1.1 --- a/src/chess/rules.c Wed May 28 15:47:57 2014 +0200
1.2 +++ b/src/chess/rules.c Wed Jun 11 15:38:01 2014 +0200
1.3 @@ -33,6 +33,17 @@
1.4 #include <stdlib.h>
1.5 #include <sys/time.h>
1.6
1.7 +static GameState gamestate_copy_sim(GameState *gamestate) {
1.8 + GameState simulation = *gamestate;
1.9 + if (simulation.lastmove) {
1.10 + MoveList *lastmovecopy = malloc(sizeof(MoveList));
1.11 + *lastmovecopy = *(simulation.lastmove);
1.12 + simulation.movelist = simulation.lastmove = lastmovecopy;
1.13 + }
1.14 +
1.15 + return simulation;
1.16 +}
1.17 +
1.18 void gamestate_cleanup(GameState *gamestate) {
1.19 MoveList *elem;
1.20 elem = gamestate->movelist;
1.21 @@ -145,67 +156,75 @@
1.22 addmove(gamestate, move);
1.23 }
1.24
1.25 -static _Bool validate_move_rules(GameState *gamestate, Move *move) {
1.26 +static int validate_move_rules(GameState *gamestate, Move *move) {
1.27 /* validate indices (don't trust opponent) */
1.28 if (!chkidx(move)) {
1.29 - return 0;
1.30 + return INVALID_POSITION;
1.31 }
1.32
1.33 /* must move */
1.34 if (move->fromfile == move->tofile && move->fromrow == move->torow) {
1.35 - return 0;
1.36 + return INVALID_MOVE_SYNTAX;
1.37 }
1.38
1.39 /* does piece exist */
1.40 if ((msrc(gamestate->board, move)&(PIECE_MASK|COLOR_MASK))
1.41 != (move->piece&(PIECE_MASK|COLOR_MASK))) {
1.42 - return 0;
1.43 + return INVALID_POSITION;
1.44 }
1.45
1.46 /* can't capture own pieces */
1.47 if ((mdst(gamestate->board, move) & COLOR_MASK)
1.48 == (move->piece & COLOR_MASK)) {
1.49 - return 0;
1.50 + return RULES_VIOLATED;
1.51 }
1.52
1.53 /* must capture, if and only if destination is occupied */
1.54 if ((mdst(gamestate->board, move) == 0 && move->capture) ||
1.55 (mdst(gamestate->board, move) != 0 && !move->capture)) {
1.56 - return 0;
1.57 + return INVALID_MOVE_SYNTAX;
1.58 }
1.59
1.60 /* validate individual rules */
1.61 + _Bool chkrules;
1.62 switch (move->piece & PIECE_MASK) {
1.63 case PAWN:
1.64 - return pawn_chkrules(gamestate, move) &&
1.65 + chkrules = pawn_chkrules(gamestate, move) &&
1.66 !pawn_isblocked(gamestate, move);
1.67 + break;
1.68 case ROOK:
1.69 - return rook_chkrules(move) &&
1.70 + chkrules = rook_chkrules(move) &&
1.71 !rook_isblocked(gamestate, move);
1.72 + break;
1.73 case KNIGHT:
1.74 - return knight_chkrules(move); /* knight is never blocked */
1.75 + chkrules = knight_chkrules(move); /* knight is never blocked */
1.76 + break;
1.77 case BISHOP:
1.78 - return bishop_chkrules(move) &&
1.79 + chkrules = bishop_chkrules(move) &&
1.80 !bishop_isblocked(gamestate, move);
1.81 + break;
1.82 case QUEEN:
1.83 - return queen_chkrules(move) &&
1.84 + chkrules = queen_chkrules(move) &&
1.85 !queen_isblocked(gamestate, move);
1.86 + break;
1.87 case KING:
1.88 - return king_chkrules(gamestate, move) &&
1.89 + chkrules = king_chkrules(gamestate, move) &&
1.90 !king_isblocked(gamestate, move);
1.91 + break;
1.92 default:
1.93 - return 0;
1.94 + return INVALID_MOVE_SYNTAX;
1.95 }
1.96 +
1.97 + return chkrules ? VALID_MOVE_SEMANTICS : RULES_VIOLATED;
1.98 }
1.99
1.100 -_Bool validate_move(GameState *gamestate, Move *move) {
1.101 - // TODO: provide more details via a return code
1.102 +int validate_move(GameState *gamestate, Move *move) {
1.103
1.104 - _Bool result = validate_move_rules(gamestate, move);
1.105 + int result = validate_move_rules(gamestate, move);
1.106
1.107 /* cancel processing to save resources */
1.108 - if (!result) {
1.109 - return 0;
1.110 + if (result != VALID_MOVE_SEMANTICS) {
1.111 + return result;
1.112 }
1.113
1.114 /* find kings for check validation */
1.115 @@ -226,15 +245,23 @@
1.116 }
1.117 }
1.118
1.119 - /* simulation move for check validation */
1.120 - GameState simulation = *gamestate;
1.121 + /* simulate move for check validation */
1.122 + GameState simulation = gamestate_copy_sim(gamestate);
1.123 Move simmove = *move;
1.124 apply_move(&simulation, &simmove);
1.125
1.126 /* don't move into or stay in check position */
1.127 if (is_covered(&simulation, mykingrow, mykingfile,
1.128 opponent_color(piececolor))) {
1.129 - return 0;
1.130 +
1.131 + gamestate_cleanup(&simulation);
1.132 + if ((move->piece & PIECE_MASK) == KING) {
1.133 + return KING_MOVES_INTO_CHECK;
1.134 + } else {
1.135 + /* last move is always not null in this case */
1.136 + return gamestate->lastmove->move.check ?
1.137 + KING_IN_CHECK : PIECE_PINNED;
1.138 + }
1.139 }
1.140
1.141 /* correct check and checkmate flags (move is still valid) */
1.142 @@ -315,7 +342,9 @@
1.143 }
1.144 }
1.145
1.146 - return 1;
1.147 + gamestate_cleanup(&simulation);
1.148 +
1.149 + return VALID_MOVE_SEMANTICS;
1.150 }
1.151
1.152 _Bool get_threats(GameState *gamestate, uint8_t row, uint8_t file,
1.153 @@ -351,7 +380,8 @@
1.154 _Bool result = 0;
1.155
1.156 for (int i = 0 ; i < candidatecount ; i++) {
1.157 - if (validate_move_rules(gamestate, &(candidates[i]))) {
1.158 + if (validate_move_rules(gamestate, &(candidates[i]))
1.159 + == VALID_MOVE_SEMANTICS) {
1.160 result = 1;
1.161 if (threats && threatcount) {
1.162 threats[(*threatcount)++] = candidates[i];
1.163 @@ -375,10 +405,14 @@
1.164 }
1.165 }
1.166
1.167 - GameState simulation = *gamestate;
1.168 + GameState simulation = gamestate_copy_sim(gamestate);
1.169 Move simmove = *move;
1.170 apply_move(&simulation, &simmove);
1.171 - return is_covered(&simulation, kingrow, kingfile, opponent_color(color));
1.172 + _Bool covered = is_covered(&simulation,
1.173 + kingrow, kingfile, opponent_color(color));
1.174 + gamestate_cleanup(&simulation);
1.175 +
1.176 + return covered;
1.177 }
1.178
1.179 _Bool get_real_threats(GameState *gamestate, uint8_t row, uint8_t file,
1.180 @@ -404,7 +438,7 @@
1.181 }
1.182
1.183 for (uint8_t i = 0 ; i < candidatecount ; i++) {
1.184 - GameState simulation = *gamestate;
1.185 + GameState simulation = gamestate_copy_sim(gamestate);
1.186 Move simmove = candidates[i];
1.187 apply_move(&simulation, &simmove);
1.188 if (!is_covered(&simulation, kingrow, kingfile,
1.189 @@ -414,6 +448,7 @@
1.190 threats[(*threatcount)++] = candidates[i];
1.191 }
1.192 }
1.193 + gamestate_cleanup(&simulation);
1.194 }
1.195
1.196 return result;
1.197 @@ -421,7 +456,7 @@
1.198 return 0;
1.199 }
1.200 }
1.201 -#include <ncurses.h>
1.202 +
1.203 static int getlocation(GameState *gamestate, Move *move) {
1.204
1.205 uint8_t color = move->piece & COLOR_MASK;
1.206 @@ -473,6 +508,9 @@
1.207 move->fromrow = POS_UNSPECIFIED;
1.208
1.209 size_t len = strlen(mstr);
1.210 + if (len < 1 || len > 6) {
1.211 + return INVALID_MOVE_SYNTAX;
1.212 + }
1.213
1.214 /* evaluate check/checkmate flags */
1.215 if (mstr[len-1] == '+') {
1.216 @@ -513,7 +551,6 @@
1.217 move->tofile = fileidx(mstr[1]);
1.218 move->torow = rowidx(mstr[2]);
1.219 }
1.220 -
1.221 } else if (len == 4) {
1.222 move->piece = getpiece(mstr[0]);
1.223 if (!move->piece) {
