From 9528fb98497d915ab166f02e8500b0da27462e10 Mon Sep 17 00:00:00 2001
From: Mattia Giambirtone <nocturn9x@nocturn9x.space>
Date: Sat, 20 Apr 2024 13:33:42 +0200
Subject: [PATCH] Fix crashes

---
 Chess/nimfish/nimfish.nim | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/Chess/nimfish/nimfish.nim b/Chess/nimfish/nimfish.nim
index 7ad1d72..a597d57 100644
--- a/Chess/nimfish/nimfish.nim
+++ b/Chess/nimfish/nimfish.nim
@@ -447,7 +447,7 @@ proc getAttacksTo*(self: ChessBoard, square: Square, attacker: PieceColor): Bitb
     result = result or self.getSlidingAttacks(square, attacker)
 
 
-proc updateCheckers(self: ChessBoard) =
+proc updateChecksAndPins(self: ChessBoard) =
     let 
         side = self.getSideToMove()
         king = self.getBitboard(King, side).toSquare()
@@ -491,7 +491,7 @@ proc generatePawnCaptures(self: ChessBoard, moves: var MoveList) =
         nonSideToMove = sideToMove.opposite()
         pawns = self.getBitboard(Pawn, sideToMove)
         # We can only capture enemy pieces (except the king)
-        enemyPieces = self.getOccupancyFor(nonSideToMove)
+        enemyPieces = self.getOccupancyFor(nonSideToMove) and not self.getBitboard(King, nonSideToMove)
         enemyPawns = self.getBitboard(Pawn, nonSideToMove)
         rightMovement = pawns.forwardRightRelativeTo(sideToMove)
         leftMovement = pawns.forwardLeftRelativeTo(sideToMove)
@@ -538,7 +538,8 @@ proc generateRookMoves(self: ChessBoard, moves: var MoveList) =
     let 
         sideToMove = self.getSideToMove()
         occupancy = self.getOccupancy()
-        enemyPieces = self.getOccupancyFor(sideToMove.opposite())
+        nonSideToMove = sideToMove.opposite()
+        enemyPieces = self.getOccupancyFor(sideToMove.opposite()) and not self.getBitboard(King, nonSideToMove)
         rooks = self.getBitboard(Rook, sideToMove) or self.getBitboard(Queen, sideToMove)
     for square in rooks:
         let 
@@ -555,7 +556,8 @@ proc generateBishopMoves(self: ChessBoard, moves: var MoveList) =
     ## Helper of generateSlidingMoves to generate bishop moves
     let 
         sideToMove = self.getSideToMove()
-        enemyPieces = self.getOccupancyFor(sideToMove.opposite())
+        nonSideToMove = sideToMove.opposite()
+        enemyPieces = self.getOccupancyFor(sideToMove.opposite()) and not self.getBitboard(King, nonSideToMove)
         occupancy = self.getOccupancy()
         bishops = self.getBitboard(Bishop, sideToMove) or self.getBitboard(Queen, sideToMove)
     for square in bishops:
@@ -584,7 +586,7 @@ proc generateKingMoves(self: ChessBoard, moves: var MoveList) =
         moveIdx = king.toSquare().uint64
         occupancy = self.getOccupancy()
         nonSideToMove = sideToMove.opposite()
-        enemyPieces = self.getOccupancyFor(nonSideToMove)
+        enemyPieces = self.getOccupancyFor(nonSideToMove) and not self.getBitboard(King, nonSideToMove)
     # Regular moves
     for square in KING_BITBOARDS[moveIdx] and not occupancy:
         moves.add(createMove(king, square))
@@ -600,7 +602,7 @@ proc generateKnightMoves(self: ChessBoard, moves: var MoveList)=
         knights = self.getBitboard(Knight, sideToMove)
         occupancy = self.getOccupancy()
         nonSideToMove = sideToMove.opposite()
-        enemyPieces = self.getOccupancyFor(nonSideToMove)
+        enemyPieces = self.getOccupancyFor(nonSideToMove) and not self.getBitboard(King, nonSideToMove)
     for square in knights:
         # Regular moves
         for target in KNIGHT_BITBOARDS[square.uint64] and not occupancy:
@@ -622,7 +624,6 @@ proc generateMoves*(self: ChessBoard, moves: var MoveList) =
     self.generatePawnMoves(moves)
     self.generateKnightMoves(moves)
     self.generateSlidingMoves(moves)
-    # self.updateCheckers()
 
 
 proc removePieceFromBitboard(self: ChessBoard, square: Square) =
@@ -734,6 +735,7 @@ proc doMove*(self: ChessBoard, move: Move) =
             else:
                 # Unreachable
                 discard
+    self.updateChecksAndPins()
 
 
 proc spawnPiece(self: ChessBoard, square: Square, piece: Piece) =