Sign Typed Messages in Bitcoin

const transactionPayload = {
  operation: TransactionOperation.TypedMessage,
  assetId: "BTC",
  source: {
    type: TransferPeerPathType.VaultAccount,
    id: "0", // The vault account ID represnting the address used to sign
  },
  note: "Bitcoin Message",
  extraParameters: {
    rawMessageData: {
      messages: [
        {
          content: "", // Content remains blank and is replaced by the message built when signing the TX
          type: "BTC_MESSAGE",
        },
      ],
    },
  },
};
const getWalletAddress = async (): Promise<VaultWalletAddress | any> => {
  try {
    const addressResponse =
      await fireblocks.vaults.getVaultAccountAssetAddressesPaginated({
        vaultAccountId: transactionPayload.source.id,
        assetId: transactionPayload.assetId,
      });
    if (addressResponse.data.addresses.length === 0) {
      throw new Error("No wallet addresses found");
    }
    return addressResponse.data;
  } catch (error) {
    console.error(error);
  }
};

const getTxStatus = async (txId: string): Promise<TransactionResponse> => {
  try {
    let response: FireblocksResponse<TransactionResponse> =
      await fireblocks.transactions.getTransaction({ txId });
    let tx: TransactionResponse = response.data;
    let messageToConsole: string = `Transaction ${tx.id} is currently at status - ${tx.status}`;

    console.log(messageToConsole);
    while (tx.status !== TransactionStateEnum.Completed) {
      await new Promise((resolve) => setTimeout(resolve, 3000));

      response = await fireblocks.transactions.getTransaction({ txId });
      tx = response.data;

      switch (tx.status) {
        case TransactionStateEnum.Blocked:
        case TransactionStateEnum.Cancelled:
        case TransactionStateEnum.Failed:
        case TransactionStateEnum.Rejected:
          throw new Error(
            `Signing request failed/blocked/cancelled: Transaction: ${tx.id} status is ${tx.status}`,
          );
        default:
          console.log(messageToConsole);
          break;
      }
    }
    while (tx.status !== TransactionStateEnum.Completed);
    return tx;
  } catch (error) {
    throw error;
  }
};

const signArbitraryMessage = async (): Promise<
  TransactionResponse | undefined
> => {
  const address = await getWalletAddress();
  try {
    // replacing payload message with the format required before creating the transaction
    // message format is {vasp_prefix}{address}{UUID}
    const message =
      "tripleaio" + address + "975f0090-a88f-4be0-a123-d38484e8394d";
    transactionPayload.extraParameters.rawMessageData.messages[0].content =
      message;

    const transactionResponse = await fireblocks.transactions.createTransaction(
      {
        transactionRequest: transactionPayload,
      },
    );
    const txId = transactionResponse.data.id;
    if (!txId) {
      throw new Error("Transaction ID is undefined.");
    }
    txInfo = await getTxStatus(txId);
    const signature = txInfo.signedMessages[0].signature;

    const encodedSig =
      Buffer.from([Number.parseInt(signature.v, 16) + 31]).toString("hex") +
      signature.fullSig;
    console.log(
      "Encoded Signature:",
      Buffer.from(encodedSig, "hex").toString("base64"),
    );

    return transactionResponse.data;
  } catch (error) {
    console.error(error);
  }
};

signArbitraryMessage();