Add Resend mailer as primary with SMTP fallback for reliable email delivery

src/env.ts

@@ -11,6 +11,8 @@ const schema = z.object({
   DATABASE_CONNECT_TIMEOUT_MS: z.coerce.number().int().positive().default(10_000),
   HOTEL_NAME: z.string().default("Atom"),
   APP_URL: z.string().url().default("http://localhost:3000"),
+  // Resend API key (preferred — simpler HTTP API, always works).
+  RESEND_API_KEY: z.string().optional(),
   // SMTP (password reset / notifications). Email features no-op if unset.
   SMTP_HOST: z.string().optional(),
   SMTP_PORT: z.coerce.number().int().positive().optional(),

src/lib/services/email.ts

@@ -1,7 +1,9 @@
 import nodemailer, { type Transporter } from "nodemailer";
+import { Resend } from "resend";
 import { env } from "@/env";
 
 let transporter: Transporter | null = null;
+let resend: Resend | null = null;
 
 function getTransport(): Transporter | null {
   if (!env.SMTP_HOST) return null;
@@ -16,23 +18,38 @@ function getTransport(): Transporter | null {
   return transporter;
 }
 
-/** Send an HTML email. No-ops (returns false) when SMTP isn't configured. */
+function getResend(): Resend | null {
+  if (!env.RESEND_API_KEY) return null;
+  if (!resend) resend = new Resend(env.RESEND_API_KEY);
+  return resend;
+}
+
+/** Send an HTML email. Tries Resend first, then SMTP. Returns false if both are unconfigured. */
 export async function sendMail(to: string, subject: string, html: string): Promise<boolean> {
+  const from = env.SMTP_FROM ?? `no-reply@${env.HOTEL_NAME}`;
+
+  const r = getResend();
+  if (r) {
+    try {
+      await r.emails.send({ from, to, subject, html });
+      return true;
+    } catch (e) {
+      console.error("[email] Resend failed:", (e as Error).message);
+    }
+  }
+
   const t = getTransport();
-  if (!t) {
-    console.warn("[email] SMTP not configured — skipping mail to", to);
-    return false;
+  if (t) {
+    try {
+      await t.sendMail({ from, to, subject, html });
+      return true;
+    } catch (e) {
+      console.error("[email] SMTP failed:", (e as Error).message);
+    }
   }
-  try {
-    await t.sendMail({
-      from: env.SMTP_FROM ?? `no-reply@${env.HOTEL_NAME}`,
-      to,
-      subject,
-      html,
-    });
-    return true;
-  } catch (e) {
-    console.error("[email] send failed:", (e as Error).message);
-    return false;
+
+  if (!r && !t) {
+    console.warn("[email] No mailer configured — set RESEND_API_KEY or SMTP_HOST");
   }
+  return false;
 }