/**
 * 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.web;

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

import com.google.inject.Inject;
import com.google.inject.Singleton;

import org.eclipse.jgit.http.server.GitServlet;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.transport.resolver.RepositoryResolver;

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

import sonia.scm.repository.GitUtil;
import sonia.scm.repository.RepositoryProvider;
import sonia.scm.repository.RepositoryRequestListenerUtil;
import sonia.scm.util.HttpUtil;

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

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author Sebastian Sdorra
 */
@Singleton
public class ScmGitServlet extends GitServlet
{

  /** Field description */
  public static final String REGEX_GITHTTPBACKEND =
    "(?x)^/git/(.*/(HEAD|info/refs|objects/(info/[^/]+|[0-9a-f]{2}/[0-9a-f]{38}|pack/pack-[0-9a-f]{40}\\.(pack|idx))|git-(upload|receive)-pack))$";

  /** Field description */
  private static final long serialVersionUID = -7712897339207470674L;

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

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

  /**
   * Constructs ...
   *
   *
   *
   * @param repositoryResolver
   * @param receivePackFactory
   * @param repositoryProvider
   * @param repositoryRequestListenerUtil
   */
  @Inject
  public ScmGitServlet(
          GitRepositoryResolver repositoryResolver,
          GitReceivePackFactory receivePackFactory,
          RepositoryProvider repositoryProvider,
          RepositoryRequestListenerUtil repositoryRequestListenerUtil)
  {
    this.resolver = repositoryResolver;
    this.repositoryProvider = repositoryProvider;
    this.repositoryRequestListenerUtil = repositoryRequestListenerUtil;
    setRepositoryResolver(repositoryResolver);
    setReceivePackFactory(receivePackFactory);
  }

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

  /**
   * Method description
   *
   *
   * @param request
   * @param response
   *
   * @throws IOException
   * @throws ServletException
   */
  @Override
  protected void service(HttpServletRequest request,
                         HttpServletResponse response)
          throws ServletException, IOException
  {
    String uri = HttpUtil.getStrippedURI(request);

    if (uri.matches(REGEX_GITHTTPBACKEND))
    {
      sonia.scm.repository.Repository repository = repositoryProvider.get();

      if (repository != null)
      {
        if (repositoryRequestListenerUtil.callListeners(request, response,
                repository))
        {
          super.service(request, response);
        }
        else if (logger.isDebugEnabled())
        {
          logger.debug("request aborted by repository request listener");
        }
      }
      else
      {
        super.service(request, response);
      }
    }
    else
    {
      printGitInformation(request, response);
    }
  }

  /**
   * Method description
   *
   *
   *
   * @param request
   * @param response
   *
   * @throws IOException
   * @throws ServletException
   */
  private void printGitInformation(HttpServletRequest request,
                                   HttpServletResponse response)
          throws ServletException, IOException
  {
    sonia.scm.repository.Repository scmRepository = repositoryProvider.get();

    if (scmRepository != null)
    {
      Repository repository = null;

      try
      {
        repository = resolver.open(request, scmRepository.getName());
        new GitRepositoryViewer().handleRequest(response, repository,
                scmRepository.getName());
      }
      catch (Exception ex)
      {
        throw new ServletException(ex);
      }
      finally
      {
        GitUtil.close(repository);
      }
    }
    else
    {
      response.sendError(HttpServletResponse.SC_NOT_FOUND);
    }
  }

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

  /** Field description */
  private RepositoryProvider repositoryProvider;

  /** Field description */
  private RepositoryRequestListenerUtil repositoryRequestListenerUtil;

  /** Field description */
  private RepositoryResolver<HttpServletRequest> resolver;
}