/*
    * 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.commons.jxpath.ri.model.dom;
  
  import org.apache.commons.jxpath.ri.Compiler;
  import org.apache.commons.jxpath.ri.QName;
  import org.apache.commons.jxpath.ri.compiler.NodeTest;
  import org.apache.commons.jxpath.ri.compiler.NodeTypeTest;
  import org.apache.commons.jxpath.ri.model.NodePointer;
  import org.apache.commons.jxpath.util.TypeUtils;
  import org.w3c.dom.Attr;
  
  /**
   * A Pointer that points to a DOM node. Because the underlying DOM Attr is not Serializable,
   * neither is this pointer class truly so.
   *
   * @author Dmitri Plotnikov
   * @version $Revision: 670727 $ $Date: 2008-06-23 22:10:38 +0200 (Mo, 23 Jun 2008) $
   */
  public class DOMAttributePointer extends NodePointer {
      private static final long serialVersionUID = 1115085175427555951L;
  
      private Attr attr;
  
      /**
       * Create a new DOMAttributePointer.
       * @param parent pointer
       * @param attr pointed
       */
      public DOMAttributePointer(NodePointer parent, Attr attr) {
          super(parent);
          this.attr = attr;
      }
  
      public QName getName() {
          return new QName(
              DOMNodePointer.getPrefix(attr),
              DOMNodePointer.getLocalName(attr));
      }
  
      public String getNamespaceURI() {
          String prefix = DOMNodePointer.getPrefix(attr);
          return prefix == null ? null : parent.getNamespaceURI(prefix);
      }
  
      public Object getValue() {
          String value = attr.getValue();
          if (value == null || (value.equals("") && !attr.getSpecified())) {
              return null;
          }
          return value;
      }
  
      public Object getBaseValue() {
          return attr;
      }
  
      public boolean isCollection() {
          return false;
      }
  
      public int getLength() {
          return 1;
      }
  
      public Object getImmediateNode() {
          return attr;
      }
  
      public boolean isActual() {
          return true;
      }
  
      public boolean isLeaf() {
          return true;
      }
  
      public boolean testNode(NodeTest nodeTest) {
          return nodeTest == null
              || ((nodeTest instanceof NodeTypeTest)
                  && ((NodeTypeTest) nodeTest).getNodeType() == Compiler.NODE_TYPE_NODE);
      }
  
      /**
       * Sets the value of this attribute.
      * @param value to set
      */
     public void setValue(Object value) {
         attr.setValue((String) TypeUtils.convert(value, String.class));
     }
 
     public void remove() {
         attr.getOwnerElement().removeAttributeNode(attr);
     }
 
     public String asPath() {
         StringBuffer buffer = new StringBuffer();
         if (parent != null) {
             buffer.append(parent.asPath());
             if (buffer.length() == 0
                 || buffer.charAt(buffer.length() - 1) != '/') {
                 buffer.append('/');
             }
         }
         buffer.append('@');
         buffer.append(getName());
         return buffer.toString();
     }
 
     public int hashCode() {
         return System.identityHashCode(attr);
     }
 
     public boolean equals(Object object) {
         return object == this || object instanceof DOMAttributePointer
                 && attr == ((DOMAttributePointer) object).attr;
     }
 
     public int compareChildNodePointers(NodePointer pointer1,
             NodePointer pointer2) {
         // Won't happen - attributes don't have children
         return 0;
     }
 }