around method

Implementation

Future<Page<T, C>?> around({K? key, C? cursor}) {
  if (_disposed) {
    return Future.value(null);
  }

  final bool locked = _guard.isLocked;

  return _guard.protect(() async {
    if ((locked && !isEmpty) || _disposed) {
      return null;
    }

    Log.debug('around(key: $key, cursor: $cursor)...', '$runtimeType');

    try {
      final Page<T, C>? page = await Backoff.run(
        () => provider.around(key, cursor, perPage),
        _cancelToken,
      );

      Log.debug(
        'around(key: $key, cursor: $cursor)... \n'
            '\tFetched ${page?.edges.length} items\n'
            '\tstartCursor: ${page?.info.startCursor}\n'
            '\tendCursor: ${page?.info.endCursor}\n'
            '\thasPrevious: ${page?.info.hasPrevious}\n'
            '\thasNext: ${page?.info.hasNext}',
        '$runtimeType',
      );

      for (var e in page?.edges ?? []) {
        items[onKey(e)] = e;
      }

      startCursor = page?.info.startCursor;
      endCursor = page?.info.endCursor;
      hasNext.value = page?.info.hasNext ?? hasNext.value;
      hasPrevious.value = page?.info.hasPrevious ?? hasPrevious.value;
      Log.debug('around(key: $key, cursor: $cursor)... done', '$runtimeType');

      return page;
    } catch (e) {
      if (e is! OperationCanceledException) {
        rethrow;
      }
    }

    return null;
  });
}