/*
    * 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.spi.impl;
  
  import java.lang.reflect.InvocationTargetException;
  import java.security.AccessController;
  import java.security.PrivilegedActionException;
  import java.security.PrivilegedExceptionAction;
  import java.util.List;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  import javax.faces.FacesException;
  import javax.faces.context.ExternalContext;
  import org.apache.myfaces.application.viewstate.StateCacheFactoryImpl;
  import org.apache.myfaces.shared.util.ClassUtils;
  import org.apache.myfaces.spi.ServiceProviderFinderFactory;
  import org.apache.myfaces.spi.StateCacheProvider;
  import org.apache.myfaces.spi.StateCacheProviderFactory;
  
  /**
   *
   */
  public class DefaultStateCacheProviderFactory extends StateCacheProviderFactory
  {
      
      public static final String STATE_CACHE_PROVIDER = StateCacheProvider.class.getName();
      
      public static final String STATE_CACHE_PROVIDER_LIST = StateCacheProvider.class.getName()+".LIST";
      
      public static final String STATE_CACHE_PROVIDER_INSTANCE = StateCacheProvider.class.getName()+".INSTANCE";
      
      private Logger getLogger()
      {
          return Logger.getLogger(DefaultStateCacheProviderFactory.class.getName());
      }
      
      @Override
      public StateCacheProvider getStateCacheProvider(ExternalContext externalContext)
      {
          StateCacheProvider stateCacheProvider
                  = (StateCacheProvider) externalContext.getApplicationMap().get(STATE_CACHE_PROVIDER_INSTANCE);
          if (stateCacheProvider == null)
          {
              stateCacheProvider = createStateCacheProvider(externalContext);
              externalContext.getApplicationMap().put(STATE_CACHE_PROVIDER_INSTANCE, stateCacheProvider);
          }
          return stateCacheProvider;
      }
      
      @Override
      public StateCacheProvider createStateCacheProvider(
              ExternalContext externalContext)
      {
          StateCacheProvider returnValue = null;
          final ExternalContext extContext = externalContext;
          try
          {
              if (System.getSecurityManager() != null)
              {
                  returnValue = AccessController.doPrivileged(new PrivilegedExceptionAction<StateCacheProvider>()
                          {
                              public StateCacheProvider run() throws ClassNotFoundException,
                                      NoClassDefFoundError,
                                      InstantiationException,
                                      IllegalAccessException,
                                      InvocationTargetException,
                                      PrivilegedActionException
                              {
                                  return resolveStateCacheProviderFromService(extContext);
                              }
                          });
              }
              else
              {
                  returnValue = resolveStateCacheProviderFromService(extContext);
              }
          }
          catch (ClassNotFoundException e)
          {
              // ignore
          }
          catch (NoClassDefFoundError e)
          {
             // ignore
         }
         catch (InstantiationException e)
         {
             getLogger().log(Level.SEVERE, "", e);
         }
         catch (IllegalAccessException e)
         {
             getLogger().log(Level.SEVERE, "", e);
         }
         catch (InvocationTargetException e)
         {
             getLogger().log(Level.SEVERE, "", e);
         }
         catch (PrivilegedActionException e)
         {
             throw new FacesException(e);
         }
         return returnValue;
     }
     
     private StateCacheProvider resolveStateCacheProviderFromService(
             ExternalContext externalContext) throws ClassNotFoundException,
             NoClassDefFoundError,
             InstantiationException,
             IllegalAccessException,
             InvocationTargetException,
             PrivilegedActionException
     {
         List<String> classList = (List<String>) externalContext.getApplicationMap().get(STATE_CACHE_PROVIDER_LIST);
         if (classList == null)
         {
             classList = ServiceProviderFinderFactory.getServiceProviderFinder(externalContext).
                     getServiceProviderList(STATE_CACHE_PROVIDER);
             externalContext.getApplicationMap().put(STATE_CACHE_PROVIDER_LIST, classList);
         }
         return ClassUtils.buildApplicationObject(StateCacheProvider.class, classList, new StateCacheFactoryImpl());
     }    
     
 }