/* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
/* hack.mkmaze.c - version 1.0.2 */
/* $FreeBSD: src/games/hack/hack.mkmaze.c,v 1.4 1999/11/16 10:26:37 marcel Exp $ */
/* $DragonFly: src/games/hack/hack.mkmaze.c,v 1.3 2006/08/21 19:45:32 pavalos Exp $ */

#include "hack.h"
extern struct permonst pm_wizard;
struct permonst hell_hound =
	{ "hell hound", 'd', 12, 14, 2, 3, 6, 0 };

static void walkfrom(int, int);
static void move(int *, int *, int);
static bool okay(int, int, int);

void
makemaz(void)
{
	int x, y;
	int zx, zy;
	coord mm;
	boolean al = (dlevel >= 30 && !flags.made_amulet);

	for (x = 2; x < COLNO - 1; x++)
		for (y = 2; y < ROWNO - 1; y++)
			levl[x][y].typ = (x % 2 && y % 2) ? 0 : HWALL;
	if (al) {
		struct monst *mtmp;

		zx = 2 * (COLNO / 4) - 1;
		zy = 2 * (ROWNO / 4) - 1;
		for (x = zx - 2; x < zx + 4; x++)
			for (y = zy - 2; y <= zy + 2; y++) {
				levl[x][y].typ =
					(y == zy - 2 || y == zy + 2 || x ==
					 zx - 2 || x == zx + 3) ? POOL :
					(y == zy - 1 || y == zy + 1 || x ==
					 zx - 1 || x == zx + 2) ? HWALL :
					ROOM;
			}

		mkobj_at(AMULET_SYM, zx, zy);
		flags.made_amulet = 1;
		walkfrom(zx + 4, zy);
		if ((mtmp = makemon(&hell_hound, zx, zy)) != NULL)
			mtmp->msleep = 1;
		if ((mtmp = makemon(PM_WIZARD, zx + 1, zy)) != NULL) {
			mtmp->msleep = 1;
			flags.no_of_wizards = 1;
		}
	} else {
		mm = mazexy();
		zx = mm.x;
		zy = mm.y;
		walkfrom(zx, zy);
		mksobj_at(WAN_WISHING, zx, zy);
		mkobj_at(ROCK_SYM, zx, zy);	/* put a rock on top of it */
	}

	for (x = 2; x < COLNO - 1; x++)
		for (y = 2; y < ROWNO - 1; y++) {
			switch (levl[x][y].typ) {
			case HWALL:
				levl[x][y].scrsym = '-';
				break;
			case ROOM:
				levl[x][y].scrsym = '.';
				break;
			}
		}
	for (x = rn1(8, 11); x; x--) {
		mm = mazexy();
		mkobj_at(rn2(2) ? GEM_SYM : 0, mm.x, mm.y);
	}
	for (x = rn1(10, 2); x; x--) {
		mm = mazexy();
		mkobj_at(ROCK_SYM, mm.x, mm.y);
	}
	mm = mazexy();
	makemon(PM_MINOTAUR, mm.x, mm.y);
	for (x = rn1(5, 7); x; x--) {
		mm = mazexy();
		makemon(NULL, mm.x, mm.y);
	}
	for (x = rn1(6, 7); x; x--) {
		mm = mazexy();
		mkgold(0L, mm.x, mm.y);
	}
	for (x = rn1(6, 7); x; x--)
		mktrap(0, 1, NULL);
	mm = mazexy();
	levl[(xupstair = mm.x)][(yupstair = mm.y)].scrsym = '<';
	levl[xupstair][yupstair].typ = STAIRS;
	xdnstair = ydnstair = 0;
}

static void
walkfrom(int x, int y)
{
	int q, a, dir;
	int dirs[4];

	levl[x][y].typ = ROOM;
	for (;;) {
		q = 0;
		for (a = 0; a < 4; a++)
			if (okay(x, y, a))
				dirs[q++] = a;
		if (!q)
			return;
		dir = dirs[rn2(q)];
		move(&x, &y, dir);
		levl[x][y].typ = ROOM;
		move(&x, &y, dir);
		walkfrom(x, y);
	}
}

static void
move(int *x, int *y, int dir)
{
	switch (dir) {
	case 0:
		--(*y);
		break;
	case 1:
		(*x)++;
		break;
	case 2:
		(*y)++;
		break;
	case 3:
		--(*x);
		break;
	}
}

static bool
okay(int x, int y, int dir)
{
	move(&x, &y, dir);
	move(&x, &y, dir);
	if (x < 3 || y < 3 || x > COLNO - 3 || y > ROWNO - 3 ||
	    levl[x][y].typ != 0)
		return (0);
	else
		return (1);
}

coord
mazexy(void)
{
	coord mm;

	mm.x = 3 + 2 * rn2(COLNO / 2 - 2);
	mm.y = 3 + 2 * rn2(ROWNO / 2 - 2);
	return (mm);
}