/*
 * lpf -- Line printer filter
 */

#include <stdio.h>
#include <sgtty.h>
#include <signal.h>

#define	LINELN	132
#define	EJLINE	63

int	anydone;
char	linebuf[LINELN+2];
int	ov;
char	ovbuf[LINELN];
FILE	*in	= {stdin};
int	lpack;
FILE	*out;
char	*ban;
int	npages	= 1;
char	chrtab[][16];
int	lineno;
struct	sgttyb ttyb =
{
	B9600,B9600,
	0, 0,
	XTABS|ANYP|CBREAK,
};
char	obuf[BUFSIZ];
int	onemt();

main(argc, argv)
char **argv;
{

	if ((out = fopen("/dev/lp", "w")) == NULL) {
		fprintf(stderr, "Can't open printer\n");
		exit(1);
	}
	setbuf(out, obuf);
	stty(fileno(out), &ttyb);
	if ((lpack = open("/dev/lp", 0)) < 0) {
		fprintf(stderr, "Can't open printer\n");
		exit(1);
	}
	signal(SIGEMT, onemt);
	if (argc > 2 && argv[1][0]=='-' && argv[1][1]=='b') {
		argc -= 2;
		banner(ban = argv[2]);
		argv += 2;
	}
	if (argc<=1) {
		anydone |= send();
		if (lineno > 0)
			feedpage();
	} else while (argc>1) {
		if ((in = fopen(argv[1], "r")) == NULL) {
			fprintf(stderr, "Can't find %s\n", argv[1]);
			argv++;
			argc--;
			anydone |= 01;
			continue;
		}
		anydone |= send();
		argc--;
		argv++;
		fclose(in);
		feedpage();
	}
	fflush(out);
	stty(fileno(out), &ttyb);
	if (anydone==0)
		exit(1);
	if (ferror(out)) {
		fprintf(out, "Printer IO error\n");
		exit(1);
	}
	fclose(out);
	if (ban && access("/usr/adm/lpacct", 02)>=0
	 && (out = fopen("/usr/adm/lpacct", "a"))!=NULL) {
		fprintf(out, "%4d %s\n", npages, ban);
	}
	return(0);
}

send()
{
	register int nskipped;

	lineno = 0;
	nskipped = 0;
	while (getline()) {
		if (lineno==0 && linebuf[0]==0 && nskipped<3) {
			nskipped ++;
			continue;
		}
		if (lineno >= EJLINE) {
			nskipped = 0;
			putline(1);
			lineno = 0;
		} else {
			putline(0);
			lineno++;
		}
	}
	if (lineno>0)
		npages++;
	return(1);
}

getline()
{
	register int col, maxcol, c;

	ov = 0;
	for (col=0; col<LINELN; col++) {
		linebuf[col] = ' ';
		ovbuf[col] = 0;
	}
	col = 0;
	maxcol = 0;
	for (;;) switch (c = getc(in)) {

	case EOF:
		return(0);

	default:
		if (c>=' ') {
			if (col < LINELN) {
				if (linebuf[col]=='_') {
					ov++;
					ovbuf[col] = '_';
				}
				linebuf[col++] = c;
				if (col > maxcol)
					maxcol = col;
			}
		}
		continue;

	case '\f':
		lineno = EJLINE;
		continue;

	case ' ':
		col++;
		continue;

	case '\t':
		col = (col|07) + 1;
		if (col>maxcol)
			maxcol = col;
		continue;

	case '\r':
		col = 0;
		continue;

	case '_':
		if (col>=LINELN) {
			col++;
			continue;
		}
		if (linebuf[col]!=' ') {
			ovbuf[col] = '_';
			ov++;
		} else
			linebuf[col] = c;
		col++;
		if (col>maxcol)
			maxcol = col;
		continue;

	case '\n':
		if (maxcol>=LINELN)
			maxcol = LINELN;
		linebuf[maxcol] = 0;
		return(1);

	case '\b':
		if (col>0)
			col--;
		continue;
	}
}

putline(ff)
{
	register char *lp, *ep;
	register int c;
	extern errno;
	int i, j;

	errno = 0;
/*
	if (ov) do {
		for (ep= &ovbuf[LINELN-1]; *ep == 0; ep--)
			continue;
		for (lp=ovbuf; lp <= ep; lp++)
			putc(*lp ? *lp : ' ', out);
	} while (ack() == 0);
*/
again:
	lp = linebuf;
	while (c = *lp++)
		putc(c, out);
	if (ff) {
		putc('\014', out);
		npages++;
	} else
		putc('\n', out);
	if (ack() == 0)
		goto again;
	if (ferror(out)) {
		printf("Printer IO error\n");
		exit(1);
	}
}

banner(s)
char *s;
{
	long timeb;
	register char *sp;
	int i, j, t;

	for (i = 0; i < 16; i++)
		do
			putc ('\n', out);
		while (ack() == 0);
	for (i=0; i<16; i++) {
		do {
			fprintf(out, "                ");
			for (sp=s; *sp; sp++) {
				if (*sp<=' '|| *sp >'}')
					continue;
				fprintf(out, "  ");
				t = chrtab[*sp - ' '][i];
				for (j=7; j>=0; j--)
					if ((t>>j) & 01)
						putc('X', out);
					else
						putc(' ', out);
			}
			putc('\n', out);
		} while (ack() == 0);
	}
	for (i = 0; i < 8; i++) {
		do
			putc ('\n', out);
		while (ack() == 0);
	}
	do {
		fprintf(out, "                ");
		fprintf(out, (time(&timeb), ctime(&timeb)));
		fprintf(out, "\n");
	} while (ack() == 0);
	do {
		fprintf(out, "\014");
	} while (ack() == 0);
}

onemt()
{

	feedpage();
	exit(0);
}

#define	ACK	06
#define	NAK	025
#define	STX	2
#define	ETX	3

nothing()
{
	;
}

ack()
{
	char	buf[256];

	int i = STX;
	write(fileno(out), &i, 1);
	putc('\r', out);
	putc(ETX, out);
	fflush(out);
	alarm(5);
	signal(SIGALRM, nothing);
	i = read(lpack, buf, 256);
	if (buf[0] == NAK)
		sleep(1);
	return (buf[0] == ACK);
}

feedpage()
{
	int retry = 0;

	fprintf(out, "\014");
	ack();
}