From 433a63bf1a569478cbb781cbf16069b5d28a79f2 Mon Sep 17 00:00:00 2001
From: Linus Rath <139418639+rathlinus@users.noreply.github.com>
Date: Wed, 20 May 2026 18:42:12 +0200
Subject: [PATCH] fix: normalize malformed contact photo data URIs #307

---
 components/contacts/contact-form.tsx   |  5 ++-
 stores/__tests__/contact-store.test.ts | 42 +++++++++++++++++++++++++-
 stores/contact-store.ts                | 19 +++++++++++-
 3 files changed, 63 insertions(+), 3 deletions(-)

diff --git a/components/contacts/contact-form.tsx b/components/contacts/contact-form.tsx
index 5fa6c363..c99491fa 100644
--- a/components/contacts/contact-form.tsx
+++ b/components/contacts/contact-form.tsx
@@ -6,6 +6,7 @@ import { X, Plus, ChevronDown, ChevronRight, User, Building, MapPin, Globe, Cake
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Avatar } from "@/components/ui/avatar";
+import { normalizeContactPhotoUri } from "@/stores/contact-store";
 import { cn } from "@/lib/utils";
 import type { ContactCard, ContactOnlineService, ContactAnniversary, ContactPersonalInfo, AddressBook, AnniversaryDate, PartialDate, ContactAddress, ContactMedia } from "@/lib/jmap/types";
 
@@ -341,7 +342,9 @@ export function ContactForm({ contact, addressBooks, allKeywords, defaultAddress
   const initialPhotoEntry = useMemo(() => {
     if (!contact?.media) return null;
     for (const [key, m] of Object.entries(contact.media)) {
-      if (m.kind === "photo" && m.uri) return { key, uri: m.uri, mediaType: m.mediaType };
+      if (m.kind === "photo" && m.uri) {
+        return { key, uri: normalizeContactPhotoUri(m.uri, m.mediaType), mediaType: m.mediaType };
+      }
     }
     return null;
   }, [contact]);
diff --git a/stores/__tests__/contact-store.test.ts b/stores/__tests__/contact-store.test.ts
index 093e40d3..dd9dbec7 100644
--- a/stores/__tests__/contact-store.test.ts
+++ b/stores/__tests__/contact-store.test.ts
@@ -1,5 +1,5 @@
 import { describe, it, expect, beforeEach, vi } from 'vitest';
-import { useContactStore } from '../contact-store';
+import { useContactStore, getContactPhotoUri, normalizeContactPhotoUri } from '../contact-store';
 import type { ContactCard } from '@/lib/jmap/types';
 
 vi.stubGlobal('crypto', { randomUUID: () => '00000000-0000-0000-0000-000000000000' });
@@ -496,6 +496,46 @@ describe('contact-store', () => {
     });
   });
 
+  describe('normalizeContactPhotoUri', () => {
+    it('rewrites malformed data:base64,... URIs using the media mediaType', () => {
+      expect(normalizeContactPhotoUri('data:base64,AAAA', 'image/png'))
+        .toBe('data:image/png;base64,AAAA');
+    });
+
+    it('rewrites data:;base64,... URIs using the media mediaType', () => {
+      expect(normalizeContactPhotoUri('data:;base64,AAAA', 'image/gif'))
+        .toBe('data:image/gif;base64,AAAA');
+    });
+
+    it('defaults to image/jpeg when no mediaType is available', () => {
+      expect(normalizeContactPhotoUri('data:base64,AAAA'))
+        .toBe('data:image/jpeg;base64,AAAA');
+    });
+
+    it('leaves well-formed data URIs unchanged', () => {
+      const good = 'data:image/png;base64,AAAA';
+      expect(normalizeContactPhotoUri(good)).toBe(good);
+    });
+
+    it('leaves http(s) URIs unchanged', () => {
+      const url = 'https://example.com/photo.jpg';
+      expect(normalizeContactPhotoUri(url)).toBe(url);
+    });
+  });
+
+  describe('getContactPhotoUri', () => {
+    it('returns a normalized data URI for malformed Stalwart photos (#307)', () => {
+      const contact = makeContact({
+        media: { m0: { kind: 'photo', uri: 'data:base64,AAAA', mediaType: 'image/png' } },
+      });
+      expect(getContactPhotoUri(contact)).toBe('data:image/png;base64,AAAA');
+    });
+
+    it('returns undefined when no photo media is present', () => {
+      expect(getContactPhotoUri(makeContact())).toBeUndefined();
+    });
+  });
+
   describe('persistence/partialize', () => {
     it('should persist contacts when supportsSync is false', () => {
       const { partialize } = (useContactStore as unknown as { persist: { getOptions: () => { partialize: (state: Record<string, unknown>) => Record<string, unknown> } } }).persist.getOptions();
diff --git a/stores/contact-store.ts b/stores/contact-store.ts
index a376ed7a..df33ddd9 100644
--- a/stores/contact-store.ts
+++ b/stores/contact-store.ts
@@ -37,10 +37,27 @@ export function getContactPrimaryEmail(contact: ContactCard): string {
   return Object.values(contact.emails)[0]?.address || '';
 }
 
+// Some JMAP servers (notably Stalwart, see issue #307) emit photo data URIs
+// without a mediatype, like `data:base64,...` or `data:;base64,...`. Per
+// RFC 2397 the missing/empty mediatype defaults to `text/plain`, so browsers
+// won't render the bytes as an image. Rewrite to include a mediatype.
+export function normalizeContactPhotoUri(uri: string, mediaType?: string): string {
+  const mime = mediaType && mediaType.includes('/') ? mediaType : 'image/jpeg';
+  if (uri.startsWith('data:base64,')) {
+    return `data:${mime};base64,${uri.slice('data:base64,'.length)}`;
+  }
+  if (uri.startsWith('data:;base64,')) {
+    return `data:${mime};base64,${uri.slice('data:;base64,'.length)}`;
+  }
+  return uri;
+}
+
 export function getContactPhotoUri(contact: ContactCard): string | undefined {
   if (!contact.media) return undefined;
   for (const media of Object.values(contact.media)) {
-    if (media.kind === 'photo' && media.uri) return media.uri;
+    if (media.kind === 'photo' && media.uri) {
+      return normalizeContactPhotoUri(media.uri, media.mediaType);
+    }
   }
   return undefined;
 }