/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.maven.scm.provider.git.gitexe.command.info;
  
  import java.nio.file.Path;
  import java.time.format.DateTimeFormatter;
  
  import org.apache.commons.lang3.StringUtils;
  import org.apache.maven.scm.command.info.InfoItem;
  import org.apache.maven.scm.util.AbstractConsumer;
  import org.codehaus.plexus.util.cli.Arg;
  import org.codehaus.plexus.util.cli.Commandline;
  
  /**
   * Parses output of {@code git log} with a particular format and populates a {@link InfoItem}.
   *
   * @author Olivier Lamy
   * @since 1.5
   * @see <a href="https://git-scm.com/docs/git-log#_pretty_formats">Pretty Formats</a>
   */
  public class GitInfoConsumer extends AbstractConsumer {
  
      private final InfoItem infoItem;
      private final int revisionLength;
  
      public GitInfoConsumer(Path path, int revisionLength) {
          infoItem = new InfoItem();
          infoItem.setPath(path.toString());
          infoItem.setURL(path.toUri().toASCIIString());
          this.revisionLength = revisionLength;
      }
  
      enum LineParts {
          HASH(0),
          AUTHOR_NAME(3),
          AUTHOR_EMAIL(2),
          AUTHOR_LAST_MODIFIED(1);
  
          private final int index;
  
          LineParts(int index) {
              this.index = index;
          }
  
          public int getIndex() {
              return index;
          }
      }
  
      /**
       * @param line the line which is supposed to have the format as specified by {@link #getFormatArgument()}.
       * @see org.codehaus.plexus.util.cli.StreamConsumer#consumeLine(java.lang.String)
       */
      public void consumeLine(String line) {
          if (logger.isDebugEnabled()) {
              logger.debug("consume line {}", line);
          }
  
          // name must be last token as it may contain separators
          String[] parts = line.split("\\s", 4);
          if (parts.length != 4) {
              throw new IllegalArgumentException(
                      "Unexpected line: expecting 4 tokens separated by whitespace but got " + line);
          }
          infoItem.setLastChangedAuthor(
                  parts[LineParts.AUTHOR_NAME.getIndex()] + " <" + parts[LineParts.AUTHOR_EMAIL.getIndex()] + ">");
          String revision = parts[LineParts.HASH.getIndex()];
          if (revisionLength > -1) {
              // do not truncate below 4 characters
              revision = StringUtils.truncate(revision, Integer.max(4, revisionLength));
          }
          infoItem.setRevision(revision);
          infoItem.setLastChangedDateTime(
                  DateTimeFormatter.ISO_OFFSET_DATE_TIME.parse(parts[LineParts.AUTHOR_LAST_MODIFIED.getIndex()]));
      }
  
      public InfoItem getInfoItem() {
          return infoItem;
      }
  
      /**
       * The format argument to use with {@code git log}
       * @return the format argument to use {@code git log} command
      * @see <a href="https://git-scm.com/docs/git-log#_pretty_formats">Pretty Formats</a>
      */
     public static Arg getFormatArgument() {
         Commandline.Argument arg = new Commandline.Argument();
         arg.setValue("--format=format:%H %aI %aE %aN");
         return arg;
     }
 }