import pygame

class BaseScene:
    def __init__(self, screen: pygame.Surface):
        """
        初始化场景，接收并保存画布、计时器
        """
        self.screen = screen
        self.next_scene = None

    def update(self, dt=0):
        """
        场景的每帧更新逻辑
        """
        pass

    def handle_event(self, events):
        """
        接收主循环传来的事件并处理
        """
        pass

    def switch_to_scene(self, scene_name):
        """
        切换场景
        """
        self.next_scene = scene_name

    def exit(self):
        """
        退出游戏
        """
        self.next_scene = "exit"