text: /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
  /* hack.vault.c - version 1.0.2 */
  
  #include	"hack.h"
  #ifdef QUEST
  setgd(/* mtmp */) /* struct monst *mtmp; */ {}
  gd_move() { return(2); }
  gddead(mtmp) struct monst *mtmp; {}
  replgd(mtmp,mtmp2) struct monst *mtmp, *mtmp2; {}
  invault(){}
  
  #else
  
  
  #include "def.mkroom.h"
  extern struct monst *makemon();
  #define	FCSIZ	(ROWNO+COLNO)
  struct fakecorridor {
  	xchar fx,fy,ftyp;
  };
  
  struct egd {
  	int fcbeg, fcend;	/* fcend: first unused pos */
  	xchar gdx, gdy;		/* goal of guard's walk */
  	unsigned gddone:1;
  	struct fakecorridor fakecorr[FCSIZ];
  };
  
  static struct permonst pm_guard =
  	{ "guard", '@', 12, 12, -1, 4, 10, sizeof(struct egd) };
  
  static struct monst *guard;
  static int gdlevel;
  #define	EGD	((struct egd *)(&(guard->mextra[0])))
  
  static
  restfakecorr()
  {
  	register fcx,fcy,fcbeg;
  	register struct rm *crm;
  
  	while((fcbeg = EGD->fcbeg) < EGD->fcend) {
  		fcx = EGD->fakecorr[fcbeg].fx;
  		fcy = EGD->fakecorr[fcbeg].fy;
  		if((u.ux == fcx && u.uy == fcy) || cansee(fcx,fcy) ||
  		   m_at(fcx,fcy))
  			return;
  		crm = &levl[fcx][fcy];
  		crm->typ = EGD->fakecorr[fcbeg].ftyp;
  		if(!crm->typ) crm->seen = 0;
  		newsym(fcx,fcy);
  		EGD->fcbeg++;
  	}
  	/* it seems he left the corridor - let the guard disappear */
  	mondead(guard);
  	guard = 0;
  }
  
  static
  goldincorridor()
  {
  	register int fci;
  
  	for(fci = EGD->fcbeg; fci < EGD->fcend; fci++)
  		if(g_at(EGD->fakecorr[fci].fx, EGD->fakecorr[fci].fy))
  			return(1);
  	return(0);
  }
  
  setgd(){
  register struct monst *mtmp;
  	for(mtmp = fmon; mtmp; mtmp = mtmp->nmon) if(mtmp->isgd){
  		guard = mtmp;
  		gdlevel = dlevel;
  		return;
  	}
  	guard = 0;
  }
  
  invault(){
  register tmp = inroom(u.ux, u.uy);
      if(tmp < 0 || rooms[tmp].rtype != VAULT) {
  	u.uinvault = 0;
  	return;
      }
      if(++u.uinvault % 50 == 0 && (!guard || gdlevel != dlevel)) {
  	char buf[BUFSZ];
  	register x,y,dd,gx,gy;
  
  	/* first find the goal for the guard */
  	for(dd = 1; (dd < ROWNO || dd < COLNO); dd++) {
  	  for(y = u.uy-dd; y <= u.uy+dd; y++) {
  	    if(y < 0 || y > ROWNO-1) continue;
  	    for(x = u.ux-dd; x <= u.ux+dd; x++) {
  	      if(y != u.uy-dd && y != u.uy+dd && x != u.ux-dd)
  		x = u.ux+dd;
  	      if(x < 0 || x > COLNO-1) continue;
  	      if(levl[x][y].typ == CORR) goto fnd;
  	    }
  	  }
  	}
  	impossible("Not a single corridor on this level??");
  	tele();
  	return;
  fnd:
  	gx = x; gy = y;
  
  	/* next find a good place for a door in the wall */
  	x = u.ux; y = u.uy;
  	while(levl[x][y].typ == ROOM) {
  		register int dx,dy;
  
  		dx = (gx > x) ? 1 : (gx < x) ? -1 : 0;
  		dy = (gy > y) ? 1 : (gy < y) ? -1 : 0;
  		if(abs(gx-x) >= abs(gy-y))
  			x += dx;
  		else
  			y += dy;
  	}
  
  	/* make something interesting happen */
  	if(!(guard = makemon(&pm_guard,x,y))) return;
  	guard->isgd = guard->mpeaceful = 1;
  	EGD->gddone = 0;
  	gdlevel = dlevel;
  	if(!cansee(guard->mx, guard->my)) {
  		mondead(guard);
  		guard = 0;
  		return;
  	}
  
  	pline("Suddenly one of the Vault's guards enters!");
  	pmon(guard);
  	do {
  		pline("\"Hello stranger, who are you?\" - ");
  		getlin(buf);
  	} while (!letter(buf[0]));
  
  	if(!strcmp(buf, "Croesus") || !strcmp(buf, "Kroisos")) {
  		pline("\"Oh, yes - of course. Sorry to have disturbed you.\"");
  		mondead(guard);
  		guard = 0;
  		return;
  	}
  	clrlin();
  	pline("\"I don't know you.\"");
  	if(!u.ugold)
  	    pline("\"Please follow me.\"");
  	else {
  	    pline("\"Most likely all that gold was stolen from this vault.\"");
  	    pline("\"Please drop your gold (say d$ ) and follow me.\"");
  	}
  	EGD->gdx = gx;
  	EGD->gdy = gy;
  	EGD->fcbeg = 0;
  	EGD->fakecorr[0].fx = x;
  	EGD->fakecorr[0].fy = y;
  	EGD->fakecorr[0].ftyp = levl[x][y].typ;
  	levl[x][y].typ = DOOR;
  	EGD->fcend = 1;
      }
  }
  
  gd_move(){
  register int x,y,dx,dy,gx,gy,nx,ny,typ;
  register struct fakecorridor *fcp;
  register struct rm *crm;
  	if(!guard || gdlevel != dlevel){
  		impossible("Where is the guard?");
  		return(2);	/* died */
  	}
  	if(u.ugold || goldincorridor())
  		return(0);	/* didnt move */
  	if(dist(guard->mx,guard->my) > 1 || EGD->gddone) {
  		restfakecorr();
  		return(0);	/* didnt move */
  	}
  	x = guard->mx;
  	y = guard->my;
  	/* look around (hor & vert only) for accessible places */
  	for(nx = x-1; nx <= x+1; nx++) for(ny = y-1; ny <= y+1; ny++) {
  	    if(nx == x || ny == y) if(nx != x || ny != y)
  	    if(isok(nx,ny))
  	    if(!IS_WALL(typ = (crm = &levl[nx][ny])->typ) && typ != POOL) {
  		register int i;
  		for(i = EGD->fcbeg; i < EGD->fcend; i++)
  			if(EGD->fakecorr[i].fx == nx &&
  			   EGD->fakecorr[i].fy == ny)
  				goto nextnxy;
  		if((i = inroom(nx,ny)) >= 0 && rooms[i].rtype == VAULT)
  			goto nextnxy;
  		/* seems we found a good place to leave him alone */
  		EGD->gddone = 1;
  		if(ACCESSIBLE(typ)) goto newpos;
  		crm->typ = (typ == SCORR) ? CORR : DOOR;
  		goto proceed;
  	    }
      nextnxy:	;
  	}
  	nx = x;
  	ny = y;
  	gx = EGD->gdx;
  	gy = EGD->gdy;
  	dx = (gx > x) ? 1 : (gx < x) ? -1 : 0;
  	dy = (gy > y) ? 1 : (gy < y) ? -1 : 0;
  	if(abs(gx-x) >= abs(gy-y)) nx += dx; else ny += dy;
  
  	while((typ = (crm = &levl[nx][ny])->typ) != 0) {
  	/* in view of the above we must have IS_WALL(typ) or typ == POOL */
  	/* must be a wall here */
  		if(isok(nx+nx-x,ny+ny-y) && typ != POOL &&
  		    ZAP_POS(levl[nx+nx-x][ny+ny-y].typ)){
  			crm->typ = DOOR;
  			goto proceed;
  		}
  		if(dy && nx != x) {
  			nx = x; ny = y+dy;
  			continue;
  		}
  		if(dx && ny != y) {
  			ny = y; nx = x+dx; dy = 0;
  			continue;
  		}
  		/* I don't like this, but ... */
  		crm->typ = DOOR;
  		goto proceed;
  	}
  	crm->typ = CORR;
  proceed:
  	if(cansee(nx,ny)) {
  		mnewsym(nx,ny);
  		prl(nx,ny);
  	}
  	fcp = &(EGD->fakecorr[EGD->fcend]);
  	if(EGD->fcend++ == FCSIZ) panic("fakecorr overflow");
  	fcp->fx = nx;
  	fcp->fy = ny;
  	fcp->ftyp = typ;
  newpos:
  	if(EGD->gddone) nx = ny = 0;
  	guard->mx = nx;
  	guard->my = ny;
  	pmon(guard);
  	restfakecorr();
  	return(1);
  }
  
  gddead(){
  	guard = 0;
  }
  
  replgd(mtmp,mtmp2)
  register struct monst *mtmp, *mtmp2;
  {
  	if(mtmp == guard)
  		guard = mtmp2;
  }
  
  #endif QUEST
  