/**
 * Copyright (c) 2010, Sebastian Sdorra
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. Neither the name of SCM-Manager; nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * http://bitbucket.org/sdorra/scm-manager
 *
 */



package sonia.scm.repository.spi;

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

import com.google.common.base.Strings;
import com.google.common.collect.Lists;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.tmatesoft.svn.core.SVNException;
import org.tmatesoft.svn.core.SVNLogEntry;
import org.tmatesoft.svn.core.io.SVNRepository;

import sonia.scm.repository.Changeset;
import sonia.scm.repository.ChangesetPagingResult;
import sonia.scm.repository.Repository;
import sonia.scm.repository.RepositoryException;
import sonia.scm.repository.SvnUtil;
import sonia.scm.util.Util;

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

import java.io.IOException;

import java.util.Collection;
import java.util.List;

/**
 *
 * @author Sebastian Sdorra
 */
public class SvnLogCommand extends AbstractSvnCommand implements LogCommand
{

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

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

  /**
   * Constructs ...
   *
   *
   *
   * @param context
   * @param repository
   * @param repositoryDirectory
   */
  SvnLogCommand(SvnContext context, Repository repository)
  {
    super(context, repository);
  }

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

  /**
   * Method description
   *
   *
   * @param revision
   *
   * @return
   *
   * @throws IOException
   * @throws RepositoryException
   */
  @Override
  public Changeset getChangeset(String revision)
    throws IOException, RepositoryException
  {
    Changeset changeset = null;

    if (logger.isDebugEnabled())
    {
      logger.debug("fetch changeset {}", revision);
    }

    try
    {
      long revisioNumber = Long.parseLong(revision);
      SVNRepository repository = open();
      Collection<SVNLogEntry> entries = repository.log(null, null,
                                          revisioNumber, revisioNumber, true,
                                          true);

      if (Util.isNotEmpty(entries))
      {
        changeset = SvnUtil.createChangeset(entries.iterator().next());
      }
    }
    catch (NumberFormatException ex)
    {
      throw new RepositoryException("could not convert revision", ex);
    }
    catch (SVNException ex)
    {
      throw new RepositoryException("could not open repository", ex);
    }

    return changeset;
  }

  /**
   * Method description
   *
   *
   * @param request
   *
   * @return
   *
   * @throws IOException
   * @throws RepositoryException
   */
  @Override
  public ChangesetPagingResult getChangesets(LogCommandRequest request)
    throws IOException, RepositoryException
  {
    if (logger.isDebugEnabled())
    {
      logger.debug("fetch changesets for {}", request);
    }

    ChangesetPagingResult changesets = null;
    String startRevision = request.getStartChangeset();
    String endRevision = request.getEndChangeset();

    try
    {
      SVNRepository repository = open();
      long startRev = repository.getLatestRevision();
      long endRev = 0;
      long maxRev = startRev;

      if (!Strings.isNullOrEmpty(startRevision))
      {
        startRev = Long.parseLong(startRevision);
      }

      if (!Strings.isNullOrEmpty(endRevision))
      {
        endRev = Long.parseLong(endRevision);
      }

      String[] pathArray = null;

      if (!Strings.isNullOrEmpty(request.getPath()))
      {
        pathArray = new String[] { request.getPath() };
      }

      List<SVNLogEntry> changesetList = Lists.newArrayList();
      Collection<SVNLogEntry> entries = repository.log(pathArray, null,
                                          startRev, endRev, true, true);

      for (SVNLogEntry entry : entries)
      {
        if (entry.getRevision() <= maxRev)
        {
          changesetList.add(entry);
        }
      }

      int total = changesetList.size();
      int start = request.getPagingStart();
      int max = request.getPagingLimit() + start;
      int end = total;

      if ((max > 0) && (end > max))
      {
        end = max;
      }

      if (start < 0)
      {
        start = 0;
      }

      if (logger.isTraceEnabled())
      {
        logger.trace(
          "create sublist from {} to {} of total {} collected changesets",
          start, end, total);
      }

      changesetList = changesetList.subList(start, end);
      changesets = new ChangesetPagingResult(total,
        SvnUtil.createChangesets(changesetList));
    }
    catch (NumberFormatException ex)
    {
      throw new RepositoryException(
        "could not parse revision ".concat(startRevision), ex);
    }
    catch (SVNException ex)
    {
      throw new RepositoryException("could not open repository", ex);
    }

    return changesets;
  }
}
