Sign and verify message on Keplr

sign and verify.ts

export const signMessage = async (
  chainId: string,
  address: string,
): Promise<StdSignature | undefined> => {
  const anyWindow: any = window;

  if (!anyWindow.getOfflineSigner) {
    throw new Error('Keplr extension is not available');
  }
  const signed = await window.keplr?.signArbitrary(
    chainId,
    address,
    SIGN_MSG.value,
  );

  return signed;
};

export const verifyMessage = (account: Key, signed: StdSignature): boolean => {
  const isValid = verifyADR36Amino(
    PUBLIC_ENVIRONMENT.NEXT_PUBLIC_ADDRESS_PREFIX,
    account.bech32Address,
    SIGN_MSG.value,
    fromBase64(signed.pub_key.value),
    fromBase64(signed.signature),
  );

  return isValid;
};