/*      $NetBSD: rain.c,v 1.24 2024/02/28 23:24:52 charlotte Exp $      */

/*
 * Copyright (c) 1980, 1993
 *      The Regents of the University of California.  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.
 * 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 <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1980, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)rain.c      8.1 (Berkeley) 5/31/93";
#else
__RCSID("$NetBSD: rain.c,v 1.24 2024/02/28 23:24:52 charlotte Exp $");
#endif
#endif /* not lint */

/*
 * rain 11/3/1980 EPS/CITHEP
 * cc rain.c -o rain -O -ltermlib
 */

#include <sys/types.h>
#include <curses.h>
#include <err.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <limits.h>

static volatile sig_atomic_t sig_caught = 0;
static long cols;
static long lines;

int main(int, char **);
static void winupdate(void);
static void onsig(int);


int
main(int argc, char **argv)
{
        int x, y, j;
        unsigned int delay = 120000;
        unsigned long val = 0;
        int ch;
        char *ep;
        int xpos[5], ypos[5];

        while ((ch = getopt(argc, argv, "d:")) != -1)
                switch (ch) {
                case 'd':
                        val = strtoul(optarg, &ep, 0);
                        if (ep == optarg || *ep)
                                errx(1, "Invalid delay `%s'", optarg);
                        if (errno == ERANGE && val == ULONG_MAX)
                                err(1, "Invalid delay `%s'", optarg);
                        if (val >= 1000)
                                errx(1, "Invalid delay `%s' (1-999)", optarg);
                        delay = (unsigned int)val * 1000;  /* ms -> us */
                        break;
                default:
                        (void)fprintf(stderr, "Usage: %s [-d delay]\n",
                            getprogname());
                        return 1;
                }

        if (!initscr())
                errx(0, "couldn't initialize screen");
        winupdate();

        (void)signal(SIGHUP, onsig);
        (void)signal(SIGINT, onsig);
        (void)signal(SIGTERM, onsig);

        (void)curs_set(0);
        for (j = 4; j >= 0; --j) {
                xpos[j] = random() % cols + 2;
                ypos[j] = random() % lines + 2;
        }
        for (j = 0;;) {
                if (sig_caught) {
                        (void)endwin();
                        exit(0);
                }
                if (is_term_resized(LINES, COLS)) {
                        resizeterm(LINES, COLS);
                        winupdate();
                }
                x = random() % cols + 2;
                y = random() % lines + 2;
                (void)mvaddch(y, x, '.');
                (void)mvaddch(ypos[j], xpos[j], 'o');
                if (!j--)
                        j = 4;
                (void)mvaddch(ypos[j], xpos[j], 'O');
                if (!j--)
                        j = 4;
                (void)mvaddch(ypos[j] - 1, xpos[j], '-');
                (void)mvaddstr(ypos[j], xpos[j] - 1, "|.|");
                (void)mvaddch(ypos[j] + 1, xpos[j], '-');
                if (!j--)
                        j = 4;
                (void)mvaddch(ypos[j] - 2, xpos[j], '-');
                (void)mvaddstr(ypos[j] - 1, xpos[j] - 1, "/ \\");
                (void)mvaddstr(ypos[j], xpos[j] - 2, "| O |");
                (void)mvaddstr(ypos[j] + 1, xpos[j] - 1, "\\ /");
                (void)mvaddch(ypos[j] + 2, xpos[j], '-');
                if (!j--)
                        j = 4;
                (void)mvaddch(ypos[j] - 2, xpos[j], ' ');
                (void)mvaddstr(ypos[j] - 1, xpos[j] - 1, "   ");
                (void)mvaddstr(ypos[j], xpos[j] - 2, "     ");
                (void)mvaddstr(ypos[j] + 1, xpos[j] - 1, "   ");
                (void)mvaddch(ypos[j] + 2, xpos[j], ' ');
                xpos[j] = x;
                ypos[j] = y;
                (void)refresh();
                if (delay) (void)usleep(delay);
        }
}

static void
winupdate(void)
{
        cols = COLS - 4;
        lines = LINES - 4;
        if (cols == 0) cols++;
        if (lines == 0) lines++;
}

/* ARGSUSED */
static void
onsig(int dummy __unused)
{
        sig_caught = 1;
}