From ed487d1227c21a0a5341e53e69a6fedde58bc229 Mon Sep 17 00:00:00 2001
From: Jean Bovet <jean_bovet@mac.com>
Date: Tue, 4 May 2021 21:31:35 -0700
Subject: [PATCH] Fixed issue where a manual move was not replacing the
 variations

---
 BChessTests/PGNTests.cpp             |  2 +-
 Shared/Bridge/FEngine.mm             |  2 +-
 Shared/Bridge/FEngineInfo.mm         |  2 +-
 Shared/Engine/Engine/ChessEngine.hpp |  4 ++--
 Shared/Engine/Engine/ChessGame.cpp   | 35 +++++++++++++++++-----------
 Shared/Engine/Engine/ChessGame.hpp   |  2 +-
 Shared/Engine/Helpers/FPGN.cpp       |  4 ++--
 7 files changed, 30 insertions(+), 21 deletions(-)

diff --git a/BChessTests/PGNTests.cpp b/BChessTests/PGNTests.cpp
index 3a87092..d29a038 100644
--- a/BChessTests/PGNTests.cpp
+++ b/BChessTests/PGNTests.cpp
@@ -166,7 +166,7 @@ TEST_F(PGN, GameWithBlackPromotion) {
     ASSERT_TRUE(FPGN::setGame("1.e4 Nf6 2.Nc3 Nxe4 3.Nxe4 d5 4.Nc3 Qd6 5.Nf3 h5 6.d4 Qd8 7.Bb5+ c6 8.Ba4 b5 9.Bb3 a5 10.a4 b4 11.Na2 Bg4 12.Qd3 Bxf3 13.Qxf3 h4 14.h3 Qd6 15.Bf4 Qe6+ 16.Be3 Qd6 17.O-O g6 18.c4 bxc3 19.bxc3 Nd7 20.c4 dxc4 21.Bxc4 Qf6 22.Qg4 e5 23.Rfe1 Qg7 24.dxe5 Nc5 25.Bxc5 Bxc5 26.e6 Bd4 27.exf7+ Kf8 28.Qe6 Qf6 29.Rad1 Qxe6 30.Bxe6 c5 31.Bd5 Rb8 32.Nc1 Rh5 33.Bc4 Rf5 34.Re2 Rf4 35.Rde1 Bxf2+ 36.Rxf2 Rxc4 37.Nd3 Kg7 38.Re7 Kf8 39.Re6 Rxa4 40.Nxc5 Ra1+ 41.Kh2 Rd1 42.Ne4 Kg7 43.Ng5 Rf8 44.Rfe2 Rxf7 45.Nxf7 Kxf7 46.R6e4 Ra1 47.Rxh4 Kg8 48.Rf2 Kg7 49.Rhf4 a4 50.Rf7+ Kh6 51.R2f4 a3 52.Rg4 a2 53.Rf6 Rh1+ 54.Kxh1", game));
     
     auto move = createPromotion(squareForName("a2"), squareForName("a1"), BLACK, PAWN, QUEEN);
-    game.move(move);
+    game.move(move, false);
     
     auto pgn = FPGN::getGame(game);
     ASSERT_EQ(pgn, "1. e4 Nf6 2. Nc3 Nxe4 3. Nxe4 d5 4. Nc3 Qd6 5. Nf3 h5 6. d4 Qd8 7. Bb5+ c6 8. Ba4 b5 9. Bb3 a5 10. a4 b4 11. Na2 Bg4 12. Qd3 Bxf3 13. Qxf3 h4 14. h3 Qd6 15. Bf4 Qe6+ 16. Be3 Qd6 17. O-O g6 18. c4 bxc3 19. bxc3 Nd7 20. c4 dxc4 21. Bxc4 Qf6 22. Qg4 e5 23. Rfe1 Qg7 24. dxe5 Nc5 25. Bxc5 Bxc5 26. e6 Bd4 27. exf7+ Kf8 28. Qe6 Qf6 29. Rad1 Qxe6 30. Bxe6 c5 31. Bd5 Rb8 32. Nc1 Rh5 33. Bc4 Rf5 34. Re2 Rf4 35. Rde1 Bxf2+ 36. Rxf2 Rxc4 37. Nd3 Kg7 38. Re7 Kf8 39. Re6 Rxa4 40. Nxc5 Ra1+ 41. Kh2 Rd1 42. Ne4 Kg7 43. Ng5 Rf8 44. Rfe2 Rxf7 45. Nxf7 Kxf7 46. Re6e4 Ra1 47. Rxh4 Kg8 48. Rf2 Kg7 49. Rhf4 a4 50. Rf7+ Kh6 51. Rf2f4 a3 52. Rg4 a2 53. Rf6 Rh1+ 54. Kxh1 a1=Q+ *");
diff --git a/Shared/Bridge/FEngine.mm b/Shared/Bridge/FEngine.mm
index 519199b..a41c2fe 100644
--- a/Shared/Bridge/FEngine.mm
+++ b/Shared/Bridge/FEngine.mm
@@ -132,7 +132,7 @@ - (FEngineMove*)engineMoveFromMove:(Move)fmove {
 }
 
 - (void)move:(NSUInteger)move {
-    engine.move((Move)move);
+    engine.move((Move)move, true);
     [self fireUpdate:self.stateIndex];
 }
 
diff --git a/Shared/Bridge/FEngineInfo.mm b/Shared/Bridge/FEngineInfo.mm
index 45b671b..cb5e5e7 100644
--- a/Shared/Bridge/FEngineInfo.mm
+++ b/Shared/Bridge/FEngineInfo.mm
@@ -105,7 +105,7 @@ - (NSString*)bestLine:(BOOL)uci {
         lineGame.history = NEW_HISTORY; // TODO hack to avoid coping the history from self.game and got it overwritten here
         for (int index=0; index<self.info.line.count; index++) {
             Move move = self.info.line[index];
-            lineGame.move(move);
+            lineGame.move(move, false);
         }
 
         // Get the PGN representation of the best line only
diff --git a/Shared/Engine/Engine/ChessEngine.hpp b/Shared/Engine/Engine/ChessEngine.hpp
index b137ed2..dd36d4e 100644
--- a/Shared/Engine/Engine/ChessEngine.hpp
+++ b/Shared/Engine/Engine/ChessEngine.hpp
@@ -79,8 +79,8 @@ class ChessEngine {
         return game.movesAt(file, rank);
     }
     
-    void move(Move move) {
-        game.move(move);
+    void move(Move move, bool replace) {
+        game.move(move, replace);
     }
     
     void move(std::string from, std::string to) {
diff --git a/Shared/Engine/Engine/ChessGame.cpp b/Shared/Engine/Engine/ChessGame.cpp
index f663a40..389e8a4 100644
--- a/Shared/Engine/Engine/ChessGame.cpp
+++ b/Shared/Engine/Engine/ChessGame.cpp
@@ -60,27 +60,36 @@ std::vector<Move> ChessGame::allMoves() {
     return all;
 }
 
-void ChessGame::move(Move move) {
+// move: the move to perform
+// replace: true to replace any variations by this move only,
+//          false to add as a new variation if the move does not exist already
+void ChessGame::move(Move move, bool replace) {
     assert(MOVE_ISVALID(move));
     
     // Lookup the node representing the last move by `moveIndexes`
-    root.lookupNode(0, moveIndexes.moveCursor, moveIndexes, [&move, this](auto & node) {
-        // First try to match the move with an existing move for that node.
-        // This happens, for example, when a PGN has been loaded and
-        // the player is playing a series of move that correspond to that PGN.
+    root.lookupNode(0, moveIndexes.moveCursor, moveIndexes, [&move, replace, this](auto & node) {
         bool found = false;
-        for (int index=0; index<node.variations.size(); index++) {
-            if (node.variations[index].move == move) {
-                moveIndexes.moves.push_back(index);
-                moveIndexes.moveCursor++;
-                found = true;
-                break;
+        if (replace) {
+            // Clear all the variations so this move
+            // becomes the only one available.
+            node.variations.clear();
+        } else {
+            // First try to match the move with an existing move for that node.
+            // This happens, for example, when a PGN has been loaded and
+            // the player is playing a series of move that correspond to that PGN.
+            for (int index=0; index<node.variations.size(); index++) {
+                if (node.variations[index].move == move) {
+                    moveIndexes.moves.push_back(index);
+                    moveIndexes.moveCursor++;
+                    found = true;
+                    break;
+                }
             }
         }
         
         // If the move is not found in any variations of this node, this mean
         // this is a new variation (either main variation if no variation exists yet).
-        if (!found) {
+        if (!found || replace) {
             MoveNode newNode = MoveNode();
             newNode.move = move;
             node.variations.push_back(newNode);
@@ -115,7 +124,7 @@ void ChessGame::move(Move move) {
 void ChessGame::move(std::string from, std::string to) {
     auto move = board.getMove(from, to);
     if (MOVE_ISVALID(move)) {
-        ChessGame::move(move);
+        ChessGame::move(move, false);
     }
 }
 
diff --git a/Shared/Engine/Engine/ChessGame.hpp b/Shared/Engine/Engine/ChessGame.hpp
index 0538274..9016c7e 100644
--- a/Shared/Engine/Engine/ChessGame.hpp
+++ b/Shared/Engine/Engine/ChessGame.hpp
@@ -135,7 +135,7 @@ class ChessGame {
     std::vector<Move> movesAt(File file, Rank rank);
     std::vector<Move> allMoves();
 
-    void move(Move move);
+    void move(Move move, bool replace);
     void move(std::string from, std::string to);
     
     bool canUndoMove();
diff --git a/Shared/Engine/Helpers/FPGN.cpp b/Shared/Engine/Helpers/FPGN.cpp
index feaeeb2..c7fe468 100644
--- a/Shared/Engine/Helpers/FPGN.cpp
+++ b/Shared/Engine/Helpers/FPGN.cpp
@@ -557,7 +557,7 @@ bool FPGN::parseMoveText(std::string pgn, unsigned &cursor, ChessGame &game, boo
         return false;
     }
 
-    game.move(whiteMove);
+    game.move(whiteMove, false);
 
 //    std::cout << to_string(whiteMove, SANType::full) << std::endl;
 //    game.board.print();
@@ -609,7 +609,7 @@ bool FPGN::parseMoveText(std::string pgn, unsigned &cursor, ChessGame &game, boo
     
     //    std::cout << MOVE_DESCRIPTION(blackMove) << std::endl;
     //    game.board.print();
-    game.move(blackMove);
+    game.move(blackMove, false);
 
     parseComment(pgn, cursor);