generateUuid function
Generate a v4 UUID.
Implementation
String generateUuid() {
final bytes = List<int>.generate(16, (_) => _secureRandom.nextInt(256));
// Set version to 4
bytes[6] = (bytes[6] & 0x0f) | 0x40;
// Set variant to RFC 4122
bytes[8] = (bytes[8] & 0x3f) | 0x80;
final hex = bytes.map((b) => b.toRadixString(16).padLeft(2, '0')).join();
return '${hex.substring(0, 8)}-'
'${hex.substring(8, 12)}-'
'${hex.substring(12, 16)}-'
'${hex.substring(16, 20)}-'
'${hex.substring(20, 32)}';
}