/*
 *  utf8gif -- UTF-8エンコーディングされたテキストファイルを読んで
 *             ビットマップ→GIF変換
 *
 *	0.0: Jun. 24, 2004 by Dai ISHIJIMA (as utf8bitmap)
 *	0.1: Jul.  1, 2004 (フォント情報のキャッシュ)
 *	0.2: Jul. 24, 2004 (utf8gif)
 *	0.3: Aug. 18, 2004 (縦書き)
 *	0.4: Aug. 26, 2004 (ファイル数上限)
 *	0.5: Aug. 27, 2004 (縦書き/横書き)
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#define YES 1
#define NO  0


#define MAX_UTF8_BYTES 3

#define PPMTOGIF "/usr/local/netpbm/bin/ppmtogif"
#define CMDOPT "2>/dev/null"

#define NEWLINE '\n'

#define MAXFILES 32	/* 変換後のファイルの上限 */
#define HORZ 'h'
#define VERT 'v'

char *prog;
#define shift --argc; ++argv

#define FONTFILE "unifont.bdf"
#define OUTPUT_STDOUT "-"

#define WIDTH 128
#define HEIGHT 64

#define MAXFONT 65535
#define MAXGRYPH (8 * 1024 * 1024)

#define match(s1,s2) strncasecmp((s1), (s2), strlen(s2))

typedef struct {
    int pos;
    int width;
    int height;
} fontinfo_t;

static fontinfo_t fontinfo[MAXFONT];
static unsigned char fontbuf[MAXGRYPH];


/* BDFフォントファイルを読む */
void readbdf(char *name)
{
    FILE *fp;
    char s[BUFSIZ];
    int pos;
    int width, height;
    int code;
    int b, bytesize, j;

    pos = 0;
    if ((fp = fopen(name, "r")) == NULL) {
	fprintf(stderr, "%s: can't open %s\n", prog, name);
    }
    while (fgets(s, BUFSIZ, fp) != NULL) {
	if (match(s, "ENCODING") == 0) {	/* 文字コード */
	    if (sscanf(s, "%*s %d", &code) < 1) {
		fprintf(stderr, "%s: can't get code: %s\n", prog, s);
		code = 0;
	    }
	}
	if (match(s, "BBX") == 0) {	/* フォントサイズ */
	    if (sscanf(s, "%*s %d %d", &width, &height) < 2) {
		fprintf(stderr, "%s: can't get width and height: %s\n",
			prog, s);
		width = height = 0;
	    }
	}
	if (match(s, "BITMAP") == 0) {		/* ビットマップ */
	    fontinfo[code].pos = pos;
	    fontinfo[code].width = width;
	    fontinfo[code].height = height;
	    while (fgets(s, BUFSIZ, fp) != NULL) {
		if (match(s, "ENDFONT") == 0) {
		    break;
		}
		if (sscanf(s, "%x", &b) < 1) {
		    break;
		}
		bytesize = (width + 7) / 8;
		for (j = 0; j < bytesize; j++) {
		    if (pos + bytesize - j - 1 >= MAXGRYPH) {
			fprintf(stderr, "%s: font buffer overflow\n", prog);
			exit(1);
		    }
		    fontbuf[pos + bytesize - j - 1] = b & 0x00ff;
		    b >>= 8;
		}
		pos += bytesize;
	    }
	}
    }
    fclose(fp);
    /* キャッシュ書き出し */
    strcpy(s, name);
    strcat(s, ".cache");
    if ((fp = fopen(s, "w")) == NULL) {
	fprintf(stderr, "%s: can't open %s\n", prog, s);
    }
    fwrite(fontinfo, sizeof(fontinfo_t), MAXFONT, fp);
    fwrite(fontbuf, 1, pos, fp);
    fclose(fp);
}


/* フォント初期化 */
void initfont(char *name)
{
    char s[BUFSIZ];
    FILE *fp;

    strcpy(s, name);
    strcat(s, ".cache");
    if ((fp = fopen(s, "r")) != NULL) {
	fread(fontinfo, sizeof(fontinfo_t), MAXFONT, fp);
	fread(fontbuf, 1, MAXGRYPH, fp);
	fclose(fp);
    }
    else {
	readbdf(name);
    }
}


/* 文字コード code のフォントを返す */
char *getfont(int code, int *width, int *height)
{
    *width = fontinfo[code].width;
    *height = fontinfo[code].height;
    return(&fontbuf[fontinfo[code].pos]);
}


/* フォントのあるビットの状態 */
int bit(int width, int height, char *fontbuf, int x, int y)
{
    int pos, bit;

    pos = (x / 8) + y * ((width + 7) / 8);
    bit = 0x0080 >> (x % 8);
    return(fontbuf[pos] & bit);
}


/* ビットマップのあるビットをセット */
void bitset(int width, int height, char *bitmap, int x, int y)
{
    int pos, bit;

    pos = (x / 8) + y * ((width + 7) / 8);
    bit = 0x0080 >> (x % 8);
    bitmap[pos] |= bit;
}


/* フォントを描画 */
void putfont(int width, int height, char *canvas,
	int x, int y, char *fontbuf, int w, int h)
{
    int i, j;
    
    for (i = 0; i < h; i++) {
	for (j = 0; j < w; j++) {
	    if (bit(w, h, fontbuf, j, i)) {
		bitset(width, height, canvas, x + j, y + i);
	    }
	}
    }
}


/* UTF-8のバイト長 */
int utf8length(unsigned char ch)
{
    if (ch < 0x0080) {
	return(1);
    }
    else if (ch < 0x00e0) {
	return(2);
    }
    else {
	return(3);
    }
}


/* UTF-8文字列を16ビットUnicodeに変換 */
unsigned short utf8unicode(unsigned char *utf8)
{
    int n;
    unsigned char hi, lo, mi;
    unsigned short unicode;

    n = utf8length(*utf8);
    if (n == 1) {
	n = 1;
	unicode = *utf8;
    }
    else if (n == 2) {
	hi = *utf8 & 0x1f;
	++utf8;
	lo = *utf8 & 0x3f;
	unicode = ((unsigned short)hi << 6) + (unsigned short)lo;
    }
    else {
	hi = *utf8 & 0x0f;
	++utf8;
	mi = *utf8 & 0x3f;
	++utf8;
	lo = *utf8 & 0x3f;
	unicode
	    = ((unsigned short)hi << 12)
	    + ((unsigned short)mi << 6)
	    + (unsigned short)lo;
    }
    return(unicode);
}


/* ビットマップ領域を描画 */
void showcanvas(int width, int height, char *canvas, char *output, int no)
{
    FILE *pp;
    char cmd[BUFSIZ];

    sprintf(cmd, "%s %s > %s-%03d.gif", PPMTOGIF, CMDOPT, output, no);
    if (strcmp(output, "-") == 0) {
	pp = stdout;
    }
    else if ((pp = popen(cmd, "w")) == NULL) {
	fprintf(stderr, "%s: can't open '%s'\n", prog, cmd);
	exit(1);
    }
    fprintf(pp, "P4\n%d %d\n", width, height);
    fwrite(canvas, (width + 7) / 8, height, pp);
    if (strcmp(output, "-") != 0) {
	if (pclose(pp) < 0) {
	    fprintf(stderr, "%s: can't close '%s'\n", prog, cmd);
	}
    }
}


/* ファイルを読んでビットマップに変換 */
void utf8gif(FILE *fp,
	     int width,
	     int height,
	     char *output,
	     int linspc,
	     int maxfil,
	     int newlin,
	     int direc)
{
    int ch;
    unsigned char utf8[MAX_UTF8_BYTES];
    int x, y;
    int w, h;
    int i;
    char *canvas, *fontbuf;
    int nbytes;
    unsigned short unicode;
    int fileno;

    fileno = 0;
    x = y = 0;
    if (direc == VERT) {
	x = width;
    }
    canvas = (char *)calloc(height, (width + 7) / 8);
    bzero(canvas, height * ((width + 7) / 8));
    while ((fileno < maxfil) && ((ch = getc(fp)) != EOF)) {
	nbytes = utf8length(ch);
	utf8[0] = ch;
	for (i = 1; i < nbytes; i++) {
	    utf8[i] = getc(fp);
	}
	unicode = utf8unicode(utf8);
	fontbuf = getfont(unicode, &w, &h);
	if (direc == VERT) {			/* 縦書き */
	    if ((newlin) && (unicode == NEWLINE)) {
		y += height;
	    }
	    if (w > linspc) {
		linspc = w;
	    }
	    if (y + h > height) {
		y = 0;
		x -= linspc;
	    }
	    if (x - w < 0) {
		showcanvas(width, height, canvas, output, fileno);
		++fileno;
		y = 0;
		x = width;
		bzero(canvas, height * ((width + 7) / 8));	    
	    }
	    if (!((newlin) && (unicode == NEWLINE))) {
		putfont(width, height, canvas, x - w, y, fontbuf, w, h);
		y += h;
	    }
	}
	else {					/* 横書き */
	    if ((newlin) && (unicode == NEWLINE)) {
		x += width;
	    }
	    if (h > linspc) {
		linspc = h;
	    }
	    if (x + w > width) {
		x = 0;
		y += linspc;
	    }
	    if (y + h > height) {
		showcanvas(width, height, canvas, output, fileno);
		++fileno;
		x = y = 0;
		bzero(canvas, height * ((width + 7) / 8));	    
	    }
	    if (!((newlin) && (unicode == NEWLINE))) {
		putfont(width, height, canvas, x, y, fontbuf, w, h);
		x += w;
	    }
	}
    }
    if ((x > 0) || (y > 0)) {
	showcanvas(width, height, canvas, output, fileno);	
    }
    free(canvas);
}


void usage()
{
    fprintf(stderr, "Usage: %s [options] [file]\n", prog);
    fputs("    options:\n", stderr);
    fputs("\t-w width\n", stderr);
    fputs("\t-h height\n", stderr);
    fputs("\t-o output_basename\n", stderr);
    fputs("\t-f font\n", stderr);
}

    
int main(int argc, char *argv[])
{
    FILE *fp;
    int width, height;
    char *output;
    char *fontfile;
    int linspc;
    int maxfil;
    int newlin;
    int direc;

    width = WIDTH;
    height = HEIGHT;
    linspc = WIDTH;
    fontfile = FONTFILE;
    output = OUTPUT_STDOUT;
    maxfil = MAXFILES;
    newlin = YES;
    direc = HORZ;
    prog = *argv;
    shift;
    while ((argc > 0) && (argv[0][0] == '-')) {
	if (argv[0][1] == 'w') {
	    shift;
	    width = atoi(*argv);
	}
	else if (argv[0][1] == 'h') {
	    shift;
	    height = atoi(*argv);
	}
	else if (argv[0][1] == 'o') {
	    shift;
	    output = *argv;
	}
	else if (argv[0][1] == 'f') {
	    shift;
	    fontfile = *argv;
	}
	else if (argv[0][1] == 'l') {
	    shift;
	    linspc = atoi(*argv);
	}
	else if (argv[0][1] == 'm') {
	    shift;
	    maxfil = atoi(*argv);
	}
	else if (argv[0][1] == 'n') {
	    newlin = !newlin;
	}
	else if (argv[0][1] == 'x') {
	    direc = HORZ;
	}
	else if (argv[0][1] == 'y') {
	    direc = VERT;
	}
	else {
	    usage();
	}
	shift;
    }
    initfont(fontfile);
    if (argc > 0) {
	if ((fp = fopen(*argv, "r")) == NULL) {
	    fprintf(stderr, "%s: can't open %s\n", prog, *argv);
	    exit(1);
	}
	utf8gif(fp, width, height, output, linspc, maxfil, newlin, direc);
	fclose(fp);
    }
    else {
	utf8gif(stdin, width, height, output, linspc, maxfil, newlin, direc);
    }
    exit(0);
}

/* Local Variables: */
/* compile-command:"gcc -Wall -o utf8gif2 utf8gif2.c" */
/* End: */