feat: sync configurable OTP delivery providers

internal/otpdelivery/smtp/sender_test.go

@@ -0,0 +1,31 @@
+package smtp
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"telesrv/internal/otpdelivery"
+)
+
+func TestSenderRejectsNonEmailChannelBeforeDial(t *testing.T) {
+	sender := New(Config{Host: "smtp.example.test", Port: 25, From: "noreply@example.test"})
+	_, err := sender.Deliver(context.Background(), otpdelivery.Request{
+		DeliveryID: "otp_sms",
+		Purpose:    otpdelivery.PurposeLoginSMS,
+		Channel:    otpdelivery.ChannelSMS,
+		Recipient:  "15550001001",
+		Code:       "12345",
+		ExpiresAt:  time.Now().Add(time.Minute),
+	})
+	if err == nil || !strings.Contains(err.Error(), "cannot deliver") {
+		t.Fatalf("err = %v", err)
+	}
+}
+
+func TestHumanTTLRoundsNetworkSkew(t *testing.T) {
+	if got := humanTTL(5*time.Minute - 200*time.Millisecond); got != "5 minutes" {
+		t.Fatalf("humanTTL = %q", got)
+	}
+}