/*

  * 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.view.facelets.tag.composite;

 import java.beans.BeanDescriptor;

 import java.io.IOException;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import javax.faces.component.UIComponent;

 import javax.faces.view.AttachedObjectTarget;

 import javax.faces.view.facelets.FaceletContext;

 import javax.faces.view.facelets.TagAttribute;

 import javax.faces.view.facelets.TagConfig;

 import javax.faces.view.facelets.TagHandler;

 import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFFaceletAttribute;

 import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFFaceletTag;

 import org.apache.myfaces.view.facelets.FaceletCompositionContext;

 /**

  * composite:actionSource, composite:valueHolder and composite:editableValueHolder

  * do the same: register an AttachedObjectTarget on the "targetList" mentioned on

  * ViewDeclarationLanguage.retargetAttachedObjects. AttachedObjectTargetHandler group the

  * common behavior

  * 

  * @author Leonardo Uribe (latest modification by $Author$)

  * @version $Revision$ $Date$

  */

 @JSFFaceletTag

 public abstract class AttachedObjectTargetHandler<T extends AttachedObjectTarget> 

     extends TagHandler implements InterfaceDescriptorCreator

 {

     //private static final Log log = LogFactory.getLog(AttachedObjectTargetHandler.class);

     private static final Logger log = Logger.getLogger(AttachedObjectTargetHandler.class.getName());

     /**

      * Indicate the name of the attribute that the component should expose

      * to page authors.

      * 

      */

     @JSFFaceletAttribute(name="name",

             className="javax.el.ValueExpression",

             deferredValueType="java.lang.String",

             required=true)

     protected final TagAttribute _name;

     /**

      * 

      */

     @JSFFaceletAttribute(name="targets",

             className="javax.el.ValueExpression",

             deferredValueType="java.lang.String")

     protected final TagAttribute _targets;

     /**

      * Check if the PropertyDescriptor instance created by this handler

      * can be cacheable or not. 

      */

     private boolean _cacheable;

     private AttachedObjectTarget _target;

     public AttachedObjectTargetHandler(TagConfig config)

     {

         super(config);

         _name = getRequiredAttribute("name");

         _targets = getAttribute("targets");

         if (_name.isLiteral())

         {

             _cacheable = true;

         }

         else

         {

             _cacheable = false;

         }

     }

     @SuppressWarnings("unchecked")

     public void apply(FaceletContext ctx, UIComponent parent)

             throws IOException

     {

         UIComponent compositeBaseParent

                 = FaceletCompositionContext.getCurrentInstance(ctx).getCompositeComponentFromStack();

         CompositeComponentBeanInfo beanInfo = 

             (CompositeComponentBeanInfo) compositeBaseParent.getAttributes()

             .get(UIComponent.BEANINFO_KEY);

         if (beanInfo == null)

         {

             if (log.isLoggable(Level.SEVERE))

             {

                 log.severe("Cannot find composite bean descriptor UIComponent.BEANINFO_KEY ");

             }

             return;

         }

         BeanDescriptor beanDescriptor = beanInfo.getBeanDescriptor(); 

         //1. Obtain the list mentioned as "targetList" on ViewDeclarationLanguage.retargetAttachedObjects

         List<AttachedObjectTarget> targetList = (List<AttachedObjectTarget>)

             beanDescriptor.getValue(

                     AttachedObjectTarget.ATTACHED_OBJECT_TARGETS_KEY);

         if (targetList == null)

         {

             //2. If not found create it and set

             targetList = new ArrayList<AttachedObjectTarget>();

             beanDescriptor.setValue(

                     AttachedObjectTarget.ATTACHED_OBJECT_TARGETS_KEY,

                     targetList);

         }

         //3. Create the instance of AttachedObjectTarget

         if (isCacheable())

         {

             if (_target == null)

             {

                 _target = createAttachedObjectTarget(ctx);

             }

             targetList.add(_target);

         }

         else

         {

             AttachedObjectTarget target = createAttachedObjectTarget(ctx);

             targetList.add(target);

         }

         this.nextHandler.apply(ctx, parent);

     }

     public boolean isCacheable()

     {

         return _cacheable;

     }

     public void setCacheable(boolean cacheable)

     {

         _cacheable = cacheable;

     }

     //@Override

     //public FaceletHandler getNextHandler()

     //{

     //    return nextHandler;

     //}

     /**

      * Create a new AttachedObjectTarget instance to be added on the 

      * target list.

      * 

      * @return

      */

     protected abstract T createAttachedObjectTarget(FaceletContext ctx);    

 }