Signing Actions

import { encode } from "@msgpack/msgpack";
import { keccak256 } from "viem";

export async function signAction(
  args: {
    wallet: any;
    action: unknown;
    txType: number;
  },
  options?: {
    isTestnet: boolean;
  },
) {
  const isTestnet = options?.isTestnet ?? false;

  const actionBytes = encode(args.action);

  const payloadHash = keccak256(actionBytes);

  const domain = {
    name: "HotstuffCore",
    version: "1",
    chainId: 1,
    verifyingContract:
      "0x1234567890123456789012345678901234567890" as `0x${string}`,
  };

  const types = {
    Action: [
      { name: "source", type: "string" },
      { name: "hash", type: "bytes32" },
      { name: "txType", type: "uint16" },
    ],
  };

  const eip712Message = {
    source: isTestnet ? "Testnet" : "Mainnet",
    hash: payloadHash,
    txType: args.txType,
  };

  const signature = await args.wallet.signTypedData({
    domain,
    types,
    primaryType: "Action",
    message: eip712Message,
  });

  return signature;
}

"""Signing utilities for EIP-712 typed data."""
import msgpack
from eth_account import Account
from eth_account.messages import encode_structured_data
from eth_utils import keccak
from hotstuff.methods.exchange.op_codes import EXCHANGE_OP_CODES


async def sign_action(
    wallet: Account,
    action: dict,
    tx_type: int,
    is_testnet: bool = False
) -> str:
    """
    Sign an action using EIP-712.

    Args:
        wallet: The account to sign with
        action: The action data
        tx_type: The transaction type code
        is_testnet: Whether this is for testnet

    Returns:
        str: The signature
    """
    # Encode action to msgpack
    action_bytes = msgpack.packb(action)

    # Hash the payload
    payload_hash = keccak(action_bytes)

    # EIP-712 domain
    domain = {
        "name": "HotstuffCore",
        "version": "1",
        "chainId": 1,
        "verifyingContract": "0x1234567890123456789012345678901234567890",
    }

    # EIP-712 types
    types = {
        "EIP712Domain": [
            {"name": "name", "type": "string"},
            {"name": "version", "type": "string"},
            {"name": "chainId", "type": "uint256"},
            {"name": "verifyingContract", "type": "address"},
        ],
        "Action": [
            {"name": "source", "type": "string"},
            {"name": "hash", "type": "bytes32"},
            {"name": "txType", "type": "uint16"},
        ],
    }

    # Message
    message = {
        "source": "Testnet" if is_testnet else "Mainnet",
        "hash": payload_hash,
        "txType": tx_type,
    }

    # Create structured data
    structured_data = {
        "types": types,
        "primaryType": "Action",
        "domain": domain,
        "message": message,
    }

    # Encode and sign
    encoded_data = encode_structured_data(structured_data)
    signed_message = wallet.sign_message(encoded_data)

    return signed_message.signature.hex()