/*
 * MIT License
 *
 * Copyright (c) 2020-present Cloudogu GmbH and Contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package sonia.scm.repository.spi;

//~--- non-JDK imports --------------------------------------------------------

import com.google.common.base.Function;
import com.google.common.collect.Lists;
import org.eclipse.jgit.api.Git;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevWalk;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import sonia.scm.repository.GitUtil;
import sonia.scm.repository.InternalRepositoryException;
import sonia.scm.repository.Tag;

import java.io.IOException;
import java.util.List;

//~--- JDK imports ------------------------------------------------------------

/**
 *
 * @author Sebastian Sdorra
 */
public class GitTagsCommand extends AbstractGitCommand implements TagsCommand
{

  /**
   * Constructs ...
   *
   *  @param context
   *
   */
  public GitTagsCommand(GitContext context)
  {
    super(context);
  }

  //~--- get methods ----------------------------------------------------------

  @Override
  public List<Tag> getTags() throws IOException
  {
    List<Tag> tags = null;

    RevWalk revWalk = null;

    try
    {
      final Git git = new Git(open());

      revWalk = new RevWalk(git.getRepository());

      List<Ref> tagList = git.tagList().call();

      tags = Lists.transform(tagList,
        new TransformFuntion(git.getRepository(), revWalk));
    }
    catch (GitAPIException ex)
    {
      throw new InternalRepositoryException(repository, "could not read tags from repository", ex);
    }
    finally
    {
      GitUtil.release(revWalk);
    }

    return tags;
  }

  //~--- inner classes --------------------------------------------------------

  /**
   * Class description
   *
   *
   * @version        Enter version here..., 12/07/06
   * @author         Enter your name here...
   */
  private static class TransformFuntion implements Function<Ref, Tag>
  {

    /**
     * the logger for TransformFuntion
     */
    private static final Logger logger =
      LoggerFactory.getLogger(TransformFuntion.class);

    //~--- constructors -------------------------------------------------------

    /**
     * Constructs ...
     *
     *
     * @param repository
     * @param revWalk
     */
    public TransformFuntion(org.eclipse.jgit.lib.Repository repository,
      RevWalk revWalk)
    {
      this.repository = repository;
      this.revWalk = revWalk;
    }

    //~--- methods ------------------------------------------------------------

    /**
     * Method description
     *
     *
     * @param ref
     *
     * @return
     */
    @Override
    public Tag apply(Ref ref)
    {
      Tag tag = null;

      try
      {
        RevCommit commit = GitUtil.getCommit(repository, revWalk, ref);

        if (commit != null)
        {
          String name = GitUtil.getTagName(ref);

          tag = new Tag(name, commit.getId().name());
        }

      }
      catch (IOException ex)
      {
        logger.error("could not get commit for tag", ex);
      }

      return tag;
    }

    //~--- fields -------------------------------------------------------------

    /** Field description */
    private org.eclipse.jgit.lib.Repository repository;

    /** Field description */
    private RevWalk revWalk;
  }
}
