/*

  * 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.Collection;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import javax.faces.application.ProjectStage;

 import javax.faces.component.UIComponent;

 import javax.faces.context.FacesContext;

 import javax.faces.view.Location;

 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.AbstractFaceletContext;

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

 import org.apache.myfaces.view.facelets.tag.TagHandlerUtils;

 /**

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

  * @version $Revision$ $Date$

  */

 @JSFFaceletTag(name="composite:interface")

 public class InterfaceHandler extends TagHandler implements InterfaceDescriptorCreator

 {

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

     public final static String NAME = "interface";

     /**

      * String array defining all standard attributes of this tag.

      * ATTENTION: this array MUST be sorted alphabetically in order to use binary search!!

      */

     private static final String[] STANDARD_ATTRIBUTES_SORTED = new String[]

     {

         "componentType",

         "displayName",

         "expert",

         "hidden",

         "name",

         "preferred",

         "shortDescription"

     };

     /**

      * 

      */

     @JSFFaceletAttribute(name="name",

             className="javax.el.ValueExpression",

             deferredValueType="java.lang.String")

     private final TagAttribute _name;

     /**

      * 

      */

     @JSFFaceletAttribute(name="componentType",

             className="javax.el.ValueExpression",

             deferredValueType="java.lang.String")

     private final TagAttribute _componentType;

     /**

      * Only available if ProjectStage is Development.

      */

     @JSFFaceletAttribute(name="displayName",

             className="javax.el.ValueExpression",

             deferredValueType="java.lang.String")

     private final TagAttribute _displayName;

     /**

      * Only available if ProjectStage is Development.

      */

     @JSFFaceletAttribute(name="preferred",

             className="javax.el.ValueExpression",

             deferredValueType="boolean")

     private final TagAttribute _preferred;

     /**

      * Only available if ProjectStage is Development.

      */

     @JSFFaceletAttribute(name="expert",

             className="javax.el.ValueExpression",

             deferredValueType="boolean")

     private final TagAttribute _expert;

     /**

      * Only available if ProjectStage is Development.

      */

     @JSFFaceletAttribute(name="shortDescription",

             className="javax.el.ValueExpression",

             deferredValueType="java.lang.String")

     private final TagAttribute _shortDescription;

     /**

      * The "hidden" flag is used to identify features that are intended only 

      * for tool use, and which should not be exposed to humans.

      * Only available if ProjectStage is Development.

      */

     @JSFFaceletAttribute(name="hidden",

             className="javax.el.ValueExpression",

             deferredValueType="boolean")

     protected final TagAttribute _hidden;

     /**

      * Check if the BeanInfo instance created by this handler

      * can be cacheable or not. 

      */

     private boolean _cacheable;

     private Collection<InterfaceDescriptorCreator> attrHandlerList;

     public InterfaceHandler(TagConfig config)

     {

         super(config);

         _name = getAttribute("name");

         _componentType = getAttribute("componentType");

         _displayName = getAttribute("displayName");

         _preferred = getAttribute("preferred");

         _expert = getAttribute("expert");

         _shortDescription = getAttribute("shortDescription");

         _hidden = getAttribute("hidden");

         // Note that only if ProjectStage is Development, The "displayName",

         // "shortDescription", "expert", "hidden", and "preferred" attributes are exposed

         final boolean development = FacesContext.getCurrentInstance()

                 .isProjectStage(ProjectStage.Development);

         // note that we don't have to check the componentType and any unspecified

         // attributes here, because these ones are stored as a ValueExpression in the

         // BeanDescriptor and thus they have no effect on caching

         if ((_name == null || _name.isLiteral()) 

                 && (!development || _areDevelopmentAttributesLiteral()))

         {

             _cacheable = true;

             // Check if all InterfaceDescriptorCreator children are cacheable.

             // If so, we can cache this instance, otherwise not.

             attrHandlerList = 

                 TagHandlerUtils.findNextByType( nextHandler, InterfaceDescriptorCreator.class);

             for (InterfaceDescriptorCreator handler : attrHandlerList)

             {

                 if (!handler.isCacheable())

                 {

                     _cacheable = false;

                     break;

                 }

             }

             if (!_cacheable)

             {

                 // Disable cache on attributes because this tag is the responsible for reuse

                 for (InterfaceDescriptorCreator handler : attrHandlerList)

                 {

                     handler.setCacheable(false);

                 }

             }

         }

         else

         {

             _cacheable = false;

         }

     }

     /**

      * True if the "displayName", "shortDescription", "expert", "hidden", and

      * "preferred" attributes are either null or literal.

      * @return

      */

     private boolean _areDevelopmentAttributesLiteral()

     {

         return CompositeTagAttributeUtils.areAttributesLiteral(

                 _displayName, _shortDescription, _expert, _hidden, _preferred);

     }

     public void apply(FaceletContext ctx, UIComponent parent)

             throws IOException

     {

         // Only apply if we are building composite component metadata,

         // in other words we are calling ViewDeclarationLanguage.getComponentMetadata

         if ( ((AbstractFaceletContext)ctx).isBuildingCompositeComponentMetadata() )

         {

             FaceletCompositionContext fcc = FaceletCompositionContext.getCurrentInstance(ctx);

             UIComponent compositeBaseParent

                     = fcc.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 descriptor = beanInfo.getBeanDescriptor();

             // Add values to descriptor according to pld javadoc

             if (_name != null)

             {

                 descriptor.setName(_name.getValue(ctx));

             }

             if (_componentType != null)

             {

                 // componentType is required by Application.createComponent(FacesContext, Resource)

                 // to instantiate the base component for this composite component. It should be

                 // as family javax.faces.NamingContainer .

                 descriptor.setValue(UIComponent.COMPOSITE_COMPONENT_TYPE_KEY, 

                         _componentType.getValueExpression(ctx, String.class));

             }

             // If ProjectStage is Development, The "displayName", "shortDescription",

             // "expert", "hidden", and "preferred" attributes are exposed

             if (ctx.getFacesContext().isProjectStage(ProjectStage.Development))

             {

                 CompositeTagAttributeUtils.addDevelopmentAttributes(descriptor, ctx, 

                         _displayName, _shortDescription, _expert, _hidden, _preferred);

             }

             // Any additional attributes are exposed as attributes accessible

             // from the getValue() and attributeNames() methods on BeanDescriptor

             CompositeTagAttributeUtils.addUnspecifiedAttributes(descriptor, tag, 

                     STANDARD_ATTRIBUTES_SORTED, ctx);

             try

             {

                 fcc.startComponentUniqueIdSection("__ccmd_");

                 nextHandler.apply(ctx, parent);

             }

             finally

             {

                 fcc.endComponentUniqueIdSection("__ccmd_");

             }

         }

     }

     public boolean isCacheable()

     {

         return _cacheable;

     }

     public void setCacheable(boolean cacheable)

     {

         _cacheable = cacheable;

         for (InterfaceDescriptorCreator handler : attrHandlerList)

         {

             handler.setCacheable(cacheable);

         }

     }

     public Location getLocation()

     {

         return this.tag.getLocation();

     }

 }