/*   $NetBSD: ins_wch.c,v 1.21 2024/12/23 02:58:03 blymn Exp $ */

/*
 * Copyright (c) 2005 The NetBSD Foundation Inc.
 * All rights reserved.
 *
 * This code is derived from code donated to the NetBSD Foundation
 * by Ruibiao Qiu <ruibiao@arl.wustl.edu,ruibiao@gmail.com>.
 *
 *
 * 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 NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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
__RCSID("$NetBSD: ins_wch.c,v 1.21 2024/12/23 02:58:03 blymn Exp $");
#endif                                            /* not lint */

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

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

/*
 * ins_wch --
 *      Do an insert-char on the line, leaving (cury, curx) unchanged.
 */
int
ins_wch(const cchar_t *wch)
{
        return wins_wch(stdscr, wch);
}

/*
 * mvins_wch --
 *        Do an insert-char on the line at (y, x).
 */
int
mvins_wch(int y, int x, const cchar_t *wch)
{
        return mvwins_wch(stdscr, y, x, wch);
}

/*
 * mvwins_wch --
 *        Do an insert-char on the line at (y, x) in the given window.
 */
int
mvwins_wch(WINDOW *win, int y, int x, const cchar_t *wch)
{
        if (wmove(win, y, x) == ERR)
                return ERR;

        return wins_wch(win, wch);
}

/*
 * wins_wch --
 *      Do an insert-char on the line, leaving (cury, curx) unchanged.
 */
int
wins_wch(WINDOW *win, const cchar_t *wch)
{
        __LDATA *start, *temp1, *temp2;
        __LINE *lnp;
        int cw, pcw, x, y, sx, ex, newx, i;
        nschar_t *np, *tnp;
        wchar_t ws[] = L"               ";

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

        /* check for non-spacing characters */
        if (!wch)
                return OK;
        cw = wcwidth(wch->vals[0]);
        __CTRACE(__CTRACE_INPUT, "wins_wch: wcwidth %d\n", cw);
        if (cw < 0)
                cw = 1;
        if (!cw)
                return wadd_wch( win, wch );

        x = win->curx;
        y = win->cury;
        __CTRACE(__CTRACE_INPUT, "wins_wch: (%d,%d)\n", y, x);
        switch (wch->vals[0]) {
                case L'\b':
                        if (--x < 0)
                                x = 0;
                        win->curx = x;
                        return OK;
                case L'\r':
                        win->curx = 0;
                        return OK;
                case L'\n':
                        wclrtoeol(win);
                        if (y == win->scr_b) {
                                if (!(win->flags & __SCROLLOK))
                                        return ERR;
                                scroll(win);
                        }
                        return OK;
                case L'\t':
                        if (wins_nwstr(win, ws, min(win->maxx - x,
                            TABSIZE - (x % TABSIZE))) == ERR)
                                return ERR;
                        return OK;
        }

        /* locate current cell */
        x = win->curx;
        y = win->cury;
        lnp = win->alines[y];
        start = &win->alines[y]->line[x];
        sx = x;
        pcw = start->wcols;
        if (pcw < 0) {
                start += pcw;
                sx += pcw;
        }
        if (cw > win->maxx - sx)
                return ERR;
        lnp->flags |= __ISDIRTY;
        newx = sx + win->ch_off;
        if (newx < *lnp->firstchp)
                *lnp->firstchp = newx;

        /* shift all complete characters */
        __CTRACE(__CTRACE_INPUT, "wins_wch: shift all characters\n");
        temp1 = &win->alines[y]->line[win->maxx - 1];
        temp2 = temp1 - cw;
        pcw = (temp2 + 1)->wcols;
        if (pcw < 0) {
                __CTRACE(__CTRACE_INPUT, "wins_wch: clear EOL\n");
                temp2 += pcw;
                while (temp1 > temp2 + cw) {
                        np = temp1->nsp;
                        if (np) {
                                while (np) {
                                        tnp = np->next;
                                        free(np);
                                        np = tnp;
                                }
                                temp1->nsp = NULL;
                        }
                        temp1->ch = win->bch;
                        if (_cursesi_copy_nsp(win->bnsp, temp1) == ERR)
                                return ERR;
                        temp1->attr = win->battr;
                        temp1->wcols = 1;
                        temp1--;
                }
        }
        while (temp2 >= start) {
                (void)memcpy(temp1, temp2, sizeof(__LDATA));
                temp1--, temp2--;
        }

        /* update character under cursor */
        start->nsp = NULL;
        start->ch = wch->vals[0];
        start->attr = wch->attributes & WA_ATTRIBUTES;
        start->wcols = cw;
        if (wch->elements > 1) {
                for (i = 1; i < wch->elements; i++) {
                        np = malloc(sizeof(nschar_t));
                        if (!np)
                                return ERR;
                        np->ch = wch->vals[i];
                        np->next = start->nsp;
                        start->nsp = np;
                }
        }
        __CTRACE(__CTRACE_INPUT, "wins_wch: insert (%x,%x,%p)\n",
            start->ch, start->attr, start->nsp);
        temp1 = start + 1;
        ex = x + 1;
        while (ex - x < cw) {
                temp1->ch = wch->vals[0];
                temp1->wcols = x - ex;
                temp1->nsp = NULL;
                temp1->cflags |= CA_CONTINUATION;
                ex++, temp1++;
        }

        newx = win->maxx - 1 + win->ch_off;
        if (newx > *lnp->lastchp)
                *lnp->lastchp = newx;
        __touchline(win, y, sx, (int)win->maxx - 1);
        __sync(win);
        return OK;
}