/**
    * This file Copyright (c) 2003-2014 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 info.magnolia.cms.util.RequestHeaderUtil;
  import info.magnolia.cms.util.ServletUtils;
  import info.magnolia.voting.Voter;
  import info.magnolia.voting.Voting;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.regex.Pattern;
  
  import javax.inject.Inject;
  import javax.servlet.FilterChain;
  import javax.servlet.FilterConfig;
  import javax.servlet.ServletException;
  import javax.servlet.ServletRequest;
  import javax.servlet.ServletResponse;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.lang.ArrayUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * A magnolia filter configured in the config repository. This filter is bypassable.
   * @author philipp
   * @version $Id$
   */
  public abstract class AbstractMgnlFilter implements MgnlFilter {
  
      private static final Logger log = LoggerFactory.getLogger(AbstractMgnlFilter.class);
  
      private String name;
  
      private Voter[] bypasses = new Voter[0];
  
      private boolean enabled = true;
  
      private DispatchRules dispatching = new DispatchRules();
  
      private Mapping mapping = new Mapping();
  
      @Inject
      private WebContainerResources webContainerResources;
  
      protected AbstractMgnlFilter() {
      }
  
      @Override
      public void init(FilterConfig filterConfig) throws ServletException {
      }
  
      @Override
      public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
          doFilter((HttpServletRequest) request, (HttpServletResponse) response, chain);
      }
  
      public abstract void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException;
  
      @Override
      public boolean matches(HttpServletRequest request) {
          return isEnabled() && matchesDispatching(request) && mapsTo(request) && !bypasses(request);
      }
 
     protected boolean mapsTo(HttpServletRequest request) {
         if(getMapping().getMappings().isEmpty()){
             return true;
         }
         return getMapping().match(request).isMatching();
     }
 
     protected boolean matchesDispatching(HttpServletRequest request) {
         if(webContainerResources == null){
             return true;
         }
         boolean toWebContainerResource = webContainerResources.isWebContainerResource(request);
         boolean toMagnoliaResource = !toWebContainerResource;
 
         DispatchRule dispatchRule = getDispatching().getDispatchRule(ServletUtils.getDispatcherType(request));
         if (toMagnoliaResource && dispatchRule.isToMagnoliaResources()) {
             return true;
         }
         if (toWebContainerResource && dispatchRule.isToWebContainerResources()) {
             return true;
         }
         return false;
     }
 
     protected boolean bypasses(HttpServletRequest request) {
         Voting voting = Voting.HIGHEST_LEVEL;
         if (voting.vote(bypasses, request) > 0) {
             return true;
         }
 
         return false;
     }
 
     @Override
     public void destroy() {
         // nothing to do here
     }
 
     public Voter[] getBypasses() {
         return this.bypasses;
     }
 
     public void addBypass(Voter voter) {
         this.bypasses = (Voter[]) ArrayUtils.add(this.bypasses, voter);
     }
 
     @Override
     public String getName() {
         return this.name;
     }
 
     @Override
     public void setName(String name) {
         this.name = name;
     }
 
     public boolean isEnabled() {
         return this.enabled;
     }
 
     public void setEnabled(boolean enabled) {
         this.enabled = enabled;
     }
 
     public DispatchRules getDispatching() {
         return dispatching;
     }
 
     public void setDispatching(DispatchRules dispatching) {
         this.dispatching = dispatching;
     }
 
     public Collection<String> getMappings() {
         ArrayList<String> result = new ArrayList<String>();
         for (Pattern pattern : getMapping().getMappings()) {
             result.add(pattern.pattern());
         }
         return result;
     }
 
     protected Mapping getMapping() {
         return mapping;
     }
 
     public void addMapping(String mapping){
         this.getMapping().addMapping(mapping);
     }
 
     //---- utility methods -----
     protected boolean acceptsGzipEncoding(HttpServletRequest request) {
         return RequestHeaderUtil.acceptsGzipEncoding(request);
     }
 
     protected boolean acceptsEncoding(final HttpServletRequest request, final String name) {
         return RequestHeaderUtil.acceptsEncoding(request, name);
     }
 
     protected boolean headerContains(final HttpServletRequest request, final String header, final String value) {
         return RequestHeaderUtil.headerContains(request, header, value);
     }
 
     protected void addAndVerifyHeader(HttpServletResponse response, String name, String value) {
         RequestHeaderUtil.addAndVerifyHeader(response, name, value);
     }
 
 
 
 }