From b2bdcf657d06bb6bd50d5edd1f23a47706aca3ce Mon Sep 17 00:00:00 2001
From: Valery Gourov <va1ery@yandex.ru>
Date: Thu, 3 Sep 2026 12:14:47 +0300
Subject: [PATCH] MoveEval.bs update

---
 MoveEval.bs | 47 ++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 38 insertions(+), 9 deletions(-)

diff --git a/MoveEval.bs b/MoveEval.bs
index b80d873..b93520c 100644
--- a/MoveEval.bs
+++ b/MoveEval.bs
@@ -214,7 +214,7 @@ mkMoveEval = module
          in mkMoveRule "pawn_enpassant_left" (evalPieceIs Pawn && evalPos.rank == enPassantRank && otherHist.pawnMoved2 == Just movePos.file && evalPos.file > 0 && capturable capturePos) $ EnPassant {from=evalPos; to=movePos;})
         (let capturePos = Position {rank=evalPos.rank; file=evalPos.file + 1}
              movePos = Position {rank=evalPos.rank `pawnDirection` 1; file=evalPos.file + 1}
-         in mkMoveRule "pawn_enpassant_right" (evalPieceIs Pawn && evalPos.rank == enPassantRank && otherHist.pawnMoved2 == Just movePos.file && evalPos.file > 0 && capturable capturePos) $ EnPassant {from=evalPos; to=movePos;})
+         in mkMoveRule "pawn_enpassant_right" (evalPieceIs Pawn && evalPos.rank == enPassantRank && otherHist.pawnMoved2 == Just movePos.file && evalPos.file < 7 && capturable capturePos) $ EnPassant {from=evalPos; to=movePos;})
         `append` map (\ d ->
            let pos = dispPos evalPos d
            in mkMoveRule "king_move" (evalPieceIs King && dispInBounds evalPos d && (open pos || capturable pos)) $ Move {from=evalPos; to=pos;}) kingMoves
@@ -236,16 +236,45 @@ mkMoveEval = module
              in mkMoveRule "diagonal_move" cond $ Move {from=evalPos; to=pos;})
            (genVector :: Vector 7 Integer)) diagonalDisps)
         `append` vec
-        (let kingPath = vec kingStartPos (Position {rank=homeRank; file=3;}) (Position {rank=homeRank; file=2;})
-             between = vec (Position {rank=homeRank; file=1;}) (Position {rank=homeRank; file=2;}) (Position {rank=homeRank; file=3;})
-             threat = any (isThreatened state.board state.turn) kingPath
+        (let rookPos = Position {rank=homeRank; file=0;}
+             rookPresent = selectPos board rookPos == Just (Piece {color=turn; kind=Rook;})
+             kingPath = vec kingStartPos
+                            (Position {rank=homeRank; file=3;})
+                            (Position {rank=homeRank; file=2;})
+             between = vec (Position {rank=homeRank; file=1;})
+                           (Position {rank=homeRank; file=2;})
+                           (Position {rank=homeRank; file=3;})
+             threatBoard = updatePos board kingStartPos Nothing
+             threat = any (isThreatened threatBoard turn) kingPath
              clear = all open between
-         in mkMoveRule "castle_queenside" (evalPos == kingStartPos && not hist.kingMoved && not hist.qRookMoved && not threat && clear) $ Castle {kingSide=False})
-        (let kingPath = vec kingStartPos (Position {rank=homeRank; file=5;}) (Position {rank=homeRank; file=6;})
-             between = vec (Position {rank=homeRank; file=5;}) (Position {rank=homeRank; file=6;})
-             threat = any (isThreatened state.board state.turn) kingPath
+         in mkMoveRule "castle_queenside"
+              (evalPieceIs King &&
+               evalPos == kingStartPos &&
+               not hist.kingMoved &&
+               not hist.qRookMoved &&
+               rookPresent &&
+               not threat &&
+               clear)
+              $ Castle {kingSide=False})
+        (let rookPos = Position {rank=homeRank; file=7;}
+             rookPresent = selectPos board rookPos == Just (Piece {color=turn; kind=Rook;})
+             kingPath = vec kingStartPos
+                            (Position {rank=homeRank; file=5;})
+                            (Position {rank=homeRank; file=6;})
+             between = vec (Position {rank=homeRank; file=5;})
+                           (Position {rank=homeRank; file=6;})
+             threatBoard = updatePos board kingStartPos Nothing
+             threat = any (isThreatened threatBoard turn) kingPath
              clear = all open between
-         in mkMoveRule "castle_kingside" (evalPos == kingStartPos && not hist.kingMoved && not hist.kRookMoved && not threat && clear) $ Castle {kingSide=True})
+         in mkMoveRule "castle_kingside"
+              (evalPieceIs King &&
+               evalPos == kingStartPos &&
+               not hist.kingMoved &&
+               not hist.kRookMoved &&
+               rookPresent &&
+               not threat &&
+               clear)
+              $ Castle {kingSide=True})
 
   moveEval <- liftM (foldr1 joinMoveRule) $ sequence moveRules