/*

  * This software is licensed under the Apache License, Version 2.0

  * (the "License") agreement; 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 net.admin4j.ui.filters;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.List;

 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 net.admin4j.deps.commons.lang3.StringUtils;

 /**

  * Standard filter that conveniently invokes all other Admin4J filters in a standard configuration.

  * this exists to make Admin4J easier to configure.

  * 

  * <p>Init parameters for this filter are as follows:</p>

  * <li>include.serverside.timestamp -- Optional.  Default false.  If true, includes a server-side timestamp in all returned html.

  *    Useful if debugging possible performance issues reported only by people in some remote places of the world.</li>

  * @author D. Ashmore

  *

  */

 public class Admin4JStandardFilter extends BaseFilter {

     private List<String> filterKeyList;

     public void destroy() {

         // No Op

     }

     public void doFilter(ServletRequest request, ServletResponse response,

             FilterChain chain) throws IOException, ServletException {

         Admin4JStandardFilterChain localChain = new Admin4JStandardFilterChain(this.findfilterKeyList(), chain);

         localChain.doFilter(request, response);

     }

     private synchronized List<String> findfilterKeyList() {

         if (filterKeyList != null) {

             return filterKeyList;

         }

         List<String> list = new ArrayList<String>();

         if (Admin4JStandardFilterChain.isRegistered(PerformanceMonitoringFilter.class.getName())) {

             list.add(PerformanceMonitoringFilter.class.getName());

         }

         if (Admin4JStandardFilterChain.isRegistered(PerformanceTimeStampingFilter.class.getName())) {

             list.add(PerformanceTimeStampingFilter.class.getName());

         }

         if (Admin4JStandardFilterChain.isRegistered(ConcurrentUsageFilter.class.getName())) {

             list.add(ConcurrentUsageFilter.class.getName());

         }

         if (Admin4JStandardFilterChain.isRegistered(RequestTrackingFilter.class.getName())) {

             list.add(RequestTrackingFilter.class.getName());

         }

         if (Admin4JStandardFilterChain.isRegistered(ErrorNotificationFilter.class.getName())) {

             list.add(ErrorNotificationFilter.class.getName());

         }

         else {

             list.add(ErrorLoggingFilter.class.getName());

         }

         filterKeyList = list;

         return list;

     }

     public void init(FilterConfig config) throws ServletException {

         this.configureFilter(new ErrorLoggingFilter(), config);

         this.configureFilter(new ErrorNotificationFilter(), config);

         this.configureFilter(new PerformanceMonitoringFilter(), config);

         this.configureFilter(new ConcurrentUsageFilter(), config);

         this.configureFilter(new RequestTrackingFilter(), config);

         String includeTimestampingStr = config.getInitParameter("include.serverside.timestamp");

         if ( !StringUtils.isEmpty(includeTimestampingStr) && "true".equalsIgnoreCase(includeTimestampingStr)) {

             this.configureFilter(new PerformanceTimeStampingFilter(), config);

         }

     }

     private void configureFilter(Filter filter, FilterConfig config) {

         if (Admin4JStandardFilterChain.isRegistered(filter.getClass().getName())) {

             return;

         }

         try {

             filter.init(config);

             Admin4JStandardFilterChain.registerFilter(filter, true);

         }

         catch (Throwable t) {

             logger.warn("Error configuring Filter", t);

         }

     }

 }