Callback called by Provable.

ProvableBetFunctionCallback.solidity

    function __callback( bytes32 _queryId, string memory _result, bytes memory _proof ) public {
        require(msg.sender == provable_cbAddress());
        require(ongoingBets[_queryId].sender != address(0x0) , 'query does not exist');
        if(provable_randomDS_proofVerify__returnCode( _queryId, _result, _proof) != 0){
            revert();
        } else {
            uint ceiling = (MAX_INT_FROM_BYTE ** NUM_RANDOM_BYTES_REQUESTED) - 1;
            uint randomNumber = uint(keccak256(abi.encodePacked(_result))) % ceiling;
            uint spin = (randomNumber % 100) + 1;
            Bet memory bet = ongoingBets[_queryId];
            if(spin < bet.spinUnder){
                addAmountToUser(bet.sender, bet.prize);
            }
            emit logBetSuccess(bet.sender, spin, bet.spinUnder, bet.stake, bet.prize, bet.payout, balances[bet.sender]);
            delete ongoingBets[_queryId];
        }
    }