package org.apache.maven.scm.provider.perforce.command.changelog;

 /*

  * 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.

  */

 import java.util.ArrayList;

 import java.util.List;

 import org.apache.maven.scm.ChangeFile;

 import org.apache.maven.scm.ChangeSet;

 import org.apache.maven.scm.ScmException;

 import org.apache.maven.scm.log.ScmLogger;

 import org.apache.maven.scm.util.AbstractConsumer;

 import org.apache.regexp.RE;

 import org.apache.regexp.RESyntaxException;

 /**

  * Parse the tagged output from "p4 describe -s [change] [change] [...]".

  *

  * @author <a href="mailto:evenisse@apache.org">Emmanuel Venisse</a>

  * @author Olivier Lamy

  * @version $Id: PerforceDescribeConsumer.java 1054408 2011-01-02 14:05:25Z olamy $

  */

 public class PerforceDescribeConsumer

     extends AbstractConsumer

 {

     private List<ChangeSet> entries = new ArrayList<ChangeSet>();

     /**

      * State machine constant: expecting revision

      */

     private static final int GET_REVISION = 1;

     /**

      * State machine constant: eat the first blank line

      */

     private static final int GET_COMMENT_BEGIN = 2;

     /**

      * State machine constant: expecting comments

      */

     private static final int GET_COMMENT = 3;

     /**

      * State machine constant: expecting "Affected files"

      */

     private static final int GET_AFFECTED_FILES = 4;

     /**

      * State machine constant: expecting blank line

      */

     private static final int GET_FILES_BEGIN = 5;

     /**

      * State machine constant: expecting files

      */

     private static final int GET_FILE = 6;

     /**

      * Current status of the parser

      */

     private int status = GET_REVISION;

     /**

      * The current log entry being processed by the parser

      */

     @SuppressWarnings( "unused" )

     private String currentRevision;

     /**

      * The current log entry being processed by the parser

      */

     private ChangeSet currentChange;

     /**

      * the current file being processed by the parser

      */

     private String currentFile;

     /**

      * The location of files within the Perforce depot that we are processing

      * e.g. //depot/projects/foo/bar

      */

     private String repoPath;

     private String userDatePattern;

     private static final String REVISION_PATTERN = "^Change (\\d+) " + // changelist number

         "by (.*)@[^ ]+ " + // author

         "on (.*)"; // date

     /**

      * The comment section ends with a blank line

      */

     private static final String COMMENT_DELIMITER = "";

     /**

      * The changelist ends with a blank line

      */

     private static final String CHANGELIST_DELIMITER = "";

     private static final String FILE_PATTERN = "^\\.\\.\\. (.*)#(\\d+) ";

     /**

      * The regular expression used to match header lines

      */

     private RE revisionRegexp;

     /**

      * The regular expression used to match file paths

      */

     private RE fileRegexp;

     public PerforceDescribeConsumer( String repoPath, String userDatePattern, ScmLogger logger )

     {

         super( logger );

         this.repoPath = repoPath;

         this.userDatePattern = userDatePattern;

         try

         {

             revisionRegexp = new RE( REVISION_PATTERN );

             fileRegexp = new RE( FILE_PATTERN );

         }

         catch ( RESyntaxException ignored )

         {

             if ( getLogger().isErrorEnabled() )

             {

                 getLogger().error( "Could not create regexps to parse Perforce descriptions", ignored );

             }

         }

     }

     // ----------------------------------------------------------------------

     //

     // ----------------------------------------------------------------------

     public List<ChangeSet> getModifications() throws ScmException

     {

         return entries;

     }

     // ----------------------------------------------------------------------

     // StreamConsumer Implementation

     // ----------------------------------------------------------------------

     /** {@inheritDoc} */

     public void consumeLine( String line )

     {

         switch ( status )

         {

             case GET_REVISION:

                 processGetRevision( line );

                 break;

             case GET_COMMENT_BEGIN:

                 status = GET_COMMENT;

                 break;

             case GET_COMMENT:

                 processGetComment( line );

                 break;

             case GET_AFFECTED_FILES:

                 processGetAffectedFiles( line );

                 break;

             case GET_FILES_BEGIN:

                 status = GET_FILE;

                 break;

             case GET_FILE:

                 processGetFile( line );

                 break;

             default:

                 throw new IllegalStateException( "Unknown state: " + status );

         }

     }

     // ----------------------------------------------------------------------

     //

     // ----------------------------------------------------------------------

     /**

      * Add a change log entry to the list (if it's not already there)

      * with the given file.

      *

      * @param entry a {@link ChangeSet} to be added to the list if another

      *              with the same key (p4 change number) doesn't exist already.

      * @param file  a {@link ChangeFile} to be added to the entry

      */

     private void addEntry( ChangeSet entry, ChangeFile file )

     {

         entry.addFile( file );

     }

     /**

      * Each file matches the fileRegexp.

      *

      * @param line A line of text from the Perforce log output

      */

     private void processGetFile( String line )

     {

         if ( line.equals( CHANGELIST_DELIMITER ) ) {

             entries.add( 0, currentChange );

             status = GET_REVISION;

             return;

         }

         if ( !fileRegexp.match( line ) )

         {

             return;

         }

         currentFile = fileRegexp.getParen( 1 );

         // Although Perforce allows files to be submitted anywhere in the

         // repository in a single changelist, we're only concerned about the

         // local files.

         if( currentFile.startsWith( repoPath ) ) {

             currentFile = currentFile.substring( repoPath.length() + 1 );

             addEntry( currentChange, new ChangeFile( currentFile, fileRegexp.getParen( 2 ) ) );

         }

     }

     /**

      * Most of the relevant info is on the revision line matching the

      * 'pattern' string.

      *

      * @param line A line of text from the perforce log output

      */

     private void processGetRevision( String line )

     {

         if ( !revisionRegexp.match( line ) )

         {

             return;

         }

         currentChange = new ChangeSet();

         currentRevision = revisionRegexp.getParen( 1 );

         currentChange.setAuthor( revisionRegexp.getParen( 2 ) );

         currentChange.setDate( revisionRegexp.getParen( 3 ), userDatePattern );

         status = GET_COMMENT_BEGIN;

     }

     /**

      * Process the current input line in the GET_COMMENT state.  This

      * state gathers all of the comments that are part of a log entry.

      *

      * @param line a line of text from the perforce log output

      */

     private void processGetComment( String line )

     {

         if ( line.equals( COMMENT_DELIMITER ) )

         {

             status = GET_AFFECTED_FILES;

         }

         else

         {

             // remove prepended tab

             currentChange.setComment( currentChange.getComment() + line.substring(1) + "\n" );

         }

     }

     /**

      * Process the current input line in the GET_COMMENT state.  This

      * state gathers all of the comments that are part of a log entry.

      *

      * @param line a line of text from the perforce log output

      */

     private void processGetAffectedFiles( String line )

     {

         if ( !line.equals( "Affected files ..." ) )

         {

             return;

         }

         status = GET_FILES_BEGIN;

     }

 }