/*
 * Copyright 2005 the original author or authors.
 * 
 * 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 org.wamblee.xml;

import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import junit.framework.TestCase;

import org.dom4j.Attribute;
import org.dom4j.Document;
import org.dom4j.Element;



/**
 * XML test support utilities. 
 */
public final class XmlUtils {

    /**
     * Disabled constructor. 
     *
     */
    private XmlUtils() { 
        // Empty
    }
    
    /**
     * Checks equality of two XML documents excluding comment and processing nodes and 
     * trimming the text of the elements.  
     * @param aMsg
     * @param aExpected
     * @param aActual
     */
    public static void assertEquals(String aMsg, Document aExpected, Document aActual) { 
        assertEquals(aMsg, aExpected.getRootElement(), aActual.getRootElement());
    }
    
    /**
     * Checks equality of two XML elements excluding comment and processing nodes and trimming 
     * the text of the elements.  
     * @param aMsg
     * @param aExpected
     * @param aActual
     */
    public static void assertEquals(String aMsg, Element aExpected, Element aActual) {
        
        // Name.
        TestCase.assertEquals(aMsg + "/name()", aExpected.getName(), aActual.getName());
        
        // Text
        TestCase.assertEquals(aMsg + "/text()", aExpected.getTextTrim(), aActual.getTextTrim());
      
        // Attributes
        List<Attribute> expectedAttrs = aExpected.attributes(); 
        Collections.sort(expectedAttrs, new AttributeComparator());
        List<Attribute> actualAttrs = aActual.attributes(); 
        Collections.sort(actualAttrs, new AttributeComparator());
        
        TestCase.assertEquals(aMsg + "/#attributes", expectedAttrs.size(), actualAttrs.size());
        for (int i = 0; i < expectedAttrs.size(); i++) { 
            String msg = aMsg + "/attribute(" + i + ")"; 
            assertEquals(msg, expectedAttrs.get(i), actualAttrs.get(i));
        }
        
        // Nested elements. 
        List<Element> expectedElems = aExpected.elements();
        List<Element> actualElems = aActual.elements(); 
        TestCase.assertEquals(aMsg + "/#elements", expectedElems.size(), actualElems.size());
        for (int i = 0; i < expectedElems.size(); i++) { 
            String msg = aMsg + "/element(" + i + ")"; 
            assertEquals(msg, expectedElems.get(i), actualElems.get(i));
        }
    }
    
    /**
     * Checks equality of two attributes.
     * @param aMsg
     * @param aExpected
     * @param aActual
     */
    public static void assertEquals(String aMsg, Attribute aExpected, Attribute aActual) { 
        TestCase.assertEquals(aMsg + "@", aExpected.getName() + ":name", aActual.getName());
        TestCase.assertEquals(aMsg + "@" + aExpected.getName() + ":value", 
                aExpected.getValue(), aActual.getValue());    
    }
    
    /**
     * Comparator which compares attributes by name. 
     */
    private static final class AttributeComparator implements Comparator<Attribute> { 
        /* (non-Javadoc)
         * @see java.util.Comparator#compare(T, T)
         */
        public int compare(Attribute aAttribute1, Attribute aAttribute2) {
            return aAttribute1.getName().compareTo(aAttribute2.getName());
        }
    }
}