bool is_pinned(const board_t * board, int from, int to, int colour) {
int king;
int inc;
int sq, piece;
ASSERT(board!=NULL);
ASSERT(square_is_ok(from));
ASSERT(square_is_ok(to));
ASSERT(colour_is_ok(colour));
king = king_pos(board,colour);
inc = DELTA_INC(king-from);
if (inc == IncNone) return false; // not a line
sq = from;
do sq += inc;
while (board->square[sq] == Empty);
if (sq != king) return false; // blocker
sq = from;
do sq -= inc;
while ((piece=board->square[sq]) == Empty);
return square_is_ok(sq)
&& (piece & DELTA_MASK(king-sq)) != 0
&& piece_colour(piece) == colour_opp(colour)
&& DELTA_INC(king-to) != inc;
}
bool is_in_check(const board_t * board, int colour) {
ASSERT(board_is_ok(board));
ASSERT(colour_is_ok(colour));
return is_attacked(board,king_pos(board,colour),colour_opp(colour));
}
int king_pos(const board_t * board, int colour) {
ASSERT(board_is_ok(board));
ASSERT(colour_is_ok(colour));
return board->list[colour][0];
}
bool is_attacked(const board_t * board, int to, int colour) {
const uint8 * ptr;
int from, piece;
ASSERT(board_is_ok(board));
ASSERT(square_is_ok(to));
ASSERT(colour_is_ok(colour));
for (ptr = board->list[colour]; (from=*ptr) != SquareNone; ptr++) {
piece = board->square[from];
ASSERT(colour_equal(piece,colour));
if (piece_attack(board,piece,from,to)) return true;
}
return false;
}
int colour_opp(int colour) {
ASSERT(colour_is_ok(colour));
return colour ^ (BlackFlag^WhiteFlag);
}
bool colour_equal(int colour_1, int colour_2) {
ASSERT(colour_is_ok(colour_2));
return (colour_1 & colour_2) != 0;
}
bool colour_is_black(int colour) {
ASSERT(colour_is_ok(colour));
return colour == Black;
}
bool colour_is_white(int colour) {
ASSERT(colour_is_ok(colour));
return colour == White;
}
bool board_is_ok(const board_t * board) {
int sq, piece;
int colour, pos;
int king, rook;
if (board == NULL) return false;
// optional heavy DEBUG mode
if (!UseSlowDebug) return true;
// squares
for (sq = 0; sq < SquareNb; sq++) {
piece = board->square[sq];
if (square_is_ok(sq)) {
pos = board->pos[sq];
if (piece == Empty) {
if (pos != -1) return false;
} else {
if (pos < 0) return false;
if (board->list[piece_colour(piece)][pos] != sq) return false;
}
} else {
if (piece != Knight64) return false;
}
}
// white piece list
colour = White;
pos = 0;
if (board->list_size[colour] <= 0 || board->list_size[colour] > 16) return false;
sq = board->list[colour][pos];
if (sq == SquareNone) return false;
if (board->pos[sq] != pos) return false;
piece = board->square[sq];
if (!colour_equal(piece,colour) || !piece_is_king(piece)) return false;
for (pos++; pos < board->list_size[colour]; pos++) {
sq = board->list[colour][pos];
if (sq == SquareNone) return false;
if (board->pos[sq] != pos) return false;
if (!colour_equal(board->square[sq],colour)) return false;
}
sq = board->list[colour][pos];
if (sq != SquareNone) return false;
// black piece list
colour = Black;
pos = 0;
if (board->list_size[colour] <= 0 || board->list_size[colour] > 16) return false;
sq = board->list[colour][pos];
if (sq == SquareNone) return false;
if (board->pos[sq] != pos) return false;
piece = board->square[sq];
if (!colour_equal(piece,colour) || !piece_is_king(piece)) return false;
for (pos++; pos < board->list_size[colour]; pos++) {
sq = board->list[colour][pos];
if (sq == SquareNone) return false;
if (board->pos[sq] != pos) return false;
if (!colour_equal(board->square[sq],colour)) return false;
}
sq = board->list[colour][pos];
if (sq != SquareNone) return false;
// TODO: material
if (board->number[WhiteKing12] != 1) return false;
if (board->number[BlackKing12] != 1) return false;
if (!colour_is_ok(board->turn)) return false;
// castling status
if (board->castle[White][SideH] != SquareNone) {
king = board->list[White][0];
if (king < A1 || king > H1) return false;
if (board->square[king] != WhiteKing256) return false;
rook = board->castle[White][SideH];
if (rook < A1 || rook > H1) return false;
if (board->square[rook] != WhiteRook256) return false;
if (rook <= king) return false;
}
if (board->castle[White][SideA] != SquareNone) {
king = board->list[White][0];
if (king < A1 || king > H1) return false;
if (board->square[king] != WhiteKing256) return false;
rook = board->castle[White][SideA];
if (rook < A1 || rook > H1) return false;
if (board->square[rook] != WhiteRook256) return false;
if (rook >= king) return false;
}
if (board->castle[Black][SideH] != SquareNone) {
king = board->list[Black][0];
if (king < A8 || king > H8) return false;
if (board->square[king] != BlackKing256) return false;
rook = board->castle[Black][SideH];
if (rook < A8 || rook > H8) return false;
if (board->square[rook] != BlackRook256) return false;
if (rook <= king) return false;
}
if (board->castle[Black][SideA] != SquareNone) {
king = board->list[Black][0];
if (king < A8 || king > H8) return false;
if (board->square[king] != BlackKing256) return false;
rook = board->castle[Black][SideA];
if (rook < A8 || rook > H8) return false;
if (board->square[rook] != BlackRook256) return false;
if (rook >= king) return false;
}
return true;
}
int piece_make_pawn(int colour) {
ASSERT(colour_is_ok(colour));
return MakePawn[colour];
}
