/* NetHack 3.5	detect.c	$NHDT-Date$  $NHDT-Branch$:$NHDT-Revision$ */
/* NetHack 3.5	detect.c	$Date: 2012/04/16 02:05:40 $  $Revision: 1.47 $ */
/* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
/* NetHack may be freely redistributed.  See license for details. */

/*
 * Detection routines, including crystal ball, magic mapping, and search
 * command.
 */

#include "hack.h"
#include "artifact.h"

extern boolean known;	/* from read.c */

STATIC_DCL void FDECL(do_dknown_of, (struct obj *));
STATIC_DCL boolean FDECL(check_map_spot, (int,int,CHAR_P,unsigned));
STATIC_DCL boolean FDECL(clear_stale_map, (CHAR_P,unsigned));
STATIC_DCL void FDECL(sense_trap, (struct trap *,XCHAR_P,XCHAR_P,int));
STATIC_DCL int FDECL(detect_obj_traps, (struct obj *,BOOLEAN_P,int));
STATIC_DCL void FDECL(show_map_spot, (int,int));
STATIC_PTR void FDECL(findone,(int,int,genericptr_t));
STATIC_PTR void FDECL(openone,(int,int,genericptr_t));

/* Recursively search obj for an object in class oclass and return 1st found */
struct obj *
o_in(obj, oclass)
struct obj* obj;
char oclass;
{
    register struct obj* otmp;
    struct obj *temp;

    if (obj->oclass == oclass) return obj;

    if (Has_contents(obj)) {
	for (otmp = obj->cobj; otmp; otmp = otmp->nobj)
	    if (otmp->oclass == oclass) return otmp;
	    else if (Has_contents(otmp) && (temp = o_in(otmp, oclass)))
		return temp;
    }
    return (struct obj *) 0;
}

/* Recursively search obj for an object made of specified material and return 1st found */
struct obj *
o_material(obj, material)
struct obj* obj;
unsigned material;
{
    register struct obj* otmp;
    struct obj *temp;

    if (objects[obj->otyp].oc_material == material) return obj;

    if (Has_contents(obj)) {
	for (otmp = obj->cobj; otmp; otmp = otmp->nobj)
	    if (objects[otmp->otyp].oc_material == material) return otmp;
	    else if (Has_contents(otmp) && (temp = o_material(otmp, material)))
		return temp;
    }
    return (struct obj *) 0;
}

STATIC_OVL void
do_dknown_of(obj)
struct obj *obj;
{
    struct obj *otmp;

    obj->dknown = 1;
    if (Has_contents(obj)) {
	for(otmp = obj->cobj; otmp; otmp = otmp->nobj)
	    do_dknown_of(otmp);
    }
}

/* Check whether the location has an outdated object displayed on it. */
STATIC_OVL boolean
check_map_spot(x, y, oclass, material)
int x, y;
register char oclass;
unsigned material;
{
	register int glyph;
	register struct obj *otmp;
	register struct monst *mtmp;

	glyph = glyph_at(x,y);
	if (glyph_is_object(glyph)) {
	    /* there's some object shown here */
	    if (oclass == ALL_CLASSES) {
		return((boolean)( !(level.objects[x][y] ||     /* stale if nothing here */
			    ((mtmp = m_at(x,y)) != 0 && ( mtmp->minvent)))));
	    } else {
		if (material && objects[glyph_to_obj(glyph)].oc_material == material) {
			/* the object shown here is of interest because material matches */
			for (otmp = level.objects[x][y]; otmp; otmp = otmp->nexthere)
				if (o_material(otmp, GOLD)) return FALSE;
			/* didn't find it; perhaps a monster is carrying it */
			if ((mtmp = m_at(x,y)) != 0) {
				for (otmp = mtmp->minvent; otmp; otmp = otmp->nobj)
					if (o_material(otmp, GOLD)) return FALSE;
		        }
			/* detection indicates removal of this object from the map */
			return TRUE;
		}
	        if (oclass && objects[glyph_to_obj(glyph)].oc_class == oclass) {
			/* the object shown here is of interest because its class matches */
			for (otmp = level.objects[x][y]; otmp; otmp = otmp->nexthere)
				if (o_in(otmp, oclass)) return FALSE;
			/* didn't find it; perhaps a monster is carrying it */
			if ((mtmp = m_at(x,y)) != 0) {
				for (otmp = mtmp->minvent; otmp; otmp = otmp->nobj)
					if (o_in(otmp, oclass)) return FALSE;
		        }
			/* detection indicates removal of this object from the map */
			return TRUE;
	        }
	    }
	}
	return FALSE;
}

/*
   When doing detection, remove stale data from the map display (corpses
   rotted away, objects carried away by monsters, etc) so that it won't
   reappear after the detection has completed.  Return true if noticeable
   change occurs.
 */
STATIC_OVL boolean
clear_stale_map(oclass, material)
register char oclass;
unsigned material;
{
	register int zx, zy;
	register boolean change_made = FALSE;

	for (zx = 1; zx < COLNO; zx++)
	    for (zy = 0; zy < ROWNO; zy++)
		if (check_map_spot(zx, zy, oclass,material)) {
		    unmap_object(zx, zy);
		    change_made = TRUE;
		}

	return change_made;
}

/* look for gold, on the floor or in monsters' possession */
int
gold_detect(sobj)
register struct obj *sobj;
{
    register struct obj *obj;
    register struct monst *mtmp;
    struct obj *temp;
    boolean stale;

    known = stale = clear_stale_map(COIN_CLASS,
				(unsigned)(sobj->blessed ? GOLD : 0));

    /* look for gold carried by monsters (might be in a container) */
    for (mtmp = fmon; mtmp; mtmp = mtmp->nmon) {
    	if (DEADMONSTER(mtmp)) continue;	/* probably not needed in this case but... */
	if (findgold(mtmp->minvent) || monsndx(mtmp->data) == PM_GOLD_GOLEM) {
	    known = TRUE;
	    goto outgoldmap;	/* skip further searching */
	} else for (obj = mtmp->minvent; obj; obj = obj->nobj)
	    if (sobj->blessed && o_material(obj, GOLD)) {
	    	known = TRUE;
	    	goto outgoldmap;
	    } else if (o_in(obj, COIN_CLASS)) {
		known = TRUE;
		goto outgoldmap;	/* skip further searching */
	    }
    }
    
    /* look for gold objects */
    for (obj = fobj; obj; obj = obj->nobj) {
	if (sobj->blessed && o_material(obj, GOLD)) {
	    known = TRUE;
	    if (obj->ox != u.ux || obj->oy != u.uy) goto outgoldmap;
	} else if (o_in(obj, COIN_CLASS)) {
	    known = TRUE;
	    if (obj->ox != u.ux || obj->oy != u.uy) goto outgoldmap;
	}
    }

    if (!known) {
	/* no gold found on floor or monster's inventory.
	   adjust message if you have gold in your inventory */
	if (sobj) {
		char buf[BUFSZ];
		if (youmonst.data == &mons[PM_GOLD_GOLEM]) {
			Sprintf(buf, "You feel like a million %s!",
				currency(2L));
		} else if (hidden_gold() || money_cnt(invent))
			Strcpy(buf,
				"You feel worried about your future financial situation.");
		else
			Strcpy(buf, "You feel materially poor.");
		strange_feeling(sobj, buf);
        }
	return(1);
    }
    /* only under me - no separate display required */
    if (stale) docrt();
    You("notice some gold between your %s.", makeplural(body_part(FOOT)));
    return(0);

outgoldmap:
    cls();

    iflags.save_uinwater = u.uinwater, iflags.save_uburied = u.uburied;
    u.uinwater = u.uburied = 0;
    /* Discover gold locations. */
    for (obj = fobj; obj; obj = obj->nobj) {
    	if (sobj->blessed && (temp = o_material(obj, GOLD))) {
	    if (temp != obj) {
		temp->ox = obj->ox;
		temp->oy = obj->oy;
	    }
	    map_object(temp,1);
	} else if ((temp = o_in(obj, COIN_CLASS))) {
	    if (temp != obj) {
		temp->ox = obj->ox;
		temp->oy = obj->oy;
	    }
	    map_object(temp,1);
	}
    }
    for (mtmp = fmon; mtmp; mtmp = mtmp->nmon) {
    	if (DEADMONSTER(mtmp)) continue;	/* probably overkill here */
	if (findgold(mtmp->minvent) || monsndx(mtmp->data) == PM_GOLD_GOLEM) {
	    struct obj gold;
	    gold = zeroobj;		/* ensure oextra is cleared too */
	    gold.otyp = GOLD_PIECE;
	    gold.ox = mtmp->mx;
	    gold.oy = mtmp->my;
	    map_object(&gold,1);
	} else for (obj = mtmp->minvent; obj; obj = obj->nobj)
	    if (sobj->blessed && (temp = o_material(obj, GOLD))) {
		temp->ox = mtmp->mx;
		temp->oy = mtmp->my;
		map_object(temp,1);
		break;
	    } else if ((temp = o_in(obj, COIN_CLASS))) {
		temp->ox = mtmp->mx;
		temp->oy = mtmp->my;
		map_object(temp,1);
		break;
	    }
    }
    newsym(u.ux,u.uy);
    u.uinwater = iflags.save_uinwater, u.uburied = iflags.save_uburied;
    You_feel("very greedy, and sense gold!");
    exercise(A_WIS, TRUE);
    display_nhwindow(WIN_MAP, TRUE);
    docrt();
    if (Underwater) under_water(2);
    if (u.uburied) under_ground(2);
    return(0);
}

/* returns 1 if nothing was detected		*/
/* returns 0 if something was detected		*/
int
food_detect(sobj)
register struct obj	*sobj;
{
    register struct obj *obj;
    register struct monst *mtmp;
    register int ct = 0, ctu = 0;
    boolean confused = (Confusion || (sobj && sobj->cursed)), stale;
    char oclass = confused ? POTION_CLASS : FOOD_CLASS;
    const char *what = confused ? something : "food";

    stale = clear_stale_map(oclass, 0);

    for (obj = fobj; obj; obj = obj->nobj)
	if (o_in(obj, oclass)) {
	    if (obj->ox == u.ux && obj->oy == u.uy) ctu++;
	    else ct++;
	}
    for (mtmp = fmon; mtmp && !ct; mtmp = mtmp->nmon) {
	/* no DEADMONSTER(mtmp) check needed since dmons never have inventory */
	for (obj = mtmp->minvent; obj; obj = obj->nobj)
	    if (o_in(obj, oclass)) {
		ct++;
		break;
	    }
    }
    
    if (!ct && !ctu) {
	known = stale && !confused;
	if (stale) {
	    docrt();
	    You("sense a lack of %s nearby.", what);
	    if (sobj && sobj->blessed) {
		if (!u.uedibility) Your("%s starts to tingle.", body_part(NOSE));
		u.uedibility = 1;
	    }
	} else if (sobj) {
	    char buf[BUFSZ];
	    Sprintf(buf, "Your %s twitches%s.", body_part(NOSE),
			(sobj->blessed && !u.uedibility) ? " then starts to tingle" : "");
	    if (sobj->blessed && !u.uedibility) {
		boolean savebeginner = flags.beginner;	/* prevent non-delivery of */
		flags.beginner = FALSE;			/* 	message            */
		strange_feeling(sobj, buf);
		flags.beginner = savebeginner;
		u.uedibility = 1;
	    } else
		strange_feeling(sobj, buf);
	}
	return !stale;
    } else if (!ct) {
	known = TRUE;
	You("%s %s nearby.", sobj ? "smell" : "sense", what);
	if (sobj && sobj->blessed) {
		if (!u.uedibility) pline("Your %s starts to tingle.", body_part(NOSE));
		u.uedibility = 1;
	}
    } else {
	struct obj *temp;
	known = TRUE;
	cls();
	iflags.save_uinwater = u.uinwater, iflags.save_uburied = u.uburied;
	u.uinwater = u.uburied = 0;
	for (obj = fobj; obj; obj = obj->nobj)
	    if ((temp = o_in(obj, oclass)) != 0) {
		if (temp != obj) {
		    temp->ox = obj->ox;
		    temp->oy = obj->oy;
		}
		map_object(temp,1);
	    }
	for (mtmp = fmon; mtmp; mtmp = mtmp->nmon)
	    /* no DEADMONSTER(mtmp) check needed since dmons never have inventory */
	    for (obj = mtmp->minvent; obj; obj = obj->nobj)
		if ((temp = o_in(obj, oclass)) != 0) {
		    temp->ox = mtmp->mx;
		    temp->oy = mtmp->my;
		    map_object(temp,1);
		    break;	/* skip rest of this monster's inventory */
		}
	newsym(u.ux,u.uy);
	u.uinwater = iflags.save_uinwater, u.uburied = iflags.save_uburied;
	if (sobj) {
	    if (sobj->blessed) {
		Your("%s %s to tingle and you smell %s.", body_part(NOSE),
		     u.uedibility ? "continues" : "starts", what);
		u.uedibility = 1;
	    } else
		Your("%s tingles and you smell %s.", body_part(NOSE), what);
	} else
	    You("sense %s.", what);
	display_nhwindow(WIN_MAP, TRUE);
	exercise(A_WIS, TRUE);
	docrt();
	if (Underwater) under_water(2);
	if (u.uburied) under_ground(2);
    }
    return(0);
}

/*
 * Used for scrolls, potions, spells, and crystal balls.  Returns:
 *
 *	1 - nothing was detected
 *	0 - something was detected
 */
int
object_detect(detector, class)
struct obj	*detector;	/* object doing the detecting */
int		class;		/* an object class, 0 for all */
{
    register int x, y;
    char stuff[BUFSZ];
    int is_cursed = (detector && detector->cursed);
    int do_dknown = (detector && (detector->oclass == POTION_CLASS ||
				    detector->oclass == SPBOOK_CLASS) &&
			detector->blessed);
    int ct = 0, ctu = 0;
    register struct obj *obj, *otmp = (struct obj *)0;
    register struct monst *mtmp;
    int sym, boulder = 0;

    if (class < 0 || class >= MAXOCLASSES) {
	impossible("object_detect:  illegal class %d", class);
	class = 0;
    }

    /* Special boulder symbol check - does the class symbol happen
     * to match iflags.bouldersym which is a user-defined?
     * If so, that means we aren't sure what they really wanted to
     * detect. Rather than trump anything, show both possibilities.
     * We can exclude checking the buried obj chain for boulders below.
     */
    sym = class ? def_oc_syms[class].sym : 0;
    if (sym && iflags.bouldersym && sym == iflags.bouldersym)
    	boulder = ROCK_CLASS;

    if (Hallucination || (Confusion && class == SCROLL_CLASS))
	Strcpy(stuff, something);
    else
    	Strcpy(stuff, class ? def_oc_syms[class].name : "objects");
    if (boulder && class != ROCK_CLASS) Strcat(stuff, " and/or large stones");

    if (do_dknown) for(obj = invent; obj; obj = obj->nobj) do_dknown_of(obj);

    for (obj = fobj; obj; obj = obj->nobj) {
	if ((!class && !boulder) || o_in(obj, class) || o_in(obj, boulder)) {
	    if (obj->ox == u.ux && obj->oy == u.uy) ctu++;
	    else ct++;
	}
	if (do_dknown) do_dknown_of(obj);
    }

    for (obj = level.buriedobjlist; obj; obj = obj->nobj) {
	if (!class || o_in(obj, class)) {
	    if (obj->ox == u.ux && obj->oy == u.uy) ctu++;
	    else ct++;
	}
	if (do_dknown) do_dknown_of(obj);
    }

    for (mtmp = fmon; mtmp; mtmp = mtmp->nmon) {
	if (DEADMONSTER(mtmp)) continue;
	for (obj = mtmp->minvent; obj; obj = obj->nobj) {
	    if ((!class && !boulder) || o_in(obj, class) || o_in(obj, boulder)) ct++;
	    if (do_dknown) do_dknown_of(obj);
	}
	if ((is_cursed && mtmp->m_ap_type == M_AP_OBJECT &&
	    (!class || class == objects[mtmp->mappearance].oc_class)) ||
	    (findgold(mtmp->minvent) && (!class || class == COIN_CLASS))) {
	    ct++;
	    break;
	}
    }

    if (!clear_stale_map(!class ? ALL_CLASSES : class, 0) && !ct) {
	if (!ctu) {
	    if (detector)
		strange_feeling(detector, "You feel a lack of something.");
	    return 1;
	}

	You("sense %s nearby.", stuff);
	return 0;
    }

    cls();

    iflags.save_uinwater = u.uinwater, iflags.save_uburied = u.uburied;
    u.uinwater = u.uburied = 0;
/*
 *	Map all buried objects first.
 */
    for (obj = level.buriedobjlist; obj; obj = obj->nobj)
	if (!class || (otmp = o_in(obj, class))) {
	    if (class) {
		if (otmp != obj) {
		    otmp->ox = obj->ox;
		    otmp->oy = obj->oy;
		}
		map_object(otmp, 1);
	    } else
		map_object(obj, 1);
	}
    /*
     * If we are mapping all objects, map only the top object of a pile or
     * the first object in a monster's inventory.  Otherwise, go looking
     * for a matching object class and display the first one encountered
     * at each location.
     *
     * Objects on the floor override buried objects.
     */
    for (x = 1; x < COLNO; x++)
	for (y = 0; y < ROWNO; y++)
	    for (obj = level.objects[x][y]; obj; obj = obj->nexthere)
		if ((!class && !boulder) ||
		    (otmp = o_in(obj, class)) || (otmp = o_in(obj, boulder))) {
		    if (class || boulder) {
			if (otmp != obj) {
			    otmp->ox = obj->ox;
			    otmp->oy = obj->oy;
			}
			map_object(otmp, 1);
		    } else
			map_object(obj, 1);
		    break;
		}

    /* Objects in the monster's inventory override floor objects. */
    for (mtmp = fmon ; mtmp ; mtmp = mtmp->nmon) {
	if (DEADMONSTER(mtmp)) continue;
	for (obj = mtmp->minvent; obj; obj = obj->nobj)
	    if ((!class && !boulder) ||
		 (otmp = o_in(obj, class)) || (otmp = o_in(obj, boulder))) {
		if (!class && !boulder) otmp = obj;
		otmp->ox = mtmp->mx;		/* at monster location */
		otmp->oy = mtmp->my;
		map_object(otmp, 1);
		break;
	    }
	/* Allow a mimic to override the detected objects it is carrying. */
	if (is_cursed && mtmp->m_ap_type == M_AP_OBJECT &&
		(!class || class == objects[mtmp->mappearance].oc_class)) {
	    struct obj temp;

	    temp.oextra = (struct oextra *)0;
	    temp.otyp = mtmp->mappearance;	/* needed for obj_to_glyph() */
	    temp.ox = mtmp->mx;
	    temp.oy = mtmp->my;
	    temp.corpsenm = PM_TENGU;		/* if mimicing a corpse */
	    map_object(&temp, 1);
	} else if (findgold(mtmp->minvent) && (!class || class == COIN_CLASS)) {
	    struct obj gold;
	    gold = zeroobj;		/* ensure oextra is cleared too */
	    gold.otyp = GOLD_PIECE;
	    gold.ox = mtmp->mx;
	    gold.oy = mtmp->my;
	    map_object(&gold, 1);
	}
    }

    newsym(u.ux,u.uy);
    u.uinwater = iflags.save_uinwater, u.uburied = iflags.save_uburied;
    You("detect the %s of %s.", ct ? "presence" : "absence", stuff);
    display_nhwindow(WIN_MAP, TRUE);
    /*
     * What are we going to do when the hero does an object detect while blind
     * and the detected object covers a known pool?
     */
    docrt();	/* this will correctly reset vision */

    if (Underwater) under_water(2);
    if (u.uburied) under_ground(2);
    return 0;
}

/*
 * Used by: crystal balls, potions, fountains
 *
 * Returns 1 if nothing was detected.
 * Returns 0 if something was detected.
 */
int
monster_detect(otmp, mclass)
register struct obj *otmp;	/* detecting object (if any) */
int mclass;			/* monster class, 0 for all */
{
    register struct monst *mtmp;
    int mcnt = 0;


    /* Note: This used to just check fmon for a non-zero value
     * but in versions since 3.3.0 fmon can test TRUE due to the
     * presence of dmons, so we have to find at least one
     * with positive hit-points to know for sure.
     */
    for (mtmp = fmon; mtmp; mtmp = mtmp->nmon)
    	if (!DEADMONSTER(mtmp)) {
		mcnt++;
		break;
	}

    if (!mcnt) {
	if (otmp)
	    strange_feeling(otmp, Hallucination ?
			    "You get the heebie jeebies." :
			    "You feel threatened.");
	return 1;
    } else {
	boolean woken = FALSE;

	cls();
	for (mtmp = fmon; mtmp; mtmp = mtmp->nmon) {
	    if (DEADMONSTER(mtmp)) continue;
	    if (!mclass || mtmp->data->mlet == mclass ||
		(mtmp->data == &mons[PM_LONG_WORM] && mclass == S_WORM_TAIL))
		    if (mtmp->mx > 0) {
		    	if (mclass && def_monsyms[mclass].sym == ' ')
				show_glyph(mtmp->mx,mtmp->my,
					detected_mon_to_glyph(mtmp));
			else
				show_glyph(mtmp->mx,mtmp->my,mon_to_glyph(mtmp));
			/* don't be stingy - display entire worm */
			if (mtmp->data == &mons[PM_LONG_WORM]) detect_wsegs(mtmp,0);
		    }
	    if (otmp && otmp->cursed &&
		(mtmp->msleeping || !mtmp->mcanmove)) {
		mtmp->msleeping = mtmp->mfrozen = 0;
		mtmp->mcanmove = 1;
		woken = TRUE;
	    }
	}
	display_self();
	You("sense the presence of monsters.");
	if (woken)
	    pline("Monsters sense the presence of you.");
	display_nhwindow(WIN_MAP, TRUE);
	docrt();
	if (Underwater) under_water(2);
	if (u.uburied) under_ground(2);
    }
    return 0;
}

STATIC_OVL void
sense_trap(trap, x, y, src_cursed)
struct trap *trap;
xchar x, y;
int src_cursed;
{
    if (Hallucination || src_cursed) {
	struct obj obj;		/* fake object */

	obj.oextra = (struct oextra *)0;
	if (trap) {
	    obj.ox = trap->tx;
	    obj.oy = trap->ty;
	} else {
	    obj.ox = x;
	    obj.oy = y;
	}
	obj.otyp = (src_cursed) ? GOLD_PIECE : random_object();
	obj.corpsenm = random_monster();	/* if otyp == CORPSE */
	map_object(&obj,1);
    } else if (trap) {
	map_trap(trap,1);
	trap->tseen = 1;
    } else {
	struct trap temp_trap;		/* fake trap */
	temp_trap.tx = x;
	temp_trap.ty = y;
	temp_trap.ttyp = BEAR_TRAP;	/* some kind of trap */
	map_trap(&temp_trap,1);
    }

}

#define OTRAP_NONE	0	/* nothing found */
#define OTRAP_HERE	1	/* found at hero's location */
#define OTRAP_THERE	2	/* found at any other location */

/* check a list of objects for chest traps; return 1 if found at <ux,uy>,
   2 if found at some other spot, 3 if both, 0 otherwise; optionally
   update the map to show where such traps were found */
STATIC_OVL int
detect_obj_traps(objlist, show_them, how)
struct obj *objlist;
boolean show_them;
int how;		/* 1 for misleading map feedback */
{
    struct obj *otmp;
    xchar x, y;
    int result = OTRAP_NONE;

    for (otmp = objlist; otmp; otmp = otmp->nobj) {
	if (Is_box(otmp) && otmp->otrapped &&
		get_obj_location(otmp, &x, &y, BURIED_TOO|CONTAINED_TOO)) {
	    result |= (x == u.ux && y == u.uy) ? OTRAP_HERE : OTRAP_THERE;
	    if (show_them) sense_trap((struct trap *)0, x, y, how);
	}
	if (Has_contents(otmp))
	    result |= detect_obj_traps(otmp->cobj, show_them, how);
    }
    return result;
}

/* the detections are pulled out so they can	*/
/* also be used in the crystal ball routine	*/
/* returns 1 if nothing was detected		*/
/* returns 0 if something was detected		*/
int
trap_detect(sobj)
register struct obj *sobj;
/* sobj is null if crystal ball, *scroll if gold detection scroll */
{
    register struct trap *ttmp;
    struct monst *mon;
    int door, glyph, tr;
    int cursed_src = sobj && sobj->cursed;
    boolean found = FALSE;
    coord cc;

    /* floor/ceiling traps */
    for (ttmp = ftrap; ttmp; ttmp = ttmp->ntrap) {
	if (ttmp->tx != u.ux || ttmp->ty != u.uy)
	    goto outtrapmap;
	else found = TRUE;
    }
    /* chest traps (might be buried or carried) */
    if ((tr = detect_obj_traps(fobj, FALSE, 0)) != OTRAP_NONE) {
	if (tr & OTRAP_THERE) goto outtrapmap;
	else found = TRUE;
    }
    if ((tr = detect_obj_traps(level.buriedobjlist, FALSE, 0)) != OTRAP_NONE) {
	if (tr & OTRAP_THERE) goto outtrapmap;
	else found = TRUE;
    }
    for (mon = fmon; mon; mon = mon->nmon) {
	if (DEADMONSTER(mon)) continue;
	if ((tr = detect_obj_traps(mon->minvent, FALSE, 0)) != OTRAP_NONE) {
	    if (tr & OTRAP_THERE) goto outtrapmap;
	    else found = TRUE;
	}
    }
    if (detect_obj_traps(invent, FALSE, 0) != OTRAP_NONE)
	found = TRUE;
    /* door traps */
    for (door = 0; door < doorindex; door++) {
	cc = doors[door];
	if (levl[cc.x][cc.y].doormask & D_TRAPPED) {
	    if (cc.x != u.ux || cc.y != u.uy)
		goto outtrapmap;
	    else found = TRUE;
	}
    }
    if (!found) {
	char buf[BUFSZ];

	Sprintf(buf, "Your %s stop itching.", makeplural(body_part(TOE)));
	strange_feeling(sobj,buf);
	return(1);
    }
    /* traps exist, but only under me - no separate display required */
    Your("%s itch.", makeplural(body_part(TOE)));
    return(0);
outtrapmap:
    cls();

    iflags.save_uinwater = u.uinwater, iflags.save_uburied = u.uburied;
    u.uinwater = u.uburied = 0;

    /* show chest traps first, so that subsequent floor trap display
       will override if both types are present at the same location */
    (void) detect_obj_traps(fobj, TRUE, cursed_src);
    (void) detect_obj_traps(level.buriedobjlist, TRUE, cursed_src);
    for (mon = fmon; mon; mon = mon->nmon) {
	if (DEADMONSTER(mon)) continue;
	(void) detect_obj_traps(mon->minvent, TRUE, cursed_src);
    }
    (void) detect_obj_traps(invent, TRUE, cursed_src);

    for (ttmp = ftrap; ttmp; ttmp = ttmp->ntrap)
	sense_trap(ttmp, 0, 0, cursed_src);

    for (door = 0; door < doorindex; door++) {
	cc = doors[door];
	if (levl[cc.x][cc.y].doormask & D_TRAPPED)
	    sense_trap((struct trap *)0, cc.x, cc.y, cursed_src);
    }

    /* redisplay hero unless sense_trap() revealed something at <ux,uy> */
    glyph = glyph_at(u.ux, u.uy);
    if (!(glyph_is_trap(glyph) || glyph_is_object(glyph)))
	newsym(u.ux, u.uy);
    u.uinwater = iflags.save_uinwater, u.uburied = iflags.save_uburied;

    You_feel("%s.", cursed_src ? "very greedy" : "entrapped");
    /* wait for user to respond, then reset map display to normal */
    display_nhwindow(WIN_MAP, TRUE);
    docrt();
    if (Underwater) under_water(2);
    if (u.uburied) under_ground(2);
    return(0);
}

const char *
level_distance(where)
d_level *where;
{
    register schar ll = depth(&u.uz) - depth(where);
    register boolean indun = (u.uz.dnum == where->dnum);

    if (ll < 0) {
	if (ll < (-8 - rn2(3)))
	    if (!indun)	return "far away";
	    else	return "far below";
	else if (ll < -1)
	    if (!indun)	return "away below you";
	    else	return "below you";
	else
	    if (!indun)	return "in the distance";
	    else	return "just below";
    } else if (ll > 0) {
	if (ll > (8 + rn2(3)))
	    if (!indun)	return "far away";
	    else	return "far above";
	else if (ll > 1)
	    if (!indun)	return "away above you";
	    else	return "above you";
	else
	    if (!indun)	return "in the distance";
	    else	return "just above";
    } else
	    if (!indun)	return "in the distance";
	    else	return "near you";
}

static const struct {
    const char *what;
    d_level *where;
} level_detects[] = {
  { "Delphi", &oracle_level },
  { "Medusa's lair", &medusa_level },
  { "a castle", &stronghold_level },
  { "the Wizard of Yendor's tower", &wiz1_level },
};

void
use_crystal_ball(obj)
struct obj *obj;
{
    char ch;
    int oops;

    if (Blind) {
	pline("Too bad you can't see %s.", the(xname(obj)));
	return;
    }
    oops = (rnd(20) > ACURR(A_INT) || obj->cursed);
    if (oops && (obj->spe > 0)) {
	switch (rnd(obj->oartifact ? 4 : 5)) {
	case 1 : pline("%s too much to comprehend!", Tobjnam(obj, "are"));
	    break;
	case 2 : pline("%s you!", Tobjnam(obj, "confuse"));
	    make_confused((HConfusion & TIMEOUT) + (long)rnd(100), FALSE);
	    break;
	case 3 : if (!resists_blnd(&youmonst)) {
		pline("%s your vision!", Tobjnam(obj, "damage"));
		make_blinded((Blinded & TIMEOUT) + (long)rnd(100), FALSE);
		if (!Blind) Your1(vision_clears);
	    } else {
		pline("%s your vision.", Tobjnam(obj, "assault"));
		You("are unaffected!");
	    }
	    break;
	case 4 : pline("%s your mind!", Tobjnam(obj, "zap"));
	    (void) make_hallucinated((HHallucination & TIMEOUT) +
				     (long)rnd(100), FALSE, 0L);
	    break;
	case 5 : pline("%s!", Tobjnam(obj, "explode"));
	    useup(obj);
	    obj = 0;	/* it's gone */
	    /* physical damage cause by the shards and force */
	    losehp(Maybe_Half_Phys(rnd(30)),
			"exploding crystal ball", KILLED_BY_AN);
	    break;
	}
	if (obj) consume_obj_charge(obj, TRUE);
	return;
    }

    if (Hallucination) {
	if (!obj->spe) {
	    pline("All you see is funky %s haze.", hcolor((char *)0));
	} else {
	    switch(rnd(6)) {
	    case 1 : You("grok some groovy globs of incandescent lava.");
		break;
	    case 2 : pline("Whoa!  Psychedelic colors, %s!",
			   poly_gender() == 1 ? "babe" : "dude");
		break;
	    case 3 : pline_The("crystal pulses with sinister %s light!",
				hcolor((char *)0));
		break;
	    case 4 : You_see("goldfish swimming above fluorescent rocks.");
		break;
	    case 5 : You_see("tiny snowflakes spinning around a miniature farmhouse.");
		break;
	    default: pline("Oh wow... like a kaleidoscope!");
		break;
	    }
	    consume_obj_charge(obj, TRUE);
	}
	return;
    }

    /* read a single character */
    if (flags.verbose) You("may look for an object or monster symbol.");
    ch = yn_function("What do you look for?", (char *)0, '\0');
    /* Don't filter out ' ' here; it has a use */
    if ((ch != def_monsyms[S_GHOST].sym) && index(quitchars,ch)) { 
	if (flags.verbose) pline1(Never_mind);
	return;
    }
    You("peer into %s...", the(xname(obj)));
    nomul(-rnd(10));
    multi_reason = "gazing into a crystal ball";
    nomovemsg = "";
    if (obj->spe <= 0)
	pline_The("vision is unclear.");
    else {
	int class;
	int ret = 0;

	makeknown(CRYSTAL_BALL);
	consume_obj_charge(obj, TRUE);

	/* special case: accept ']' as synonym for mimic
	 * we have to do this before the def_char_to_objclass check
	 */
	if (ch == DEF_MIMIC_DEF) ch = DEF_MIMIC;

	if ((class = def_char_to_objclass(ch)) != MAXOCLASSES)
		ret = object_detect((struct obj *)0, class);
	else if ((class = def_char_to_monclass(ch)) != MAXMCLASSES)
		ret = monster_detect((struct obj *)0, class);
	else if (iflags.bouldersym && (ch == iflags.bouldersym))
		ret = object_detect((struct obj *)0, ROCK_CLASS);
	else switch(ch) {
		case '^':
		    ret = trap_detect((struct obj *)0);
		    break;
		default:
		    {
		    int i = rn2(SIZE(level_detects));
		    You_see("%s, %s.",
			level_detects[i].what,
			level_distance(level_detects[i].where));
		    }
		    ret = 0;
		    break;
	}

	if (ret) {
	    if (!rn2(100))  /* make them nervous */
		You_see("the Wizard of Yendor gazing out at you.");
	    else pline_The("vision is unclear.");
	}
    }
    return;
}

STATIC_OVL void
show_map_spot(x, y)
register int x, y;
{
    struct rm *lev;
    struct trap *t;
    int oldglyph;

    if (Confusion && rn2(7)) return;
    lev = &levl[x][y];

    lev->seenv = SVALL;

    /* Secret corridors are found, but not secret doors. */
    if (lev->typ == SCORR) {
	lev->typ = CORR;
	unblock_point(x,y);
    }

    /*
     * Force the real background, then if it's not furniture and there's
     * a known trap there, display the trap, else if there was an object
     * shown there, redisplay the object.  So during mapping, furniture
     * takes precedence over traps, which take precedence over objects,
     * opposite to how normal vision behaves.
     */
    oldglyph = glyph_at(x, y);
    if (level.flags.hero_memory) {
	magic_map_background(x, y, 0);
	newsym(x, y);			/* show it, if not blocked */
    } else {
	magic_map_background(x, y, 1);	/* display it */
    }
    if (!IS_FURNITURE(lev->typ)) {
	if ((t = t_at(x, y)) != 0 && t->tseen) {
	    map_trap(t, 1);
	} else if (glyph_is_trap(oldglyph) || glyph_is_object(oldglyph)) {
	    show_glyph(x, y, oldglyph);
	    if (level.flags.hero_memory) lev->glyph = oldglyph;
	}
    }
}

void
do_mapping()
{
    register int zx, zy;

    iflags.save_uinwater = u.uinwater, iflags.save_uburied = u.uburied;
    u.uinwater = u.uburied = 0;
    for (zx = 1; zx < COLNO; zx++)
	for (zy = 0; zy < ROWNO; zy++)
	    show_map_spot(zx, zy);
    u.uinwater = iflags.save_uinwater, u.uburied = iflags.save_uburied;
    if (!level.flags.hero_memory || Underwater) {
	flush_screen(1);			/* flush temp screen */
	display_nhwindow(WIN_MAP, TRUE);	/* wait */
	docrt();
    }
    exercise(A_WIS, TRUE);
}

void
do_vicinity_map()
{
    register int zx, zy;
    int lo_y = (u.uy-5 < 0 ? 0 : u.uy-5),
	hi_y = (u.uy+6 > ROWNO ? ROWNO : u.uy+6),
	lo_x = (u.ux-9 < 1 ? 1 : u.ux-9),	/* avoid column 0 */
	hi_x = (u.ux+10 > COLNO ? COLNO : u.ux+10);

    for (zx = lo_x; zx < hi_x; zx++)
	for (zy = lo_y; zy < hi_y; zy++)
	    show_map_spot(zx, zy);

    if (!level.flags.hero_memory || Underwater) {
	flush_screen(1);			/* flush temp screen */
	display_nhwindow(WIN_MAP, TRUE);	/* wait */
	docrt();
    }
}

/* convert a secret door into a normal door */
void
cvt_sdoor_to_door(lev)
struct rm *lev;
{
	int newmask = lev->doormask & ~WM_MASK;

	if (Is_rogue_level(&u.uz))
	    /* rogue didn't have doors, only doorways */
	    newmask = D_NODOOR;
	else
	    /* newly exposed door is closed */
	    if (!(newmask & D_LOCKED)) newmask |= D_CLOSED;

	lev->typ = DOOR;
	lev->doormask = newmask;
}


STATIC_PTR void
findone(zx,zy,num)
int zx,zy;
genericptr_t num;
{
	register struct trap *ttmp;
	register struct monst *mtmp;

	if(levl[zx][zy].typ == SDOOR) {
		cvt_sdoor_to_door(&levl[zx][zy]);	/* .typ = DOOR */
		magic_map_background(zx, zy, 0);
		newsym(zx, zy);
		(*(int*)num)++;
	} else if(levl[zx][zy].typ == SCORR) {
		levl[zx][zy].typ = CORR;
		unblock_point(zx,zy);
		magic_map_background(zx, zy, 0);
		newsym(zx, zy);
		(*(int*)num)++;
	} else if ((ttmp = t_at(zx, zy)) != 0) {
		if(!ttmp->tseen && ttmp->ttyp != STATUE_TRAP) {
			ttmp->tseen = 1;
			newsym(zx,zy);
			(*(int*)num)++;
		}
	} else if ((mtmp = m_at(zx, zy)) != 0) {
		if(mtmp->m_ap_type) {
			seemimic(mtmp);
			(*(int*)num)++;
		}
		if (mtmp->mundetected &&
		    (is_hider(mtmp->data) || mtmp->data->mlet == S_EEL)) {
			mtmp->mundetected = 0;
			newsym(zx, zy);
			(*(int*)num)++;
		}
		if (!canspotmon(mtmp) &&
				    !glyph_is_invisible(levl[zx][zy].glyph))
			map_invisible(zx, zy);
	} else if (glyph_is_invisible(levl[zx][zy].glyph)) {
		unmap_object(zx, zy);
		newsym(zx, zy);
		(*(int*)num)++;
	}
}

STATIC_PTR void
openone(zx,zy,num)
int zx,zy;
genericptr_t num;
{
	register struct trap *ttmp;
	register struct obj *otmp;
	int *num_p = (int *)num;

	if(OBJ_AT(zx, zy)) {
		for(otmp = level.objects[zx][zy];
				otmp; otmp = otmp->nexthere) {
		    if(Is_box(otmp) && otmp->olocked) {
			otmp->olocked = 0;
			(*num_p)++;
		    }
		}
		/* let it fall to the next cases. could be on trap. */
	}
	if(levl[zx][zy].typ == SDOOR || (levl[zx][zy].typ == DOOR &&
		      (levl[zx][zy].doormask & (D_CLOSED|D_LOCKED)))) {
		if(levl[zx][zy].typ == SDOOR)
		    cvt_sdoor_to_door(&levl[zx][zy]);	/* .typ = DOOR */
		if(levl[zx][zy].doormask & D_TRAPPED) {
		    if(distu(zx, zy) < 3) b_trapped("door", 0);
		    else Norep("You %s an explosion!",
				cansee(zx, zy) ? "see" :
				   (!Deaf ? "hear" :
						"feel the shock of"));
		    wake_nearto(zx, zy, 11*11);
		    levl[zx][zy].doormask = D_NODOOR;
		} else
		    levl[zx][zy].doormask = D_ISOPEN;
		unblock_point(zx, zy);
		newsym(zx, zy);
		(*num_p)++;
	} else if(levl[zx][zy].typ == SCORR) {
		levl[zx][zy].typ = CORR;
		unblock_point(zx, zy);
		newsym(zx, zy);
		(*num_p)++;
	} else if ((ttmp = t_at(zx, zy)) != 0) {
		struct monst *mon;
		boolean dummy;	/* unneeded "you notice it arg" */

		if (!ttmp->tseen && ttmp->ttyp != STATUE_TRAP) {
		    ttmp->tseen = 1;
		    newsym(zx,zy);
		    (*num_p)++;
		}
		mon = (zx == u.ux && zy == u.uy) ? &youmonst : m_at(zx, zy);
		if (openholdingtrap(mon, &dummy) ||
			openfallingtrap(mon, TRUE, &dummy))
		    (*num_p)++;
	} else if (find_drawbridge(&zx, &zy)) {
		/* make sure it isn't an open drawbridge */
		open_drawbridge(zx, zy);
		(*num_p)++;
	}
}

int
findit()	/* returns number of things found */
{
	int num = 0;

	if(u.uswallow) return(0);
	do_clear_area(u.ux, u.uy, BOLT_LIM, findone, (genericptr_t) &num);
	return(num);
}

int
openit()	/* returns number of things found and opened */
{
	int num = 0;

	if(u.uswallow) {
		if (is_animal(u.ustuck->data)) {
			if (Blind) pline("Its mouth opens!");
			else pline("%s opens its mouth!", Monnam(u.ustuck));
		}
		expels(u.ustuck, u.ustuck->data, TRUE);
		return(-1);
	}

	do_clear_area(u.ux, u.uy, BOLT_LIM, openone, (genericptr_t) &num);
	return(num);
}

/* callback hack for overriding vision in do_clear_area() */
boolean
detecting(func)
    void FDECL((*func), (int,int,genericptr_t));
{
    return (func == findone || func == openone);
}

void
find_trap(trap)
struct trap *trap;
{
    int tt = what_trap(trap->ttyp);
    boolean cleared = FALSE;

    trap->tseen = 1;
    exercise(A_WIS, TRUE);
    if (Blind)
	feel_location(trap->tx, trap->ty);
    else
	newsym(trap->tx, trap->ty);

    if (levl[trap->tx][trap->ty].glyph != trap_to_glyph(trap)) {
    	/* There's too much clutter to see your find otherwise */
	cls();
	map_trap(trap, 1);
	display_self();
	cleared = TRUE;
    }

    You("find %s.", an(defsyms[trap_to_defsym(tt)].explanation));

    if (cleared) {
	display_nhwindow(WIN_MAP, TRUE);	/* wait */
	docrt();
    }
}

int
dosearch0(aflag)
register int aflag;	/* intrinsic autosearch vs explicit searching */
{
#ifdef GCC_BUG
/* some versions of gcc seriously muck up nested loops. if you get strange
   crashes while searching in a version compiled with gcc, try putting
   #define GCC_BUG in *conf.h (or adding -DGCC_BUG to CFLAGS in the
   makefile).
 */
	volatile xchar x, y;
#else
	register xchar x, y;
#endif
	register struct trap *trap;
	register struct monst *mtmp;

	if(u.uswallow) {
		if (!aflag)
			pline("What are you looking for?  The exit?");
	} else {
	    int fund = (uwep && uwep->oartifact &&
		    spec_ability(uwep, SPFX_SEARCH)) ?
		    uwep->spe : 0;
	    if (ublindf && ublindf->otyp == LENSES && !Blind)
		    fund += 2; /* JDS: lenses help searching */
	    if (fund > 5) fund = 5;
	    for(x = u.ux-1; x < u.ux+2; x++)
	      for(y = u.uy-1; y < u.uy+2; y++) {
		if(!isok(x,y)) continue;
		if(x != u.ux || y != u.uy) {
		    if (Blind && !aflag) feel_location(x,y);
		    if(levl[x][y].typ == SDOOR) {
			if(rnl(7-fund)) continue;
			cvt_sdoor_to_door(&levl[x][y]);	/* .typ = DOOR */
			exercise(A_WIS, TRUE);
			nomul(0);
			feel_location(x, y);	/* make sure it shows up */
			You("find a hidden door.");
		    } else if(levl[x][y].typ == SCORR) {
			if(rnl(7-fund)) continue;
			levl[x][y].typ = CORR;
			unblock_point(x,y);	/* vision */
			exercise(A_WIS, TRUE);
			nomul(0);
			feel_location(x, y);	/* make sure it shows up */
			You("find a hidden passage.");
		    } else {
		/* Be careful not to find anything in an SCORR or SDOOR */
			if((mtmp = m_at(x, y)) && !aflag) {
			    if(mtmp->m_ap_type) {
				seemimic(mtmp);
		find:		exercise(A_WIS, TRUE);
				if (!canspotmon(mtmp)) {
				    if (glyph_is_invisible(levl[x][y].glyph)) {
					/* found invisible monster in a square
					 * which already has an 'I' in it.
					 * Logically, this should still take
					 * time and lead to a return(1), but if
					 * we did that the player would keep
					 * finding the same monster every turn.
					 */
					continue;
				    } else {
					You_feel("an unseen monster!");
					map_invisible(x, y);
				    }
				} else if (!sensemon(mtmp))
				    You("find %s.", mtmp->mtame ?
						y_monnam(mtmp) :
						a_monnam(mtmp));
				return(1);
			    }
			    if(!canspotmon(mtmp)) {
				if (mtmp->mundetected &&
				   (is_hider(mtmp->data) || mtmp->data->mlet == S_EEL))
					mtmp->mundetected = 0;
				newsym(x,y);
				goto find;
			    }
			}

			/* see if an invisible monster has moved--if Blind,
			 * feel_location() already did it
			 */
			if (!aflag && !mtmp && !Blind &&
				    glyph_is_invisible(levl[x][y].glyph)) {
			    unmap_object(x,y);
			    newsym(x,y);
			}

			if ((trap = t_at(x,y)) && !trap->tseen && !rnl(8)) {
			    nomul(0);

			    if (trap->ttyp == STATUE_TRAP) {
				if (activate_statue_trap(trap, x, y, FALSE))
				    exercise(A_WIS, TRUE);
				return(1);
			    } else {
				find_trap(trap);
			    }
			}
		    }
		}
	    }
	}
	return(1);
}

/* the 's' command -- explicit searching */
int
dosearch()
{
	return(dosearch0(0));
}

/* Pre-map the sokoban levels */
void
sokoban_detect()
{
	register int x, y;
	register struct trap *ttmp;
	register struct obj *obj;

	/* Map the background and boulders */
	for (x = 1; x < COLNO; x++)
	    for (y = 0; y < ROWNO; y++) {
		levl[x][y].seenv = SVALL;
		levl[x][y].waslit = TRUE;
		map_background(x, y, 1);
		if ((obj = sobj_at(BOULDER, x, y)) != 0)
		    map_object(obj, 1);
	    }

	/* Map the traps */
	for (ttmp = ftrap; ttmp; ttmp = ttmp->ntrap) {
	    ttmp->tseen = 1;
	    map_trap(ttmp, 1);
	    /* set sokoban_rules when there is at least one pit or hole */
	    if (ttmp->ttyp == PIT || ttmp->ttyp == HOLE)
		Sokoban = 1;
	}
}

/* idea from crawl; show known portion of map without any monsters,
   objects, or traps occluding the view of the underlying terrain */
void
reveal_terrain(full)
boolean full;	/* wizard|explore modes allow player to request full map */
{
    int x, y, glyph, S_stone_glyph;
    uchar seenv;
    struct monst *mtmp;

    if ((Hallucination || Stunned || Confusion) && !full) {
	You("are too disoriented for this.");
    } else {
	iflags.save_uinwater = u.uinwater, iflags.save_uburied = u.uburied;
	u.uinwater = u.uburied = 0;
	S_stone_glyph = cmap_to_glyph(S_stone);
	/* rewrite the map, displaying map background for seen spots
	   (all spots seen if 'full') and stone everywhere else */
	for (x = 1; x < COLNO; x++)
	    for (y = 0; y < ROWNO; y++) {
		seenv = levl[x][y].seenv;
		if (full) {
		    levl[x][y].seenv = SVALL;
		    glyph = back_to_glyph(x, y);
		    levl[x][y].seenv = seenv;
		} else {
		    if (!level.flags.hero_memory && !cansee(x, y))
			seenv = 0;
		    glyph = seenv ? back_to_glyph(x, y) : S_stone_glyph;
		    /* need to show mimic-as-furniture so that #terrain can't
		       be used to spot mimics, but this is only approximate;
		       mimic might have moved and hid here after the player
		       last saw this spot as some other type of terrain */
		    if (seenv && (mtmp = m_at(x, y)) != 0 &&
			    mtmp->m_ap_type == M_AP_FURNITURE)
			glyph = cmap_to_glyph(mtmp->mappearance);
		}
		show_glyph(x, y, glyph);
	    }
	/* [TODO: highlight hero's location somehow] */
	u.uinwater = iflags.save_uinwater, u.uburied = iflags.save_uburied;
	flush_screen(1);
	pline("Showing underlying terrain only...");
	display_nhwindow(WIN_MAP, TRUE);	/* give "--More--" prompt */
	docrt();	/* redraw the screen, restoring regular map */
	if (Underwater) under_water(2);
	if (u.uburied) under_ground(2);
    }
    return;
}

/*detect.c*/