/* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
/* hack.makemon.c - version 1.0.2 */
/* $FreeBSD: src/games/hack/hack.makemon.c,v 1.4 1999/11/16 10:26:36 marcel Exp $ */
/* $DragonFly: src/games/hack/hack.makemon.c,v 1.4 2006/08/21 19:45:32 pavalos Exp $ */

#include "hack.h"

struct monst zeromonst;

/*
 * called with [x,y] = coordinates;
 *	[0,0] means anyplace
 *	[u.ux,u.uy] means: call mnexto (if !in_mklev)
 *
 *	In case we make an Orc or killer bee, we make an entire horde (swarm);
 *	note that in this case we return only one of them (the one at [x,y]).
 */
struct monst *
makemon(struct permonst *ptr, int x, int y)
{
	struct monst *mtmp;
	int tmp, ct;
	boolean anything = (!ptr);

	if (x != 0 || y != 0)
		if (m_at(x, y))
			return (NULL);
	if (ptr) {
		if (strchr(fut_geno, ptr->mlet))
			return (NULL);
	} else {
		ct = CMNUM - strlen(fut_geno);
		if (strchr(fut_geno, 'm'))	/* make only 1 minotaur */
			ct++;
		if (strchr(fut_geno, '@'))
			ct++;
		if (ct <= 0)			/* no more monsters! */
			return (0);
		tmp = rn2(ct * dlevel / 24 + 7);
		if (tmp < dlevel - 4)
			tmp = rn2(ct * dlevel / 24 + 12);
		if (tmp >= ct)
			tmp = rn1(ct - ct / 2, ct / 2);
		for (ct = 0; ct < CMNUM; ct++) {
			ptr = &mons[ct];
			if (strchr(fut_geno, ptr->mlet))
				continue;
			if (!tmp--)
				goto gotmon;
		}
		panic("makemon?");
	}
gotmon:
	mtmp = newmonst(ptr->pxlth);
	*mtmp = zeromonst;	/* clear all entries in structure */
	for (ct = 0; (unsigned)ct < ptr->pxlth; ct++)
		((char *)&(mtmp->mextra[0]))[ct] = 0;
	mtmp->nmon = fmon;
	fmon = mtmp;
	mtmp->m_id = flags.ident++;
	mtmp->data = ptr;
	mtmp->mxlth = ptr->pxlth;
	if (ptr->mlet == 'D')
		mtmp->mhpmax = mtmp->mhp = 80;
	else if (!ptr->mlevel)
		mtmp->mhpmax = mtmp->mhp = rnd(4);
	else
		mtmp->mhpmax = mtmp->mhp = d(ptr->mlevel, 8);
	mtmp->mx = x;
	mtmp->my = y;
	mtmp->mcansee = 1;
	if (ptr->mlet == 'M') {
		mtmp->mimic = 1;
		mtmp->mappearance = ']';
	}
	if (!in_mklev) {
		if (x == u.ux && y == u.uy && ptr->mlet != ' ')
			mnexto(mtmp);
		if (x == 0 && y == 0)
			rloc(mtmp);
	}
	if (ptr->mlet == 's' || ptr->mlet == 'S') {
		mtmp->mhide = mtmp->mundetected = 1;
		if (in_mklev)
			if (mtmp->mx && mtmp->my)
				mkobj_at(0, mtmp->mx, mtmp->my);
	}
	if (ptr->mlet == ':') {
		mtmp->cham = 1;
		newcham(mtmp, &mons[dlevel + 14 + rn2(CMNUM - 14 - dlevel)]);
	}
	if (ptr->mlet == 'I' || ptr->mlet == ';')
		mtmp->minvis = 1;
	if (ptr->mlet == 'L' || ptr->mlet == 'N'
	    || (in_mklev && strchr("&w;", ptr->mlet) && rn2(5)))
		mtmp->msleep = 1;

#ifndef NOWORM
	if (ptr->mlet == 'w' && getwn(mtmp))
		initworm(mtmp);
#endif /* NOWORM */

	if (anything)
		if (ptr->mlet == 'O' || ptr->mlet == 'k') {
			coord mm;
			int cnt = rnd(10);
			mm.x = x;
			mm.y = y;
			while (cnt--) {
				mm = enexto(mm.x, mm.y);
				makemon(ptr, mm.x, mm.y);
			}
		}

	return (mtmp);
}

coord
enexto(xchar xx, xchar yy)
{
	xchar x, y;
	coord foo[15], *tfoo;
	int range;

	tfoo = foo;
	range = 1;
	do {	/* full kludge action. */
		for (x = xx - range; x <= xx + range; x++)
			if (goodpos(x, yy - range)) {
				tfoo->x = x;
				tfoo++->y = yy - range;
				if (tfoo == &foo[15])
					goto foofull;
			}
		for (x = xx - range; x <= xx + range; x++)
			if (goodpos(x, yy + range)) {
				tfoo->x = x;
				tfoo++->y = yy + range;
				if (tfoo == &foo[15])
					goto foofull;
			}
		for (y = yy + 1 - range; y < yy + range; y++)
			if (goodpos(xx - range, y)) {
				tfoo->x = xx - range;
				tfoo++->y = y;
				if (tfoo == &foo[15])
					goto foofull;
			}
		for (y = yy + 1 - range; y < yy + range; y++)
			if (goodpos(xx + range, y)) {
				tfoo->x = xx + range;
				tfoo++->y = y;
				if (tfoo == &foo[15])
					goto foofull;
			}
		range++;
	} while (tfoo == foo);
foofull:
	return (foo[rn2(tfoo - foo)]);
}

bool
goodpos(int x, int y)		/* used only in mnexto and rloc */
{
	return (
		!(x < 1 || x > COLNO - 2 || y < 1 || y > ROWNO - 2 ||
		  m_at(x, y) || !ACCESSIBLE(levl[x][y].typ)
		  || (x == u.ux && y == u.uy)
		  || sobj_at(ENORMOUS_ROCK, x, y)
		  ));
}

void
rloc(struct monst *mtmp)
{
	int tx, ty;
	char ch = mtmp->data->mlet;

#ifndef NOWORM
	if (ch == 'w' && mtmp->mx)	/* do not relocate worms */
		return;
#endif /* NOWORM */
	do {
		tx = rn1(COLNO - 3, 2);
		ty = rn2(ROWNO);
	} while (!goodpos(tx, ty));
	mtmp->mx = tx;
	mtmp->my = ty;
	if (u.ustuck == mtmp) {
		if (u.uswallow) {
			u.ux = tx;
			u.uy = ty;
			docrt();
		} else
			u.ustuck = 0;
	}
	pmon(mtmp);
}

struct monst *
mkmon_at(char let, int x, int y)
{
	int ct;
	struct permonst *ptr;

	for (ct = 0; ct < CMNUM; ct++) {
		ptr = &mons[ct];
		if (ptr->mlet == let)
			return (makemon(ptr, x, y));
	}
	return (0);
}