/*
    * 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.lifecycle;
  
  import java.util.HashMap;
  import java.util.Map;
  import javax.faces.context.FacesContext;
  import javax.faces.event.ExceptionQueuedEvent;
  import javax.faces.event.ExceptionQueuedEventContext;
  import javax.faces.event.PhaseEvent;
  import javax.faces.event.PhaseId;
  import javax.faces.event.PhaseListener;
  import javax.faces.lifecycle.Lifecycle;
  
  /**
   * This class encapsulates the logic used to call PhaseListeners. It was needed because of issue 9 of the JSF 1.2 spec.
   * See section 11.3 for more details.
   * 
   * @author Stan Silvert
   */
  class PhaseListenerManager
  {
      private Lifecycle lifecycle;
      private FacesContext facesContext;
      private PhaseListener[] phaseListeners;
  
      // Tracks success in the beforePhase. Listeners that throw an exception
      // in beforePhase or were never called because a previous listener threw
      // an exception should not have its afterPhase called
      private Map<PhaseId, boolean[]> listenerSuccessMap = new HashMap<PhaseId, boolean[]>();
  
      /** Creates a new instance of PhaseListenerManager */
      PhaseListenerManager(Lifecycle lifecycle, FacesContext facesContext, PhaseListener[] phaseListeners)
      {
          this.lifecycle = lifecycle;
          this.facesContext = facesContext;
          this.phaseListeners = phaseListeners;
      }
  
      private boolean isListenerForThisPhase(PhaseListener phaseListener, PhaseId phaseId)
      {
          int listenerPhaseId = phaseListener.getPhaseId().getOrdinal();
          return (listenerPhaseId == PhaseId.ANY_PHASE.getOrdinal() || listenerPhaseId == phaseId.getOrdinal());
      }
  
      void informPhaseListenersBefore(PhaseId phaseId)
      {
          boolean[] beforePhaseSuccess = new boolean[phaseListeners.length];
          listenerSuccessMap.put(phaseId, beforePhaseSuccess);
  
          PhaseEvent event = new PhaseEvent(facesContext, phaseId, lifecycle);
  
          for (int i = 0; i < phaseListeners.length; i++)
          {
              PhaseListener phaseListener = phaseListeners[i];
              if (isListenerForThisPhase(phaseListener, phaseId))
              {
                  try
                  {
                      phaseListener.beforePhase(event);
                      beforePhaseSuccess[i] = true;
                  }
                  catch (Throwable e)
                  {
                      beforePhaseSuccess[i] = false; // redundant - for clarity
                      
                      // JSF 2.0: publish exceptions instead of logging them.
                      
                      publishException (e, phaseId, ExceptionQueuedEventContext.IN_BEFORE_PHASE_KEY);
                      
                      return;
                  }
              }
          }
      }
  
      void informPhaseListenersAfter(PhaseId phaseId)
      {
          boolean[] beforePhaseSuccess = listenerSuccessMap.get(phaseId);
          
          if (beforePhaseSuccess == null)
          {
             // informPhaseListenersBefore method was not called : maybe an exception in LifecycleImpl.executePhase  
             return;
         }
 
         PhaseEvent event = null;
 
         for (int i = phaseListeners.length - 1; i >= 0; i--)
         {
             PhaseListener phaseListener = phaseListeners[i];
             if (isListenerForThisPhase(phaseListener, phaseId) && beforePhaseSuccess[i])
             {
                 if (event == null)
                 {
                     event = new PhaseEvent(facesContext, phaseId, lifecycle);
                 }
                 try
                 {
                     phaseListener.afterPhase(event);
                 }
                 catch (Throwable e)
                 {
                     // JSF 2.0: publish exceptions instead of logging them.
                     
                     publishException (e, phaseId, ExceptionQueuedEventContext.IN_AFTER_PHASE_KEY);
                 }
             }
         }
 
     }
     
     private void publishException (Throwable e, PhaseId phaseId, String key)
     {
         ExceptionQueuedEventContext context = new ExceptionQueuedEventContext (facesContext, e, null, phaseId);
         
         context.getAttributes().put (key, Boolean.TRUE);
         
         facesContext.getApplication().publishEvent (facesContext, ExceptionQueuedEvent.class, context);
     }
 }