/*
 * Copyright 2005-2010 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.springframework.ws.soap.stroap;

import java.util.List;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.XMLEvent;

import org.springframework.util.Assert;
import org.springframework.xml.stream.AbstractXMLEventWriter;

/**
 * @author Arjen Poutsma
 */
class CachingXMLEventWriter extends AbstractXMLEventWriter {

	private int elementDepth = 0;

	boolean startElementSeen = false;

	private final List<XMLEvent> events;

	CachingXMLEventWriter(List<XMLEvent> events) {
		Assert.notNull(events, "'events' must not be null");
		this.events = events;
	}

	public void add(XMLEvent event) throws XMLStreamException {
		if (event.isStartElement()) {
			startElementSeen = true;
			elementDepth++;
		}
		else if (event.isEndElement()) {
			elementDepth--;
		}
		else if (event.isStartDocument() || event.isEndDocument()) {
			return;
		}
		if (elementDepth >= 0 && startElementSeen) {
			events.add(event);
		}
	}
}