/*      $NetBSD: ripoffline.c,v 1.7 2022/01/01 08:34:35 msaitoh Exp $   */

/*-
 * Copyright (c) 2017 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Roy Marples.
 *
 * 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.
 *
 * 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 FOUNDATION 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: ripoffline.c,v 1.7 2022/01/01 08:34:35 msaitoh Exp $");
#endif                          /* not lint */

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

/* List of ripoffline calls */
static struct ripoff {
        int     nlines;
        int     (*init)(WINDOW *, int);
} ripoffs[MAX_RIPS];
static int nrips;

/*
 * ripoffline --
 *      Ripoff a line from the top of bottom of stdscr.
 *      Must be called before initscr or newterm.
 */
int
ripoffline(int line, int (*init)(WINDOW *, int))
{

        __CTRACE(__CTRACE_WINDOW, "ripoffline: %d\n", line);

        if (nrips >= MAX_RIPS || init == NULL)
                return ERR; /* This makes sense, but not standards compliant. */
        if (line == 0)
                return OK;
        ripoffs[nrips].nlines = line < 0 ? -1 : 1;
        ripoffs[nrips++].init = init;
        return OK;
}

/*
 * __rippedlines --
 *      Returns the number of ripped lines from the screen.
 */
int
__rippedlines(const SCREEN *screen, int line)
{
        const struct __ripoff *rip;
        int i, n;

        n = 0;
        for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
                if (line < 1 && rip->nlines < 0)
                        n += -rip->nlines;
                else if (line > 0 && rip->nlines > 0)
                        n += rip->nlines;
        }
        return n;
}

/*
 * __ripoffscreen --
 *      Rips lines from the screen by creating a WINDOW per ripoffline call.
 *      Although the POSIX API only allows for one line WINDOWS to be created,
 *      this implementation allows for N lines if needed.
 */
int
__ripoffscreen(SCREEN *screen)
{
        int i, nlines, rbot, rtop;
        const struct ripoff *srip;
        struct __ripoff *rip;
        WINDOW *w;

        rip = screen->ripped;
        rbot = LINES;
        rtop = 0;
        for (i = 0, srip = ripoffs; i < nrips; i++, srip++) {
                if (srip->nlines == 0)
                        continue;
                nlines = srip->nlines < 0 ? -srip->nlines : srip->nlines;
                w = __newwin(screen, nlines, 0,
                    srip->nlines < 0 ? rbot - nlines : rtop,
                    0, FALSE, FALSE);
                if (w != NULL) {
                        rip->win = w;
                        rip->nlines = srip->nlines;
                        rip++;
                        screen->nripped++;
                        if (srip->nlines > 0)
                                rtop += nlines;
                        else
                                rbot -= nlines;
                }
                if (srip->init(w, COLS) == ERR)
                        return ERR;
#ifdef DEBUG
                if (w != NULL)
                        __CTRACE(__CTRACE_WINDOW,
                            "newterm: %p ripped %d line(s) from the %s\n",
                            w, nlines, srip->nlines < 0 ? "bottom" : "top");
#endif
        }
        nrips = 0; /* Reset the stack. */
        return OK;
}

/*
 * __ripoffresize --
 *      Called from resizeterm to ensure the ripped off lines are correctly
 *      placed and refreshed.
 */
int
__ripoffresize(SCREEN *screen)
{
        int rbot = screen->LINES, i, nlines, ret = OK;
        struct __ripoff *rip;

        for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
                if (rip->nlines == 0)
                        continue;
                nlines = rip->nlines < 0 ? -rip->nlines : rip->nlines;
                if (wresize(rip->win, nlines, screen->COLS) == ERR)
                        ret = ERR;
                if (rip->nlines < 0) {
                        /* Reposition the lower windows. */
                        if (mvwin(rip->win, rbot + rip->nlines, 0) == ERR)
                                ret = ERR;
                        else
                                rbot += rip->nlines;
                }
        }

        return ret;
}

/*
 *  __ripofftouch --
 *      Displays the ripped off lines from initscr.
 */
void
__ripofftouch(SCREEN *screen)
{
        int i;
        struct __ripoff *rip;

        for (i = 0, rip = screen->ripped; i < screen->nripped; i++, rip++) {
                touchwin(rip->win);
                wnoutrefresh(rip->win);
        }
}

/*
 * __unripoffline --
 *      Used by __slk_init to remove the ripoffline reservation it made
 *      because the terminal natively supports soft label keys.
 */
int
__unripoffline(int (*init)(WINDOW *, int))
{
        struct ripoff *rip;
        int i, unripped = 0;

        for (i = 0, rip = ripoffs; i < nrips; i++, rip++) {
                if (rip->init == init) {
                        rip->nlines = 0;
                        unripped++;
                }
        }
        return unripped;
}