package org.apache.maven.project.harness;
   
   /*
    * 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.
   */
  
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.commons.jxpath.ri.Compiler;
  import org.apache.commons.jxpath.ri.compiler.NodeNameTest;
  import org.apache.commons.jxpath.ri.compiler.NodeTest;
  import org.apache.commons.jxpath.ri.compiler.NodeTypeTest;
  import org.apache.commons.jxpath.ri.model.NodeIterator;
  import org.apache.commons.jxpath.ri.model.NodePointer;
  import org.codehaus.plexus.util.StringUtils;
  import org.codehaus.plexus.util.xml.Xpp3Dom;
  
  /**
   * A node iterator for JXPath to support <code>Xpp3Dom</code>.
   * 
   * @author Benjamin Bentmann
   */
  class Xpp3DomNodeIterator
      implements NodeIterator
  {
  
      private NodePointer parent;
  
      private NodeTest test;
  
      private Xpp3Dom node;
  
      private Xpp3Dom[] children;
  
      private List<Xpp3Dom> filteredChildren = new ArrayList<Xpp3Dom>();
  
      private int filteredIndex;
  
      private Xpp3Dom child;
  
      private int position;
  
      public Xpp3DomNodeIterator( NodePointer parent, NodeTest test, boolean reverse, NodePointer startWith )
      {
          this.parent = parent;
          this.node = (Xpp3Dom) parent.getNode();
          this.children = this.node.getChildren();
          if ( startWith != null )
          {
              for ( ; filteredIndex < children.length; filteredIndex++ )
              {
                  if ( startWith.equals( children[filteredIndex] ) )
                  {
                      filteredIndex++;
                      break;
                  }
              }
          }
          this.test = test;
          if ( reverse )
          {
              throw new UnsupportedOperationException();
          }
      }
  
      public NodePointer getNodePointer()
      {
          if ( position == 0 )
          {
              setPosition( 1 );
          }
          return ( child == null ) ? null : new Xpp3DomNodePointer( parent, child );
      }
  
      public int getPosition()
      {
          return position;
      }
  
      public boolean setPosition( int position )
      {
          this.position = position;
          filterChildren( position );
         child = ( position > 0 && position <= filteredChildren.size() ) ? filteredChildren.get( position - 1 ) : null;
         return child != null;
     }
 
     private void filterChildren( int position )
     {
         for ( ; position > filteredChildren.size() && filteredIndex < children.length; filteredIndex++ )
         {
             Xpp3Dom child = children[filteredIndex];
             if ( testNode( child ) )
             {
                 filteredChildren.add( child );
             }
         }
     }
 
     private boolean testNode( Xpp3Dom node )
     {
         if ( test == null )
         {
             return true;
         }
         if ( test instanceof NodeNameTest )
         {
             String nodeName = node.getName();
             if ( StringUtils.isEmpty( nodeName ) )
             {
                 return false;
             }
 
             NodeNameTest nodeNameTest = (NodeNameTest) test;
             String namespaceURI = nodeNameTest.getNamespaceURI();
             boolean wildcard = nodeNameTest.isWildcard();
             String testName = nodeNameTest.getNodeName().getName();
             String testPrefix = nodeNameTest.getNodeName().getPrefix();
             if ( wildcard && testPrefix == null )
             {
                 return true;
             }
             if ( wildcard || testName.equals( nodeName ) )
             {
                 return StringUtils.isEmpty( namespaceURI ) || StringUtils.isEmpty( testPrefix );
             }
             return false;
         }
         if ( test instanceof NodeTypeTest )
         {
             switch ( ( (NodeTypeTest) test ).getNodeType() )
             {
                 case Compiler.NODE_TYPE_NODE:
                     return true;
                 case Compiler.NODE_TYPE_TEXT:
                     return node.getValue() != null;
                 default:
                     return false;
             }
         }
         return false;
     }
 
 }