/*
 * $Id$
 * Copyright (C) 2001 The Apache Software Foundation. All rights reserved.
 * For details on use and redistribution please refer to the
 * LICENSE file included with these sources.
 */
package org.apache.fop.fonts.apps;

import java.io.*;
import org.w3c.dom.*;
import org.apache.xerces.dom.*;
import org.apache.xml.serialize.*;
import org.apache.xalan.xslt.*;
import org.apache.fop.fonts.*;
import java.util.Hashtable;
import java.util.Vector;
import java.util.Enumeration;

/**
 * A tool which reads TTF files and generates
 * XML font metrics file for use in FOP.
 *
 */
public class TTFReader {

    private boolean invokedStandalone = false;

    public TTFReader() {}


    /**
     * Parse commandline arguments. put options in the Hashtable and return
     * arguments in the String array
     * the arguments: -fn Perpetua,Bold -cn PerpetuaBold per.ttf Perpetua.xml
     * returns a String[] with the per.ttf and Perpetua.xml. The hash
     * will have the (key, value) pairs: (-fn, Perpetua) and (-cn, PerpetuaBold)
     */
    private static String[] parseArguments(Hashtable options, String[] args) {
        Vector arguments = new Vector();
        for (int i = 0; i < args.length; i++) {
            if (args[i].startsWith("-")) {
                if ((i + 1) < args.length &&!args[i + 1].startsWith("-")) {
                    options.put(args[i], args[i + 1]);
                    i++;
                } else {
                    options.put(args[i], "");
                }
            } else {
                arguments.addElement(args[i]);
            }
        }

        String[] argStrings = new String[arguments.size()];
        arguments.copyInto(argStrings);
        return argStrings;
    }


    private final static void displayUsage() {
        System.out.println(" java org.apache.fop.fonts.apps.TTFReader [options] fontfile.ttf xmlfile.xml\n");
        System.out.println(" where options can be:\n");
        System.out.println("-enc ansi");
        System.out.println("     With this option you create a WinAnsi encoded font.\n");
        System.out.println("     The default is to create a CID keyed font.");
        System.out.println("     If you're not going to use characters outside the");
        System.out.println("     pdfencoding range (almost the same as iso-8889-1)");
        System.out.println("     you can add this option.");
        System.out.println("-ttcname <fontname>");
        System.out.println("     If you're reading data from a TrueType Collection");
        System.out.println("     (.ttc file) you must specify which font from the");
        System.out.println("     collection you will read metrics from. If you read");
        System.out.println("     from a .ttc file without this option, the fontnames");
        System.out.println("      will be listed for you.");
        System.out.println(" -fn <fontname>\n");
        System.out.println("     default is to use the fontname in the .ttf file, but\n"
                           + "     you can override that name to make sure that the\n");
        System.out.println("     embedded font is used (if you're embedding fonts)\n");
        System.out.println("     instead of installed fonts when viewing documents with Acrobat Reader.\n");
    }


    /**
     * The main method for the TTFReader tool.
     *
     * @param  args Command-line arguments: [options] fontfile.ttf xmlfile.xml
     * where options can be:
     * -fn <fontname>
     * default is to use the fontname in the .ttf file, but you can override
     * that name to make sure that the embedded font is used instead of installed
     * fonts when viewing documents with Acrobat Reader.
     * -cn <classname>
     * default is to use the fontname
     * -ef <path to the truetype fontfile>
     * will add the possibility to embed the font. When running fop, fop will look
     * for this file to embed it
     * -er <path to truetype fontfile relative to org/apache/fop/render/pdf/fonts>
     * you can also include the fontfile in the fop.jar file when building fop.
     * You can use both -ef and -er. The file specified in -ef will be searched first,
     * then the -er file.
     */
    public static void main(String[] args) {
        String embFile = null;
        String embResource = null;
        String className = null;
        String fontName = null;
        String ttcName = null;
        boolean isCid = true;

        Hashtable options = new Hashtable();
        String[] arguments = parseArguments(options, args);

        TTFReader app = new TTFReader();
        app.invokedStandalone = true;

        System.out.println("TTF Reader v1.1.1");
        System.out.println();

        if (options.get("-enc") != null) {
            String enc = (String)options.get("-enc");
            if ("ansi".equals(enc))
                isCid = false;
        }

        if (options.get("-ttcname") != null)
            ttcName = (String)options.get("-ttcname");

        if (options.get("-ef") != null)
            embFile = (String)options.get("-ef");

        if (options.get("-er") != null)
            embResource = (String)options.get("-er");

        if (options.get("-fn") != null)
            fontName = (String)options.get("-fn");

        if (options.get("-cn") != null)
            className = (String)options.get("-cn");

        if (arguments.length != 2 || options.get("-h") != null
            || options.get("-help") != null || options.get("--help") != null)
            displayUsage();
        else {
            TTFFile ttf = app.loadTTF(arguments[0], ttcName);
            if (ttf != null) {
                org.w3c.dom.Document doc = app.constructFontXML(ttf,
                        fontName, className, embResource, embFile, isCid,
                        ttcName);

                if (isCid)
                    System.out.println("Creating CID encoded metrics");
                else
                    System.out.println("Creating WinAnsi encoded metrics");

                if (doc != null) {
                    app.writeFontXML(doc, arguments[1]);
                }

                if (ttf.isEmbeddable())
                    System.out.println("This font contains no embedding license restrictions");
                else
                    System.out.println("** Note: This font contains license retrictions for\n"
                                       + "         embedding. This font shouldn't be embedded.");

            }
        }
    }

    /**
     * Read a TTF file and returns it as an object.
     *
     * @param   filename The filename of the PFM file.
     * @return  The TTF as an object.
     */
    public TTFFile loadTTF(String fileName, String fontName) {
        TTFFile ttfFile = new TTFFile();
        try {
            System.out.println("Reading " + fileName + "...");
            System.out.println();

            FontFileReader reader = new FontFileReader(fileName);
            ttfFile.readFont(reader, fontName);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        return ttfFile;
    }


    /**
     * Writes the generated DOM Document to a file.
     *
     * @param   doc The DOM Document to save.
     * @param   target The target filename for the XML file.
     */
    public void writeFontXML(org.w3c.dom.Document doc, String target) {
        System.out.println("Writing xml font file " + target + "...");
        System.out.println();

        try {
            OutputFormat format = new OutputFormat(doc);    // Serialize DOM
            FileWriter out = new FileWriter(target);    // Writer will be a String
            XMLSerializer serial = new XMLSerializer(out, format);
            serial.asDOMSerializer();                       // As a DOM Serializer

            serial.serialize(doc.getDocumentElement());
            out.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Generates the font metrics file from the TTF/TTC file.
     *
     * @param   ttf The PFM file to generate the font metrics from.
     * @return  The DOM document representing the font metrics file.
     */
    public org.w3c.dom.Document constructFontXML(TTFFile ttf,
            String fontName, String className, String resource, String file,
            boolean isCid, String ttcName) {
        System.out.println("Creating xml font file...");
        System.out.println();

        Document doc = new DocumentImpl();
        Element root = doc.createElement("font-metrics");
        doc.appendChild(root);
        if (isCid)
            root.setAttribute("type", "TYPE0");
        else
            root.setAttribute("type", "TRUETYPE");

        Element el = doc.createElement("font-name");
        root.appendChild(el);

        // Note that the PostScript name usually is something like
        // "Perpetua-Bold", but the TrueType spec says that in the ttf file
        // it should be "Perpetua,Bold".

        String s = stripWhiteSpace(ttf.getPostscriptName());

        if (fontName != null)
            el.appendChild(doc.createTextNode(stripWhiteSpace(fontName)));
        else
            el.appendChild(doc.createTextNode(s));

        el = doc.createElement("embed");
        root.appendChild(el);
        if (file != null && ttf.isEmbeddable())
            el.setAttribute("file", file);
        if (resource != null && ttf.isEmbeddable())
            el.setAttribute("class", resource);

        el = doc.createElement("cap-height");
        root.appendChild(el);
        el.appendChild(doc.createTextNode(String.valueOf(ttf.getCapHeight())));

        el = doc.createElement("x-height");
        root.appendChild(el);
        el.appendChild(doc.createTextNode(String.valueOf(ttf.getXHeight())));

        el = doc.createElement("ascender");
        root.appendChild(el);
        el.appendChild(doc.createTextNode(String.valueOf(ttf.getLowerCaseAscent())));

        el = doc.createElement("descender");
        root.appendChild(el);
        el.appendChild(doc.createTextNode(String.valueOf(ttf.getLowerCaseDescent())));

        Element bbox = doc.createElement("bbox");
        root.appendChild(bbox);
        int[] bb = ttf.getFontBBox();
        String[] names = {
            "left", "bottom", "right", "top"
        };
        for (int i = 0; i < 4; i++) {
            el = doc.createElement(names[i]);
            bbox.appendChild(el);
            el.appendChild(doc.createTextNode(String.valueOf(bb[i])));
        }

        el = doc.createElement("flags");
        root.appendChild(el);
        el.appendChild(doc.createTextNode(String.valueOf(ttf.getFlags())));

        el = doc.createElement("stemv");
        root.appendChild(el);
        el.appendChild(doc.createTextNode(ttf.getStemV()));

        el = doc.createElement("italicangle");
        root.appendChild(el);
        el.appendChild(doc.createTextNode(ttf.getItalicAngle()));

        if (ttcName != null) {
            el = doc.createElement("ttc-name");
            root.appendChild(el);
            el.appendChild(doc.createTextNode(ttcName));
        }

        el = doc.createElement("subtype");
        root.appendChild(el);

        // Fill in extras for CID keyed fonts
        if (isCid) {
            el.appendChild(doc.createTextNode("TYPE0"));

            Element mel = doc.createElement("multibyte-extras");
            root.appendChild(mel);

            el = doc.createElement("cid-type");
            mel.appendChild(el);
            el.appendChild(doc.createTextNode("CIDFontType2"));

            el = doc.createElement("default-width");
            mel.appendChild(el);
            el.appendChild(doc.createTextNode("0"));

            el = doc.createElement("bfranges");
            mel.appendChild(el);
            for (Enumeration e = ttf.getCMaps().elements();
                    e.hasMoreElements(); ) {
                TTFCmapEntry ce = (TTFCmapEntry)e.nextElement();
                Element el2 = doc.createElement("bf");
                el.appendChild(el2);
                el2.setAttribute("us", String.valueOf(ce.unicodeStart));
                el2.setAttribute("ue", String.valueOf(ce.unicodeEnd));
                el2.setAttribute("gi", String.valueOf(ce.glyphStartIndex));
            }

            el = doc.createElement("cid-widths");
            el.setAttribute("start-index", "0");
            mel.appendChild(el);

            int[] wx = ttf.getWidths();
            for (int i = 0; i < wx.length; i++) {
                Element wxel = doc.createElement("wx");
                wxel.setAttribute("w", String.valueOf(wx[i]));
                el.appendChild(wxel);
            }
        } else {
            // Fill in extras for singlebyte fonts
            el.appendChild(doc.createTextNode("TRUETYPE"));

            Element sel = doc.createElement("singlebyte-extras");
            root.appendChild(sel);

            el = doc.createElement("encoding");
            sel.appendChild(el);
            el.appendChild(doc.createTextNode(ttf.getCharSetName()));

            el = doc.createElement("first-char");
            sel.appendChild(el);
            el.appendChild(doc.createTextNode(String.valueOf(ttf.getFirstChar())));

            el = doc.createElement("last-char");
            sel.appendChild(el);
            el.appendChild(doc.createTextNode(String.valueOf(ttf.getLastChar())));

            Element widths = doc.createElement("widths");
            sel.appendChild(widths);

            for (short i = ttf.getFirstChar(); i <= ttf.getLastChar(); i++) {
                el = doc.createElement("char");
                widths.appendChild(el);
                el.setAttribute("idx", String.valueOf(i));
                el.setAttribute("wdt", String.valueOf(ttf.getCharWidth(i)));
            }
        }

        // Get kerning
        Enumeration enum;
        if (isCid)
            enum = ttf.getKerning().keys();
        else
            enum = ttf.getAnsiKerning().keys();

        while (enum.hasMoreElements()) {
            Integer kpx1 = (Integer)enum.nextElement();

            el = doc.createElement("kerning");
            el.setAttribute("kpx1", kpx1.toString());
            root.appendChild(el);
            Element el2 = null;

            Hashtable h2;
            if (isCid)
                h2 = (Hashtable)ttf.getKerning().get(kpx1);
            else
                h2 = (Hashtable)ttf.getAnsiKerning().get(kpx1);

            for (Enumeration enum2 = h2.keys(); enum2.hasMoreElements(); ) {
                Integer kpx2 = (Integer)enum2.nextElement();
                if (isCid || kpx2.intValue() < 256) {
                    el2 = doc.createElement("pair");
                    el2.setAttribute("kpx2", kpx2.toString());
                    Integer val = (Integer)h2.get(kpx2);
                    el2.setAttribute("kern", val.toString());
                    el.appendChild(el2);
                }
            }
        }

        return doc;
    }


    private String stripWhiteSpace(String s) {
        char[] ch = new char[s.length()];
        s.getChars(0, s.length(), ch, 0);
        StringBuffer stb = new StringBuffer();
        for (int i = 0; i < ch.length; i++)
            if (ch[i] != ' ' && ch[i] != '\r' && ch[i] != '\n'
                    && ch[i] != '\t')
                stb.append(ch[i]);

        return stb.toString();
    }

    private String escapeString(String str) {
        StringBuffer esc = new StringBuffer();

        for (int i = 0; i < str.length(); i++) {
            if (str.charAt(i) == '\\')
                esc.append("\\\\");
            else
                esc.append(str.charAt(i));
        }

        return esc.toString();
    }

}