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,
          ),
        );
      },
      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 alreadyRegistered = false]) async {
    final clientState = ref.watch(ClientStateController.provider);
    if (clientState?.deviceId == null) ref.invalidateSelf();

    final capabilities = await ref
        .watch(ClientController.provider.notifier)
        .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,
  );
}