1.1 --- a/src/chess/rules.c Thu Apr 17 12:16:14 2014 +0200
1.2 +++ b/src/chess/rules.c Wed May 28 15:47:57 2014 +0200
1.3 @@ -98,19 +98,6 @@
1.4 }
1.5 }
1.6
1.7 -static int getlocation(GameState *gamestate, Move *move) {
1.8 - uint8_t piece = move->piece & PIECE_MASK;
1.9 - switch (piece) {
1.10 - case PAWN: return pawn_getlocation(gamestate, move);
1.11 - case ROOK: return rook_getlocation(gamestate, move);
1.12 - case KNIGHT: return knight_getlocation(gamestate, move);
1.13 - case BISHOP: return bishop_getlocation(gamestate, move);
1.14 - case QUEEN: return queen_getlocation(gamestate, move);
1.15 - case KING: return king_getlocation(gamestate, move);
1.16 - default: return INVALID_MOVE_SYNTAX;
1.17 - }
1.18 -}
1.19 -
1.20 void apply_move(GameState *gamestate, Move *move) {
1.21 uint8_t piece = move->piece & PIECE_MASK;
1.22 uint8_t color = move->piece & COLOR_MASK;
1.23 @@ -170,13 +157,20 @@
1.24 }
1.25
1.26 /* does piece exist */
1.27 - if (msrc(gamestate->board, move) != move->piece) {
1.28 + if ((msrc(gamestate->board, move)&(PIECE_MASK|COLOR_MASK))
1.29 + != (move->piece&(PIECE_MASK|COLOR_MASK))) {
1.30 return 0;
1.31 }
1.32
1.33 /* can't capture own pieces */
1.34 if ((mdst(gamestate->board, move) & COLOR_MASK)
1.35 - == (move->piece & COLOR_MASK)) {
1.36 + == (move->piece & COLOR_MASK)) {
1.37 + return 0;
1.38 + }
1.39 +
1.40 + /* must capture, if and only if destination is occupied */
1.41 + if ((mdst(gamestate->board, move) == 0 && move->capture) ||
1.42 + (mdst(gamestate->board, move) != 0 && !move->capture)) {
1.43 return 0;
1.44 }
1.45
1.46 @@ -205,6 +199,7 @@
1.47 }
1.48
1.49 _Bool validate_move(GameState *gamestate, Move *move) {
1.50 + // TODO: provide more details via a return code
1.51
1.52 _Bool result = validate_move_rules(gamestate, move);
1.53
1.54 @@ -232,9 +227,9 @@
1.55 }
1.56
1.57 /* simulation move for check validation */
1.58 - GameState simulation;
1.59 - memcpy(&simulation, gamestate, sizeof(GameState));
1.60 - apply_move(&simulation, move);
1.61 + GameState simulation = *gamestate;
1.62 + Move simmove = *move;
1.63 + apply_move(&simulation, &simmove);
1.64
1.65 /* don't move into or stay in check position */
1.66 if (is_covered(&simulation, mykingrow, mykingfile,
1.67 @@ -323,6 +318,155 @@
1.68 return 1;
1.69 }
1.70
1.71 +_Bool get_threats(GameState *gamestate, uint8_t row, uint8_t file,
1.72 + uint8_t color, Move *threats, uint8_t *threatcount) {
1.73 + Move candidates[32];
1.74 + int candidatecount = 0;
1.75 + for (uint8_t r = 0 ; r < 8 ; r++) {
1.76 + for (uint8_t f = 0 ; f < 8 ; f++) {
1.77 + if ((gamestate->board[r][f] & COLOR_MASK) == color) {
1.78 + // non-capturing move
1.79 + memset(&(candidates[candidatecount]), 0, sizeof(Move));
1.80 + candidates[candidatecount].piece = gamestate->board[r][f];
1.81 + candidates[candidatecount].fromrow = r;
1.82 + candidates[candidatecount].fromfile = f;
1.83 + candidates[candidatecount].torow = row;
1.84 + candidates[candidatecount].tofile = file;
1.85 + candidatecount++;
1.86 +
1.87 + // capturing move
1.88 + memcpy(&(candidates[candidatecount]),
1.89 + &(candidates[candidatecount-1]), sizeof(Move));
1.90 + candidates[candidatecount].capture = 1;
1.91 + candidatecount++;
1.92 + }
1.93 + }
1.94 + }
1.95 +
1.96 + if (threatcount) {
1.97 + *threatcount = 0;
1.98 + }
1.99 +
1.100 +
1.101 + _Bool result = 0;
1.102 +
1.103 + for (int i = 0 ; i < candidatecount ; i++) {
1.104 + if (validate_move_rules(gamestate, &(candidates[i]))) {
1.105 + result = 1;
1.106 + if (threats && threatcount) {
1.107 + threats[(*threatcount)++] = candidates[i];
1.108 + }
1.109 + }
1.110 + }
1.111 +
1.112 + return result;
1.113 +}
1.114 +
1.115 +_Bool is_pinned(GameState *gamestate, Move *move) {
1.116 + uint8_t color = move->piece & COLOR_MASK;
1.117 +
1.118 + uint8_t kingfile = 0, kingrow = 0;
1.119 + for (uint8_t row = 0 ; row < 8 ; row++) {
1.120 + for (uint8_t file = 0 ; file < 8 ; file++) {
1.121 + if (gamestate->board[row][file] == (color|KING)) {
1.122 + kingfile = file;
1.123 + kingrow = row;
1.124 + }
1.125 + }
1.126 + }
1.127 +
1.128 + GameState simulation = *gamestate;
1.129 + Move simmove = *move;
1.130 + apply_move(&simulation, &simmove);
1.131 + return is_covered(&simulation, kingrow, kingfile, opponent_color(color));
1.132 +}
1.133 +
1.134 +_Bool get_real_threats(GameState *gamestate, uint8_t row, uint8_t file,
1.135 + uint8_t color, Move *threats, uint8_t *threatcount) {
1.136 +
1.137 + if (threatcount) {
1.138 + *threatcount = 0;
1.139 + }
1.140 +
1.141 + Move candidates[16];
1.142 + uint8_t candidatecount;
1.143 + if (get_threats(gamestate, row, file, color, candidates, &candidatecount)) {
1.144 +
1.145 + _Bool result = 0;
1.146 + uint8_t kingfile = 0, kingrow = 0;
1.147 + for (uint8_t row = 0 ; row < 8 ; row++) {
1.148 + for (uint8_t file = 0 ; file < 8 ; file++) {
1.149 + if (gamestate->board[row][file] == (color|KING)) {
1.150 + kingfile = file;
1.151 + kingrow = row;
1.152 + }
1.153 + }
1.154 + }
1.155 +
1.156 + for (uint8_t i = 0 ; i < candidatecount ; i++) {
1.157 + GameState simulation = *gamestate;
1.158 + Move simmove = candidates[i];
1.159 + apply_move(&simulation, &simmove);
1.160 + if (!is_covered(&simulation, kingrow, kingfile,
1.161 + opponent_color(color))) {
1.162 + result = 1;
1.163 + if (threats && threatcount) {
1.164 + threats[(*threatcount)++] = candidates[i];
1.165 + }
1.166 + }
1.167 + }
1.168 +
1.169 + return result;
1.170 + } else {
1.171 + return 0;
1.172 + }
1.173 +}
1.174 +#include <ncurses.h>
1.175 +static int getlocation(GameState *gamestate, Move *move) {
1.176 +
1.177 + uint8_t color = move->piece & COLOR_MASK;
1.178 + _Bool incheck = gamestate->lastmove?gamestate->lastmove->move.check:0;
1.179 +
1.180 + Move threats[16], *threat = NULL;
1.181 + uint8_t threatcount;
1.182 +
1.183 + if (get_threats(gamestate, move->torow, move->tofile, color,
1.184 + threats, &threatcount)) {
1.185 +
1.186 + // find threats for the specified position
1.187 + for (uint8_t i = 0 ; i < threatcount ; i++) {
1.188 + if ((threats[i].piece & (PIECE_MASK | COLOR_MASK))
1.189 + == move->piece &&
1.190 + (move->fromrow == POS_UNSPECIFIED ||
1.191 + move->fromrow == threats[i].fromrow) &&
1.192 + (move->fromfile == POS_UNSPECIFIED ||
1.193 + move->fromfile == threats[i].fromfile)) {
1.194 +
1.195 + if (threat) {
1.196 + return AMBIGUOUS_MOVE;
1.197 + } else {
1.198 + threat = &(threats[i]);
1.199 + }
1.200 + }
1.201 + }
1.202 +
1.203 + // can't threaten specified position
1.204 + if (!threat) {
1.205 + return INVALID_POSITION;
1.206 + }
1.207 +
1.208 + // found threat is no real threat
1.209 + if (is_pinned(gamestate, threat)) {
1.210 + return incheck?KING_IN_CHECK:PIECE_PINNED;
1.211 + } else {
1.212 + memcpy(move, threat, sizeof(Move));
1.213 + return VALID_MOVE_SYNTAX;
1.214 + }
1.215 + } else {
1.216 + return INVALID_POSITION;
1.217 + }
1.218 +}
1.219 +
1.220 int eval_move(GameState *gamestate, char *mstr, Move *move) {
1.221 memset(move, 0, sizeof(Move));
1.222 move->fromfile = POS_UNSPECIFIED;
1.223 @@ -452,83 +596,6 @@
1.224 }
1.225 }
1.226
1.227 -_Bool get_threats(GameState *gamestate, uint8_t row, uint8_t file,
1.228 - uint8_t color, Move *threats, uint8_t *threatcount) {
1.229 - Move candidates[16];
1.230 - int candidatecount = 0;
1.231 - for (uint8_t r = 0 ; r < 8 ; r++) {
1.232 - for (uint8_t f = 0 ; f < 8 ; f++) {
1.233 - if ((gamestate->board[r][f] & COLOR_MASK) == color) {
1.234 - memset(&(candidates[candidatecount]), 0, sizeof(Move));
1.235 - candidates[candidatecount].piece = gamestate->board[r][f];
1.236 - candidates[candidatecount].fromrow = r;
1.237 - candidates[candidatecount].fromfile = f;
1.238 - candidates[candidatecount].torow = row;
1.239 - candidates[candidatecount].tofile = file;
1.240 - candidatecount++;
1.241 - }
1.242 - }
1.243 - }
1.244 -
1.245 - if (threatcount) {
1.246 - *threatcount = 0;
1.247 - }
1.248 -
1.249 -
1.250 - _Bool result = 0;
1.251 -
1.252 - for (int i = 0 ; i < candidatecount ; i++) {
1.253 - if (validate_move_rules(gamestate, &(candidates[i]))) {
1.254 - result = 1;
1.255 - if (threats && threatcount) {
1.256 - threats[(*threatcount)++] = candidates[i];
1.257 - }
1.258 - }
1.259 - }
1.260 -
1.261 - return result;
1.262 -}
1.263 -
1.264 -_Bool get_real_threats(GameState *gamestate, uint8_t row, uint8_t file,
1.265 - uint8_t color, Move *threats, uint8_t *threatcount) {
1.266 -
1.267 - Move candidates[16];
1.268 - uint8_t candidatecount;
1.269 - if (get_threats(gamestate, row, file, color, candidates, &candidatecount)) {
1.270 -
1.271 - if (threatcount) {
1.272 - *threatcount = 0;
1.273 - }
1.274 - _Bool result = 0;
1.275 - uint8_t kingfile = 0, kingrow = 0;
1.276 - for (uint8_t row = 0 ; row < 8 ; row++) {
1.277 - for (uint8_t file = 0 ; file < 8 ; file++) {
1.278 - if ((gamestate->board[row][file] & COLOR_MASK) == color) {
1.279 - kingfile = file;
1.280 - kingrow = row;
1.281 - }
1.282 - }
1.283 - }
1.284 -
1.285 - for (uint8_t i = 0 ; i < candidatecount ; i++) {
1.286 - GameState simulation;
1.287 - memcpy(&simulation, gamestate, sizeof(GameState));
1.288 - apply_move(&simulation, &(candidates[i]));
1.289 - if (!is_covered(&simulation, kingrow, kingfile,
1.290 - opponent_color(color))) {
1.291 - result = 1;
1.292 - if (threats && threatcount) {
1.293 - threats[(*threatcount)++] = candidates[i];
1.294 - }
1.295 - }
1.296 - }
1.297 -
1.298 - return result;
1.299 - } else {
1.300 - return 0;
1.301 - }
1.302 -}
1.303 -
1.304 _Bool is_protected(GameState *gamestate, uint8_t row, uint8_t file,
1.305 uint8_t color) {
1.306
