fix(mobile): exclude archived identities from mention autocomplete (#3840)

mobile/lib/features/channels/mentions/mention_candidates.dart

@@ -51,13 +51,20 @@ List<MentionCandidate> buildMentionCandidates({
   required Map<String, UserProfile> userCache,
   required Map<String, String> ownerByAgentPubkey,
   List<UserProfile> searchResults = const [],
+  Set<String> archivedPubkeys = const {},
   String? currentPubkey,
 }) {
   final candidates = <MentionCandidate>[];
   final seen = <String>{};
 
+  final self = currentPubkey?.toLowerCase();
   for (final member in members) {
     final pk = member.pubkey.toLowerCase();
+    // Fold relay-archived identities (#3840) out of
+    // autocomplete; the current user is exempt (NIP-IA §Self
+    // Requests anti-shadowban), matching desktop's
+    // `useIsArchivedPredicate`.
+    if (archivedPubkeys.contains(pk) && pk != self) continue;
     if (!seen.add(pk)) continue;
     final profile = userCache[pk];
     final ownerPubkey = ownerByAgentPubkey[pk] ?? profile?.ownerPubkey;

mobile/lib/features/channels/mentions/mention_candidates_provider.dart

@@ -80,6 +80,8 @@ final mentionCandidatesProvider = Provider.family
           ref.watch(agentDirectoryProvider).asData?.value ??
           const <AgentDirectoryEntry>[];
       final owners = ref.watch(agentOwnersProvider).asData?.value ?? const {};
+      final archived = ref.watch(archivedAgentPubkeysProvider).asData?.value ??
+          const <String>{};
       final channels =
           ref.watch(channelsProvider).asData?.value ?? const <Channel>[];
       final userCache = ref.watch(userCacheProvider);
@@ -100,6 +102,7 @@ final mentionCandidatesProvider = Provider.family
         userCache: userCache,
         ownerByAgentPubkey: owners,
         searchResults: searchResults,
+        archivedPubkeys: archived,
         currentPubkey: currentPubkey,
       );
 

mobile/lib/shared/mentions/agent_identity_provider.dart

@@ -69,6 +69,28 @@ final agentDirectoryProvider = FutureProvider<List<AgentDirectoryEntry>>((
   return [for (final event in events) AgentDirectoryEntry.fromEvent(event)];
 });
 
+/// NIP-IA archived-identity pubkeys (kind:13535 snapshot).
+///
+/// The relay emits a single relay-signed `p`-tag-per-identity snapshot listing
+/// identities archived on the relay. Mobile folds those identities out of
+/// mention autocomplete (desktop does the same via `useIsArchivedPredicate`).
+///
+/// Fail-open by construction: while the snapshot is missing or unfetched the
+/// set is empty, so a cold start or a relay without any archives never briefly
+/// hides everyone.
+final archivedAgentPubkeysProvider = FutureProvider<Set<String>>((ref) async {
+  final sessionState = ref.watch(relaySessionProvider);
+  if (sessionState.status != SessionStatus.connected) return const {};
+  final session = ref.read(relaySessionProvider.notifier);
+  final events = await session.fetchHistory(NostrFilters.archivedIdentities());
+  if (events.isEmpty) return const {};
+  return _AgentPubkeySet({
+    for (final tag in events.first.tags)
+      if (tag.length >= 2 && tag[0] == 'p') tag[1].toLowerCase(),
+  });
+});
+
+
 /// Verified NIP-OA owner pubkey per agent pubkey, from the agents' kind:0
 /// profiles. An entry exists only when the `auth` tag verifies — mirrors
 /// desktop's `profile_valid_oa_owner_pubkey`.

mobile/lib/shared/relay/nostr_filters.dart

@@ -209,6 +209,12 @@ abstract final class NostrFilters {
   static NostrFilter agentProfiles() =>
       const NostrFilter(kinds: [10100], limit: 100);
 
+  /// NIP-IA archived-identity list (kind:13535). Relay-signed addressable
+  /// snapshot; one `p` tag per archived identity. Addresses match the relay's
+  /// `KIND_IA_ARCHIVED_LIST` = 13535.
+  static NostrFilter archivedIdentities() =>
+      const NostrFilter(kinds: [13535], limit: 1);
+
   /// User status (NIP-38, kind:30315).
   static NostrFilter userStatus(String pubkey) =>
       NostrFilter(kinds: [30315], authors: [pubkey], limit: 1);

mobile/test/features/channels/mentions/mention_candidates_test.dart

@@ -280,5 +280,54 @@ void main() {
       expect(candidates, hasLength(1));
       expect(candidates.single.isMember, isTrue);
     });
+
+    test('archived agent identities are hidden from mention candidates', () {
+      final candidates = buildMentionCandidates(
+        members: [member(agentPubkey, role: 'bot')],
+        relayAgents: const [],
+        userCache: const {},
+        ownerByAgentPubkey: const {},
+        archivedPubkeys: {agentPubkey},
+        currentPubkey: userPubkey,
+      );
+
+      expect(candidates.any((c) => c.pubkey == agentPubkey), isFalse);
+    });
+
+    test('the current user is exempt from the archived fold', () {
+      final candidates = buildMentionCandidates(
+        members: [member(agentPubkey, role: 'bot')],
+        relayAgents: const [],
+        userCache: const {},
+        ownerByAgentPubkey: const {},
+        archivedPubkeys: {agentPubkey},
+        currentPubkey: agentPubkey,
+      );
+
+      expect(
+        candidates.any((c) => c.pubkey == agentPubkey),
+        isTrue,
+        reason: 'NIP-IA anti-shadowban: the archived self must remain visible',
+      );
+    });
+
+    test('a non-archived agent candidate remains when others are archived',
+        () {
+      const keptPubkey = 'b' * 64;
+      final candidates = buildMentionCandidates(
+        members: [
+          member(agentPubkey, role: 'bot'),
+          member(keptPubkey, role: 'bot'),
+        ],
+        relayAgents: const [],
+        userCache: const {},
+        ownerByAgentPubkey: const {},
+        archivedPubkeys: {agentPubkey},
+        currentPubkey: userPubkey,
+      );
+
+      expect(candidates.any((c) => c.pubkey == agentPubkey), isFalse);
+      expect(candidates.any((c) => c.pubkey == keptPubkey), isTrue);
+    });
   });
 }