///
///     @file bdf2c.c           @brief BDF Font to C source convertor
///
///     Copyright (c) 2009, 2010 by Lutz Sammer.  All Rights Reserved.
///
///     Contributor(s):
///
///     License: AGPLv3
///
///     This program is free software: you can redistribute it and/or modify
///     it under the terms of the GNU Affero General Public License as
///     published by the Free Software Foundation, either version 3 of the
///     License.
///
///     This program is distributed in the hope that it will be useful,
///     but WITHOUT ANY WARRANTY; without even the implied warranty of
///     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
///     GNU Affero General Public License for more details.
///
///     $Id$
//////////////////////////////////////////////////////////////////////////////

///
///     @mainpage
///             bdf2c - converts bdf font files into C include files.
///
///             The Bitmap Distribution Format (BDF) is a file format for
///             storing bitmap fonts. The content is presented as a text file
///             that is intended to be human and computer readable.
///
///     BDF input:
///     @code
///     STARTCHAR A
///     ENCODING 65
///     SWIDTH 568 0
///     DWIDTH 8 0
///     BBX 8 13 0 -2
///     BITMAP
///     00
///     38
///     7C
///     C6
///     C6
///     C6
///     FE
///     C6
///     C6
///     C6
///     C6
///     00
///     00
///     ENDCHAR
///     @endcode
///
///     The result looks like this:
///     @code
///     //  65 $41 'A'
///     //      width 8, bbx 0, bby -2, bbw 8, bbh 13
///         ________,
///         __XXX___,
///         _XXXXX__,
///         XX___XX_,
///         XX___XX_,
///         XX___XX_,
///         XXXXXXX_,
///         XX___XX_,
///         XX___XX_,
///         XX___XX_,
///         XX___XX_,
///         ________,
///         ________,
///     @endcode
///

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <limits.h>
#include <errno.h>

#define VERSION "4"                     ///< version of this application

//////////////////////////////////////////////////////////////////////////////

int Outline;                            ///< true generate outlined font
int SmartMatrix;            // modify output to be used in the SmartMatrix library

//////////////////////////////////////////////////////////////////////////////

///
///     Create our header file.
///
///     @param out      file stream for output
///
void CreateFontHeaderFile(FILE * out)
{
    register int i;

    fprintf(out,
        "// (c) 2009, 2010 Lutz Sammer, License: AGPLv3\n\n"
        "\t/// bitmap font structure\n" "struct bitmap_font {\n"
        "\tunsigned char Width;\t\t///< max. character width\n"
        "\tunsigned char Height;\t\t///< character height\n"
        "\tunsigned short Chars;\t\t///< number of characters in font\n"
        "\tconst unsigned char *Widths;\t///< width of each character\n"
        "\tconst unsigned short *Index;\t///< encoding to character index\n"
        "\tconst unsigned char *Bitmap;\t///< bitmap of all characters\n"
        "};\n\n");

    fprintf(out, "\t/// @{ defines to have human readable font files\n");
    for (i = 0; i < 256; ++i) {
        fprintf(out, "#define %c%c%c%c%c%c%c%c 0x%02X\n",
            (i & 0x80) ? 'X' : '_', (i & 0x40) ? 'X' : '_',
            (i & 0x20) ? 'X' : '_', (i & 0x10) ? 'X' : '_',
            (i & 0x08) ? 'X' : '_', (i & 0x04) ? 'X' : '_',
            (i & 0x02) ? 'X' : '_', (i & 0x01) ? 'X' : '_', i);
    }
    fprintf(out, "\t/// @}\n");
}

//////////////////////////////////////////////////////////////////////////////

///
///     Print header for c file.
///
///     @param out      file stream for output
///     @param name     font variable name in C source file
///
void Header(FILE * out, const char *name)
{
    char * headername;
    if(!SmartMatrix)
        headername = "font";
    else
        headername = "MatrixFontCommon";

    fprintf(out,
        "// Created from bdf2c Version %s, (c) 2009, 2010 by Lutz Sammer\n"
        "//\tLicense AGPLv3: GNU Affero General Public License version 3\n"
        "\n#include \"%s.h\"\n\n", VERSION, headername);

    fprintf(out,
        "\t/// character bitmap for each encoding\n"
        "static const unsigned char __%s_bitmap__[] = {\n", name);
}

///
///     Print width table for c file
///
///     @param out              file stream for output
///     @param name             font variable name in C source file
///     @param width_table      width table read from BDF file
///     @param chars            number of characters in width table
///
void WidthTable(FILE * out, const char *name, const unsigned *width_table,
    int chars)
{
    fprintf(out, "};\n\n");

    fprintf(out,
        "\t/// character width for each encoding\n"
        "static const unsigned char __%s_widths__[] = {\n", name);
    while (chars--) {
        fprintf(out, "\t%u,\n", *width_table++);
    }
}

///
///     Print encoding table for c file
///
///     @param out              file stream for output
///     @param name             font variable name in C source file
///     @param encoding_table   encoding table read from BDF file
///     @param chars            number of characters in encoding table
///
void EncodingTable(FILE * out, const char *name,
    const unsigned *encoding_table, int chars)
{
    fprintf(out, "};\n\n");

    fprintf(out,
        "\t/// character encoding for each index entry\n"
        "static const unsigned short __%s_index__[] = {\n", name);
    while (chars--) {
        fprintf(out, "\t%u,\n", *encoding_table++);
    }
}

///
///     Print footer for c file.
///
///     @param out              file stream for output
///     @param name             font variable name in C source file
///     @param width            character width of font
///     @param height           character height of font
///     @param chars            number of characters in font
///
void Footer(FILE * out, const char *name, int width, int height, int chars)
{
    fprintf(out, "};\n\n");
    fprintf(out,
        "\t/// bitmap font structure\n" "const struct bitmap_font %s = {\n",
        name);
    fprintf(out, "\t.Width = %d, .Height = %d,\n", width, height);
    fprintf(out, "\t.Chars = %d,\n", chars);

    if(!SmartMatrix)
        fprintf(out, "\t.Widths = __%s_widths__,\n", name);
    else
        fprintf(out, "\t.Widths = 0,\n");

    fprintf(out, "\t.Index = __%s_index__,\n", name);
    fprintf(out, "\t.Bitmap = __%s_bitmap__,\n", name);
    fprintf(out, "};\n\n");
}

///
///     Dump character.
///
///
void DumpCharacter(FILE * out, unsigned char *bitmap, int fontwidth, int fontheight, int fontyoffset, int charheight, int charyoffset)
{
    int x;
    int y;
    int c;

    // how many rows from the top of the font bounding box is the top of this character?
    int yoffset = fontheight - charheight + (fontyoffset - charyoffset);

    for (y = 0; y < fontheight; ++y) {
        fputc('\t', out);
        for (x = 0; x < fontwidth; x += 8) {
          // if current row is above or below the bitmap, output a blank row
          if(y < yoffset || y > yoffset + charheight) {
            c = 0;
          } else {
            c = bitmap[(y - yoffset) * ((fontwidth + 7) / 8) + x / 8];

            //printf("%d = %d\n", y * ((width+7)/8) + x/8, c);
            if (c & 0x80) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            if (c & 0x40) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            if (c & 0x20) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            if (c & 0x10) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            if (c & 0x08) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            if (c & 0x04) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            if (c & 0x02) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            if (c & 0x01) {
                fputc('X', out);
            } else {
                fputc('_', out);
            }
            fputc(',', out);
          }
        }
        fputc('\n', out);
    }
}

///
///     Hex ascii to integer
///
///     @param p        hex input character (0-9a-fA-F)
///
///     @returns converted integer
///
static inline int Hex2Int(const char *p)
{
    if (*p <= '9') {
        return *p - '0';
    } else if (*p <= 'F') {
        return *p - 'A' + 10;
    } else {
        return *p - 'a' + 10;
    }
}

///
///     Rotate bitmap.
///
///     @param bitmap   input bitmap
///     @param shift    rotate counter (0-7)
///     @param width    character width
///     @param height   character height
///
void RotateBitmap(unsigned char *bitmap, int shift, int width, int height)
{
    int x;
    int y;
    int c;
    int o;

    if (shift < 0 || shift > 7) {
        fprintf(stderr, "This shift isn't supported\n");
        exit(-1);
    }

    for (y = 0; y < height; ++y) {
        o = 0;
        for (x = 0; x < width; x += 8) {
            c = bitmap[y * ((width + 7) / 8) + x / 8];
            bitmap[y * ((width + 7) / 8) + x / 8] = c >> shift | o;
            o = c << (8 - shift);
        }
    }
}

///
///     Outline character.  Create an outline font from normal fonts.
///
///     @param bitmap   input bitmap
///     @param width    character width
///     @param height   character height
///
void OutlineCharacter(unsigned char *bitmap, int width, int height)
{
    int x;
    int y;
    unsigned char *outline;

    outline = alloca(((width + 7) / 8) * height);
    memset(outline, 0, ((width + 7) / 8) * height);
    for (y = 0; y < height; ++y) {
        for (x = 0; x < width; ++x) {
            // Bit not set check surroundings
            if (~bitmap[y * ((width + 7) / 8) + x / 8] & (0x80 >> x % 8)) {
                // Upper row bit was set
                if (y
                    && bitmap[(y - 1) * ((width + 7) / 8) +
                        x / 8] & (0x80 >> x % 8)) {
                    outline[y * ((width + 7) / 8) + x / 8] |= (0x80 >> x % 8);
                    // Previous bit was set
                } else if (x
                    && bitmap[y * ((width + 7) / 8) + (x -
                        1) / 8] & (0x80 >> (x - 1) % 8)) {
                    outline[y * ((width + 7) / 8) + x / 8] |= (0x80 >> x % 8);
                    // Next bit was set
                } else if (x < width - 1
                    && bitmap[y * ((width + 7) / 8) + (x +
                        1) / 8] & (0x80 >> (x + 1) % 8)) {
                    outline[y * ((width + 7) / 8) + x / 8] |= (0x80 >> x % 8);
                    // below row was set
                } else if (y < height - 1
                    && bitmap[(y + 1) * ((width + 7) / 8) +
                        x / 8] & (0x80 >> x % 8)) {
                    outline[y * ((width + 7) / 8) + x / 8] |= (0x80 >> x % 8);
                }
            }
        }
    }
    memcpy(bitmap, outline, ((width + 7) / 8) * height);
}

///
///     Read BDF font file.
///
///     @param bdf      file stream for input (bdf file)
///     @param out      file stream for output (C source file)
///     @param name     font variable name in C source file
///
///     @todo bbx isn't used to correct character position in bitmap
///
void ReadBdf(FILE * bdf, FILE * out, const char *name)
{
    char linebuf[1024];
    char *s;
    char *p;
    int fontboundingbox_width;
    int fontboundingbox_height;
    // int fontboundingbox_xoff;
    int fontboundingbox_yoff;
    int chars;
    int i;
    int j;
    int n;
    int scanline;
    char charname[1024];
    int encoding;
    int bbx;
    int bby;
    int bbw;
    int bbh;
    int width;
    unsigned *width_table;
    unsigned *encoding_table;
    unsigned char *bitmap;

    fontboundingbox_width = 0;
    fontboundingbox_height = 0;
    // fontboundingbox_xoff = 0;
    fontboundingbox_yoff = 0;
    chars = 0;
    for (;;) {
        if (!fgets(linebuf, sizeof(linebuf), bdf)) {    // EOF
            break;
        }
        if (!(s = strtok(linebuf, " \t\n\r"))) {        // empty line
            break;
        }
        // printf("token:%s\n", s);
        if (!strcasecmp(s, "FONTBOUNDINGBOX")) {
            p = strtok(NULL, " \t\n\r");
            fontboundingbox_width = atoi(p);
            p = strtok(NULL, " \t\n\r");
            fontboundingbox_height = atoi(p);
            p = strtok(NULL, " \t\n\r");
            // fontboundingbox_xoff = atoi(p);
            p = strtok(NULL, " \t\n\r");
            fontboundingbox_yoff = atoi(p);
        } else if (!strcasecmp(s, "CHARS")) {
            p = strtok(NULL, " \t\n\r");
            chars = atoi(p);
            break;
        }
    }
    /*
       printf("%d * %dx%d\n", chars, fontboundingbox_width,
       fontboundingbox_height);
     */
    //
    //  Some checks.
    //
    if (fontboundingbox_width <= 0 || fontboundingbox_height <= 0) {
        fprintf(stderr, "Need to know the character size\n");
        exit(-1);
    }
    if (chars <= 0) {
        fprintf(stderr, "Need to know the number of characters\n");
        exit(-1);
    }
    if (Outline) {                      // Reserve space for outline border
        fontboundingbox_width++;
        fontboundingbox_height++;
    }
    //
    //  Allocate tables
    //
    width_table = malloc(chars * sizeof(*width_table));
    if (!width_table) {
        fprintf(stderr, "Out of memory\n");
        exit(-1);
    }
    encoding_table = malloc(chars * sizeof(*encoding_table));
    if (!encoding_table) {
        fprintf(stderr, "Out of memory\n");
        exit(-1);
    }
    /*  FIXME: needed for proportional fonts.
       offset_table = malloc(chars * sizeof(*offset_table));
       if (!offset_table) {
       fprintf(stderr, "Out of memory\n");
       exit(-1);
       }
     */
    bitmap =
        malloc(((fontboundingbox_width + 7) / 8) * fontboundingbox_height);
    if (!bitmap) {
        fprintf(stderr, "Out of memory\n");
        exit(-1);
    }

    Header(out, name);

    scanline = -1;
    n = 0;
    encoding = -1;
    bbx = 0;
    bby = 0;
    bbw = 0;
    bbh = 0;
    width = INT_MIN;
    strcpy(charname, "unknown character");
    for (;;) {
        if (!fgets(linebuf, sizeof(linebuf), bdf)) {    // EOF
            break;
        }
        if (!(s = strtok(linebuf, " \t\n\r"))) {        // empty line
            break;
        }
        // printf("token:%s\n", s);
        if (!strcasecmp(s, "STARTCHAR")) {
            p = strtok(NULL, " \t\n\r");
            strcpy(charname, p);
        } else if (!strcasecmp(s, "ENCODING")) {
            p = strtok(NULL, " \t\n\r");
            encoding = atoi(p);
        } else if (!strcasecmp(s, "DWIDTH")) {
            p = strtok(NULL, " \t\n\r");
            width = atoi(p);
        } else if (!strcasecmp(s, "BBX")) {
            p = strtok(NULL, " \t\n\r");
            bbw = atoi(p);
            p = strtok(NULL, " \t\n\r");
            bbh = atoi(p);
            p = strtok(NULL, " \t\n\r");
            bbx = atoi(p);
            p = strtok(NULL, " \t\n\r");
            bby = atoi(p);
        } else if (!strcasecmp(s, "BITMAP")) {
            fprintf(out, "// %3d $%02x '%s'\n", encoding, encoding, charname);
            fprintf(out, "//\twidth %d, bbx %d, bby %d, bbw %d, bbh %d\n",
                width, bbx, bby, bbw, bbh);

            if (n == chars) {
                fprintf(stderr, "Too many bitmaps for characters\n");
                exit(-1);
            }
            if (width == INT_MIN) {
                fprintf(stderr, "character width not specified\n");
                exit(-1);
            }
            //
            //  Adjust width based on bounding box
            //
            if (bbx < 0) {
                width -= bbx;
                bbx = 0;
            }
            if (bbx + bbw > width) {
                width = bbx + bbw;
            }
            if (Outline) {              // Reserve space for outline border
                ++width;
            }
            width_table[n] = width;
            encoding_table[n] = encoding;
            ++n;
            if (Outline) {              // Leave first row empty
                scanline = 1;
            } else {
                scanline = 0;
            }
            memset(bitmap, 0,
                ((fontboundingbox_width + 7) / 8) * fontboundingbox_height);
        } else if (!strcasecmp(s, "ENDCHAR")) {
            if (bbx) {
                RotateBitmap(bitmap, bbx, fontboundingbox_width,
                    fontboundingbox_height);
            }
            if (Outline) {
                RotateBitmap(bitmap, 1, fontboundingbox_width,
                    fontboundingbox_height);
                OutlineCharacter(bitmap, fontboundingbox_width,
                    fontboundingbox_height);
            }
            DumpCharacter(out, bitmap, fontboundingbox_width,
                fontboundingbox_height, fontboundingbox_yoff, bbh, bby);
            scanline = -1;
            width = INT_MIN;
        } else {
            if (scanline >= 0) {
                p = s;
                j = 0;
                while (*p) {
                    i = Hex2Int(p);
                    ++p;
                    if (*p) {
                        i = Hex2Int(p) | i * 16;
                    } else {
                        bitmap[j + scanline * ((fontboundingbox_width +
                                    7) / 8)] = i;
                        break;
                    }
                    /* printf("%d = %d\n",
                       j + scanline * ((fontboundingbox_width + 7)/8), i); */
                    bitmap[j + scanline * ((fontboundingbox_width + 7) / 8)] =
                        i;
                    ++j;
                    ++p;
                }
                ++scanline;
            }
        }
    }

    // Output width table for proportional font.
    if(!SmartMatrix)
        WidthTable(out, name, width_table, chars);
    // FIXME: Output offset table for proportional font.
    // OffsetTable(out, name, offset_table, chars);
    // Output encoding table for utf-8 support
    EncodingTable(out, name, encoding_table, chars);

    Footer(out, name, fontboundingbox_width, fontboundingbox_height, chars);
}

//////////////////////////////////////////////////////////////////////////////

///
///     Print version
///
void PrintVersion(void)
{
    printf("bdf2c Version %s, (c) 2009, 2010 by Lutz Sammer\n"
        "\tLicense AGPLv3: GNU Affero General Public License version 3\n",
        VERSION);
}

///
///     Print usage
///
void PrintUsage(void)
{
    printf("Usage: bdf2c [OPTIONs]\n"
        "\t-h or -?\tPrints this short page on stdout\n"
        "\t-b\tRead bdf file from stdin, write to stdout\n"
        "\t-c\tCreate font header on stdout\n"
        "\t-C file\tCreate font header file\n"
        "\t-n name\tName of c font variable (place it before -b)\n"
        "\t-O\tCreate outline for the font.\n");
    printf("\n\tOnly idiots print usage on stderr\n");
}

///
///     Main test program for bdf2c.
///
///
///     @param argc     number of arguments
///     @param argv     arguments vector
///
int main(int argc, char *const argv[])
{
    const char *name;

    name = "font";                      // default variable name
    //
    //  Parse arguments.
    //
    for (;;) {
        switch (getopt(argc, argv, "bcC:n:hOs?-")) {
            case 'b':                   // bdf file name
                ReadBdf(stdin, stdout, name);
                continue;
            case 'c':                   // create header file
                CreateFontHeaderFile(stdout);
                break;
            case 'C':                   // create header file
            {
                FILE *out;

                if (!(out = fopen(optarg, "w"))) {
                    fprintf(stderr, "Can't open file '%s': %s\n", optarg,
                        strerror(errno));
                    exit(-1);
                }
                CreateFontHeaderFile(out);
                fclose(out);
            }
                continue;
            case 'n':
                name = optarg;
                continue;
            case 'O':
                Outline = 1;
                continue;
        case 's':
        SmartMatrix = 1;
        continue;

            case EOF:
                break;
            case '?':
            case 'h':                   // help usage
                PrintVersion();
                PrintUsage();
                exit(0);
            case '-':
                fprintf(stderr, "We need no long options\n");
                PrintUsage();
                exit(-1);
            case ':':
                PrintVersion();
                fprintf(stderr, "Missing argument for option '%c'\n", optopt);
                exit(-1);
            default:
                PrintVersion();
                fprintf(stderr, "Unkown option '%c'\n", optopt);
                exit(-1);
        }
        break;
    }
    while (optind < argc) {
        fprintf(stderr, "Unhandled argument '%s'\n", argv[optind++]);
    }

    return 0;
}