    fn receive_cross_chain_callback(ref self: ContractState, cross_chain_msg_id: felt252, from_chain: felt252, to_chain: felt252,
        from_handler: u256, to_handler: ContractAddress, cross_chain_msg_status: u8) -> bool{
        assert(to_handler == get_contract_address(),'error to_handler');
        assert(self.settlement_address.read() == get_caller_address(), 'not settlement');
        assert(self.support_handler.read((from_chain, from_handler)) && 
                self.support_handler.read((to_chain, contract_address_to_u256(to_handler))), 'not support handler');

        // ... rest of the function
    }
function receive_cross_chain_callback(
    uint256 txid,
    string memory from_chain,
    uint256 from_handler,
    CrossChainMsgStatus status,
    uint8 /* sign_type */,
    bytes calldata /* signatures */
) external onlySettlement returns (bool) {
    if (is_valid_handler(from_chain, from_handler) == false) {
        return false;
    }

    // ... rest of the function
}
  function processCrossChainCallback(
        uint256 txid,
        string memory from_chain,
        uint256 from_handler,
        address to_handler,
        CrossChainMsgStatus status,
        uint8 sign_type,
        bytes calldata signatures
    ) internal {
        require(
            create_cross_txs[txid].status == CrossChainMsgStatus.Pending,
            "Invalid transaction status"
        );

        if (
            ISettlementHandler(to_handler).receive_cross_chain_callback(
                txid,
                from_chain,
                from_handler,
                status,
                sign_type,
                signatures
            )
        ) {
            create_cross_txs[txid].status = status;
        } else {
            create_cross_txs[txid].status = CrossChainMsgStatus.Failed;
        }
    }
