/*

     StatCvs - CVS statistics generation 

     Copyright (C) 2002  Lukasz Pekacki <lukasz@pekacki.de>

     http://statcvs.sf.net/

     This library is free software; you can redistribute it and/or

     modify it under the terms of the GNU Lesser General Public

     License as published by the Free Software Foundation; either

     version 2.1 of the License, or (at your option) any later version.

     This library 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

     Lesser General Public License for more details.

     You should have received a copy of the GNU Lesser General Public

     License along with this library; if not, write to the Free Software

     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

         $RCSfile: CvsRevisionParser.java,v $ 

         Created on $Date: 2008/04/02 11:22:15 $ 

 */

 package net.sf.statcvs.input;

 import java.io.IOException;

 import java.text.ParseException;

 import java.text.SimpleDateFormat;

 import java.util.Date;

 import java.util.Locale;

 import java.util.StringTokenizer;

 import java.util.logging.Logger;

 import net.sf.statcvs.util.LookaheadReader;

 /**

  * Parses all revisions of one file.

  * 

  * @author Anja Jentzsch

  * @author Richard Cyganiak

  * @version $Id: CvsRevisionParser.java,v 1.41 2008/04/02 11:22:15 benoitx Exp $

  */

 public class CvsRevisionParser {

     private static Logger logger = Logger.getLogger(CvsRevisionParser.class.getName());

     /**

      * Revision Delimiter in CVS log file

      */

     public static final String REVISION_DELIMITER = "----------------------------";

     /**

      * File Delimiter in CVS log file

      */

     public static final String FILE_DELIMITER = "======================================" + "=======================================";

     private static final String OLD_LOG_TIMESTAMP_FORMAT = "yyyy/MM/dd HH:mm:ss zzz";

     private static final String NEW_LOG_TIMESTAMP_FORMAT = "yyyy-MM-dd HH:mm:ss Z";

     private static final Locale LOG_TIMESTAMP_LOCALE = Locale.US;

     private static SimpleDateFormat oldLogTimeFormat = new SimpleDateFormat(OLD_LOG_TIMESTAMP_FORMAT, LOG_TIMESTAMP_LOCALE);

     private static SimpleDateFormat newLogTimeFormat = new SimpleDateFormat(NEW_LOG_TIMESTAMP_FORMAT, LOG_TIMESTAMP_LOCALE);

     private final LookaheadReader logReader;

     private final CvsLogBuilder builder;

     private boolean fileDone = false;

     private RevisionData revision;

     /**

      * Default Constructor CvsRevisionParser.

      * @param logReader the reader

      * @param builder a <tt>Builder</tt> for the creation process

      */

     public CvsRevisionParser(final LookaheadReader logReader, final CvsLogBuilder builder) {

         this.logReader = logReader;

         this.builder = builder;

     }

     /**

      * Parses the list of revisions for one file

      * @throws LogSyntaxException on syntax error in the log

      * @throws IOException on read error

      */

     public void parse() throws LogSyntaxException, IOException {

         this.logReader.nextLine();

         do {

             revision = new RevisionData();

             parseRevision();

             builder.buildRevision(revision);

         } while (!fileDone);

     }

     private void parseRevision() throws IOException, LogSyntaxException {

         if (!isNewRevisionLine(logReader.getCurrentLine())) {

             throw new LogSyntaxException("expected 'revision' but found '" + logReader.getCurrentLine() + "' in line " + logReader.getLineNumber());

         }

         final String revNo = logReader.getCurrentLine().substring("revision ".length());

         revision.setRevisionNumber(revNo);

         parseDateLine(this.logReader.nextLine());

         if (this.logReader.nextLine().startsWith("branches:")) {

             this.logReader.nextLine();

         }

         final StringBuffer comment = new StringBuffer();

         while (true) {

             final String line = logReader.getCurrentLine();

             if (REVISION_DELIMITER.equals(line)) {

                 final String next = this.logReader.nextLine();

                 if (isNewRevisionLine(next)) {

                     revision.setComment(comment.toString());

                     return;

                 }

             } else if (FILE_DELIMITER.equals(line)) {

                 if (!this.logReader.hasNextLine() || "".equals(this.logReader.nextLine())) {

                     this.revision.setComment(comment.toString());

                     this.fileDone = true;

                     return;

                 }

             } else {

                 this.logReader.nextLine();

             }

             if (comment.length() != 0) {

                 comment.append('\n');

             }

             comment.append(line);

         }

     }

     private void parseDateLine(final String line) throws LogSyntaxException {

         // date: 2000/06/19 04:56:21;  author: somebody;  state: Exp;  lines: +114 -45

         // get the creation date

         final int endOfDateIndex = line.indexOf(';', 6);

         final String dateString = line.substring(6, endOfDateIndex) + " GMT";

         final Date date = convertFromLogTime(dateString);

         if (date == null) {

             throw new LogSyntaxException("unexpected date format in line " + logReader.getLineNumber());

         }

         revision.setDate(date);

         // get the author name

         final int endOfAuthorIndex = line.indexOf(';', endOfDateIndex + 1);

         revision.setLoginName(line.substring(endOfDateIndex + 11, endOfAuthorIndex));

         // get the file state (because this revision might be "dead")

         final String fileState = line.substring(endOfAuthorIndex + 10, line.indexOf(';', endOfAuthorIndex + 1));

         if (isDeadState(fileState)) {

             revision.setStateDead();

             return;

         }

         revision.setStateExp();

         // is this an initial revision?

         final int beginOfLinesIndex = line.indexOf("lines:", endOfAuthorIndex + 1);

         if (beginOfLinesIndex < 0) {

             return;

         }

         // get lines added and lines removed

         final StringTokenizer st = new StringTokenizer(line.substring(beginOfLinesIndex + 8));

         final int linesAdded = Integer.parseInt(st.nextToken());

         String removed = st.nextToken();

         if (removed.indexOf(';') >= 0) {

             removed = removed.substring(0, removed.indexOf(';'));

         }

         final int linesRemoved = -Integer.parseInt(removed);

         revision.setLines(linesAdded, linesRemoved);

     }

     private boolean isNewRevisionLine(final String line) {

         return line.startsWith("revision ");

     }

     private boolean isDeadState(final String state) {

         if ("dead".equals(state)) {

             return true;

         }

         if ("Exp".equals(state) || "Stab".equals(state) || "Rel".equals(state)) {

             return false;

         }

         logger.warning("unknown file state '" + state + "' at line " + this.logReader.getLineNumber());

         return false;

     }

     /**

      * Returns a date from a given modTime String of a cvs logfile

      * @param modTime modTime String of a cvs logfile

      * @return Date date from a given modTime String of a cvs logfile

      */

     private static Date convertFromLogTime(final String modTime) {

         try {

             return oldLogTimeFormat.parse(modTime);

         } catch (final ParseException e) {

             // try other format

         }

         try {

             return newLogTimeFormat.parse(modTime);

         } catch (final ParseException e) {

             return null;

         }

     }

 }