/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.sun.xml.internal.ws.api.addressing;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.Writer;

import com.sun.istack.internal.NotNull;
import com.sun.istack.internal.Nullable;
import com.sun.xml.internal.ws.message.AbstractHeaderImpl;
import com.sun.xml.internal.ws.util.xml.XmlUtil;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.xml.sax.ContentHandler;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;

import javax.xml.namespace.QName;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.soap.SOAPException;
import javax.xml.soap.SOAPMessage;
import javax.xml.soap.SOAPHeader;
import javax.xml.stream.XMLOutputFactory;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamWriter;
import javax.xml.transform.Transformer;
import javax.xml.transform.dom.DOMResult;

/**
 * Used to represent outbound endpoint reference header,
 * such as <ReplyTo> and <FaultTo>.
 * Used from {@link WSEndpointReference}.
 *
 * @author Kohsuke Kawaguchi
 * @see WSEndpointReference
 */
final class EPRHeader extends AbstractHeaderImpl {

    private final String nsUri,localName;
    private final WSEndpointReference epr;

    EPRHeader(QName tagName, WSEndpointReference epr) {
        this.nsUri = tagName.getNamespaceURI();
        this.localName = tagName.getLocalPart();
        this.epr = epr;
    }

    public @NotNull String getNamespaceURI() {
        return nsUri;
    }

    public @NotNull String getLocalPart() {
        return localName;
    }

    @Nullable
    public String getAttribute(@NotNull String nsUri, @NotNull String localName) {
        try {
            XMLStreamReader sr = epr.read("EndpointReference"/*doesn't matter*/);
            while(sr.getEventType()!= XMLStreamConstants.START_ELEMENT)
                sr.next();

            return sr.getAttributeValue(nsUri,localName);
        } catch (XMLStreamException e) {
            // since we are reading from buffer, this can't happen.
            throw new AssertionError(e);
        }
    }

    public XMLStreamReader readHeader() throws XMLStreamException {
        return epr.read(localName);
    }

    public void writeTo(XMLStreamWriter w) throws XMLStreamException {
        epr.writeTo(localName, w);
    }

    public void writeTo(SOAPMessage saaj) throws SOAPException {
        try {
            // TODO what about in-scope namespaces
            // Not very efficient consider implementing a stream buffer
            // processor that produces a DOM node from the buffer.
            Transformer t = XmlUtil.newTransformer();
            SOAPHeader header = saaj.getSOAPHeader();
            if (header == null)
                header = saaj.getSOAPPart().getEnvelope().addHeader();
// TODO workaround for oracle xdk bug 16555545, when this bug is fixed the line below can be
// uncommented and all lines below, except the catch block, can be removed.
//            t.transform(epr.asSource(localName), new DOMResult(header));
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            XMLStreamWriter w = XMLOutputFactory.newFactory().createXMLStreamWriter(baos);
            epr.writeTo(localName, w);
            w.flush();
            ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
            DocumentBuilderFactory fac = DocumentBuilderFactory.newInstance();
            fac.setNamespaceAware(true);
            Node eprNode = fac.newDocumentBuilder().parse(bais).getDocumentElement();
            Node eprNodeToAdd = header.getOwnerDocument().importNode(eprNode, true);
            header.appendChild(eprNodeToAdd);
        } catch (Exception e) {
            throw new SOAPException(e);
        }
    }

    public void writeTo(ContentHandler contentHandler, ErrorHandler errorHandler) throws SAXException {
        epr.writeTo(localName,contentHandler,errorHandler,true);
    }
}