/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you 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 .
 */

package org.openoffice.xmerge.converter.xml.sxw.pocketword;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;

import org.openoffice.xmerge.ConvertData;
import org.openoffice.xmerge.ConvertException;
import org.openoffice.xmerge.Document;
import org.openoffice.xmerge.DocumentDeserializer;
import org.openoffice.xmerge.converter.xml.OfficeConstants;
import org.openoffice.xmerge.converter.xml.ParaStyle;
import org.openoffice.xmerge.converter.xml.StyleCatalog;
import org.openoffice.xmerge.converter.xml.TextStyle;
import org.openoffice.xmerge.converter.xml.sxw.SxwDocument;
import org.openoffice.xmerge.util.OfficeUtil;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;


/**
 * <p>Pocket Word implementation of <code>DocumentDeserializer</code>
 * for the {@link
 * org.openoffice.xmerge.converter.xml.sxw.pocketword.PluginFactoryImpl
 * PluginFactoryImpl}.</p>
 *
 * <p>This converts a Pocket Word file to an OpenOffice Writer XML DOM.</p>
 *
 * @author  Mark Murnane
 * @version 1.1
 */
public final class DocumentDeserializerImpl
            implements DocumentDeserializer, OfficeConstants {

    private PocketWordDocument pswDoc = null;
    private SxwDocument sxwDoc = null;
    private String docName;

    private StyleCatalog styleCat = null;


    /**
     * Initialises a new <code>DocumentDeserializerImpl</code> using the
     * supplied <code>ConvertData</code>.</p>
     *
     * <p>The <code>Document</code> objects in the <code>ConvertData</code>
     *    should be {@link
     *    org.openoffice.xmerge.converter.xml.sxw.pocketword.PocketWordDocument
     *    PocketWordDocument} objects.</p>
     *
     * @param   cd      ConvertData containing a <code>PocketWordDocument</code>
     *                  for conversion.
     */
    public DocumentDeserializerImpl(ConvertData cd) {
        Iterator<Object> e = cd.getDocumentEnumeration();

        // A Pocket Word file is composed of one binary file
        while (e.hasNext()) {
            pswDoc = (PocketWordDocument)e.next();
        }

        docName = pswDoc.getName();
    }


    /**
     *  <p>Convert the data passed into the <code>DocumentDeserializer</code>
     *  constructor into the OpenOffice Writer <code>Document</code>
     *  format.</p>
     *
     *  <p>This method may or may not be thread-safe.  It is expected
     *  that the user code does not call this method in more than one
     *  thread.  And for most cases, this method is only done once.</p>
     *
     *  @return  The resulting <code>Document</code> object from conversion.
     *
     *  @throws  ConvertException  If any Convert error occurs.
     *  @throws  IOException       If any I/O error occurs.
     */
    public Document deserialize() throws IOException, ConvertException {
        Iterator<Paragraph> pe = pswDoc.getParagraphEnumeration();

        sxwDoc = new SxwDocument (docName);
        sxwDoc.initContentDOM();

        // Default to an initial 5 entries in the catalog.
        styleCat = new StyleCatalog(5);

        try {
            buildDocument(pe);
        }
        catch (Exception e) {
            e.printStackTrace();
            throw new ConvertException("Error building OpenOffice Writer DOM: "
                                        + e.toString());

        }

        return sxwDoc;
    }


    /**
     * This method actually takes care of the conversion.
     *
     * @param   data    An Enumeration of all Paragraphs in the Pocket Word doc.
     *
     * @return  The OpenOffice Writer XML representation of the data.
     *
     * @throws  IOException     If any I/O errors occur.
     */
    private void buildDocument(Iterator<Paragraph> data) throws IOException {

        org.w3c.dom.Document doc = sxwDoc.getContentDOM();

        /*
         * There should be only one each of office:body and
         * office:automatic-styles in each document.
         */
        Node bodyNode = doc.getElementsByTagName(TAG_OFFICE_BODY).item(0);

        // Not every document has an automatic style tag
        Node autoStylesNode = doc.getElementsByTagName(
                                        TAG_OFFICE_AUTOMATIC_STYLES).item(0);
        if (autoStylesNode == null) {
            autoStylesNode = doc.createElement(TAG_OFFICE_AUTOMATIC_STYLES);
            doc.insertBefore(autoStylesNode, bodyNode);
        }


        // Needed for naming new styles
        int paraStyles = 1;
        int textStyles = 1;

        // Pocket Word has no concept of a list.
        Element listNode = null;


        // Down to business ...
        while (data.hasNext()) {
            Paragraph p = data.next();
            Element paraNode  = doc.createElement(TAG_PARAGRAPH);

            // Set paragraph style information here
            ParaStyle pStyle = p.makeStyle();
            if (pStyle == null) {
                paraNode.setAttribute(ATTRIBUTE_TEXT_STYLE_NAME,
                                        PocketWordConstants.DEFAULT_STYLE);
            }
            else {
                // Create paragraph style
                pStyle.setName(new String("PS" + paraStyles++));
                paraNode.setAttribute(ATTRIBUTE_TEXT_STYLE_NAME, pStyle.getName());
                styleCat.add(pStyle);
            }


            /*
             * For each of the paragraphs, process each segment.
             * There will always be at least one.
             */
            Iterator<ParagraphTextSegment> paraData = p.getSegmentsEnumerator();
            ArrayList<Element> textSpans = new ArrayList<Element>(0);

            do {
                ParagraphTextSegment pts = paraData.next();
                Element span = doc.createElement(OfficeConstants.TAG_SPAN);

                TextStyle ts = pts.getStyle();

                if (ts != null) {
                    ts.setName(new String("TS" + textStyles++));
                    span.setAttribute(ATTRIBUTE_TEXT_STYLE_NAME, ts.getName());
                    styleCat.add(ts);
                }
                else {
                    span.setAttribute(ATTRIBUTE_TEXT_STYLE_NAME,
                                        PocketWordConstants.DEFAULT_STYLE);
                }

                // If this isn't a blank paragraph
                if (pts.getText() != null && !pts.getText().equals("")) {
                    Node[] children = OfficeUtil.parseText(pts.getText(), doc);

                    for (int j = 0; j < children.length; j++) {
                        span.appendChild(children[j]);
                    }
                }

                textSpans.add(span);

            } while (paraData.hasNext());


            /*
             * Special case for the first span.  If it has no style, then
             * it shouldn't be a span, so just add its children with style
             * set as standard.
             */
            Element firstSpan = textSpans.get(0);
            String  styleName = firstSpan.getAttribute(ATTRIBUTE_TEXT_STYLE_NAME);
            if (styleName.equals(PocketWordConstants.DEFAULT_STYLE)) {
                NodeList nl = firstSpan.getChildNodes();
                int len = nl.getLength();

                for (int i = 0; i < len; i++) {
                    /*
                     * Always take item 0 as the DOM tree event model will
                     * cause the NodeList to shrink as each Node is reparented.
                     *
                     * By taking the first item from the list, we essentially
                     * traverse the list in order.
                     */
                    paraNode.appendChild(nl.item(0));
                }
            }
            else {
                paraNode.appendChild(firstSpan);
            }

            // The rest are spans, so just add them
            for (int i = 1; i < textSpans.size(); i++) {
                paraNode.appendChild(textSpans.get(i));
            }


            /*
             * Pocket Word doesn't support lists, but it does have bulleted
             * paragraphs that are essentially the same thing.
             *
             * Unlike OpenOffice Writer, a blank paragraph can be bulleted
             * as well.  This will be handled by inserting a blank paragraph
             * into the unordered list, but OpenOffice Writer will not display
             * an item at that point in the list.
             */
            if (p.isBulleted()) {
                if (listNode == null) {
                    listNode = doc.createElement(TAG_UNORDERED_LIST);
                }
                Element listItem = doc.createElement(TAG_LIST_ITEM);
                listItem.appendChild(paraNode);
                listNode.appendChild(listItem);
            }
            else {
                if (listNode != null) {
                    bodyNode.appendChild(listNode);
                    listNode = null;
                }
                bodyNode.appendChild(paraNode);
            }
        } // End processing paragraphs


        // Now write the style catalog to the document
        NodeList nl = styleCat.writeNode(doc, "dummy").getChildNodes();
        int nlLen = nl.getLength();     // nl.item reduces the length
        for (int i = 0; i < nlLen; i++) {
            autoStylesNode.appendChild(nl.item(0));
        }
    }
}