/*
    * 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.jsf;
  
  import javax.faces.component.UIComponent;
  import javax.faces.component.ValueHolder;
  import javax.faces.convert.Converter;
  import javax.faces.view.facelets.FaceletContext;
  import javax.faces.view.facelets.MetaRule;
  import javax.faces.view.facelets.Metadata;
  import javax.faces.view.facelets.MetadataTarget;
  import javax.faces.view.facelets.TagAttribute;
  
  /**
   * 
   * @author Jacob Hookom
   * @version $Id$
   */
  public final class ValueHolderRule extends MetaRule
  {
  
      final static class LiteralConverterMetadata extends Metadata
      {
  
          private final String converterId;
  
          public LiteralConverterMetadata(String converterId)
          {
              this.converterId = converterId;
          }
  
          public void applyMetadata(FaceletContext ctx, Object instance)
          {
              ((ValueHolder) instance).setConverter(ctx.getFacesContext().getApplication()
                      .createConverter(this.converterId));
          }
      }
  
      final static class DynamicConverterMetadata2 extends Metadata
      {
  
          private final TagAttribute attr;
  
          public DynamicConverterMetadata2(TagAttribute attr)
          {
              this.attr = attr;
          }
  
          public void applyMetadata(FaceletContext ctx, Object instance)
          {
              ((UIComponent) instance).setValueExpression("converter", attr.getValueExpression(ctx, Converter.class));
          }
      }
  
      final static class LiteralValueMetadata extends Metadata
      {
  
          private final String value;
  
          public LiteralValueMetadata(String value)
          {
              this.value = value;
          }
  
          public void applyMetadata(FaceletContext ctx, Object instance)
          {
              ((ValueHolder) instance).setValue(this.value);
          }
      }
  
      final static class DynamicValueExpressionMetadata extends Metadata
      {
  
          private final TagAttribute attr;
  
          public DynamicValueExpressionMetadata(TagAttribute attr)
          {
              this.attr = attr;
          }
  
          public void applyMetadata(FaceletContext ctx, Object instance)
          {
              ((UIComponent) instance).setValueExpression("value", attr.getValueExpression(ctx, Object.class));
         }
     }
 
     public final static ValueHolderRule INSTANCE = new ValueHolderRule();
 
     public Metadata applyRule(String name, TagAttribute attribute, MetadataTarget meta)
     {
         if (meta.isTargetInstanceOf(ValueHolder.class))
         {
 
             if ("converter".equals(name))
             {
                 if (attribute.isLiteral())
                 {
                     return new LiteralConverterMetadata(attribute.getValue());
                 }
                 else
                 {
                     return new DynamicConverterMetadata2(attribute);
                 }
             }
 
             if ("value".equals(name))
             {
                 if (attribute.isLiteral())
                 {
                     return new LiteralValueMetadata(attribute.getValue());
                 }
                 else
                 {
                     return new DynamicValueExpressionMetadata(attribute);
                 }
             }
         }
         return null;
     }
 
 }