now method

@override Future<DateTime> now()

Fetches the current server time from the configured HTTP API.

Sends an HTTP GET request to the API endpoint defined by _api. If the response status code is not 200, throws an Exception describing the HTTP error.

The method expects the body to contain a date string in the format: "EEE, dd MMM yyyy HH:mm:ss 'GMT'". This string is parsed into a UTC DateTime and returned.

Throws an Exception if the HTTP request fails, times out, or the date parsing does not succeed.

Implementation

@override
Future<DateTime> now() async {
  final uri = Uri.parse(apiUrl ?? _api);
  final startTime = DateTime.now();

  final response = await http.get(uri).timeout(
    Duration(seconds: timeout),
    onTimeout: () {
      throw Exception('Timeout fetching time from API');
    },
  );

  final endTime = DateTime.now();

  if (response.statusCode != 200) {
    throw Exception(
      'Error ${response.statusCode}: failed to fetch time from API',
    );
  }

  try {
    DateTime serverDate;
    if (parseResponse != null) {
      serverDate = parseResponse!(response);
    } else {
      final String stringDate = response.body;
      final DateFormat format =
          DateFormat("EEE, dd MMM yyyy HH:mm:ss 'GMT'", 'en_US');
      serverDate = format.parse(stringDate, true);
    }

    final latency = endTime.difference(startTime);
    final correctedTime = serverDate.add(latency ~/ 2);

    return isUtc ? correctedTime.toUtc() : correctedTime;
  } catch (e) {
    throw Exception('Error parsing time from API: $e');
  }
}