"""规则注册机制：新增规则只需写一个 validator 函数 + @register_rule 装饰器"""

RULE_REGISTRY = {}


def register_rule(rule_type):
    """装饰器：注册规则类型"""
    def decorator(func):
        RULE_REGISTRY[rule_type] = func
        return func
    return decorator


def get_all_rule_types():
    """返回所有已注册的规则类型"""
    return list(RULE_REGISTRY.keys())


def get_rule_validator(rule_type):
    """根据类型获取 validator 函数"""
    return RULE_REGISTRY.get(rule_type)