support for registering pushers

lib/controllers/client.dart

@@ -2,6 +2,7 @@ import "dart:ffi";
 import "dart:io";
 import "dart:isolate";
 import "dart:math";
+
 import "package:fast_immutable_collections/fast_immutable_collections.dart";
 import "package:ffi/ffi.dart";
 import "package:flutter/foundation.dart";
@@ -14,6 +15,7 @@ import "package:nexus/controllers/sync_status.dart";
 import "package:nexus/controllers/top_level_spaces.dart";
 import "package:nexus/helpers/extensions/gomuks_buffer.dart";
 import "package:nexus/main.dart";
+import "package:nexus/models/capabilities.dart";
 import "package:nexus/models/content/message.dart";
 import "package:nexus/models/event.dart";
 import "package:nexus/models/oauth_auth_code_response.dart";
@@ -30,6 +32,7 @@ import "package:nexus/models/requests/oauth/get_auth_url.dart";
 import "package:nexus/models/requests/oauth/register_client.dart";
 import "package:nexus/models/requests/paginate.dart";
 import "package:nexus/models/requests/redact_event.dart";
+import "package:nexus/models/requests/register_pusher.dart";
 import "package:nexus/models/requests/report.dart";
 import "package:nexus/models/requests/send_event.dart";
 import "package:nexus/models/requests/send_message.dart";
@@ -273,6 +276,9 @@ class ClientController extends AsyncNotifier<int> {
   Future<void> setAccountData(SetAccountDataRequest request) =>
       _sendCommand("set_account_data", request.toJson());
 
+  Future<void> registerPusher(RegisterPusherRequest request) =>
+      _sendCommand("register_homeserver_push", request.toJson());
+
   Future<MessageContent> uploadMedia(UploadMediaRequest request) async =>
       .fromJson(await _sendCommand("upload_media", request.toJson()));
 
@@ -310,6 +316,10 @@ class ClientController extends AsyncNotifier<int> {
   Future<SpecVersionsResponse> getSpecVersions() async =>
       .fromJson(await _sendCommand("get_versions"));
 
+  Future<Capabilities> getCapabilities() async => Capabilities.fromJson(
+    (await _sendCommand("get_capabilities"))["capabilities"],
+  );
+
   Future<Uri?> discoverHomeserver(Uri homeserver) async {
     try {
       final response = await _sendCommand("discover_homeserver", {

lib/controllers/settings_sections.dart

@@ -9,6 +9,7 @@ import "package:nexus/controllers/account_data.dart";
 import "package:nexus/controllers/client.dart";
 import "package:nexus/controllers/client_state.dart";
 import "package:nexus/controllers/settings.dart";
+import "package:nexus/controllers/unified_push.dart";
 import "package:nexus/controllers/spec_versions.dart";
 import "package:nexus/models/account_data.dart";
 import "package:nexus/models/settings_category.dart";
@@ -95,6 +96,46 @@ class SettingsSectionsController
       if (ref.watch(ClientStateController.provider)?.isLoggedIn == true)
         "Account": .new([
           .new(title: "Profile", icon: Icons.person, settings: .new([])),
+          .new(
+            title: "Notifications",
+            icon: Icons.notifications,
+            settings: .new([
+              // TODO: Disable if not supported
+              .new(
+                title: "Push notifications",
+                description: "Enable push notifications using Web Push",
+                builder: (title, description, icon) => Consumer(
+                  builder: (context, ref, _) {
+                    final pusherRegistered = ref.watch(
+                      UnifiedPushController.provider,
+                    );
+                    return SwitchListTile(
+                      title: Text(title),
+                      subtitle: Text(description),
+                      secondary: Icon(icon),
+                      value: pusherRegistered.maybeWhen(
+                        data: (value) => value,
+                        orElse: () => false,
+                      ),
+                      onChanged: pusherRegistered.maybeWhen(
+                        data: (_) =>
+                            (value) => value
+                            ? ref
+                                  .watch(
+                                    UnifiedPushController.provider.notifier,
+                                  )
+                                  .register()
+                                  .onError(showError)
+                            : /*deregeister*/ null,
+                        orElse: () => null,
+                      ),
+                    );
+                  },
+                ),
+                icon: Icons.notification_add,
+              ),
+            ]),
+          ),
           .new(
             title: "Safety",
             icon: Icons.gpp_good,
@@ -166,6 +207,8 @@ class SettingsSectionsController
                       onPressed: () async {
                         Navigator.of(context)
                             .popUntil((route) => route.isFirst);
+                        Navigator.of(context)
+                            .popUntil((route) => route.isFirst);
 
                         await WidgetsBinding.instance.endOfFrame;
 

lib/controllers/unified_push.dart

@@ -0,0 +1,106 @@
+import "dart:io";
+
+import "package:flutter_riverpod/flutter_riverpod.dart";
+import "package:intl/intl.dart";
+import "package:nexus/main.dart";
+import "package:nexus/controllers/client.dart";
+import "package:nexus/controllers/client_state.dart";
+import "package:nexus/models/requests/register_pusher.dart";
+import "package:unifiedpush/unifiedpush.dart";
+import "package:unifiedpush_storage_shared_preferences/storage.dart";
+
+class UnifiedPushController extends AsyncNotifier<bool> {
+  @override
+  Future<bool> build() async {
+    final registered = await UnifiedPush.initialize(
+      linuxOptions: .new(
+        dbusName: "nexus.federated.nexus",
+        storage: UnifiedPushStorageSharedPreferences(),
+        background: isInBackground,
+      ),
+      onNewEndpoint: (endpoint, instance) async {
+        final client = ref.watch(ClientController.provider.notifier);
+        await client.registerPusher(
+          .new(
+            appDisplayName: "Nexus",
+            appId: "nexus.federated.nexus",
+            data: PusherData.webPush(
+              url: Uri.parse(endpoint.url),
+              auth: endpoint.pubKeySet!.auth,
+            ),
+            deviceDisplayName:
+                "Nexus on ${toBeginningOfSentenceCase(Platform.operatingSystem)}",
+            kind: .webPush,
+            lang: "en",
+            pushKey: endpoint.pubKeySet!.pubKey,
+          ),
+
+          // Pusher(
+          //   appDisplayName: ,
+          //   data: {
+          //     "url": endpoint.url,
+          //     "auth": endpoint.pubKeySet.auth,
+          //     "format": "event_id_only",
+          //   },
+          //   deviceDisplayName: "Nexus",
+          //   kind: "org.matrix.msc4174.webpush",
+          //   lang: WidgetsBinding.instance.platformDispatcher.locale
+          //       .toLanguageTag(),
+          //   pushkey: endpoint.pubKeySet.publicKey,
+          // ),
+        );
+      },
+      onMessage: (message, instance) async {
+        print(message);
+        // TODO: Handle incoming message
+      },
+      onRegistrationFailed: (e, r) {
+        throw "e";
+      },
+      onUnregistered: (_) {
+        throw "r";
+      },
+      onTempUnavailable: (_) {
+        throw "t";
+      },
+    );
+
+    if (registered) {
+      // Needs to be registered every startup
+      await register(true);
+    }
+
+    return registered;
+  }
+
+  Future<void> register([bool early = false]) async {
+    final clientState = ref.watch(ClientStateController.provider);
+    if (clientState?.deviceId == null) ref.invalidateSelf();
+
+    final alreadyRegistered = early ? true : await future;
+    final client = ref.watch(ClientController.provider.notifier);
+    final capabilities = await client.getCapabilities();
+
+    if (capabilities.webpush?.vapid == null) {
+      throw UnsupportedError(
+        "Your homeserver does not support MSC4174 (Web Push), and therefore cannot send notifications to Nexus.",
+      );
+    }
+
+    if (!alreadyRegistered &&
+        !await UnifiedPush.tryUseCurrentOrDefaultDistributor()) {
+      throw Exception("No UnifiedPush distributors found");
+    }
+
+    await UnifiedPush.register(
+      instance: clientState!.deviceId!,
+      vapid: capabilities.webpush?.vapid,
+    );
+
+    if (!alreadyRegistered) ref.invalidateSelf();
+  }
+
+  static final provider = AsyncNotifierProvider<UnifiedPushController, bool>(
+    UnifiedPushController.new,
+  );
+}