/*
 * 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.
 * 
 */

package org.apache.jmeter.save;

import org.apache.jmeter.save.converters.ConversionHelp;
import org.apache.jorphan.collections.HashTree;

import com.thoughtworks.xstream.mapper.Mapper;
import com.thoughtworks.xstream.converters.ConversionException;
import com.thoughtworks.xstream.converters.Converter;
import com.thoughtworks.xstream.converters.MarshallingContext;
import com.thoughtworks.xstream.converters.UnmarshallingContext;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;

/**
 * Handles XStream conversion of Test Scripts
 * 
 */
public class ScriptWrapperConverter implements Converter {
    
	private static final String ATT_PROPERTIES = "properties"; // $NON-NLS-1$
    private static final String ATT_VERSION = "version"; // $NON-NLS-1$

    /**
	 * Returns the converter version; used to check for possible
	 * incompatibilities
	 */
	public static String getVersion() {
		return "$Revision: 656289 $"; // $NON-NLS-1$
	}

	Mapper classMapper;

	public ScriptWrapperConverter(Mapper classMapper) {
		this.classMapper = classMapper;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see com.thoughtworks.xstream.converters.Converter#canConvert(java.lang.Class)
	 */
	public boolean canConvert(Class arg0) {
		return arg0.equals(ScriptWrapper.class);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see com.thoughtworks.xstream.converters.Converter#marshal(java.lang.Object,
	 *      com.thoughtworks.xstream.io.HierarchicalStreamWriter,
	 *      com.thoughtworks.xstream.converters.MarshallingContext)
	 */
	public void marshal(Object arg0, HierarchicalStreamWriter writer, MarshallingContext context) {
		ScriptWrapper wrap = (ScriptWrapper) arg0;
		String version = SaveService.getVERSION();
        ConversionHelp.setOutVersion(version);// Ensure output follows version
		writer.addAttribute(ATT_VERSION, version);
		writer.addAttribute(ATT_PROPERTIES, SaveService.getPropertiesVersion());
		writer.startNode(classMapper.serializedClass(wrap.testPlan.getClass()));
		context.convertAnother(wrap.testPlan);
		writer.endNode();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see com.thoughtworks.xstream.converters.Converter#unmarshal(com.thoughtworks.xstream.io.HierarchicalStreamReader,
	 *      com.thoughtworks.xstream.converters.UnmarshallingContext)
	 */
	public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
		ScriptWrapper wrap = new ScriptWrapper();
		wrap.version = reader.getAttribute(ATT_VERSION);
		ConversionHelp.setInVersion(wrap.version);// Make sure decoding
													// follows input file
		reader.moveDown();
		// Catch errors and rethrow as ConversionException so we get location details
		try {
            wrap.testPlan = (HashTree) context.convertAnother(wrap, getNextType(reader));
        } catch (NoClassDefFoundError e) {
            throw createConversionException(e);
        } catch (Exception e) {
            throw createConversionException(e);
        }
		return wrap;
	}

    private ConversionException createConversionException(Throwable e) {
        final ConversionException conversionException = new ConversionException(e);
        StackTraceElement[] ste = e.getStackTrace();
        if (ste!=null){
            for(int i=0; i<ste.length; i++){
                StackTraceElement top=ste[i];
                String className=top.getClassName();
                if (className.startsWith("org.apache.jmeter.")){
                    conversionException.add("first-jmeter-class", top.toString());
                    break;
                }
            }
        }
        return conversionException;
    }

	protected Class getNextType(HierarchicalStreamReader reader) {
		String classAttribute = reader.getAttribute(ConversionHelp.ATT_CLASS);
		Class type;
		if (classAttribute == null) {
			type = classMapper.realClass(reader.getNodeName());
		} else {
			type = classMapper.realClass(classAttribute);
		}
		return type;
	}
}
