oop-solid-design-patterns/problem7_adapter.py at main · khadijafatima409/oop-solid-design-patterns · GitHub

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"""
Problem 7: Adapter Pattern
"""

from abc import ABC, abstractmethod


class PaymentProcessor(ABC):
    @abstractmethod
    def process(self, amount, currency): pass


class LegacyPaymentService:
    def make_payment(self, amount_in_dollars):
        print(f"Legacy payment of ${amount_in_dollars}")


class LegacyPaymentAdapter(PaymentProcessor):
    def __init__(self, legacy_service):
        self.legacy_service = legacy_service

    def process(self, amount, currency):
        if currency != "USD":
            amount = amount / 280  # simple conversion
        self.legacy_service.make_payment(amount)


class ModernPaymentService(PaymentProcessor):
    def process(self, amount, currency):
        print(f"Modern payment: {amount} {currency}")


class PaymentSystem:
    def __init__(self, processor: PaymentProcessor):
        self.processor = processor

    def pay(self, amount, currency):
        self.processor.process(amount, currency)


if __name__ == "__main__":
    modern = PaymentSystem(ModernPaymentService())
    modern.pay(100, "USD")

    legacy = PaymentSystem(LegacyPaymentAdapter(LegacyPaymentService()))
    legacy.pay(28000, "PKR")