Mercurial > hg > terminal-chess / file comparison
comparison: src/chess/bishop.c
src/chess/bishop.c
- changeset 47
- d726e4b46c33
- parent 23
- 824c9522ce66
- child 55
- 54ea19938d57
equal
deleted
inserted
replaced
| 46:4dcfb4c58b6d | 47:d726e4b46c33 |
|---|---|
| 50 } | 50 } |
| 51 } | 51 } |
| 52 | 52 |
| 53 return 0; | 53 return 0; |
| 54 } | 54 } |
| 55 | |
| 56 static int bishop_getloc_fixedfile(GameState *gamestate, Move *move) { | |
| 57 uint8_t d = abs(move->fromfile - move->tofile); | |
| 58 if (gamestate->board[move->torow - d][move->fromfile] == move->piece) { | |
| 59 move->fromrow = move->torow - d; | |
| 60 } | |
| 61 if (gamestate->board[move->torow + d][move->fromfile] == move->piece) { | |
| 62 if (move->fromrow == POS_UNSPECIFIED) { | |
| 63 move->fromrow = move->torow + d; | |
| 64 } else { | |
| 65 return AMBIGUOUS_MOVE; /* rare situation after promotion */ | |
| 66 } | |
| 67 } | |
| 68 return move->fromrow == POS_UNSPECIFIED ? | |
| 69 INVALID_POSITION : VALID_MOVE_SYNTAX; | |
| 70 } | |
| 71 | |
| 72 static int bishop_getloc_fixedrow(GameState *gamestate, Move *move) { | |
| 73 uint8_t d = abs(move->fromrow - move->torow); | |
| 74 if (gamestate->board[move->fromrow][move->tofile - d] == move->piece) { | |
| 75 move->fromfile = move->tofile - d; | |
| 76 } | |
| 77 if (gamestate->board[move->fromrow][move->tofile + d] == move->piece) { | |
| 78 if (move->fromfile == POS_UNSPECIFIED) { | |
| 79 move->fromfile = move->tofile + d; | |
| 80 } else { | |
| 81 return AMBIGUOUS_MOVE; /* rare situation after promotion */ | |
| 82 } | |
| 83 } | |
| 84 return move->fromfile == POS_UNSPECIFIED ? | |
| 85 INVALID_POSITION : VALID_MOVE_SYNTAX; | |
| 86 } | |
| 87 | |
| 88 int bishop_getlocation(GameState *gamestate, Move *move) { | |
| 89 | |
| 90 if (move->fromfile != POS_UNSPECIFIED) { | |
| 91 return bishop_getloc_fixedfile(gamestate, move); | |
| 92 } | |
| 93 | |
| 94 if (move->fromrow != POS_UNSPECIFIED) { | |
| 95 return bishop_getloc_fixedrow(gamestate, move); | |
| 96 } | |
| 97 | |
| 98 _Bool amb = 0; | |
| 99 for (int d = -7 ; d < 8 ; d++) { | |
| 100 uint8_t row = move->torow + d; | |
| 101 if (isidx(row)) { | |
| 102 uint8_t file = move->tofile + d; | |
| 103 if (isidx(file) && gamestate->board[row][file] == move->piece) { | |
| 104 if (amb) { | |
| 105 return AMBIGUOUS_MOVE; | |
| 106 } | |
| 107 amb = 1; | |
| 108 move->fromrow = row; | |
| 109 move->fromfile = file; | |
| 110 } | |
| 111 file = move->tofile - d; | |
| 112 if (isidx(file) && gamestate->board[row][file] == move->piece) { | |
| 113 if (amb) { | |
| 114 return AMBIGUOUS_MOVE; | |
| 115 } | |
| 116 amb = 1; | |
| 117 move->fromrow = row; | |
| 118 move->fromfile = file; | |
| 119 } | |
| 120 } | |
| 121 } | |
| 122 | |
| 123 if (move->fromrow == POS_UNSPECIFIED || move->fromfile == POS_UNSPECIFIED) { | |
| 124 return INVALID_POSITION; | |
| 125 } else { | |
| 126 return VALID_MOVE_SYNTAX; | |
| 127 } | |
| 128 } |
