/*	$NetBSD: snova.c,v 1.10 2018/02/08 09:05:16 dholland Exp $	*/

/*
 * Copyright (c) 1980, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 */

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)snova.c	8.1 (Berkeley) 5/31/93";
#else
__RCSID("$NetBSD: snova.c,v 1.10 2018/02/08 09:05:16 dholland Exp $");
#endif
#endif /* not lint */

#include <stdio.h>
#include <unistd.h>
#include "trek.h"

/*
**  CAUSE SUPERNOVA TO OCCUR
**
**	A supernova occurs.  If 'ix' < 0, a random quadrant is chosen;
**	otherwise, the current quadrant is taken, and (ix, iy) give
**	the sector quadrants of the star which is blowing up.
**
**	If the supernova turns out to be in the quadrant you are in,
**	you go into "emergency override mode", which tries to get you
**	out of the quadrant as fast as possible.  However, if you
**	don't have enough fuel, or if you by chance run into something,
**	or some such thing, you blow up anyway.  Oh yeh, if you are
**	within two sectors of the star, there is nothing that can
**	be done for you.
**
**	When a star has gone supernova, the quadrant becomes uninhab-
**	itable for the rest of eternity, i.e., the game.  If you ever
**	try stopping in such a quadrant, you will go into emergency
**	override mode.
*/

void
snova(int x, int y)
{
	int		qx, qy;
	int		ix, iy = 0;
	int		f;
	int		dx, dy;
	int		n;
	struct quad	*q;

	f = 0;
	ix = x;
	if (ix < 0) {
		/* choose a quadrant */
		while (1) {
			qx = ranf(NQUADS);
			qy = ranf(NQUADS);
			q = &Quad[qx][qy];
			if (q->stars > 0)
				break;
		}
		if (Ship.quadx == qx && Ship.quady == qy) {
			/* select a particular star */
			n = ranf(q->stars);
			for (ix = 0; ix < NSECTS; ix++) {
				for (iy = 0; iy < NSECTS; iy++)
					if (Sect[ix][iy] == STAR ||
					    Sect[ix][iy] == INHABIT)
						if ((n -= 1) <= 0)
							break;
				if (n <= 0)
					break;
			}
			f = 1;
		}
	} else {
		/* current quadrant */
		iy = y;
		qx = Ship.quadx;
		qy = Ship.quady;
		q = &Quad[qx][qy];
		f = 1;
	}
	if (f) {
		/* supernova is in same quadrant as Enterprise */
		printf("\a\nRED ALERT: supernova occurring at %d,%d\n", ix, iy);
		dx = ix - Ship.sectx;
		dy = iy - Ship.secty;
		if (dx * dx + dy * dy <= 2) {
			printf("***  Emergency override attem");
			sleep(1);
			printf("\n");
			lose(L_SNOVA);
		}
		q->scanned = 1000;
	} else {
		if (!damaged(SSRADIO)) {
			q->scanned = 1000;
			printf("\nUhura: Captain, Starfleet Command reports "
			       "a supernova\n");
			printf("  in quadrant %d,%d.  Caution is advised\n",
				qx, qy);
		}
	}

	/* clear out the supernova'ed quadrant */
	dx = q->klings;
	dy = q->stars;
	Now.klings -= dx;
	if (x >= 0) {
		/* Enterprise caused supernova */
		Game.kills += dy;
		if (q->bases)
			killb(qx, qy);
		Game.killk += dx;
	} else {
		if (q->bases)
			killb(qx, qy);
	}
	killd(qx, qy, (x >= 0));
	q->stars = -1;
	q->klings = 0;
	if (Now.klings <= 0) {
		printf("Lucky devil, that supernova destroyed the last "
		       "klingon\n");
		win();
	}
	return;
}