Enhance Notification and User Services with Improved Error Handling and Data Consistency

- Updated GetByID methods in user and customer services to return specific "not found" errors for better clarity in error responses.
- Modified NotificationResponse structure to include a new Recipient field, allowing for more flexible recipient handling.
- Changed CreatedAt and UpdatedAt fields in NotificationResponse to use Unix timestamps (int64) for consistency across the application.
- Improved notification retrieval logic to handle potential nil values for user and customer lookups, ensuring robust data handling.

internal/notification/service.go

@@ -192,17 +192,31 @@ func (s *notificationService) GetNotifications(ctx context.Context, req *SearchF
 
 	notificationsResponse := make([]*NotificationResponse, 0)
 	for _, notification := range notifications.Data {
-		createdAt, err := time.Parse(time.RFC3339, notification.CreatedAt)
-		if err != nil {
-			return nil, err
+		createdAt, _ := time.Parse(time.RFC3339, notification.CreatedAt)
+		createdAtUnix := createdAt.Unix()
+		updatedAt, _ := time.Parse(time.RFC3339, notification.UpdatedAt)
+		updatedAtUnix := updatedAt.Unix()
+		if createdAtUnix < 0 {
+			createdAtUnix = 0
 		}
-		updatedAt, err := time.Parse(time.RFC3339, notification.UpdatedAt)
-		if err != nil {
-			return nil, err
+		if updatedAtUnix < 0 {
+			updatedAtUnix = 0
 		}
+
+		usr, _ := s.userService.GetUserByID(ctx, notification.UserID)
+		cust, _ := s.customerService.GetByID(ctx, notification.UserID)
+
+		var recipient any
+		if usr != nil {
+			recipient = usr
+		} else if cust != nil {
+			recipient = cust
+		}
+
 		notificationsResponse = append(notificationsResponse, &NotificationResponse{
 			ID:          notification.ID,
 			UserID:      notification.UserID,
+			Recipient:   recipient,
 			Title:       notification.Title,
 			Message:     notification.Message,
 			Link:        &notification.Link,
@@ -218,8 +232,8 @@ func (s *notificationService) GetNotifications(ctx context.Context, req *SearchF
 			Seen:        notification.Seen,
 			SeenAt:      notification.SeenAt,
 			ScheduledAt: notification.ScheduledAt,
-			CreatedAt:   createdAt,
-			UpdatedAt:   updatedAt,
+			CreatedAt:   createdAtUnix,
+			UpdatedAt:   updatedAtUnix,
 		})
 	}
 
@@ -260,9 +274,29 @@ func (s *notificationService) GetNotification(ctx context.Context, notificationI
 		imagePtr = &notification.Data.Image
 	}
 
+	usr, _ := s.userService.GetUserByID(ctx, notification.Data.UserID)
+	cust, _ := s.customerService.GetByID(ctx, notification.Data.UserID)
+
+	var recipient any
+	if usr != nil {
+		recipient = usr
+	} else if cust != nil {
+		recipient = cust
+	}
+
+	createdAt := notification.Data.CreatedAt.Unix()
+	updatedAt := notification.Data.UpdatedAt.Unix()
+	if createdAt < 0 {
+		createdAt = 0
+	}
+	if updatedAt < 0 {
+		updatedAt = 0
+	}
+
 	detailedResponse := &NotificationResponse{
 		ID:          notification.Data.ID,
 		UserID:      notification.Data.UserID,
+		Recipient:   recipient,
 		Title:       notification.Data.Title,
 		Message:     notification.Data.Message,
 		Link:        linkPtr,
@@ -270,8 +304,8 @@ func (s *notificationService) GetNotification(ctx context.Context, notificationI
 		Type:        notification.Data.Type,
 		Priority:    notification.Data.Priority,
 		EventType:   notification.Data.EventType,
-		CreatedAt:   notification.Data.CreatedAt,
-		UpdatedAt:   notification.Data.UpdatedAt,
+		CreatedAt:   createdAt,
+		UpdatedAt:   updatedAt,
 		Methods:     notification.Data.Methods,
 		Metadata:    notification.Data.Metadata,
 		Status:      notification.Data.Status,