feat(templates): add support for HTML templates

components/email/email-composer.tsx

@@ -1092,7 +1092,7 @@ export function EmailComposer({
       : template.body;
 
     // In plain text mode, use template body as-is; otherwise convert to HTML
-    const bodyContent = plainTextMode
+    const bodyContent = plainTextMode || template.isHTML
       ? filledBody
       : `<p>${filledBody.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>')}</p>`;
 

components/templates/placeholder-fill-modal.tsx

@@ -94,7 +94,7 @@ export function PlaceholderFillModal({
             <div className="mt-4 pt-4 border-t border-border">
               <p className="text-xs font-medium text-muted-foreground mb-2">{t('preview')}</p>
               <div className="text-sm text-foreground whitespace-pre-wrap p-3 rounded-md bg-muted/50 border border-border max-h-32 overflow-y-auto">
-                {preview}
+                {template.isHTML ? <div dangerouslySetInnerHTML={{ __html: preview }}></div> : preview}
               </div>
             </div>
           )}

components/templates/template-form.tsx

@@ -4,7 +4,7 @@ import { useState, useMemo } from 'react';
 import { useTranslations } from 'next-intl';
 import { Button } from '@/components/ui/button';
 import { Input } from '@/components/ui/input';
-import { Star, Plus } from 'lucide-react';
+import { Star, Plus, Square, CheckSquare } from 'lucide-react';
 import { cn } from '@/lib/utils';
 import { validateTemplateName } from '@/lib/template-utils';
 import { BUILT_IN_PLACEHOLDERS } from '@/lib/template-types';
@@ -38,6 +38,7 @@ export function TemplateForm({ template, initialData, onSave, onCancel }: Templa
   const [category, setCategory] = useState(template?.category || '');
   const [subject, setSubject] = useState(template?.subject || initialData?.subject || '');
   const [body, setBody] = useState(template?.body || initialData?.body || '');
+  const [isHTML, setIsHTML] = useState(template?.isHTML || false);
   const [toRecipients, setToRecipients] = useState(
     template?.defaultRecipients?.to?.join(', ') || initialData?.to?.join(', ') || ''
   );
@@ -76,6 +77,7 @@ export function TemplateForm({ template, initialData, onSave, onCancel }: Templa
       name: name.trim(),
       subject,
       body,
+      isHTML,
       category: category.trim(),
       defaultRecipients: to.length || cc.length || bcc.length
         ? { to: to.length ? to : undefined, cc: cc.length ? cc : undefined, bcc: bcc.length ? bcc : undefined }
@@ -190,6 +192,14 @@ export function TemplateForm({ template, initialData, onSave, onCancel }: Templa
           rows={6}
           className="mt-1 w-full rounded-md border border-border bg-background px-3 py-2 text-sm text-foreground placeholder:text-muted-foreground focus:outline-none focus:ring-2 focus:ring-primary resize-y"
         />
+        <button
+          type="button"
+          onClick={() => setIsHTML(!isHTML)}
+          className="flex items-center gap-1.5 text-sm text-muted-foreground hover:text-foreground transition-colors"
+        >
+          {isHTML ? <CheckSquare className={cn('w-4 h-4')}></CheckSquare> : <Square className={cn('w-4 h-4')}></Square>}
+          HTML
+        </button>
       </div>
 
       <div className="grid grid-cols-1 sm:grid-cols-3 gap-3">

lib/__tests__/template-utils.test.ts

@@ -20,6 +20,7 @@ function makeTemplate(overrides: Partial<EmailTemplate> = {}): EmailTemplate {
     name: 'Test Template',
     subject: '',
     body: '',
+    isHTML: false,
     category: '',
     isFavorite: false,
     createdAt: '2026-01-01T00:00:00Z',

lib/template-types.ts

@@ -3,6 +3,7 @@ export interface EmailTemplate {
   name: string;
   subject: string;
   body: string;
+  isHTML?: boolean;
   category: string;
   defaultRecipients?: {
     to?: string[];

lib/template-utils.ts

@@ -173,7 +173,8 @@ export function importTemplates(json: string): ImportResult {
       id: generateUUID(),
       name: sanitizeText(t.name),
       subject: sanitizeText(t.subject),
-      body: sanitizeText(t.body),
+      body: t.isHTML ? String(t.body || '') : sanitizeText(t.body),
+      isHTML: Boolean(t.isHTML),
       category: sanitizeText(t.category),
       defaultRecipients: recipients && typeof recipients === 'object'
         ? {