package org.apache.maven.scm.provider.git.gitexe.command.update;
   
   /*
    * 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.io.File;
  
  import org.apache.maven.scm.ScmBranch;
  import org.apache.maven.scm.ScmException;
  import org.apache.maven.scm.ScmFileSet;
  import org.apache.maven.scm.ScmVersion;
  import org.apache.maven.scm.command.changelog.ChangeLogCommand;
  import org.apache.maven.scm.command.update.AbstractUpdateCommand;
  import org.apache.maven.scm.command.update.UpdateScmResult;
  import org.apache.maven.scm.command.update.UpdateScmResultWithRevision;
  import org.apache.maven.scm.provider.ScmProviderRepository;
  import org.apache.maven.scm.provider.git.command.GitCommand;
  import org.apache.maven.scm.provider.git.gitexe.command.GitCommandLineUtils;
  import org.apache.maven.scm.provider.git.gitexe.command.changelog.GitChangeLogCommand;
  import org.apache.maven.scm.provider.git.gitexe.command.diff.GitDiffCommand;
  import org.apache.maven.scm.provider.git.gitexe.command.diff.GitDiffRawConsumer;
  import org.apache.maven.scm.provider.git.repository.GitScmProviderRepository;
  import org.codehaus.plexus.util.cli.CommandLineUtils;
  import org.codehaus.plexus.util.cli.Commandline;
  
  /**
   * @author Olivier Lamy
   * @author <a href="mailto:struberg@yahoo.de">struberg</a>
   * @since 10 august 2008
   *
   */
  public class GitUpdateCommand
      extends AbstractUpdateCommand
      implements GitCommand
  {
      /** {@inheritDoc} */
      protected UpdateScmResult executeUpdateCommand( ScmProviderRepository repo, ScmFileSet fileSet,
                                                      ScmVersion scmVersion )
          throws ScmException
      {
          GitScmProviderRepository repository = (GitScmProviderRepository) repo;
  
          if ( GitScmProviderRepository.PROTOCOL_FILE.equals( repository.getFetchInfo().getProtocol() )
              && repository.getFetchInfo().getPath().indexOf( fileSet.getBasedir().getPath() ) >= 0 )
          {
              throw new ScmException( "remote repository must not be the working directory" );
          }
  
          int exitCode;
  
          CommandLineUtils.StringStreamConsumer stdout = new CommandLineUtils.StringStreamConsumer();
          CommandLineUtils.StringStreamConsumer stderr = new CommandLineUtils.StringStreamConsumer();
  
          // fir we need to get the current reversion
          Commandline clRev = createLatestRevisionCommandLine( repository, fileSet.getBasedir(), scmVersion );
          GitLatestRevisionCommandConsumer consumerRev = new GitLatestRevisionCommandConsumer( getLogger() );
          exitCode = GitCommandLineUtils.execute( clRev, consumerRev, stderr, getLogger() );
          if ( exitCode != 0 )
          {
              return new UpdateScmResult( clRev.toString(), "The git-log command failed.",
                      stderr.getOutput(), false );
          }
          String origSha1 = consumerRev.getLatestRevision();
  
          Commandline cl = createCommandLine( repository, fileSet.getBasedir(), scmVersion );
          exitCode = GitCommandLineUtils.execute( cl, stdout, stderr, getLogger() );
          if ( exitCode != 0 )
          {
              return new UpdateScmResult( cl.toString(), "The git-pull command failed.",
                                          stderr.getOutput(), false );
          }
  
          // we also need to log exactly what has been updated
          GitDiffRawConsumer diffRawConsumer = new GitDiffRawConsumer( getLogger() );
          Commandline clDiffRaw = GitDiffCommand.createDiffRawCommandLine( fileSet.getBasedir(), origSha1 );
          exitCode = GitCommandLineUtils.execute( clDiffRaw, diffRawConsumer, stderr, getLogger() );
          if ( exitCode != 0 )
          {
              return new UpdateScmResult( clDiffRaw.toString(), "The git-diff --raw command failed.",
                      stderr.getOutput(), false );
          }
  
          
         // now let's get the latest version
         consumerRev = new GitLatestRevisionCommandConsumer( getLogger() );
         exitCode = GitCommandLineUtils.execute( clRev, consumerRev, stderr, getLogger() );
         if ( exitCode != 0 )
         {
             return new UpdateScmResult( clRev.toString(), "The git-log command failed.",
                                         stderr.getOutput(), false );
         }
         String latestRevision = consumerRev.getLatestRevision();
         
         return new UpdateScmResultWithRevision( cl.toString(), diffRawConsumer.getChangedFiles(), latestRevision );
     }
 
     /** {@inheritDoc} */
     protected ChangeLogCommand getChangeLogCommand()
     {
         GitChangeLogCommand changelogCmd = new GitChangeLogCommand();
         changelogCmd.setLogger( getLogger() );
         
         return changelogCmd;
     }
     
     /**
      * create the command line for updating the current branch with the info from the foreign repository. 
      */
     public static Commandline createCommandLine( GitScmProviderRepository repository, File workingDirectory,
                                                  ScmVersion scmVersion )
     {
         Commandline cl = GitCommandLineUtils.getBaseGitCommandLine( workingDirectory, "pull" );
         
         cl.createArg().setLine( repository.getFetchUrl() );
 
         // now set the branch where we would like to pull from
         if ( scmVersion instanceof ScmBranch )
         {
             cl.createArg().setLine( scmVersion.getName() );
         }
         else
         {
             cl.createArg().setLine( "master" );
         }            
         
         return cl;
     }
     
     /**
      * @param scmVersion a valid branch or <code>null</code> if the master branch should be taken
      * @return CommandLine for getting the latest commit on the given branch
      */
     public static Commandline createLatestRevisionCommandLine( GitScmProviderRepository repository,
                                                                File workingDirectory, ScmVersion scmVersion )
     {
         Commandline cl = GitCommandLineUtils.getBaseGitCommandLine( workingDirectory, "log" );
         
         // only show exactly 1 commit
         cl.createArg().setValue( "-n1" ); 
         
         // same as --topo-order, but ensure ordering of merges
         cl.createArg().setValue( "--date-order" );
         
         if ( scmVersion != null && scmVersion instanceof ScmBranch && scmVersion.getName() != null
             && scmVersion.getName().length() > 0 )
         {
             // if any branch is given, lets take em
             cl.createArg().setValue( scmVersion.getName() );
         }
         else
         {
             // otherwise we work on the master branch
             cl.createArg().setValue( "master" );
         }
         
         return cl;
     }
 }