OpenIsle/backend/src/main/java/com/openisle/service/PushNotificationService.java

package com.openisle.service;

import com.openisle.model.PushSubscription;
import com.openisle.model.User;
import com.openisle.repository.PushSubscriptionRepository;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.security.Security;
import java.util.List;
import lombok.extern.slf4j.Slf4j;
import nl.martijndwars.webpush.Notification;
import nl.martijndwars.webpush.PushService;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.jose4j.lang.JoseException;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

@Slf4j
@Service
public class PushNotificationService {

  private final PushSubscriptionRepository subscriptionRepository;
  private final PushService pushService;

  public PushNotificationService(
    PushSubscriptionRepository subscriptionRepository,
    @Value("${app.webpush.public-key:}") String publicKey,
    @Value("${app.webpush.private-key:}") String privateKey
  ) throws GeneralSecurityException {
    this.subscriptionRepository = subscriptionRepository;
    if (publicKey != null && !publicKey.isBlank() && privateKey != null && !privateKey.isBlank()) {
      Security.addProvider(new BouncyCastleProvider());
      this.pushService = new PushService(publicKey, privateKey);
    } else {
      this.pushService = null;
    }
  }

  public void sendNotification(User user, String payload) {
    if (pushService == null) {
      log.warn("Push notifications are disabled because VAPID keys are not configured.");
      return;
    }
    List<PushSubscription> subs = subscriptionRepository.findByUser(user);
    for (PushSubscription sub : subs) {
      try {
        Notification notification = new Notification(
          sub.getEndpoint(),
          sub.getP256dh(),
          sub.getAuth(),
          payload
        );
        pushService.send(notification);
      } catch (
        GeneralSecurityException
        | IOException
        | JoseException
        | InterruptedException
        | java.util.concurrent.ExecutionException e
      ) {
        log.error(e.getMessage());
      }
    }
  }
}