/*
    * 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.rfc4217;
  
  import org.waarp.common.command.ReplyCode;
  import org.waarp.common.command.exception.CommandAbstractException;
  import org.waarp.common.command.exception.Reply501Exception;
  import org.waarp.common.command.exception.Reply503Exception;
  import org.waarp.common.command.exception.Reply504Exception;
  import org.waarp.common.command.exception.Reply534Exception;
  import org.waarp.common.logging.WaarpLogger;
  import org.waarp.common.logging.WaarpLoggerFactory;
  import org.waarp.ftp.core.command.AbstractCommand;
  
  /**
   * AUTH command with 2 options TLS or SSL<br>
   * <br>
   * Security Association Setup AUTH TLS (Control) or AUTH SSL (Control and
   * Data)<br>
   * 234*<br>
   * 502, 504, 534*, 431* 500, 501, 421<br>
   * <br>
   * AUTH TLS -> 234 -> USER or ([PBSZ 0] PROT P then USER) -> 2xy
   */
  public class AUTH extends AbstractCommand {
    /**
     * Internal Logger
     */
    private static final WaarpLogger logger =
        WaarpLoggerFactory.getLogger(AUTH.class);
  
    @Override
    public final void exec() throws CommandAbstractException {
      if (!getSession().getConfiguration().getFtpInternalConfiguration()
                       .isAcceptAuthProt()) {
        throw new Reply534Exception("AUTH SSL / TLS not supported");
      }
      if (getSession().isSsl()) {
        // Already SSL
        throw new Reply503Exception("Session already using SSL / TLS");
      }
      // First Check if any argument
      if (!hasArg()) {
        // Error since argument is needed
        throw new Reply501Exception("Missing Parameter: TLS or SSL");
      }
      final String[] types = getArgs();
      if ("TLS".equalsIgnoreCase(types[0])) {
        // Only Command will have SSL
        logger.debug("Start TLS");
        getSession().rein();
        getSession().setNextCommand(this);
        getSession().setReplyCode(
            ReplyCode.REPLY_234_SECURITY_DATA_EXCHANGE_COMPLETE, null);
      } else if ("SSL".equalsIgnoreCase(types[0])) {
        // Both Command and Data will have SSL
        logger.debug("Start SSL");
        getSession().rein();
        getSession().setNextCommand(this);
        getSession().setReplyCode(
            ReplyCode.REPLY_234_SECURITY_DATA_EXCHANGE_COMPLETE, null);
        getSession().setDataSsl(true);
      } else {
        throw new Reply504Exception("Unknown Parameter: " + types[0]);
      }
      logger.debug("End of AUTH {}", types[0]);
    }
  
  }