/*
    * 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.provider.git.gitexe.command.update;
  
  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();
          exitCode = GitCommandLineUtils.execute(clRev, consumerRev, stderr);
          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);
          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();
          Commandline clDiffRaw = GitDiffCommand.createDiffRawCommandLine(fileSet.getBasedir(), origSha1);
          exitCode = GitCommandLineUtils.execute(clDiffRaw, diffRawConsumer, stderr);
          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();
          exitCode = GitCommandLineUtils.execute(clRev, consumerRev, stderr);
          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() {
         return new GitChangeLogCommand();
     }
 
     /**
      * 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());
         }
 
         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 instanceof ScmBranch
                 && scmVersion.getName() != null
                 && scmVersion.getName().length() > 0) {
             // if any branch is given, lets take em
             cl.createArg().setValue(scmVersion.getName());
         }
         // otherwise we work on HEAD/current branch
 
         return cl;
     }
 }