/*
    * 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 org.apache.myfaces.config.DefaultFacesConfigurationProvider;
  import org.apache.myfaces.shared.util.ClassUtils;
  import org.apache.myfaces.spi.FacesConfigurationProvider;
  import org.apache.myfaces.spi.FacesConfigurationProviderFactory;
  import org.apache.myfaces.spi.ServiceProviderFinderFactory;
  
  import javax.faces.FacesException;
  import javax.faces.context.ExternalContext;
  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;
  
  /**
   * 
   * @author Leonardo Uribe
   * @since 2.0.3
   */
  public class DefaultFacesConfigurationProviderFactory extends FacesConfigurationProviderFactory
  {
  
      public static final String FACES_CONFIGURATION_PROVIDER = FacesConfigurationProvider.class.getName();
      
      public static final String FACES_CONFIGURATION_PROVIDER_LIST = FacesConfigurationProvider.class.getName()+".LIST";
      
      public static final String FACES_CONFIGURATION_PROVIDER_INSTANCE_KEY
              = FacesConfigurationProvider.class.getName() + ".INSTANCE";
  
      private Logger getLogger()
      {
          return Logger.getLogger(DefaultFacesConfigurationProviderFactory.class.getName());
      }
  
      @Override
      public FacesConfigurationProvider getFacesConfigurationProvider(
              ExternalContext externalContext)
      {
          FacesConfigurationProvider returnValue = (FacesConfigurationProvider)
                  externalContext.getApplicationMap().get(FACES_CONFIGURATION_PROVIDER_INSTANCE_KEY);
          if (returnValue == null)
          {
              final ExternalContext extContext = externalContext;
              try
              {
                  if (System.getSecurityManager() != null)
                  {
                      returnValue
                              = AccessController.doPrivileged(new PrivilegedExceptionAction<FacesConfigurationProvider>()
                              {
                                  public FacesConfigurationProvider run() throws ClassNotFoundException,
                                          NoClassDefFoundError,
                                          InstantiationException,
                                          IllegalAccessException,
                                          InvocationTargetException,
                                          PrivilegedActionException
                                  {
                                      return resolveFacesConfigurationProviderFromService(extContext);
                                  }
                              });
                  }
                  else
                  {
                      returnValue = resolveFacesConfigurationProviderFromService(extContext);
                  }
                  externalContext.getApplicationMap().put(FACES_CONFIGURATION_PROVIDER_INSTANCE_KEY, returnValue);
              }
              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 FacesConfigurationProvider resolveFacesConfigurationProviderFromService(
             ExternalContext externalContext) throws ClassNotFoundException,
             NoClassDefFoundError,
             InstantiationException,
             IllegalAccessException,
             InvocationTargetException,
             PrivilegedActionException
     {
         List<String> classList = (List<String>)
                 externalContext.getApplicationMap().get(FACES_CONFIGURATION_PROVIDER_LIST);
         if (classList == null)
         {
             classList = ServiceProviderFinderFactory.getServiceProviderFinder(externalContext).
                     getServiceProviderList(FACES_CONFIGURATION_PROVIDER);
             externalContext.getApplicationMap().put(FACES_CONFIGURATION_PROVIDER_LIST, classList);
         }
 
         return ClassUtils.buildApplicationObject(FacesConfigurationProvider.class, classList,
                                                  new DefaultFacesConfigurationProvider());
     }
 }