package org.jaxen.jdom;

 /*

  * $Header$

  * $Revision: 1198 $

  * $Date: 2006-09-21 04:48:05 -0700 (Thu, 21 Sep 2006) $

  *

  * ====================================================================

  *

  * Copyright 2000-2005 bob mcwhirter & James Strachan.

  * All rights reserved.

  *

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions are

  * met:

  * 

  *   * Redistributions of source code must retain the above copyright

  *     notice, this list of conditions and the following disclaimer.

  * 

  *   * Redistributions in binary form must reproduce the above copyright

  *     notice, this list of conditions and the following disclaimer in the

  *     documentation and/or other materials provided with the distribution.

  * 

  *   * Neither the name of the Jaxen Project nor the names of its

  *     contributors may be used to endorse or promote products derived 

  *     from this software without specific prior written permission.

  * 

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED

  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A

  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER

  * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

  *

  * ====================================================================

  * This software consists of voluntary contributions made by many

  * individuals on behalf of the Jaxen Project and was originally

  * created by bob mcwhirter <bob@werken.com> and

  * James Strachan <jstrachan@apache.org>.  For more information on the

  * Jaxen Project, please see <http://www.jaxen.org/>.

  *

  * $Id: DocumentNavigator.java 1198 2006-09-21 11:48:05Z elharo $

 */

 import java.util.HashMap;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Map;

 import org.jaxen.DefaultNavigator;

 import org.jaxen.FunctionCallException;

 import org.jaxen.NamedAccessNavigator;

 import org.jaxen.Navigator;

 import org.jaxen.XPath;

 import org.jaxen.JaxenConstants;

 import org.jaxen.saxpath.SAXPathException;

 import org.jaxen.util.SingleObjectIterator;

 import org.jdom.Attribute;

 import org.jdom.CDATA;

 import org.jdom.Comment;

 import org.jdom.Document;

 import org.jdom.Element;

 import org.jdom.Namespace;

 import org.jdom.ProcessingInstruction;

 import org.jdom.Text;

 import org.jdom.input.SAXBuilder;

 /** 

  * Interface for navigating around the JDOM object model.

  *

  * <p>

  * This class is not intended for direct usage, but is

  * used by the Jaxen engine during evaluation.

  * </p>

  *

  * @see XPath

  *

  * @author <a href="mailto:bob@werken.com">bob mcwhirter</a>

  * @author Stephen Colebourne

  */

 public class DocumentNavigator extends DefaultNavigator implements NamedAccessNavigator

 {

     /**

      * 

      */

     private static final long serialVersionUID = -1636727587303584165L;

     /** Singleton implementation.

      */

     private static class Singleton

     {

         /** Singleton instance.

          */

         private static DocumentNavigator instance = new DocumentNavigator();

     }

     public static Navigator getInstance()

     {

         return Singleton.instance;

     }

     public boolean isElement(Object obj)

     {

         return obj instanceof Element;

     }

     public boolean isComment(Object obj)

     {

         return obj instanceof Comment;

     }

     public boolean isText(Object obj)

     {

         return ( obj instanceof Text

                  ||

                  obj instanceof CDATA );

     }

     public boolean isAttribute(Object obj)

     {

         return obj instanceof Attribute;

     }

     public boolean isProcessingInstruction(Object obj)

     {

         return obj instanceof ProcessingInstruction;

     }

     public boolean isDocument(Object obj)

     {

         return obj instanceof Document;

     }

     public boolean isNamespace(Object obj)

     {

         return obj instanceof Namespace || obj instanceof XPathNamespace;

     }

     public String getElementName(Object obj)

     {

         Element elem = (Element) obj;

         return elem.getName();

     }

     public String getElementNamespaceUri(Object obj)

     {

         Element elem = (Element) obj;

         String uri = elem.getNamespaceURI();

         if ( uri != null && uri.length() == 0 ) 

             return null;

         else

             return uri;

     }

     public String getAttributeName(Object obj)

     {

         Attribute attr = (Attribute) obj;

         return attr.getName();

     }

     public String getAttributeNamespaceUri(Object obj)

     {

         Attribute attr = (Attribute) obj;

         String uri = attr.getNamespaceURI();

         if ( uri != null && uri.length() == 0 ) 

             return null;

         else

             return uri;

     }

     public Iterator getChildAxisIterator(Object contextNode)

     {

         if ( contextNode instanceof Element )

         {

             return ((Element)contextNode).getContent().iterator();

         }

         else if ( contextNode instanceof Document )

         {

             return ((Document)contextNode).getContent().iterator();

         }

         return JaxenConstants.EMPTY_ITERATOR;

     }

     /**

      * Retrieves an <code>Iterator</code> over the child elements that

      * match the supplied local name and namespace URI.

      *

      * @param contextNode      the origin context node

      * @param localName        the local name of the children to return, always present

      * @param namespacePrefix  ignored; prefixes are not used when matching in XPath

      * @param namespaceURI     the URI of the namespace of the children to return

      * @return an Iterator     that traverses the named children, or null if none

      */

     public Iterator getChildAxisIterator(

             Object contextNode, String localName, String namespacePrefix, String namespaceURI) {

         if ( contextNode instanceof Element ) {

             Element node = (Element) contextNode;

             if (namespaceURI == null) {

                 return node.getChildren(localName).iterator();

             }

             return node.getChildren(localName, Namespace.getNamespace(namespacePrefix, namespaceURI)).iterator();

         }

         if ( contextNode instanceof Document ) {

             Document node = (Document) contextNode;

             Element el = node.getRootElement();

             if (el.getName().equals(localName) == false) {

                 return JaxenConstants.EMPTY_ITERATOR;

             }

             if (namespaceURI != null) {

                 // JDOM's equals method does not consider the prefix when comparing namespace objects

                 if (!Namespace.getNamespace(namespacePrefix, namespaceURI).equals(el.getNamespace())) {

                     return JaxenConstants.EMPTY_ITERATOR;

                 }

             }

             else if(el.getNamespace() != Namespace.NO_NAMESPACE) { 

                 return JaxenConstants.EMPTY_ITERATOR; 

             }

             return new SingleObjectIterator(el);

         }

         return JaxenConstants.EMPTY_ITERATOR;

     }

     public Iterator getNamespaceAxisIterator(Object contextNode)

     {

         if ( ! ( contextNode instanceof Element ) )

         {

             return JaxenConstants.EMPTY_ITERATOR;

         }

         Element elem = (Element) contextNode;

         Map nsMap = new HashMap();

         Element current = elem;

         while ( current != null ) {

             Namespace ns = current.getNamespace();

             if ( ns != Namespace.NO_NAMESPACE ) {

                 if ( !nsMap.containsKey(ns.getPrefix()) )

                     nsMap.put( ns.getPrefix(), new XPathNamespace(elem, ns) );

             }

             Iterator additional = current.getAdditionalNamespaces().iterator();

             while ( additional.hasNext() ) {

                 ns = (Namespace)additional.next();

                 if ( !nsMap.containsKey(ns.getPrefix()) )

                     nsMap.put( ns.getPrefix(), new XPathNamespace(elem, ns) );

             }

             Iterator attributes = current.getAttributes().iterator();

             while ( attributes.hasNext() ) {

                 Attribute attribute = (Attribute)attributes.next();

                 Namespace attrNS = attribute.getNamespace();

                 if ( attrNS != Namespace.NO_NAMESPACE ) {

                     if ( !nsMap.containsKey(attrNS.getPrefix()) )

                         nsMap.put( attrNS.getPrefix(), new XPathNamespace(elem, attrNS) );

                 }

             }

             if (current.getParent() instanceof Element) {

                 current = (Element)current.getParent();

             } else {

                 current = null;

             }

         }

         nsMap.put( "xml", new XPathNamespace(elem, Namespace.XML_NAMESPACE) );

         return nsMap.values().iterator();

     }

     public Iterator getParentAxisIterator(Object contextNode)

     {

         Object parent = null;

         if ( contextNode instanceof Document )

         {

             return JaxenConstants.EMPTY_ITERATOR;

         }

         else if ( contextNode instanceof Element )

         {

             parent = ((Element)contextNode).getParent();

             if ( parent == null )

             {

                 if ( ((Element)contextNode).isRootElement() )

                 {

                     parent = ((Element)contextNode).getDocument();

                 }

             }

         }

         else if ( contextNode instanceof Attribute )

         {

             parent = ((Attribute)contextNode).getParent();

         }

         else if ( contextNode instanceof XPathNamespace )

         {

             parent = ((XPathNamespace)contextNode).getJDOMElement();

         }

         else if ( contextNode instanceof ProcessingInstruction )

         {

             parent = ((ProcessingInstruction)contextNode).getParent();

         }

         else if ( contextNode instanceof Comment )

         {

             parent = ((Comment)contextNode).getParent();

         }

         else if ( contextNode instanceof Text )

         {

             parent = ((Text)contextNode).getParent();

         }

         if ( parent != null )

         {

             return new SingleObjectIterator( parent );

         }

         return JaxenConstants.EMPTY_ITERATOR;

     }

     public Iterator getAttributeAxisIterator(Object contextNode)

     {

         if ( ! ( contextNode instanceof Element ) )

         {

             return JaxenConstants.EMPTY_ITERATOR;

         }

         Element elem = (Element) contextNode;

         return elem.getAttributes().iterator();

     }

     /**

      * Retrieves an <code>Iterator</code> over the attribute elements that

      * match the supplied name.

      *

      * @param contextNode      the origin context node

      * @param localName        the local name of the attributes to return, always present

      * @param namespacePrefix  the prefix of the namespace of the attributes to return

      * @param namespaceURI     the URI of the namespace of the attributes to return

      * @return an Iterator     that traverses the named attributes, not null

      */

     public Iterator getAttributeAxisIterator(

             Object contextNode, String localName, String namespacePrefix, String namespaceURI) {

         if ( contextNode instanceof Element ) {

             Element node = (Element) contextNode;

             Namespace namespace = (namespaceURI == null ? Namespace.NO_NAMESPACE : 

                                     Namespace.getNamespace(namespacePrefix, namespaceURI));

             Attribute attr = node.getAttribute(localName, namespace);

             if (attr != null) {

                 return new SingleObjectIterator(attr);

             }

         }

         return JaxenConstants.EMPTY_ITERATOR;

     }

     /** Returns a parsed form of the given XPath string, which will be suitable

      *  for queries on JDOM documents.

      */

     public XPath parseXPath (String xpath) throws SAXPathException

     {

         return new JDOMXPath(xpath);

     }

     public Object getDocumentNode(Object contextNode)

     {

         if ( contextNode instanceof Document )

         {

             return contextNode;

         }

         Element elem = (Element) contextNode;

         return elem.getDocument();

     }

     public String getElementQName(Object obj)

     {

         Element elem = (Element) obj;

         String prefix = elem.getNamespacePrefix();

         if ( prefix == null || prefix.length() == 0 )

         {

             return elem.getName();

         }

         return prefix + ":" + elem.getName();

     }

     public String getAttributeQName(Object obj)

     {

         Attribute attr = (Attribute) obj;

         String prefix = attr.getNamespacePrefix();

         if ( prefix == null || "".equals( prefix ) )

         {

             return attr.getName();

         }

         return prefix + ":" + attr.getName();

     }

     public String getNamespaceStringValue(Object obj)

     {

         if (obj instanceof Namespace) {

             Namespace ns = (Namespace) obj;

             return ns.getURI();

         } else {

             XPathNamespace ns = (XPathNamespace) obj;

             return ns.getJDOMNamespace().getURI();

         }

     }

     public String getNamespacePrefix(Object obj)

     {

         if (obj instanceof Namespace) {

             Namespace ns = (Namespace) obj;

             return ns.getPrefix();

         } else {

             XPathNamespace ns = (XPathNamespace) obj;

             return ns.getJDOMNamespace().getPrefix();

         }

     }

     public String getTextStringValue(Object obj)

     {

         if ( obj instanceof Text )

         {

             return ((Text)obj).getText();

         }

         if ( obj instanceof CDATA )

         {

             return ((CDATA)obj).getText();

         }

         return "";

     }

     public String getAttributeStringValue(Object obj)

     {

         Attribute attr = (Attribute) obj;

         return attr.getValue();

     }

     public String getElementStringValue(Object obj)

     {

         Element elem = (Element) obj;

         StringBuffer buf = new StringBuffer();

         List     content     = elem.getContent();

         Iterator contentIter = content.iterator();

         Object   each        = null;

         while ( contentIter.hasNext() )

         {

             each = contentIter.next();

             if ( each instanceof Text )

             {

                 buf.append( ((Text)each).getText() );

             }

             else if ( each instanceof CDATA )

             {

                 buf.append( ((CDATA)each).getText() );

             }

             else if ( each instanceof Element )

             {

                 buf.append( getElementStringValue( each ) );

             }

         }

         return buf.toString();

     }

     public String getProcessingInstructionTarget(Object obj)

     {

         ProcessingInstruction pi = (ProcessingInstruction) obj;

         return pi.getTarget();

     }

     public String getProcessingInstructionData(Object obj)

     {

         ProcessingInstruction pi = (ProcessingInstruction) obj;

         return pi.getData();

     }

     public String getCommentStringValue(Object obj)

     {

         Comment cmt = (Comment) obj;

         return cmt.getText();

     }

     public String translateNamespacePrefixToUri(String prefix, Object context)

     {

         Element element = null;

         if ( context instanceof Element ) 

         {

             element = (Element) context;

         }

         else if ( context instanceof Text )

         {

             element = (Element)((Text)context).getParent();

         }

         else if ( context instanceof Attribute )

         {

             element = ((Attribute)context).getParent();

         }

         else if ( context instanceof XPathNamespace )

         {

             element = ((XPathNamespace)context).getJDOMElement();

         }

         else if ( context instanceof Comment )

         {

             element = (Element)((Comment)context).getParent();

         }

         else if ( context instanceof ProcessingInstruction )

         {

             element = (Element)((ProcessingInstruction)context).getParent();

         }

         if ( element != null )

         {

             Namespace namespace = element.getNamespace( prefix );

             if ( namespace != null ) 

             {

                 return namespace.getURI();

             }

         }

         return null;

     }

     public Object getDocument(String url) throws FunctionCallException

     {

         try

         {

             SAXBuilder builder = new SAXBuilder();

             return builder.build( url );

         }

         catch (Exception e)

         {

             throw new FunctionCallException( e.getMessage() );

         }

     }

 }