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#define MOVES_INTERNAL
#include "engine/moves.h"
static bool pawn_attacks_square(position_t position, square_t square, u8 by_color) {
bitboard_t enemy_pawns;
if (by_color == WHITE_TURN) {
enemy_pawns = position.bitboards[WHITE_PAWN];
if (square < 8) return false;
bitboard_t nw = (square % 8 == 7) ? 0 : (enemy_pawns >> (square - 7));
bitboard_t ne = (square % 8 == 0) ? 0 : (enemy_pawns >> (square - 9));
return (nw | ne) & 1;
} else {
enemy_pawns = position.bitboards[BLACK_PAWN];
if (square > 54) return false;
bitboard_t se = (square % 8 == 0) ? 0 : (enemy_pawns >> (square + 7));
bitboard_t sw = (square % 8 == 7) ? 0 : (enemy_pawns >> (square + 9));
return (se | sw) & 1;
}
}
static bool knight_attacks_square(position_t position, square_t square, u8 by_color) {
bitboard_t enemy_knights = (by_color == WHITE_TURN)
? position.bitboards[WHITE_KNIGHT]
: position.bitboards[BLACK_KNIGHT];
return knight_moves[square] & enemy_knights;
}
static bool king_attacks_square(position_t position, square_t square, u8 by_color) {
bitboard_t enemy_king = (by_color == WHITE_TURN)
? position.bitboards[WHITE_KING]
: position.bitboards[BLACK_KING];
bitboard_t movement;
if (square >= 10) {
movement = 920078ULL << (square - 10);
} else {
movement = 920078ULL >> -(square - 10);
}
if ((bitboard_t)1 << square & BITMASK_FILE_A) {
movement &= BITMASK_FILE_A | BITMASK_FILE_B;
} else if ((bitboard_t)1 << square & BITMASK_FILE_H) {
movement &= BITMASK_FILE_G | BITMASK_FILE_H;
}
return movement & enemy_king;
}
static bool sliding_attacks_square(
position_t position,
square_t square,
u8 by_color,
bool check_rook,
bool check_bishop
) {
bitboard_t all_occupied = whites(position) | blacks(position);
if (check_rook) {
bitboard_t rook_like = (by_color == WHITE_TURN)
? (position.bitboards[WHITE_ROOK] | position.bitboards[WHITE_QUEEN])
: (position.bitboards[BLACK_ROOK] | position.bitboards[BLACK_QUEEN]);
if (get_rook_attacks(square, all_occupied) & rook_like) return true;
}
if (check_bishop) {
bitboard_t bishop_like = (by_color == WHITE_TURN)
? (position.bitboards[WHITE_BISHOP] | position.bitboards[WHITE_QUEEN])
: (position.bitboards[BLACK_BISHOP] | position.bitboards[BLACK_QUEEN]);
if (get_bishop_attacks(square, all_occupied) & bishop_like) return true;
}
return false;
}
bool square_attacked(position_t position, square_t square, u8 by_color) {
if (pawn_attacks_square(position, square, by_color)) return true;
if (knight_attacks_square(position, square, by_color)) return true;
if (king_attacks_square(position, square, by_color)) return true;
if (sliding_attacks_square(position, square, by_color, true, true)) return true;
return false;
}
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