/*
 * The contents of this file are subject to the terms of the Common Development and
 * Distribution License (the License). You may not use this file except in compliance with the
 * License.
 *
 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
 * specific language governing permission and limitations under the License.
 *
 * When distributing Covered Software, include this CDDL Header Notice in each file and include
 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
 * Header, with the fields enclosed by brackets [] replaced by your own identifying
 * information: "Portions Copyright [year] [name of copyright owner]".
 *
 * Copyright 2009 Sun Microsystems, Inc.
 * Portions Copyright 2014-2016 ForgeRock AS.
 */
package org.opends.server.controls;

import static org.opends.messages.ProtocolMessages.ERR_ECLN_CANNOT_DECODE_VALUE;
import static org.opends.messages.ProtocolMessages.ERR_ECLN_NO_CONTROL_VALUE;
import static org.opends.server.util.ServerConstants.*;
import static org.opends.server.util.StaticUtils.getExceptionMessage;

import java.io.IOException;

import org.forgerock.i18n.LocalizableMessage;
import org.forgerock.i18n.slf4j.LocalizedLogger;
import org.forgerock.opendj.io.ASN1;
import org.forgerock.opendj.io.ASN1Reader;
import org.forgerock.opendj.io.ASN1Writer;
import org.forgerock.opendj.ldap.ByteString;
import org.opends.server.types.Control;
import org.opends.server.types.DirectoryException;
import org.forgerock.opendj.ldap.ResultCode;

/**
 * This class implements the ECL cookie control.
 * It may be included in entries returned in response to a search or
 * persistent search operation.
 */
public class EntryChangelogNotificationControl
       extends Control
       {
  private static final LocalizedLogger logger = LocalizedLogger.getLoggerForThisClass();

  /** The cookie value - payload of this control. */
  private String cookie;

  /** ControlDecoder implementation to decode this control from a ByteString. */
  private static final class Decoder
  implements ControlDecoder<EntryChangelogNotificationControl>
  {
    @Override
    public EntryChangelogNotificationControl decode(
        boolean isCritical, ByteString value)
    throws DirectoryException
    {
      if (value == null)
      {
        LocalizableMessage message = ERR_ECLN_NO_CONTROL_VALUE.get();
        throw new DirectoryException(ResultCode.PROTOCOL_ERROR, message);
      }


      String cookie = null;
      ASN1Reader reader = ASN1.getReader(value);
      try
      {
        reader.readStartSequence();
        cookie = reader.readOctetStringAsString();
      }
      catch (Exception e)
      {
        logger.traceException(e);

        LocalizableMessage message =
          ERR_ECLN_CANNOT_DECODE_VALUE.get(getExceptionMessage(e));
        throw new DirectoryException(ResultCode.PROTOCOL_ERROR, message, e);
      }
      return new EntryChangelogNotificationControl(isCritical, cookie);
    }

    @Override
    public String getOID()
    {
      return OID_ECL_COOKIE_EXCHANGE_CONTROL;
    }

  }

  /** The Control Decoder that can be used to decode this control. */
  public static final ControlDecoder<EntryChangelogNotificationControl>
  DECODER = new Decoder();

  /**
   * Creates a new entry change notification control with the provided
   * information.
   *
   * @param  isCritical  Indicates whether this control should be
   *                     considered critical in processing the
   *                     request.
   * @param  cookie      The provided cookie value.
   */
  public EntryChangelogNotificationControl(boolean isCritical,
      String cookie)
  {
    super(OID_ECL_COOKIE_EXCHANGE_CONTROL, isCritical);
    this.cookie = cookie;
  }

  @Override
  public void writeValue(ASN1Writer writer) throws IOException {
    writer.writeStartSequence(ASN1.UNIVERSAL_OCTET_STRING_TYPE);
    writer.writeStartSequence();
    writer.writeOctetString(cookie);
    writer.writeEndSequence();
    writer.writeEndSequence();
  }



  /**
   * Retrieves the change type for this entry change notification control.
   *
   * @return  The change type for this entry change notification control.
   */
  public String getCookie()
  {
    return cookie;
  }

  @Override
  public void toString(StringBuilder buffer)
  {
    buffer.append("EntryChangelogNotificationControl(cookie=");
    buffer.append(cookie);
    buffer.append(")");
  }
}