TASK: Implement game handler as singleton

Author: devcarron

gamehandler.py

@@ -11,64 +11,79 @@
 
 # game_handler handles the blackJack-game-objects. When a new game is created, it is saved in the "game_list"
 class GameHandler(object):
-    GameList = []  # List, where the running Games are stored in
-
-    def gl_create(self) -> None:
-        self.GameList = []
-
-    def gl_remove(self, chat_id: int) -> None:
-        index = self.get_index_by_chatid(chat_id)
-        if index is None:
-            return
-        if not index < 0:
-            self.GameList.pop(index)
-
-    def add_game(self, blackjackgame: BlackJackGame) -> None:
-        self.GameList.append(blackjackgame)
-
-    def get_index_by_chatid(self, chat_id: int) -> Optional[int]:
-        for index, game in enumerate(self.GameList):
-            if game.chat_id == chat_id:
-                return index
-            else:
-                for player in game.players:
-                    if player.user_id == chat_id:
-                        return index
-
-        return None
-
-    def get_game_by_chatid(self, chat_id: int) -> Optional[BlackJackGame]:
-        index = self.get_index_by_chatid(chat_id)
-        if index is None:
+    class __GameHandler(object):
+        def __init__(self):
+            self.game_list = []  # List, where the running Games are stored in
+            pass
+
+        def gl_create(self) -> None:
+            self.game_list = []
+
+        def gl_remove(self, chat_id: int) -> None:
+            index = self.get_index_by_chatid(chat_id)
+            if index is None:
+                return
+            if not index < 0:
+                self.game_list.pop(index)
+
+        def get_index_by_chatid(self, chat_id: int) -> Optional[int]:
+            for index, game in enumerate(self.game_list):
+                if game.chat_id == chat_id:
+                    return index
+                else:
+                    for player in game.players:
+                        if player.user_id == chat_id:
+                            return index
+
             return None
-        return self.GameList[index]
 
-    def get_game_by_index(self, index: int) -> BlackJackGame:
-        return self.GameList[index]
+        def add_game(self, blackjackgame: BlackJackGame) -> None:
+            self.game_list.append(blackjackgame)
 
-    def get_game_by_id(self, game_id: int) -> Optional[BlackJackGame]:
-        if game_id is None:
-            return None
-        for game in self.GameList:
-            if game.game_id == game_id:
-                return game
-        return None
+        def get_game_by_chatid(self, chat_id: int) -> Optional[BlackJackGame]:
+            index = self.get_index_by_chatid(chat_id)
+            if index is None:
+                return None
+            return self.game_list[index]
 
-    def generate_id(self) -> str:
-        game_id = ''.join(random.choice(string.digits + string.ascii_letters) for _ in range(8))
+        def get_game_by_index(self, index: int) -> BlackJackGame:
+            return self.game_list[index]
+
+        def get_game_by_id(self, game_id: int) -> Optional[BlackJackGame]:
+            if game_id is None:
+                return None
+            for game in self.game_list:
+                if game.game_id == game_id:
+                    return game
+            return None
 
-        while self.id_already_existing(game_id):
-            print("ID already existing: " + str(game_id))
+        def generate_id(self) -> str:
+            """Generates a random ID for a game"""
             game_id = ''.join(random.choice(string.digits + string.ascii_letters) for _ in range(8))
 
-        return game_id
+            while self.id_already_existing(game_id):
+                print("ID already existing: " + str(game_id))
+                game_id = ''.join(random.choice(string.digits + string.ascii_letters) for _ in range(8))
 
-    def id_already_existing(self, game_id: str) -> bool:
-        for game in self.GameList:
-            if game.game_id == game_id:
-                return True
+            return game_id
 
-        return False
+        def id_already_existing(self, game_id: str) -> bool:
+            """Checks if an ID is already existing in the list of games"""
+            for game in self.game_list:
+                if game.game_id == game_id:
+                    return True
+
+            return False
+
+    instance = None
 
     def __init__(self):
-        self.GameList = []
+        if not GameHandler.instance:
+            GameHandler.instance = GameHandler.__GameHandler()
+
+    @staticmethod
+    def get_instance() -> __GameHandler:
+        if not GameHandler.instance:
+            GameHandler.instance = GameHandler.__GameHandler()
+
+        return GameHandler.instance

main.py

@@ -32,7 +32,7 @@
 updater = Updater(token=BOT_TOKEN)
 dispatcher = updater.dispatcher
 
-game_handler = GameHandler()
+game_handler = GameHandler().get_instance()
 tg_bot = updater.bot