function setTax(uint256 _transferTax, uint256 precision) external nonReentrant onlyOwner {

_validateTaxValues(_transferTax, precision);

uint256 old = s.transferTax;
uint256 oldP = s.taxPrecision;
s.transferTax = _transferTax;
s.taxPrecision = precision;

emit TaxChanged(_msgSender(), old, oldP, _transferTax, precision);
}

function _validateTaxValues(uint256 _transferTax, uint256 precision) internal pure returns(bool){
string memory precisionErrorMsg = "Allowed Values: 0, 1, 2";
string memory transferTaxErrorMsg = "Allowed Values: P 0 T [0 - 12] | P 1 T [0 - 125] | P 2 T [0 - 1250]";

if (precision > 2) revert InvalidPrecisionValue(precisionErrorMsg);
// sets the max tax for 0 precision to 12 percent
if (precision == 0 && _transferTax > 12) revert InvalidTransferTaxValue(transferTaxErrorMsg);
// sets the max tax for 1 precision to 12.5 percent
if (precision == 1 && _transferTax > 125) revert InvalidTransferTaxValue(transferTaxErrorMsg);
// sets the max tax for 2 precision to 12.50 percent
if (precision == 2 && _transferTax > 1250) revert InvalidTransferTaxValue(transferTaxErrorMsg);

return true;
}

/**
* @custom:function-name calcFeeWithPrecision
* @dev calculates the precise amount in fee
*
* `originalAmount` - the originalAmount to be converted
* `fee` - the amount of fee to be outputed in percent based on the precision
* `precision` - number of decimal places between 0 and 1 or the amount of 0
* after 100 to accomodate uint's lack of decimal numbers
*
* precision | range
* 0 | 100 = 100% and 1 = 1% | cap should be 12 -> 12%
* 1 | 1_000 = 100% and 1 - 0.1% | cap should be 125 -> 12.5%
* 2 | 10_000 = 100% and 1 = 0.01% | cap should be 1250 -> 12.5%
*
* more precision means more zeroes between 0 and 1
*
* Limitations:
* when the result underflows it will return 0
*/
function calcFeeWithPrecision(uint256 originalAmount, uint256 fee, uint256 precision) internal pure returns(uint256) {

uint256 denominator = (10 ** ( 2 + (1 * precision) ) );

// this part is necessary to make sure that the function won't use a fee/percentage
// more than 100 percent
if (fee > denominator) revert InvalidFeeError("Fee can't exceed the denominator");

return (originalAmount * fee) / denominator;
}

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