Mercurial > hg > terminal-chess / file revision
src/game.c@7ffd66591afe
src/game.c
Fri, 28 Mar 2014 11:45:01 +0100
- author
- Mike Becker <universe@uap-core.de>
- date
- Fri, 28 Mar 2014 11:45:01 +0100
- changeset 15
- 7ffd66591afe
- parent 14
- 970748b9a73b
- child 16
- a298c6637c30
- permissions
- -rw-r--r--
completed pawn rules + bug fixes for 4-char-moves
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2014 Mike Becker. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 *
28 */
30 #include "game.h"
31 #include "input.h"
32 #include "rules/rules.h"
33 #include <ncurses.h>
34 #include <string.h>
36 static const uint8_t boardx = 10, boardy = 10;
38 static void draw_board(Board board, uint8_t mycolor) {
40 for (uint8_t y = 0 ; y < 8 ; y++) {
41 for (uint8_t x = 0 ; x < 8 ; x++) {
42 uint8_t col = board[y][x] & COLOR_MASK;
43 uint8_t piece = board[y][x] & PIECE_MASK;
44 char piecec = ' ';
45 switch (piece) {
46 case PAWN: piecec = 'P'; break;
47 case ROOK: piecec = 'R'; break;
48 case KNIGHT: piecec = 'N'; break;
49 case BISHOP: piecec = 'B'; break;
50 case QUEEN: piecec = 'Q'; break;
51 case KING: piecec = 'K'; break;
52 }
54 attrset((col == WHITE ? A_BOLD : A_DIM) |
55 COLOR_PAIR((y&1)==(x&1) ? COL_WB : COL_BW));
57 int cy = mycolor == WHITE ? boardy-y : boardy-7+y;
58 int cx = mycolor == WHITE ? boardx+x*3 : boardx+21-x*3;
59 mvaddch(cy, cx, ' ');
60 mvaddch(cy, cx+1, piecec);
61 mvaddch(cy, cx+2, ' ');
62 }
63 }
65 attrset(A_NORMAL);
66 for (uint8_t i = 0 ; i < 8 ; i++) {
67 int x = mycolor == WHITE ? boardx+i*3+1 : boardx+22-i*3;
68 int y = mycolor == WHITE ? boardy-i : boardy-7+i;
69 mvaddch(boardy+1, x, 'a'+i);
70 mvaddch(y, boardx-2, '1'+i);
71 }
72 }
74 /**
75 * Applies a move and deletes captured pieces.
76 *
77 * @param board the current board state
78 * @param move the move to apply
79 */
80 static void apply_move(Board board, Move *move) {
81 uint8_t piece = move->piece & PIECE_MASK;
82 uint8_t color = move->piece & COLOR_MASK;
84 /* en passant capture */
85 if (move->capture && piece == PAWN &&
86 mdst(board, move) == 0) {
87 board[move->fromrow][move->tofile] = 0;
88 }
90 /* remove old en passant threats */
91 for (uint8_t file = 0 ; file < 8 ; file++) {
92 board[3][file] &= ~ENPASSANT_THREAT;
93 board[4][file] &= ~ENPASSANT_THREAT;
94 }
96 /* add new en passant threat */
97 if (piece == PAWN && (
98 (move->fromrow == 1 && move->torow == 3) ||
99 (move->fromrow == 6 && move->torow == 4))) {
100 move->piece |= ENPASSANT_THREAT;
101 }
103 /* move (and maybe capture) */
104 msrc(board, move) = 0;
105 mdst(board, move) = move->piece;
107 /* castling */
108 if (piece == KING &&
109 move->fromfile == fileidx('e')) {
111 if (move->tofile == fileidx('g')) {
112 board[move->torow][fileidx('h')] = 0;
113 board[move->torow][fileidx('f')] = color|ROOK;
114 } else if (move->tofile == fileidx('c')) {
115 board[move->torow][fileidx('a')] = 0;
116 board[move->torow][fileidx('d')] = color|ROOK;
117 }
118 }
119 }
121 /**
122 * Validates move by applying chess rules.
123 * @param board the current board state
124 * @param move the move to validate
125 * @return TRUE, if the move complies to chess rules, FALSE otherwise
126 */
127 static _Bool validate_move(Board board, Move *move) {
128 _Bool result;
130 /* validate indices (don't trust opponent) */
131 if (!chkidx(move)) {
132 return FALSE;
133 }
135 /* does piece exist */
136 result = msrc(board, move) == move->piece;
138 /* can't capture own pieces */
139 if ((mdst(board, move) & COLOR_MASK) == (move->piece & COLOR_MASK)) {
140 return FALSE;
141 }
143 /* validate individual rules */
144 switch (move->piece & PIECE_MASK) {
145 case PAWN:
146 result = result && pawn_chkrules(board, move);
147 result = result && !pawn_isblocked(board, move);
148 break;
149 case ROOK:
150 result = result && rook_chkrules(board, move);
151 result = result && !rook_isblocked(board, move);
152 break;
153 case KNIGHT:
154 result = result && knight_chkrules(board, move);
155 result = result && !knight_isblocked(board, move);
156 break;
157 case BISHOP:
158 result = result && bishop_chkrules(board, move);
159 result = result && !bishop_isblocked(board, move);
160 break;
161 case QUEEN:
162 result = result && queen_chkrules(board, move);
163 result = result && !queen_isblocked(board, move);
164 break;
165 case KING:
166 result = result && king_chkrules(board, move);
167 result = result && !king_isblocked(board, move);
168 break;
169 default:
170 result = FALSE;
171 }
173 /* is piece pinned */
174 // TODO: make it so
176 /* correct check and checkmate flags */
177 // TODO: make it so
179 return result;
180 }
182 /**
183 * Maps a character to a piece.
184 *
185 * Does not work for pawns, since they don't have a character.
186 *
187 * @param c one of R,N,B,Q,K
188 * @return numeric value for the specified piece
189 */
190 static uint8_t getpiece(char c) {
191 switch (c) {
192 case 'R': return ROOK;
193 case 'N': return KNIGHT;
194 case 'B': return BISHOP;
195 case 'Q': return QUEEN;
196 case 'K': return KING;
197 default: return 0;
198 }
199 }
201 /**
202 * Guesses the location of a piece for short algebraic notation.
203 *
204 * @param board the current state of the board
205 * @param move the move date to operate on
206 * @return TRUE if the location could be retrieved, FALSE if the location is
207 * ambiguous
208 */
209 static _Bool getlocation(Board board, Move *move) {
210 uint8_t piece = move->piece & PIECE_MASK;
211 switch (piece) {
212 case PAWN: return pawn_getlocation(board, move);
213 case ROOK: return rook_getlocation(board, move);
214 case KNIGHT: return knight_getlocation(board, move);
215 case BISHOP: return bishop_getlocation(board, move);
216 case QUEEN: return queen_getlocation(board, move);
217 case KING: return king_getlocation(board, move);
218 default: return FALSE;
219 }
220 }
222 /**
223 * Evaluates a move syntactically and stores the move data in the specified
224 * object.
225 *
226 * @param board the current state of the board
227 * @param mycolor the color of the current player
228 * @param mstr the input string to parse
229 * @param move a pointer to object where the move data shall be stored
230 * @return TRUE, if the move is syntactically valid, FALSE otherwise
231 */
232 static _Bool eval_move(Board board, uint8_t mycolor, char *mstr, Move *move) {
233 memset(move, 0, sizeof(Move));
234 move->fromfile = POS_UNSPECIFIED;
235 move->fromrow = POS_UNSPECIFIED;
237 size_t len = strlen(mstr);
239 /* evaluate check/checkmate flags */
240 if (mstr[len-1] == '+') {
241 len--; mstr[len] = '\0';
242 move->check = TRUE;
243 } else if (mstr[len-1] == '#') {
244 len--; mstr[len] = '\0';
245 move->checkmate = TRUE;
246 }
248 if (len == 2) {
249 /* pawn move (e.g. "e4") */
250 move->piece = PAWN;
251 move->tofile = fileidx(mstr[0]);
252 move->torow = rowidx(mstr[1]);
253 } else if (len == 3) {
254 if (strcmp(mstr, "O-O") == 0) {
255 /* king side castling */
256 move->piece = KING;
257 move->fromfile = fileidx('e');
258 move->tofile = fileidx('g');
259 move->fromrow = move->torow = mycolor == WHITE ? 0 : 7;
260 } else {
261 /* move (e.g. "Nf3") */
262 move->piece = getpiece(mstr[0]);
263 move->tofile = fileidx(mstr[1]);
264 move->torow = rowidx(mstr[2]);
265 }
267 } else if (len == 4) {
268 move->piece = getpiece(mstr[0]);
269 if (!move->piece) {
270 move->piece = PAWN;
271 move->fromfile = fileidx(mstr[0]);
272 }
273 if (mstr[1] == 'x') {
274 /* capture (e.g. "Nxf3", "dxe5") */
275 move->capture = TRUE;
276 } else {
277 /* move (e.g. "Ndf3", "N2c3", "e2e4") */
278 if (isfile(mstr[1])) {
279 move->fromfile = fileidx(mstr[1]);
280 if (move->piece == PAWN) {
281 move->piece = 0;
282 }
283 } else {
284 move->fromrow = rowidx(mstr[1]);
285 }
286 }
287 move->tofile = fileidx(mstr[2]);
288 move->torow = rowidx(mstr[3]);
289 } else if (len == 5) {
290 if (strcmp(mstr, "O-O-O") == 0) {
291 /* queen side castling "O-O-O" */
292 move->piece = KING;
293 move->fromfile = fileidx('e');
294 move->tofile = fileidx('c');
295 move->fromrow = move->torow = mycolor == WHITE ? 0 : 7;
296 } else {
297 move->piece = getpiece(mstr[0]);
298 if (mstr[2] == 'x') {
299 move->capture = TRUE;
300 if (move->piece) {
301 /* capture (e.g. "Ndxf3") */
302 move->fromfile = fileidx(mstr[1]);
303 } else {
304 /* long notation capture (e.g. "e5xf6") */
305 move->piece = PAWN;
306 move->fromfile = fileidx(mstr[0]);
307 move->fromrow = rowidx(mstr[1]);
308 }
309 } else {
310 /* long notation move (e.g. "Nc5a4") */
311 move->fromfile = fileidx(mstr[1]);
312 move->fromrow = rowidx(mstr[2]);
313 }
314 move->tofile = fileidx(mstr[3]);
315 move->torow = rowidx(mstr[4]);
316 }
317 } else if (len == 6) {
318 /* long notation capture (e.g. "Nc5xf3") */
319 if (mstr[3] == 'x') {
320 move->capture = TRUE;
321 move->piece = getpiece(mstr[0]);
322 move->fromfile = fileidx(mstr[1]);
323 move->fromrow = rowidx(mstr[2]);
324 move->tofile = fileidx(mstr[4]);
325 move->torow = rowidx(mstr[5]);
326 }
327 }
330 if (move->piece) {
331 move->piece |= mycolor;
332 if (move->fromfile == POS_UNSPECIFIED
333 || move->fromrow == POS_UNSPECIFIED) {
334 return getlocation(board, move) && chkidx(move);
335 } else {
336 return chkidx(move);
337 }
338 } else {
339 return FALSE;
340 }
341 // TODO: return status code to indicate the error type
342 }
344 static int sendmove(Board board, uint8_t mycolor, int opponent) {
345 const size_t buflen = 8;
346 char movestr[buflen];
347 _Bool remisrejected = FALSE;
348 uint8_t code;
350 while (1) {
351 move(boardy+3, 0);
352 if (remisrejected) {
353 printw(
354 "Use chess notation to enter your move.\n"
355 "Remis offer rejected - type 'surr' to surrender. \n\n"
356 "Type your move: ");
357 } else {
358 printw(
359 "Use chess notation to enter your move.\n"
360 "Or type 'surr' to surrender or 'remis' to offer remis.\n\n"
361 "Type your move: ");
362 }
363 clrtoeol();
364 refresh();
365 getnstr(movestr, buflen);
367 if (strncmp(movestr, "surr", buflen) == 0) {
368 printw("You surrendered!");
369 refresh();
370 net_send_code(opponent, NETCODE_SURRENDER);
371 return 1;
372 } else if (strncmp(movestr, "remis", buflen) == 0) {
373 if (!remisrejected) {
374 net_send_code(opponent, NETCODE_REMIS);
375 printw("Remis offer sent - waiting for acceptance...");
376 refresh();
377 if (net_recieve_code(opponent) == NETCODE_ACCEPT) {
378 printw("\rRemis accepted!");
379 clrtoeol();
380 refresh();
381 return 1;
382 } else {
383 remisrejected = TRUE;
384 }
385 }
386 } else {
387 Move move;
388 if (eval_move(board, mycolor, movestr, &move)) {
389 net_send_code(opponent, NETCODE_MOVE);
390 net_send_data(opponent, &move, sizeof(Move));
391 code = net_recieve_code(opponent);
392 move.check = code == NETCODE_CHECK;
393 move.checkmate = code == NETCODE_CHECKMATE;
394 // TODO: record move
395 if (code == NETCODE_DECLINE) {
396 printw("Invalid move.");
397 clrtoeol();
398 } else {
399 apply_move(board, &move);
400 if (move.checkmate) {
401 printw("Checkmate!");
402 return 1;
403 } else {
404 return 0;
405 }
406 }
407 } else {
408 printw("Can't interpret move - please use algebraic notation.");
409 }
410 }
411 }
412 }
414 static int recvmove(Board board, int opponent) {
416 while (1) {
417 move(boardy+3, 0);
418 printw("Awaiting opponent move...");
419 clrtoeol();
420 refresh();
422 // TODO: nonblocking
423 uint32_t code = net_recieve_code(opponent);
425 Move move;
426 switch (code) {
427 case NETCODE_SURRENDER:
428 printw("\rYour opponent surrendered!");
429 clrtoeol();
430 return 1;
431 case NETCODE_REMIS:
432 if (prompt_yesno(
433 "\rYour opponent offers remis - do you accept")) {
434 printw("\rRemis accepted!");
435 clrtoeol();
436 net_send_code(opponent, NETCODE_ACCEPT);
437 return 1;
438 } else {
439 net_send_code(opponent, NETCODE_DECLINE);
440 }
441 break;
442 case NETCODE_MOVE:
443 net_recieve_data(opponent, &move, sizeof(Move));
444 if (validate_move(board, &move)) {
445 apply_move(board, &move);
446 // TODO: record move
447 if (move.check) {
448 net_send_code(opponent, NETCODE_CHECK);
449 } else if (move.checkmate) {
450 net_send_code(opponent, NETCODE_CHECKMATE);
451 } else {
452 net_send_code(opponent, NETCODE_ACCEPT);
453 }
454 return 0;
455 } else {
456 net_send_code(opponent, NETCODE_DECLINE);
457 }
458 }
459 }
460 }
462 void game_start(Settings *settings, int opponent) {
463 _Bool myturn = is_server(settings) ==
464 (settings->gameinfo.servercolor == WHITE);
465 uint8_t mycolor = myturn ? WHITE:BLACK;
467 _Bool running;
469 Board board = {
470 {WROOK, WKNIGHT, WBISHOP, WQUEEN, WKING, WBISHOP, WKNIGHT, WROOK},
471 {WPAWN, WPAWN, WPAWN, WPAWN, WPAWN, WPAWN, WPAWN, WPAWN},
472 {0, 0, 0, 0, 0, 0, 0, 0},
473 {0, 0, 0, 0, 0, 0, 0, 0},
474 {0, 0, 0, 0, 0, 0, 0, 0},
475 {0, 0, 0, 0, 0, 0, 0, 0},
476 {BPAWN, BPAWN, BPAWN, BPAWN, BPAWN, BPAWN, BPAWN, BPAWN},
477 {BROOK, BKNIGHT, BBISHOP, BQUEEN, BKING, BBISHOP, BKNIGHT, BROOK}
478 };
480 do {
481 clear();
482 draw_board(board, mycolor);
483 if (myturn) {
484 running = !sendmove(board, mycolor, opponent);
485 } else {
486 running = !recvmove(board, opponent);
487 flushinp(); // flush any input the user hacked in while waiting
488 }
489 myturn ^= TRUE;
490 } while (running);
492 mvaddstr(getmaxy(tchess_window)-1, 0,
493 "Game has ended. Press any key to leave...");
494 getch();
495 }
