/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.myfaces.webapp.filter;
  
  import java.io.IOException;
  
  import javax.servlet.Filter;
  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.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.myfaces.shared_tomahawk.renderkit.html.util.JavascriptUtils;
  
  
  /**
   *
   * Filter to handle javascript detection redirect. This is an EXPERIMENTAL feature.
   *
   * @author Oliver Rossmueller (latest modification by $Author: grantsmith $)
   *
   */
  public class JavaScriptDetectorFilter implements Filter
  {
      private static final Log log = LogFactory.getLog(JavaScriptDetectorFilter.class);
  
      public void init(FilterConfig filterConfig) throws ServletException
      {
      }
  
      public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException
      {
          HttpServletRequest request = (HttpServletRequest) servletRequest;
          HttpServletResponse response = (HttpServletResponse) servletResponse;
  
          JavascriptUtils.setJavascriptDetected(request.getSession(true), true); // mark the session to use javascript
  
          String redirectURL = response.encodeRedirectURL(request.getParameter("goto"));
          log.info("Enabled JavaScript for session - redirect to " + redirectURL);
          response.sendRedirect(redirectURL);
      }
  
      public void destroy()
      {
      }
  }