package factorymethod;

public abstract class NotificationSender {

    // THE factory method — this is the one thing subclasses override.
    // It returns a Notification (the Product interface), never a concrete class.
    protected abstract Notification createNotification();

    // The shared workflow — marked final so subclasses cannot change it.
    // It calls createNotification() to get the right notification,
    // then runs the same steps every time regardless of which channel was created.
    public final void notify(String recipient, String message) {
        Notification notification = createNotification();     // delegate creation
        System.out.println("Sending " + notification.getType() + " notification...");
        notification.send(recipient, message);                // use the Product interface
        System.out.println("Delivered.");
    }

    // Shared retry logic — works for all channels without change
    public void notifyWithRetry(String recipient, String message, int maxRetries) {
        for (int attempt = 1; attempt <= maxRetries; attempt++) {
            try {
                notify(recipient, message);
                return; // success — exit
            } catch (Exception e) {
                System.err.printf("Attempt %d failed: %s%n", attempt, e.getMessage());
            }
        }
        throw new RuntimeException("All " + maxRetries + " attempts failed");
    }
}