/*

 * Copyright (c) 2005, 2006, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.org.apache.xalan.internal.xsltc.trax;

import java.io.IOException;

import java.util.Hashtable;

import java.util.Stack;

import java.util.Vector;

import java.util.Iterator;

import org.xml.sax.Attributes;

import org.xml.sax.ContentHandler;

import org.xml.sax.DTDHandler;

import org.xml.sax.EntityResolver;

import org.xml.sax.ErrorHandler;

import org.xml.sax.InputSource;

import org.xml.sax.Locator;

import org.xml.sax.SAXException;

import org.xml.sax.SAXNotRecognizedException;

import org.xml.sax.SAXNotSupportedException;

import org.xml.sax.XMLReader;

import org.xml.sax.ext.LexicalHandler;

import org.xml.sax.ext.Locator2;

import org.xml.sax.helpers.AttributesImpl;

import com.sun.org.apache.xalan.internal.xsltc.dom.SAXImpl;

import javax.xml.namespace.QName;

import javax.xml.stream.XMLStreamReader;

import javax.xml.stream.XMLStreamConstants;

import javax.xml.stream.XMLStreamException;

import javax.xml.stream.events.Attribute;

import javax.xml.stream.events.Characters;

import javax.xml.stream.events.EndElement;

import javax.xml.stream.events.Namespace;

import javax.xml.stream.events.ProcessingInstruction;

import javax.xml.stream.events.StartElement;

import javax.xml.stream.events.StartDocument;

import javax.xml.stream.events.XMLEvent;

/**

 * @author Padmaja Vedula

 * @author Sunitha Reddy

 */

public class StAXStream2SAX implements XMLReader, Locator {

    //private final static String EMPTYSTRING = "";

    //private static final String XMLNS_PREFIX = "xmlns";

    // StAX Stream source

    private final XMLStreamReader staxStreamReader;

    //private Node _dom = null;

    private ContentHandler _sax = null;

    private LexicalHandler _lex = null;

    private SAXImpl _saxImpl = null;

    //private Hashtable _nsPrefixes = new Hashtable();

    public StAXStream2SAX(XMLStreamReader staxSrc) {

            staxStreamReader = staxSrc;

    }

    public ContentHandler getContentHandler() {

        return _sax;

    }

    public void setContentHandler(ContentHandler handler) throws

        NullPointerException

    {

        _sax = handler;

        if (handler instanceof LexicalHandler) {

            _lex = (LexicalHandler) handler;

        }

        if (handler instanceof SAXImpl) {

            _saxImpl = (SAXImpl)handler;

        }

    }

    public void parse(InputSource unused) throws IOException, SAXException {

        try {

            bridge();

        } catch (XMLStreamException e) {

            throw new SAXException(e);

        }

    }

    //Main Work Starts Here.

    public void parse() throws IOException, SAXException, XMLStreamException {

        bridge();

    }

   /**

     * This class is only used internally so this method should never

     * be called.

     */

    public void parse(String sysId) throws IOException, SAXException {

        throw new IOException("This method is not yet implemented.");

    }

   public void bridge() throws XMLStreamException {

        try {

            // remembers the nest level of elements to know when we are done.

            int depth=0;

            // skip over START_DOCUMENT

            int event = staxStreamReader.getEventType();

            if (event == XMLStreamConstants.START_DOCUMENT) {

                event = staxStreamReader.next();

            }

            // If not a START_ELEMENT (e.g., a DTD), skip to next tag

            if (event != XMLStreamConstants.START_ELEMENT) {

                event = staxStreamReader.nextTag();

                // An error if a START_ELEMENT isn't found now

                if (event != XMLStreamConstants.START_ELEMENT) {

                    throw new IllegalStateException("The current event is " +

                            "not START_ELEMENT\n but" + event);

                }

            }

            handleStartDocument();

            do {

                // These are all of the events listed in the javadoc for

                // XMLEvent.

                // The spec only really describes 11 of them.

                switch (event) {

                    case XMLStreamConstants.START_ELEMENT :

                        depth++;

                        handleStartElement();

                        break;

                    case XMLStreamConstants.END_ELEMENT :

                        handleEndElement();

                        depth--;

                        break;

                    case XMLStreamConstants.CHARACTERS :

                        handleCharacters();

                        break;

                    case XMLStreamConstants.ENTITY_REFERENCE :

                        handleEntityReference();

                        break;

                    case XMLStreamConstants.PROCESSING_INSTRUCTION :

                        handlePI();

                        break;

                    case XMLStreamConstants.COMMENT :

                        handleComment();

                        break;

                    case XMLStreamConstants.DTD :

                        handleDTD();

                        break;

                    case XMLStreamConstants.ATTRIBUTE :

                        handleAttribute();

                        break;

                    case XMLStreamConstants.NAMESPACE :

                        handleNamespace();

                        break;

                    case XMLStreamConstants.CDATA :

                        handleCDATA();

                        break;

                    case XMLStreamConstants.ENTITY_DECLARATION :

                        handleEntityDecl();

                        break;

                    case XMLStreamConstants.NOTATION_DECLARATION :

                        handleNotationDecl();

                        break;

                    case XMLStreamConstants.SPACE :

                        handleSpace();

                        break;

                    default :

                        throw new InternalError("processing event: " + event);

                }

                event=staxStreamReader.next();

            } while (depth!=0);

            handleEndDocument();

        } catch (SAXException e) {

            throw new XMLStreamException(e);

        }

    }

    private void handleEndDocument() throws SAXException {

        _sax.endDocument();

    }

    private void handleStartDocument() throws SAXException {

        _sax.setDocumentLocator(new Locator2() {

            public int getColumnNumber() {

                return staxStreamReader.getLocation().getColumnNumber();

            }

            public int getLineNumber() {

                return staxStreamReader.getLocation().getLineNumber();

            }

            public String getPublicId() {

                return staxStreamReader.getLocation().getPublicId();

            }

            public String getSystemId() {

                return staxStreamReader.getLocation().getSystemId();

            }

            public String getXMLVersion() {

                return staxStreamReader.getVersion();

            }

            public String getEncoding() {

                return staxStreamReader.getEncoding();

            }

         });

        _sax.startDocument();

    }

    private void handlePI() throws XMLStreamException {

        try {

            _sax.processingInstruction(

                staxStreamReader.getPITarget(),

                staxStreamReader.getPIData());

        } catch (SAXException e) {

            throw new XMLStreamException(e);

        }

    }

    private void handleCharacters() throws XMLStreamException {

        // workaround for bugid 5046319 - switch over to commented section

        // below when it is fixed.

        int textLength = staxStreamReader.getTextLength();

        char[] chars = new char[textLength];

        staxStreamReader.getTextCharacters(0, chars, 0, textLength);

        try {

            _sax.characters(chars, 0, chars.length);

        } catch (SAXException e) {

            throw new XMLStreamException(e);

        }

//        int start = 0;

//        int len;

//        do {

//            len = staxStreamReader.getTextCharacters(start, buf, 0, buf.length);

//            start += len;

//            try {

//                _sax.characters(buf, 0, len);

//            } catch (SAXException e) {

//                throw new XMLStreamException(e);

//            }

//        } while (len == buf.length);

    }

    private void handleEndElement() throws XMLStreamException {

        QName qName = staxStreamReader.getName();

        try {

            //construct prefix:localName from qName

            String qname = "";

            if (qName.getPrefix() != null && qName.getPrefix().trim().length() != 0){

                qname = qName.getPrefix() + ":";

            }

            qname += qName.getLocalPart();

            // fire endElement

            _sax.endElement(

                qName.getNamespaceURI(),

                qName.getLocalPart(),

                qname);

            // end namespace bindings

            int nsCount = staxStreamReader.getNamespaceCount();

            for (int i = nsCount - 1; i >= 0; i--) {

                String prefix = staxStreamReader.getNamespacePrefix(i);

                if (prefix == null) { // true for default namespace

                    prefix = "";

                }

                _sax.endPrefixMapping(prefix);

            }

        } catch (SAXException e) {

            throw new XMLStreamException(e);

        }

    }

    private void handleStartElement() throws XMLStreamException {

        try {

            // start namespace bindings

            int nsCount = staxStreamReader.getNamespaceCount();

            for (int i = 0; i < nsCount; i++) {

                String prefix = staxStreamReader.getNamespacePrefix(i);

                if (prefix == null) { // true for default namespace

                    prefix = "";

                }

                _sax.startPrefixMapping(

                    prefix,

                    staxStreamReader.getNamespaceURI(i));

            }

            // fire startElement

            QName qName = staxStreamReader.getName();

            String prefix = qName.getPrefix();

            String rawname;

            if(prefix==null || prefix.length()==0)

                rawname = qName.getLocalPart();

            else

                rawname = prefix + ':' + qName.getLocalPart();

            Attributes attrs = getAttributes();

            _sax.startElement(

                qName.getNamespaceURI(),

                qName.getLocalPart(),

                rawname,

                attrs);

        } catch (SAXException e) {

            throw new XMLStreamException(e);

        }

    }

    /**

     * Get the attributes associated with the given START_ELEMENT or ATTRIBUTE

     * StAXevent.

     *

     * @return the StAX attributes converted to an org.xml.sax.Attributes

     */

    private Attributes getAttributes() {

        AttributesImpl attrs = new AttributesImpl();

        int eventType = staxStreamReader.getEventType();

        if (eventType != XMLStreamConstants.ATTRIBUTE

            && eventType != XMLStreamConstants.START_ELEMENT) {

            throw new InternalError(

                "getAttributes() attempting to process: " + eventType);

        }

        // in SAX, namespace declarations are not part of attributes by default.

        // (there's a property to control that, but as far as we are concerned

        // we don't use it.) So don't add xmlns:* to attributes.

        // gather non-namespace attrs

        for (int i = 0; i < staxStreamReader.getAttributeCount(); i++) {

            String uri = staxStreamReader.getAttributeNamespace(i);

            if(uri==null)   uri="";

            String localName = staxStreamReader.getAttributeLocalName(i);

            String prefix = staxStreamReader.getAttributePrefix(i);

            String qName;

            if(prefix==null || prefix.length()==0)

                qName = localName;

            else

                qName = prefix + ':' + localName;

            String type = staxStreamReader.getAttributeType(i);

            String value = staxStreamReader.getAttributeValue(i);

            attrs.addAttribute(uri, localName, qName, type, value);

        }

        return attrs;

    }

    private void handleNamespace() {

        // no-op ???

        // namespace events don't normally occur outside of a startElement

        // or endElement

    }

    private void handleAttribute() {

        // no-op ???

        // attribute events don't normally occur outside of a startElement

        // or endElement

    }

    private void handleDTD() {

        // no-op ???

        // it seems like we need to pass this info along, but how?

    }

    private void handleComment() {

        // no-op ???

    }

    private void handleEntityReference() {

        // no-op ???

    }

    private void handleSpace() {

        // no-op ???

        // this event is listed in the javadoc, but not in the spec.

    }

    private void handleNotationDecl() {

        // no-op ???

        // this event is listed in the javadoc, but not in the spec.

    }

    private void handleEntityDecl() {

        // no-op ???

        // this event is listed in the javadoc, but not in the spec.

    }

    private void handleCDATA() {

        // no-op ???

        // this event is listed in the javadoc, but not in the spec.

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public DTDHandler getDTDHandler() {

        return null;

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public ErrorHandler getErrorHandler() {

        return null;

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public boolean getFeature(String name) throws SAXNotRecognizedException,

        SAXNotSupportedException

    {

        return false;

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public void setFeature(String name, boolean value) throws

        SAXNotRecognizedException, SAXNotSupportedException

    {

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public void setDTDHandler(DTDHandler handler) throws NullPointerException {

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public void setEntityResolver(EntityResolver resolver) throws

        NullPointerException

    {

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public EntityResolver getEntityResolver() {

        return null;

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public void setErrorHandler(ErrorHandler handler) throws

        NullPointerException

    {

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public void setProperty(String name, Object value) throws

        SAXNotRecognizedException, SAXNotSupportedException {

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public Object getProperty(String name) throws SAXNotRecognizedException,

        SAXNotSupportedException

    {

        return null;

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */

    public int getColumnNumber() {

        return 0;

    }

    /**

     * This class is only used internally so this method should never

     * be called.

     */