/*
    * 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.svn.svnexe.command.blame;
  
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  import java.util.ArrayList;
  import java.util.Date;
  import java.util.List;
  import java.util.TimeZone;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import org.apache.maven.scm.command.blame.BlameLine;
  import org.apache.maven.scm.util.AbstractConsumer;
  
  /**
   * @author Evgeny Mandrikov
   * @author Olivier Lamy
   * @since 1.4
   */
  public class SvnBlameConsumer extends AbstractConsumer {
      private static final String SVN_TIMESTAMP_PATTERN = "yyyy-MM-dd HH:mm:ss";
  
      private static final Pattern LINE_PATTERN = Pattern.compile("line-number=\"(.*)\"");
  
      private static final Pattern REVISION_PATTERN = Pattern.compile("revision=\"(.*)\"");
  
      private static final Pattern AUTHOR_PATTERN = Pattern.compile("<author>(.*)</author>");
  
      private static final Pattern DATE_PATTERN = Pattern.compile("<date>(.*)T(.*)\\.(.*)Z</date>");
  
      private final SimpleDateFormat dateFormat;
  
      private final List<BlameLine> lines = new ArrayList<>();
  
      public SvnBlameConsumer() {
          dateFormat = new SimpleDateFormat(SVN_TIMESTAMP_PATTERN);
          dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
      }
  
      private int lineNumber;
  
      private String revision;
  
      private String author;
  
      public void consumeLine(String line) {
          Matcher matcher;
          if ((matcher = LINE_PATTERN.matcher(line)).find()) {
              String lineNumberStr = matcher.group(1);
              lineNumber = Integer.parseInt(lineNumberStr);
          } else if ((matcher = REVISION_PATTERN.matcher(line)).find()) {
              revision = matcher.group(1);
          } else if ((matcher = AUTHOR_PATTERN.matcher(line)).find()) {
              author = matcher.group(1);
          } else if ((matcher = DATE_PATTERN.matcher(line)).find()) {
              String date = matcher.group(1);
              String time = matcher.group(2);
              Date dateTime = parseDateTime(date + " " + time);
              lines.add(new BlameLine(dateTime, revision, author));
              if (logger.isDebugEnabled()) {
                  logger.debug("Author of line " + lineNumber + ": " + author + " (" + date + ")");
              }
          }
      }
  
      protected Date parseDateTime(String dateTimeStr) {
          try {
              return dateFormat.parse(dateTimeStr);
          } catch (ParseException e) {
              logger.error("skip ParseException: " + e.getMessage() + " during parsing date " + dateTimeStr, e);
              return null;
          }
      }
  
      public List<BlameLine> getLines() {
          return lines;
      }
  }