/*      $NetBSD: fish.c,v 1.28 2024/11/18 20:53:45 hgutch Exp $ */

/*-
 * Copyright (c) 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Muffy Barkocy.
 *
 * 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) 1990, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)fish.c      8.1 (Berkeley) 5/31/93";
#else
__RCSID("$NetBSD: fish.c,v 1.28 2024/11/18 20:53:45 hgutch Exp $");
#endif
#endif /* not lint */

#include <sys/types.h>
#include <sys/wait.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <err.h>
#include "pathnames.h"

#define RANKS           13
#define HANDSIZE        7
#define CARDS           4
#define TOTCARDS        RANKS * CARDS

#define USER            1
#define COMPUTER        0
#define OTHER(a)        (1 - (a))

static const char *const cards[] = {
        "A", "2", "3", "4", "5", "6", "7",
        "8", "9", "10", "J", "Q", "K", NULL,
};
#define PRC(card)       (void)printf(" %s", cards[card])

static int promode;
static int asked[RANKS], comphand[RANKS], deck[TOTCARDS];
static int userasked[RANKS], userhand[RANKS];
static int curcard = TOTCARDS;

static void chkwinner(int, const int *);
static int compmove(void);
static int countbooks(const int *);
static int countcards(const int *);
static int drawcard(int, int *);
static int gofish(int, int, int *);
static void goodmove(int, int, int *, int *);
static void init(void);
static void instructions(void);
static void printhand(const int *);
static void printplayer(int);
static int promove(void);
static void usage(void) __dead;
static int usermove(void);

int
main(int argc, char **argv)
{
        int ch, move;

        /* Revoke setgid privileges */
        setgid(getgid());

        while ((ch = getopt(argc, argv, "p")) != -1)
                switch(ch) {
                case 'p':
                        promode = 1;
                        break;
                case '?':
                default:
                        usage();
                }

        instructions();
        init();

        if (arc4random_uniform(2) == 1) {
                printplayer(COMPUTER);
                (void)printf("get to start.\n");
                goto istart;
        }
        printplayer(USER);
        (void)printf("get to start.\n");

        for (;;) {
                move = usermove();
                if (!comphand[move]) {
                        if (gofish(move, USER, userhand))
                                continue;
                } else {
                        goodmove(USER, move, userhand, comphand);
                        continue;
                }

istart:         for (;;) {
                        move = compmove();
                        if (!userhand[move]) {
                                if (!gofish(move, COMPUTER, comphand))
                                        break;
                        } else
                                goodmove(COMPUTER, move, comphand, userhand);
                }
        }
        /* NOTREACHED */
}

static int
usermove(void)
{
        int n;
        const char *const *p;
        char buf[256];

        (void)printf("\nYour hand is:");
        printhand(userhand);

        for (;;) {
                (void)printf("You ask me for: ");
                (void)fflush(stdout);
                if (fgets(buf, sizeof(buf), stdin) == NULL)
                        exit(0);
                if (buf[0] == '\0')
                        continue;
                if (buf[0] == '\n') {
                        (void)printf("%d cards in my hand, %d in the pool.\n",
                            countcards(comphand), curcard);
                        (void)printf("My books:");
                        (void)countbooks(comphand);
                        continue;
                }
                buf[strlen(buf) - 1] = '\0';
                if (!strcasecmp(buf, "p")) {
                        if (!promode) {
                                promode = 1;
                                printf("Entering pro mode.\n");
                        }
                        else {
                                printf("Already in pro mode.\n");
                        }
                        continue;
                }
                if (!strcasecmp(buf, "quit"))
                        exit(0);
                for (p = cards; *p; ++p)
                        if (!strcasecmp(*p, buf))
                                break;
                if (!*p) {
                        (void)printf("I don't understand!\n");
                        continue;
                }
                n = p - cards;
                if (1 <= userhand[n] && userhand[n] <= 3) {
                        userasked[n] = 1;
                        return(n);
                }
                if (userhand[n] == 4) {
                        printf("You already have all of those.\n");
                        continue;
                }

                if (arc4random_uniform(3) == 1)
                        (void)printf("You don't have any of those!\n");
                else
                        (void)printf("You don't have any %s's!\n", cards[n]);
                if (arc4random_uniform(4) == 1)
                        (void)printf("No cheating!\n");
                (void)printf("Guess again.\n");
        }
        /* NOTREACHED */
}

static int
compmove(void)
{
        static int lmove;

        if (promode)
                lmove = promove();
        else {
                do {
                        lmove = (lmove + 1) % RANKS;
                } while (!comphand[lmove] || comphand[lmove] == CARDS);
        }
        asked[lmove] = 1;

        (void)printf("I ask you for: %s.\n", cards[lmove]);
        return(lmove);
}

static int
promove(void)
{
        int i, max;

        for (i = 0; i < RANKS; ++i)
                if (userasked[i] &&
                    comphand[i] > 0 && comphand[i] < CARDS) {
                        userasked[i] = 0;
                        return(i);
                }
        if (arc4random_uniform(3) == 1) {
                for (i = 0;; ++i)
                        if (comphand[i] && comphand[i] != CARDS) {
                                max = i;
                                break;
                        }
                while (++i < RANKS)
                        if (comphand[i] != CARDS &&
                            comphand[i] > comphand[max])
                                max = i;
                return(max);
        }
        if (arc4random_uniform(1024) == 0723) {
                for (i = 0; i < RANKS; ++i)
                        if (userhand[i] && comphand[i])
                                return(i);
        }
        for (;;) {
                for (i = 0; i < RANKS; ++i)
                        if (comphand[i] && comphand[i] != CARDS &&
                            !asked[i])
                                return(i);
                for (i = 0; i < RANKS; ++i)
                        asked[i] = 0;
        }
        /* NOTREACHED */
}

static int
drawcard(int player, int *hand)
{
        int card;

        ++hand[card = deck[--curcard]];
        if (player == USER || hand[card] == CARDS) {
                printplayer(player);
                (void)printf("drew %s", cards[card]);
                if (hand[card] == CARDS) {
                        (void)printf(" and made a book of %s's!\n",
                             cards[card]);
                        chkwinner(player, hand);
                } else
                        (void)printf(".\n");
        }
        return(card);
}

static int
gofish(int askedfor, int player, int *hand)
{
        printplayer(OTHER(player));
        (void)printf("say \"GO FISH!\"\n");
        if (askedfor == drawcard(player, hand)) {
                printplayer(player);
                (void)printf("drew the guess!\n");
                printplayer(player);
                (void)printf("get to ask again!\n");
                return(1);
        }
        return(0);
}

static void
goodmove(int player, int move, int *hand, int *opphand)
{
        printplayer(OTHER(player));
        (void)printf("have %d %s%s.\n",
            opphand[move], cards[move], opphand[move] == 1 ? "": "'s");

        hand[move] += opphand[move];
        opphand[move] = 0;

        if (hand[move] == CARDS) {
                printplayer(player);
                (void)printf("made a book of %s's!\n", cards[move]);
                chkwinner(player, hand);
        }

        chkwinner(OTHER(player), opphand);

        printplayer(player);
        (void)printf("get another guess!\n");
}

static void
chkwinner(int player, const int *hand)
{
        int cb, i, ub;

        for (i = 0; i < RANKS; ++i)
                if (hand[i] > 0 && hand[i] < CARDS)
                        return;
        printplayer(player);
        (void)printf("don't have any more cards!\n");
        (void)printf("My books:");
        cb = countbooks(comphand);
        (void)printf("Your books:");
        ub = countbooks(userhand);
        (void)printf("\nI have %d, you have %d.\n", cb, ub);
        if (ub > cb) {
                (void)printf("\nYou win!!!\n");
                if (arc4random_uniform(1024) == 0723)
                        (void)printf("Cheater, cheater, pumpkin eater!\n");
        } else if (cb > ub) {
                (void)printf("\nI win!!!\n");
                if (arc4random_uniform(1024) == 0723)
                        (void)printf("Hah!  Stupid peasant!\n");
        } else
                (void)printf("\nTie!\n");
        exit(0);
}

static void
printplayer(int player)
{
        switch (player) {
        case COMPUTER:
                (void)printf("I ");
                break;
        case USER:
                (void)printf("You ");
                break;
        }
}

static void
printhand(const int *hand)
{
        int book, i, j;

        for (book = i = 0; i < RANKS; i++)
                if (hand[i] < CARDS)
                        for (j = hand[i]; --j >= 0;)
                                PRC(i);
                else
                        ++book;
        if (book) {
                (void)printf(" + Book%s of", book > 1 ? "s" : "");
                for (i = 0; i < RANKS; i++)
                        if (hand[i] == CARDS)
                                PRC(i);
        }
        (void)putchar('\n');
}

static int
countcards(const int *hand)
{
        int i, count;

        for (count = i = 0; i < RANKS; i++)
                count += *hand++;
        return(count);
}

static int
countbooks(const int *hand)
{
        int i, count;

        for (count = i = 0; i < RANKS; i++)
                if (hand[i] == CARDS) {
                        ++count;
                        PRC(i);
                }
        if (!count)
                (void)printf(" none");
        (void)putchar('\n');
        return(count);
}

static void
init(void)
{
        int i, j, temp;

        for (i = 0; i < TOTCARDS; ++i)
                deck[i] = i % RANKS;
        for (i = 0; i < TOTCARDS - 1; ++i) {
                j = arc4random_uniform(TOTCARDS-i);
                if (j == 0)
                        continue;
                temp = deck[i];
                deck[i] = deck[i+j];
                deck[i+j] = temp;
        }
        for (i = 0; i < HANDSIZE; ++i) {
                ++userhand[deck[--curcard]];
                ++comphand[deck[--curcard]];
        }
}

static void
instructions(void)
{
        int input, c;
        pid_t pid;
        int fd;
        const char *pager;
        int status;

        (void)printf("Would you like instructions (y or n)? ");
        input = c = getchar();
        while (c != '\n') {
                c = getchar();
                if (c == EOF) {
                        exit(1);
                }
        }
        if (input != 'y')
                return;

        switch (pid = fork()) {
        case 0: /* child */
                if (!isatty(1))
                        pager = "cat";
                else {
                        if (!(pager = getenv("PAGER")) || (*pager == 0))
                                pager = _PATH_MORE;
                }
                if ((fd = open(_PATH_INSTR, O_RDONLY)) == -1)
                        err(1, "open %s", _PATH_INSTR);
                if (dup2(fd, 0) == -1)
                        err(1, "dup2");
                (void)execl("/bin/sh", "sh", "-c", pager, (char *) NULL);
                err(1, "exec sh -c %s", pager);
                /*NOTREACHED*/
        case -1:
                err(1, "fork");
                /*NOTREACHED*/
        default:
                (void)waitpid(pid, &status, 0);
                break;
        }
        (void)printf("Hit return to continue...\n");
        while ((input = getchar()) != EOF && input != '\n');
}

static void
usage(void)
{
        (void)fprintf(stderr, "usage: fish [-p]\n");
        exit(1);
}