fix: user location fix

internal/service/reminder_service.go

@@ -51,15 +51,17 @@ const (
 type ReminderService struct {
 	repo      *repository.ReminderRepo
 	prefs     *repository.NotificationPrefsRepo
+	users     *repository.UserRepo
 	notif     *NotificationService
 	logger    *zap.Logger
 	sadhnaURL string
 }
 
-func NewReminderService(repo *repository.ReminderRepo, prefs *repository.NotificationPrefsRepo, notif *NotificationService, logger *zap.Logger, frontendURL string) *ReminderService {
+func NewReminderService(repo *repository.ReminderRepo, prefs *repository.NotificationPrefsRepo, users *repository.UserRepo, notif *NotificationService, logger *zap.Logger, frontendURL string) *ReminderService {
 	return &ReminderService{
 		repo:      repo,
 		prefs:     prefs,
+		users:     users,
 		notif:     notif,
 		logger:    logger,
 		sadhnaURL: strings.TrimRight(frontendURL, "/") + "/sadhna-streak",
@@ -116,7 +118,21 @@ func (s *ReminderService) SetTimezone(ctx context.Context, userID, tz string) er
 	if _, err := time.LoadLocation(tz); err != nil {
 		return ErrInvalidTimezone
 	}
-	return s.repo.SetTimezone(ctx, userID, tz)
+	if err := s.repo.SetTimezone(ctx, userID, tz); err != nil {
+		return err
+	}
+	// Best-effort: backfill the account country from the timezone when it's
+	// still unset (geo-IP at login is the primary source; SetCountryIfEmpty
+	// never overwrites it). A no-op when the zone isn't in the table.
+	if s.users != nil {
+		if cc := tzCountry[tz]; cc != "" {
+			if err := s.users.SetCountryIfEmpty(ctx, userID, cc); err != nil {
+				s.logger.Warn("backfill country from timezone failed",
+					zap.String("user", userID), zap.String("country", cc), zap.Error(err))
+			}
+		}
+	}
+	return nil
 }
 
 // RunOnce evaluates every due candidate against `now` and fires the reminders