package org.apache.maven.scm.plugin;
   
   /*
    * 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.plugin.MojoExecutionException;
  import org.apache.maven.plugins.annotations.Mojo;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.scm.ScmException;
  import org.apache.maven.scm.command.diff.DiffScmResult;
  import org.apache.maven.scm.repository.ScmRepository;
  import org.codehaus.plexus.util.FileUtils;
  
  import java.io.File;
  import java.io.IOException;
  
  /**
   * Display the difference of the working copy with the latest copy in the configured scm url.
   *
   * @author <a href="evenisse@apache.org">Emmanuel Venisse</a>
   */
  @Mojo( name = "diff", aggregator = true )
  public class DiffMojo
      extends AbstractScmMojo
  {
      /**
       * The version type (branch/tag/revision) of scmVersion.
       */
      @Parameter( property = "startScmVersionType" )
      private String startScmVersionType;
  
      /**
       * The version (revision number/branch name/tag name).
       */
      @Parameter( property = "startScmVersion" )
      private String startScmVersion;
  
      /**
       * The version type (branch/tag/revision) of scmVersion.
       */
      @Parameter( property = "endScmVersionType" )
      private String endScmVersionType;
  
      /**
       * The version (revision number/branch name/tag name).
       */
      @Parameter( property = "endScmVersion" )
      private String endScmVersion;
  
      /**
       * Output file name.
       */
      @Parameter( property = "outputFile", defaultValue = "${project.artifactId}.diff" )
      private File outputFile;
  
      /** {@inheritDoc} */
      public void execute()
          throws MojoExecutionException
      {
          super.execute();
  
          try
          {
              ScmRepository repository = getScmRepository();
  
              DiffScmResult result = getScmManager().diff( repository, getFileSet(),
                                                           getScmVersion( startScmVersionType, startScmVersion ),
                                                           getScmVersion( endScmVersionType, endScmVersion ) );
  
              checkResult( result );
  
              getLog().info( result.getPatch() );
  
              try
              {
                  if ( outputFile != null )
                  {
                      FileUtils.fileWrite( outputFile.getAbsolutePath(), result.getPatch() );
                  }
              }
              catch ( IOException e )
              {
                  throw new MojoExecutionException( "Can't write patch file.", e );
             }
         }
         catch ( IOException e )
         {
             throw new MojoExecutionException( "Cannot run diff command : ", e );
         }
         catch ( ScmException e )
         {
             throw new MojoExecutionException( "Cannot run diff command : ", e );
         }
     }
 }