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package org.openoffice.xmerge.converter.xml.sxc;

import org.w3c.dom.NodeList;
import org.w3c.dom.Node;
import org.w3c.dom.Element;

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

import org.openoffice.xmerge.Document;
import org.openoffice.xmerge.ConvertData;
import org.openoffice.xmerge.ConvertException;
import org.openoffice.xmerge.DocumentDeserializer;
import org.openoffice.xmerge.converter.xml.OfficeConstants;
import org.openoffice.xmerge.converter.xml.sxc.SxcDocument;
import org.openoffice.xmerge.converter.xml.sxc.BookSettings;
import org.openoffice.xmerge.converter.xml.sxc.NameDefinition;
import org.openoffice.xmerge.converter.xml.sxc.CellStyle;
import org.openoffice.xmerge.converter.xml.Style;
import org.openoffice.xmerge.converter.xml.StyleCatalog;
import org.openoffice.xmerge.util.Debug;

/**
 *  <p>General spreadsheet implementation of <code>DocumentDeserializer</code>
 *  for the {@link
 *  org.openoffice.xmerge.converter.xml.sxc.SxcPluginFactory
 *  SxcPluginFactory}.  Used with SXC <code>Document</code> objects.</p>
 *
 *  <p>The <code>deserialize</code> method uses a <code>DocDecoder</code>
 *  to read the device spreadsheet format into a <code>String</code>
 *  object, then it calls <code>buildDocument</code> to create a
 *  <code>SxcDocument</code> object from it.</p>
 *
 *  @author      Paul Rank
 *  @author      Mark Murnane
 *  @author      Martin Maher 
 */
public abstract class SxcDocumentDeserializer implements OfficeConstants,
    DocumentDeserializer {

    /**
     *  A <code>SpreadsheetDecoder</code> object for decoding from
     *  device formats.
     */
    private SpreadsheetDecoder decoder = null;

    /**  A w3c <code>Document</code>. */
    private org.w3c.dom.Document settings = null;

    /**  A w3c <code>Document</code>. */
    private org.w3c.dom.Document doc = null;

    /**  An <code>ConvertData</code> object assigned to this object. */
    private ConvertData cd = null;
    
    /** A style catalog for the workbook  */
    private StyleCatalog styleCat = null;

    private int textStyles = 1;
    private int colStyles = 1;
    private int rowStyles = 1;
    
    /**
     *  Constructor.
     *
     *  @param  cd  <code>ConvertData</code> consisting of a
     *              device content object.
     */
    public SxcDocumentDeserializer(ConvertData cd) {
        this.cd = cd;
    }


    /** 
     *  This abstract method will be implemented by concrete subclasses
     *  and will return an application-specific Decoder.
     *
     *  @param  workbook  The WorkBook to read.
     *  @param  password  The WorkBook password.
     *
     *  @return  The appropriate <code>SpreadSheetDecoder</code>.
     *
     *  @throws  IOException  If any I/O error occurs.
     */
    public abstract SpreadsheetDecoder createDecoder(String workbook, String[] worksheetNames, String password)
        throws IOException;

    
    /**
     *  <p>This method will return the name of the WorkBook from the
     *  <code>ConvertData</code>.  Allows for situations where the
     *  WorkBook name differs from the Device Content name.</p>
     *
     *  <p>Implemented in the Deserializer as the Decoder's constructor requires
     *  a name.</p>
     *
     *  @param  cd  The <code>ConvertData</code> containing the Device 
     *              content.
     *
     *  @return  The WorkBook name.
     */
    protected abstract String getWorkbookName(ConvertData cd) throws IOException;

    
    /**
     *  This method will return the name of the WorkSheet from the
     *  <code>ConvertData</code>.
     *
     *  @param  cd  The <code>ConvertData</code> containing the Device
     *              content.
     *
     *  @return  The WorkSheet names.
     */
    protected abstract String[] getWorksheetNames(ConvertData cd) throws IOException;
    
    
    /**
     *  <p>Method to convert a set of &quot;Device&quot;
     *  <code>Document</code> objects into a <code>SxcDocument</code>
     *  object and returns it as a <code>Document</code>.</p>
     *
     *  <p>This method is not thread safe for performance reasons.
     *  This method should not be called from within two threads.
     *  It would be best to call this method only once per object
     *  instance.</p>
     *
     *  @return  document  An <code>SxcDocument</code> consisting
     *                     of the data converted from the input
     *                     stream.
     *
     *  @throws  ConvertException  If any conversion error occurs.
     *  @throws  IOException       If any I/O error occurs.
     */
    public Document deserialize() throws ConvertException,
        IOException {

        // Get the name of the WorkBook from the ConvertData.
        String[] worksheetNames = getWorksheetNames(cd);
        String workbookName = getWorkbookName(cd);

        // Create a document
        SxcDocument sxcDoc = new SxcDocument(workbookName);
        sxcDoc.initContentDOM();
        sxcDoc.initSettingsDOM();

        // Default to an initial 5 entries in the catalog.  
        styleCat = new StyleCatalog(5);
        
        doc = sxcDoc.getContentDOM();
        settings = sxcDoc.getSettingsDOM();
        initFontTable();
        // Little fact for the curious reader: workbookName should
        // be the name of the StarCalc file minus the file extension suffix.

        // Create a Decoder to decode the DeviceContent to a spreadsheet document
        // TODO - we aren't using a password in StarCalc, so we can
        // use any value for password here.  If StarCalc XML supports
        // passwords in the future, we should try to get the correct
        // password value here.
        //
        decoder = createDecoder(workbookName, worksheetNames, "password");

        Debug.log(Debug.TRACE, "<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
        Debug.log(Debug.TRACE, "<DEBUGLOG>");

        decoder.addDeviceContent(cd);
        decode();

        Debug.log(Debug.TRACE, "</DEBUGLOG>");

        return sxcDoc;
    }

    /**
     * This initializes a font table so we can imclude some basic font
     * support for spreadsheets.
     *
     */
    private void initFontTable() {
    
        String fontTable[]= new String[] {	"Tahoma", "Tahoma", "swiss", "variable",
                                            "Courier New", "&apos;Courier New&apos;", "modern", "fixed"};
        //  Traverse to the office:body element.
        //  There should only be one.
        NodeList list = doc.getElementsByTagName(TAG_OFFICE_FONT_DECLS);
        Node root = list.item(0);
    
        for(int i=0;i<fontTable.length;) {

            // Create an element node for the table
            Element tableElement = (Element) doc.createElement(TAG_STYLE_FONT_DECL);

            tableElement.setAttribute(ATTRIBUTE_STYLE_NAME, fontTable[i++]);
               tableElement.setAttribute(ATTRIBUTE_FO_FONT_FAMILY, fontTable[i++]);
               tableElement.setAttribute(ATTRIBUTE_FO_FONT_FAMILY_GENERIC, fontTable[i++]);
            tableElement.setAttribute(ATTRIBUTE_STYLE_FONT_PITCH, fontTable[i++]);

               root.appendChild(tableElement);
        }

    }

    /**
     *  Outer level method used to decode a WorkBook
     *  into a <code>Document</code>.
     *
     *  @throws  IOException  If any I/O error occurs.
     */
    protected void decode() throws IOException {

        // Get number of worksheets
        int numSheets = decoder.getNumberOfSheets();
        // #i33702# - check for an Empty InputStream.
        if(numSheets == 0)
        {
            System.err.println("Error decoding invalid Input stream");
            return;
        }

        //  Traverse to the office:body element.
        //  There should only be one.
        NodeList list = doc.getElementsByTagName(TAG_OFFICE_BODY);
        Node node = list.item(0);

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

            // Set the decoder to the correct worksheet
            decoder.setWorksheet(i);

            int len = list.getLength();

            if (len > 0) {

                // Process the spreadsheet
                processTable(node);
            }
        }
        
        // Add the Defined Name table if there is one 
        Enumeration nameDefinitionTable = decoder.getNameDefinitions();
        if(nameDefinitionTable.hasMoreElements()) {
            processNameDefinition(node, nameDefinitionTable);
        }

        // add settings
        NodeList settingsList = settings.getElementsByTagName(TAG_OFFICE_SETTINGS);
        Node settingsNode = settingsList.item(0);;		
        processSettings(settingsNode);

    }
    

    
    /**
     *  This method process the settings portion
     *  of the <code>Document</code>.  
     *
     *  @param  root  The root <code>Node</code> of the
     *                <code>Document</code> we are building.  This
     *                <code>Node</code> should be a TAG_OFFICE_SETTINGS
     *                tag.
     */
    protected void processSettings(Node root) {
    
        Element configItemSetEntry		= (Element) settings.createElement(TAG_CONFIG_ITEM_SET);
        configItemSetEntry.setAttribute(ATTRIBUTE_CONFIG_NAME, "view-settings");
        Element configItemMapIndexed	= (Element) settings.createElement(TAG_CONFIG_ITEM_MAP_INDEXED);
        configItemMapIndexed.setAttribute(ATTRIBUTE_CONFIG_NAME, "Views");
        Element configItemMapEntry		= (Element) settings.createElement(TAG_CONFIG_ITEM_MAP_ENTRY);
        BookSettings bs = (BookSettings) decoder.getSettings();
        bs.writeNode(settings, configItemMapEntry);
    
        configItemMapIndexed.appendChild(configItemMapEntry);
        configItemSetEntry.appendChild(configItemMapIndexed);
        root.appendChild(configItemSetEntry);
    }
    
    /**
     *  This method process a Name Definition Table and generates a portion
     *  of the <code>Document</code>.  
     *
     *  @param  root  The root <code>Node</code> of the
     *                <code>Document</code> we are building.  This
     *                <code>Node</code> should be a TAG_OFFICE_BODY
     *                tag.
     *
     *  @throws  IOException  If any I/O error occurs.
     */
    protected void processNameDefinition(Node root, Enumeration eNameDefinitions) throws IOException {

        Debug.log(Debug.TRACE, "<NAMED-EXPRESSIONS>");

        Element namedExpressionsElement = (Element) doc.createElement(TAG_NAMED_EXPRESSIONS);

        while(eNameDefinitions.hasMoreElements()) {

            NameDefinition tableEntry = (NameDefinition) eNameDefinitions.nextElement();
            tableEntry.writeNode(doc, namedExpressionsElement);
        }

        root.appendChild(namedExpressionsElement);

        Debug.log(Debug.TRACE, "</NAMED-EXPRESSIONS>");
    }
    
    /**
     *  This method process a WorkSheet and generates a portion
     *  of the <code>Document</code>.  A spreadsheet is represented
     *  as a table Node in StarOffice XML format.
     *
     *  @param  root  The root <code>Node</code> of the
     *                <code>Document</code> we are building.  This
     *                <code>Node</code> should be a TAG_OFFICE_BODY
     *                tag.
     *
     *  @throws  IOException  If any I/O error occurs.
     */
    protected void processTable(Node root) throws IOException {

        Debug.log(Debug.TRACE, "<TABLE>");

        // Create an element node for the table
        Element tableElement = (Element) doc.createElement(TAG_TABLE);

        // Get the sheet name
        String sheetName = decoder.getSheetName();

        // Set the table name attribute
        tableElement.setAttribute(ATTRIBUTE_TABLE_NAME, sheetName);

        // TODO - style currently hardcoded - get real value
        // Set table style-name attribute
        tableElement.setAttribute(ATTRIBUTE_TABLE_STYLE_NAME, "Default");

        // Append the table element to the root node
        root.appendChild(tableElement);

        Debug.log(Debug.TRACE, "<SheetName>" + sheetName + "</SheetName>");

        // add the various different table-columns
        processColumns(tableElement);
        
        // Get each cell and add to doc
        processCells(tableElement);

        Debug.log(Debug.TRACE, "</TABLE>");
    }

    /**
     *  <p>This method process the cells in a <code>Document</code>
     *  and generates a portion of the <code>Document</code>.</p>
     *
     *  <p>This method assumes that records are sorted by
     *  row and then column.</p>
     *
     *  @param  root  The <code>Node</code> of the <code>Document</code>
     *                we are building that we will append our cell
     *                <code>Node</code> objects.  This <code>Node</code>
     *                should be a TAG_TABLE tag.
     *
     *  @throws  IOException  If any I/O error occurs.
     */
    protected void processColumns(Node root) throws IOException {

        for(Enumeration e = decoder.getColumnRowInfos();e.hasMoreElements();) {
        
            ColumnRowInfo ci = (ColumnRowInfo) e.nextElement();
            if(ci.isColumn()) {
                ColumnStyle cStyle = new ColumnStyle("Default",SxcConstants.COLUMN_STYLE_FAMILY,
                            SxcConstants.DEFAULT_STYLE, ci.getSize(), null);

                Style result[] = (Style[]) styleCat.getMatching(cStyle);
                String styleName;
                if(result.length==0) {
                
                        cStyle.setName("co" + colStyles++);
                        styleName = cStyle.getName();
                        Debug.log(Debug.TRACE,"No existing style found, adding " + styleName);
                        styleCat.add(cStyle);
                } else {
                        ColumnStyle existingStyle = (ColumnStyle) result[0];
                        styleName = existingStyle.getName();
                        Debug.log(Debug.TRACE,"Existing style found : " + styleName);
                }

                // Create an element node for the new row
                Element colElement = (Element) doc.createElement(TAG_TABLE_COLUMN);
                colElement.setAttribute(ATTRIBUTE_TABLE_STYLE_NAME, styleName);
                if(ci.getRepeated()!=1) {
                    String repeatStr = String.valueOf(ci.getRepeated());
                    colElement.setAttribute(ATTRIBUTE_TABLE_NUM_COLUMNS_REPEATED, repeatStr);
                }
                root.appendChild(colElement);
            }
        }
    }

    /**
     *  <p>This method process the cells in a <code>Document</code>
     *  and generates a portion of the <code>Document</code>.</p>
     *
     *  <p>This method assumes that records are sorted by
     *  row and then column.</p>
     *
     *  @param  root  The <code>Node</code> of the <code>Document</code>
     *                we are building that we will append our cell
     *                <code>Node</code> objects.  This <code>Node</code>
     *                should be a TAG_TABLE tag.
     *
     *  @throws  IOException  If any I/O error occurs.
     */
    protected void processCells(Node root) throws IOException {

        // The current row element
        Element rowElement = null;

        // The current cell element
        Element cellElement = null;

        // The row number - we may not have any rows (empty sheet)
        // so set to zero.
        int row = 0;

        // The column number - This is the expected column number of
        // the next cell we are reading.
        int col = 1;

        // The number of columns in the spreadsheet
        int lastColumn = decoder.getNumberOfColumns();
        
        // 
        Node autoStylesNode = null;

        // Loop over all cells in the spreadsheet
        while (decoder.goToNextCell()) {

            // Get the row number
            int newRow = decoder.getRowNumber();

            // Is the cell in a new row, or part of the current row?
            if (newRow != row) {

                // Make sure that all the cells in the previous row
                // have been entered.
                if (col <= lastColumn && rowElement != null) {
                    int numSkippedCells = lastColumn - col + 1;
                    addEmptyCells(numSkippedCells, rowElement);
                }

                // log an end row - if we already have a row
                if (row != 0) {
                    Debug.log(Debug.TRACE, "</tr>");
                }

                // How far is the new row from the last row?
                int deltaRows = newRow - row;

                // Check if we have skipped any rows
                if (deltaRows > 1) {
                    // Add in empty rows
                    addEmptyRows(deltaRows-1, root, lastColumn);
                }

                // Re-initialize column (since we are in a new row)
                col = 1;

                // Create an element node for the new row
                rowElement = (Element) doc.createElement(TAG_TABLE_ROW);


                for(Enumeration e = decoder.getColumnRowInfos();e.hasMoreElements();) {
                    ColumnRowInfo cri = (ColumnRowInfo) e.nextElement();
                    if(cri.isRow() && cri.getRepeated()==newRow-1) {
                        // We have the correct Row BIFFRecord for this row
                        RowStyle rStyle = new RowStyle("Default",SxcConstants.ROW_STYLE_FAMILY,
                                    SxcConstants.DEFAULT_STYLE, cri.getSize(), null);

                        Style result[] = (Style[]) styleCat.getMatching(rStyle);
                        String styleName;
                        if(result.length==0) {
                    
                                rStyle.setName("ro" + rowStyles++);
                                styleName = rStyle.getName();
                                Debug.log(Debug.TRACE,"No existing style found, adding " + styleName);
                                styleCat.add(rStyle);
                        } else {
                                RowStyle existingStyle = (RowStyle) result[0];
                                styleName = existingStyle.getName();
                                Debug.log(Debug.TRACE,"Existing style found : " + styleName);
                        }						
                        rowElement.setAttribute(ATTRIBUTE_TABLE_STYLE_NAME, styleName);
                        // For now we will not use the repeat column attribute
                    }
                }
        
                // Append the row element to the root node
                root.appendChild(rowElement);

                // Update row number
                row = newRow;

                Debug.log(Debug.TRACE, "<tr>");
            }

            // Get the column number of the current cell
            int newCol = decoder.getColNumber();

            // Check to see if some columns were skipped
            if (newCol != col) {

                // How many columns have we skipped?
                int numColsSkipped = newCol - col;

                addEmptyCells(numColsSkipped, rowElement);

                // Update the column number to account for the
                // skipped cells
                col = newCol;
            }

            // Lets start dealing with the cell data
            Debug.log(Debug.TRACE, "<td>");

            // Get the cell's contents
            String cellContents = decoder.getCellContents();

            // Get the type of the data in the cell
            String cellType = decoder.getCellDataType();

            // Get the cell format 
            Format fmt = decoder.getCellFormat();

            // Create an element node for the cell
            cellElement = (Element) doc.createElement(TAG_TABLE_CELL);

            Node bodyNode = doc.getElementsByTagName(TAG_OFFICE_BODY).item(0);

            // Not every document has an automatic style tag
            autoStylesNode = doc.getElementsByTagName(
                                        TAG_OFFICE_AUTOMATIC_STYLES).item(0);

            if (autoStylesNode == null) {
                autoStylesNode = doc.createElement(TAG_OFFICE_AUTOMATIC_STYLES);
                doc.insertBefore(autoStylesNode, bodyNode);
               }
            
            CellStyle tStyle = new
            CellStyle(	"Default",SxcConstants.TABLE_CELL_STYLE_FAMILY,
                        SxcConstants.DEFAULT_STYLE, fmt, null);
            String styleName;
            Style result[] = (Style[]) styleCat.getMatching(tStyle);
            if(result.length==0) {
                
                    tStyle.setName("ce" + textStyles++);
                    styleName = tStyle.getName();
                    Debug.log(Debug.TRACE,"No existing style found, adding " + styleName);
                    styleCat.add(tStyle);
            } else {
                    CellStyle existingStyle = (CellStyle) result[0];
                    styleName = existingStyle.getName();
                    Debug.log(Debug.TRACE,"Existing style found : " + styleName);
            }
            
            cellElement.setAttribute(ATTRIBUTE_TABLE_STYLE_NAME, styleName);
            
            // Store the cell data into the appropriate attributes
            processCellData(cellElement, cellType, cellContents);

            // Append the cell element to the row node
            rowElement.appendChild(cellElement);

            // Append the cellContents as a text node
            Element textElement = (Element) doc.createElement(TAG_PARAGRAPH);
            cellElement.appendChild(textElement);
            textElement.appendChild(doc.createTextNode(cellContents));

            Debug.log(Debug.TRACE, cellContents);
            Debug.log(Debug.TRACE, "</td>");

            // Increment to the column number of the next expected cell
            col++;
        }

        // Make sure that the last row is padded correctly
        if (col <= lastColumn && rowElement != null) {
            int numSkippedCells = lastColumn - col + 1;
            addEmptyCells(numSkippedCells, rowElement);
        }
        
        // Now write the style catalog to the document
        if(autoStylesNode!=null) {
            Debug.log(Debug.TRACE,"Well the autostyle node was found!!!");
            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));
        }
        }

        if (row != 0) {

            // The sheet does have rows, so write out a /tr
            Debug.log(Debug.TRACE, "</tr>");
        }
    }


    /**
     *  This method will add empty rows to the <code>Document</code>.
     *  It is called when the conversion process encounters
     *  a row (or rows) that do not contain any data in its cells.
     *
     *  @param  numEmptyRows   The number of empty rows that we 
     *                         need to add to the <code>Document</code>.
     *  @param  root           The <code>Node</code> of the
     *                         <code>Document</code> we are building
     *                         that we will append our empty row
     *                         <code>Node</code> objects.  This
     *                         <code>Node</code> should be a TAG_TABLE
     *                         tag.
     *  @param  numEmptyCells  The number of empty cells in the
     *                         empty row.
     */
    protected void addEmptyRows(int numEmptyRows, Node root, int numEmptyCells) {

        // Create an element node for the row
        Element rowElement = (Element) doc.createElement(TAG_TABLE_ROW);

        // TODO - style currently hardcoded - get real value
        // Set row style-name attribute
        rowElement.setAttribute(ATTRIBUTE_TABLE_STYLE_NAME, "Default");

        // Set cell number-rows-repeated attribute
        rowElement.setAttribute(ATTRIBUTE_TABLE_NUM_ROWS_REPEATED,
                                Integer.toString(numEmptyRows));

        // Append the row element to the root node
        root.appendChild(rowElement);

        // Open Office requires the empty row to have an empty cell (or cells)
        addEmptyCells(numEmptyCells, rowElement);

        // Write empty rows to the log
        for (int i = 0;  i < numEmptyRows; i++) {
            Debug.log(Debug.TRACE, "<tr />");
        }

    }


    /**
     *  This method will add empty cells to the <code>Document</code>.
     *  It is called when the conversion process encounters a row
     *  that contains some cells without data.
     *
     *  @param   numColsSkipped  The number of empty cells
     *                           that we need to add to the
     *                           current row.
     *  @param   row             The <code>Node</code> of the
     *                           <code>Document</code> we
     *                           are building that we will 
     *                           append our empty cell
     *                           <code>Node</code> objects.
     *                           This <code>Node</code> should
     *                           be a TAG_TABLE_ROW tag.
     */
    protected void addEmptyCells(int numColsSkipped, Node row) {

        // Create an empty cellElement
        Element cellElement = (Element) doc.createElement(TAG_TABLE_CELL);

        // TODO - style currently hardcoded - get real value
        // Set cell style-name attribute
        cellElement.setAttribute(ATTRIBUTE_TABLE_STYLE_NAME, "Default");

        // If we skipped more than 1 cell, we must set the
        // appropriate attribute
        if (numColsSkipped > 1) {

            // Set cell number-columns-repeated attribute
            cellElement.setAttribute(ATTRIBUTE_TABLE_NUM_COLUMNS_REPEATED,
                                     Integer.toString(numColsSkipped));
        }

        // Append the empty cell element to the row node
        row.appendChild(cellElement);

        // Write empty cells to the log
        for (int i = 0;  i < numColsSkipped; i++) {
            Debug.log(Debug.TRACE, "<td />");
        }
    }


    /**
     *  This method process the data in a cell and sets
     *  the appropriate attributes on the cell <code>Element</code>.
     *
     *  @param   cellElement  A TAG_TABLE_CELL <code>Element</code>
     *                        that we will be adding attributes to 
     *                        based on the type of data in the cell.
     *  @param   type         The type of data contained in the cell.
     *  @param   contents     The contents of the data contained in
     *                        the cell.
     */
    protected void processCellData(Element cellElement, String type,
                                 String contents) {

        // Set cell value-type attribute
        cellElement.setAttribute(ATTRIBUTE_TABLE_VALUE_TYPE, type);

        // Does the cell contain a formula?
        if (contents.startsWith("=")) {

            cellElement.setAttribute(ATTRIBUTE_TABLE_FORMULA, contents);

            cellElement.setAttribute(ATTRIBUTE_TABLE_VALUE, decoder.getCellValue());
            // String data does not require any additional attributes
        } else if (!type.equals(CELLTYPE_STRING)) {

            if (type.equals(CELLTYPE_TIME)) {

                // Data returned in StarOffice XML format, so store in
                // attribute
                cellElement.setAttribute(ATTRIBUTE_TABLE_TIME_VALUE,
                                         contents);

            } else if (type.equals(CELLTYPE_DATE)) {

                // Data returned in StarOffice XML format, so store in
                // attribute
                cellElement.setAttribute(ATTRIBUTE_TABLE_DATE_VALUE,
                                         contents);

            } else if (type.equals(CELLTYPE_BOOLEAN)) {

                // StarOffice XML format requires stored boolean value 
                // to be in lower case
                cellElement.setAttribute(ATTRIBUTE_TABLE_BOOLEAN_VALUE,
                                         contents.toLowerCase());

            } else if (type.equals(CELLTYPE_CURRENCY)) {
                // TODO - StarOffice XML format requires a correct style to
                // display currencies correctly.  Need to implement styles.
                // TODO - USD is for US currencies.  Need to pick up
                // the correct currency location from the source file.
                cellElement.setAttribute(ATTRIBUTE_TABLE_CURRENCY, "USD");

                // Data comes stripped of currency symbols
                cellElement.setAttribute(ATTRIBUTE_TABLE_VALUE, contents);

            } else if (type.equals(CELLTYPE_PERCENT)) {
                // Data comes stripped of percent signs
                cellElement.setAttribute(ATTRIBUTE_TABLE_VALUE, contents);

            } else {
                // Remaining data types use table-value attribute

                cellElement.setAttribute(ATTRIBUTE_TABLE_VALUE, contents);
            }
        }
    }

}

