package org.apache.axis2.schema.populate.derived;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.lang.reflect.Method;

import javax.xml.stream.XMLOutputFactory;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamWriter;

import org.apache.axiom.om.OMAbstractFactory;
import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.util.StAXUtils;
import org.custommonkey.xmlunit.XMLTestCase;
/*
 * Copyright 2004,2005 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.
 */

public abstract class AbstractDerivedPopulater extends XMLTestCase {

    // force others to implement this method
    public abstract void testPopulate() throws Exception;

    /**
     * Simple reusable method to make object instances via reflection
     */
    protected Object process(String testString,String className) throws Exception{
        XMLStreamReader reader = StAXUtils.createXMLStreamReader(new ByteArrayInputStream(testString.getBytes()));
        Class clazz = Class.forName(className);
        Class[] declaredClasse = clazz.getDeclaredClasses();
        //ideally this should be 1
        Class innerClazz = declaredClasse[0];
        Method parseMethod = innerClazz.getMethod("parse",new Class[]{XMLStreamReader.class});
        Object obj = parseMethod.invoke(null,new Object[]{reader});
        assertNotNull(obj);

        return obj;

    }

    protected  String className= null;
    protected Class propertyClass = null;

    /**
     * check value function - may be overridden
     * @param xmlToSet
     * @param value
     * @throws Exception
     */
    protected void checkValue(String xmlToSet, String value) throws Exception {
        Object o = process(xmlToSet, className);
        Class beanClass = Class.forName(className);

        BeanInfo info = Introspector.getBeanInfo(beanClass);
        PropertyDescriptor[] propDescs = info.getPropertyDescriptors();
        for (int i = 0; i < propDescs.length; i++) {
            PropertyDescriptor propDesc = propDescs[i];

            if  (propDesc.getPropertyType().equals(propertyClass)){
                String s = convertToString(propDesc.getReadMethod().invoke(o,
                        (Object[]) null));
                compare(value,s);
            }
        }


        CompareOMElemntSerializations(o, xmlToSet);
    }

    /**
     * Compares serializations - may be overridden
     * @param o
     * @param xmlToSet
     * @throws Exception
     */
    protected void CompareOMElemntSerializations(Object o, String xmlToSet) throws Exception {
        OMElement element = getOMElement(o);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(baos);
        element.serialize(writer);
        writer.flush();

        assertXMLEqual(baos.toString(),xmlToSet);
    }

    /**
     * Get OM element via reflection
     * @param bean
     * @return
     * @throws Exception
     */
    protected OMElement getOMElement(Object bean) throws Exception {
        Method method = bean.getClass().getMethod("getOMElement", new Class[]{
                javax.xml.namespace.QName.class,
                org.apache.axiom.om.OMFactory.class});

        return (OMElement) method.invoke(bean, new Object[]{null, OMAbstractFactory.getOMFactory()});

    }

    /**
     * comapare method - may be overridden
     * @param val1
     * @param val2
     */
    protected void compare(String val1,String val2){
        assertEquals(val1,val2);
    }

    /**
     *
     * @param o
     * @return
     */
    protected String convertToString(Object o){
        return o.toString();
    }
}