/* Copyright (c) 1986 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 *  ra_t16.c - program to convert between RADIANCE and
 *		Targa 16, 24 and 32-bit images.
 *
 *	11/2/88		Adapted from ra_t8.c
 */

#include  <stdio.h>

#include  "color.h"

#include  "targa.h"

#define  goodpic(h)	(((h)->dataType==IM_RGB || (h)->dataType==IM_CRGB) \
				&& ((h)->dataBits==16 || (h)->dataBits==24))

#define  taralloc(h)	(unsigned char *)emalloc((h)->x*(h)->y*(h)->dataBits/8)

#define  readtarga(h,d,f)	((h)->dataBits==16 ? readt16(h,d,f) : \
					readt24(h,d,f))

#define  writetarga(h,d,f)	((h)->dataBits==16 ? writet16(h,d,f) : \
					writet24(h,d,f))

extern char	*ecalloc(), *emalloc();

extern double  atof(), pow();

double	gamma = 2.0;			/* gamma correction */

char  *progname;

char  msg[128];


main(argc, argv)
int  argc;
char  *argv[];
{
	struct hdStruct  head;
	int  reverse = 0;
	int  i;
	
	progname = argv[0];

	head.dataBits = 16;
	for (i = 1; i < argc; i++)
		if (argv[i][0] == '-')
			switch (argv[i][1]) {
			case 'g':
				gamma = atof(argv[++i]);
				break;
			case 'r':
				reverse = !reverse;
				break;
			case '2':
				head.dataBits = 16;
				break;
			case '3':
				head.dataBits = 24;
				break;
			default:
				goto userr;
			}
		else
			break;

	if (i < argc-2)
		goto userr;
					/* open input file */
	if (i <= argc-1 && freopen(argv[i], "r", stdin) == NULL) {
		sprintf(msg, "can't open input \"%s\"", argv[i]);
		quiterr(msg);
	}
					/* open output file */
	if (i == argc-2 && freopen(argv[i+1], "w", stdout) == NULL) {
		sprintf(msg, "can't open output \"%s\"", argv[i+1]);
		quiterr(msg);
	}
					/* convert */
	if (reverse) {
					/* get header */
		if (getthead(&head, NULL, stdin) < 0)
			quiterr("bad targa file");
		if (!goodpic(&head))
			quiterr("incompatible format");
					/* put header */
		printargs(argc, argv, stdout);
		putchar('\n');
		printf("-Y %d +X %d\n", head.y, head.x);
					/* convert file */
		tg2ra(&head);
	} else {
		getheader(stdin, NULL);
		if (scanf("-Y %d +X %d\n", &head.y, &head.x) != 2)
			quiterr("bad picture file");
					/* assign header */
		head.textSize = 0;
		head.mapType = CM_NOMAP;
		head.dataType = IM_RGB;
		head.XOffset = 0;
		head.YOffset = 0;
		head.imType = 0;
					/* write header */
		putthead(&head, NULL, stdout);
					/* convert file */
		ra2tg(&head);
	}
	exit(0);
userr:
	fprintf(stderr, "Usage: %s [-2|-3|-r][-g gamma] [input [output]]\n",
			progname);
	exit(1);
}


int
getint2(fp)			/* get a 2-byte positive integer */
register FILE	*fp;
{
	register int  b1, b2;

	if ((b1 = getc(fp)) == EOF || (b2 = getc(fp)) == EOF)
		quiterr("read error");

	return(b1 | b2<<8);
}


putint2(i, fp)			/* put a 2-byte positive integer */
register int  i;
register FILE	*fp;
{
	putc(i&0xff, fp);
	putc(i>>8&0xff, fp);
}


quiterr(err)		/* print message and exit */
char  *err;
{
	fprintf(stderr, "%s: %s\n", progname, err);
	exit(1);
}


eputs(s)
char *s;
{
	fputs(s, stderr);
}


quit(code)
int code;
{
	exit(code);
}


getthead(hp, ip, fp)		/* read header from input */
struct hdStruct  *hp;
char  *ip;
register FILE  *fp;
{
	int	nidbytes;

	if ((nidbytes = getc(fp)) == EOF)
		return(-1);
	hp->mapType = getc(fp);
	hp->dataType = getc(fp);
	hp->mapOrig = getint2(fp);
	hp->mapLength = getint2(fp);
	hp->CMapBits = getc(fp);
	hp->XOffset = getint2(fp);
	hp->YOffset = getint2(fp);
	hp->x = getint2(fp);
	hp->y = getint2(fp);
	hp->dataBits = getc(fp);
	hp->imType = getc(fp);

	if (ip != NULL)
		if (nidbytes)
			fread(ip, nidbytes, 1, fp);
		else
			*ip = '\0';
	else if (nidbytes)
		fseek(fp, (long)nidbytes, 1);

	return(feof(fp) || ferror(fp) ? -1 : 0);
}


putthead(hp, ip, fp)		/* write header to output */
struct hdStruct  *hp;
char  *ip;
register FILE  *fp;
{
	if (ip != NULL)
		putc(strlen(ip), fp);
	else
		putc(0, fp);
	putc(hp->mapType, fp);
	putc(hp->dataType, fp);
	putint2(hp->mapOrig, fp);
	putint2(hp->mapLength, fp);
	putc(hp->CMapBits, fp);
	putint2(hp->XOffset, fp);
	putint2(hp->YOffset, fp);
	putint2(hp->x, fp);
	putint2(hp->y, fp);
	putc(hp->dataBits, fp);
	putc(hp->imType, fp);

	if (ip != NULL)
		fputs(ip, fp);

	return(ferror(fp) ? -1 : 0);
}


tg2ra(hp)			/* targa file to RADIANCE file */
struct hdStruct  *hp;
{
	float  gmap[256];
	COLOR  *scanline;
	unsigned char  *tarData;
	register int  i, j;
					/* set up gamma correction */
	for (i = 0; i < 256; i++)
		gmap[i] = pow((i+.5)/256., gamma);
					/* skip color table */
	if (hp->mapType == CM_HASMAP)
		fseek(stdin, (long)hp->mapLength*hp->CMapBits/8, 1);
					/* allocate targa data */
	tarData = taralloc(hp);
					/* get data */
	readtarga(hp, tarData, stdin);
					/* allocate input scanline */
	scanline = (COLOR *)emalloc(hp->x*sizeof(COLOR));
					/* convert file */
	for (i = hp->y-1; i >= 0; i--) {
		if (hp->dataBits == 16) {
			register unsigned short  *dp;
			dp = (unsigned short *)tarData + i*hp->x;
			for (j = 0; j < hp->x; j++) {
				setcolor(scanline[j], gmap[*dp>>7 & 0xf8],
						gmap[*dp>>2 & 0xf8],
						gmap[*dp<<3 & 0xf8]);
				dp++;
			}
		} else {	/* hp->dataBits == 24 */
			register unsigned char  *dp;
			dp = (unsigned char *)tarData + i*3*hp->x;
			for (j = 0; j < hp->x; j++) {
				setcolor(scanline[j], gmap[dp[2]],
						gmap[dp[1]],
						gmap[dp[0]]);
				dp += 3;
			}
		}
		if (fwritescan(scanline, hp->x, stdout) < 0)
			quiterr("error writing RADIANCE file");
	}
	free((char *)scanline);
	free((char *)tarData);
}


ra2tg(hp)			/* convert radiance to targa file */
struct hdStruct  *hp;
{
	unsigned char	gmap[1024];
	register int	i, j, c;
	unsigned char  *tarData;
	COLOR	*inline;
					/* set up gamma correction */
	for (i = 0; i < 1024; i++)
		gmap[i] = 256.*pow((i+.5)/1024., 1./gamma);
					/* allocate space for data */
	inline = (COLOR *)emalloc(hp->x*sizeof(COLOR));
	tarData = taralloc(hp);
					/* convert file */
	for (j = hp->y-1; j >= 0; j--) {
		if (freadscan(inline, hp->x, stdin) < 0)
			quiterr("error reading RADIANCE file");
		if (hp->dataBits == 16) {
			register unsigned short  *dp;
			dp = (unsigned short *)tarData + j*hp->x;
			for (i = 0; i < hp->x; i++) {
				c = 1024.*colval(inline[i],RED);
				if (c > 1023) c = 1023;
				*dp = (gmap[c] & 0xf8)<<7;
				c = 1024.*colval(inline[i],GRN);
				if (c > 1023) c = 1023;
				*dp |= (gmap[c] & 0xf8)<<2;
				c = 1024.*colval(inline[i],BLU);
				if (c > 1023) c = 1023;
				*dp++ |= gmap[c]>>3;
			}
		} else {	/* hp->dataBits == 24 */
			register unsigned char  *dp;
			dp = (unsigned char *)tarData + j*3*hp->x;
			for (i = 0; i < hp->x; i++) {
				c = 1024.*colval(inline[i],BLU);
				if (c > 1023) c = 1023;
				*dp++ = gmap[c];
				c = 1024.*colval(inline[i],GRN);
				if (c > 1023) c = 1023;
				*dp++ = gmap[c];
				c = 1024.*colval(inline[i],RED);
				if (c > 1023) c = 1023;
				*dp++ = gmap[c];
			}
		}
	}
						/* write out targa data */
	writetarga(hp, tarData, stdout);

	free((char *)inline);
	free((char *)tarData);
}


writet24(h, d, fp)		/* write out 24-bit targa data */
struct hdStruct  *h;
unsigned char  *d;
FILE  *fp;
{
	if (h->dataType == IM_RGB) {		/* uncompressed */
		if (fwrite(d, 3*h->x, h->y, fp) != h->y)
			quiterr("error writing targa file");
		return;
	}
	quiterr("unsupported output type");
}


writet16(h, d, fp)		/* write out 16-bit targa data */
struct hdStruct  *h;
register unsigned short  *d;
FILE  *fp;
{
	register int  cnt;

	if (h->dataType == IM_RGB) {		/* uncompressed */
		for (cnt = h->x*h->y; cnt-- > 0; )
			putint2(*d++, fp);
		if (ferror(fp))
			quiterr("error writing targa file");
		return;
	}
	quiterr("unsupported output type");
}


readt24(h, data, fp)		/* read in 24-bit targa data */
register struct hdStruct  *h;
unsigned char  *data;
FILE  *fp;
{
	register int  cnt, c;
	register unsigned char  *dp;
	int  r, g, b;

	if (h->dataType == IM_RGB) {		/* uncompressed */
		if (fread(data, 3*h->x, h->y, fp) != h->y)
			goto readerr;
		return;
	}
	for (dp = data; dp < data+3*h->x*h->y; ) {
		if ((c = getc(fp)) == EOF)
			goto readerr;
		cnt = (c & 0x7f) + 1;
		if (c & 0x80) {			/* repeated pixel */
			b = getc(fp); g = getc(fp);
			if ((r = getc(fp)) == EOF)
				goto readerr;
			while (cnt--) {
				*dp++ = b;
				*dp++ = g;
				*dp++ = r;
			}
		} else				/* non-repeating pixels */
			while (cnt--) {
				*dp++ = getc(fp); *dp++ = getc(fp);
				if ((r = getc(fp)) == EOF)
					goto readerr;
				*dp++ = r;
			}
	}
	return;
readerr:
	quiterr("error reading targa file");
}


readt16(h, data, fp)		/* read in 16-bit targa data */
register struct hdStruct  *h;
unsigned short  *data;
FILE  *fp;
{
	register int  cnt, c;
	register unsigned short  *dp;

	if (h->dataType == IM_RGB) {		/* uncompressed */
		dp = data;
		for (cnt = h->x*h->y; cnt-- > 0; )
			*dp++ = getint2(fp);
		return;
	}
	for (dp = data; dp < data+h->x*h->y; ) {
		if ((c = getc(fp)) == EOF)
			goto readerr;
		cnt = (c & 0x7f) + 1;
		if (c & 0x80) {			/* repeated pixel */
			c = getint2(fp);
			while (cnt--)
				*dp++ = c;
		} else				/* non-repeating pixels */
			while (cnt--)
				*dp++ = getint2(fp);
	}
	return;
readerr:
	quiterr("error reading targa file");
}