/*
 * Copyright 2005-2014 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.axiom;

import java.util.Iterator;
import javax.xml.namespace.QName;
import javax.xml.transform.Result;

import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMException;
import org.apache.axiom.om.OMNamespace;
import org.apache.axiom.soap.SOAPFactory;
import org.apache.axiom.soap.SOAPHeader;
import org.apache.axiom.soap.SOAPHeaderBlock;

import org.springframework.ws.soap.SoapHeader;
import org.springframework.ws.soap.SoapHeaderElement;
import org.springframework.ws.soap.SoapHeaderException;

/**
 * Axiom-specific version of {@code org.springframework.ws.soap.SoapHeader}.
 *
 * @author Arjen Poutsma
 * @since 1.0.0
 */
abstract class AxiomSoapHeader extends AxiomSoapElement implements SoapHeader {

	AxiomSoapHeader(SOAPHeader axiomHeader, SOAPFactory axiomFactory) {
		super(axiomHeader, axiomFactory);
	}

	@Override
	public Result getResult() {
		return new AxiomResult(getAxiomHeader(), getAxiomFactory());
	}

	@Override
	public SoapHeaderElement addHeaderElement(QName name) {
		try {
			OMNamespace namespace =
					getAxiomFactory().createOMNamespace(name.getNamespaceURI(),
							name.getPrefix());
			SOAPHeaderBlock axiomHeaderBlock = getAxiomHeader().addHeaderBlock(name.getLocalPart(), namespace);
			return new AxiomSoapHeaderElement(axiomHeaderBlock, getAxiomFactory());
		}
		catch (OMException ex) {
			throw new AxiomSoapHeaderException(ex);
		}
	}

	@Override
	public void removeHeaderElement(QName name) throws SoapHeaderException {
		try {
			OMElement element = getAxiomHeader().getFirstChildWithName(name);
			if (element != null) {
				element.detach();
			}
		}
		catch (OMException ex) {
			throw new AxiomSoapHeaderException(ex);
		}
	}

	@Override
	@SuppressWarnings("unchecked")
	public Iterator<SoapHeaderElement> examineMustUnderstandHeaderElements(String role) {
		try {
			return new AxiomSoapHeaderElementIterator(getAxiomHeader().examineMustUnderstandHeaderBlocks(role));
		}
		catch (OMException ex) {
			throw new AxiomSoapHeaderException(ex);
		}
	}

	@Override
	@SuppressWarnings("unchecked")
	public Iterator<SoapHeaderElement> examineAllHeaderElements() {
		try {
			return new AxiomSoapHeaderElementIterator(getAxiomHeader().examineAllHeaderBlocks());
		}
		catch (OMException ex) {
			throw new AxiomSoapHeaderException(ex);
		}
	}

	@Override
	@SuppressWarnings("unchecked")
	public Iterator<SoapHeaderElement> examineHeaderElements(QName name) throws SoapHeaderException {
		try {
			return new AxiomSoapHeaderElementIterator(getAxiomHeader().getChildrenWithName(name));
		}
		catch (OMException ex) {
			throw new AxiomSoapHeaderException(ex);
		}
	}

	protected SOAPHeader getAxiomHeader() {
		return (SOAPHeader) getAxiomElement();
	}

	protected class AxiomSoapHeaderElementIterator implements Iterator<SoapHeaderElement> {

		private final Iterator<SOAPHeaderBlock> axiomIterator;

		protected AxiomSoapHeaderElementIterator(Iterator<SOAPHeaderBlock> axiomIterator) {
			this.axiomIterator = axiomIterator;
		}

		@Override
		public boolean hasNext() {
			return axiomIterator.hasNext();
		}

		@Override
		public SoapHeaderElement next() {
			try {
				SOAPHeaderBlock axiomHeaderBlock = axiomIterator.next();
				return new AxiomSoapHeaderElement(axiomHeaderBlock, getAxiomFactory());
			}
			catch (OMException ex) {
				throw new AxiomSoapHeaderException(ex);
			}
		}

		@Override
		public void remove() {
			axiomIterator.remove();
		}
	}
}