/*
 * fontconv converts a byte-aligned font file into a psf file.
 */

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

#include "psf.h"

PSF_header header = { PSF_MAGIC, PSF_MODE, 0 };

int isize = -1;		/* # scanlines in input charset */
int osize = -1;		/* # scanlines in output charset */
int offset = 0;		/* offset input character into output cell */
int fill = 0;		/* fill past eof with nulls instead of death */
int pad = 0;		/* prefix with null characters */

enum filetype { font=0,psf=1,ascii=2 } ;

enum filetype ifmt = font;
enum filetype ofmt = psf;

FILE *input = stdin;
FILE *output = stdout;

FILE *
openfile(char *name, char *mode)
{
    FILE *tmp;

    if (tmp = fopen(name, mode))
	return tmp;
    fprintf(stderr, "fontconv: cannot open %s (mode %s)\n", name, mode);
    exit(3);
}


enum filetype
format(char *fmt)
{
    if (strcasecmp(fmt, "font") == 0)
	return font;
    else if (strcasecmp(fmt, "psf") == 0)
	return psf;
    else if (strcasecmp(fmt, "ascii") == 0)
	return ascii;
    fprintf(stderr, "fontconv: can't handle font format %s\n", fmt);
    exit(3);
}


int
yesno(char *fmt)
{
    if (strcasecmp(fmt, "yes") == 0 || strcasecmp(fmt, "true") == 0)
	return 1;
    else if (strcasecmp(fmt, "no") == 0 || strcasecmp(fmt, "false") == 0)
	return 0;
    fprintf(stderr, "fontconv: fill must be either YES or NO\n");
    exit(3);
}


readchar(char* character, int isize, FILE* input)
{
    int x, y;
    char bfr[80];

    switch (ifmt) {
    case ascii:
	do {
	    if (fgets(bfr, 80, input) == 0)
		return 0;
	} while (bfr[0] != '%');
	x = 0;
	do {
	    if (x < isize) {
		character[x] = 0;
		for (y=0; y<8; y++)
		    if (bfr[(y+y)+2] == '@' || bfr[(y+y)+2] == '#')
			character[x] |= (1<<y);
	    }
	    x++;
	    if (fgets(bfr, 80, input) == 0)
		break;
	} while (bfr[0] == '%');
	return (x >= isize);

    default:
	return fread(character, isize, 1, input) == 1;
    }
}


writechar(char *character, int osize, FILE* output)
{
    int x, y;
    char bfr[80];

    switch (ofmt) {
    case ascii:
	    putc('\n', output);
	    for (x=0; x<osize; x++) {
		putc('%', output);
		for (y=0; y<8; y++) {
		    putc( ' ', output);
		    putc( (character[x] & (1<<y)) ? '@' : '.', output);
		}
		putc('\n', output);
		if (fflush(output) == EOF)
		    return 0;
	    }
	    return 1;

    default:
	    return fwrite(character, osize, 1, output) == 1;
    }
}

main(int argc, char **argv)
{
    char character[256];
    PSF_header ihdr;
    int i;
    char *p;

    if (argc < 3) {
	fprintf(stderr, "usage: fontconv [options] < bytefont > psf-font\n");
	exit(1);
    }

    for (i=1; i<argc; i++) {
	if (p = strchr(argv[i], '=')) {
	    *p++ = 0;
	    if (strcasecmp(argv[i], "isize") == 0)
		isize = atoi(p);
	    else if (strcasecmp(argv[i], "osize") == 0)
		osize = atoi(p);
	    else if (strcasecmp(argv[i], "pad") == 0)
		pad = atoi(p);
	    else if (strcasecmp(argv[i], "offset") == 0) {
		if (*p == '-')
		    offset = -atoi(p+1);
		else
		    offset = atoi(p);
	    }
	    else if (strcasecmp(argv[i], "if") == 0)
		input = openfile(p, "r");
	    else if (strcasecmp(argv[i], "of") == 0)
		output = openfile(p, "w");
	    else if (strcasecmp(argv[i], "source") == 0)
		ifmt = format(p);
	    else if (strcasecmp(argv[i], "dest") == 0)
		ofmt = format(p);
	    else if (strcasecmp(argv[i], "fill") == 0)
		fill = yesno(p);
	    else {
		fprintf(stderr, "fontconv: bad option %s\n", argv[i]);
		exit(1);
	    }
	}
    }
    if (ifmt == psf) {
	if (fread(&ihdr, sizeof ihdr, 1, input) != 1) {
	    perror("psf header read");
	    exit(4);
	}
	isize = ihdr.size;
    }
    if (isize < 0) {
	fprintf(stderr, "fontconv: isize not specified -- bailing out\n");
	exit(2);
    }
    if (isize > 32) {
	fprintf(stderr, "fontconv: dubious isize -- bailing out\n");
	exit(2);
    }

    if (osize < 0)
	osize = isize;
    else if (osize > 32) {
	fprintf(stderr, "fontconv: dubious osize -- bailing out\n");
	exit(2);
    }

    if (ofmt == psf) {
	header.size = osize;
	fwrite(&header, sizeof header, 1, output);
    }

    memset(character, 0, osize);
    for (i=0; i<pad; i++)
	writechar(character, osize, output);

    for (i=pad; i<256; i++) {
	memset(character, 0, 256);
	if (!readchar(character, isize, input)) {
	    if (i == 128 || fill)
		break;
	    else {
		fprintf(stderr, "unexpected eof converting character #%d\n",i);
		exit(3);
	    }
	}
	if (offset < 0) {
	    int j;
	    for (j=isize; j>-offset; --j)
		character[j] = character[j+offset];

	    for (j=0; j <= -offset; )
		character[j++] = 0;
	}
	else if (offset > 0) {
	    int j;
	    for (j=0; i<isize; j++)
		character[j] = character[j+offset];
	    for (j=isize; j<256; j++)
		character[j] = 0;
	}
	writechar(character, osize, output);
    }
    memset(character, 0, osize);
    while (i < 256) {
	writechar(character, osize, output);
	i++;
    }
    close(input);
    close(output);
    exit(0);
}