Render inbound email HTML body in admin inbox

Worker now extracts both text/plain and text/html MIME parts and sends
htmlBody in the webhook payload. Server stores it on the submission.
Admin inbox renders htmlBody in a sandboxed iframe when present, falling
back to plain text with whitespace preserved.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cloudflare/email-worker.js

@@ -84,37 +84,39 @@ function parseEmail(raw, message) {
   const date = headers['date'] ?? new Date().toISOString()
   const messageId = headers['message-id'] ?? ''
 
-  // Extract plain text body — skip MIME boundaries and HTML parts
   const bodyLines = lines.slice(bodyStart)
-  const plainText = extractPlainText(raw, bodyLines)
+  const plainText = extractPart(raw, bodyLines, 'text/plain')
+  const htmlBody = extractPart(raw, bodyLines, 'text/html')
 
   return {
     from,
     to,
     subject,
     body: plainText,
+    htmlBody: htmlBody || null,
     date,
     messageId,
     source: 'inbound-email',
   }
 }
 
-function extractPlainText(raw, bodyLines) {
-  // Look for Content-Type: text/plain section in multipart emails
-  const textPlainMatch = /Content-Type: text\/plain[^\r\n]*\r?\n(?:[^\r\n]+\r?\n)*\r?\n([\s\S]*?)(?=--|\z)/i.exec(raw)
-  if (textPlainMatch) {
-    return decodeEmailBody(textPlainMatch[1]).trim()
-  }
+function extractPart(raw, bodyLines, contentType) {
+  const escaped = contentType.replace('/', '\\/')
+  const re = new RegExp(`Content-Type: ${escaped}[^\\r\\n]*\\r?\\n(?:[^\\r\\n]+\\r?\\n)*\\r?\\n([\\s\\S]*?)(?=--|$)`, 'i')
+  const match = re.exec(raw)
+  if (match) return decodeEmailBody(match[1]).trim()
 
-  // Fallback: join body lines, strip HTML tags if present
+  if (contentType === 'text/plain') {
     const joined = bodyLines.join('\n')
     if (/<[a-z][\s\S]*>/i.test(joined)) {
       return joined.replace(/<[^>]+>/g, '').replace(/&nbsp;/g, ' ').replace(/&amp;/g, '&').replace(/\s{3,}/g, '\n\n').trim()
     }
-
     return joined.trim()
   }
 
+  return null
+}
+
 function decodeEmailBody(text) {
   // Handle quoted-printable encoding (=XX hex sequences and soft line breaks)
   return text

server/routes/inbound-email.js

@@ -15,7 +15,7 @@ export function register(app) {
       res.status(401).json({ message: 'Unauthorized.' }); return
     }
 
-    const { from, to, subject, body, date, messageId, source } = req.body ?? {}
+    const { from, to, subject, body, htmlBody, date, messageId, source } = req.body ?? {}
 
     if (!from || typeof from !== 'string') {
       res.status(400).json({ message: 'Missing from address.' }); return
@@ -40,6 +40,7 @@ export function register(app) {
       name: fromName || fromEmail,
       email: fromEmail,
       message: [subject ? `Subject: ${subject}` : '', body ?? ''].filter(Boolean).join('\n\n'),
+      htmlBody: typeof htmlBody === 'string' && htmlBody.trim() ? htmlBody.trim() : null,
       messageType: 'general',
       subscribe: false,
       archived: false,

src/AdminPage.tsx

@@ -628,6 +628,7 @@ interface ContactSubmission {
   archived?: boolean
   source?: 'contact-form' | 'download' | 'inbound-email'
   inboundTo?: string
+  htmlBody?: string | null
 }
 
 interface ContactReplyDraft {
@@ -5051,7 +5052,20 @@ export default function AdminPage({ content, onSave, onLogout }: Props) {
                           </div>
 
                           <div className="admin-email-body">
-                            <p>{selected.message}</p>
+                            {selected.htmlBody ? (
+                              <iframe
+                                srcDoc={selected.htmlBody}
+                                sandbox="allow-same-origin"
+                                style={{ width: '100%', minHeight: '320px', border: 'none', background: '#fff', borderRadius: '4px' }}
+                                onLoad={e => {
+                                  const iframe = e.currentTarget
+                                  const h = iframe.contentDocument?.documentElement?.scrollHeight
+                                  if (h) iframe.style.height = `${h}px`
+                                }}
+                              />
+                            ) : (
+                              <p style={{ whiteSpace: 'pre-wrap' }}>{selected.message}</p>
+                            )}
                           </div>
 
                           <div className="admin-actions admin-actions--maintenance">