import 'dart:async';
import 'package:connectivity_plus/connectivity_plus.dart';
import 'package:get/get.dart';

/// [ConnectionService] is a GetX Service that monitors internet connectivity status.
///
/// It utilizes the [Connectivity] class from the `connectivity_plus` package.
class ConnectionService extends GetxService {
  final Connectivity _connectivity = Connectivity();

  /// Subscription to the connectivity change stream.
  late StreamSubscription<List<ConnectivityResult>> _subscription;

  /// Reactive boolean to indicate the current internet connection status.
  /// `true` means the device is connected to the internet via Wi-Fi, mobile data, or other means.
  final RxBool isConnected = true.obs;

  bool get isCurrentlyConnected => isConnected.value;

  /// Called when the service is first initialized.
  @override
  void onInit() {
    super.onInit();
    _initConnectivity();
    _subscription = _connectivity.onConnectivityChanged.listen(_updateConnectionStatus);
  }

  /// Checks the initial connectivity status when the service is initialized.
  Future<void> _initConnectivity() async {
    try {
      final result = await _connectivity.checkConnectivity();
      _updateConnectionStatus(result); // Wrap in a list for consistency
    } catch (e) {
      isConnected.value = false;
    }
  }

  /// Callback function to handle changes in connectivity status.
  /// @param results A list of [ConnectivityResult] representing all active network connections.
  void _updateConnectionStatus(List<ConnectivityResult> results) {
    // If all results are `none`, the device is considered offline.
    isConnected.value = results.any((result) => result != ConnectivityResult.none);
  }

  Future<bool> checkConnection() async {
    final result = await _connectivity.checkConnectivity();
    return !result.contains(ConnectivityResult.none);
  }

  /// Cancels the connectivity subscription when the service is closed.
  @override
  void onClose() {
    _subscription.cancel();
    super.onClose();
  }
}