/*      $OpenBSD: hack.shk.c,v 1.13 2016/01/09 18:33:15 mestre Exp $    */

/*
 * Copyright (c) 1985, Stichting Centrum voor Wiskunde en Informatica,
 * Amsterdam
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * - 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.
 *
 * - Neither the name of the Stichting Centrum voor Wiskunde en
 * Informatica, 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER
 * 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.
 */

/*
 * Copyright (c) 1982 Jay Fenlason <hack@gnu.org>
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``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 AUTHOR 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 <stdio.h>
#include <stdlib.h>

#include "hack.h"

#ifdef QUEST
int shlevel = 0;
struct monst *shopkeeper = 0;
struct obj *billobjs = 0;

void
obfree(struct obj *obj, struct obj *merge)
{
        free(obj);
}

int
inshop(void)
{
        return(0);
}

void
shopdig(int a)
{}

void
addtobill(struct obj *ign)
{}

void
subfrombill(struct obj *ign)
{}

void
splitbill(struct obj *ign, struct obj *ign2)
{}

int
dopay(void)
{
        return(0);
}

void
paybill(void)
{}

int
doinvbill(int a)
{
        return(0);
}

void
shkdead(struct monst *ign)
{}

int
shkcatch(struct obj *ign)
{
        return(0);
}

int
shk_move(struct monst *ign)
{
        return(0);
}

void
replshk(struct monst *mtmp, struct monst *mtmp2)
{}

char *
shkname(struct monst *ign)
{
        return("");
}

#else /* QUEST */
#include "hack.mfndpos.h"
#include "def.eshk.h"

#define ESHK(mon)       ((struct eshk *)(&(mon->mextra[0])))
#define NOTANGRY(mon)   mon->mpeaceful
#define ANGRY(mon)      !NOTANGRY(mon)

extern char plname[];

/* Descriptor of current shopkeeper. Note that the bill need not be
 * per-shopkeeper, since it is valid only when in a shop.
 */
static struct monst *shopkeeper = 0;
static struct bill_x *bill;
static int shlevel = 0; /* level of this shopkeeper */
struct obj *billobjs;   /* objects on bill with bp->useup */
                                /* only accessed here and by save & restore */
static long int total;          /* filled by addupbill() */
static long int followmsg;      /* last time of follow message */

/*
 *      invariants: obj->unpaid iff onbill(obj) [unless bp->useup]
 *              obj->quan <= bp->bquan
 */


char shtypes[] = {      /* 8 shoptypes: 7 specialized, 1 mixed */
        RING_SYM, WAND_SYM, WEAPON_SYM, FOOD_SYM, SCROLL_SYM,
        POTION_SYM, ARMOR_SYM, 0
};

static char *shopnam[] = {
        "engagement ring", "walking cane", "antique weapon",
        "delicatessen", "second hand book", "liquor",
        "used armor", "assorted antiques"
};

static void setpaid(void);
static void addupbill(void);
static void findshk(int);
static struct bill_x *onbill(struct obj *);
static void pay(long, struct monst *);
static int  dopayobj(struct bill_x *);
static struct obj *bp_to_obj(struct bill_x *);
static int getprice(struct obj *);
static int realhunger(void);

/* called in do_name.c */
char *
shkname(struct monst *mtmp)
{
        return(ESHK(mtmp)->shknam);
}

void
shkdead(struct monst *mtmp)                             /* called in mon.c */
{
        struct eshk *eshk = ESHK(mtmp);

        if(eshk->shoplevel == dlevel)
                rooms[eshk->shoproom].rtype = 0;
        if(mtmp == shopkeeper) {
                setpaid();
                shopkeeper = 0;
                bill = (struct bill_x *) -1000; /* dump core when referenced */
        }
}

void
replshk(struct monst *mtmp, struct monst *mtmp2)
{
        if(mtmp == shopkeeper) {
                shopkeeper = mtmp2;
                bill = &(ESHK(shopkeeper)->bill[0]);
        }
}

/* caller has checked that shopkeeper exists */
/* either we paid or left the shop or he just died */
static void
setpaid(void)
{
        struct obj *obj;
        struct monst *mtmp;

        for(obj = invent; obj; obj = obj->nobj)
                obj->unpaid = 0;
        for(obj = fobj; obj; obj = obj->nobj)
                obj->unpaid = 0;
        for(obj = fcobj; obj; obj = obj->nobj)
                obj->unpaid = 0;
        for(mtmp = fmon; mtmp; mtmp = mtmp->nmon)
                for(obj = mtmp->minvent; obj; obj = obj->nobj)
                        obj->unpaid = 0;
        for(mtmp = fallen_down; mtmp; mtmp = mtmp->nmon)
                for(obj = mtmp->minvent; obj; obj = obj->nobj)
                        obj->unpaid = 0;
        while ((obj = billobjs)) {
                billobjs = obj->nobj;
                free(obj);
        }
        ESHK(shopkeeper)->billct = 0;
}

/* delivers result in total */
/* caller has checked that shopkeeper exists */
static void
addupbill(void)
{
        int ct = ESHK(shopkeeper)->billct;
        struct bill_x *bp = bill;

        total = 0;
        while(ct--){
                total += bp->price * bp->bquan;
                bp++;
        }
}

int
inshop(void)
{
        int roomno = inroom(u.ux,u.uy);

        /* Did we just leave a shop? */
        if(u.uinshop &&
            (u.uinshop != roomno + 1 || shlevel != dlevel || !shopkeeper)) {
                if(shopkeeper) {
                    if(ESHK(shopkeeper)->billct) {
                        if(inroom(shopkeeper->mx, shopkeeper->my) 
                            == u.uinshop - 1)   /* ab@unido */
                            pline("Somehow you escaped the shop without paying!");
                        addupbill();
                        pline("You stole for a total worth of %ld zorkmids.",
                                total);
                        ESHK(shopkeeper)->robbed += total;
                        setpaid();
                        if((rooms[ESHK(shopkeeper)->shoproom].rtype == GENERAL)
                            == (rn2(3) == 0))
                            ESHK(shopkeeper)->following = 1;
                    }
                    shopkeeper = 0;
                    shlevel = 0;
                }
                u.uinshop = 0;
        }

        /* Did we just enter a zoo of some kind? */
        if(roomno >= 0) {
                int rt = rooms[roomno].rtype;
                struct monst *mtmp;
                if(rt == ZOO) {
                        pline("Welcome to David's treasure zoo!");
                } else
                if(rt == SWAMP) {
                        pline("It looks rather muddy down here.");
                } else
                if(rt == MORGUE) {
                        if(midnight())
                                pline("Go away! Go away!");
                        else
                                pline("You get an uncanny feeling ...");
                } else
                        rt = 0;
                if(rt != 0) {
                        rooms[roomno].rtype = 0;
                        for(mtmp = fmon; mtmp; mtmp = mtmp->nmon)
                                if(rt != ZOO || !rn2(3))
                                        mtmp->msleep = 0;
                }
        }

        /* Did we just enter a shop? */
        if(roomno >= 0 && rooms[roomno].rtype >= 8) {
            if(shlevel != dlevel || !shopkeeper
                                 || ESHK(shopkeeper)->shoproom != roomno)
                findshk(roomno);
            if(!shopkeeper) {
                rooms[roomno].rtype = 0;
                u.uinshop = 0;
            } else if(!u.uinshop){
                if(!ESHK(shopkeeper)->visitct ||
                    strncmp(ESHK(shopkeeper)->customer, plname, PL_NSIZ)){

                    /* He seems to be new here */
                    ESHK(shopkeeper)->visitct = 0;
                    ESHK(shopkeeper)->following = 0;
                    (void) strlcpy(ESHK(shopkeeper)->customer,plname,PL_NSIZ);
                    NOTANGRY(shopkeeper) = 1;
                }
                if(!ESHK(shopkeeper)->following) {
                    boolean box, pick;

                    pline("Hello %s! Welcome%s to %s's %s shop!",
                        plname,
                        ESHK(shopkeeper)->visitct++ ? " again" : "",
                        shkname(shopkeeper),
                        shopnam[rooms[ESHK(shopkeeper)->shoproom].rtype - 8] );
                    box = carrying(ICE_BOX);
                    pick = carrying(PICK_AXE);
                    if(box || pick) {
                        if(dochug(shopkeeper)) {
                                u.uinshop = 0;  /* he died moving */
                                return(0);
                        }
                        pline("Will you please leave your %s outside?",
                            (box && pick) ? "box and pick-axe" :
                            box ? "box" : "pick-axe");
                    }
                }
                u.uinshop = roomno + 1;
            }
        }
        return(u.uinshop);
}

static void
findshk(int roomno)
{
        struct monst *mtmp;

        for(mtmp = fmon; mtmp; mtmp = mtmp->nmon)
            if(mtmp->isshk && ESHK(mtmp)->shoproom == roomno
                           && ESHK(mtmp)->shoplevel == dlevel) {
                shopkeeper = mtmp;
                bill = &(ESHK(shopkeeper)->bill[0]);
                shlevel = dlevel;
                if(ANGRY(shopkeeper) &&
                   strncmp(ESHK(shopkeeper)->customer,plname,PL_NSIZ))
                        NOTANGRY(shopkeeper) = 1;
                /* billobjs = 0; -- this is wrong if we save in a shop */
                /* (and it is harmless to have too many things in billobjs) */
                return;
        }
        shopkeeper = 0;
        shlevel = 0;
        bill = (struct bill_x *) -1000; /* dump core when referenced */
}

static struct bill_x *
onbill(struct obj *obj)
{
        struct bill_x *bp;

        if(!shopkeeper) return(NULL);
        for(bp = bill; bp < &bill[ESHK(shopkeeper)->billct]; bp++)
                if(bp->bo_id == obj->o_id) {
                        if(!obj->unpaid) pline("onbill: paid obj on bill?");
                        return(bp);
                }
        if(obj->unpaid) pline("onbill: unpaid obj not on bill?");
        return(NULL);
}

/* called with two args on merge */
void
obfree(struct obj *obj, struct obj *merge)
{
        struct bill_x *bp = onbill(obj);
        struct bill_x *bpm;

        if(bp) {
                if(!merge){
                        bp->useup = 1;
                        obj->unpaid = 0;        /* only for doinvbill */
                        obj->nobj = billobjs;
                        billobjs = obj;
                        return;
                }
                bpm = onbill(merge);
                if(!bpm){
                        /* this used to be a rename */
                        impossible("obfree: not on bill??");
                        return;
                } else {
                        /* this was a merger */
                        bpm->bquan += bp->bquan;
                        ESHK(shopkeeper)->billct--;
                        *bp = bill[ESHK(shopkeeper)->billct];
                }
        }
        free(obj);
}

static void
pay(long tmp, struct monst *shkp)
{
        long robbed = ESHK(shkp)->robbed;

        u.ugold -= tmp;
        shkp->mgold += tmp;
        flags.botl = 1;
        if(robbed) {
                robbed -= tmp;
                if(robbed < 0) robbed = 0;
                ESHK(shkp)->robbed = robbed;
        }
}

int
dopay(void)
{
        long ltmp;
        struct bill_x *bp;
        struct monst *shkp;
        int pass, tmp;

        multi = 0;
        (void) inshop();
        for(shkp = fmon; shkp; shkp = shkp->nmon)
                if(shkp->isshk && dist(shkp->mx,shkp->my) < 3)
                        break;
        if(!shkp && u.uinshop &&
           inroom(shopkeeper->mx,shopkeeper->my) == ESHK(shopkeeper)->shoproom)
                shkp = shopkeeper;

        if(!shkp) {
                pline("There is nobody here to receive your payment.");
                return(0);
        }
        ltmp = ESHK(shkp)->robbed;
        if(shkp != shopkeeper && NOTANGRY(shkp)) {
                if(!ltmp) {
                        pline("You do not owe %s anything.", monnam(shkp));
                } else
                if(!u.ugold) {
                        pline("You have no money.");
                } else {
                    long ugold = u.ugold;

                    if(u.ugold > ltmp) {
                        pline("You give %s the %ld gold pieces he asked for.",
                                monnam(shkp), ltmp);
                        pay(ltmp, shkp);
                    } else {
                        pline("You give %s all your gold.", monnam(shkp));
                        pay(u.ugold, shkp);
                    }
                    if(ugold < ltmp/2) {
                        pline("Unfortunately, he doesn't look satisfied.");
                    } else {
                        ESHK(shkp)->robbed = 0;
                        ESHK(shkp)->following = 0;
                        if(ESHK(shkp)->shoplevel != dlevel) {
                        /* For convenience's sake, let him disappear */
                            shkp->minvent = 0;          /* %% */
                            shkp->mgold = 0;
                            mondead(shkp);
                        }
                    }
                }
                return(1);
        }
                
        if(!ESHK(shkp)->billct){
                pline("You do not owe %s anything.", monnam(shkp));
                if(!u.ugold){
                        pline("Moreover, you have no money.");
                        return(1);
                }
                if(ESHK(shkp)->robbed){
#define min(a,b)        ((a<b)?a:b)
                    pline("But since his shop has been robbed recently,");
                    pline("you %srepay %s's expenses.",
                      (u.ugold < ESHK(shkp)->robbed) ? "partially " : "",
                      monnam(shkp));
                    pay(min(u.ugold, ESHK(shkp)->robbed), shkp);
                    ESHK(shkp)->robbed = 0;
                    return(1);
                }
                if(ANGRY(shkp)){
                        pline("But in order to appease %s,",
                                amonnam(shkp, "angry"));
                        if(u.ugold >= 1000){
                                ltmp = 1000;
                                pline(" you give him 1000 gold pieces.");
                        } else {
                                ltmp = u.ugold;
                                pline(" you give him all your money.");
                        }
                        pay(ltmp, shkp);
                        if(strncmp(ESHK(shkp)->customer, plname, PL_NSIZ)
                           || rn2(3)){
                                pline("%s calms down.", Monnam(shkp));
                                NOTANGRY(shkp) = 1;
                        } else  pline("%s is as angry as ever.",
                                        Monnam(shkp));
                }
                return(1);
        }
        if(shkp != shopkeeper) {
                impossible("dopay: not to shopkeeper?");
                if(shopkeeper) setpaid();
                return(0);
        }
        for(pass = 0; pass <= 1; pass++) {
                tmp = 0;
                while(tmp < ESHK(shopkeeper)->billct) {
                        bp = &bill[tmp];
                        if(!pass && !bp->useup) {
                                tmp++;
                                continue;
                        }
                        if(!dopayobj(bp)) return(1);
                        bill[tmp] = bill[--ESHK(shopkeeper)->billct];
                }
        }
        pline("Thank you for shopping in %s's %s store!",
                shkname(shopkeeper),
                shopnam[rooms[ESHK(shopkeeper)->shoproom].rtype - 8]);
        NOTANGRY(shopkeeper) = 1;
        return(1);
}

/* return 1 if paid successfully */
/*        0 if not enough money */
/*       -1 if object could not be found (but was paid) */
static int
dopayobj(struct bill_x *bp)
{
        struct obj *obj;
        long ltmp;

        /* find the object on one of the lists */
        obj = bp_to_obj(bp);

        if(!obj) {
                impossible("Shopkeeper administration out of order.");
                setpaid();      /* be nice to the player */
                return(0);
        }

        if(!obj->unpaid && !bp->useup){
                impossible("Paid object on bill??");
                return(1);
        }
        obj->unpaid = 0;
        ltmp = bp->price * bp->bquan;
        if(ANGRY(shopkeeper)) ltmp += ltmp/3;
        if(u.ugold < ltmp){
                pline("You don't have gold enough to pay %s.",
                        doname(obj));
                obj->unpaid = 1;
                return(0);
        }
        pay(ltmp, shopkeeper);
        pline("You bought %s for %ld gold piece%s.",
                doname(obj), ltmp, plur(ltmp));
        if(bp->useup) {
                struct obj *otmp = billobjs;
                if(obj == billobjs)
                        billobjs = obj->nobj;
                else {
                        while(otmp && otmp->nobj != obj) otmp = otmp->nobj;
                        if(otmp) otmp->nobj = obj->nobj;
                        else pline("Error in shopkeeper administration.");
                }
                free(obj);
        }
        return(1);
}

/* routine called after dying (or quitting) with nonempty bill */
void
paybill(void)
{
        if(shlevel == dlevel && shopkeeper && ESHK(shopkeeper)->billct){
                addupbill();
                if(total > u.ugold){
                        shopkeeper->mgold += u.ugold;
                        u.ugold = 0;
                pline("%s comes and takes all your possessions.",
                        Monnam(shopkeeper));
                } else {
                        u.ugold -= total;
                        shopkeeper->mgold += total;
        pline("%s comes and takes the %ld zorkmids you owed him.",
                Monnam(shopkeeper), total);
                }
                setpaid();      /* in case we create bones */
        }
}

/* find obj on one of the lists */
static struct obj *
bp_to_obj(struct bill_x *bp)
{
        struct obj *obj;
        struct monst *mtmp;
        unsigned id = bp->bo_id;

        if(bp->useup)
                obj = o_on(id, billobjs);
        else if(!(obj = o_on(id, invent)) &&
                !(obj = o_on(id, fobj)) &&
                !(obj = o_on(id, fcobj))) {
                    for(mtmp = fmon; mtmp; mtmp = mtmp->nmon)
                        if ((obj = o_on(id, mtmp->minvent)))
                            break;
                    for(mtmp = fallen_down; mtmp; mtmp = mtmp->nmon)
                        if ((obj = o_on(id, mtmp->minvent)))
                            break;
                }
        return(obj);
}

/* called in hack.c when we pickup an object */
void
addtobill(struct obj *obj)
{
        struct bill_x *bp;

        if(!inshop() ||
        (u.ux == ESHK(shopkeeper)->shk.x && u.uy == ESHK(shopkeeper)->shk.y) ||
        (u.ux == ESHK(shopkeeper)->shd.x && u.uy == ESHK(shopkeeper)->shd.y) ||
                onbill(obj) /* perhaps we threw it away earlier */
          ) return;
        if(ESHK(shopkeeper)->billct == BILLSZ){
                pline("You got that for free!");
                return;
        }
        bp = &bill[ESHK(shopkeeper)->billct];
        bp->bo_id = obj->o_id;
        bp->bquan = obj->quan;
        bp->useup = 0;
        bp->price = getprice(obj);
        ESHK(shopkeeper)->billct++;
        obj->unpaid = 1;
}

void
splitbill(struct obj *obj, struct obj *otmp)
{
        /* otmp has been split off from obj */
struct bill_x *bp;
int tmp;
        bp = onbill(obj);
        if(!bp) {
                impossible("splitbill: not on bill?");
                return;
        }
        if(bp->bquan < otmp->quan) {
                impossible("Negative quantity on bill??");
        }
        if(bp->bquan == otmp->quan) {
                impossible("Zero quantity on bill??");
        }
        bp->bquan -= otmp->quan;

        /* addtobill(otmp); */
        if(ESHK(shopkeeper)->billct == BILLSZ) otmp->unpaid = 0;
        else {
                tmp = bp->price;
                bp = &bill[ESHK(shopkeeper)->billct];
                bp->bo_id = otmp->o_id;
                bp->bquan = otmp->quan;
                bp->useup = 0;
                bp->price = tmp;
                ESHK(shopkeeper)->billct++;
        }
}

void
subfrombill(struct obj *obj)
{
        long ltmp;
        int tmp;
        struct obj *otmp;
        struct bill_x *bp;

        if(!inshop() || (u.ux == ESHK(shopkeeper)->shk.x && u.uy == ESHK(shopkeeper)->shk.y) ||
                (u.ux == ESHK(shopkeeper)->shd.x && u.uy == ESHK(shopkeeper)->shd.y))
                return;
        if((bp = onbill(obj)) != 0){
                obj->unpaid = 0;
                if(bp->bquan > obj->quan){
                        otmp = newobj(0);
                        *otmp = *obj;
                        bp->bo_id = otmp->o_id = flags.ident++;
                        otmp->quan = (bp->bquan -= obj->quan);
                        otmp->owt = 0;  /* superfluous */
                        otmp->onamelth = 0;
                        bp->useup = 1;
                        otmp->nobj = billobjs;
                        billobjs = otmp;
                        return;
                }
                ESHK(shopkeeper)->billct--;
                *bp = bill[ESHK(shopkeeper)->billct];
                return;
        }
        if(obj->unpaid){
                pline("%s didn't notice.", Monnam(shopkeeper));
                obj->unpaid = 0;
                return;         /* %% */
        }
        /* he dropped something of his own - probably wants to sell it */
        if(shopkeeper->msleep || shopkeeper->mfroz ||
                inroom(shopkeeper->mx,shopkeeper->my) != ESHK(shopkeeper)->shoproom)
                return;
        if(ESHK(shopkeeper)->billct == BILLSZ ||
          ((tmp = shtypes[rooms[ESHK(shopkeeper)->shoproom].rtype-8]) && tmp != obj->olet)
          || strchr("_0", obj->olet)) {
                pline("%s seems not interested.", Monnam(shopkeeper));
                return;
        }
        ltmp = getprice(obj) * obj->quan;
        if(ANGRY(shopkeeper)) {
                ltmp /= 3;
                NOTANGRY(shopkeeper) = 1;
        } else  ltmp /= 2;
        if(ESHK(shopkeeper)->robbed){
                if((ESHK(shopkeeper)->robbed -= ltmp) < 0)
                        ESHK(shopkeeper)->robbed = 0;
pline("Thank you for your contribution to restock this recently plundered shop.");
                return;
        }
        if(ltmp > shopkeeper->mgold)
                ltmp = shopkeeper->mgold;
        pay(-ltmp, shopkeeper);
        if(!ltmp)
        pline("%s gladly accepts %s but cannot pay you at present.",
                Monnam(shopkeeper), doname(obj));
        else
        pline("You sold %s and got %ld gold piece%s.", doname(obj), ltmp,
                plur(ltmp));
}

/* int mode;            0: deliver count 1: paged */
int
doinvbill(int mode)
{
        struct bill_x *bp;
        struct obj *obj;
        long totused, thisused;
        char buf[BUFSZ];

        if(mode == 0) {
            int cnt = 0;

            if(shopkeeper)
                for(bp = bill; bp - bill < ESHK(shopkeeper)->billct; bp++)
                    if(bp->useup ||
                      ((obj = bp_to_obj(bp)) && obj->quan < bp->bquan))
                        cnt++;
            return(cnt);
        }

        if(!shopkeeper) {
                impossible("doinvbill: no shopkeeper?");
                return(0);
        }

        set_pager(0);
        if(page_line("Unpaid articles already used up:") || page_line(""))
            goto quit;

        totused = 0;
        for(bp = bill; bp - bill < ESHK(shopkeeper)->billct; bp++) {
            obj = bp_to_obj(bp);
            if(!obj) {
                impossible("Bad shopkeeper administration.");
                goto quit;
            }
            if(bp->useup || bp->bquan > obj->quan) {
                int cnt, oquan, uquan;

                oquan = obj->quan;
                uquan = (bp->useup ? bp->bquan : bp->bquan - oquan);
                thisused = bp->price * uquan;
                totused += thisused;
                obj->quan = uquan;              /* cheat doname */
                (void) snprintf(buf, sizeof buf, "x -  %s", doname(obj));
                obj->quan = oquan;              /* restore value */
                for(cnt = 0; buf[cnt]; cnt++);
                while(cnt < 50)
                        buf[cnt++] = ' ';
                (void) snprintf(&buf[cnt], sizeof buf - cnt,
                    " %5ld zorkmids", thisused);
                if(page_line(buf))
                        goto quit;
            }
        }
        (void) snprintf(buf, sizeof buf, "Total:%50ld zorkmids", totused);
        if(page_line("") || page_line(buf))
                goto quit;
        set_pager(1);
        return(0);
quit:
        set_pager(2);
        return(0);
}

static int
getprice(struct obj *obj)
{
        int tmp, ac;

        switch(obj->olet){
        case AMULET_SYM:
                tmp = 10*rnd(500);
                break;
        case TOOL_SYM:
                tmp = 10*rnd((obj->otyp == EXPENSIVE_CAMERA) ? 150 : 30);
                break;
        case RING_SYM:
                tmp = 10*rnd(100);
                break;
        case WAND_SYM:
                tmp = 10*rnd(100);
                break;
        case SCROLL_SYM:
                tmp = 10*rnd(50);
#ifdef MAIL
                if(obj->otyp == SCR_MAIL)
                        tmp = rnd(5);
#endif /* MAIL */
                break;
        case POTION_SYM:
                tmp = 10*rnd(50);
                break;
        case FOOD_SYM:
                tmp = 10*rnd(5 + (2000/realhunger()));
                break;
        case GEM_SYM:
                tmp = 10*rnd(20);
                break;
        case ARMOR_SYM:
                ac = ARM_BONUS(obj);
                if(ac <= -10)           /* probably impossible */
                        ac = -9;
                tmp = 100 + ac*ac*rnd(10+ac);
                break;
        case WEAPON_SYM:
                if(obj->otyp < BOOMERANG)
                        tmp = 5*rnd(10);
                else if(obj->otyp == LONG_SWORD ||
                        obj->otyp == TWO_HANDED_SWORD)
                        tmp = 10*rnd(150);
                else    tmp = 10*rnd(75);
                break;
        case CHAIN_SYM:
                pline("Strange ..., carrying a chain?");
        case BALL_SYM:
                tmp = 10;
                break;
        default:
                tmp = 10000;
        }
        return(tmp);
}

/* not completely foolproof */
static int
realhunger(void)
{
        int tmp = u.uhunger;
        struct obj *otmp = invent;

        while(otmp){
                if(otmp->olet == FOOD_SYM && !otmp->unpaid)
                        tmp += objects[otmp->otyp].nutrition;
                otmp = otmp->nobj;
        }
        return((tmp <= 0) ? 1 : tmp);
}

int
shkcatch(struct obj *obj)
{
        struct monst *shkp = shopkeeper;

        if(u.uinshop && shkp && !shkp->mfroz && !shkp->msleep &&
            u.dx && u.dy &&
            inroom(u.ux+u.dx, u.uy+u.dy) + 1 == u.uinshop &&
            shkp->mx == ESHK(shkp)->shk.x && shkp->my == ESHK(shkp)->shk.y &&
            u.ux == ESHK(shkp)->shd.x && u.uy == ESHK(shkp)->shd.y) {
                pline("%s nimbly catches the %s.", Monnam(shkp), xname(obj));
                obj->nobj = shkp->minvent;
                shkp->minvent = obj;
                return(1);
        }
        return(0);
}

/*
 * shk_move: return 1: he moved  0: he didnt  -1: let m_move do it
 */
int
shk_move(struct monst *shkp)
{
        struct monst *mtmp;
        struct permonst *mdat = shkp->data;
        xchar gx,gy,omx,omy,nx,ny,nix,niy;
        schar appr,i;
        int udist;
        int z;
        schar shkroom,chi,chcnt,cnt;
        boolean uondoor, satdoor, avoid, badinv;
        coord poss[9];
        int info[9];
        struct obj *ib = 0;

        omx = shkp->mx;
        omy = shkp->my;

        if((udist = dist(omx,omy)) < 3) {
                if(ANGRY(shkp)) {
                        (void) hitu(shkp, d(mdat->damn, mdat->damd)+1);
                        return(0);
                }
                if(ESHK(shkp)->following) {
                        if(strncmp(ESHK(shkp)->customer, plname, PL_NSIZ)){
                                pline("Hello %s! I was looking for %s.",
                                        plname, ESHK(shkp)->customer);
                                ESHK(shkp)->following = 0;
                                return(0);
                        }
                        if(!ESHK(shkp)->robbed) {       /* impossible? */
                                ESHK(shkp)->following = 0;
                                return(0);
                        }
                        if(moves > followmsg+4) {
                                pline("Hello %s! Didn't you forget to pay?",
                                        plname);
                                followmsg = moves;
                        }
                        if(udist < 2)
                                return(0);
                }
        }

        shkroom = inroom(omx,omy);
        appr = 1;
        gx = ESHK(shkp)->shk.x;
        gy = ESHK(shkp)->shk.y;
        satdoor = (gx == omx && gy == omy);
        if(ESHK(shkp)->following || ((z = holetime()) >= 0 && z*z <= udist)){
                gx = u.ux;
                gy = u.uy;
                if(shkroom < 0 || shkroom != inroom(u.ux,u.uy))
                    if(udist > 4)
                        return(-1);     /* leave it to m_move */
        } else if(ANGRY(shkp)) {
                long saveBlind = Blind;
                Blind = 0;
                if(shkp->mcansee && !Invis && cansee(omx,omy)) {
                        gx = u.ux;
                        gy = u.uy;
                }
                Blind = saveBlind;
                avoid = FALSE;
        } else {
#define GDIST(x,y)      ((x-gx)*(x-gx)+(y-gy)*(y-gy))
                if(Invis)
                  avoid = FALSE;
                else {
                  uondoor = (u.ux == ESHK(shkp)->shd.x &&
                                u.uy == ESHK(shkp)->shd.y);
                  if(uondoor) {
                    if(ESHK(shkp)->billct)
                        pline("Hello %s! Will you please pay before leaving?",
                                plname);
                    badinv = (carrying(PICK_AXE) || carrying(ICE_BOX));
                    if(satdoor && badinv)
                        return(0);
                    avoid = !badinv;
                  } else {
                    avoid = (u.uinshop && dist(gx,gy) > 8);
                    badinv = FALSE;
                  }

                  if(((!ESHK(shkp)->robbed && !ESHK(shkp)->billct) || avoid)
                        && GDIST(omx,omy) < 3){
                        if(!badinv && !online(omx,omy))
                                return(0);
                        if(satdoor)
                                appr = gx = gy = 0;
                  }
                }
        }
        if(omx == gx && omy == gy)
                return(0);
        if(shkp->mconf) {
                avoid = FALSE;
                appr = 0;
        }
        nix = omx;
        niy = omy;
        cnt = mfndpos(shkp,poss,info,ALLOW_SSM);
        if(avoid && uondoor) {          /* perhaps we cannot avoid him */
                for(i=0; i<cnt; i++)
                        if(!(info[(int)i] & NOTONL)) goto notonl_ok;
                avoid = FALSE;
        notonl_ok:
                ;
        }
        chi = -1;
        chcnt = 0;
        for(i=0; i<cnt; i++){
                nx = poss[(int)i].x;
                ny = poss[(int)i].y;
                if(levl[(int)nx][(int)ny].typ == ROOM
                || shkroom != ESHK(shkp)->shoproom
                || ESHK(shkp)->following) {
#ifdef STUPID
                    /* cater for stupid compilers */
                    int zz;
#endif /* STUPID */
                    if(uondoor && (ib = sobj_at(ICE_BOX, nx, ny))) {
                        nix = nx; niy = ny; chi = i; break;
                    }
                    if(avoid && (info[(int)i] & NOTONL))
                        continue;
                    if((!appr && !rn2(++chcnt)) ||
#ifdef STUPID
                        (appr && (zz = GDIST(nix,niy)) && zz > GDIST(nx,ny))
#else
                        (appr && GDIST(nx,ny) < GDIST(nix,niy))
#endif /* STUPID */
                        ) {
                            nix = nx;
                            niy = ny;
                            chi = i;
                    }
                }
        }
        if(nix != omx || niy != omy){
                if(info[(int)chi] & ALLOW_M){
                        mtmp = m_at(nix,niy);
                        if(hitmm(shkp,mtmp) == 1 && rn2(3) &&
                           hitmm(mtmp,shkp) == 2) return(2);
                        return(0);
                } else if(info[(int)chi] & ALLOW_U){
                        (void) hitu(shkp, d(mdat->damn, mdat->damd)+1);
                        return(0);
                }
                shkp->mx = nix;
                shkp->my = niy;
                pmon(shkp);
                if(ib) {
                        freeobj(ib);
                        mpickobj(shkp, ib);
                }
                return(1);
        }
        return(0);
}

/* He is digging in the shop. */
void
shopdig(int fall)
{
    if(!fall) {
        if(u.utraptype == TT_PIT)
            pline("\"Be careful, sir, or you might fall through the floor.\"");
        else
            pline("\"Please, do not damage the floor here.\"");
    } else if(dist(shopkeeper->mx, shopkeeper->my) < 3) {
        struct obj *obj, *obj2;

        pline("%s grabs your backpack!", shkname(shopkeeper));
        for(obj = invent; obj; obj = obj2) {
                obj2 = obj->nobj;
                if(obj->owornmask) continue;
                freeinv(obj);
                obj->nobj = shopkeeper->minvent;
                shopkeeper->minvent = obj;
                if(obj->unpaid)
                        subfrombill(obj);
        }
    }
}
#endif /* QUEST */

int
online(int x, int y)
{
        return(x==u.ux || y==u.uy ||
                (x-u.ux)*(x-u.ux) == (y-u.uy)*(y-u.uy));
}

/* Does this monster follow me downstairs? */
int
follower(struct monst *mtmp)
{
        return( mtmp->mtame || strchr("1TVWZi&, ", mtmp->data->mlet)
#ifndef QUEST
                || (mtmp->isshk && ESHK(mtmp)->following)
#endif /* QUEST */
                );
}