/*
 *	Device independant TTY interface for JOE
 *	Copyright
 *		(C) 1992 Joseph H. Allen
 *
 *	This file is part of JOE (Joe's Own Editor)
 */
#include "config.h"
#include "types.h"

#include <ctype.h>
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif

#include "bw.h"
#include "blocks.h"
#include "scrn.h"
#include "termcap.h"
#include "utils.h"

int skiptop = 0;
int lines = 0;
int columns = 0;

extern int mid;

/* How to display characters (especially the control ones) */
/* here are characters ... */
unsigned char xlatc[256] = {
	 64,  65,  66,  67,  68,  69,  70,  71,			/*   8 */
	 72,  73,  74,  75,  76,  77,  78,  79,			/*  16 */
	 80,  81,  82,  83,  84,  85,  86,  87,			/*  24 */
	 88,  89,  90,  91,  92,  93,  94,  95,			/*  32 */
	 32,  33,  34,  35,  36,  37,  38,  39,			/*  40 */
	 40,  41,  42,  43,  44,  45,  46,  47,			/*  48 */
	 48,  49,  50,  51,  52,  53,  54,  55,			/*  56 */
	 56,  57,  58,  59,  60,  61,  62,  63,			/*  64 */

	 64,  65,  66,  67,  68,  69,  70,  71,			/*  72 */
	 72,  73,  74,  75,  76,  77,  78,  79,			/*  80 */
	 80,  81,  82,  83,  84,  85,  86,  87,			/*  88 */
	 88,  89,  90,  91,  92,  93,  94,  95,			/*  96 */
	 96,  97,  98,  99, 100, 101, 102, 103,			/* 104 */
	104, 105, 106, 107, 108, 109, 110, 111,			/* 112 */
	112, 113, 114, 115, 116, 117, 118, 119,			/* 120 */
	120, 121, 122, 123, 124, 125, 126,  63,			/* 128 */

	 64,  65,  66,  67,  68,  69,  70,  71,			/* 136 */
	 72,  73,  74,  75,  76,  77,  78,  79,			/* 144 */
	 80,  81,  82,  83,  84,  85,  86,  87,			/* 152 */
	 88,  89,  90,  91,  92,  93,  94,  95,			/* 160 */
	 32,  33,  34,  35,  36,  37,  38,  39,			/* 168 */
	 40,  41,  42,  43,  44,  45,  46,  47,			/* 176 */
	 48,  49,  50,  51,  52,  53,  54,  55,			/* 184 */
	 56,  57,  58,  59,  60,  61,  62,  63,			/* 192 */

	 64,  65,  66,  67,  68,  69,  70,  71,			/* 200 */
	 72,  73,  74,  75,  76,  77,  78,  79,			/* 208 */
	 80,  81,  82,  83,  84,  85,  86,  87,			/* 216 */
	 88,  89,  90,  91,  92,  93,  94,  95,			/* 224 */
	 96,  97,  98,  99, 100, 101, 102, 103,			/* 232 */
	104, 105, 106, 107, 108, 109, 110, 111,			/* 240 */
	112, 113, 114, 115, 116, 117, 118, 119,			/* 248 */
	120, 121, 122, 123, 124, 125, 126,  63			/* 256 */
};
/* ... and here their attributes */ 
unsigned xlata[256] = {
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*   4 */
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*   8 */
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*  12 */
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*  16 */
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*  20 */
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*  24 */
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*  28 */
	UNDERLINE, UNDERLINE, UNDERLINE, UNDERLINE,		/*  32 */
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,		/*  48 */
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,		/*  64 */
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,		/*  80 */
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,		/*  96 */
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,		/* 112 */
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, UNDERLINE,	/* 128 */

	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 130 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 132 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 134 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 136 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 138 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 140 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 142 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 144 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 146 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 148 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 150 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 152 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 154 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 156 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 158 */
	INVERSE + UNDERLINE, INVERSE + UNDERLINE,		/* 160 */

	INVERSE, INVERSE, INVERSE, INVERSE,			/* 164 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 168 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 172 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 176 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 180 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 184 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 188 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 192 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 196 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 200 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 204 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 208 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 212 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 216 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 220 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 224 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 228 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 232 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 236 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 240 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 244 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 248 */
	INVERSE, INVERSE, INVERSE, INVERSE,			/* 252 */
	INVERSE, INVERSE, INVERSE, INVERSE + UNDERLINE		/* 256 */
};

void xlat(int *attr, unsigned char *c)
{
	if(isprint(*c) || (dspasis && *c > 128))
		*attr = 0;
	else {
		*attr = xlata[*c];
		*c = xlatc[*c];
	}
}

/* Set attributes */

int attr(SCRN *t, int c)
{
	int e;

	c &= ~255;
	e = (t->attrib & ~c);
	if (e) {		/* If any attribute go off, switch them all off: fixes bug on PCs */
		if (t->me)
			texec(t->cap, t->me, 1, 0, 0, 0, 0);
		else {
			if (t->ue)
				texec(t->cap, t->ue, 1, 0, 0, 0, 0);
			if (t->se)
				texec(t->cap, t->se, 1, 0, 0, 0, 0);
		}
		t->attrib = 0;
	}
	e = (c & ~t->attrib);
	if (e & INVERSE) {
		if (t->mr)
			texec(t->cap, t->mr, 1, 0, 0, 0, 0);
		else if (t->so)
			texec(t->cap, t->so, 1, 0, 0, 0, 0);
	}
	if (e & UNDERLINE)
		if (t->us)
			texec(t->cap, t->us, 1, 0, 0, 0, 0);
	if (e & BLINK)
		if (t->mb)
			texec(t->cap, t->mb, 1, 0, 0, 0, 0);
	if (e & BOLD)
		if (t->md)
			texec(t->cap, t->md, 1, 0, 0, 0, 0);
	if (e & DIM)
		if (t->mh)
			texec(t->cap, t->mh, 1, 0, 0, 0, 0);
	t->attrib = c;
	return 0;
}

/* Set scrolling region */

static void setregn(SCRN *t, int top, int bot)
{
	if (!t->cs) {
		t->top = top;
		t->bot = bot;
		return;
	}
	if (t->top != top || t->bot != bot) {
		t->top = top;
		t->bot = bot;
		texec(t->cap, t->cs, 1, top, bot - 1, 0, 0);
		t->x = -1;
		t->y = -1;
	}
}

/* Enter insert mode */

static void setins(SCRN *t, int x)
{
	if (t->ins != 1 && t->im) {
		t->ins = 1;
		texec(t->cap, t->im, 1, x, 0, 0, 0);
	}
}

/* Exit insert mode */

int clrins(SCRN *t)
{
	if (t->ins != 0) {
		texec(t->cap, t->ei, 1, 0, 0, 0, 0);
		t->ins = 0;
	}
	return 0;
}

/* Erase from given screen coordinate to end of line */

int eraeol(SCRN *t, int x, int y)
{
	int *s, *ss;
	int w = t->co - x - 1;	/* Don't worry about last column */

	if (w <= 0)
		return 0;
	s = t->scrn + y * t->co + x;
	ss = s + w;
	do {
		if (*--ss != ' ') {
			++ss;
			break;
		}
	} while (ss != s);
	if ((ss - s > 3 || s[w] != ' ') && t->ce) {
		cpos(t, x, y);
		attr(t, 0);
		texec(t->cap, t->ce, 1, 0, 0, 0, 0);
		msetI(s, ' ', w);
	} else if (s != ss) {
		if (t->ins)
			clrins(t);
		if (t->x != x || t->y != y)
			cpos(t, x, y);
		if (t->attrib)
			attr(t, 0);
		while (s != ss) {
			*s = ' ';
			ttputc(' ');
			++t->x;
			++s;
		}
	}
	return 0;
}

/* As above but useable in insert mode */
/* The cursor position must already be correct */

static void outatri(SCRN *t, int x, int y, int c)
{
	unsigned char ch;

	if (c == -1)
		c = ' ';
	ch = c;
	c -= ch;
	if (c != t->attrib)
		attr(t, c);
	if (t->haz && ch == '~')
		ch = '\\';
	ttputc(ch);
	++t->x;
}

static void out(char *t, char c)
{
	ttputc(c);
}

SCRN *nopen(CAP *cap)
{
	SCRN *t = (SCRN *) joe_malloc(sizeof(SCRN));
	int x, y;

	ttopen();

	t->cap = cap;
	setcap(cap, baud, out, NULL);

	t->li = getnum(t->cap, "li");
	if (t->li < 1)
		t->li = 24;
	t->co = getnum(t->cap, "co");
	if (t->co < 2)
		t->co = 80;
	x = y = 0;
	ttgtsz(&x, &y);
	if (x > 7 && y > 3) {
		t->li = y;
		t->co = x;
	}

	t->haz = getflag(t->cap, "hz");
	t->os = getflag(t->cap, "os");
	t->eo = getflag(t->cap, "eo");
	if (getflag(t->cap, "hc"))
		t->os = 1;
	if (t->os || getflag(t->cap, "ul"))
		t->ul = 1;
	else
		t->ul = 0;

	t->xn = getflag(t->cap, "xn");
	t->am = getflag(t->cap, "am");

	t->ti = jgetstr(t->cap, "ti");
	t->cl = jgetstr(t->cap, "cl");
	t->cd = jgetstr(t->cap, "cd");

	t->te = jgetstr(t->cap, "te");

	t->mb = NULL;
	t->md = NULL;
	t->mh = NULL;
	t->mr = NULL;
	t->avattr = 0;
	if (!(t->me = jgetstr(t->cap, "me")))
		goto oops;
	if ((t->mb = jgetstr(t->cap, "mb")))
		t->avattr |= BLINK;
	if ((t->md = jgetstr(t->cap, "md")))
		t->avattr |= BOLD;
	if ((t->mh = jgetstr(t->cap, "mh")))
		t->avattr |= DIM;
	if ((t->mr = jgetstr(t->cap, "mr")))
		t->avattr |= INVERSE;
      oops:

	t->so = NULL;
	t->se = NULL;
	if (getnum(t->cap, "sg") <= 0 && !t->mr && jgetstr(t->cap, "se")) {
		if ((t->so = jgetstr(t->cap, "so")) != NULL)
			t->avattr |= INVERSE;
		t->se = jgetstr(t->cap, "se");
	}
	if (getflag(t->cap, "xs") || getflag(t->cap, "xt"))
		t->so = NULL;

	t->us = NULL;
	t->ue = NULL;
	if (getnum(t->cap, "ug") <= 0 && jgetstr(t->cap, "ue")) {
		if ((t->us = jgetstr(t->cap, "us")) != NULL)
			t->avattr |= UNDERLINE;
		t->ue = jgetstr(t->cap, "ue");
	}

	if (!(t->uc = jgetstr(t->cap, "uc")))
		if (t->ul)
			t->uc = "_";
	if (t->uc)
		t->avattr |= UNDERLINE;

	t->ms = getflag(t->cap, "ms");

	t->da = getflag(t->cap, "da");
	t->db = getflag(t->cap, "db");
	t->cs = jgetstr(t->cap, "cs");
	t->rr = getflag(t->cap, "rr");
	t->sf = jgetstr(t->cap, "sf");
	t->sr = jgetstr(t->cap, "sr");
	t->SF = jgetstr(t->cap, "SF");
	t->SR = jgetstr(t->cap, "SR");
	t->al = jgetstr(t->cap, "al");
	t->dl = jgetstr(t->cap, "dl");
	t->AL = jgetstr(t->cap, "AL");
	t->DL = jgetstr(t->cap, "DL");
	if (!getflag(t->cap, "ns") && !t->sf)
		t->sf = "\12";

	if (!getflag(t->cap, "in") && baud < 38400) {
		t->dc = jgetstr(t->cap, "dc");
		t->DC = jgetstr(t->cap, "DC");
		t->dm = jgetstr(t->cap, "dm");
		t->ed = jgetstr(t->cap, "ed");

		t->im = jgetstr(t->cap, "im");
		t->ei = jgetstr(t->cap, "ei");
		t->ic = jgetstr(t->cap, "ic");
		t->IC = jgetstr(t->cap, "IC");
		t->ip = jgetstr(t->cap, "ip");
		t->mi = getflag(t->cap, "mi");
	} else {
		t->dm = NULL;
		t->dc = NULL;
		t->DC = NULL;
		t->ed = NULL;
		t->im = NULL;
		t->ic = NULL;
		t->IC = NULL;
		t->ip = NULL;
		t->ei = NULL;
		t->mi = 1;
	}

	t->bs = NULL;
	if (jgetstr(t->cap, "bc"))
		t->bs = jgetstr(t->cap, "bc");
	else if (jgetstr(t->cap, "le"))
		t->bs = jgetstr(t->cap, "le");
	if (getflag(t->cap, "bs"))
		t->bs = "\10";

	t->cbs = tcost(t->cap, t->bs, 1, 2, 2, 0, 0);

	t->lf = "\12";
	if (jgetstr(t->cap, "do"))
		t->lf = jgetstr(t->cap, "do");
	t->clf = tcost(t->cap, t->lf, 1, 2, 2, 0, 0);

	t->up = jgetstr(t->cap, "up");
	t->cup = tcost(t->cap, t->up, 1, 2, 2, 0, 0);

	t->nd = jgetstr(t->cap, "nd");

	t->tw = 8;
	if (getnum(t->cap, "it") > 0)
		t->tw = getnum(t->cap, "it");
	else if (getnum(t->cap, "tw") > 0)
		t->tw = getnum(t->cap, "tw");

	if (!(t->ta = jgetstr(t->cap, "ta")))
		if (getflag(t->cap, "pt"))
			t->ta = "\11";
	t->bt = jgetstr(t->cap, "bt");
	if (getflag(t->cap, "xt")) {
		t->ta = NULL;
		t->bt = NULL;
	}

	t->cta = tcost(t->cap, t->ta, 1, 2, 2, 0, 0);
	t->cbt = tcost(t->cap, t->bt, 1, 2, 2, 0, 0);

	t->ho = jgetstr(t->cap, "ho");
	t->cho = tcost(t->cap, t->ho, 1, 2, 2, 0, 0);
	t->ll = jgetstr(t->cap, "ll");
	t->cll = tcost(t->cap, t->ll, 1, 2, 2, 0, 0);

	t->cr = "\15";
	if (jgetstr(t->cap, "cr"))
		t->cr = jgetstr(t->cap, "cr");
	if (getflag(t->cap, "nc") || getflag(t->cap, "xr"))
		t->cr = NULL;
	t->ccr = tcost(t->cap, t->cr, 1, 2, 2, 0, 0);

	t->cRI = tcost(t->cap, t->RI = jgetstr(t->cap, "RI"), 1, 2, 2, 0, 0);
	t->cLE = tcost(t->cap, t->LE = jgetstr(t->cap, "LE"), 1, 2, 2, 0, 0);
	t->cUP = tcost(t->cap, t->UP = jgetstr(t->cap, "UP"), 1, 2, 2, 0, 0);
	t->cDO = tcost(t->cap, t->DO = jgetstr(t->cap, "DO"), 1, 2, 2, 0, 0);
	t->cch = tcost(t->cap, t->ch = jgetstr(t->cap, "ch"), 1, 2, 2, 0, 0);
	t->ccv = tcost(t->cap, t->cv = jgetstr(t->cap, "cv"), 1, 2, 2, 0, 0);
	t->ccV = tcost(t->cap, t->cV = jgetstr(t->cap, "cV"), 1, 2, 2, 0, 0);
	t->ccm = tcost(t->cap, t->cm = jgetstr(t->cap, "cm"), 1, 2, 2, 0, 0);

	t->cce = tcost(t->cap, t->ce = jgetstr(t->cap, "ce"), 1, 2, 2, 0, 0);

/* Make sure terminal can do absolute positioning */
	if (t->cm)
		goto ok;
	if (t->ch && t->cv)
		goto ok;
	if (t->ho && (t->lf || t->DO || t->cv))
		goto ok;
	if (t->ll && (t->up || t->UP || t->cv))
		goto ok;
	if (t->cr && t->cv)
		goto ok;
	leave = 1;
	ttclose();
	signrm();
	fprintf(stderr, "Sorry, your terminal can't do absolute cursor positioning.\nIt's broken\n");
	return NULL;
      ok:

/* Determine if we can scroll */
	if (((t->sr || t->SR) && (t->sf || t->SF) && t->cs) || ((t->al || t->AL) && (t->dl || t->DL)))
		t->scroll = 1;
	else {
		t->scroll = 0;
		if (baud < 38400)
			mid = 1;
	}

/* Determine if we can ins/del within lines */
	if ((t->im || t->ic || t->IC) && (t->dc || t->DC))
		t->insdel = 1;
	else
		t->insdel = 0;

/* Adjust for high baud rates */
	if (baud >= 38400) {
		t->scroll = 0;
		t->insdel = 0;
	}

/* Send out terminal initialization string */
	if (t->ti)
		texec(t->cap, t->ti, 1, 0, 0, 0, 0);
	if (!skiptop && t->cl)
		texec(t->cap, t->cl, 1, 0, 0, 0, 0);

/* Initialize variable screen size dependant vars */
	t->scrn = NULL;
	t->sary = NULL;
	t->updtab = NULL;
	t->compose = NULL;
	t->ofst = NULL;
	t->ary = NULL;
	t->htab = (struct hentry *) joe_malloc(256 * sizeof(struct hentry));

	nresize(t, t->co, t->li);

	return t;
}

/* Change size of screen */

void nresize(SCRN *t, int w, int h)
{
	if (h < 4)
		h = 4;
	if (w < 8)
		w = 8;
	t->li = h;
	t->co = w;
	if (t->sary)
		joe_free(t->sary);
	if (t->updtab)
		joe_free(t->updtab);
	if (t->scrn)
		joe_free(t->scrn);
	if (t->compose)
		joe_free(t->compose);
	if (t->ofst)
		joe_free(t->ofst);
	if (t->ary)
		joe_free(t->ary);
	t->scrn = (int *) joe_malloc(t->li * t->co * sizeof(int));
	t->sary = (int *) joe_calloc(t->li, sizeof(int));
	t->updtab = (int *) joe_malloc(t->li * sizeof(int));
	t->compose = (int *) joe_malloc(t->co * sizeof(int));
	t->ofst = (int *) joe_malloc(t->co * sizeof(int));
	t->ary = (struct hentry *) joe_malloc(t->co * sizeof(struct hentry));

	nredraw(t);
}

/* Calculate cost of positioning the cursor using only relative cursor
 * positioning functions: t->(lf, DO, up, UP, bs, LE, RI, ta, bt) and rewriting
 * characters (to move right)
 *
 * This doesn't use the am and bw capabilities although it probably could.
 */

static int relcost(register SCRN *t, register int x, register int y, register int ox, register int oy)
{
	int cost = 0;

/* If we don't know the cursor position, force use of absolute positioning */
	if (oy == -1 || ox == -1)
		return 10000;

/* First adjust row */
	if (y > oy) {
		int dist = y - oy;

		/* Have to go down */
		if (t->lf) {
			int mult = dist * t->clf;

			if (dist < 10 && t->cDO < mult)
				cost += t->cDO;
			else if (dist >= 10 && t->cDO + 1 < mult)
				cost += t->cDO + 1;
			else
				cost += mult;
		} else if (t->DO)
			if (dist < 10)
				cost += t->cDO;
			else
				cost += t->cDO + 1;
		else
			return 10000;
	} else if (y < oy) {
		int dist = oy - y;

		/* Have to go up */
		if (t->up) {
			int mult = dist * t->cup;

			if (dist < 10 && t->cUP < mult)
				cost += t->cUP;
			else if (dist >= 10 && t->cUP < mult)
				cost += t->cUP + 1;
			else
				cost += mult;
		} else if (t->UP)
			if (dist < 10)
				cost += t->cUP;
			else
				cost += t->cUP + 1;
		else
			return 10000;
	}

/* Now adjust column */

/* Use tabs */
	if (x > ox && t->ta) {
		int dist = x - ox;
		int ntabs = (dist + ox % t->tw) / t->tw;
		int cstunder = x % t->tw + t->cta * ntabs;
		int cstover;

		if (x + t->tw < t->co && t->bs)
			cstover = t->cbs * (t->tw - x % t->tw) + t->cta * (ntabs + 1);
		else
			cstover = 10000;
		if (dist < 10 && cstunder < t->cRI && cstunder < x - ox && cstover > cstunder)
			return cost + cstunder;
		else if (cstunder < t->cRI + 1 && cstunder < x - ox && cstover > cstunder)
			return cost + cstunder;
		else if (dist < 10 && cstover < t->cRI && cstover < x - ox)
			return cost + cstover;
		else if (cstover < t->cRI + 1 && cstover < x - ox)
			return cost + cstover;
	} else if (x < ox && t->bt) {
		int dist = ox - x;
		int ntabs = (dist + t->tw - ox % t->tw) / t->tw;
		int cstunder, cstover;

		if (t->bs)
			cstunder = t->cbt * ntabs + t->cbs * (t->tw - x % t->tw);
		else
			cstunder = 10000;
		if (x - t->tw >= 0)
			cstover = t->cbt * (ntabs + 1) + x % t->tw;
		else
			cstover = 10000;
		if (dist < 10 && cstunder < t->cLE && (t->bs ? cstunder < (ox - x) * t->cbs : 1)
		    && cstover > cstunder)
			return cost + cstunder;
		if (cstunder < t->cLE + 1 && (t->bs ? cstunder < (ox - x) * t->cbs : 1)
		    && cstover > cstunder)
			return cost + cstunder;
		else if (dist < 10 && cstover < t->cRI && (t->bs ? cstover < (ox - x) * t->cbs : 1))
			return cost + cstover;
		else if (cstover < t->cRI + 1 && (t->bs ? cstover < (ox - x) * t->cbs : 1))
			return cost + cstover;
	}

/* Use simple motions */
	if (x < ox) {
		int dist = ox - x;

		/* Have to go left */
		if (t->bs) {
			int mult = dist * t->cbs;

			if (t->cLE < mult && dist < 10)
				cost += t->cLE;
			else if (t->cLE + 1 < mult)
				cost += t->cLE + 1;
			else
				cost += mult;
		} else if (t->LE)
			cost += t->cLE;
		else
			return 10000;
	} else if (x > ox) {
		int dist = x - ox;

		/* Have to go right */
		/* Hmm.. this should take into account possible attribute changes */
		if (t->cRI < dist && dist < 10)
			cost += t->cRI;
		else if (t->cRI + 1 < dist)
			cost += t->cRI + 1;
		else
			cost += dist;
	}

	return cost;
}

/* Find optimal set of cursor positioning commands to move from the current
 * cursor row and column (either or both of which might be unknown) to the
 * given new row and column and execute them.
 */

static void cposs(register SCRN *t, register int x, register int y)
{
	register int bestcost, cost;
	int bestway;
	int hy;
	int hl;

/* Home y position is usually 0, but it is 'top' if we have scrolling region
 * relative addressing
 */
	if (t->rr) {
		hy = t->top;
		hl = t->bot - 1;
	} else {
		hy = 0;
		hl = t->li - 1;
	}

/* Assume best way is with only using relative cursor positioning */

	bestcost = relcost(t, x, y, t->x, t->y);
	bestway = 0;

/* Now check if combinations of absolute cursor positioning functions are
 * better (or necessary in case one or both cursor positions are unknown)
 */

	if (t->ccm < bestcost) {
		cost = tcost(t->cap, t->cm, 1, y, x, 0, 0);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 6;
		}
	}
	if (t->ccr < bestcost) {
		cost = relcost(t, x, y, 0, t->y) + t->ccr;
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 1;
		}
	}
	if (t->cho < bestcost) {
		cost = relcost(t, x, y, 0, hy) + t->cho;
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 2;
		}
	}
	if (t->cll < bestcost) {
		cost = relcost(t, x, y, 0, hl) + t->cll;
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 3;
		}
	}
	if (t->cch < bestcost && x != t->x) {
		cost = relcost(t, x, y, x, t->y) + tcost(t->cap, t->ch, 1, x, 0, 0, 0);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 4;
		}
	}
	if (t->ccv < bestcost && y != t->y) {
		cost = relcost(t, x, y, t->x, y) + tcost(t->cap, t->cv, 1, y, 0, 0, 0);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 5;
		}
	}
	if (t->ccV < bestcost) {
		cost = relcost(t, x, y, 0, y) + tcost(t->cap, t->cV, 1, y, 0, 0, 0);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 13;
		}
	}
	if (t->cch + t->ccv < bestcost && x != t->x && y != t->y) {
		cost = tcost(t->cap, t->cv, 1, y - hy, 0, 0, 0) + tcost(t->cap, t->ch, 1, x, 0, 0, 0);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 7;
		}
	}
	if (t->ccv + t->ccr < bestcost && y != t->y) {
		cost = tcost(t->cap, t->cv, 1, y, 0, 0, 0) + tcost(t->cap, t->cr, 1, 0, 0, 0, 0) + relcost(t, x, y, 0, y);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 8;
		}
	}
	if (t->cll + t->cch < bestcost) {
		cost = tcost(t->cap, t->ll, 1, 0, 0, 0, 0) + tcost(t->cap, t->ch, 1, x, 0, 0, 0) + relcost(t, x, y, x, hl);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 9;
		}
	}
	if (t->cll + t->ccv < bestcost) {
		cost = tcost(t->cap, t->ll, 1, 0, 0, 0, 0) + tcost(t->cap, t->cv, 1, y, 0, 0, 0) + relcost(t, x, y, 0, y);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 10;
		}
	}
	if (t->cho + t->cch < bestcost) {
		cost = tcost(t->cap, t->ho, 1, 0, 0, 0, 0) + tcost(t->cap, t->ch, 1, x, 0, 0, 0) + relcost(t, x, y, x, hy);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 11;
		}
	}
	if (t->cho + t->ccv < bestcost) {
		cost = tcost(t->cap, t->ho, 1, 0, 0, 0, 0) + tcost(t->cap, t->cv, 1, y, 0, 0, 0) + relcost(t, x, y, 0, y);
		if (cost < bestcost) {
			bestcost = cost;
			bestway = 12;
		}
	}

/* Do absolute cursor positioning if we don't know the cursor position or
 * if it is faster than doing only relative cursor positioning
 */

	switch (bestway) {
	case 1:
		texec(t->cap, t->cr, 1, 0, 0, 0, 0);
		t->x = 0;
		break;
	case 2:
		texec(t->cap, t->ho, 1, 0, 0, 0, 0);
		t->x = 0;
		t->y = hy;
		break;
	case 3:
		texec(t->cap, t->ll, 1, 0, 0, 0, 0);
		t->x = 0;
		t->y = hl;
		break;
	case 9:
		texec(t->cap, t->ll, 1, 0, 0, 0, 0);
		t->x = 0;
		t->y = hl;
		goto doch;
	case 11:
		texec(t->cap, t->ho, 1, 0, 0, 0, 0);
		t->x = 0;
		t->y = hy;
doch:
	case 4:
		texec(t->cap, t->ch, 1, x, 0, 0, 0);
		t->x = x;
		break;
	case 10:
		texec(t->cap, t->ll, 1, 0, 0, 0, 0);
		t->x = 0;
		t->y = hl;
		goto docv;
	case 12:
		texec(t->cap, t->ho, 1, 0, 0, 0, 0);
		t->x = 0;
		t->y = hy;
		goto docv;
	case 8:
		texec(t->cap, t->cr, 1, 0, 0, 0, 0);
		t->x = 0;
docv:
	case 5:
		texec(t->cap, t->cv, 1, y, 0, 0, 0);
		t->y = y;
		break;
	case 6:
		texec(t->cap, t->cm, 1, y, x, 0, 0);
		t->y = y;
		t->x = x;
		break;
	case 7:
		texec(t->cap, t->cv, 1, y, 0, 0, 0);
		t->y = y;
		texec(t->cap, t->ch, 1, x, 0, 0, 0);
		t->x = x;
		break;
	case 13:
		texec(t->cap, t->cV, 1, y, 0, 0, 0);
		t->y = y;
		t->x = 0;
		break;
	}

/* Use relative cursor position functions if we're not there yet */

/* First adjust row */
	if (y > t->y) {
		/* Have to go down */
		if (!t->lf || t->cDO < (y - t->y) * t->clf) {
			texec(t->cap, t->DO, 1, y - t->y, 0, 0, 0);
			t->y = y;
		} else
			while (y > t->y) {
				texec(t->cap, t->lf, 1, 0, 0, 0, 0);
				++t->y;
			}
	} else if (y < t->y) {
		/* Have to go up */
		if (!t->up || t->cUP < (t->y - y) * t->cup) {
			texec(t->cap, t->UP, 1, t->y - y, 0, 0, 0);
			t->y = y;
		} else
			while (y < t->y) {
				texec(t->cap, t->up, 1, 0, 0, 0, 0);
				--t->y;
			}
	}

/* Use tabs */
	if (x > t->x && t->ta) {
		int ntabs = (x - t->x + t->x % t->tw) / t->tw;
		int cstunder = x % t->tw + t->cta * ntabs;
		int cstover;

		if (x + t->tw < t->co && t->bs)
			cstover = t->cbs * (t->tw - x % t->tw) + t->cta * (ntabs + 1);
		else
			cstover = 10000;
		if (cstunder < t->cRI && cstunder < x - t->x && cstover > cstunder) {
			if (ntabs) {
				t->x = x - x % t->tw;
				do {
					texec(t->cap, t->ta, 1, 0, 0, 0, 0);
				} while (--ntabs);
			}
		} else if (cstover < t->cRI && cstover < x - t->x) {
			t->x = t->tw + x - x % t->tw;
			++ntabs;
			do {
				texec(t->cap, t->ta, 1, 0, 0, 0, 0);
			} while (--ntabs);
		}
	} else if (x < t->x && t->bt) {
		int ntabs = ((t->x + t->tw - 1) - (t->x + t->tw - 1) % t->tw - ((x + t->tw - 1) - (x + t->tw - 1) % t->tw)) / t->tw;
		int cstunder, cstover;

		if (t->bs)
			cstunder = t->cbt * ntabs + t->cbs * (t->tw - x % t->tw);
		else
			cstunder = 10000;
		if (x - t->tw >= 0)
			cstover = t->cbt * (ntabs + 1) + x % t->tw;
		else
			cstover = 10000;
		if (cstunder < t->cLE && (t->bs ? cstunder < (t->x - x) * t->cbs : 1)
		    && cstover > cstunder) {
			if (ntabs) {
				do {
					texec(t->cap, t->bt, 1, 0, 0, 0, 0);
				} while (--ntabs);
				t->x = x + t->tw - x % t->tw;
			}
		} else if (cstover < t->cRI && (t->bs ? cstover < (t->x - x) * t->cbs : 1)) {
			t->x = x - x % t->tw;
			++ntabs;
			do {
				texec(t->cap, t->bt, 1, 0, 0, 0, 0);
			} while (--ntabs);
		}
	}

/* Now adjust column */
	if (x < t->x) {
		/* Have to go left */
		if (!t->bs || t->cLE < (t->x - x) * t->cbs) {
			texec(t->cap, t->LE, 1, t->x - x, 0, 0, 0);
			t->x = x;
		} else
			while (x < t->x) {
				texec(t->cap, t->bs, 1, 0, 0, 0, 0);
				--t->x;
			}
	} else if (x > t->x) {
		/* Have to go right */
		/* Hmm.. this should take into account possible attribute changes */
		if (t->cRI < x - t->x) {
			texec(t->cap, t->RI, 1, x - t->x, 0, 0, 0);
			t->x = x;
		} else {
			int *s = t->scrn + t->x + t->y * t->co;

			if (t->ins)
				clrins(t);
			while (x > t->x) {
				int c = (0xFF & *s);
				int a = (0xFF00 & *s);

				if (a != t->attrib)
					attr(t, a);
				ttputc(c);
				++s;
				++t->x;
			}
		}
	}
}

int cpos(register SCRN *t, register int x, register int y)
{
	if (y == t->y) {
		if (x == t->x)
			return 0;
		if (x > t->x && x - t->x < 4 && !t->ins) {
			int *cs = t->scrn + t->x + t->co * t->y;

			if (t->ins)
				clrins(t);
			do {
				int c = (0xFF & *cs);
				int a = (0xFF00 & *cs);

				if (a != t->attrib)
					attr(t, a);
				ttputc(c);
				++cs;
				++t->x;
			} while (x != t->x);
			return 0;
		}
	}
	if (!t->ms && t->attrib & (INVERSE | UNDERLINE))
		attr(t, t->attrib & ~(INVERSE | UNDERLINE));
	if (y < t->top || y >= t->bot)
		setregn(t, 0, t->li);
	cposs(t, x, y);
	return 0;
}

static void doinschr(SCRN *t, int x, int y, int *s, int n)
{
	int a;

	if (x < 0) {
		s -= x;
		x = 0;
	}
	if (x >= t->co - 1 || n <= 0)
		return;
	if (t->im || t->ic || t->IC) {
		cpos(t, x, y);
		if ((n == 1 && t->ic) || !t->IC) {
			if (!t->ic)
				setins(t, x);
			for (a = 0; a != n; ++a) {
				texec(t->cap, t->ic, 1, x, 0, 0, 0);
				outatri(t, x + a, y, s[a]);
				texec(t->cap, t->ip, 1, x, 0, 0, 0);
			}
			if (!t->mi)
				clrins(t);
		} else {
			texec(t->cap, t->IC, 1, n, 0, 0, 0);
			for (a = 0; a != n; ++a)
				outatri(t, x + a, y, s[a]);
		}
	}
	mmove(t->scrn + x + t->co * y + n, t->scrn + x + t->co * y, (t->co - (x + n)) * sizeof(int));
	mmove(t->scrn + x + t->co * y, s, n * sizeof(int));
}

static void dodelchr(SCRN *t, int x, int y, int n)
{
	int a;

	if (x < 0)
		x = 0;
	if (!n || x >= t->co - 1)
		return;
	if (t->dc || t->DC) {
		cpos(t, x, y);
		texec(t->cap, t->dm, 1, x, 0, 0, 0);	/* Enter delete mode */
		if ((n == 1 && t->dc) || !t->DC)
			for (a = n; a; --a)
				texec(t->cap, t->dc, 1, x, 0, 0, 0);
		else
			texec(t->cap, t->DC, 1, n, 0, 0, 0);
		texec(t->cap, t->ed, 1, x, 0, 0, 0);	/* Exit delete mode */
	}
	mmove(t->scrn + t->co * y + x, t->scrn + t->co * y + x + n, (t->co - (x + n)) * sizeof(int));
	msetI(t->scrn + t->co * y + t->co - n, ' ', n);
}

/* Insert/Delete within line */

void magic(SCRN *t, int y, int *cs, int *s, int placex)
{
	struct hentry *htab = t->htab;
	int *ofst = t->ofst;
	int aryx = 1;
	int x;

	if (!(t->im || t->ic || t->IC) || !(t->dc || t->DC))
		return;
	mset(htab, 0, 256 * sizeof(struct hentry));

	msetI(ofst, 0, t->co);

/* Build hash table */
	for (x = 0; x != t->co - 1; ++x) {
		t->ary[aryx].next = htab[cs[x] & 255].next;
		t->ary[aryx].loc = x;
		++htab[cs[x] & 255].loc;
		htab[cs[x] & 255].next = aryx++;
	}

/* Build offset table */
	for (x = 0; x < t->co - 1;)
		if (htab[s[x] & 255].loc >= 15)
			ofst[x++] = t->co - 1;
		else {
			int aryy;
			int maxaryy;
			int maxlen = 0;
			int best = 0;
			int bestback = 0;
			int z;

			for (aryy = htab[s[x] & 255].next; aryy; aryy = t->ary[aryy].next) {
				int amnt, back;
				int tsfo = t->ary[aryy].loc - x;
				int cst = -abs(tsfo);
				int pre = 32;

				for (amnt = 0; x + amnt < t->co - 1 && x + tsfo + amnt < t->co - 1; ++amnt) {
					if (cs[x + tsfo + amnt] != s[x + amnt])
						break;
					else if ((s[x + amnt] & 255) != 32 || pre != 32)
						++cst;
					pre = s[x + amnt] & 255;
				}
				pre = 32;
				for (back = 0; back + x > 0 && back + tsfo + x > 0; --back) {
					if (cs[x + tsfo + back - 1] != s[x + back - 1])
						break;
					else if ((s[x + back - 1] & 255) != 32 || pre != 32)
						++cst;
					pre = s[x + back - 1] & 255;
				}
				if (cst > best) {
					maxaryy = aryy;
					maxlen = amnt;
					best = cst;
					bestback = back;
				}
			}
			if (!maxlen) {
				ofst[x] = t->co - 1;
				maxlen = 1;
			} else if (best < 2)
				for (z = 0; z != maxlen; ++z)
					ofst[x + z] = t->co - 1;
			else
				for (z = 0; z != maxlen - bestback; ++z)
					ofst[x + z + bestback] = t->ary[maxaryy].loc - x;
			x += maxlen;
		}

/* Apply scrolling commands */

	for (x = 0; x != t->co - 1; ++x) {
		int q = ofst[x];

		if (q && q != t->co - 1) {
			if (q > 0) {
				int z, fu;

				for (z = x; z != t->co - 1 && ofst[z] == q; ++z) ;
				while (s[x] == cs[x] && x < placex)
					++x;
				dodelchr(t, x, y, q);
				for (fu = x; fu != t->co - 1; ++fu)
					if (ofst[fu] != t->co - 1)
						ofst[fu] -= q;
				x = z - 1;
			} else {
				int z, fu;

				for (z = x; z != t->co - 1 && ofst[z] == q; ++z) ;
				while (s[x + q] == cs[x + q] && x - q < placex)
					++x;
				doinschr(t, x + q, y, s + x + q, -q);
				for (fu = x; fu != t->co - 1; ++fu)
					if (ofst[fu] != t->co - 1)
						ofst[fu] -= q;
				x = z - 1;
			}
		}
	}
}

static void doupscrl(SCRN *t, int top, int bot, int amnt)
{
	int a = amnt;

	if (!amnt)
		return;
	attr(t, 0);
	if (top == 0 && bot == t->li && (t->sf || t->SF)) {
		setregn(t, 0, t->li);
		cpos(t, 0, t->li - 1);
		if ((amnt == 1 && t->sf) || !t->SF)
			while (a--)
				texec(t->cap, t->sf, 1, t->li - 1, 0, 0, 0);
		else
			texec(t->cap, t->SF, a, a, 0, 0, 0);
		goto done;
	}
	if (bot == t->li && (t->dl || t->DL)) {
		setregn(t, 0, t->li);
		cpos(t, 0, top);
		if ((amnt == 1 && t->dl) || !t->DL)
			while (a--)
				texec(t->cap, t->dl, 1, top, 0, 0, 0);
		else
			texec(t->cap, t->DL, a, a, 0, 0, 0);
		goto done;
	}
	if (t->cs && (t->sf || t->SF)) {
		setregn(t, top, bot);
		cpos(t, 0, bot - 1);
		if ((amnt == 1 && t->sf) || !t->SF)
			while (a--)
				texec(t->cap, t->sf, 1, bot - 1, 0, 0, 0);
		else
			texec(t->cap, t->SF, a, a, 0, 0, 0);
		goto done;
	}
	if ((t->dl || t->DL) && (t->al || t->AL)) {
		cpos(t, 0, top);
		if ((amnt == 1 && t->dl) || !t->DL)
			while (a--)
				texec(t->cap, t->dl, 1, top, 0, 0, 0);
		else
			texec(t->cap, t->DL, a, a, 0, 0, 0);
		a = amnt;
		cpos(t, 0, bot - amnt);
		if ((amnt == 1 && t->al) || !t->AL)
			while (a--)
				texec(t->cap, t->al, 1, bot - amnt, 0, 0, 0);
		else
			texec(t->cap, t->AL, a, a, 0, 0, 0);
		goto done;
	}
	msetI(t->updtab + top, 1, bot - top);
	return;

      done:
	mmove(t->scrn + top * t->co, t->scrn + (top + amnt) * t->co, (bot - top - amnt) * t->co * sizeof(int));

	if (bot == t->li && t->db) {
		msetI(t->scrn + (t->li - amnt) * t->co, -1, amnt * t->co);
		msetI(t->updtab + t->li - amnt, 1, amnt);
	} else
		msetI(t->scrn + (bot - amnt) * t->co, ' ', amnt * t->co);
}

static void dodnscrl(SCRN *t, int top, int bot, int amnt)
{
	int a = amnt;

	if (!amnt)
		return;
	attr(t, 0);
	if (top == 0 && bot == t->li && (t->sr || t->SR)) {
		setregn(t, 0, t->li);
		cpos(t, 0, 0);
		if ((amnt == 1 && t->sr) || !t->SR)
			while (a--)
				texec(t->cap, t->sr, 1, 0, 0, 0, 0);
		else
			texec(t->cap, t->SR, a, a, 0, 0, 0);
		goto done;
	}
	if (bot == t->li && (t->al || t->AL)) {
		setregn(t, 0, t->li);
		cpos(t, 0, top);
		if ((amnt == 1 && t->al) || !t->AL)
			while (a--)
				texec(t->cap, t->al, 1, top, 0, 0, 0);
		else
			texec(t->cap, t->AL, a, a, 0, 0, 0);
		goto done;
	}
	if (t->cs && (t->sr || t->SR)) {
		setregn(t, top, bot);
		cpos(t, 0, top);
		if ((amnt == 1 && t->sr) || !t->SR)
			while (a--)
				texec(t->cap, t->sr, 1, top, 0, 0, 0);
		else
			texec(t->cap, t->SR, a, a, 0, 0, 0);
		goto done;
	}
	if ((t->dl || t->DL) && (t->al || t->AL)) {
		cpos(t, 0, bot - amnt);
		if ((amnt == 1 && t->dl) || !t->DL)
			while (a--)
				texec(t->cap, t->dl, 1, bot - amnt, 0, 0, 0);
		else
			texec(t->cap, t->DL, a, a, 0, 0, 0);
		a = amnt;
		cpos(t, 0, top);
		if ((amnt == 1 && t->al) || !t->AL)
			while (a--)
				texec(t->cap, t->al, 1, top, 0, 0, 0);
		else
			texec(t->cap, t->AL, a, a, 0, 0, 0);
		goto done;
	}
	msetI(t->updtab + top, 1, bot - top);
	return;
      done:
	mmove(t->scrn + (top + amnt) * t->co, t->scrn + top * t->co, (bot - top - amnt) * t->co * sizeof(int));

	if (!top && t->da) {
		msetI(t->scrn, -1, amnt * t->co);
		msetI(t->updtab, 1, amnt);
	} else
		msetI(t->scrn + t->co * top, ' ', amnt * t->co);
}

void nscroll(SCRN *t)
{
	int y, z, q, r, p;

	for (y = 0; y != t->li; ++y) {
		q = t->sary[y];
		if (have)
			return;
		if (q && q != t->li) {
			if (q > 0) {
				for (z = y; z != t->li && t->sary[z] == q; ++z)
					t->sary[z] = 0;
				doupscrl(t, y, z + q, q);
				y = z - 1;
			} else {
				for (r = y; r != t->li && (t->sary[r] < 0 || t->sary[r] == t->li); ++r) ;
				p = r - 1;
				do {
					q = t->sary[p];
					if (q && q != t->li) {
						for (z = p; t->sary[z] = 0, (z && t->sary[z - 1] == q); --z) ;
						dodnscrl(t, z + q, p + 1, -q);
						p = z + 1;
					}
				} while (p-- != y);
				y = r - 1;
			}
		}
	}
	msetI(t->sary, 0, t->li);
}

void npartial(SCRN *t)
{
	attr(t, 0);
	clrins(t);
	setregn(t, 0, t->li);
}

void nescape(SCRN *t)
{
	npartial(t);
	cpos(t, 0, t->li - 1);
	eraeol(t, 0, t->li - 1);
	if (t->te)
		texec(t->cap, t->te, 1, 0, 0, 0, 0);
}

void nreturn(SCRN *t)
{
	if (t->ti)
		texec(t->cap, t->ti, 1, 0, 0, 0, 0);
	if (!skiptop && t->cl)
		texec(t->cap, t->cl, 1, 0, 0, 0, 0);
	nredraw(t);
}

void nclose(SCRN *t)
{
	leave = 1;
	attr(t, 0);
	clrins(t);
	setregn(t, 0, t->li);
	cpos(t, 0, t->li - 1);
	if (t->te)
		texec(t->cap, t->te, 1, 0, 0, 0, 0);
	ttclose();
	rmcap(t->cap);
	joe_free(t->scrn);
	joe_free(t->sary);
	joe_free(t->ofst);
	joe_free(t->htab);
	joe_free(t->ary);
	joe_free(t);
}

void nscrldn(SCRN *t, int top, int bot, int amnt)
{
	int x;

	if (!amnt || top >= bot || bot > t->li)
		return;
	if ((amnt < bot - top && bot - top - amnt < amnt / 2) || !t->scroll)
		amnt = bot - top;
	if (amnt < bot - top) {
		for (x = bot; x != top + amnt; --x) {
			t->sary[x - 1] = (t->sary[x - amnt - 1] == t->li ? t->li : t->sary[x - amnt - 1] - amnt);
			t->updtab[x - 1] = t->updtab[x - amnt - 1];
		}
		for (x = top; x != top + amnt; ++x)
			t->updtab[x] = 1;
	}
	if (amnt > bot - top)
		amnt = bot - top;
	msetI(t->sary + top, t->li, amnt);
	if (amnt == bot - top)
		msetI(t->updtab + top, 1, amnt);
}

void nscrlup(SCRN *t, int top, int bot, int amnt)
{
	int x;

	if (!amnt || top >= bot || bot > t->li)
		return;
	if ((amnt < bot - top && bot - top - amnt < amnt / 2) || !t->scroll)
		amnt = bot - top;
	if (amnt < bot - top) {
		for (x = top + amnt; x != bot; ++x) {
			t->sary[x - amnt] = (t->sary[x] == t->li ? t->li : t->sary[x] + amnt);
			t->updtab[x - amnt] = t->updtab[x];
		}
		for (x = bot - amnt; x != bot; ++x)
			t->updtab[x] = 1;
	}
	if (amnt > bot - top)
		amnt = bot - top;
	msetI(t->sary + bot - amnt, t->li, amnt);
	if (amnt == bot - top)
		msetI(t->updtab + bot - amnt, 1, amnt);
}

extern volatile int dostaupd;

void nredraw(SCRN *t)
{
	dostaupd = 1;
	msetI(t->scrn, ' ', t->co * skiptop);
	msetI(t->scrn + skiptop * t->co, -1, (t->li - skiptop) * t->co);
	msetI(t->sary, 0, t->li);
	msetI(t->updtab + skiptop, -1, t->li - skiptop);
	t->x = -1;
	t->y = -1;
	t->top = t->li;
	t->bot = 0;
	t->attrib = -1;
	t->ins = -1;
	attr(t, 0);
	clrins(t);
	setregn(t, 0, t->li);

	if (!skiptop) {
		if (t->cl) {
			texec(t->cap, t->cl, 1, 0, 0, 0, 0);
			t->x = 0;
			t->y = 0;
			msetI(t->scrn, ' ', t->li * t->co);
		} else if (t->cd) {
			cpos(t, 0, 0);
			texec(t->cap, t->cd, 1, 0, 0, 0, 0);
			msetI(t->scrn, ' ', t->li * t->co);
		}
	}
}