/*
    * This file is part of Waarp Project (named also Waarp or GG).
    *
    *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
    *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
    * individual contributors.
    *
    *  All Waarp Project is free software: you can redistribute it and/or
    * modify it under the terms of the GNU General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or (at your
   * option) any later version.
   *
   * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY
   * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along with
   * Waarp . If not, see <http://www.gnu.org/licenses/>.
   */
  package org.waarp.ftp.core.command.parameter;
  
  import org.waarp.common.command.ReplyCode;
  import org.waarp.common.command.exception.Reply501Exception;
  import org.waarp.common.logging.WaarpLogger;
  import org.waarp.common.logging.WaarpLoggerFactory;
  import org.waarp.ftp.core.command.AbstractCommand;
  import org.waarp.ftp.core.config.FtpConfiguration;
  import org.waarp.ftp.core.utils.FtpChannelUtils;
  
  import java.net.InetAddress;
  import java.net.InetSocketAddress;
  
  /**
   * PORT command
   */
  public class PORT extends AbstractCommand {
    /**
     * Internal Logger
     */
    private static final WaarpLogger logger =
        WaarpLoggerFactory.getLogger(PORT.class);
  
    @Override
    public final void exec() throws Reply501Exception {
      // Check if Active mode is OK
      if (((FtpConfiguration) (FtpConfiguration.ftpConfiguration)).getActivePassiveMode() <
          0) {
        // Passive only
        throw new Reply501Exception("Active mode not allowed");
      }
      // First Check if any argument
      if (!hasArg()) {
        final InetSocketAddress inetSocketAddress =
            getSession().getDataConn().getRemoteAddress();
        getSession().getDataConn().setActive(inetSocketAddress);
        getSession().setReplyCode(ReplyCode.REPLY_200_COMMAND_OKAY,
                                  "PORT command successful on (" +
                                  inetSocketAddress + ')');
        return;
      }
      // Check if Inet Address is OK
      final InetSocketAddress inetSocketAddress =
          FtpChannelUtils.getInetSocketAddress(getArg());
      if (inetSocketAddress == null) {
        // ERROR
        throw new Reply501Exception("Need correct Inet Address as argument");
      }
      // Check if the Client address is the same as given
      final InetAddress remoteAddress = inetSocketAddress.getAddress();
      final InetAddress trueRemoteAddress =
          getSession().getDataConn().getRemoteAddress().getAddress();
      if (!remoteAddress.equals(trueRemoteAddress)) {
        // ERROR
        logger.warn("Given Inet Address {} mismatchs actual client Address {}",
                    remoteAddress, trueRemoteAddress);
        throw new Reply501Exception(
            "Given Inet Address mismatchs actual client Address");
      }
      // OK now try to initialize connection (not open)
      getSession().getDataConn().setActive(inetSocketAddress);
      getSession().setReplyCode(ReplyCode.REPLY_200_COMMAND_OKAY,
                                "PORT command successful on (" +
                                inetSocketAddress + ')');
    }
  }