/*      $NetBSD: delch.c,v 1.31 2024/12/23 02:58:03 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[] = "@(#)delch.c     8.2 (Berkeley) 5/4/94";
#else
__RCSID("$NetBSD: delch.c,v 1.31 2024/12/23 02:58:03 blymn Exp $");
#endif
#endif                          /* not lint */

#include <string.h>
#include <stdlib.h>

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

#ifndef _CURSES_USE_MACROS
/*
* delch --
*      Do a delete-char on the line, leaving (cury, curx) unchanged.
*/
int
delch(void)
{
       return wdelch(stdscr);
}

/*
* mvdelch --
*      Do a delete-char on the line at (y, x) on stdscr.
*/
int
mvdelch(int y, int x)
{
       return mvwdelch(stdscr, y, x);
}

/*
* mvwdelch --
*      Do a delete-char on the line at (y, x) of the given window.
*/
int
mvwdelch(WINDOW *win, int y, int x)
{
       if (wmove(win, y, x) == ERR)
               return ERR;

       return wdelch(win);
}

#endif

/*
* wdelch --
*      Do a delete-char on the line, leaving (cury, curx) unchanged.
*/
int
wdelch(WINDOW *win)
{
       __LDATA *end, *temp1, *temp2;

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

#ifndef HAVE_WCHAR
       end = &win->alines[win->cury]->line[win->maxx - 1];
       temp1 = &win->alines[win->cury]->line[win->curx];
       temp2 = temp1 + 1;
       while (temp1 < end) {
               (void)memcpy(temp1, temp2, sizeof(__LDATA));
               temp1++, temp2++;
       }
       temp1->ch = win->bch;
       temp1->cflags = CA_BACKGROUND;
       if (__using_color && win != curscr)
               temp1->attr = win->battr & __COLOR;
       else
               temp1->attr = 0;
       __touchline(win, (int)win->cury, (int)win->curx, (int)win->maxx - 1);
       return OK;
#else
       int cw, sx;
       nschar_t *np, *tnp;

       end = &win->alines[win->cury]->line[win->maxx - 1];
       sx = win->curx;
       temp1 = &win->alines[win->cury]->line[win->curx];
       cw = temp1->wcols;
       if (cw < 0) {
               temp1 += cw;
               sx += cw;
               cw = temp1->wcols;
       }
       np = temp1->nsp;
       if (np) {
               while (np) {
                       tnp = np->next;
                       free(np);
                       np = tnp;
               }
               temp1->nsp = NULL;
       }
       if (sx + cw < win->maxx) {
               temp2 = temp1 + cw;
               while (temp1 < end - (cw - 1)) {
                       (void)memcpy(temp1, temp2, sizeof(__LDATA));
                       temp1++, temp2++;
               }
       }
       while (temp1 <= end) {
               temp1->ch = win->bch;
               temp1->cflags |= CA_BACKGROUND;
               temp1->cflags &= ~CA_CONTINUATION;
               temp1->attr = win->battr;
               if (_cursesi_copy_nsp(win->bnsp, temp1) == ERR)
                       return ERR;
               temp1->wcols = 1;
               temp1++;
       }
       __touchline(win, (int)win->cury, sx, (int)win->maxx - 1);
       __sync(win);
       return OK;
#endif /* HAVE_WCHAR */
}