/*

  * 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.PhaseEvent;

 import javax.faces.event.PhaseId;

 import javax.faces.event.PhaseListener;

 import javax.faces.lifecycle.Lifecycle;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 /**

  * 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 static final Log log = LogFactory.getLog(PhaseListenerManager.class);

     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);

         for (int i = 0; i < phaseListeners.length; i++) {

             PhaseListener phaseListener = phaseListeners[i];

             if (isListenerForThisPhase(phaseListener, phaseId)) {

                 try {

                     phaseListener.beforePhase(new PhaseEvent(facesContext, phaseId, lifecycle));

                     beforePhaseSuccess[i] = true;

                 } catch (Exception e) {

                     beforePhaseSuccess[i] = false; // redundant - for clarity

                     log.error("Exception in PhaseListener " + phaseId.toString() + " beforePhase.", e);

                     return;

                 }

             }

         }

     }

     void informPhaseListenersAfter(PhaseId phaseId) {

         boolean[] beforePhaseSuccess = listenerSuccessMap.get(phaseId);

         for (int i = phaseListeners.length - 1; i >= 0; i--)  {

             PhaseListener phaseListener = phaseListeners[i];

             if (isListenerForThisPhase(phaseListener, phaseId) 

                 && beforePhaseSuccess[i]) {

                 try {

                     phaseListener.afterPhase(new PhaseEvent(facesContext, phaseId, lifecycle));

                 } catch (Exception e) {

                     log.error("Exception in PhaseListener " + phaseId.toString() + " afterPhase", e);

                 }

             }

         }

     }

 }