/*      @(#)wwwrite.c   8.1 (Berkeley) 6/6/93   */
/*      $NetBSD: wwwrite.c,v 1.9 2009/04/14 08:50:06 lukem 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"
#include "tt.h"
#include "xx.h"
#include "char.h"

#define UPDATE() \
        if (!ISSET(w->ww_wflags, WWW_NOUPDATE) && w->ww_cur.r >= 0 && \
            w->ww_cur.r < wwnrow && wwtouched[w->ww_cur.r]) \
                wwupdate1(w->ww_cur.r, w->ww_cur.r + 1)

/*
 * To support control character expansion, we save the old
 * p and q values in r and s, and point p at the beginning
 * of the expanded string, and q at some safe place beyond it
 * (p + 10).  At strategic points in the loops, we check
 * for (r && !*p) and restore the saved values back into
 * p and q.  Essentially, we implement a stack of depth 2,
 * to avoid recursion, which might be a better idea.
 */
int
wwwrite(struct ww *w, const char *p, int n)
{
        int hascursor;
        const char *savep = p;
        const char *q = p + n;
        const char *r = NULL;
        const char *s = NULL;

        hascursor = ISSET(w->ww_wflags, WWW_HASCURSOR);
        if (hascursor)
                wwcursor(w, 0);
        while (p < q && !ISSET(w->ww_pflags, WWP_STOPPED) &&
            (!wwinterrupt() || ISSET(w->ww_wflags, WWW_NOINTR))) {
                if (r && !*p) {
                        p = r;
                        q = s;
                        r = NULL;
                        continue;
                }
                if (w->ww_wstate == 0 &&
                    (isprt(*p) ||
                    (ISSET(w->ww_wflags, WWW_UNCTRL) && isunctrl(*p)))) {
                        int i;
                        union ww_char *bp;
                        int col, col1;

                        if (ISSET(w->ww_wflags, WWW_INSERT)) {
                                /* this is very slow */
                                if (*p == '\t') {
                                        p++;
                                        w->ww_cur.c += 8 -
                                                ((w->ww_cur.c - w->ww_w.l) & 7);
                                        goto chklf;
                                }
                                if (!isprt(*p)) {
                                        r = p + 1;
                                        s = q;
                                        p = unctrl(*p);
                                        q = p + 10;
                                }
                                wwinschar(w, w->ww_cur.r, w->ww_cur.c,
                                        *p++, w->ww_modes);
                                goto right;
                        }

                        bp = &w->ww_buf[w->ww_cur.r][w->ww_cur.c];
                        i = w->ww_cur.c;
                        while (i < w->ww_w.r && p < q)
                                if (!*p && r) {
                                        p = r;
                                        q = s;
                                        r = NULL;
                                } else if (*p == '\t') {
                                        int tmp = 8 - ((i - w->ww_w.l) & 7);
                                        p++;
                                        i += tmp;
                                        bp += tmp;
                                } else if (isprt(*p)) {
                                        bp++->c_w = *p++
                                                | w->ww_modes << WWC_MSHIFT;
                                        i++;
                                } else if (ISSET(w->ww_wflags, WWW_UNCTRL) &&
                                           isunctrl(*p)) {
                                        r = p + 1;
                                        s = q;
                                        p = unctrl(*p);
                                        q = p + 10;
                                } else
                                        break;
                        col = MAX(w->ww_cur.c, w->ww_i.l);
                        col1 = MIN(i, w->ww_i.r);
                        w->ww_cur.c = i;
                        if (w->ww_cur.r >= w->ww_i.t
                            && w->ww_cur.r < w->ww_i.b) {
                                union ww_char *ns = wwns[w->ww_cur.r];
                                unsigned char *smap =
                                    &wwsmap[w->ww_cur.r][col];
                                char *win = w->ww_win[w->ww_cur.r];
                                int nchanged = 0;

                                bp = w->ww_buf[w->ww_cur.r];
                                for (i = col; i < col1; i++)
                                        if (*smap++ == w->ww_index) {
                                                nchanged++;
                                                ns[i].c_w = bp[i].c_w
                                                        ^ win[i] << WWC_MSHIFT;
                                        }
                                if (nchanged > 0)
                                        wwtouched[w->ww_cur.r] |= WWU_TOUCHED;
                        }
                chklf:
                        if (w->ww_cur.c >= w->ww_w.r)
                                goto crlf;
                } else switch (w->ww_wstate) {
                case 0:
                        switch (*p++) {
                        case '\n':
                                if (ISSET(w->ww_wflags, WWW_MAPNL))
                crlf:
                                        w->ww_cur.c = w->ww_w.l;
                lf:
                                UPDATE();
                                if (++w->ww_cur.r >= w->ww_w.b) {
                                        w->ww_cur.r = w->ww_w.b - 1;
                                        if (w->ww_w.b < w->ww_b.b) {
                                                (void) wwscroll1(w, w->ww_i.t,
                                                        w->ww_i.b, 1, 0);
                                                w->ww_buf++;
                                                w->ww_b.t--;
                                                w->ww_b.b--;
                                        } else
                                                wwdelline(w, w->ww_b.t);
                                }
                                break;
                        case '\b':
                                if (--w->ww_cur.c < w->ww_w.l) {
                                        w->ww_cur.c = w->ww_w.r - 1;
                                        goto up;
                                }
                                break;
                        case '\r':
                                w->ww_cur.c = w->ww_w.l;
                                break;
                        case ctrl('g'):
                                ttputc(ctrl('g'));
                                break;
                        case ctrl('['):
                                w->ww_wstate = 1;
                                break;
                        }
                        break;
                case 1:
                        w->ww_wstate = 0;
                        switch (*p++) {
                        case '@':
                                SET(w->ww_wflags, WWW_INSERT);
                                break;
                        case 'A':
                up:
                                UPDATE();
                                if (--w->ww_cur.r < w->ww_w.t) {
                                        w->ww_cur.r = w->ww_w.t;
                                        if (w->ww_w.t > w->ww_b.t) {
                                                (void) wwscroll1(w, w->ww_i.t,
                                                        w->ww_i.b, -1, 0);
                                                w->ww_buf--;
                                                w->ww_b.t++;
                                                w->ww_b.b++;
                                        } else
                                                wwinsline(w, w->ww_b.t);
                                }
                                break;
                        case 'B':
                                goto lf;
                        case 'C':
                right:
                                w->ww_cur.c++;
                                goto chklf;
                        case 'E':
                                w->ww_buf -= w->ww_w.t - w->ww_b.t;
                                w->ww_b.t = w->ww_w.t;
                                w->ww_b.b = w->ww_b.t + w->ww_b.nr;
                                w->ww_cur.r = w->ww_w.t;
                                w->ww_cur.c = w->ww_w.l;
                                wwclreos(w, w->ww_w.t, w->ww_w.l);
                                break;
                        case 'H':
                                UPDATE();
                                w->ww_cur.r = w->ww_w.t;
                                w->ww_cur.c = w->ww_w.l;
                                break;
                        case 'J':
                                wwclreos(w, w->ww_cur.r, w->ww_cur.c);
                                break;
                        case 'K':
                                wwclreol(w, w->ww_cur.r, w->ww_cur.c);
                                break;
                        case 'L':
                                UPDATE();
                                wwinsline(w, w->ww_cur.r);
                                break;
                        case 'M':
                                wwdelline(w, w->ww_cur.r);
                                break;
                        case 'N':
                                wwdelchar(w, w->ww_cur.r, w->ww_cur.c);
                                break;
                        case 'O':
                                CLR(w->ww_wflags, WWW_INSERT);
                                break;
                        case 'P':
                                wwinschar(w, w->ww_cur.r, w->ww_cur.c, ' ', 0);
                                break;
                        case 'X':
                                wwupdate();
                                break;
                        case 'Y':
                                UPDATE();
                                w->ww_wstate = 2;
                                break;
                        case 'Z':
                                wwupdate();
                                xxflush(0);
                                break;
                        case 's':
                                w->ww_wstate = 4;
                                break;
                        case 'r':
                                w->ww_wstate = 5;
                                break;
                        }
                        break;
                case 2:
                        w->ww_cur.r = w->ww_w.t +
                                (unsigned)(*p++ - ' ') % w->ww_w.nr;
                        w->ww_wstate = 3;
                        break;
                case 3:
                        w->ww_cur.c = w->ww_w.l +
                                (unsigned)(*p++ - ' ') % w->ww_w.nc;
                        w->ww_wstate = 0;
                        break;
                case 4:
                        w->ww_modes |= *p++ & wwavailmodes;
                        w->ww_wstate = 0;
                        break;
                case 5:
                        w->ww_modes &= ~*p++;
                        w->ww_wstate = 0;
                        break;
                }
        }
        if (hascursor)
                wwcursor(w, 1);
        wwnwwr++;
        wwnwwra += n;
        n = p - savep;
        wwnwwrc += n;
        return n;
}