getLoginUsers method

Implementation

Future<List<DisplayUser>> getLoginUsers() async {
  const candidateRoutes = <String>[
    '/login/users',
    '/loginUsers',
    '/users/login',
  ];

  List<DisplayUser> parseUsers(http.Response res) {
    final raw = jsonDecode(res.body);
    final entries = (raw is Map) ? raw['users'] : null;
    if (entries is! List) return [];

    final users = <DisplayUser>[];
    for (final entry in entries) {
      if (entry is! Map) continue;
      final map = Map<String, dynamic>.from(entry);
      String? pick(List<String> keys) {
        for (final key in keys) {
          final v = map[key];
          if (v != null) {
            final s = v.toString().trim();
            if (s.isNotEmpty) return s;
          }
        }
        for (final kv in map.entries) {
          if (keys.any((k) => k.toLowerCase() == kv.key.toLowerCase())) {
            final s = kv.value?.toString().trim() ?? '';
            if (s.isNotEmpty) return s;
          }
        }
        return null;
      }

      final kzl = (pick(['KZL', 'kzl']) ?? '').trim();
      if (kzl.isEmpty || kzl == '??') continue;
      final user = DisplayUser(kzl);
      user.full_name = pick(['Vorname', 'vorname']);
      user.full_surname = pick(['Name', 'name']);
      users.add(user);
    }

    users.sort((a, b) {
      final aName = '${a.full_surname ?? ''} ${a.full_name ?? ''} ${a.name}'
          .toLowerCase();
      final bName = '${b.full_surname ?? ''} ${b.full_name ?? ''} ${b.name}'
          .toLowerCase();
      return aName.compareTo(bName);
    });
    return users;
  }

  http.Response? lastResponse;
  for (final route in candidateRoutes) {
    final res = (await postJSON(RequestData(route)))?.forceRes();
    lastResponse = res;
    debugPrint(
      'Remote.getLoginUsers route=$route status=${res?.statusCode} len=${res?.body.length ?? 0}',
    );
    if (res != null && (res.statusCode ~/ 100 == 2)) {
      final users = parseUsers(res);
      debugPrint('Remote.getLoginUsers parsed=${users.length} via $route');
      return users;
    }
    if (res?.statusCode == 404) {
      continue;
    }
    final preview = res?.body.substring(
          0,
          (res.body.length < 200) ? res.body.length : 200,
        ) ??
        '';
    debugPrint('Remote.getLoginUsers failed via $route: $preview');
    throw ResponseException(res);
  }

  debugPrint(
    'Remote.getLoginUsers failed: all candidate routes returned 404',
  );
  throw ResponseException(lastResponse);
}