/*
    * 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 javax.faces.webapp;
  
  import javax.faces.component.UIComponent;
  import javax.faces.context.FacesContext;
  import javax.faces.el.ValueBinding;
  import javax.servlet.jsp.JspException;
  import javax.servlet.jsp.tagext.Tag;
  import javax.servlet.jsp.tagext.TagSupport;
  
  /**
   * see Javadoc of <a href="http://java.sun.com/javaee/javaserverfaces/1.2/docs/api/index.html">JSF Specification</a>
   * 
   * @deprecated the implementation of this clazz is now an implementation detail.
   */
  public class AttributeTag extends TagSupport
  {
      private static final long serialVersionUID = 3147657100171678632L;
      private String _name;
      private String _value;
  
      /**
       * @deprecated
       * @param name
       */
      public void setName(String name)
      {
          _name = name;
      }
  
      /**
       * @deprecated
       * @param value
       */
      public void setValue(String value)
      {
          _value = value;
      }
  
      /**
       * @deprecated
       */
      @Override
      public int doStartTag() throws JspException
      {
          UIComponentTag componentTag = UIComponentTag.getParentUIComponentTag(pageContext);
          if (componentTag == null)
          {
              throw new JspException("no parent UIComponentTag found");
          }
          UIComponent component = componentTag.getComponentInstance();
          if (component == null)
          {
              throw new JspException("parent UIComponentTag has no UIComponent");
          }
          String name = getName();
          if (component.getAttributes().get(name) == null)
          {
              Object value = getValue();
  
              if (value != null)
              {
                  component.getAttributes().put(name, value);
              }
          }
          return Tag.SKIP_BODY;
      }
  
      /**
       * @deprecated
       */
      @Override
      public void release()
      {
          super.release();
          _name = null;
          _value = null;
      }
  
      private String getName()
      {
          if (UIComponentTag.isValueReference(_name))
         {
             FacesContext facesContext = FacesContext.getCurrentInstance();
             ValueBinding vb = facesContext.getApplication().createValueBinding(_name);
             return (String)vb.getValue(facesContext);
         }
 
         return _name;
     }
 
     private Object getValue()
     {
         if (UIComponentTag.isValueReference(_value))
         {
             FacesContext facesContext = FacesContext.getCurrentInstance();
             ValueBinding vb = facesContext.getApplication().createValueBinding(_value);
             return vb.getValue(facesContext);
         }
 
         return _value;
     }
 
 }