From 18556c818dce97494c9f77b745814f8fc77bb8fd Mon Sep 17 00:00:00 2001
From: Marc Mintel <marc@mintel.me>
Date: Fri, 10 Apr 2026 12:58:04 +0200
Subject: [PATCH] fix(mail): harden mailer and fix missing notification
 recipients

---
 app/actions/contact.ts | 14 ++++++++----
 lib/env.ts             |  2 +-
 lib/mail/mailer.ts     | 49 +++++++++++++++++++++++++++++++++++-------
 package.json           |  2 +-
 4 files changed, 53 insertions(+), 14 deletions(-)

diff --git a/app/actions/contact.ts b/app/actions/contact.ts
index 3f2e3783..688af6db 100644
--- a/app/actions/contact.ts
+++ b/app/actions/contact.ts
@@ -95,6 +95,7 @@ export async function sendContactFormAction(formData: FormData) {
     );
 
     if (!isTestSubmission) {
+      logger.info('Sending internal notification', { recipients: config.mail.recipients });
       const notificationResult = await sendEmail({
         replyTo: email,
         subject: notificationSubject,
@@ -106,14 +107,18 @@ export async function sendContactFormAction(formData: FormData) {
           messageId: notificationResult.messageId,
         });
       } else {
-        logger.error('Notification email FAILED', {
+        logger.error('Notification email DELIVERY FAILED', {
           error: notificationResult.error,
           subject: notificationSubject,
-          email,
+          recipients: config.mail.recipients,
         });
         services.errors.captureException(
           new Error(`Notification email failed: ${notificationResult.error}`),
-          { action: 'sendContactFormAction_notification', email },
+          { 
+            action: 'sendContactFormAction_notification', 
+            email, 
+            recipients: config.mail.recipients 
+          },
         );
       }
     } else {
@@ -130,6 +135,7 @@ export async function sendContactFormAction(formData: FormData) {
     );
 
     if (!isTestSubmission) {
+      logger.info('Sending customer confirmation', { to: email });
       const confirmationResult = await sendEmail({
         to: email,
         subject: confirmationSubject,
@@ -141,7 +147,7 @@ export async function sendContactFormAction(formData: FormData) {
           messageId: confirmationResult.messageId,
         });
       } else {
-        logger.error('Confirmation email FAILED', {
+        logger.error('Confirmation email DELIVERY FAILED', {
           error: confirmationResult.error,
           subject: confirmationSubject,
           to: email,
diff --git a/lib/env.ts b/lib/env.ts
index f6a4ed1d..b989cc84 100644
--- a/lib/env.ts
+++ b/lib/env.ts
@@ -42,7 +42,7 @@ const envExtension = {
   MAIL_USERNAME: z.string().optional(),
   MAIL_PASSWORD: z.string().optional(),
   MAIL_FROM: z.string().optional(),
-  MAIL_RECIPIENTS: z.string().optional(),
+  MAIL_RECIPIENTS: z.string().trim().optional(),
 };
 
 /**
diff --git a/lib/mail/mailer.ts b/lib/mail/mailer.ts
index ffe8f5d1..d766b7dc 100644
--- a/lib/mail/mailer.ts
+++ b/lib/mail/mailer.ts
@@ -32,16 +32,27 @@ interface SendEmailOptions {
 }
 
 export async function sendEmail({ to, replyTo, subject, html }: SendEmailOptions) {
-  const recipients = to || config.mail.recipients;
   const logger = getServerAppServices().logger.child({ component: 'mailer' });
+  
+  // Resolve recipients: priority to 'to' override, fallback to global MAIL_RECIPIENTS
+  const resolvedTo = to || config.mail.recipients;
+  
+  // Normalize recipients (handle arrays or comma-strings)
+  const recipients = Array.isArray(resolvedTo) 
+    ? resolvedTo.join(', ') 
+    : (resolvedTo?.toString() || '');
 
-  if (!recipients) {
-    logger.error('No email recipients configured (MAIL_RECIPIENTS is empty and no "to" provided)', { subject });
+  if (!recipients || recipients.trim() === '') {
+    logger.error('Email delivery ABORTED: No recipients configured', { 
+      subject, 
+      providedTo: to,
+      configRecipients: config.mail.recipients 
+    });
     return { success: false as const, error: 'No recipients configured' };
   }
 
   if (!config.mail.from) {
-    logger.error('MAIL_FROM is not configured — cannot send email', { subject, recipients });
+    logger.error('Email delivery ABORTED: MAIL_FROM is missing', { subject, recipients });
     return { success: false as const, error: 'MAIL_FROM is not configured' };
   }
 
@@ -53,14 +64,36 @@ export async function sendEmail({ to, replyTo, subject, html }: SendEmailOptions
     html,
   };
 
-
   try {
-    const info = await getTransporter().sendMail(mailOptions);
-    logger.info('Email sent successfully', { messageId: info.messageId, subject, recipients });
+    const transporter = getTransporter();
+    logger.info('Attempting to send email via SMTP', { 
+      host: config.mail.host,
+      subject, 
+      recipients,
+      hasReplyTo: !!replyTo 
+    });
+
+    const info = await transporter.sendMail(mailOptions);
+    
+    logger.info('Email sent successfully', { 
+      messageId: info.messageId, 
+      subject, 
+      recipients,
+      response: info.response 
+    });
+    
     return { success: true, messageId: info.messageId };
   } catch (error) {
     const errorMsg = error instanceof Error ? error.message : String(error);
-    logger.error('Error sending email', { error: errorMsg, subject, recipients });
+    logger.error('SMTP Transport failed', { 
+      error: errorMsg, 
+      subject, 
+      recipients,
+      config: {
+        host: config.mail.host,
+        user: config.mail.user ? '***' : 'not set'
+      }
+    });
     return { success: false, error: errorMsg };
   }
 }
diff --git a/package.json b/package.json
index 08d44fe7..846d1ff0 100644
--- a/package.json
+++ b/package.json
@@ -160,7 +160,7 @@
     "prepare": "husky",
     "preinstall": "npx only-allow pnpm"
   },
-  "version": "2.3.11",
+  "version": "2.3.12",
   "pnpm": {
     "onlyBuiltDependencies": [
       "@parcel/watcher",