static bool
opponent_has_positive_capture(const struct node *node)
{
const struct position *pos = node->pos;
uint64_t attacks = pos->attack[opponent_pawn];
uint64_t victims = pos->map[0] & ~pos->map[pawn];
if (is_nonempty(attacks & victims))
return true;
attacks |= pos->attack[opponent_knight];
attacks |= pos->attack[opponent_bishop];
victims &= ~pos->map[bishop];
victims &= ~pos->map[knight];
if (is_nonempty(attacks & victims))
return true;
attacks |= pos->attack[opponent_rook];
victims = pos->map[queen];
if (is_nonempty(attacks & victims))
return true;
attacks = pos->attack[opponent_king];
victims = pos->map[0] & ~pos->attack[0];
if (is_nonempty(attacks & victims))
return true;
return false;
}
static char*
print_san_move_from(const struct position *pos, move m,
char *str, enum player turn)
{
move moves[MOVE_ARRAY_LENGTH];
uint64_t ambig_pieces = UINT64_C(0);
enum piece p = pos_piece_at(pos, mfrom(m));
(void) gen_moves(pos, moves);
for (move *im = moves; *im != 0; ++im) {
if ((mfrom(*im) != mfrom(m)) && (mto(*im) == mto(m))
&& (pos_piece_at(pos, mfrom(*im)) == p))
ambig_pieces |= mfrom64(*im);
}
if ((p == pawn) && is_capture(m)) {
*(str++) = index_to_file_ch(mfrom(m));
}
else if (is_nonempty(ambig_pieces)) {
if (is_nonempty(ambig_pieces & file64(mfrom(m)))) {
if (is_nonempty(ambig_pieces & rank64(mfrom(m)))) {
*(str++) = index_to_file_ch(mfrom(m));
}
*(str++) = index_to_rank_ch(mfrom(m), turn);
}
else {
*(str++) = index_to_file_ch(mfrom(m));
}
}
return str;
}
