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));
}
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;
}
static bool san_to_lan(const char san[], const board_t * board, char string[], int size) {
int len;
int left, right;
int c;
int king, rook;
char king_string[3], rook_string[3];
ASSERT(san!=NULL);
ASSERT(board_is_ok(board));
ASSERT(string!=NULL);
ASSERT(size>=8);
// init
if (size < 8) return false;
strcpy(string,"???????");
len = strlen(san);
left = 0;
right = len;
// skip trailing '+' or '#'
if (left < right) {
c = san[right-1];
if (c == '+' || c == '#') right--;
}
// castling
ASSERT(left==0);
if (false) {
} else if (right == 3 && strncmp(san,"O-O",3) == 0) {
if (board->castle[board->turn][SideH] == SquareNone) return false;
king = king_pos(board,board->turn);
rook = board->castle[board->turn][SideH];
square_to_string(king,king_string,3);
square_to_string(rook,rook_string,3);
sprintf(string,"K%s?%s?",king_string,rook_string);
} else if (right == 5 && strncmp(san,"O-O-O",5) == 0) {
if (board->castle[board->turn][SideA] == SquareNone) return false;
king = king_pos(board,board->turn);
rook = board->castle[board->turn][SideA];
square_to_string(king,king_string,3);
square_to_string(rook,rook_string,3);
sprintf(string,"K%s?%s?",king_string,rook_string);
} else {
// moved piece
if (left < right) {
c = san[left];
if (char_is_piece(c)) {
string[0] = c;
left++;
}
}
// promotion
if (left < right) {
c = toupper(san[right-1]);
if (char_is_piece(c)) {
string[6] = c;
right--;
// skip '='
if (left < right && san[right-1] == '=') right--;
}
}
// to-square rank
if (left < right) {
c = san[right-1];
if (char_is_rank(c)) {
string[5] = c;
right--;
}
}
// to-square file
if (left < right) {
c = san[right-1];
if (char_is_file(c)) {
string[4] = c;
right--;
}
}
// captured piece
if (left < right) {
c = san[right-1];
if (char_is_piece(c)) {
string[3] = c;
right--;
}
}
// skip middle '-' or 'x'
if (left < right) {
c = san[right-1];
if (c == '-' || c == 'x') right--;
}
// from-square file
if (left < right) {
c = san[left];
if (char_is_file(c)) {
string[1] = c;
left++;
}
}
// from-square rank
if (left < right) {
c = san[left];
if (char_is_rank(c)) {
string[2] = c;
left++;
}
}
if (left != right) return false;
}
// end
return true;
}