fix: resolve duplicate FCM service and add SendMulticast method

backend/internal/infrastructure/notifications/fcm.go

@@ -1,78 +0,0 @@
-package notifications
-
-import (
-	"context"
-	"fmt"
-	"log"
-
-	firebase "firebase.google.com/go/v4"
-	"firebase.google.com/go/v4/messaging"
-	"google.golang.org/api/option"
-)
-
-type FCMService struct {
-	app    *firebase.App
-	client *messaging.Client
-}
-
-func NewFCMService(serviceAccountJSON []byte) (*FCMService, error) {
-	ctx := context.Background()
-	opt := option.WithCredentialsJSON(serviceAccountJSON)
-	
-	app, err := firebase.NewApp(ctx, nil, opt)
-	if err != nil {
-		return nil, fmt.Errorf("error initializing firebase app: %w", err)
-	}
-
-	client, err := app.Messaging(ctx)
-	if err != nil {
-		return nil, fmt.Errorf("error getting messaging client: %w", err)
-	}
-
-	return &FCMService{
-		app:    app,
-		client: client,
-	}, nil
-}
-
-func (s *FCMService) SendPush(ctx context.Context, token, title, body string, data map[string]string) error {
-	message := &messaging.Message{
-		Token: token,
-		Notification: &messaging.Notification{
-			Title: title,
-			Body:  body,
-		},
-		Data: data,
-	}
-
-	response, err := s.client.Send(ctx, message)
-	if err != nil {
-		return fmt.Errorf("error sending fcm message: %w", err)
-	}
-
-	log.Printf("Successfully sent fcm message: %s", response)
-	return nil
-}
-
-func (s *FCMService) SendMulticast(ctx context.Context, tokens []string, title, body string, data map[string]string) error {
-	if len(tokens) == 0 {
-		return nil
-	}
-
-	message := &messaging.MulticastMessage{
-		Tokens: tokens,
-		Notification: &messaging.Notification{
-			Title: title,
-			Body:  body,
-		},
-		Data: data,
-	}
-
-	br, err := s.client.SendEachForMulticast(ctx, message)
-	if err != nil {
-		return fmt.Errorf("error sending multicast message: %w", err)
-	}
-
-	log.Printf("Multicast results: %d successes, %d failures", br.SuccessCount, br.FailureCount)
-	return nil
-}

backend/internal/services/fcm_service.go

@@ -123,6 +123,29 @@ func (s *FCMService) Send(token, title, body string, data map[string]string) err
 	return s.SendPush(context.Background(), token, title, body, data)
 }
 
+func (s *FCMService) SendMulticast(ctx context.Context, tokens []string, title, body string, data map[string]string) error {
+	if len(tokens) == 0 {
+		return nil
+	}
+
+	client, err := s.getClient(ctx)
+	if err != nil {
+		return err
+	}
+
+	message := &messaging.MulticastMessage{
+		Tokens: tokens,
+		Notification: &messaging.Notification{
+			Title: title,
+			Body:  body,
+		},
+		Data: data,
+	}
+
+	_, err = client.SendEachForMulticast(ctx, message)
+	return err
+}
+
 // SubscribeToTopic subscribes a token to a topic
 func (s *FCMService) SubscribeToTopic(ctx context.Context, tokens []string, topic string) error {
 	client, err := s.getClient(ctx)