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import { sshash } from './sshash.ts';
export function checkAddressChecksum (decoded: Uint8Array): [boolean, number, number, number] {  const ss58Length = (decoded[0] & 0b0100_0000) ? 2 : 1;  const ss58Decoded = ss58Length === 1    ? decoded[0]    : ((decoded[0] & 0b0011_1111) << 2) | (decoded[1] >> 6) | ((decoded[1] & 0b0011_1111) << 8);
  // 32/33 bytes public + 2 bytes checksum + prefix  const isPublicKey = [34 + ss58Length, 35 + ss58Length].includes(decoded.length);  const length = decoded.length - (isPublicKey ? 2 : 1);
  // calculate the hash and do the checksum byte checks  const hash = sshash(decoded.subarray(0, length));  const isValid = (decoded[0] & 0b1000_0000) === 0 && ![46, 47].includes(decoded[0]) && (    isPublicKey      ? decoded[decoded.length - 2] === hash[0] && decoded[decoded.length - 1] === hash[1]      : decoded[decoded.length - 1] === hash[0]  );
  return [isValid, length, ss58Length, ss58Decoded];}