/*

 * Copyright (c) 2003, 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

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

 * questions.

 */

package com.sun.tools.doclets.internal.toolkit.builders;

import java.io.*;

import java.util.*;

import javax.xml.parsers.*;

import org.xml.sax.*;

import org.xml.sax.helpers.DefaultHandler;

import com.sun.tools.doclets.internal.toolkit.*;

import com.sun.tools.doclets.internal.toolkit.util.*;

/**

 * Parse the XML that specified the order of operation for the builders.  This

 * Parser uses SAX parsing.

 *

 *  <p><b>This is NOT part of any supported API.

 *  If you write code that depends on this, you do so at your own risk.

 *  This code and its internal interfaces are subject to change or

 *  deletion without notice.</b>

 *

 * @author Jamie Ho

 * @since 1.5

 * @see SAXParser

 */

public class LayoutParser extends DefaultHandler {

    /**

     * The map of XML elements that have been parsed.

     */

    private Map<String,XMLNode> xmlElementsMap;

    private XMLNode currentNode;

    private final Configuration configuration;

    private String currentRoot;

    private boolean isParsing;

    private LayoutParser(Configuration configuration) {

        this.configuration = configuration;

    }

    /**

     * Return an instance of the BuilderXML.

     *

     * @param configuration the current configuration of the doclet.

     * @return an instance of the BuilderXML.

     */

    public static LayoutParser getInstance(Configuration configuration) {

        return new LayoutParser(configuration);

    }

    /**

     * Parse the XML specifying the layout of the documentation.

     *

     * @return the list of XML elements parsed.

     */

    public XMLNode parseXML(String root) {

        if (xmlElementsMap.containsKey(root)) {

            return xmlElementsMap.get(root);

        }

        try {

            currentRoot = root;

            isParsing = false;

            SAXParserFactory factory = SAXParserFactory.newInstance();

            SAXParser saxParser = factory.newSAXParser();

            InputStream in = configuration.getBuilderXML();

            saxParser.parse(in, this);

            return xmlElementsMap.get(root);

        } catch (Throwable t) {

            t.printStackTrace();

            throw new DocletAbortException(t);

        }

    }

    /**

     * {@inheritDoc}

     */

    @Override

    public void startElement(String namespaceURI, String sName, String qName,

        Attributes attrs)

    throws SAXException {

        if (isParsing || qName.equals(currentRoot)) {

            isParsing = true;

            currentNode = new XMLNode(currentNode, qName);

            for (int i = 0; i < attrs.getLength(); i++)

                currentNode.attrs.put(attrs.getLocalName(i), attrs.getValue(i));

            if (qName.equals(currentRoot))

                xmlElementsMap.put(qName, currentNode);

        }

    }

    /**

     * {@inheritDoc}

     */

    @Override

    public void endElement(String namespaceURI, String sName, String qName)

    throws SAXException {

        if (! isParsing) {

            return;

        }

        currentNode = currentNode.parent;

        isParsing = ! qName.equals(currentRoot);

    }

}