/**
    * This file Copyright (c) 2003-2011 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.cms.filters;
  
  import java.io.IOException;
  import javax.servlet.Filter;
  import javax.servlet.FilterChain;
  import javax.servlet.FilterConfig;
  import javax.servlet.ServletContext;
  import javax.servlet.ServletException;
  import javax.servlet.ServletRequest;
  import javax.servlet.ServletResponse;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import info.magnolia.context.MgnlContext;
  import info.magnolia.objectfactory.Components;
  
  
  /**
   * Entry point for Magnolia filter dispatching. Intercepts all requests and passes them on to the Magnolia filter chain
   * that will either process the request or pass it on to the next filter configured in web.xml.
   *
   * @version $Id$
   * @see FilterManager
   * @see MgnlFilterDispatcher
   */
  public class MgnlMainFilter implements Filter {
  
      private static final Logger log = LoggerFactory.getLogger(MgnlMainFilter.class);
  
      /**
       * @deprecated since 4.5, use {@link FilterManager#SERVER_FILTERS}.
       */
      public static final String SERVER_FILTERS = FilterManager.SERVER_FILTERS;
  
      /**
       * @deprecated since 4.5, use IoC to access FilterManager.
       */
      private static MgnlMainFilter instance;
  
      private FilterManager filterManager;
  
      @Override
      public void init(FilterConfig filterConfig) throws ServletException {
          instance = this;
          filterManager = getFilterManager(filterConfig.getServletContext());
          filterManager.init(filterConfig);
      }
  
      @Override
      public void destroy() {
          if (filterManager != null) {
              filterManager.destroy();
          }
      }
  
      @Override
      public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
          doFilter((HttpServletRequest) request, (HttpServletResponse) response, chain);
      }
  
      public void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
          log.debug("Handling URI: {} - Path info: {}", request.getRequestURI(), request.getPathInfo());
  
         // global fix for MAGNOLIA-3338 to make this independent of other dispatching rules
         boolean contextUpdated = false;
         if (MgnlContext.hasInstance()) {
             MgnlContext.push(request, response);
             contextUpdated = true;
         }
 
         try {
             filterManager.getFilterDispatcher().doDispatch(request, response, chain);
         } finally {
             if (contextUpdated && MgnlContext.hasInstance()) {
                 MgnlContext.pop();
             }
         }
     }
 
     /**
      * Returns the root filter, note that the filter is destroyed if the filter chain is reloaded.
      */
     public MgnlFilter getRootFilter() {
         return filterManager.getFilterDispatcher().getTargetFilter();
     }
 
     protected FilterManager getFilterManager(ServletContext servletContext) {
         return Components.getComponent(FilterManager.class);
     }
 
     /**
      * @deprecated since 4.5, use IoC to access FilterManager.
      */
     public static MgnlMainFilter getInstance() {
         return instance;
     }
 
 }