/*   Copyright 2004 The Apache Software Foundation
 *
 *   Licensed 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 dom.common;

import org.w3c.dom.Attr;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;


public  class DomUtils{


     /**
     * @return true if sets are the same
     */
    public static boolean compareNamedNodeMaps(NamedNodeMap atrSet1,NamedNodeMap atrSet2){
	if (atrSet1==null)
	    if (atrSet2==null) return true;
	    else return false;
	else if (atrSet2==null) return false;

	int nLen1=atrSet1.getLength();
	Attr at1,
	    at2;

	if (nLen1!=atrSet2.getLength())
	    return false;
	for (int i=0;i<nLen1;i++){
	    at1=(Attr)atrSet1.item(i);
	    at2=(Attr)atrSet2.getNamedItem(at1.getName());
	    if (at2==null) return false;
	    else if (!
		     (at1.getNodeName().equals(at2.getNodeName())) &&
		     (at1.getNamespaceURI().equals(at2.getNamespaceURI())) &&
		     (at1.getValue().equals(at2.getValue()))
		     )
		return false;
	    else if (at1==at2) return false;
	}
	return true;
    }
    /**
     * node is a copy
     * children are the same obj
     */
    public static boolean compareNodesShallow(Node n1,Node n2){
	return (
		n1.getNodeName().equals(n2.getNodeName()) &&
		n1.getNamespaceURI().equals(n2.getNamespaceURI()) &&
		n1.getPrefix().equals( n2.getPrefix()) &&
		compareNamedNodeMaps(n1.getAttributes(),n2.getAttributes())
		// cloned nodes never have children
                //  && compareNodeTreePtr(n1.getChildNodes(),n2.getChildNodes())
		 );
    }
    //equates "" to null
                         private static boolean compareNull(String pre1, String pre2){
                             if (pre1==null && pre2==null)return true;
                             if (pre1==null && pre2.equals(""))return true;
                             if (pre1.equals("") && pre2==null)return true;
                             else return pre1.equals(pre2) ;


                         }
    /**
     * node is a copy
     * children copies
     */
    public static boolean compareNodesDeep(Node n1,Node n2) throws IllegalStateException{
	if( n1==n2 && n1==null) return true;
    if (n1==null && n2!=null || n2==null && n1!=null)return false;
	if (! (n1.getNodeName().equals(n2.getNodeName()) &&
		compareNull(n1.getNamespaceURI(),n2.getNamespaceURI()) &&
		compareNull(n1.getPrefix(), n2.getPrefix()) )
	    )
	    throw new IllegalStateException("Diff QNames "+n1.getNamespaceURI()+" * "+n1.getPrefix()+":"+n1.getNodeName()+
					   "AND "+n2.getNamespaceURI()+" * "+n2.getPrefix()+":"+n2.getNodeName());
	else if ( !compareNamedNodeMaps(n1.getAttributes(),n2.getAttributes()) )
	    throw new IllegalStateException("Diff Attrs "+n1.getAttributes().getLength()+
					   "AND "+n2.getAttributes().getLength());

	else if  (n1.hasChildNodes()     //Xerces attr quirk
                && n2.hasChildNodes() ){
                if (! compareNodeTreeValue(n1.getChildNodes(),n2.getChildNodes()) )
	                throw new IllegalStateException("Diff Children "+n1.getNodeName()+
					   "AND "+n2.getNodeName());
        }
   else  if (n1.hasChildNodes()     //Xerces attr quirk
                ^ n2.hasChildNodes() )
        throw new IllegalStateException("One node has Children, other one not ");


	return true;
    }

    /** the two node lists really are the same list*/
    public static boolean compareNodeTreePtr(NodeList lst1,NodeList lst2){
	if (lst1.getLength()!=lst2.getLength())
	    return false;

	for (int i=0;i<lst1.getLength();i++){
	    if (lst1.item(i)!=lst2.item(i))
		return false;
	}
	return true;
    }

    public static boolean compareNodeTreeValue(NodeList lst1,NodeList lst2){
	if (lst1.getLength()!=lst2.getLength())
	    return false;
	boolean result=true;
	for (int i=0;i<lst1.getLength();i++){
	    result=result&&compareNodesDeep(lst1.item(i),
					    lst2.item(i));

	    }
	return result;
	}

}