+class HashProbeImpl final : public HashProbe::Service {
+public:
+ Status Probe(ServerContext* context,
+ const HashProbeRequest* request,
+ HashProbeResponse *response) {
+ Position pos(request->fen(), /*isChess960=*/false, Threads.main());
+ if (!pos.pos_is_ok()) {
+ return Status(StatusCode::INVALID_ARGUMENT, "Invalid FEN");
+ }
+
+ bool invert = (pos.side_to_move() == BLACK);
+ Search::StateStackPtr setup_states = Search::StateStackPtr(new std::stack<StateInfo>);
+
+ ProbeMove(&pos, setup_states.get(), invert, response->mutable_root());
+
+ MoveList<LEGAL> moves(pos);
+ for (const ExtMove* em = moves.begin(); em != moves.end(); ++em) {
+ HashProbeLine *line = response->add_line();
+ FillMove(em->move, line->mutable_move());
+ setup_states->push(StateInfo());
+ pos.do_move(em->move, setup_states->top(), pos.gives_check(em->move, CheckInfo(pos)));
+ ProbeMove(&pos, setup_states.get(), !invert, line);
+ pos.undo_move(em->move);
+ }
+
+ return Status::OK;
+ }
+
+ void FillMove(Move move, HashProbeMove* decoded) {
+ if (!is_ok(move)) return;
+
+ Square from = from_sq(move);
+ Square to = to_sq(move);
+
+ if (type_of(move) == CASTLING) {
+ to = make_square(to > from ? FILE_G : FILE_C, rank_of(from));
+ }
+
+ decoded->set_from_sq(UCI::square(from));
+ decoded->set_to_sq(UCI::square(to));
+
+ if (type_of(move) == PROMOTION) {
+ decoded->set_promotion(std::string() + " PNBRQK"[promotion_type(move)]);
+ }
+ }
+
+ void ProbeMove(Position* pos, std::stack<StateInfo>* setup_states, bool invert, HashProbeLine* response) {
+ bool found;
+ TTEntry *entry = TT.probe(pos->key(), found);
+ response->set_found(found);
+ if (found) {
+ Value value = entry->value();
+ Value eval = entry->eval();
+ Bound bound = entry->bound();
+
+ if (invert) {
+ value = -value;
+ eval = -eval;
+ if (bound == BOUND_UPPER) {
+ bound = BOUND_LOWER;
+ } else if (bound == BOUND_LOWER) {
+ bound = BOUND_UPPER;
+ }
+ }