refactor(profiles): remove dead registry surface

Delete unused registry members (ProfileConnectionRegistry.insertIfAbsent /
removeAllForProfile, ProfileRegistry.reorder, ProfilesView.countFor,
ConnectionRegistry.getDefault) and their orphan tests, refreshing the stale
docs that named removeAllForProfile as the profile-delete cleanup path.

Repair the "one default per profile" join-row invariant: the connectionId FK
cascade (foreign_keys=ON) silently drops a profile's default row while its
other rows survive, leaving it defaultless. Add promoteMissingDefaults, share
a deterministic re-promotion helper with remove(), and re-promote in
removeAllForConnection.

lib/connection/connection_registry.dart

@@ -1,7 +1,6 @@
 import 'dart:async';
 import 'dart:convert';
 
-import 'package:collection/collection.dart';
 import 'package:drift/drift.dart';
 
 import '../database/app_database.dart';
@@ -41,17 +40,6 @@ class ConnectionRegistry {
     return _rowToConnection(row);
   }
 
-  /// Returns the user's preferred connection — either the row marked
-  /// [Connections.isDefault], or the only row if exactly one exists, or
-  /// null when no connections are stored.
-  Future<Connection?> getDefault() async {
-    final rows = await _db.select(_db.connections).get();
-    if (rows.isEmpty) return null;
-    final flagged = rows.firstWhereOrNull((r) => r.isDefault);
-    final picked = flagged ?? (rows.length == 1 ? rows.single : null);
-    return picked == null ? null : _rowToConnection(picked);
-  }
-
   /// Insert or replace [connection]. If this is the first stored connection
   /// it is automatically marked default; re-upserting an existing row keeps
   /// the row's current `isDefault` (so token/metadata refreshes don't clear

lib/database/tables.dart

@@ -193,9 +193,9 @@ class ProfileConnections extends Table {
   // No FK on profile_id: Plex Home profiles are virtual (built by
   // Profile.virtualPlexHome from PlexHomeService's live cache, never
   // persisted in `profiles`), so an FK here would reject every join row
-  // they need. The two profile-delete sites clean up join rows manually
-  // via ProfileConnectionRegistry.removeAllForProfile before calling
-  // ProfileRegistry.remove.
+  // they need. Profile deletion instead cleans up join rows explicitly
+  // (removeAllProfileConnectionsAndCleanup in profile_connection_cleanup)
+  // before calling ProfileRegistry.remove.
   TextColumn get profileId => text()();
   TextColumn get connectionId => text().references(Connections, #id, onDelete: KeyAction.cascade)();
   TextColumn get userToken => text().withDefault(const Constant(''))();

lib/profiles/profile_connection_registry.dart

@@ -118,13 +118,6 @@ class ProfileConnectionRegistry {
     );
   }
 
-  /// Insert a new join row only if `(profileId, connectionId)` doesn't
-  /// already exist. Used by [ProfileSyncService] to surface new Plex Home
-  /// users without clobbering tokens cached by prior switches.
-  Future<void> insertIfAbsent(ProfileConnection pc) async {
-    await _db.into(_db.profileConnections).insert(await _companion(pc), mode: InsertMode.insertOrIgnore);
-  }
-
   /// Cache the freshly-acquired user token (e.g. after a `/home/users/switch`
   /// call). Updates `tokenAcquiredAt` to now.
   Future<void> recordToken(String profileId, String connectionId, String token) async {
@@ -149,12 +142,30 @@ class ProfileConnectionRegistry {
     await (_db.delete(
       _db.profileConnections,
     )..where((t) => t.profileId.equals(profileId) & t.connectionId.equals(connectionId))).go();
-    // If we just removed the default, promote the oldest remaining row.
-    final remaining = await (_db.select(_db.profileConnections)..where((t) => t.profileId.equals(profileId))).get();
-    if (remaining.isNotEmpty && !remaining.any((r) => r.isDefault)) {
-      await (_db.update(_db.profileConnections)
-            ..where((t) => t.profileId.equals(profileId) & t.connectionId.equals(remaining.first.connectionId)))
-          .write(const ProfileConnectionsCompanion(isDefault: Value(true)));
+    await _promoteDefaultIfMissing(profileId);
+  }
+
+  /// Re-promote a default for [profileId] when it has join rows but none is
+  /// flagged default — removing the default row would otherwise leave the
+  /// profile defaultless. Deterministic: picks the lowest connectionId,
+  /// matching [listForProfile]'s secondary ordering.
+  Future<void> _promoteDefaultIfMissing(String profileId) async {
+    final rows = await (_db.select(_db.profileConnections)..where((t) => t.profileId.equals(profileId))).get();
+    if (rows.isEmpty || rows.any((r) => r.isDefault)) return;
+    final pick = rows.map((r) => r.connectionId).reduce((a, b) => a.compareTo(b) <= 0 ? a : b);
+    await (_db.update(_db.profileConnections)
+          ..where((t) => t.profileId.equals(profileId) & t.connectionId.equals(pick)))
+        .write(const ProfileConnectionsCompanion(isDefault: Value(true)));
+  }
+
+  /// Repair the "exactly one default per profile" invariant across every
+  /// profile. The `connectionId` FK cascade (PRAGMA foreign_keys=ON) deletes
+  /// join rows silently when a Connection is removed, so a profile can be left
+  /// with surviving rows but no default flag.
+  Future<void> promoteMissingDefaults() async {
+    final profileIds = (await _db.select(_db.profileConnections).get()).map((r) => r.profileId).toSet();
+    for (final profileId in profileIds) {
+      await _promoteDefaultIfMissing(profileId);
     }
   }
 
@@ -172,16 +183,14 @@ class ProfileConnectionRegistry {
   }
 
   /// Remove every join row referencing [connectionId] (e.g. when a Connection
-  /// is deleted). Drift's referential integrity isn't enabled by default for
-  /// SQLite without `PRAGMA foreign_keys=ON`, so we cascade explicitly.
+  /// is deleted). The `connectionId` FK (PRAGMA foreign_keys=ON) already
+  /// cascades these rows away when the Connection row itself is deleted; this
+  /// stays the explicit path for callers that drop the rows first, and either
+  /// way repairs any profile the removal left without a default.
   Future<int> removeAllForConnection(String connectionId) async {
-    return await (_db.delete(_db.profileConnections)..where((t) => t.connectionId.equals(connectionId))).go();
-  }
-
-  /// Wipe every join row for [profileId] (e.g. when a Plex Home profile's
-  /// parent connection is removed).
-  Future<int> removeAllForProfile(String profileId) async {
-    return await (_db.delete(_db.profileConnections)..where((t) => t.profileId.equals(profileId))).go();
+    final removed = await (_db.delete(_db.profileConnections)..where((t) => t.connectionId.equals(connectionId))).go();
+    await promoteMissingDefaults();
+    return removed;
   }
 
   /// Wipe the entire join table. Used by sign-out so a fresh sign-in starts

lib/profiles/profile_registry.dart

@@ -73,16 +73,6 @@ class ProfileRegistry {
     return (_db.delete(_db.profiles)..where((t) => t.kind.equals(ProfileKind.plexHome.id))).go();
   }
 
-  Future<void> reorder(List<String> idsInOrder) async {
-    await _db.transaction(() async {
-      for (var i = 0; i < idsInOrder.length; i++) {
-        await (_db.update(
-          _db.profiles,
-        )..where((t) => t.id.equals(idsInOrder[i]))).write(ProfilesCompanion(sortOrder: Value(i)));
-      }
-    });
-  }
-
   Future<void> clear() async {
     await _db.delete(_db.profiles).go();
   }

lib/profiles/profiles_view.dart

@@ -28,11 +28,6 @@ class ProfilesView {
   const ProfilesView({required this.profiles, required this.connectionsByProfile, required this.connectionsById});
 
   static const empty = ProfilesView(profiles: [], connectionsByProfile: {}, connectionsById: {});
-
-  int countFor(Profile profile) {
-    if (profile.isPlexHome) return profile.parentConnectionId == null ? 0 : 1;
-    return connectionsByProfile[profile.id]?.length ?? 0;
-  }
 }
 
 /// Join-table rows that should be shown as explicit, user-manageable

test/connection/connection_registry_test.dart

@@ -11,6 +11,15 @@ import 'package:plezy/services/plex_auth_service.dart';
 
 import '../test_helpers/prefs.dart';
 
+/// The id of the connection currently flagged default, read straight from the
+/// row (the registry maintains the flag; there is no public reader).
+Future<String?> _defaultConnectionId(AppDatabase db) async {
+  for (final row in await db.select(db.connections).get()) {
+    if (row.isDefault) return row.id;
+  }
+  return null;
+}
+
 JellyfinConnection _jellyfin({String id = 'srv-1', String userName = 'edde'}) {
   return JellyfinConnection(
     id: id,
@@ -71,7 +80,7 @@ void main() {
   group('ConnectionRegistry', () {
     test('list() returns empty when no connections stored', () async {
       expect(await registry.list(), isEmpty);
-      expect(await registry.getDefault(), isNull);
+      expect(await _defaultConnectionId(db), isNull);
     });
 
     test('first upserted connection becomes the default', () async {
@@ -80,8 +89,7 @@ void main() {
       expect(list.length, 1);
       expect(list.first.id, 'a');
 
-      final defaultConn = await registry.getDefault();
-      expect(defaultConn?.id, 'a');
+      expect(await _defaultConnectionId(db), 'a');
     });
 
     test('upsert preserves type discriminator (Plex vs Jellyfin)', () async {
@@ -141,10 +149,10 @@ void main() {
       await registry.upsert(_jellyfin(id: 'b'));
       // First is default by default; explicitly switch to b.
       await registry.setDefault('b');
-      expect((await registry.getDefault())?.id, 'b');
+      expect(await _defaultConnectionId(db), 'b');
       // Switch back to a.
       await registry.setDefault('a');
-      expect((await registry.getDefault())?.id, 'a');
+      expect(await _defaultConnectionId(db), 'a');
     });
 
     test('remove deletes a row and re-elects a default when needed', () async {
@@ -153,10 +161,10 @@ void main() {
       // a is default (first one in).
       await registry.remove('a');
       // b should now be the default.
-      expect((await registry.getDefault())?.id, 'b');
+      expect(await _defaultConnectionId(db), 'b');
       // Removing the last clears the default cleanly.
       await registry.remove('b');
-      expect(await registry.getDefault(), isNull);
+      expect(await _defaultConnectionId(db), isNull);
     });
 
     test('re-upsert preserves the existing default flag', () async {
@@ -165,15 +173,15 @@ void main() {
       // wrote `isFirst` (false on update).
       await registry.upsert(_jellyfin(id: 'a'));
       await registry.upsert(_jellyfin(id: 'b'));
-      expect((await registry.getDefault())?.id, 'a');
+      expect(await _defaultConnectionId(db), 'a');
 
       // Re-upsert the default with refreshed credentials.
       await registry.upsert(_jellyfin(id: 'a', userName: 'refreshed'));
-      expect((await registry.getDefault())?.id, 'a');
+      expect(await _defaultConnectionId(db), 'a');
 
       // And re-upserting a non-default row doesn't accidentally promote it.
       await registry.upsert(_jellyfin(id: 'b', userName: 'refreshed'));
-      expect((await registry.getDefault())?.id, 'a');
+      expect(await _defaultConnectionId(db), 'a');
     });
 
     test('recordAuthSuccess updates lastAuthenticatedAt without losing config', () async {

test/database/app_database_test.dart

@@ -58,10 +58,10 @@ class _AppDatabaseTestSuite {
 
       test('ProfileConnections has no profile_id FK (virtual plex_home profiles)', () async {
         // v20 dropped the profile_id FK so virtual Plex Home profiles can
-        // persist join rows without a parent `profiles` row. The two
-        // profile-delete sites (profile_detail_screen, profile_switch_screen)
-        // call ProfileConnectionRegistry.removeAllForProfile manually before
-        // deleting the profile, so the cascade isn't needed.
+        // persist join rows without a parent `profiles` row. Profile deletion
+        // instead cleans up join rows explicitly (via the teardown flow's
+        // removeAllProfileConnectionsAndCleanup) before deleting the profile,
+        // so the cascade isn't needed.
         final now = DateTime.now().millisecondsSinceEpoch;
         await db
             .into(db.connections)

test/profiles/profile_connection_registry_test.dart

@@ -144,16 +144,40 @@ void main() {
       expect(await registry.listForConnection('c1'), isEmpty);
     });
 
-    test('removeAllForProfile drops every row for a profile', () async {
+    test('removeAllForConnection re-promotes a default for a surviving profile', () async {
       await registry.upsert(
         const ProfileConnection(profileId: 'p1', connectionId: 'c1', userToken: 't', userIdentifier: 'u'),
+        makeDefault: true,
       );
       await registry.upsert(
         const ProfileConnection(profileId: 'p1', connectionId: 'c2', userToken: 't', userIdentifier: 'u'),
       );
-      final removed = await registry.removeAllForProfile('p1');
-      expect(removed, 2);
-      expect(await registry.listForProfile('p1'), isEmpty);
+      // c1 is default; removing it connection-wide must leave p1 with c2 as
+      // its new default rather than defaultless.
+      await registry.removeAllForConnection('c1');
+      final remaining = await registry.listForProfile('p1');
+      expect(remaining, hasLength(1));
+      expect(remaining.single.connectionId, 'c2');
+      expect(remaining.single.isDefault, isTrue);
+    });
+
+    test('promoteMissingDefaults repairs a profile the FK cascade left defaultless', () async {
+      await registry.upsert(
+        const ProfileConnection(profileId: 'p1', connectionId: 'c1', userToken: 't', userIdentifier: 'u'),
+        makeDefault: true,
+      );
+      await registry.upsert(
+        const ProfileConnection(profileId: 'p1', connectionId: 'c2', userToken: 't', userIdentifier: 'u'),
+      );
+      // Deleting the connection cascades away p1's default join row (c1) via
+      // the connectionId FK, silently leaving p1 with no default flag.
+      await (db.delete(db.connections)..where((t) => t.id.equals('c1'))).go();
+      final beforeRepair = await registry.listForProfile('p1');
+      expect(beforeRepair.single.connectionId, 'c2');
+      expect(beforeRepair.single.isDefault, isFalse);
+
+      await registry.promoteMissingDefaults();
+      expect((await registry.listForProfile('p1')).single.isDefault, isTrue);
     });
 
     test('upsert succeeds for a virtual plex_home profile id with no parent row', () async {