yubioath-flutter/lib/oath/views/utils.dart
2023-02-24 14:19:34 +01:00

57 lines
1.8 KiB
Dart
Executable File

/*
* Copyright (C) 2022 Yubico.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import 'dart:math';
import '../../widgets/utf8_utils.dart';
import '../../core/models.dart';
import '../models.dart';
/// Calculates the available space for issuer and account name.
///
/// Returns a [Pair] of the space available for the issuer and account name,
/// respectively, based on the current state of the credential.
Pair<int, int> getRemainingKeySpace(
{required OathType oathType,
required int period,
required String issuer,
required String name}) {
int remaining = 64; // The field is 64 bytes in total.
if (oathType == OathType.totp && period != defaultPeriod) {
// Non-standard TOTP periods are stored as part of this data, as a "D/"- prefix.
remaining -= '$period/'.length;
}
int issuerSpace = byteLength(issuer);
if (issuer.isNotEmpty) {
// Issuer is separated from name with a ":", if present.
issuerSpace += 1;
}
return Pair(
// Always reserve at least one character for name
remaining - 1 - max(byteLength(name), 1),
remaining - issuerSpace,
);
}
/// Gets a textual name for the account, based on the issuer and name.
String getTextName(OathCredential credential) {
return credential.issuer != null
? '${credential.issuer} (${credential.name})'
: credential.name;
}