/*
    * 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.jgit.command.tag;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.maven.scm.ScmException;
  import org.apache.maven.scm.ScmFile;
  import org.apache.maven.scm.ScmFileSet;
  import org.apache.maven.scm.ScmFileStatus;
  import org.apache.maven.scm.ScmResult;
  import org.apache.maven.scm.ScmTagParameters;
  import org.apache.maven.scm.command.tag.AbstractTagCommand;
  import org.apache.maven.scm.command.tag.TagScmResult;
  import org.apache.maven.scm.provider.ScmProviderRepository;
  import org.apache.maven.scm.provider.git.command.GitCommand;
  import org.apache.maven.scm.provider.git.jgit.command.JGitUtils;
  import org.apache.maven.scm.provider.git.repository.GitScmProviderRepository;
  import org.eclipse.jgit.api.Git;
  import org.eclipse.jgit.lib.Constants;
  import org.eclipse.jgit.lib.Ref;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.eclipse.jgit.revwalk.RevWalk;
  import org.eclipse.jgit.transport.RefSpec;
  import org.eclipse.jgit.treewalk.TreeWalk;
  
  /**
   * @author <a href="mailto:struberg@yahoo.de">Mark Struberg</a>
   * @author Dominik Bartholdi (imod)
   * @since 1.9
   */
  public class JGitTagCommand extends AbstractTagCommand implements GitCommand {
  
      public ScmResult executeTagCommand(ScmProviderRepository repo, ScmFileSet fileSet, String tag, String message)
              throws ScmException {
          return executeTagCommand(repo, fileSet, tag, new ScmTagParameters(message));
      }
  
      /**
       * {@inheritDoc}
       */
      public ScmResult executeTagCommand(
              ScmProviderRepository repo, ScmFileSet fileSet, String tag, ScmTagParameters scmTagParameters)
              throws ScmException {
          if (tag == null || tag.trim().isEmpty()) {
              throw new ScmException("tag name must be specified");
          }
  
          if (!fileSet.getFileList().isEmpty()) {
              throw new ScmException("This provider doesn't support tagging subsets of a directory");
          }
  
          String escapedTagName = tag.trim().replace(' ', '_');
  
          Git git = null;
          try {
              git = JGitUtils.openRepo(fileSet.getBasedir());
  
              // tag the revision
              String tagMessage = scmTagParameters.getMessage();
              Ref tagRef = git.tag()
                      .setName(escapedTagName)
                      .setMessage(tagMessage)
                      .setForceUpdate(false)
                      .call();
  
              if (repo.isPushChanges()) {
                  logger.info("push tag [" + escapedTagName + "] to remote...");
                  JGitUtils.push(git, (GitScmProviderRepository) repo, new RefSpec(Constants.R_TAGS + escapedTagName));
              }
  
              // search for the tagged files
              RevWalk revWalk = new RevWalk(git.getRepository());
              RevCommit commit = revWalk.parseCommit(tagRef.getObjectId());
              revWalk.close();
  
              final TreeWalk walk = new TreeWalk(git.getRepository());
              walk.reset(); // drop the first empty tree, which we do not need here
              walk.setRecursive(true);
              walk.addTree(commit.getTree());
  
              List<ScmFile> taggedFiles = new ArrayList<>();
             while (walk.next()) {
                 taggedFiles.add(new ScmFile(walk.getPathString(), ScmFileStatus.CHECKED_OUT));
             }
             walk.close();
 
             return new TagScmResult("JGit tag", taggedFiles);
         } catch (Exception e) {
             throw new ScmException("JGit tag failure!", e);
         } finally {
             JGitUtils.closeRepo(git);
         }
     }
 }