// Copyright 2002 Adam Megacz, see the COPYING file for licensing [GPL]
package org.xwt;

import java.io.*;
import java.util.*;
import org.xwt.util.*;

/** encapsulates a single XWF font */
public class XWF {

    /** all instances of XWF */
    private static Hash xwtfonts = new Hash();

    /** the int array comprising the XWF */
    int[] data = null;

    /** the width of the XWF's PNG */
    int w = 0;

    /** the height of the XWF's PNG */
    int h = 0;

    /** the full resource name of this font */
    String name = null;

    /** minimum descent of all glyphs */
    int maxascent = 0;

    /** maximum descent of all glyphs */
    int maxdescent = 0;

    /** hash containing all Picture instances created, keyed on an Integer object containing the argb color of the font */
    Hash pictures = new Hash();

    /** each element corresponds to a single glyph; <br>
     *  metrics[glyphnum][0] == x position of left edge of glyph<br>
     *  metrics[glyphnum][1] == x position of right edge of glyph<br>
     *  metrics[glyphnum][2] == y position of top edge of glyph<br>
     *  metrics[glyphnum][3] == y position of bottom edge of glyph<br>
     *  metrics[glyphnum][4] == advance amount<br>
     *  metrics[glyphnum][5] == baseline
     */
    int[][] metrics = null;

    /** drop all cached fonts when the theme mapping changes */
    public static void flushXWFs() { xwtfonts.clear(); }

    /** retrieve an XWF instance, creating it if needed */
    public static XWF getXWF(String resourcename) {
        XWF ret = (XWF)xwtfonts.get(resourcename);
        if (ret != null) return ret;

        String resolved = Resources.resolve(resourcename + ".xwf", null);
        byte[] bytes = Resources.getResource(resolved);
        if (bytes != null) {
            PNG png = PNG.decode(new ByteArrayInputStream(bytes), resourcename);
            if (png != null) return new XWF(resourcename, png);
        }
        return null;
    }

    public int getMaxAscent() { return maxascent; }
    public int getMaxDescent() { return maxdescent; }

    /** draws <tt>text</tt> on <tt>buf</tt> in this font, with color <tt>argb</tt> */
    public void drawString(DoubleBuffer buf, String text, int x, int y, int argb) {

        Integer color = new Integer(argb | 0xFF000000);
        Picture pg = (Picture)pictures.get(color);
        if (pg == null) {
            int[] data2 = new int[data.length];
            for(int i=0; i<data.length; i++)
                data2[i] = (data[i] & 0xFF000000) | (argb & 0x00FFFFFF);
            pg = Platform.createPicture(data2, w, h);
            pictures.put(color, pg);
        }

        int left = x;
        for(int i=0; i<text.length(); i++) {
            int c = "!\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~".indexOf(text.charAt(i));
            if (c == -1 || metrics[c] == null) {
        left += metrics[64] != null ? metrics[64][4] : 10;
        continue;
        }
            buf.drawPicture(pg,
                            left,
                            y - (metrics[c][5] - metrics[c][2]),
                            left + metrics[c][1] - metrics[c][0],
                            y - (metrics[c][5] - metrics[c][2]) + metrics[c][3] - metrics[c][2],
                            metrics[c][0], metrics[c][2], metrics[c][1], metrics[c][3]);
            
            left += metrics[c][4];
        }
    }

    /** returns the width of <tt>text</tt> when rendered in this font */
    public int stringWidth(String text) {
        int ret = 0;
        for(int i=0; i<text.length(); i++) {
            // what a hack...
            int c = "!\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~".indexOf(text.charAt(i));
            if (c == -1 || metrics[c] == null) { ret += metrics[64][4]; continue; }
            ret += metrics[c][4];
        }
        return ret;
    }

    private XWF(String name, PNG png) {
        this.name = name;
        xwtfonts.put(name, this);

        data = png.getData();
        w = png.getWidth();
        h = png.getHeight();

        intintint y1;
        boolean breakout;

        intintintintintart_y, end_x, end_y, advance;

        int[] rows = new int[120];

        int baseline = 0;

        metrics = new int[96][];
        int numglyphs = 0;

        for(y=0; y<h; y++) {

            // search for the next non-empty row
            for(breakout = false; y<h && !breakout; y++)
                for(x = 0; x<w; x++)
                    if ((data[x + y * w] & 0x00FFFFFF) != 0x00FFFFFF) breakout = true;

            start_y = y - 2;

            // search for the next empty row
            for(breakout = false; y<h && !breakout; y++)
                for(x = 0, breakout = true; x<w; x++)
                    if ((data[x + y * w] & 0x00FFFFFF) != 0x00FFFFFF) breakout = false;

            end_y = y;

            if (start_y == end_y) continue;

            for(x=0; x<w; x++) {

                // search for the next column with a non-grayscale pixel in it
                for(breakout = false; x<w && !breakout; x++)
                    for(y1 = start_y; y1<end_y; y1++)
                        if (Math.abs(((data[x + y1 * w] & 0x00FF0000) >> 16) - ((data[x + y1 * w] & 0x0000FF00) >> 8)) > 10 ||
                            Math.abs(((data[x + y1 * w] & 0x0000FF00) >> 8) - ((data[x + y1 * w] & 0x000000FF))) > 10) {
                            breakout = true;
                            baseline = y1;
                        }
                
                // search for the next column without a non-grayscale pixel in it
                for(breakout = false; x<w && !breakout; x++)
                    for(y1 = start_y, breakout = true; y1<end_y; y1++)
                        if (Math.abs(((data[x + y1 * w] & 0x00FF0000) >> 16) - ((data[x + y1 * w] & 0x0000FF00) >> 8)) > 10 ||
                            Math.abs(((data[x + y1 * w] & 0x0000FF00) >> 8) - ((data[x + y1 * w] & 0x000000FF))) > 10) {
                            breakout = false;
                        }

                x--;
                start_x = x;

                // search for the next column with a non-grayscale pixel in it
                for(breakout = false; x<w && !breakout; x++)
                    for(y1 = start_y; y1<end_y; y1++)
                        if (Math.abs(((data[x + y1 * w] & 0x00FF0000) >> 16) - ((data[x + y1 * w] & 0x0000FF00) >> 8)) > 10 ||
                            Math.abs(((data[x + y1 * w] & 0x0000FF00) >> 8) - ((data[x + y1 * w] & 0x000000FF))) > 10) {
                            breakout = true;
                            baseline = y1;
                        }
                
                x--;
                advance = x - start_x;

                // search for the next column without a grayscale pixel in it
                for(breakout = false; x<w && !breakout; x++)
                    for(y1 = start_y, breakout = true; y1<end_y; y1++)
                        if (Math.abs(((data[x + y1 * w] & 0x00FF0000) >> 16) - ((data[x + y1 * w] & 0x0000FF00) >> 8)) > 10 ||
                            Math.abs(((data[x + y1 * w] & 0x0000FF00) >> 8) - ((data[x + y1 * w] & 0x000000FF))) > 10) {
                            breakout = false;
                        }

                x--;
                end_x = x;

                if (start_x == end_x) break;

                metrics[numglyphs] = new int[6];
                metrics[numglyphs][0] = start_x;
                metrics[numglyphs][1] = end_x;
                metrics[numglyphs][2] = start_y;
                metrics[numglyphs][3] = end_y;
                metrics[numglyphs][4] = advance;
                metrics[numglyphs][5] = baseline;
                numglyphs++;

                if (numglyphs >= metrics.length) break;

            }

            if (numglyphs >= metrics.length) break;
        }

        for(int i=0; i<data.length; i++)
            if (Math.abs(((data[i] & 0x00FF0000) >> 16) - ((data[i] & 0x0000FF00) >> 8)) > 10 ||
                Math.abs(((data[i] & 0x0000FF00) >> 8) - ((data[i] & 0x000000FF))) > 10)
                data[i] = 0x00;
            else
                data[i] = (0xFF - (data[i] & 0xFF)) << 24;

        for(int i=33; i<=126; i++)
            if (metrics[i - 33] != null)
                maxascent = Math.max(maxascent, metrics[i - 33][5] - metrics[i - 33][2]);

        for(int i=33; i<=126; i++)
            if (metrics[i - 33] != null)
                maxdescent = Math.max(maxdescent, metrics[i - 33][3] - metrics[i - 33][5]);
       
    }

}