/*      $NetBSD: touchwin.c,v 1.35 2024/12/23 02:58:04 blymn Exp $      */

/*
* Copyright (c) 1981, 1993, 1994
*      The Regents of the University of California.  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. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*/

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)touchwin.c  8.2 (Berkeley) 5/4/94";
#else
__RCSID("$NetBSD: touchwin.c,v 1.35 2024/12/23 02:58:04 blymn Exp $");
#endif
#endif                          /* not lint */

#include "curses.h"
#include "curses_private.h"

static int _cursesi_touchline_force(WINDOW *, int, int, int, int);

/*
* __sync --
*      To be called after each window change.
*/
void
__sync(WINDOW *win)
{
       if (__predict_false(win == NULL))
               return;

       if (win->flags & __IMMEDOK)
               wrefresh(win);
       if (win->flags & __SYNCOK)
               wsyncup(win);
}

/*
* is_linetouched --
*      Indicate if line has been touched or not.
*/
bool
is_linetouched(WINDOW *win, int line)
{
       if (__predict_false(win == NULL))
               return ERR;

       if (line > win->maxy)
               return FALSE;

       __CTRACE(__CTRACE_LINE, "is_linetouched: (%p, line %d, dirty %d)\n",
           win, line, (win->alines[line]->flags & __ISDIRTY));
       return (win->alines[line]->flags & __ISDIRTY) != 0;
}

/*
* touchline --
*      Touch count lines starting at start.  This is the SUS v2 compliant
*      version.
*/
int
touchline(WINDOW *win, int start, int count)
{
       __CTRACE(__CTRACE_LINE, "touchline: (%p, %d, %d)\n", win, start, count);
       return wtouchln(win, start, count, 1);
}

/*
* wredrawln --
*      Mark count lines starting at start as corrupted.  Implemented using
*      wtouchln().
*/
int wredrawln(WINDOW *win, int start, int count)
{
       __CTRACE(__CTRACE_LINE, "wredrawln: (%p, %d, %d)\n", win, start, count);
       return wtouchln(win, start, count, 1);
}

/*
* is_wintouched --
*      Check if the window has been touched.
*/
bool
is_wintouched(WINDOW *win)
{
       int y, maxy;

       __CTRACE(__CTRACE_LINE, "is_wintouched: (%p, maxy %d)\n", win,
           win->maxy);
       if (__predict_false(win == NULL))
               return FALSE;

       maxy = win->maxy;
       for (y = 0; y < maxy; y++) {
               if (is_linetouched(win, y) == TRUE)
                       return TRUE;
       }

       return FALSE;
}

/*
* touchwin --
*      Make it look like the whole window has been changed.
*/
int
touchwin(WINDOW *win)
{
       __CTRACE(__CTRACE_LINE, "touchwin: (%p)\n", win);
       return wtouchln(win, 0, win->maxy, 1);
}

/*
* redrawwin --
*      Mark entire window as corrupted.  Implemented using wtouchln().
*/
int
redrawwin(WINDOW *win)
{
       __CTRACE(__CTRACE_LINE, "redrawwin: (%p)\n", win);
       return wtouchln(win, 0, win->maxy, 1);
}

/*
* untouchwin --
*       Make it look like the window has not been changed.
*/
int
untouchwin(WINDOW *win)
{
       __CTRACE(__CTRACE_LINE, "untouchwin: (%p)\n", win);
       return wtouchln(win, 0, win->maxy, 0);
}

/*
* wtouchln --
*      If changed is 1 then touch n lines starting at line.  If changed
*      is 0 then mark the lines as unchanged.
*/
int
wtouchln(WINDOW *win, int line, int n, int changed)
{
       int     y;
       __LINE  *wlp;

       __CTRACE(__CTRACE_LINE, "wtouchln: (%p) %d, %d, %d\n",
           win, line, n, changed);
       if (__predict_false(win == NULL))
               return FALSE;

       if (line < 0 || win->maxy <= line)
               return ERR;
       if (n < 0)
               return ERR;
       if (n > win->maxy - line)
               n = win->maxy - line;

       for (y = line; y < line + n; y++) {
               if (changed == 1)
                       _cursesi_touchline_force(win, y, 0,
                           (int) win->maxx - 1, 1);
               else {
                       wlp = win->alines[y];
                       if (*wlp->firstchp >= win->ch_off &&
                           *wlp->firstchp < win->maxx + win->ch_off)
                               *wlp->firstchp = win->maxx + win->ch_off;
                       if (*wlp->lastchp >= win->ch_off &&
                           *wlp->lastchp < win->maxx + win->ch_off)
                               *wlp->lastchp = win->ch_off;
                       wlp->flags &= ~(__ISDIRTY | __ISFORCED);
               }
       }

       return OK;
}

/*
* Touch all the lines in a window.  If force is set to 1 then screen
* update optimisation will disabled to force the change out.
*/
int
__touchwin(WINDOW *win, int force)
{
       int      y, maxy;

       __CTRACE(__CTRACE_LINE, "__touchwin: (%p)\n", win);
       maxy = win->maxy;
       for (y = 0; y < maxy; y++)
               _cursesi_touchline_force(win, y, 0, (int) win->maxx - 1,
                   force);
       return OK;
}

int
__touchline(WINDOW *win, int y, int sx, int ex)
{

       return _cursesi_touchline_force(win, y, sx, ex, 0);
}

/*
* Touch line y on window win starting from column sx and ending at
* column ex.  If force is 1 then we mark this line as a forced update
* which will bypass screen optimisation in the refresh code to rewrite
* this line unconditionally (even if refresh thinks the screen matches
* what is in the virtscr)
*/
static int
_cursesi_touchline_force(WINDOW *win, int y, int sx, int ex, int force)
{

       __CTRACE(__CTRACE_LINE, "__touchline: (%p, %d, %d, %d, %d)\n",
           win, y, sx, ex, force);
       __CTRACE(__CTRACE_LINE, "__touchline: first = %d, last = %d\n",
           *win->alines[y]->firstchp, *win->alines[y]->lastchp);
       sx += win->ch_off;
       ex += win->ch_off;
       win->alines[y]->flags |= __ISDIRTY;
       if (force == 1)
               win->alines[y]->flags |= __ISFORCED;
       /* firstchp/lastchp are shared between parent window and sub-window. */
       if (*win->alines[y]->firstchp > sx)
               *win->alines[y]->firstchp = sx;
       if (*win->alines[y]->lastchp < ex)
               *win->alines[y]->lastchp = ex;
       __CTRACE(__CTRACE_LINE, "__touchline: first = %d, last = %d\n",
           *win->alines[y]->firstchp, *win->alines[y]->lastchp);
       return OK;
}

void
wsyncup(WINDOW *win)
{

       if (__predict_false(win == NULL))
               return;

       do {
               __touchwin(win, 0);
               win = win->orig;
       } while (win);
}

void
wsyncdown(WINDOW *win)
{
       if (__predict_false(win == NULL))
               return;

       WINDOW *w = win->orig;

       while (w) {
               if (is_wintouched(w)) {
                       __touchwin(win, 0);
                       break;
               }
               w = w->orig;
       }
}