fix: remove unreachable dead code in BlokusGame.valid_move (game.py:220-260)

src/blokus_gym.egg-info/SOURCES.txt

@@ -16,4 +16,9 @@ src/blokus_gym/envs/multiagent.py
 src/blokus_gym/utils/__init__.py
 src/blokus_gym/utils/render.py
 src/blokus_gym/wrappers/__init__.py
-src/blokus_gym/wrappers/action_mask.py
+src/blokus_gym/wrappers/action_mask.py
+tests/test_board.py
+tests/test_envs.py
+tests/test_game.py
+tests/test_imports.py
+tests/test_pieces.py

src/blokus_gym/core/game.py

@@ -55,6 +55,14 @@ class BlokusGame:
         self._move_to_action: dict[tuple[int, int, int, int], int] = {}
         self._generate_action_space()
 
+        # Pre-compute action indices per piece for faster filtering
+        self._actions_by_piece: list[list[int]] = []
+        for piece_id in range(self.piece_set.num_pieces):
+            self._actions_by_piece.append([
+                idx for idx, move in enumerate(self._action_moves)
+                if move.piece_id == piece_id
+            ])
+
         # Starting corners for each player (standard Blokus layout)
         # 4 players: all four corners
         # 2 players: opposite corners (0,0) and (max, max)
@@ -197,7 +205,6 @@ class BlokusGame:
 
         # Rule 4: Corner rule (must touch same-color at a corner)
         if player.has_started:
-            # Must touch at least one same-color piece at a corner
             placed_corners = self._get_placed_corners(move)
             touches_corner = False
             for cx, cy in placed_corners:
@@ -207,7 +214,6 @@ class BlokusGame:
                         break
             if not touches_corner:
                 return False
-        # If not started yet, first move doesn't need to touch (it's the first piece)
 
         return True
 
@@ -219,12 +225,61 @@ class BlokusGame:
         if not player.can_move:
             return mask
 
-        for action_idx in range(self.num_actions):
-            move = self._action_moves[action_idx]
-            piece = self.piece_set.get_piece(move.piece_id)
-            if piece.name not in player.available_pieces:
-                continue
-            if self.valid_move(player_idx, move):
+        available_piece_ids = [
+            self.piece_set.get_piece_id(name)
+            for name in player.available_pieces
+        ]
+
+        if not player.has_started or not player.corners:
+            for piece_id in available_piece_ids:
+                for action_idx in self._actions_by_piece[piece_id]:
+                    if self.valid_move(player_idx, self._action_moves[action_idx]):
+                        mask[action_idx] = True
+            return mask
+
+        player_board_idx = player_idx + self.PLAYER_OFFSET
+
+        for piece_id in available_piece_ids:
+            for action_idx in self._actions_by_piece[piece_id]:
+                move = self._action_moves[action_idx]
+                placed_corners = self._get_placed_corners(move)
+
+                touches_corner = False
+                for cx, cy in placed_corners:
+                    if self.board.in_bounds(cx, cy):
+                        if self.board.get_cell(cx, cy) == player_board_idx:
+                            touches_corner = True
+                            break
+                if not touches_corner:
+                    continue
+
+                placed_squares = self._get_placed_squares(move)
+
+                valid = True
+                for x, y in placed_squares:
+                    if not self.board.in_bounds(x, y):
+                        valid = False
+                        break
+                if not valid:
+                    continue
+
+                if self.board.has_overlap(placed_squares):
+                    continue
+
+                for x, y in placed_squares:
+                    edge_invalid = False
+                    for dx, dy in [(-1, 0), (1, 0), (0, -1), (0, 1)]:
+                        nx, ny = x + dx, y + dy
+                        if self.board.in_bounds(nx, ny):
+                            if self.board.get_cell(nx, ny) == player_board_idx:
+                                edge_invalid = True
+                                break
+                    if edge_invalid:
+                        valid = False
+                        break
+                if not valid:
+                    continue
+
                 mask[action_idx] = True
 
         return mask
@@ -240,11 +295,14 @@ class BlokusGame:
         if not player.can_move:
             return False
 
-        for action_idx in range(self.num_actions):
-            move = self._action_moves[action_idx]
-            piece = self.piece_set.get_piece(move.piece_id)
-            if piece.name in player.available_pieces:
-                if self.valid_move(player_idx, move):
+        available_piece_ids = [
+            self.piece_set.get_piece_id(name)
+            for name in player.available_pieces
+        ]
+
+        for piece_id in available_piece_ids:
+            for action_idx in self._actions_by_piece[piece_id]:
+                if self.valid_move(player_idx, self._action_moves[action_idx]):
                     return True
         return False