/*-
 * (MPSAFE)
 *
 * Copyright (c) 1995-1998 Søren Schmidt
 * 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,
 *    without modification, immediately at the beginning of the file.
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 *
 * $FreeBSD: src/sys/modules/syscons/snake/snake_saver.c,v 1.26.2.2 2001/05/06 05:44:29 nyan Exp $
 * $DragonFly: src/sys/dev/misc/syscons/snake/snake_saver.c,v 1.8 2006/12/20 18:14:39 dillon Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/consio.h>
#include <sys/fbio.h>
#include <sys/thread.h>

#include <machine/pc/display.h>

#include <dev/video/fb/fbreg.h>
#include <dev/video/fb/splashreg.h>
#include "../syscons.h"

static u_char   *message;
static int      *messagep;
static int      messagelen;
static int      blanked;

static int
snake_saver(video_adapter_t *adp, int blank)
{
        static int      dirx, diry;
        int             f;
        sc_softc_t      *sc;
        scr_stat        *scp;

/* XXX hack for minimal changes. */
#define save    message
#define savs    messagep


        sc = sc_find_softc(adp, NULL);
        if (sc == NULL) {
                return EAGAIN;
        }
        scp = sc->cur_scp;

        if (blank) {
                if (adp->va_info.vi_flags & V_INFO_GRAPHICS) {
                        return EAGAIN;
                }
                if (blanked <= 0) {
                        sc_vtb_clear(&scp->scr, sc->scr_map[0x20],
                                     (FG_LIGHTGREY | BG_BLACK) << 8);
                        (*vidsw[adp->va_index]->set_hw_cursor)(adp, -1, -1);
                        sc_set_border(scp, 0);
                        dirx = (scp->xpos ? 1 : -1);
                        diry = (scp->ypos ?
                                scp->xsize : -scp->xsize);
                        for (f=0; f< messagelen; f++)
                                savs[f] = scp->xpos + scp->ypos*scp->xsize;
                        sc_vtb_putc(&scp->scr, savs[0], sc->scr_map[*save],
                                    (FG_LIGHTGREY | BG_BLACK) << 8);
                        blanked = 1;
                }
                if (blanked++ < 4) {
                        return 0;
                }
                blanked = 1;
                sc_vtb_putc(&scp->scr, savs[messagelen - 1], sc->scr_map[0x20],
                            (FG_LIGHTGREY | BG_BLACK) << 8);
                for (f=messagelen-1; f > 0; f--)
                        savs[f] = savs[f-1];
                f = savs[0];
                if ((f % scp->xsize) == 0 ||
                    (f % scp->xsize) == scp->xsize - 1 ||
                    (krandom() % 50) == 0)
                        dirx = -dirx;
                if ((f / scp->xsize) == 0 ||
                    (f / scp->xsize) == scp->ysize - 1 ||
                    (krandom() % 20) == 0)
                        diry = -diry;
                savs[0] += dirx + diry;
                for (f=messagelen-1; f>=0; f--)
                        sc_vtb_putc(&scp->scr, savs[f], sc->scr_map[save[f]],
                                    (FG_LIGHTGREY | BG_BLACK) << 8);
        } else {
                blanked = 0;
        }

        return 0;
}

static int
snake_init(video_adapter_t *adp)
{
        messagelen = strlen(ostype) + 1 + strlen(osrelease);
        message = kmalloc(messagelen + 1, M_SYSCONS, M_WAITOK);
        ksprintf(message, "%s %s", ostype, osrelease);
        messagep = kmalloc(messagelen * sizeof *messagep, M_SYSCONS, M_WAITOK);
        return 0;
}

static int
snake_term(video_adapter_t *adp)
{
        kfree(message, M_SYSCONS);
        kfree(messagep, M_SYSCONS);
        return 0;
}

static scrn_saver_t snake_module = {
        "snake_saver", snake_init, snake_term, snake_saver, NULL,
};

SAVER_MODULE(snake_saver, snake_module);