selfprivacy.org.app/lib/utils/password_generator.dart

118 lines
2.7 KiB
Dart

import 'dart:math';
Random _rnd = Random();
typedef StringGeneratorFunction = String Function();
class StringGenerators {
static const String letters = 'abcdefghijklmnopqrstuvwxyz';
static const String numbers = '1234567890';
static const String symbols = '_';
static String getRandomString(
final int length, {
final hasLowercaseLetters = false,
final hasUppercaseLetters = false,
final hasNumbers = false,
final hasSymbols = false,
final isStrict = false,
}) {
String chars = '';
if (hasLowercaseLetters) {
chars += letters;
}
if (hasUppercaseLetters) {
chars += letters.toUpperCase();
}
if (hasNumbers) {
chars += numbers;
}
if (hasSymbols) {
chars += symbols;
}
assert(chars.isNotEmpty, 'chart empty');
if (!isStrict) {
return genString(length, chars);
}
String res = '';
int loose = length;
if (hasLowercaseLetters) {
loose -= 1;
res += genString(1, letters);
}
if (hasUppercaseLetters) {
loose -= 1;
res += genString(1, letters.toUpperCase());
}
if (hasNumbers) {
loose -= 1;
res += genString(1, numbers.toUpperCase());
}
if (hasSymbols) {
loose -= 1;
res += genString(1, symbols);
}
res += genString(loose, chars);
final List<String> shuffledlist = res.split('')..shuffle();
return shuffledlist.join();
}
static String genString(final int length, final String chars) =>
String.fromCharCodes(
Iterable.generate(
length,
(final _) => chars.codeUnitAt(
_rnd.nextInt(chars.length),
),
),
);
static StringGeneratorFunction userPassword = () => getRandomString(
8,
hasLowercaseLetters: true,
hasUppercaseLetters: true,
hasNumbers: true,
isStrict: true,
);
static StringGeneratorFunction passwordSalt = () => getRandomString(
8,
hasLowercaseLetters: true,
);
static StringGeneratorFunction simpleId = () => getRandomString(
5,
hasLowercaseLetters: true,
);
static StringGeneratorFunction dbPassword = () => getRandomString(
40,
hasLowercaseLetters: true,
hasUppercaseLetters: true,
hasNumbers: true,
hasSymbols: true,
);
static StringGeneratorFunction dbStorageName = () => getRandomString(
6,
hasLowercaseLetters: true,
hasUppercaseLetters: false,
hasNumbers: true,
);
static StringGeneratorFunction apiToken = () => getRandomString(
64,
hasLowercaseLetters: true,
hasUppercaseLetters: true,
hasNumbers: true,
);
}