bs.c   [plain text]

/* 
 * bs.c - original author: Bruce Holloway
 *		salvo option by: Chuck A DeGaul
 * with improved user interface, autoconfiguration and code cleanup
 *		by Eric S. Raymond <esr@snark.thyrsus.com>
 * v1.2 with color support and minor portability fixes, November 1990
 * v2.0 featuring strict ANSI/POSIX conformance, November 1993.
 * v2.1 with ncurses mouse support, September 1995
 *
 * $Id: bs.c,v 1.39 2003/12/06 18:10:13 tom Exp $
 */

#include <time.h>

#include <test.priv.h>

#ifndef SIGIOT
#define SIGIOT SIGABRT
#endif

static int getcoord(int);

/*
 * Constants for tuning the random-fire algorithm. It prefers moves that
 * diagonal-stripe the board with a stripe separation of srchstep. If
 * no such preferred moves are found, srchstep is decremented.
 */
#define BEGINSTEP	3	/* initial value of srchstep */

/* miscellaneous constants */
#define SHIPTYPES	5
#define	OTHER		(1-turn)
#define PLAYER		0
#define COMPUTER	1
#define MARK_HIT	'H'
#define MARK_MISS	'o'
#define CTRLC		'\003'	/* used as terminate command */
#define FF		'\014'	/* used as redraw command */

/* coordinate handling */
#define BWIDTH		10
#define BDEPTH		10

/* display symbols */
#define SHOWHIT		'*'
#define SHOWSPLASH	' '
#define IS_SHIP(c)	(isupper(UChar(c)) ? TRUE : FALSE)

/* how to position us on player board */
#define PYBASE	3
#define PXBASE	3
#define PY(y)	(PYBASE + (y))
#define PX(x)	(PXBASE + (x)*3)
#define pgoto(y, x)	(void)move(PY(y), PX(x))

/* how to position us on cpu board */
#define CYBASE	3
#define CXBASE	48
#define CY(y)	(CYBASE + (y))
#define CX(x)	(CXBASE + (x)*3)
#define CYINV(y)	((y) - CYBASE)
#define CXINV(x)	(((x) - CXBASE) / 3)
#define cgoto(y, x)	(void)move(CY(y), CX(x))

#define ONBOARD(x, y)	(x >= 0 && x < BWIDTH && y >= 0 && y < BDEPTH)

/* other board locations */
#define COLWIDTH	80
#define PROMPTLINE	21	/* prompt line */
#define SYBASE		CYBASE + BDEPTH + 3	/* move key diagram */
#define SXBASE		63
#define MYBASE		SYBASE - 1	/* diagram caption */
#define MXBASE		64
#define HYBASE		SYBASE - 1	/* help area */
#define HXBASE		0

/* this will need to be changed if BWIDTH changes */
static char numbers[] = "   0  1  2  3  4  5  6  7  8  9";

static char carrier[] = "Aircraft Carrier";
static char battle[] = "Battleship";
static char sub[] = "Submarine";
static char destroy[] = "Destroyer";
static char ptboat[] = "PT Boat";

static char name[40];
static char dftname[] = "stranger";

/* direction constants */
#define E	0
#define SE	1
#define S	2
#define SW	3
#define W	4
#define NW	5
#define N	6
#define NE	7
static int xincr[8] =
{1, 1, 0, -1, -1, -1, 0, 1};
static int yincr[8] =
{0, 1, 1, 1, 0, -1, -1, -1};

/* current ship position and direction */
static int curx = (BWIDTH / 2);
static int cury = (BDEPTH / 2);

typedef struct {
    char *name;			/* name of the ship type */
    int hits;			/* how many times has this ship been hit? */
    char symbol;		/* symbol for game purposes */
    int length;			/* length of ship */
    int x, y;			/* coordinates of ship start point */
    int dir;			/* direction of `bow' */
    bool placed;		/* has it been placed on the board? */
} ship_t;

static bool checkplace(int b, ship_t * ss, int vis);

#define SHIPIT(name, symbol, length) { name, 0, symbol, length, 0,0, 0, FALSE }

static ship_t plyship[SHIPTYPES] =
{
    SHIPIT(carrier, 'A', 5),
    SHIPIT(battle, 'B', 4),
    SHIPIT(destroy, 'D', 3),
    SHIPIT(sub, 'S', 3),
    SHIPIT(ptboat, 'P', 2),
};

static ship_t cpuship[SHIPTYPES] =
{
    SHIPIT(carrier, 'A', 5),
    SHIPIT(battle, 'B', 4),
    SHIPIT(destroy, 'D', 3),
    SHIPIT(sub, 'S', 3),
    SHIPIT(ptboat, 'P', 2),
};

/* "Hits" board, and main board. */
static char hits[2][BWIDTH][BDEPTH];
static char board[2][BWIDTH][BDEPTH];

static int turn;		/* 0=player, 1=computer */
static int plywon = 0, cpuwon = 0;	/* How many games has each won? */

static int salvo, blitz, closepack;

#define	PR	(void)addstr

static RETSIGTYPE uninitgame(int sig) GCC_NORETURN;

static RETSIGTYPE uninitgame(int sig GCC_UNUSED)
/* end the game, either normally or due to signal */
{
    clear();
    (void) refresh();
    (void) reset_shell_mode();
    (void) echo();
    (void) endwin();
    ExitProgram(sig ? EXIT_FAILURE : EXIT_SUCCESS);
}

static void
announceopts(void)
/* announce which game options are enabled */
{
    if (salvo || blitz || closepack) {
	(void) printw("Playing optional game (");
	if (salvo)
	    (void) printw("salvo, ");
	else
	    (void) printw("nosalvo, ");
	if (blitz)
	    (void) printw("blitz ");
	else
	    (void) printw("noblitz, ");
	if (closepack)
	    (void) printw("closepack)");
	else
	    (void) printw("noclosepack)");
    } else
	(void) printw(
			 "Playing standard game (noblitz, nosalvo, noclosepack)");
}

static void
intro(void)
{
    char *tmpname;

    srand((unsigned) (time(0L) + getpid()));	/* Kick the random number generator */

    (void) signal(SIGINT, uninitgame);
    (void) signal(SIGINT, uninitgame);
    (void) signal(SIGIOT, uninitgame);	/* for assert(3) */
    if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
	(void) signal(SIGQUIT, uninitgame);

    if ((tmpname = getlogin()) != 0) {
	(void) strcpy(name, tmpname);
	name[0] = toupper(name[0]);
    } else
	(void) strcpy(name, dftname);

    (void) initscr();
    keypad(stdscr, TRUE);
    (void) def_prog_mode();
    (void) nonl();
    (void) cbreak();
    (void) noecho();

#ifdef PENGUIN
    (void) clear();
    (void) mvaddstr(4, 29, "Welcome to Battleship!");
    (void) move(8, 0);
    PR("                                                  \\\n");
    PR("                           \\                     \\ \\\n");
    PR("                          \\ \\                   \\ \\ \\_____________\n");
    PR("                         \\ \\ \\_____________      \\ \\/            |\n");
    PR("                          \\ \\/             \\      \\/             |\n");
    PR("                           \\/               \\_____/              |__\n");
    PR("           ________________/                                       |\n");
    PR("           \\  S.S. Penguin                                         |\n");
    PR("            \\                                                     /\n");
    PR("             \\___________________________________________________/\n");

    (void) mvaddstr(22, 27, "Hit any key to continue...");
    (void) refresh();
    (void) getch();
#endif /* PENGUIN */

#ifdef A_COLOR
    start_color();

    init_pair(COLOR_BLACK, COLOR_BLACK, COLOR_BLACK);
    init_pair(COLOR_GREEN, COLOR_GREEN, COLOR_BLACK);
    init_pair(COLOR_RED, COLOR_RED, COLOR_BLACK);
    init_pair(COLOR_CYAN, COLOR_CYAN, COLOR_BLACK);
    init_pair(COLOR_WHITE, COLOR_WHITE, COLOR_BLACK);
    init_pair(COLOR_MAGENTA, COLOR_MAGENTA, COLOR_BLACK);
    init_pair(COLOR_BLUE, COLOR_BLUE, COLOR_BLACK);
    init_pair(COLOR_YELLOW, COLOR_YELLOW, COLOR_BLACK);
#endif /* A_COLOR */

#ifdef NCURSES_MOUSE_VERSION
    (void) mousemask(BUTTON1_CLICKED, (mmask_t *) NULL);
#endif /* NCURSES_MOUSE_VERSION */
}

/* VARARGS1 */
static void
prompt(int n, const char *f, const char *s)
/* print a message at the prompt line */
{
    (void) move(PROMPTLINE + n, 0);
    (void) clrtoeol();
    (void) printw(f, s);
    (void) refresh();
}

static void
error(NCURSES_CONST char *s)
{
    (void) move(PROMPTLINE + 2, 0);
    (void) clrtoeol();
    if (s) {
	(void) addstr(s);
	(void) beep();
    }
}

static void
placeship(int b, ship_t * ss, int vis)
{
    int l;

    for (l = 0; l < ss->length; ++l) {
	int newx = ss->x + l * xincr[ss->dir];
	int newy = ss->y + l * yincr[ss->dir];

	board[b][newx][newy] = ss->symbol;
	if (vis) {
	    pgoto(newy, newx);
	    (void) addch((chtype) ss->symbol);
	}
    }
    ss->hits = 0;
}

static int
rnd(int n)
{
    return (((rand() & 0x7FFF) % n));
}

static void
randomplace(int b, ship_t * ss)
/* generate a valid random ship placement into px,py */
{

    do {
	ss->dir = rnd(2) ? E : S;
	ss->x = rnd(BWIDTH - (ss->dir == E ? ss->length : 0));
	ss->y = rnd(BDEPTH - (ss->dir == S ? ss->length : 0));
    } while
	(!checkplace(b, ss, FALSE));
}

static void
initgame(void)
{
    int i, j, unplaced;
    ship_t *ss;

    (void) clear();
    (void) mvaddstr(0, 35, "BATTLESHIPS");
    (void) move(PROMPTLINE + 2, 0);
    announceopts();

    memset(board, 0, sizeof(char) * BWIDTH * BDEPTH * 2);
    memset(hits, 0, sizeof(char) * BWIDTH * BDEPTH * 2);
    for (i = 0; i < SHIPTYPES; i++) {
	ss = cpuship + i;

	ss->x =
	    ss->y =
	    ss->dir =
	    ss->hits = 0;
	ss->placed = FALSE;

	ss = plyship + i;

	ss->x =
	    ss->y =
	    ss->dir =
	    ss->hits = 0;
	ss->placed = FALSE;
    }

    /* draw empty boards */
    (void) mvaddstr(PYBASE - 2, PXBASE + 5, "Main Board");
    (void) mvaddstr(PYBASE - 1, PXBASE - 3, numbers);
    for (i = 0; i < BDEPTH; ++i) {
	(void) mvaddch(PYBASE + i, PXBASE - 3, (chtype) (i + 'A'));
#ifdef A_COLOR
	if (has_colors())
	    attron(COLOR_PAIR(COLOR_BLUE));
#endif /* A_COLOR */
	(void) addch(' ');
	for (j = 0; j < BWIDTH; j++)
	    (void) addstr(" . ");
#ifdef A_COLOR
	attrset(0);
#endif /* A_COLOR */
	(void) addch(' ');
	(void) addch((chtype) (i + 'A'));
    }
    (void) mvaddstr(PYBASE + BDEPTH, PXBASE - 3, numbers);
    (void) mvaddstr(CYBASE - 2, CXBASE + 7, "Hit/Miss Board");
    (void) mvaddstr(CYBASE - 1, CXBASE - 3, numbers);
    for (i = 0; i < BDEPTH; ++i) {
	(void) mvaddch(CYBASE + i, CXBASE - 3, (chtype) (i + 'A'));
#ifdef A_COLOR
	if (has_colors())
	    attron(COLOR_PAIR(COLOR_BLUE));
#endif /* A_COLOR */
	(void) addch(' ');
	for (j = 0; j < BWIDTH; j++)
	    (void) addstr(" . ");
#ifdef A_COLOR
	attrset(0);
#endif /* A_COLOR */
	(void) addch(' ');
	(void) addch((chtype) (i + 'A'));
    }

    (void) mvaddstr(CYBASE + BDEPTH, CXBASE - 3, numbers);

    (void) mvprintw(HYBASE, HXBASE,
		    "To position your ships: move the cursor to a spot, then");
    (void) mvprintw(HYBASE + 1, HXBASE,
		    "type the first letter of a ship type to select it, then");
    (void) mvprintw(HYBASE + 2, HXBASE,
		    "type a direction ([hjkl] or [4862]), indicating how the");
    (void) mvprintw(HYBASE + 3, HXBASE,
		    "ship should be pointed. You may also type a ship letter");
    (void) mvprintw(HYBASE + 4, HXBASE,
		    "followed by `r' to position it randomly, or type `R' to");
    (void) mvprintw(HYBASE + 5, HXBASE,
		    "place all remaining ships randomly.");

    (void) mvaddstr(MYBASE, MXBASE, "Aiming keys:");
    (void) mvaddstr(SYBASE, SXBASE, "y k u    7 8 9");
    (void) mvaddstr(SYBASE + 1, SXBASE, " \\|/      \\|/ ");
    (void) mvaddstr(SYBASE + 2, SXBASE, "h-+-l    4-+-6");
    (void) mvaddstr(SYBASE + 3, SXBASE, " /|\\      /|\\ ");
    (void) mvaddstr(SYBASE + 4, SXBASE, "b j n    1 2 3");

    /* have the computer place ships */
    for (ss = cpuship; ss < cpuship + SHIPTYPES; ss++) {
	randomplace(COMPUTER, ss);
	placeship(COMPUTER, ss, FALSE);
    }

    ss = (ship_t *) NULL;
    do {
	char c, docked[SHIPTYPES + 2], *cp = docked;

	/* figure which ships still wait to be placed */
	*cp++ = 'R';
	for (i = 0; i < SHIPTYPES; i++)
	    if (!plyship[i].placed)
		*cp++ = plyship[i].symbol;
	*cp = '\0';

	/* get a command letter */
	prompt(1, "Type one of [%s] to pick a ship.", docked + 1);
	do {
	    c = getcoord(PLAYER);
	} while
	    (!strchr(docked, c));

	if (c == 'R')
	    (void) ungetch('R');
	else {
	    /* map that into the corresponding symbol */
	    for (ss = plyship; ss < plyship + SHIPTYPES; ss++)
		if (ss->symbol == c)
		    break;

	    prompt(1, "Type one of [hjklrR] to place your %s.", ss->name);
	    pgoto(cury, curx);
	}

	do {
	    c = getch();
	} while
	    (!strchr("hjklrR", c) || c == FF);

	if (c == FF) {
	    (void) clearok(stdscr, TRUE);
	    (void) refresh();
	} else if (c == 'r') {
	    prompt(1, "Random-placing your %s", ss->name);
	    randomplace(PLAYER, ss);
	    placeship(PLAYER, ss, TRUE);
	    error((char *) NULL);
	    ss->placed = TRUE;
	} else if (c == 'R') {
	    prompt(1, "Placing the rest of your fleet at random...", "");
	    for (ss = plyship; ss < plyship + SHIPTYPES; ss++)
		if (!ss->placed) {
		    randomplace(PLAYER, ss);
		    placeship(PLAYER, ss, TRUE);
		    ss->placed = TRUE;
		}
	    error((char *) NULL);
	} else if (strchr("hjkl8462", c)) {
	    ss->x = curx;
	    ss->y = cury;

	    switch (c) {
	    case 'k':
	    case '8':
		ss->dir = N;
		break;
	    case 'j':
	    case '2':
		ss->dir = S;
		break;
	    case 'h':
	    case '4':
		ss->dir = W;
		break;
	    case 'l':
	    case '6':
		ss->dir = E;
		break;
	    }

	    if (checkplace(PLAYER, ss, TRUE)) {
		placeship(PLAYER, ss, TRUE);
		error((char *) NULL);
		ss->placed = TRUE;
	    }
	}

	for (unplaced = i = 0; i < SHIPTYPES; i++)
	    unplaced += !plyship[i].placed;
    } while
	(unplaced);

    turn = rnd(2);

    (void) mvprintw(HYBASE, HXBASE,
		    "To fire, move the cursor to your chosen aiming point   ");
    (void) mvprintw(HYBASE + 1, HXBASE,
		    "and strike any key other than a motion key.            ");
    (void) mvprintw(HYBASE + 2, HXBASE,
		    "                                                       ");
    (void) mvprintw(HYBASE + 3, HXBASE,
		    "                                                       ");
    (void) mvprintw(HYBASE + 4, HXBASE,
		    "                                                       ");
    (void) mvprintw(HYBASE + 5, HXBASE,
		    "                                                       ");

    (void) prompt(0, "Press any key to start...", "");
    (void) getch();
}

static int
getcoord(int atcpu)
{
    int ny, nx, c;

    if (atcpu)
	cgoto(cury, curx);
    else
	pgoto(cury, curx);
    (void) refresh();
    for (;;) {
	if (atcpu) {
	    (void) mvprintw(CYBASE + BDEPTH + 1, CXBASE + 11, "(%d, %c)",
			    curx, 'A' + cury);
	    cgoto(cury, curx);
	} else {
	    (void) mvprintw(PYBASE + BDEPTH + 1, PXBASE + 11, "(%d, %c)",
			    curx, 'A' + cury);
	    pgoto(cury, curx);
	}

	switch (c = getch()) {
	case 'k':
	case '8':
	case KEY_UP:
	    ny = cury + BDEPTH - 1;
	    nx = curx;
	    break;
	case 'j':
	case '2':
	case KEY_DOWN:
	    ny = cury + 1;
	    nx = curx;
	    break;
	case 'h':
	case '4':
	case KEY_LEFT:
	    ny = cury;
	    nx = curx + BWIDTH - 1;
	    break;
	case 'l':
	case '6':
	case KEY_RIGHT:
	    ny = cury;
	    nx = curx + 1;
	    break;
	case 'y':
	case '7':
	case KEY_A1:
	    ny = cury + BDEPTH - 1;
	    nx = curx + BWIDTH - 1;
	    break;
	case 'b':
	case '1':
	case KEY_C1:
	    ny = cury + 1;
	    nx = curx + BWIDTH - 1;
	    break;
	case 'u':
	case '9':
	case KEY_A3:
	    ny = cury + BDEPTH - 1;
	    nx = curx + 1;
	    break;
	case 'n':
	case '3':
	case KEY_C3:
	    ny = cury + 1;
	    nx = curx + 1;
	    break;
	case FF:
	    nx = curx;
	    ny = cury;
	    (void) clearok(stdscr, TRUE);
	    (void) refresh();
	    break;
#ifdef NCURSES_MOUSE_VERSION
	case KEY_MOUSE:
	    {
		MEVENT myevent;

		getmouse(&myevent);
		if (atcpu
		    && myevent.y >= CY(0) && myevent.y <= CY(BDEPTH)
		    && myevent.x >= CX(0) && myevent.x <= CX(BDEPTH)) {
		    curx = CXINV(myevent.x);
		    cury = CYINV(myevent.y);
		    return (' ');
		} else {
		    beep();
		    continue;
		}
	    }
	    /* no fall through */
#endif /* NCURSES_MOUSE_VERSION */

	default:
	    if (atcpu)
		(void) mvaddstr(CYBASE + BDEPTH + 1, CXBASE + 11, "      ");
	    else
		(void) mvaddstr(PYBASE + BDEPTH + 1, PXBASE + 11, "      ");
	    return (c);
	}

	curx = nx % BWIDTH;
	cury = ny % BDEPTH;
    }
}

static bool
collidecheck(int b, int y, int x)
/* is this location on the selected zboard adjacent to a ship? */
{
    bool collide;

    /* anything on the square */
    if ((collide = IS_SHIP(board[b][x][y])) != FALSE)
	return (collide);

    /* anything on the neighbors */
    if (!closepack) {
	int i;

	for (i = 0; i < 8; i++) {
	    int xend, yend;

	    yend = y + yincr[i];
	    xend = x + xincr[i];
	    if (ONBOARD(xend, yend)
		&& IS_SHIP(board[b][xend][yend])) {
		collide = TRUE;
		break;
	    }
	}
    }
    return (collide);
}

static bool
checkplace(int b, ship_t * ss, int vis)
{
    int l, xend, yend;

    /* first, check for board edges */
    xend = ss->x + (ss->length - 1) * xincr[ss->dir];
    yend = ss->y + (ss->length - 1) * yincr[ss->dir];
    if (!ONBOARD(xend, yend)) {
	if (vis)
	    switch (rnd(3)) {
	    case 0:
		error("Ship is hanging from the edge of the world");
		break;
	    case 1:
		error("Try fitting it on the board");
		break;
	    case 2:
		error("Figure I won't find it if you put it there?");
		break;
	    }
	return (FALSE);
    }

    for (l = 0; l < ss->length; ++l) {
	if (collidecheck(b, ss->y + l * yincr[ss->dir], ss->x + l * xincr[ss->dir])) {
	    if (vis)
		switch (rnd(3)) {
		case 0:
		    error("There's already a ship there");
		    break;
		case 1:
		    error("Collision alert!  Aaaaaagh!");
		    break;
		case 2:
		    error("Er, Admiral, what about the other ship?");
		    break;
		}
	    return (FALSE);
	}
    }
    return (TRUE);
}

static int
awinna(void)
{
    int i, j;
    ship_t *ss;

    for (i = 0; i < 2; ++i) {
	ss = (i) ? cpuship : plyship;
	for (j = 0; j < SHIPTYPES; ++j, ++ss)
	    if (ss->length > ss->hits)
		break;
	if (j == SHIPTYPES)
	    return (OTHER);
    }
    return (-1);
}

static ship_t *
hitship(int x, int y)
/* register a hit on the targeted ship */
{
    ship_t *sb, *ss;
    char sym;
    int oldx, oldy;

    getyx(stdscr, oldy, oldx);
    sb = (turn) ? plyship : cpuship;
    if ((sym = board[OTHER][x][y]) == 0)
	return ((ship_t *) NULL);
    for (ss = sb; ss < sb + SHIPTYPES; ++ss)
	if (ss->symbol == sym) {
	    if (++ss->hits < ss->length)	/* still afloat? */
		return ((ship_t *) NULL);
	    else {		/* sunk! */
		int i, j;

		if (!closepack)
		    for (j = -1; j <= 1; j++) {
			int bx = ss->x + j * xincr[(ss->dir + 2) % 8];
			int by = ss->y + j * yincr[(ss->dir + 2) % 8];

			for (i = -1; i <= ss->length; ++i) {
			    int x1, y1;

			    x1 = bx + i * xincr[ss->dir];
			    y1 = by + i * yincr[ss->dir];
			    if (ONBOARD(x1, y1)) {
				hits[turn][x1][y1] = MARK_MISS;
				if (turn % 2 == PLAYER) {
				    cgoto(y1, x1);
#ifdef A_COLOR
				    if (has_colors())
					attron(COLOR_PAIR(COLOR_GREEN));
#endif /* A_COLOR */
				    (void) addch(MARK_MISS);
#ifdef A_COLOR
				    attrset(0);
#endif /* A_COLOR */
				} else {
				    pgoto(y1, x1);
				    (void) addch(SHOWSPLASH);
				}
			    }
			}
		    }

		for (i = 0; i < ss->length; ++i) {
		    int x1 = ss->x + i * xincr[ss->dir];
		    int y1 = ss->y + i * yincr[ss->dir];

		    hits[turn][x1][y1] = ss->symbol;
		    if (turn % 2 == PLAYER) {
			cgoto(y1, x1);
			(void) addch((chtype) (ss->symbol));
		    } else {
			pgoto(y1, x1);
#ifdef A_COLOR
			if (has_colors())
			    attron(COLOR_PAIR(COLOR_RED));
#endif /* A_COLOR */
			(void) addch(SHOWHIT);
#ifdef A_COLOR
			attrset(0);
#endif /* A_COLOR */
		    }
		}

		(void) move(oldy, oldx);
		return (ss);
	    }
	}
    (void) move(oldy, oldx);
    return ((ship_t *) NULL);
}

static bool
plyturn(void)
{
    ship_t *ss;
    bool hit;
    NCURSES_CONST char *m = NULL;

    prompt(1, "Where do you want to shoot? ", "");
    for (;;) {
	(void) getcoord(COMPUTER);
	if (hits[PLAYER][curx][cury]) {
	    prompt(1, "You shelled this spot already! Try again.", "");
	    beep();
	} else
	    break;
    }
    hit = IS_SHIP(board[COMPUTER][curx][cury]);
    hits[PLAYER][curx][cury] = (hit ? MARK_HIT : MARK_MISS);
    cgoto(cury, curx);
#ifdef A_COLOR
    if (has_colors()) {
	if (hit)
	    attron(COLOR_PAIR(COLOR_RED));
	else
	    attron(COLOR_PAIR(COLOR_GREEN));
    }
#endif /* A_COLOR */
    (void) addch((chtype) hits[PLAYER][curx][cury]);
#ifdef A_COLOR
    attrset(0);
#endif /* A_COLOR */

    prompt(1, "You %s.", hit ? "scored a hit" : "missed");
    if (hit && (ss = hitship(curx, cury))) {
	switch (rnd(5)) {
	case 0:
	    m = " You sank my %s!";
	    break;
	case 1:
	    m = " I have this sinking feeling about my %s....";
	    break;
	case 2:
	    m = " My %s has gone to Davy Jones's locker!";
	    break;
	case 3:
	    m = " Glub, glub -- my %s is headed for the bottom!";
	    break;
	case 4:
	    m = " You'll pick up survivors from my %s, I hope...!";
	    break;
	}
	(void) printw(m, ss->name);
	(void) beep();
	return (awinna() == -1);
    }
    return (hit);
}

static int
sgetc(const char *s)
{
    const char *s1;
    int ch;

    (void) refresh();
    for (;;) {
	ch = getch();
	if (islower(ch))
	    ch = toupper(ch);
	if (ch == CTRLC)
	    uninitgame(0);
	for (s1 = s; *s1 && ch != *s1; ++s1)
	    continue;
	if (*s1) {
	    (void) addch((chtype) ch);
	    (void) refresh();
	    return (ch);
	}
    }
}

static void
randomfire(int *px, int *py)
/* random-fire routine -- implements simple diagonal-striping strategy */
{
    static int turncount = 0;
    static int srchstep = BEGINSTEP;
    static int huntoffs;	/* Offset on search strategy */
    int ypossible[BWIDTH * BDEPTH], xpossible[BWIDTH * BDEPTH], nposs;
    int ypreferred[BWIDTH * BDEPTH], xpreferred[BWIDTH * BDEPTH], npref;
    int x, y, i;

    if (turncount++ == 0)
	huntoffs = rnd(srchstep);

    /* first, list all possible moves */
    nposs = npref = 0;
    for (x = 0; x < BWIDTH; x++)
	for (y = 0; y < BDEPTH; y++)
	    if (!hits[COMPUTER][x][y]) {
		xpossible[nposs] = x;
		ypossible[nposs] = y;
		nposs++;
		if (((x + huntoffs) % srchstep) != (y % srchstep)) {
		    xpreferred[npref] = x;
		    ypreferred[npref] = y;
		    npref++;
		}
	    }

    if (npref) {
	i = rnd(npref);

	*px = xpreferred[i];
	*py = ypreferred[i];
    } else if (nposs) {
	i = rnd(nposs);

	*px = xpossible[i];
	*py = ypossible[i];

	if (srchstep > 1)
	    --srchstep;
    } else {
	error("No moves possible?? Help!");
	ExitProgram(EXIT_FAILURE);
	/*NOTREACHED */
    }
}

#define S_MISS	0
#define S_HIT	1
#define S_SUNK	-1

static int
cpufire(int x, int y)
/* fire away at given location */
{
    bool hit, sunk;
    ship_t *ss = NULL;

    hits[COMPUTER][x][y] = (hit = (board[PLAYER][x][y])) ? MARK_HIT : MARK_MISS;
    (void) mvprintw(PROMPTLINE, 0,
		    "I shoot at %c%d. I %s!", y + 'A', x, hit ? "hit" :
		    "miss");
    if ((sunk = (hit && (ss = hitship(x, y)))) != 0)
	(void) printw(" I've sunk your %s", ss->name);
    (void) clrtoeol();

    pgoto(y, x);
#ifdef A_COLOR
    if (has_colors()) {
	if (hit)
	    attron(COLOR_PAIR(COLOR_RED));
	else
	    attron(COLOR_PAIR(COLOR_GREEN));
    }
#endif /* A_COLOR */
    (void) addch((chtype) (hit ? SHOWHIT : SHOWSPLASH));
#ifdef A_COLOR
    attrset(0);
#endif /* A_COLOR */

    return ((hit ? (sunk ? S_SUNK : S_HIT) : S_MISS) ? TRUE : FALSE);
}

/*
 * This code implements a fairly irregular FSM, so please forgive the rampant
 * unstructuredness below. The five labels are states which need to be held
 * between computer turns.
 */
static bool
cputurn(void)
{
#define POSSIBLE(x, y)	(ONBOARD(x, y) && !hits[COMPUTER][x][y])
#define RANDOM_FIRE	0
#define RANDOM_HIT	1
#define HUNT_DIRECT	2
#define FIRST_PASS	3
#define REVERSE_JUMP	4
#define SECOND_PASS	5
    static int next = RANDOM_FIRE;
    static bool used[4];
    static ship_t ts;
    int navail, x, y, d, n;
    int hit = S_MISS;

    switch (next) {
    case RANDOM_FIRE:		/* last shot was random and missed */
      refire:
	randomfire(&x, &y);
	if (!(hit = cpufire(x, y)))
	    next = RANDOM_FIRE;
	else {
	    ts.x = x;
	    ts.y = y;
	    ts.hits = 1;
	    next = (hit == S_SUNK) ? RANDOM_FIRE : RANDOM_HIT;
	}
	break;

    case RANDOM_HIT:		/* last shot was random and hit */
	used[E / 2] = used[S / 2] = used[W / 2] = used[N / 2] = FALSE;
	/* FALLTHROUGH */

    case HUNT_DIRECT:		/* last shot hit, we're looking for ship's long axis */
	for (d = navail = 0; d < 4; d++) {
	    x = ts.x + xincr[d * 2];
	    y = ts.y + yincr[d * 2];
	    if (!used[d] && POSSIBLE(x, y))
		navail++;
	    else
		used[d] = TRUE;
	}
	if (navail == 0)	/* no valid places for shots adjacent... */
	    goto refire;	/* ...so we must random-fire */
	else {
	    for (d = 0, n = rnd(navail) + 1; n; n--)
		while (used[d])
		    d++;

	    assert(d <= 4);

	    used[d] = FALSE;
	    x = ts.x + xincr[d * 2];
	    y = ts.y + yincr[d * 2];

	    assert(POSSIBLE(x, y));

	    if (!(hit = cpufire(x, y)))
		next = HUNT_DIRECT;
	    else {
		ts.x = x;
		ts.y = y;
		ts.dir = d * 2;
		ts.hits++;
		next = (hit == S_SUNK) ? RANDOM_FIRE : FIRST_PASS;
	    }
	}
	break;

    case FIRST_PASS:		/* we have a start and a direction now */
	x = ts.x + xincr[ts.dir];
	y = ts.y + yincr[ts.dir];
	if (POSSIBLE(x, y) && (hit = cpufire(x, y))) {
	    ts.x = x;
	    ts.y = y;
	    ts.hits++;
	    next = (hit == S_SUNK) ? RANDOM_FIRE : FIRST_PASS;
	} else
	    next = REVERSE_JUMP;
	break;

    case REVERSE_JUMP:		/* nail down the ship's other end */
	d = ts.dir + 4;
	x = ts.x + ts.hits * xincr[d];
	y = ts.y + ts.hits * yincr[d];
	if (POSSIBLE(x, y) && (hit = cpufire(x, y))) {
	    ts.x = x;
	    ts.y = y;
	    ts.dir = d;
	    ts.hits++;
	    next = (hit == S_SUNK) ? RANDOM_FIRE : SECOND_PASS;
	} else
	    next = RANDOM_FIRE;
	break;

    case SECOND_PASS:		/* kill squares not caught on first pass */
	x = ts.x + xincr[ts.dir];
	y = ts.y + yincr[ts.dir];
	if (POSSIBLE(x, y) && (hit = cpufire(x, y))) {
	    ts.x = x;
	    ts.y = y;
	    ts.hits++;
	    next = (hit == S_SUNK) ? RANDOM_FIRE : SECOND_PASS;
	    break;
	} else
	    next = RANDOM_FIRE;
	break;
    }

    /* check for continuation and/or winner */
    if (salvo) {
	(void) refresh();
	(void) sleep(1);
    }
    if (awinna() != -1)
	return (FALSE);

#ifdef DEBUG
    (void) mvprintw(PROMPTLINE + 2, 0,
		    "New state %d, x=%d, y=%d, d=%d",
		    next, x, y, d);
#endif /* DEBUG */
    return ((hit) ? TRUE : FALSE);
}

static int
playagain(void)
{
    int j;
    ship_t *ss;

    for (ss = cpuship; ss < cpuship + SHIPTYPES; ss++)
	for (j = 0; j < ss->length; j++) {
	    cgoto(ss->y + j * yincr[ss->dir], ss->x + j * xincr[ss->dir]);
	    (void) addch((chtype) ss->symbol);
	}

    if (awinna())
	++cpuwon;
    else
	++plywon;
    j = 18 + strlen(name);
    if (plywon >= 10)
	++j;
    if (cpuwon >= 10)
	++j;
    (void) mvprintw(1, (COLWIDTH - j) / 2,
		    "%s: %d     Computer: %d", name, plywon, cpuwon);

    prompt(2, (awinna())? "Want to be humiliated again, %s [yn]? "
	   : "Going to give me a chance for revenge, %s [yn]? ", name);
    return (sgetc("YN") == 'Y');
}

static void
do_options(int c, char *op[])
{
    register int i;

    if (c > 1) {
	for (i = 1; i < c; i++) {
	    switch (op[i][0]) {
	    default:
	    case '?':
		(void) fprintf(stderr, "Usage: battle [-s | -b] [-c]\n");
		(void) fprintf(stderr, "\tWhere the options are:\n");
		(void) fprintf(stderr, "\t-s : play a salvo game\n");
		(void) fprintf(stderr, "\t-b : play a blitz game\n");
		(void) fprintf(stderr, "\t-c : ships may be adjacent\n");
		ExitProgram(EXIT_FAILURE);
		break;
	    case '-':
		switch (op[i][1]) {
		case 'b':
		    blitz = 1;
		    if (salvo == 1) {
			(void) fprintf(stderr,
				       "Bad Arg: -b and -s are mutually exclusive\n");
			ExitProgram(EXIT_FAILURE);
		    }
		    break;
		case 's':
		    salvo = 1;
		    if (blitz == 1) {
			(void) fprintf(stderr,
				       "Bad Arg: -s and -b are mutually exclusive\n");
			ExitProgram(EXIT_FAILURE);
		    }
		    break;
		case 'c':
		    closepack = 1;
		    break;
		default:
		    (void) fprintf(stderr,
				   "Bad arg: type \"%s ?\" for usage message\n",
				   op[0]);
		    ExitProgram(EXIT_FAILURE);
		}
	    }
	}
    }
}

static int
scount(int who)
{
    register int i, shots;
    register ship_t *sp;

    if (who)
	sp = cpuship;		/* count cpu shots */
    else
	sp = plyship;		/* count player shots */

    for (i = 0, shots = 0; i < SHIPTYPES; i++, sp++) {
	if (sp->hits >= sp->length)
	    continue;		/* dead ship */
	else
	    shots++;
    }
    return (shots);
}

int
main(int argc, char *argv[])
{
    setlocale(LC_ALL, "");

    do_options(argc, argv);

    intro();
    do {
	initgame();
	while (awinna() == -1) {
	    if (!blitz) {
		if (!salvo) {
		    if (turn)
			(void) cputurn();
		    else
			(void) plyturn();
		} else {
		    register int i;

		    i = scount(turn);
		    while (i--) {
			if (turn) {
			    if (cputurn() && awinna() != -1)
				i = 0;
			} else {
			    if (plyturn() && awinna() != -1)
				i = 0;
			}
		    }
		}
	    } else
		while (turn ? cputurn() : plyturn())
		    continue;
	    turn = OTHER;
	}
    } while
	(playagain());
    uninitgame(0);
    /*NOTREACHED */
}

/* bs.c ends here */