package org.apache.poi.xssf.usermodel;

import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.util.HashMap;
import java.util.Map;

import org.apache.poi.ss.usermodel.TableStyle;
import org.apache.poi.util.DocumentHelper;
import org.apache.poi.util.IOUtils;
import org.apache.poi.xssf.model.StylesTable;
import org.apache.xmlbeans.XmlOptions;
import org.openxmlformats.schemas.spreadsheetml.x2006.main.CTDxfs;
import org.openxmlformats.schemas.spreadsheetml.x2006.main.CTTableStyle;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.ls.DOMImplementationLS;
import org.w3c.dom.ls.LSSerializer;

/**
 * Table style names defined in the OOXML spec.  
 * The actual styling is defined in presetTableStyles.xml
 */
public enum XSSFBuiltinTableStyle {
    /***/
    TableStyleDark1,
    /***/
    TableStyleDark2,
    /***/
    TableStyleDark3,
    /***/
    TableStyleDark4,
    /***/
    TableStyleDark5,
    /***/
    TableStyleDark6,
    /***/
    TableStyleDark7,
    /***/
    TableStyleDark8,
    /***/
    TableStyleDark9,
    /***/
    TableStyleDark10,
    /***/
    TableStyleDark11,
    /***/
    TableStyleLight1,
    /***/
    TableStyleLight2,
    /***/
    TableStyleLight3,
    /***/
    TableStyleLight4,
    /***/
    TableStyleLight5,
    /***/
    TableStyleLight6,
    /***/
    TableStyleLight7,
    /***/
    TableStyleLight8,
    /***/
    TableStyleLight9,
    /***/
    TableStyleLight10,
    /***/
    TableStyleLight11,
    /***/
    TableStyleLight12,
    /***/
    TableStyleLight13,
    /***/
    TableStyleLight14,
    /***/
    TableStyleLight15,
    /***/
    TableStyleLight16,
    /***/
    TableStyleLight17,
    /***/
    TableStyleLight18,
    /***/
    TableStyleLight19,
    /***/
    TableStyleLight20,
    /***/
    TableStyleLight21,
    /***/
    TableStyleMedium1,
    /***/
    TableStyleMedium2,
    /***/
    TableStyleMedium3,
    /***/
    TableStyleMedium4,
    /***/
    TableStyleMedium5,
    /***/
    TableStyleMedium6,
    /***/
    TableStyleMedium7,
    /***/
    TableStyleMedium8,
    /***/
    TableStyleMedium9,
    /***/
    TableStyleMedium10,
    /***/
    TableStyleMedium11,
    /***/
    TableStyleMedium12,
    /***/
    TableStyleMedium13,
    /***/
    TableStyleMedium14,
    /***/
    TableStyleMedium15,
    /***/
    TableStyleMedium16,
    /***/
    TableStyleMedium17,
    /***/
    TableStyleMedium18,
    /***/
    TableStyleMedium19,
    /***/
    TableStyleMedium20,
    /***/
    TableStyleMedium21,
    /***/
    TableStyleMedium22,
    /***/
    TableStyleMedium23,
    /***/
    TableStyleMedium24,
    /***/
    TableStyleMedium25,
    /***/
    TableStyleMedium26,
    /***/
    TableStyleMedium27,
    /***/
    TableStyleMedium28,
    /***/
    PivotStyleMedium1,
    /***/
    PivotStyleMedium2,
    /***/
    PivotStyleMedium3,
    /***/
    PivotStyleMedium4,
    /***/
    PivotStyleMedium5,
    /***/
    PivotStyleMedium6,
    /***/
    PivotStyleMedium7,
    /***/
    PivotStyleMedium8,
    /***/
    PivotStyleMedium9,
    /***/
    PivotStyleMedium10,
    /***/
    PivotStyleMedium11,
    /***/
    PivotStyleMedium12,
    /***/
    PivotStyleMedium13,
    /***/
    PivotStyleMedium14,
    /***/
    PivotStyleMedium15,
    /***/
    PivotStyleMedium16,
    /***/
    PivotStyleMedium17,
    /***/
    PivotStyleMedium18,
    /***/
    PivotStyleMedium19,
    /***/
    PivotStyleMedium20,
    /***/
    PivotStyleMedium21,
    /***/
    PivotStyleMedium22,
    /***/
    PivotStyleMedium23,
    /***/
    PivotStyleMedium24,
    /***/
    PivotStyleMedium25,
    /***/
    PivotStyleMedium26,
    /***/
    PivotStyleMedium27,
    /***/
    PivotStyleMedium28,
    /***/
    PivotStyleLight1,
    /***/
    PivotStyleLight2,
    /***/
    PivotStyleLight3,
    /***/
    PivotStyleLight4,
    /***/
    PivotStyleLight5,
    /***/
    PivotStyleLight6,
    /***/
    PivotStyleLight7,
    /***/
    PivotStyleLight8,
    /***/
    PivotStyleLight9,
    /***/
    PivotStyleLight10,
    /***/
    PivotStyleLight11,
    /***/
    PivotStyleLight12,
    /***/
    PivotStyleLight13,
    /***/
    PivotStyleLight14,
    /***/
    PivotStyleLight15,
    /***/
    PivotStyleLight16,
    /***/
    PivotStyleLight17,
    /***/
    PivotStyleLight18,
    /***/
    PivotStyleLight19,
    /***/
    PivotStyleLight20,
    /***/
    PivotStyleLight21,
    /***/
    PivotStyleLight22,
    /***/
    PivotStyleLight23,
    /***/
    PivotStyleLight24,
    /***/
    PivotStyleLight25,
    /***/
    PivotStyleLight26,
    /***/
    PivotStyleLight27,
    /***/
    PivotStyleLight28,
    /***/
    PivotStyleDark1,
    /***/
    PivotStyleDark2,
    /***/
    PivotStyleDark3,
    /***/
    PivotStyleDark4,
    /***/
    PivotStyleDark5,
    /***/
    PivotStyleDark6,
    /***/
    PivotStyleDark7,
    /***/
    PivotStyleDark8,
    /***/
    PivotStyleDark9,
    /***/
    PivotStyleDark10,
    /***/
    PivotStyleDark11,
    /***/
    PivotStyleDark12,
    /***/
    PivotStyleDark13,
    /***/
    PivotStyleDark14,
    /***/
    PivotStyleDark15,
    /***/
    PivotStyleDark16,
    /***/
    PivotStyleDark17,
    /***/
    PivotStyleDark18,
    /***/
    PivotStyleDark19,
    /***/
    PivotStyleDark20,
    /***/
    PivotStyleDark21,
    /***/
    PivotStyleDark22,
    /***/
    PivotStyleDark23,
    /***/
    PivotStyleDark24,
    /***/
    PivotStyleDark25,
    /***/
    PivotStyleDark26,
    /***/
    PivotStyleDark27,
    /***/
    PivotStyleDark28,
   ;
    
    private static final Map<XSSFBuiltinTableStyle, TableStyle> styleMap = new HashMap<XSSFBuiltinTableStyle, TableStyle>(60);
    
    private XSSFBuiltinTableStyle() {
    }
    
    /**
     * @return built-in {@link TableStyle} definition
     */
    public TableStyle getStyle() {
        init();
        return styleMap.get(this);
    }
    
    /**
     * NOTE: only checks by name, not definition.
     * @param style
     * @return true if the style represents a built-in style, false if it is null or a custom style
     */
    public static boolean isBuiltinStyle(TableStyle style) {
        if (style == null) return false;
        try {
            XSSFBuiltinTableStyle.valueOf(style.getName());
            return true;
        } catch (IllegalArgumentException e) {
            return false;
        }
    }
    /**
     * Only init once - thus the synchronized.  Lazy, after creating instances,
     * and only when a style is actually needed, to avoid overhead for uses
     * that don't need the actual style definitions.
     * <p/>
     * Public so clients can initialize the map on startup rather than lazily
     * during evaluation if desired.
     */
    public static final synchronized void init() {
        if (! styleMap.isEmpty()) return; 
        
        /*
         * initialize map.  Every built-in has this format:
         * <styleName>
         *   <dxfs>
         *     <dxf>...</dxf>
         *     ...
         *   </dxfs>
         *   <tableStyles count="1">
         *     <tableStyle>...</tableStyle>
         *   </tableStyles>
         * </styleName>
         */
        try {
            final InputStream is = XSSFBuiltinTableStyle.class.getResourceAsStream("presetTableStyles.xml");
            try {
                final Document doc = DocumentHelper.readDocument(is);
                final NodeList styleNodes = doc.getDocumentElement().getChildNodes();
                for (int i=0; i < styleNodes.getLength(); i++) {
                    final Node node = styleNodes.item(i);
                    if (node.getNodeType() != Node.ELEMENT_NODE) continue; // only care about elements
                    final Element tag = (Element) node;
                    String styleName = tag.getTagName();
                    Node dxfsNode = tag.getElementsByTagName("dxfs").item(0);
                    Node tableStyleNode = tag.getElementsByTagName("tableStyles").item(0);

                    // hack because I can't figure out how to get XMLBeans to parse a sub-element in a standalone manner
                    // - build a fake styles.xml file with just this built-in
                    StylesTable styles = new StylesTable();
                    styles.readFrom(new ByteArrayInputStream(styleXML(dxfsNode, tableStyleNode).getBytes(Charset.forName("UTF-8"))));
                    styleMap.put(XSSFBuiltinTableStyle.valueOf(styleName), styles.getExplicitTableStyle(styleName));
                }
            } finally {
                IOUtils.closeQuietly(is);
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
    
    private static String styleXML(Node dxfsNode, Node tableStyleNode) {
        DOMImplementationLS lsImpl = (DOMImplementationLS)dxfsNode.getOwnerDocument().getImplementation().getFeature("LS", "3.0");
        LSSerializer lsSerializer = lsImpl.createLSSerializer();
        lsSerializer.getDomConfig().setParameter("xml-declaration", false);
        StringBuilder sb = new StringBuilder();
        sb.append("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n")
        .append("<styleSheet xmlns=\"http://schemas.openxmlformats.org/spreadsheetml/2006/main\" "
                + "xmlns:mc=\"http://schemas.openxmlformats.org/markup-compatibility/2006\" "
                + "xmlns:x14ac=\"http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac\" "
                + "xmlns:x16r2=\"http://schemas.microsoft.com/office/spreadsheetml/2015/02/main\" "
                + "mc:Ignorable=\"x14ac x16r2\">\n");
       sb.append(lsSerializer.writeToString(dxfsNode));
       sb.append(lsSerializer.writeToString(tableStyleNode));
       sb.append("</styleSheet>");
        return sb.toString(); 
    }
}