import 'dart:async';

import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';

import '../../../common/router/app_router.dart';
import 'auth_controller.dart';
import 'one_key_login_service.dart';

abstract final class LoginLauncher {
  static final OneKeyLoginService _service = OneKeyLoginService();
  static bool _starting = false;

  static Future<void> start(
    BuildContext context,
    WidgetRef ref, {
    String? next,
  }) async {
    if (_starting) return;
    _starting = true;

    var loadingVisible = false;

    void showLoading() {
      if (loadingVisible || !context.mounted) return;
      loadingVisible = true;
      unawaited(
        showDialog<void>(
          context: context,
          useRootNavigator: true,
          barrierDismissible: false,
          builder: (_) => const PopScope(
            canPop: false,
            child: Center(child: CircularProgressIndicator()),
          ),
        ),
      );
    }

    void dismissLoading() {
      if (!loadingVisible || !context.mounted) return;
      loadingVisible = false;
      Navigator.of(context, rootNavigator: true).pop();
    }

    try {
      final observer = _OneKeyLoginLifecycleObserver(_service);
      var observerAdded = false;
      late final OneKeyLoginOutcome outcome;
      try {
        WidgetsBinding.instance.addObserver(observer);
        observerAdded = true;
        // Carrier-auth initialization only begins after this explicit login
        // action. Keep the loading indicator visible while the native SDK
        // determines whether one-key login can be launched.
        showLoading();
        outcome = await _service.start(
          context: context,
          verifyToken: ref.read(authProvider.notifier).verifyOneKeyLogin,
          // The native carrier page follows the device, while linked H5 pages
          // retain the appearance selected inside the app.
          appIsDark: Theme.of(context).brightness == Brightness.dark,
          nativeIsDark:
              MediaQuery.platformBrightnessOf(context) == Brightness.dark,
          onNativeRequestDispatched: dismissLoading,
          onAuthPageOpened: dismissLoading,
        );
      } finally {
        dismissLoading();
        if (observerAdded) WidgetsBinding.instance.removeObserver(observer);
      }

      if (!context.mounted) return;
      switch (outcome) {
        case OneKeyLoginOutcome.success:
          if (next != null && next.isNotEmpty) GoRouter.of(context).go(next);
          return;
        case OneKeyLoginOutcome.cancelled:
        case OneKeyLoginOutcome.busy:
          return;
        case OneKeyLoginOutcome.fallback:
        case OneKeyLoginOutcome.unsupported:
          await openSmsLogin(context, next: next);
      }
    } finally {
      _starting = false;
    }
  }
}

Future<void> openSmsLogin(
  BuildContext context, {
  String? next,
  Future<void> Function()? onReturn,
}) async {
  if (!context.mounted) return;
  if (GoRouterState.of(context).matchedLocation == AppRoutes.login) return;
  final location = next == null || next.isEmpty
      ? AppRoutes.login
      : '${AppRoutes.login}?next=${Uri.encodeComponent(next)}';
  await GoRouter.of(context).push(location);
  if (context.mounted) await onReturn?.call();
}

class _OneKeyLoginLifecycleObserver with WidgetsBindingObserver {
  _OneKeyLoginLifecycleObserver(this.service);
  final OneKeyLoginService service;
  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) service.onAppResumed();
  }
}