package com.bookshop.solid.srp;

import java.util.ArrayList;
import java.util.List;

/** Responsibility 3: storage. Swapping this for a database touches no other class. */
public class ReceiptRepository {

    private final List<Receipt> saved = new ArrayList<>();

    public void save(Receipt receipt) {
        saved.add(receipt);
    }

    public List<Receipt> findByCustomer(String customerId) {
        return saved.stream().filter(r -> r.customer().id().equals(customerId)).toList();
    }
}

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