decodeBbsSignature method
Decodes a Base64 URL-encoded BBS+ signature back into its original binary form.
The BBS+ signature string often includes a leading character (e.g., u
) for formatting purposes.
This function removes the leading character, normalizes the string as needed, and decodes it
back into a Uint8List representation of the BBS+ signature.
Implementation
Uint8List decodeBbsSignature(String bbsSignature) {
final base64Body = bbsSignature.substring(1); // remove leading "u"
final normalized =
base64Body.padRight((base64Body.length + 3) ~/ 4 * 4, '=');
return base64Url.decode(normalized);
}