/*
    * 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;
  
  /**
   * Represents a namespace node.
   */
  public class NamespacePointer extends NodePointer {
  
      private static final long serialVersionUID = -7622456151550131709L;
  
      /**
       * Namespace prefix.
       */
      private final String prefix;
  
      /**
       * Namespace URI String.
       */
      private String namespaceURI;
  
      /**
       * Constructs a new NamespacePointer.
       *
       * @param parent parent pointer
       * @param prefix namespace prefix.
       */
      public NamespacePointer(final NodePointer parent, final String prefix) {
          super(parent);
          this.prefix = prefix;
      }
  
      /**
       * Constructs a new NamespacePointer.
       *
       * @param parent       parent pointer
       * @param prefix       namespace prefix.
       * @param namespaceURI namespace URI.
       */
      public NamespacePointer(final NodePointer parent, final String prefix, final String namespaceURI) {
          super(parent);
          this.prefix = prefix;
          this.namespaceURI = namespaceURI;
      }
  
      @Override
      public String asPath() {
          final StringBuilder buffer = new StringBuilder();
          if (parent != null) {
              buffer.append(parent.asPath());
              if (buffer.length() == 0 || buffer.charAt(buffer.length() - 1) != '/') {
                  buffer.append('/');
              }
          }
          buffer.append("namespace::");
          buffer.append(prefix);
          return buffer.toString();
      }
  
      @Override
      public int compareChildNodePointers(final NodePointer pointer1, final NodePointer pointer2) {
          // Won't happen - namespaces don't have children
          return 0;
      }
  
      @Override
      public boolean equals(final Object object) {
          if (object == this) {
              return true;
          }
          if (!(object instanceof NamespacePointer)) {
              return false;
          }
          final NamespacePointer other = (NamespacePointer) object;
          return prefix.equals(other.prefix);
      }
  
      @Override
     public Object getBaseValue() {
         return null;
     }
 
     @Override
     public Object getImmediateNode() {
         return getNamespaceURI();
     }
 
     @Override
     public int getLength() {
         return 1;
     }
 
     @Override
     public QName getName() {
         return new QName(prefix);
     }
 
     @Override
     public String getNamespaceURI() {
         if (namespaceURI == null) {
             namespaceURI = parent.getNamespaceURI(prefix);
         }
         return namespaceURI;
     }
 
     @Override
     public int hashCode() {
         return prefix.hashCode();
     }
 
     @Override
     public boolean isCollection() {
         return false;
     }
 
     @Override
     public boolean isLeaf() {
         return true;
     }
 
     /**
      * Throws UnsupportedOperationException.
      *
      * @param value Object
      */
     @Override
     public void setValue(final Object value) {
         throw new UnsupportedOperationException("Cannot modify DOM trees");
     }
 
     @Override
     public boolean testNode(final NodeTest nodeTest) {
         return nodeTest == null || nodeTest instanceof NodeTypeTest && ((NodeTypeTest) nodeTest).getNodeType() == Compiler.NODE_TYPE_NODE;
     }
 }