package org.apache.maven.scm.provider.git.gitexe.command.diff;
   
   /*
    * 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 org.apache.maven.scm.ScmException;
  import org.apache.maven.scm.ScmFileSet;
  import org.apache.maven.scm.ScmVersion;
  import org.apache.maven.scm.command.diff.AbstractDiffCommand;
  import org.apache.maven.scm.command.diff.DiffScmResult;
  import org.apache.maven.scm.provider.ScmProviderRepository;
  import org.apache.maven.scm.provider.git.command.GitCommand;
  import org.apache.maven.scm.provider.git.command.diff.GitDiffConsumer;
  import org.apache.maven.scm.provider.git.gitexe.command.GitCommandLineUtils;
  import org.codehaus.plexus.util.StringUtils;
  import org.codehaus.plexus.util.cli.CommandLineUtils;
  import org.codehaus.plexus.util.cli.Commandline;
  
  import java.io.File;
  
  /**
   * @author <a href="mailto:struberg@yahoo.de">Mark Struberg</a>
   *
   */
  public class GitDiffCommand
      extends AbstractDiffCommand
      implements GitCommand
  {
      /** {@inheritDoc} */
      protected DiffScmResult executeDiffCommand( ScmProviderRepository repo, ScmFileSet fileSet,
                                                  ScmVersion startVersion, ScmVersion endVersion )
          throws ScmException
      {
          GitDiffConsumer consumer = new GitDiffConsumer( getLogger(), fileSet.getBasedir() );
          CommandLineUtils.StringStreamConsumer stderr = new CommandLineUtils.StringStreamConsumer();
          int exitCode;
  
          Commandline clDiff2Index = createCommandLine( fileSet.getBasedir(), startVersion, endVersion, false );
  
          exitCode = GitCommandLineUtils.execute( clDiff2Index, consumer, stderr, getLogger() );
          if ( exitCode != 0 )
          {
              return new DiffScmResult( clDiff2Index.toString(), "The git-diff command failed.", stderr.getOutput(),
                                        false );
          }
  
          Commandline clDiff2Head = createCommandLine( fileSet.getBasedir(), startVersion, endVersion, true );
  
          exitCode = GitCommandLineUtils.execute( clDiff2Head, consumer, stderr, getLogger() );
          if ( exitCode != 0 )
          {
              return new DiffScmResult( clDiff2Head.toString(), "The git-diff command failed.", stderr.getOutput(), false );
          }
  
          return new DiffScmResult( clDiff2Index.toString(), consumer.getChangedFiles(), consumer.getDifferences(),
                                    consumer.getPatch() );
      }
  
      // ----------------------------------------------------------------------
      //
      // ----------------------------------------------------------------------
  
      /**
       * @param cached if <code>true</code> diff the index to the head, else diff the tree to the index
       */
      public static Commandline createCommandLine( File workingDirectory, ScmVersion startVersion, ScmVersion endVersion,
                                                   boolean cached )
      {
          Commandline cl = GitCommandLineUtils.getBaseGitCommandLine( workingDirectory, "diff" );
  
          if ( cached )
          {
              cl.createArg().setValue( "--cached" );
          }
  
          if ( startVersion != null && StringUtils.isNotEmpty( startVersion.getName() ) )
          {
              cl.createArg().setValue( startVersion.getName() );
          }
          if ( endVersion != null && StringUtils.isNotEmpty( endVersion.getName() ) )
          {
              cl.createArg().setValue( endVersion.getName() );
          }
 
         return cl;
     }
 
     /**
      * Create a CommandLine for executing a git diff --raw command.
      * This will output all affected files affected since the given commit and
      * the current version.
      *
      * @param workingDirectory
      */
     public static Commandline createDiffRawCommandLine( File workingDirectory, String sha1 )
     {
         Commandline cl = GitCommandLineUtils.getBaseGitCommandLine( workingDirectory, "diff" );
 
         cl.createArg().setValue( "--raw" );
         cl.createArg().setValue( sha1 );
 
         return cl;
     }
 
 }