/*
    * 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();
     }
 }