/*      @(#)wwdelete.c  8.1 (Berkeley) 6/6/93   */
/*      $NetBSD: wwdelete.c,v 1.7 2003/08/07 11:17:38 agc Exp $ */

/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Wang at The University of California, Berkeley.
 *
 * 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 "ww.h"

/*
 * Pull w free from the cover list.
 */
void
wwdelete(struct ww *w)
{
        int i;

        for (i = w->ww_i.t; i < w->ww_i.b; i++) {
                int j;
                unsigned char *smap = wwsmap[i];
                union ww_char *ns = wwns[i];
                int nchanged = 0;

                for (j = w->ww_i.l; j < w->ww_i.r; j++)
                        if (smap[j] == w->ww_index) {
                                smap[j] = WWX_NOBODY;
                                ns[j].c_w = ' ';
                                nchanged++;
                        }
                if (nchanged > 0)
                        wwtouched[i] |= WWU_TOUCHED;
        }

        {
                struct ww *wp;

                for (wp = w->ww_forw; wp != &wwhead; wp = wp->ww_forw)
                        wp->ww_order--;
        }

        if (w->ww_forw != &wwhead)
                wwdelete1(w->ww_forw,
                        w->ww_i.t, w->ww_i.b, w->ww_i.l, w->ww_i.r);

        w->ww_back->ww_forw = w->ww_forw;
        w->ww_forw->ww_back = w->ww_back;
        w->ww_forw = w->ww_back = 0;
}

void
wwdelete1(struct ww *w, int t, int b, int l, int r)
{
        int i;
        int tt, bb, ll, rr;
        char hasglass;

again:
        hasglass = 0;
        tt = MAX(t, w->ww_i.t);
        bb = MIN(b, w->ww_i.b);
        ll = MAX(l, w->ww_i.l);
        rr = MIN(r, w->ww_i.r);
        if (tt >= bb || ll >= rr) {
                if ((w = w->ww_forw) == &wwhead)
                        return;
                goto again;
        }
        for (i = tt; i < bb; i++) {
                int j;
                unsigned char *smap = wwsmap[i];
                union ww_char *ns = wwns[i];
                char *win = w->ww_win[i];
                union ww_char *buf = w->ww_buf[i];
                int nvis = w->ww_nvis[i];
                int nchanged = 0;

                for (j = ll; j < rr; j++) {
                        if (smap[j] != WWX_NOBODY)
                                continue;
                        if (win[j] & WWM_GLS) {
                                hasglass = 1;
                                continue;
                        }
                        smap[j] = w->ww_index;
                        ns[j].c_w = buf[j].c_w ^ win[j] << WWC_MSHIFT;
                        nchanged++;
                        if (win[j] == 0)
                                nvis++;
                }
                if (nchanged > 0)
                        wwtouched[i] |= WWU_TOUCHED;
                w->ww_nvis[i] = nvis;
        }
        if ((w = w->ww_forw) == &wwhead)
                return;
        if (hasglass)
                goto again;
        if (tt > t)
                wwdelete1(w, t, tt, l, r);
        if (bb < b)
                wwdelete1(w, bb, b, l, r);
        if (ll > l)
                wwdelete1(w, tt, bb, l, ll);
        if (rr < r)
                wwdelete1(w, tt, bb, rr, r);
}