Refactored isKingLeftInCheck() (#726)

chesslablab · Jan 27, 2025 · 8f61020 · 8f61020
1 parent fd95a1f
commit 8f61020
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Showing 2 changed files with 23 additions and 22 deletions.
diff --git a/src/Variant/AbstractPiece.php b/src/Variant/AbstractPiece.php
@@ -315,32 +315,23 @@ public function isPinned(): ?AbstractPiece
      */
     public function isKingLeftInCheck(): bool
     {
-        $isCheck = false;
-        $turn = $this->board->turn;
-        $history = $this->board->history;
-        $castlingAbility = $this->board->castlingAbility;
-        $sqCount = $this->board->sqCount;
-        $spaceEval = $this->board->spaceEval;
-        $pieces = $this->board->pieces();
-        if ($this->move()) {
-            $isCheck = $this->board->piece($this->color, Piece::K)?->attacking() != [];
-            $this->board->turn = $turn;
-            $this->board->history = $history;
-            $this->board->castlingAbility = $castlingAbility;
-            $this->board->sqCount = $sqCount;
-            $this->board->spaceEval = $spaceEval;
-            $this->board->rewind();
-            while ($this->board->valid()) {
-                $piece = $this->board->current();
-                $this->board->next();
-                $this->board->detach($piece);
+        if ($king = $this->board->piece($this->color, Piece::K)) {
+            foreach ($king->attacking() as $attacking) {
+                if ($this->move['to'] !== $attacking->sq && 
+                    !in_array($this->move['to'], $attacking->line($king->sq))
+                ) {
+                    return true;
+                }
             }
-            foreach ($pieces as $val) {
-                $this->board->attach($val);
+        }        
+        if ($pinning = $this->isPinned()) {
+            if ($this->move['to'] !== $pinning->sq && 
+                !in_array($this->move['to'], $pinning->line($king->sq))) {
+                return true;
             }
         }
 
-        return $isCheck;
+        return false;
     }
 
     /**

diff --git a/src/Variant/Classical/K.php b/src/Variant/Classical/K.php
@@ -184,4 +184,14 @@ public function castle(string $rookType): bool
 
         return false;
     }
+
+    /**
+     * Returns true if the king is left in check because of moving the piece.
+     *
+     * @return bool
+     */
+    public function isKingLeftInCheck(): bool
+    {
+        return in_array($this->move['to'], $this->board->spaceEval[$this->oppColor()]);
+    }
 }