import 'dart:async';

import 'package:esp_smartconfig/esp_smartconfig.dart';

import '../models/wiz_provisioning_device.dart';

abstract class WizSmartPairingService {
  Stream<WizProvisioningDevice> startProvisioning({
    required String ssid,
    required String password,
    String? bssid,
  });

  Future<void> stopProvisioning();
}

class EspTouchWizSmartPairingService implements WizSmartPairingService {
  Provisioner? _provisioner;
  StreamSubscription<ProvisioningResponse>? _subscription;
  StreamController<WizProvisioningDevice>? _controller;

  @override
  Stream<WizProvisioningDevice> startProvisioning({
    required String ssid,
    required String password,
    String? bssid,
  }) {
    if (_provisioner != null || _controller != null) {
      throw StateError('Provisioning is already running');
    }

    final provisioner = Provisioner.espTouch();
    final controller = StreamController<WizProvisioningDevice>.broadcast();
    _provisioner = provisioner;
    _controller = controller;

    _subscription = provisioner.listen(
      (response) {
        controller.add(
          WizProvisioningDevice(
            bssid: response.bssidText,
            ipAddress: response.ipAddressText,
          ),
        );
      },
      onError: controller.addError,
      onDone: () async {
        if (!controller.isClosed) {
          await controller.close();
        }
      },
    );

    final request = ProvisioningRequest.fromStrings(
      ssid: ssid,
      bssid: (bssid == null || bssid.trim().isEmpty)
          ? '00:00:00:00:00:00'
          : bssid.trim(),
      password: password.isEmpty ? null : password,
    );

    unawaited(
      provisioner.start(request).catchError((
        Object error,
        StackTrace stack,
      ) async {
        if (!controller.isClosed) {
          controller.addError(error, stack);
          await controller.close();
        }
      }),
    );

    return controller.stream;
  }

  @override
  Future<void> stopProvisioning() async {
    final provisioner = _provisioner;
    _provisioner = null;

    try {
      provisioner?.stop();
    } finally {
      await _subscription?.cancel();
      _subscription = null;
      if (_controller != null && !_controller!.isClosed) {
        await _controller!.close();
      }
      _controller = null;
    }
  }
}