/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at
 * trunk/opends/resource/legal-notices/OpenDS.LICENSE
 * or https://OpenDS.dev.java.net/OpenDS.LICENSE.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at
 * trunk/opends/resource/legal-notices/OpenDS.LICENSE.  If applicable,
 * add the following below this CDDL HEADER, with the fields enclosed
 * by brackets "[]" replaced with your own identifying * information:
 *      Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 *
 *      Portions Copyright 2006 Sun Microsystems, Inc.
 */
package org.opends.server.synchronization.protocol;

import java.io.Serializable;
import java.io.UnsupportedEncodingException;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.zip.DataFormatException;

import org.opends.server.synchronization.common.ServerState;
import org.opends.server.types.DirectoryException;
import org.opends.server.types.DN;

/**
 * This message is used by LDAP server when they first connect.
 * to a changelog server to let them know who they are and what is their state
 * (their RUV)
 */
public class ServerStartMessage extends SynchronizationMessage implements
    Serializable
{
  private static final long serialVersionUID = 8649393307038290287L;

  private short serverId; // Id of the LDAP server that sent this message
  private String serverURL;
  private String baseDn;
  private int maxReceiveQueue;
  private int maxSendQueue;
  private int maxReceiveDelay;
  private int maxSendDelay;
  private int windowSize;
  private ServerState serverState = null;

  /**
   * The time in milliseconds between heartbeats from the synchronization
   * server.  Zero means heartbeats are off.
   */
  private long heartbeatInterval = 0;

  /**
   * Create a new ServerStartMessage.
   *
   * @param serverId The serverId of the server for which the ServerStartMessage
   *                 is created.
   * @param baseDn   The base DN.
   * @param maxReceiveDelay The max receive delay for this server.
   * @param maxReceiveQueue The max receive Queue for this server.
   * @param maxSendDelay The max Send Delay from this server.
   * @param maxSendQueue The max send Queue from this server.
   * @param windowSize   The window size used by this server.
   * @param heartbeatInterval The requested heartbeat interval.
   * @param serverState  The state of this server.
   */
  public ServerStartMessage(short serverId, DN baseDn, int maxReceiveDelay,
                            int maxReceiveQueue, int maxSendDelay,
                            int maxSendQueue, int windowSize,
                            long heartbeatInterval,
                            ServerState serverState)
  {
    this.serverId = serverId;
    this.baseDn = baseDn.toString();
    this.maxReceiveDelay = maxReceiveDelay;
    this.maxReceiveQueue = maxReceiveQueue;
    this.maxSendDelay = maxSendDelay;
    this.maxSendQueue = maxSendQueue;
    this.windowSize = windowSize;
    this.heartbeatInterval = heartbeatInterval;

    this.serverState = serverState;

    try
    {
      /* TODO : find a better way to get the server URL */
      this.serverURL = InetAddress.getLocalHost().getHostName();
    } catch (UnknownHostException e)
    {
      this.serverURL = "Unknown host";
    }
  }

  /**
   * Creates a new ServerStartMessage from its encoded form.
   *
   * @param in The byte array containing the encoded form of the
   *           ServerStartMessage.
   * @throws DataFormatException If the byte array does not contain a valid
   *                             encoded form of the ServerStartMessage.
   */
  public ServerStartMessage(byte[] in) throws DataFormatException
  {
    /* The ServerStartMessage is encoded in the form :
     * <operation type><baseDn><ServerId><ServerUrl><maxRecvDelay><maxRecvQueue>
     * <maxSendDelay><maxSendQueue><window><heartbeatInterval><ServerState>
     */
    try
    {
      /* first byte is the type */
      if (in[0] != MSG_TYPE_SERVER_START)
        throw new DataFormatException("input is not a valid ServerStart msg");
      int pos = 1;

      /*
       * read the dn
       * first calculate the length then construct the string
       */
      int length = getNextLength(in, pos);
      baseDn = new String(in, pos, length, "UTF-8");
      pos += length +1;

      /*
       * read the ServerId
       */
      length = getNextLength(in, pos);
      String serverIdString = new String(in, pos, length, "UTF-8");
      serverId = Short.valueOf(serverIdString);
      pos += length +1;

      /*
       * read the ServerURL
       */
      length = getNextLength(in, pos);
      serverURL = new String(in, pos, length, "UTF-8");
      pos += length +1;

      /*
       * read the maxReceiveDelay
       */
      length = getNextLength(in, pos);
      maxReceiveDelay = Integer.valueOf(new String(in, pos, length, "UTF-8"));
      pos += length +1;

      /*
       * read the maxReceiveQueue
       */
      length = getNextLength(in, pos);
      maxReceiveQueue = Integer.valueOf(new String(in, pos, length, "UTF-8"));
      pos += length +1;

      /*
       * read the maxSendDelay
       */
      length = getNextLength(in, pos);
      maxSendDelay = Integer.valueOf(new String(in, pos, length, "UTF-8"));
      pos += length +1;

      /*
       * read the maxSendQueue
       */
      length = getNextLength(in, pos);
      maxSendQueue = Integer.valueOf(new String(in, pos, length, "UTF-8"));
      pos += length +1;

      /*
       * read the windowSize
       */
      length = getNextLength(in, pos);
      windowSize = Integer.valueOf(new String(in, pos, length, "UTF-8"));
      pos += length +1;

      /*
       * read the heartbeatInterval
       */
      length = getNextLength(in, pos);
      heartbeatInterval = Integer.valueOf(new String(in, pos, length, "UTF-8"));
      pos += length +1;

      /*
      * read the ServerState
      */
      serverState = new ServerState(in, pos, in.length-1);
    } catch (UnsupportedEncodingException e)
    {
      throw new DataFormatException("UTF-8 is not supported by this jvm.");
    }
  }

  /**
   * Get the ServerID from the message.
   * @return the server ID
   */
  public short getServerId()
  {
    return serverId;
  }

  /**
   * get the Server URL from the message.
   * @return the server URL
   */
  public String getServerURL()
  {
    return serverURL;
  }

  /**
   * Get the baseDn.
   * @return Returns the baseDn.
   */
  public DN getBaseDn()
  {
    try
    {
      return DN.decode(baseDn);
    } catch (DirectoryException e)
    {
      return null;
    }
  }

  /**
   * Get the maxReceiveDelay.
   * @return Returns the maxReceiveDelay.
   */
  public int getMaxReceiveDelay()
  {
    return maxReceiveDelay;
  }

  /**
   * Get the maxReceiveQueue.
   * @return Returns the maxReceiveQueue.
   */
  public int getMaxReceiveQueue()
  {
    return maxReceiveQueue;
  }

  /**
   * Get the maxSendDelay.
   * @return Returns the maxSendDelay.
   */
  public int getMaxSendDelay()
  {
    return maxSendDelay;
  }

  /**
   * Get the maxSendQueue.
   * @return Returns the maxSendQueue.
   */
  public int getMaxSendQueue()
  {
    return maxSendQueue;
  }

  /**
   * Get the ServerState.
   * @return The ServerState.
   */
  public ServerState getServerState()
  {
    return serverState;
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public byte[] getBytes()
  {
    /*
     * ServerStartMessage contains.
     * <baseDn><ServerId><ServerUrl><maxRecvDelay><maxRecvQueue>
     * <maxSendDelay><maxSendQueue><windowsize><heartbeatInterval><ServerState>
     */
    try {
      byte[] byteDn = baseDn.getBytes("UTF-8");
      byte[] byteServerId = String.valueOf(serverId).getBytes("UTF-8");
      byte[] byteServerUrl = serverURL.getBytes("UTF-8");
      byte[] byteMaxRecvDelay =
                     String.valueOf(maxReceiveDelay).getBytes("UTF-8");
      byte[] byteMaxRecvQueue =
                     String.valueOf(maxReceiveQueue).getBytes("UTF-8");
      byte[] byteMaxSendDelay =
                     String.valueOf(maxSendDelay).getBytes("UTF-8");
      byte[] byteMaxSendQueue =
                     String.valueOf(maxSendQueue).getBytes("UTF-8");
      byte[] byteWindowSize =
                     String.valueOf(windowSize).getBytes("UTF-8");
      byte[] byteHeartbeatInterval =
                     String.valueOf(heartbeatInterval).getBytes("UTF-8");
      byte[] byteServerState = serverState.getBytes();

      int length = 1 + byteDn.length + 1 + byteServerId.length + 1 +
                   byteServerUrl.length + 1 +
                   byteMaxRecvDelay.length + 1 +
                   byteMaxRecvQueue.length + 1 +
                   byteMaxSendDelay.length + 1 +
                   byteMaxSendQueue.length + 1 +
                   byteWindowSize.length + 1 +
                   byteHeartbeatInterval.length + 1 +
                   byteServerState.length + 1;

      byte[] resultByteArray = new byte[length];

      /* put the type of the operation */
      resultByteArray[0] = MSG_TYPE_SERVER_START;
      int pos = 1;

      pos = addByteArray(byteDn, resultByteArray, pos);

      pos = addByteArray(byteServerId, resultByteArray, pos);

      pos = addByteArray(byteServerUrl, resultByteArray, pos);

      pos = addByteArray(byteMaxRecvDelay, resultByteArray, pos);

      pos = addByteArray(byteMaxRecvQueue, resultByteArray, pos);

      pos = addByteArray(byteMaxSendDelay, resultByteArray, pos);

      pos = addByteArray(byteMaxSendQueue, resultByteArray, pos);

      pos = addByteArray(byteWindowSize, resultByteArray, pos);

      pos = addByteArray(byteHeartbeatInterval, resultByteArray, pos);

      pos = addByteArray(byteServerState, resultByteArray, pos);

      return resultByteArray;
    }
    catch (UnsupportedEncodingException e)
    {
      return null;
    }
  }

  /**
   * Get the window size for the ldap server that created the message.
   *
   * @return The window size for the ldap server that created the message.
   */
  public int getWindowSize()
  {
    return windowSize;
  }

  /**
   * Get the heartbeat interval requested by the ldap server that created the
   * message.
   *
   * @return The heartbeat interval requested by the ldap server that created
   * the message.
   */
  public long getHeartbeatInterval()
  {
    return heartbeatInterval;
  }
}