+#include "bitboard.h"
+#include "position.h"
+#include "search.h"
+#include "thread.h"
+#include "tt.h"
+#include "uci.h"
+#include "syzygy/tbprobe.h"
+
+#include <grpc/grpc.h>
+#include <grpc++/server.h>
+#include <grpc++/server_builder.h>
+#include "hashprobe.grpc.pb.h"
+
+using grpc::Server;
+using grpc::ServerBuilder;
+using grpc::ServerContext;
+using grpc::Status;
+using grpc::StatusCode;
+using namespace hashprobe;
+
+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;
+ }
+ }
+
+ response->set_depth(entry->depth());
+ FillValue(eval, response->mutable_eval());
+ FillValue(value, response->mutable_value());
+ response->set_bound(HashProbeLine::ValueBound(bound));
+
+ // Follow the PV until we hit an illegal move.
+ std::stack<Move> pv;
+ std::set<Key> seen;
+ while (found && is_ok(entry->move())) {
+ FillMove(entry->move(), response->add_pv());
+ if (seen.count(pos->key())) break;
+ pv.push(entry->move());
+ seen.insert(pos->key());
+ setup_states->push(StateInfo());
+ pos->do_move(entry->move(), setup_states->top(), pos->gives_check(entry->move(), CheckInfo(*pos)));
+ entry = TT.probe(pos->key(), found);
+ }
+
+ // Unroll the PV back again, so the Position object remains unchanged.
+ while (!pv.empty()) {
+ pos->undo_move(pv.top());
+ pv.pop();
+ }
+ }
+ }
+
+ void FillValue(Value value, HashProbeScore* score) {
+ if (abs(value) < VALUE_MATE - MAX_PLY) {
+ score->set_score_type(HashProbeScore::SCORE_CP);
+ score->set_score_cp(value * 100 / PawnValueEg);
+ } else {
+ score->set_score_type(HashProbeScore::SCORE_MATE);
+ score->set_score_mate((value > 0 ? VALUE_MATE - value + 1 : -VALUE_MATE - value) / 2);
+ }
+ }
+};
+
+void rpc_thread()
+{
+ std::string server_address("0.0.0.0:50051");
+ HashProbeImpl service;
+
+ ServerBuilder builder;
+ builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());
+ builder.RegisterService(&service);
+ std::unique_ptr<Server> server(builder.BuildAndStart());
+ std::cout << "Server listening on " << server_address << std::endl;
+ server->Wait();
+}