/*
    * 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.
   */
  package org.apache.maven.scm.plugin;
  
  import javax.inject.Inject;
  
  import java.io.File;
  import java.io.IOException;
  
  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.manager.ScmManager;
  import org.apache.maven.scm.repository.ScmRepository;
  import org.apache.maven.settings.crypto.SettingsDecrypter;
  import org.codehaus.plexus.util.FileUtils;
  
  /**
   * 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;
  
      @Inject
      public DiffMojo(ScmManager manager, SettingsDecrypter settingsDecrypter) {
          super(manager, settingsDecrypter);
      }
  
      /**
       * {@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().debug(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 | ScmException e) {
             throw new MojoExecutionException("Cannot run diff command : ", e);
         }
     }
 }