValue.encode( buffer, seqNumber );
             }
 
             // s-address
             buffer.put( ( byte ) KerberosConstants.KRB_SAFE_BODY_SENDER_ADDRESS_TAG );
             buffer.put( TLV.getBytes( senderAddressLen ) );
             senderAddress.encode( buffer );
 
             if ( recipientAddress != null )
             {
                 // s-address
                 buffer.put( ( byte ) KerberosConstants.KRB_SAFE_BODY_RECIPIENT_ADDRESS_TAG );
                 buffer.put( TLV.getBytes( recipientAddressLen ) );
                 recipientAddress.encode( buffer );
             }
         }
         catch ( BufferOverflowException boe )
         {
             log.error( I18n.err( I18n.ERR_735_CANNOT_ENCODE_KRBSAFEBODY, 1 + TLV.getNbBytes( krbSafeBodySeqLen )
                 + krbSafeBodySeqLen, buffer.capacity() ) );
             throw new EncoderException( I18n.err( I18n.ERR_138 ), boe );
         }
 
         if ( IS_DEBUG )
         {
             log.debug( "KrbSafeBody encoding : {}", Strings.dumpBytes( buffer.array() ) );
             log.debug( "KrbSafeBody initial value : {}", this );
         }
 
         return buffer;
     }
 
 
     /**
      * @see Object#toString()
      */
     public String toString()
     {
         StringBuilder sb = new StringBuilder();
 
         sb.append( "KRB-SAFE-BODY : {\n" );
         sb.append( "    user-data: " ).append( Strings.dumpBytes( userData ) ).append( '\n' );
 
         if ( timestamp != null )
         {
             sb.append( "    timestamp: " ).append( timestamp.getDate() ).append( '\n' );
         }
 
         if ( usec != null )
         {
             sb.append( "    usec: " ).append( usec ).append( '\n' );
         }
 
         if ( seqNumber != null )
         {
             sb.append( "    seq-number: " ).append( seqNumber ).append( '\n' );
         }
 
         sb.append( "    s-address: " ).append( senderAddress ).append( '\n' );
 
         if ( recipientAddress != null )
         {
             sb.append( "    r-address: " ).append( recipientAddress ).append( '\n' );
         }
 
         sb.append( "}\n" );
 
         return sb.toString();
     }
 }