game: core: use server game calulation form

games/objects/GameManager.py

@@ -0,0 +1,22 @@
+
+from .Game import Game
+from ..models import GameModel
+
+class GameManager():
+    
+    def __init__(self) -> None:
+        self._game_list: [Game] = []
+    
+    def get(self, game_id: int):
+        
+        if (not GameModel.objects.filter(pk = game_id, started = True, finished = False).exists()):
+            return None
+        
+        for game in self._game_list:
+            game: Game
+            if (game.game_id == game_id):
+                return game
+        
+        return Game(game_id)
+            
+