feat: mail service

authsession/internal/service/sendemailcode/service.go

@@ -20,6 +20,11 @@ type Input struct {
 	// Email is the user-supplied e-mail address that should receive the login
 	// code.
 	Email string
+
+	// AcceptLanguage stores the optional public Accept-Language header forwarded
+	// by gateway for auth-mail localization and create-only registration
+	// context.
+	AcceptLanguage string
 }
 
 // Result describes one public send-email-code response.
@@ -160,6 +165,7 @@ func (s *Service) Execute(ctx context.Context, input Input) (result Result, err
 	if err != nil {
 		return Result{}, err
 	}
+	preferredLanguage := shared.ResolvePreferredLanguage(input.AcceptLanguage)
 
 	now := s.clock.Now().UTC()
 	abuseResult, err := s.abuseProtector.CheckAndReserve(ctx, ports.SendEmailCodeAbuseInput{
@@ -191,13 +197,14 @@ func (s *Service) Execute(ctx context.Context, input Input) (result Result, err
 		return Result{}, shared.InternalError(err)
 	}
 	pending := challenge.Challenge{
-		ID:            challengeID,
-		Email:         email,
-		CodeHash:      codeHash,
-		Status:        pendingStatus,
-		DeliveryState: pendingDeliveryState,
-		CreatedAt:     now,
-		ExpiresAt:     now.Add(challenge.InitialTTL),
+		ID:                challengeID,
+		Email:             email,
+		CodeHash:          codeHash,
+		PreferredLanguage: preferredLanguage,
+		Status:            pendingStatus,
+		DeliveryState:     pendingDeliveryState,
+		CreatedAt:         now,
+		ExpiresAt:         now.Add(challenge.InitialTTL),
 	}
 	if err := pending.Validate(); err != nil {
 		return Result{}, shared.InternalError(err)
@@ -240,8 +247,10 @@ func (s *Service) Execute(ctx context.Context, input Input) (result Result, err
 		return result, err
 	default:
 		deliveryResult, err := s.mailSender.SendLoginCode(ctx, ports.SendLoginCodeInput{
-			Email: email,
-			Code:  code,
+			Email:          email,
+			IdempotencyKey: challengeID.String(),
+			Code:           code,
+			Locale:         preferredLanguage,
 		})
 		if err != nil {
 			final.Status = challenge.StatusFailed