/******************************************************************************
 * SAGE - Scalable Adaptive Graphics Environment
 *
 * Copyright (C) 2004 Electronic Visualization Laboratory,
 * University of Illinois at Chicago
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following disclaimer
 *    in the documentation and/or other materials provided with the distribution.
 *  * Neither the name of the University of Illinois at Chicago nor
 *    the names of its contributors may be used to endorse or promote
 *    products derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Direct questions, comments etc about SAGE to http://www.evl.uic.edu/cavern/forum/
 *
 *****************************************************************************/

/*
 * Given a Sun raster file, return an IMG containing its raster data.
 */

#include <stdio.h>
#include <stdlib.h>
#include "rasterfile.h"
#include "imginfo.h"

IMG *
rasmakedisp(filename)
    char *filename;
{
    FILE *inf;
    struct rasterfile ras;
    IMG *im = NULL;
    int xsize, ysize;
    register long *rp;
    unsigned char *rowbuf = NULL;
    long cmap[256];

    inf = fopen(filename, "r");
    if(inf == NULL) {
	fprintf(stderr, "%s: cannot open: ", filename);
	perror("");
	return NULL;
    }

    if(fread(&ras, sizeof(ras), 1, inf) <= 0 || ras.ras_magic != RAS_MAGIC)
	goto fail;

    xsize = ras.ras_width;
    ysize = ras.ras_height;

    im = (IMG *)malloc(sizeof(IMG));
    im->rowbytes = xsize * sizeof(long);
    im->type = IT_LONG;
    im->xsize = xsize;
    im->ysize = ysize;
    im->data = (unsigned char *)malloc(im->rowbytes * ysize);
    if(im->data == NULL) {
	fprintf(stderr, "Can't malloc %ld bytes of memory for image\n",
	    sizeof(long) * xsize * ysize);
	exit(2);
    }
    rp = (long *)im->data;

    switch(ras.ras_maptype) {
	unsigned char map[768];
	register int i;

    case RMT_EQUAL_RGB:
	if(ras.ras_maplength != 3*256) {
	    fprintf(stderr, "%s: can't handle colormap with %d != 256 entries",
		filename, ras.ras_maplength / 3);
	    goto fail;
	}
	if(fread(map, sizeof(map), 1, inf) <= 0) {
	    fprintf(stderr, "%s: premature EOF reading colormap", filename);
	    goto fail;
	}
	for(i = 0; i < 256; i++)
	    cmap[i] = map[i] | (map[i+256] << 8) | (map[i+512] << 16);
	break;

    case RMT_NONE:
	if(ras.ras_depth == 8) {
	    for(i = 0; i < 256; i++)
		cmap[i] = i * 0x010101;
	}
	break;

    default:
	fprintf(stderr, "%s: can't handle Sun colormap type %d\n",
		filename, ras.ras_maptype);
	goto fail;
    }

    if(ras.ras_type == RT_BYTE_ENCODED) {
	if(ras.ras_depth != 8) {
	    fprintf(stderr, "%s: can't handle byte-encoded %d-bit images\n",
		filename, ras.ras_depth);
	    goto fail;
	}
	rowbuf = (unsigned char *)malloc(ras.ras_width*sizeof(unsigned char *));
    }

    if(ras.ras_width > 0) {
	register int i, c;
	int row;

	for(row = 0; row < ras.ras_height; row++) {
	    rp = (long *)(im->data + im->rowbytes*(ysize-1 - row));
	    i = xsize;
	    switch(ras.ras_depth) {
	    case 1:
		while((c = getc(inf)) != EOF && i >= 8) {
		    *rp++ = (c&0x80) ? 0xFFFFFF : 0;
		    *rp++ = (c&0x40) ? 0xFFFFFF : 0;
		    *rp++ = (c&0x20) ? 0xFFFFFF : 0;
		    *rp++ = (c&0x10) ? 0xFFFFFF : 0;
		    *rp++ = (c&0x08) ? 0xFFFFFF : 0;
		    *rp++ = (c&0x04) ? 0xFFFFFF : 0;
		    *rp++ = (c&0x02) ? 0xFFFFFF : 0;
		    *rp++ = (c&0x01) ? 0xFFFFFF : 0;
		}
		if(c != EOF) {
		    while(--i >= 0) {
			*rp++ = (c&0x80) ? 0xFFFFFF : 0;
			c <<= 1;
		    }
		}
		break;

	    case 24:
		do {
		    c = getc(inf);
		    c |= getc(inf) << 8;
		    *rp++ = c | getc(inf) << 16;
		} while(--i > 0);
		break;

	    case 8:
		if(ras.ras_type == RT_BYTE_ENCODED) {
		    register unsigned char *rowp = rowbuf;
		    int nleft = ras.ras_width;
		    int seen = 0;

		    do {
			seen++;
			c = getc(inf);
			if(c == 128) {
			    seen++;
			    c = getc(inf);
			    if(c == 0) {
				*rowp++ = 128;
			    } else {
				seen++;
				nleft -= c;
				i = getc(inf);
				do { *rowp++ = i; } while(--c >= 0);
			    }
			} else {
			    *rowp++ = c;
			}
		    } while(--nleft > 0);
		    if(seen&1)
			(void) getc(inf);
		    /*
		     * Copy uncompressed data.
		     */
		    i = xsize;
		    rowp = rowbuf;
		    do { *rp++ = cmap[*rowp++]; } while(--i > 0);

		} else {

		    do {
			*rp++ = cmap[getc(inf)];
		    } while(--i > 0);
		}
		break;
	    }

	    if(feof(inf)) {
		fprintf(stderr, "%s: premature EOF reading row %d of %d\n",
		    filename, row, ras.ras_height);
		break;
	    }

	    if(ras.ras_type != RT_BYTE_ENCODED) {
		i = (((ras.ras_width*ras.ras_depth + 15) & ~15) >> 3) - xsize;
		while(--i >= 0)
		    (void) getc(inf);
	    }
	}
    }
    if(rowbuf != NULL)
	free(rowbuf);
    if(inf != NULL)
	fclose(inf);
    return im;

  fail:
    if(im) {
	if(im->data) free(im->data);
	free(im);
    }
    if(inf != NULL)
	fclose(inf);
    return NULL;
}