Bridge 模式

from abc import ABC, abstractmethod
from typing import Protocol


class MessageSender(Protocol):
    """实现者接口：消息发送器"""

    def send(self, message: str, recipient: str) -> None:
        ...


class EmailSender:
    """具体实现：邮件发送"""

    def send(self, message: str, recipient: str) -> None:
        print(f"发送邮件到 {recipient}: {message}")


class SMSSender:
    """具体实现：短信发送"""

    def send(self, message: str, recipient: str) -> None:
        print(f"发送短信到 {recipient}: {message}")


class PushNotificationSender:
    """具体实现：推送通知"""

    def send(self, message: str, recipient: str) -> None:
        print(f"推送通知到 {recipient}: {message}")


class NotificationSystem:
    """抽象类：通知系统"""

    def __init__(self, sender: MessageSender):
        self.sender = sender

    def notify(self, message: str, recipient: str) -> None:
        """发送通知的模板方法"""
        self.sender.send(message, recipient)


class AlertSystem(NotificationSystem):
    """扩展抽象：告警系统"""

    def send_alert(self, level: str, message: str, recipient: str) -> None:
        formatted_msg = f"[{level} 告警] {message}"
        self.notify(formatted_msg, recipient)


class MarketingSystem(NotificationSystem):
    """扩展抽象：营销系统"""

    def send_promotion(self, product: str, discount: int, recipient: str) -> None:
        formatted_msg = f"{product} 特惠！立减 {discount} 元！"
        self.notify(formatted_msg, recipient)


# 使用
def main():
    # 使用邮件发送告警
    email_alert = AlertSystem(EmailSender())
    email_alert.send_alert("紧急", "服务器CPU使用率过高", "admin@example.com")

    # 使用短信发送营销信息
    sms_marketing = MarketingSystem(SMSSender())
    sms_marketing.send_promotion("Python课程", 100, "13800138000")

    # 使用推送发送通知
    push_alert = AlertSystem(PushNotificationSender())
    push_alert.send_alert("警告", "检测到异常登录", "user123")


if __name__ == "__main__":
    main()

from abc import ABC, abstractmethod
from typing import Protocol


class PaymentMethod(Protocol):
    """实现者接口：支付渠道"""

    def process(self, amount: float) -> bool:
        ...

    def get_balance(self) -> float:
        ...


class CreditCard:
    """信用卡支付"""

    def __init__(self, limit: float):
        self._limit = limit
        self._used = 0

    def process(self, amount: float) -> bool:
        if self._limit - self._used >= amount:
            self._used += amount
            print(f"信用卡支付 {amount} 元成功")
            return True
        print(f"信用卡额度不足，支付失败")
        return False

    def get_balance(self) -> float:
        return self._limit - self._used


class WeChatPay:
    """微信支付"""

    def __init__(self, balance: float):
        self._balance = balance

    def process(self, amount: float) -> bool:
        if self._balance >= amount:
            self._balance -= amount
            print(f"微信支付 {amount} 元成功")
            return True
        print(f"微信余额不足，支付失败")
        return False

    def get_balance(self) -> float:
        return self._balance


class Alipay:
    """支付宝"""

    def __init__(self, balance: float):
        self._balance = balance

    def process(self, amount: float) -> bool:
        if self._balance >= amount:
            self._balance -= amount
            print(f"支付宝支付 {amount} 元成功")
            return True
        print(f"支付宝余额不足，支付失败")
        return False

    def get_balance(self) -> float:
        return self._balance


class Payment(ABC):
    """抽象类：支付"""

    def __init__(self, method: PaymentMethod):
        self.method = method

    @abstractmethod
    def make_payment(self, amount: float) -> bool:
        pass


class OnlineShopping(Payment):
    """扩展抽象：网购支付"""

    def make_payment(self, amount: float) -> bool:
        print(f"=== 网购订单支付 ===")
        print(f"订单金额: {amount} 元")
        print(f"支付方式余额: {self.method.get_balance()} 元")
        success = self.method.process(amount)
        if success:
            print("订单支付成功，等待发货")
        else:
            print("订单支付失败，请更换支付方式")
        return success


class UtilityBill(Payment):
    """扩展抽象：生活缴费"""

    def make_payment(self, amount: float) -> bool:
        print(f"=== 生活缴费 ===")
        print(f"缴费金额: {amount} 元")
        success = self.method.process(amount)
        if success:
            print("缴费成功")
        else:
            print("缴费失败")
        return success


# 使用
def main():
    # 创建支付方式
    credit_card = CreditCard(10000)
    wechat = WeChatPay(500)
    alipay = Alipay(200)

    # 网购使用信用卡
    shopping1 = OnlineShopping(credit_card)
    shopping1.make_payment(2999)

    # 网购使用微信
    shopping2 = OnlineShopping(wechat)
    shopping2.make_payment(199)

    # 缴费使用支付宝
    bill = UtilityBill(alipay)
    bill.make_payment(150)


if __name__ == "__main__":
    main()