/*-
 * Copyright (c) 1998 Dag-Erling Coïdan Smørgrav
 * 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
 *    in this position and unchanged.
 * 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.
 *
 * $FreeBSD$
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/syslog.h>
#include <sys/consio.h>
#include <sys/fbio.h>

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

#define SAVER_NAME	 "rain_saver"
#define SCRW		 320
#define SCRH		 200
#define MAX		 63	/* number of colors (in addition to black) */
#define INCREMENT	 4	/* increment between colors */

#define RED(n)		 ((n) * 3 + 0)
#define GREEN(n)	 ((n) * 3 + 1)
#define BLUE(n)		 ((n) * 3 + 2)

static u_char		*vid;
static u_char		 rain_pal[768];
static int		 blanked;

static void
rain_update(video_adapter_t *adp)
{
	int i, t;

	t = rain_pal[BLUE(MAX)];
	for (i = MAX; i > 1; i--)
		rain_pal[BLUE(i)] = rain_pal[BLUE(i - 1)];
	rain_pal[BLUE(1)] = t;
	load_palette(adp, rain_pal);
}

static int
rain_saver(video_adapter_t *adp, int blank)
{
	int i, j, k, pl;
	
	if (blank) {
		/* switch to graphics mode */
		if (blanked <= 0) {
			pl = splhigh();
			set_video_mode(adp, M_VGA_CG320);
			load_palette(adp, rain_pal);
			set_border(adp, 0);
			blanked++;
			vid = (u_char *)adp->va_window;
			splx(pl);
			bzero(vid, SCRW * SCRH);
			for (i = 0; i < SCRW; i += 2)
				vid[i] = 1 + (random() % MAX);
			for (j = 1, k = SCRW; j < SCRH; j++)
				for (i = 0; i < SCRW; i += 2, k += 2)
					vid[k] = (vid[k - SCRW] < MAX) ?
					    1 + vid[k - SCRW] : 1;
		}
		
		/* update display */
		rain_update(adp);
	} else {
		blanked = 0;
	}
	return (0);
}

static int
rain_init(video_adapter_t *adp)
{
	video_info_t info;
	int i;
	
	/* check that the console is capable of running in 320x200x256 */
	if (get_mode_info(adp, M_VGA_CG320, &info)) {
		log(LOG_NOTICE,
		    "%s: the console does not support M_VGA_CG320\n",
		    SAVER_NAME);
		return (ENODEV);
	}
	
	/* intialize the palette */
	for (i = 1; i < MAX; i++)
		rain_pal[BLUE(i)] = rain_pal[BLUE(i - 1)] + INCREMENT;
	
	return (0);
}

static int
rain_term(video_adapter_t *adp)
{
	return (0);
}

static scrn_saver_t rain_module = {
	SAVER_NAME,
	rain_init,
	rain_term,
	rain_saver,
	NULL
};

SAVER_MODULE(rain_saver, rain_module);