import 'dart:async';

import 'package:desktopapp/classes/stream_element.dart';
import 'package:desktopapp/utils/logger.dart';
import 'package:enough_mail/enough_mail.dart';

class Mailer {
  static MailClient? _mailClient;

  /// High level mail API example
  static Future<bool> connect({
    required String email,
    required String password,
    required StreamController<StreamElement> streamController,
  }) async {
    Logger.log(LoggerType.info, Mailer, 'Discovering settings for $email');
    final config = await Discover.discover(email);
    if (config == null) {
      Logger.log(LoggerType.info, Mailer,
          'Unable to autodiscover settings for $email');
      return false;
    }
    Logger.log(LoggerType.info, Mailer, 'Settings for $email : $config');
    final account = MailAccount.fromDiscoveredSettings(
        'my account', email, password, config);
    _mailClient = MailClient(account, isLogEnabled: true);
    try {
      await _mailClient!.connect();
      Logger.log(LoggerType.info, Mailer, 'Connected to $email');
      streamController
          .add(StreamElement(StreamElementType.log, 'Connected to $email'));
      await _mailClient!.selectInbox();
      streamController.add(
          StreamElement(StreamElementType.log, 'INBOX selected for $email'));
      _mailClient!.eventBus.on<ImapEvent>().listen((ImapEvent event) async {
        if (event.eventType == ImapEventType.exists) {
          final evt = event as ImapMessagesExistEvent;
          if (evt.newMessagesExists <= evt.oldMessagesExists) return;
          final sequence = MessageSequence();
          if (evt.newMessagesExists - evt.oldMessagesExists > 1) {
            sequence.addRange(evt.oldMessagesExists, evt.newMessagesExists);
          } else {
            sequence.add(evt.newMessagesExists);
          }
          final messages = await _mailClient!.fetchMessageSequence(sequence,
              fetchPreference: FetchPreference.envelope);
          for (final message in messages) {
            var mailEvt = MailLoadEvent(message, _mailClient!);
            streamController.add(StreamElement(StreamElementType.alert,
                mailEvt.message.decodeSubject() ?? ''));
            // var content = mailEvt.message.decodeSubject();
            // var mess = mailEvt.message.decodeTextPlainPart();

            // Logger.log(LoggerType.info, Mailer, 'New message $content : $mess');
            // Requests.sendAlert('*$content* $mess');
          }
        }
      });
      await _mailClient!.startPolling();
      return true;
    } on MailException catch (e) {
      streamController.add(StreamElement(StreamElementType.log, e.toString()));
      Logger.log(LoggerType.error, Mailer, 'High level API failed with $e');
      return false;
    }
  }

  static Future<void> disconnect() async {
    if (_mailClient == null) return;
    Logger.log(LoggerType.info, Mailer, 'Disconnecting from mail');
    await _mailClient!.stopPolling();
    await _mailClient!.disconnect();
    Logger.log(LoggerType.info, Mailer, 'Disconnected from mail');
    _mailClient = null;
  }
}