/*
    * 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.openr66.context.task.javatask;
  
  import org.waarp.common.database.exception.WaarpDatabaseException;
  import org.waarp.common.digest.FilesystemBasedDigest;
  import org.waarp.common.digest.FilesystemBasedDigest.DigestAlgo;
  import org.waarp.common.logging.WaarpLogger;
  import org.waarp.common.logging.WaarpLoggerFactory;
  import org.waarp.openr66.context.task.AbstractExecJavaTask;
  
  import java.io.IOException;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  /**
   * Add a digest in the TransferInformation to the current Task.</br>
   * This should be called on caller side in pre-task since the transfer
   * information will be transfered just
   * after.</br>
   * The second argument is -digest followed by one of ADLER32 CRC32 MD2 MD5 SHA1
   * SHA256 SHA384 SHA512, default
   * being MD5.</br>
   * The third argument, optional, is "-format" followed by a string containing
   * "#DIGEST#" to be replaced by the
   * digest and starting with - or +, meaning this will be added at the beginning
   * or the end of the generated
   * new string. Default is equivalent to "-format -##DIGEST##".</br>
   * </br>
   * To be called as: <task><type>EXECJAVA</type><path>org.waarp.openr66.context.task.javatask.AddDigestJavaTask
   * -digest ADLER32|CRC32|MD2|MD5|SHA1|SHA256|SHA384|SHA512 [-format
   * (-/+)##DIGEST##]</path></task>
   */
  public class AddDigestJavaTask extends AbstractExecJavaTask {
    /**
     * Internal Logger
     */
    private static final WaarpLogger logger =
        WaarpLoggerFactory.getLogger(AddDigestJavaTask.class);
  
    private static final String S_DIGEST = "#DIGEST#";
    private static final Pattern DIGEST_PATTERN =
        Pattern.compile(S_DIGEST, Pattern.LITERAL);
  
    @Override
    public final void run() {
      logger.debug("{}", this);
      final String[] args = BLANK.split(fullarg);
      final String fileInfo;
      String format = "-##DIGEST##";
      String algo = "MD5";
      int way = -1;
      for (int i = 0; i < args.length; i++) {
        if ("-format".equalsIgnoreCase(args[i])) {
          format = args[i + 1];
          if (format.charAt(0) == '-') {
            way = -1;
            format = format.substring(1);
          } else if (format.charAt(0) == '+') {
            way = 1;
            format = format.substring(1);
          }
          i++;
        } else if ("-digest".equals(args[i])) {
          algo = args[i + 1].toUpperCase();
          i++;
        }
      }
      final DigestAlgo digest;
      try {
        digest = DigestAlgo.valueOf(algo);
      } catch (final Exception e) {
        logger.error("Bad algorithm format: " + algo);
        status = 3;
        return;
      }
      final String key;
      try {
        key = FilesystemBasedDigest.getHex(
            FilesystemBasedDigest.getHash(session.getFile().getTrueFile(), true,
                                          digest));
      } catch (final IOException e1) {
       logger.error("Digest not correctly computed: " + algo + ": {}",
                    e1.getMessage());
       status = 4;
       return;
     }
     logger.debug("Replace Digest in {} way: {} digest: {} key: {}", format, way,
                  algo, key);
     if (format.isEmpty()) {
       fileInfo = session.getRunner().getFileInformation();
     } else {
       if (way < 0) {
         fileInfo = DIGEST_PATTERN.matcher(format)
                                  .replaceAll(Matcher.quoteReplacement(key)) +
                    ' ' + session.getRunner().getFileInformation();
       } else {
         fileInfo = session.getRunner().getFileInformation() + ' ' +
                    DIGEST_PATTERN.matcher(format)
                                  .replaceAll(Matcher.quoteReplacement(key));
       }
     }
     session.getRunner().setFileInformation(fileInfo);
     session.getRunner().addToTransferMap("digest", key);
     try {
       session.getRunner().update();
     } catch (final WaarpDatabaseException e) {
       logger.error("Digest cannot be saved to fileInformation:" + fileInfo);
       status = 2;
       return;
     }
     logger.debug("Digest saved to fileInformation: {}", fileInfo);
     status = 0;
   }
 }