/*
*	dump2pic
*
*	Dump2pic converts dumpfile to picfile
*
*	usage: dump2pic [-m] dumpfile
*	option m produces monochrome output
*	picfile is written to stdout
*
*	Plan9 has similar tool named dumppic,
*	However dumppic does not read headers in dumpfile,
*	and what is worse, dumppic does not put cmap to the output.
*
*	Dump2pic read headers of dumpfile and cmap of
*	current screen, and put these informations to the output.
*
*	1998/03/20
*	Kenji Arisawa
*	E-mail: arisawa@aichi-u.ac.jp
*/

#include <u.h>
#include <libc.h>
#include <libg.h>
#include <fb.h>

/*
*	dump2pic convert dumpfile to picfile
*	reading dumpfile headers
*	putting screen-cmap
*
*	opt:
*		1 for 256 color output
*		0 for monochrome output
*/
void	dump2pic(char *input, char *output, int opt){
	PICFILE *pf;
	Bitmap *b;
	Rectangle r;
	RGB map[256]; /* see: rgbpix(2) */
	uchar cmap[256*3];
	int fd;
	int v;
	
	binit(0,0,0);
	fd = open(input,OREAD);
	if(!fd){
		fprint(2, "%s: file not open", input);
		exits(0);
	}
	b = rdbitmapfile(fd);
	if(!b){
		perror("rdbitmapfile error");
		exits(0);
	}
	close(fd);

	/* we use screen cmap */
	rdcolmap(&screen, map);
	/*
	*   Translate it to cmap
	*   Note that map[v].X is ulong (32 bits)
	*   where X is red, green and blue.
	*   see: /sys/src/fb/getmap.c
	*/
	if(opt){/* we use screen-cmap */
		for(v = 0; v < 256; v++){
			cmap[3*v + 0] = (map[255 - v].red >> 24);
			cmap[3*v + 1] = (map[255 - v].green >> 24);
			cmap[3*v + 2] = (map[255 - v].blue >> 24);
		}
	}else {/* we create monochrome cmap */
		uchar lmap[256];
		ulong x, xr, xg, xb;
		/* be careful in overflow */
		for(v=0;v < 256;v++){
			xr = map[v].red >> 16;
			xg = map[v].green >> 16;
			xb = map[v].blue >> 16;
			x = (xr*299+xg*587+xb*114)/1000;
			/* 
			*	I found these weighting parameters
			*	in /sys/src/fb/pic2gif
			*/
			lmap[v] = x >> 8;
		}
		for(v = 0; v < 256; v++){
			cmap[3*v + 0] = lmap[255 - v];
			cmap[3*v + 1] = lmap[255 - v];
			cmap[3*v + 2] = lmap[255 - v];
		}
	}

	r = b->r;
	pf=picopen_w(output, "runcode", screen.r.min.x,
		screen.r.min.y, Dx(r), Dy(r), "m", 0, (char*)cmap);
	if(pf==0){
		fprint(2,"can't create %s\n", output);
		exits("create");
	}
	if(wrpicfile(pf, b)<0){
		fprint(2, "%s: can't save\n", output);
		exits("output error");
	}
	picclose(pf);
	bfree(b);
	bclose();
}

void main(int argc, char *argv[]) {
	int opt;
	opt = 1;
	argc = getflags(argc, argv, "m:0");
	if(flag['m']) opt = 0;
	if(argc != 2) usage("dumpfile");
	dump2pic(argv[1], "OUT", opt);
}