xref: /dragonfly/games/cribbage/support.c (revision 73610d44)
1 /*-
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)support.c	8.1 (Berkeley) 5/31/93
30  * $FreeBSD: src/games/cribbage/support.c,v 1.5 1999/12/12 03:04:15 billf Exp $
31  * $DragonFly: src/games/cribbage/support.c,v 1.3 2005/08/03 13:31:00 eirikn Exp $
32  */
33 
34 #include <curses.h>
35 #include <stdio.h>
36 #include <string.h>
37 
38 #include "deck.h"
39 #include "cribbage.h"
40 #include "cribcur.h"
41 
42 #define	NTV	10		/* number scores to test */
43 
44 /* score to test reachability of, and order to test them in */
45 const int tv[NTV] = {8, 7, 9, 6, 11, 12, 13, 14, 10, 5};
46 
47 static int anysumto(CARD[], int, int, int);
48 static int numofval(CARD[], int, int);
49 static void prpeg(int, int, bool);
50 
51 /*
52  * computer chooses what to play in pegging...
53  * only called if no playable card will score points
54  */
55 int
56 cchose(CARD h[], int n, int s)
57 {
58 	int i, j, l;
59 
60 	if (n <= 1)
61 		return (0);
62 	if (s < 4) {		/* try for good value */
63 		if ((j = anysumto(h, n, s, 4)) >= 0)
64 			return (j);
65 		if ((j = anysumto(h, n, s, 3)) >= 0 && s == 0)
66 			return (j);
67 	}
68 	if (s > 0 && s < 20) {
69 				/* try for retaliation to 31 */
70 		for (i = 1; i <= 10; i++) {
71 			if ((j = anysumto(h, n, s, 21 - i)) >= 0) {
72 				if ((l = numofval(h, n, i)) > 0) {
73 					if (l > 1 || VAL(h[j].rank) != i)
74 						return (j);
75 				}
76 			}
77 		}
78 	}
79 	if (s < 15) {
80 				/* for retaliation after 15 */
81 		for (i = 0; i < NTV; i++) {
82 			if ((j = anysumto(h, n, s, tv[i])) >= 0) {
83 				if ((l = numofval(h, n, 15 - tv[i])) > 0) {
84 					if (l > 1 ||
85 					    VAL(h[j].rank) != 15 - tv[i])
86 						return (j);
87 				}
88 			}
89 		}
90 	}
91 	j = -1;
92 				/* remember: h is sorted */
93 	for (i = n - 1; i >= 0; --i) {
94 		l = s + VAL(h[i].rank);
95 		if (l > 31)
96 			continue;
97 		if (l != 5 && l != 10 && l != 21) {
98 			j = i;
99 			break;
100 		}
101 	}
102 	if (j >= 0)
103 		return (j);
104 	for (i = n - 1; i >= 0; --i) {
105 		l = s + VAL(h[i].rank);
106 		if (l > 31)
107 			continue;
108 		if (j < 0)
109 			j = i;
110 		if (l != 5 && l != 21) {
111 			j = i;
112 			break;
113 		}
114 	}
115 	return (j);
116 }
117 
118 /*
119  * plyrhand:
120  *	Evaluate and score a player hand or crib
121  */
122 bool
123 plyrhand(CARD hand[], const char *s)
124 {
125 	static char prompt[BUFSIZ];
126 	int i, j;
127 	bool win;
128 
129 	prhand(hand, CINHAND, Playwin, false);
130 	sprintf(prompt, "Your %s scores ", s);
131 	i = scorehand(hand, turnover, CINHAND, strcmp(s, "crib") == 0, explain);
132 	if ((j = number(0, 29, prompt)) == 19)
133 		j = 0;
134 	if (i != j) {
135 		if (i < j) {
136 			win = chkscr(&pscore, i);
137 			msg("It's really only %d points; I get %d", i, 2);
138 			if (!win)
139 				win = chkscr(&cscore, 2);
140 		} else {
141 			win = chkscr(&pscore, j);
142 			msg("You should have taken %d, not %d!", i, j);
143 		}
144 		if (explain)
145 			msg("Explanation: %s", explstr);
146 		do_wait();
147 	} else
148 		win = chkscr(&pscore, i);
149 	return (win);
150 }
151 
152 /*
153  * comphand:
154  *	Handle scoring and displaying the computer's hand
155  */
156 bool
157 comphand(CARD h[], const char *s)
158 {
159 	int j;
160 
161 	j = scorehand(h, turnover, CINHAND, strcmp(s, "crib") == 0, false);
162 	prhand(h, CINHAND, Compwin, false);
163 	msg("My %s scores %d", s, (j == 0 ? 19 : j));
164 	return (chkscr(&cscore, j));
165 }
166 
167 /*
168  * chkscr:
169  *	Add inc to scr and test for > glimit, printing on the scoring
170  *	board while we're at it.
171  */
172 int Lastscore[2] = {-1, -1};
173 
174 bool
175 chkscr(int *scr, int inc)
176 {
177 	bool myturn;
178 
179 	myturn = (scr == &cscore);
180 	if (inc != 0) {
181 		prpeg(Lastscore[myturn], '.', myturn);
182 		Lastscore[myturn] = *scr;
183 		*scr += inc;
184 		prpeg(*scr, PEG, myturn);
185 		refresh();
186 	}
187 	return (*scr >= glimit);
188 }
189 
190 /*
191  * prpeg:
192  *	Put out the peg character on the score board and put the
193  *	score up on the board.
194  */
195 static void
196 prpeg(int score, int peg, bool myturn)
197 {
198 	int y, x;
199 
200 	if (!myturn)
201 		y = SCORE_Y + 2;
202 	else
203 		y = SCORE_Y + 5;
204 
205 	if (score <= 0 || score >= glimit) {
206 		if (peg == '.')
207 			peg = ' ';
208 		if (score == 0)
209 			x = SCORE_X + 2;
210 		else {
211 			x = SCORE_X + 2;
212 			y++;
213 		}
214 	} else {
215 		x = (score - 1) % 30;
216 		if (score > 90 || (score > 30 && score <= 60)) {
217 			y++;
218 			x = 29 - x;
219 		}
220 		x += x / 5;
221 		x += SCORE_X + 3;
222 	}
223 	mvaddch(y, x, peg);
224 	mvprintw(SCORE_Y + (myturn ? 7 : 1), SCORE_X + 10, "%3d", score);
225 }
226 
227 /*
228  * cdiscard -- the computer figures out what is the best discard for
229  * the crib and puts the best two cards at the end
230  */
231 void
232 cdiscard(bool mycrib)
233 {
234 	CARD    d[CARDS], h[FULLHAND], cb[2];
235 	int i, j, k;
236 	int     nc, ns;
237 	long    sums[15];
238 	static int undo1[15] = {0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4};
239 	static int undo2[15] = {1, 2, 3, 4, 5, 2, 3, 4, 5, 3, 4, 5, 4, 5, 5};
240 
241 	makedeck(d);
242 	nc = CARDS;
243 	for (i = 0; i < knownum; i++) {	/* get all other cards */
244 		cremove(known[i], d, nc--);
245 	}
246 	for (i = 0; i < 15; i++)
247 		sums[i] = 0L;
248 	ns = 0;
249 	for (i = 0; i < (FULLHAND - 1); i++) {
250 		cb[0] = chand[i];
251 		for (j = i + 1; j < FULLHAND; j++) {
252 			cb[1] = chand[j];
253 			for (k = 0; k < FULLHAND; k++)
254 				h[k] = chand[k];
255 			cremove(chand[i], h, FULLHAND);
256 			cremove(chand[j], h, FULLHAND - 1);
257 			for (k = 0; k < nc; k++) {
258 				sums[ns] +=
259 				    scorehand(h, d[k], CINHAND, true, false);
260 				if (mycrib)
261 					sums[ns] += adjust(cb);
262 				else
263 					sums[ns] -= adjust(cb);
264 			}
265 			++ns;
266 		}
267 	}
268 	j = 0;
269 	for (i = 1; i < 15; i++)
270 		if (sums[i] > sums[j])
271 			j = i;
272 	for (k = 0; k < FULLHAND; k++)
273 		h[k] = chand[k];
274 	cremove(h[undo1[j]], chand, FULLHAND);
275 	cremove(h[undo2[j]], chand, FULLHAND - 1);
276 	chand[4] = h[undo1[j]];
277 	chand[5] = h[undo2[j]];
278 }
279 
280 /*
281  * returns true if some card in hand can be played without exceeding 31
282  */
283 bool
284 anymove(CARD hand[], int n, int sum)
285 {
286 	int i, j;
287 
288 	if (n < 1)
289 		return (false);
290 	j = hand[0].rank;
291 	for (i = 1; i < n; i++) {
292 		if (hand[i].rank < j)
293 			j = hand[i].rank;
294 	}
295 	return (sum + VAL(j) <= 31);
296 }
297 
298 /*
299  * anysumto returns the index (0 <= i < n) of the card in hand that brings
300  * the s up to t, or -1 if there is none
301  */
302 static int
303 anysumto(CARD hand[], int n, int s, int t)
304 {
305 	int i;
306 
307 	for (i = 0; i < n; i++) {
308 		if (s + VAL(hand[i].rank) == t)
309 			return (i);
310 	}
311 	return (-1);
312 }
313 
314 /*
315  * return the number of cards in h having the given rank value
316  */
317 static int
318 numofval(CARD h[], int n, int v)
319 {
320 	int i, j;
321 
322 	j = 0;
323 	for (i = 0; i < n; i++) {
324 		if (VAL(h[i].rank) == v)
325 			++j;
326 	}
327 	return (j);
328 }
329 
330 /*
331  * makeknown remembers all n cards in h for future recall
332  */
333 void
334 makeknown(CARD h[], int n)
335 {
336 	int i;
337 
338 	for (i = 0; i < n; i++)
339 		known[knownum++] = h[i];
340 }
341