Sat, 29 Mar 2014 14:46:33 +0100
implemented bishop rules
universe@10 | 1 | /* |
universe@10 | 2 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. |
universe@10 | 3 | * |
universe@10 | 4 | * Copyright 2014 Mike Becker. All rights reserved. |
universe@10 | 5 | * |
universe@10 | 6 | * Redistribution and use in source and binary forms, with or without |
universe@10 | 7 | * modification, are permitted provided that the following conditions are met: |
universe@10 | 8 | * |
universe@10 | 9 | * 1. Redistributions of source code must retain the above copyright |
universe@10 | 10 | * notice, this list of conditions and the following disclaimer. |
universe@10 | 11 | * |
universe@10 | 12 | * 2. Redistributions in binary form must reproduce the above copyright |
universe@10 | 13 | * notice, this list of conditions and the following disclaimer in the |
universe@10 | 14 | * documentation and/or other materials provided with the distribution. |
universe@10 | 15 | * |
universe@10 | 16 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
universe@10 | 17 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
universe@10 | 18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
universe@10 | 19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
universe@10 | 20 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
universe@10 | 21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
universe@10 | 22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
universe@10 | 23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
universe@10 | 24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
universe@10 | 25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
universe@10 | 26 | * POSSIBILITY OF SUCH DAMAGE. |
universe@10 | 27 | * |
universe@10 | 28 | */ |
universe@10 | 29 | |
universe@10 | 30 | #include "bishop.h" |
universe@16 | 31 | #include "rules.h" |
universe@17 | 32 | #include <math.h> |
universe@10 | 33 | |
universe@16 | 34 | _Bool bishop_chkrules(Move* move) { |
universe@17 | 35 | return abs(move->torow-move->fromrow) == abs(move->tofile-move->fromfile); |
universe@17 | 36 | } |
universe@17 | 37 | |
universe@17 | 38 | _Bool bishop_isblocked(Board board, Move *move) { |
universe@17 | 39 | int dy = move->torow > move->fromrow ? 1 : -1; |
universe@17 | 40 | int dx = move->tofile > move->fromfile ? 1 : -1; |
universe@17 | 41 | |
universe@17 | 42 | uint8_t y = move->fromrow; |
universe@17 | 43 | uint8_t x = move->fromfile; |
universe@17 | 44 | |
universe@17 | 45 | do { |
universe@17 | 46 | x += dx; |
universe@17 | 47 | y += dy; |
universe@17 | 48 | if (board[y][x]) { |
universe@17 | 49 | return TRUE; |
universe@17 | 50 | } |
universe@17 | 51 | } while (x != move->tofile && y != move->torow); |
universe@17 | 52 | |
universe@12 | 53 | return FALSE; |
universe@10 | 54 | } |
universe@10 | 55 | |
universe@17 | 56 | static int bishop_getloc_fixedfile(Board board, Move *move) { |
universe@17 | 57 | uint8_t d = abs(move->fromfile - move->tofile); |
universe@17 | 58 | if (board[move->torow - d][move->fromfile] == move->piece) { |
universe@17 | 59 | move->fromrow = move->torow - d; |
universe@17 | 60 | } |
universe@17 | 61 | if (board[move->torow + d][move->fromfile] == move->piece) { |
universe@17 | 62 | if (move->fromrow == POS_UNSPECIFIED) { |
universe@17 | 63 | move->fromrow = move->torow + d; |
universe@17 | 64 | } else { |
universe@17 | 65 | return AMBIGUOUS_MOVE; /* rare situation after promotion */ |
universe@17 | 66 | } |
universe@17 | 67 | } |
universe@17 | 68 | return move->fromrow == POS_UNSPECIFIED ? |
universe@17 | 69 | INVALID_POSITION : VALID_MOVE_SYNTAX; |
universe@17 | 70 | } |
universe@17 | 71 | |
universe@17 | 72 | static int bishop_getloc_fixedrow(Board board, Move *move) { |
universe@17 | 73 | uint8_t d = abs(move->fromrow - move->torow); |
universe@17 | 74 | if (board[move->fromrow][move->tofile - d] == move->piece) { |
universe@17 | 75 | move->fromfile = move->tofile - d; |
universe@17 | 76 | } |
universe@17 | 77 | if (board[move->fromrow][move->tofile + d] == move->piece) { |
universe@17 | 78 | if (move->fromfile == POS_UNSPECIFIED) { |
universe@17 | 79 | move->fromfile = move->tofile + d; |
universe@17 | 80 | } else { |
universe@17 | 81 | return AMBIGUOUS_MOVE; /* rare situation after promotion */ |
universe@17 | 82 | } |
universe@17 | 83 | } |
universe@17 | 84 | return move->fromfile == POS_UNSPECIFIED ? |
universe@17 | 85 | INVALID_POSITION : VALID_MOVE_SYNTAX; |
universe@10 | 86 | } |
universe@10 | 87 | |
universe@16 | 88 | int bishop_getlocation(Board board, Move *move) { |
universe@17 | 89 | |
universe@17 | 90 | if (move->fromfile != POS_UNSPECIFIED) { |
universe@17 | 91 | return bishop_getloc_fixedfile(board, move); |
universe@17 | 92 | } |
universe@17 | 93 | |
universe@17 | 94 | if (move->fromrow != POS_UNSPECIFIED) { |
universe@17 | 95 | return bishop_getloc_fixedrow(board, move); |
universe@17 | 96 | } |
universe@17 | 97 | |
universe@17 | 98 | _Bool amb = FALSE; |
universe@17 | 99 | for (int d = -7 ; d < 8 ; d++) { |
universe@17 | 100 | uint8_t row = move->torow + d; |
universe@17 | 101 | if (isidx(row)) { |
universe@17 | 102 | uint8_t file = move->tofile + d; |
universe@17 | 103 | if (isidx(file) && board[row][file] == move->piece) { |
universe@17 | 104 | if (amb) { |
universe@17 | 105 | return AMBIGUOUS_MOVE; |
universe@17 | 106 | } |
universe@17 | 107 | amb = TRUE; |
universe@17 | 108 | move->fromrow = row; |
universe@17 | 109 | move->fromfile = file; |
universe@17 | 110 | } |
universe@17 | 111 | file = move->tofile - d; |
universe@17 | 112 | if (isfile(file) && board[row][file] == move->piece) { |
universe@17 | 113 | if (amb) { |
universe@17 | 114 | return AMBIGUOUS_MOVE; |
universe@17 | 115 | } |
universe@17 | 116 | amb = TRUE; |
universe@17 | 117 | move->fromrow = row; |
universe@17 | 118 | move->fromfile = file; |
universe@17 | 119 | } |
universe@17 | 120 | } |
universe@17 | 121 | } |
universe@17 | 122 | |
universe@17 | 123 | if (move->fromrow == POS_UNSPECIFIED || move->fromfile == POS_UNSPECIFIED) { |
universe@17 | 124 | return INVALID_POSITION; |
universe@17 | 125 | } else { |
universe@17 | 126 | return VALID_MOVE_SYNTAX; |
universe@17 | 127 | } |
universe@10 | 128 | } |