Hello
I already developed a reflect coin token and need your review so prevent bad happen after deployed on pancakeswap. Please check out my scripts below:
// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol";
import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol";
import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
/*
*/
contract ExampleCoin is Context, IERC20, Ownable {
using SafeMath for uint256;
using Address for address;
/* Maps */
mapping (address => uint256) private _rOwned;
mapping (address => mapping (address => uint256)) private _allowances;
mapping (address => bool) private _isExcludedFromFee;
/* Naming */
string private _name = "ExampleCoin";
string private _symbol = "EXC";
/* Decimal handling */
uint8 private _decimals = 18;
uint256 private _decimalFactor = 10**_decimals;
/* Total supply, total reflected supply and total fees taken */
uint256 private constant MAX = ~uint256(0); // Maximum uint256
uint256 private _tTotal = 10**8 * _decimalFactor; // Tokens total
uint256 private _rTotal = MAX - (MAX % _tTotal); // Reflections total
uint256 private _tFeeTotal; // Token Fee Total (total fees gathered)
/* Transaction restrictions */
uint256 public _maxTxAmount = 2 * 10**6 * _decimalFactor;
uint256 public _minTxAmount = 10**2 * _decimalFactor;
/* Fees */
uint256 public _taxFee = 3;
uint256 public _previousTaxFee = _taxFee;
uint256 public _liqFee = 3;
uint256 public _previousLiqFee = _liqFee;
uint256 public _marketingFee = 2;
uint256 public _previousMarketingFee = _marketingFee;
uint256 public _developerFee = 2;
uint256 public _previousDeveloperFee = _developerFee;
/* Payable fee wallets */
address payable _developerAddress;
address payable _marketingAddress;
/* PancakeSwap */
IUniswapV2Router02 public uniswapV2Router;
address public uniswapV2Pair;
/* Security utils */
// Mutex lock for taking fees (calls untrusted external contracts)
bool takeFeesMutexLock;
modifier lockTakeFees {
takeFeesMutexLock = true;
_;
takeFeesMutexLock = false;
}
constructor() {
_rOwned[_msgSender()] = _rTotal;
createPancakeSwapPair();
_isExcludedFromFee[owner()] = true;
_isExcludedFromFee[address(this)] = true;
emit Transfer(address(0), _msgSender(), _tTotal);
}
// -------> PancakeSwap functions
receive() external payable {} // to recieve ETH from uniswapV2Router when swaping
function createPancakeSwapPair() public onlyOwner {
// IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x10ED43C718714eb63d5aA57B78B54704E256024E); // MAINNET
IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0xD99D1c33F9fC3444f8101754aBC46c52416550D1); // TESTNET
// Create a uniswap pair for this new token
uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
.createPair(address(this), _uniswapV2Router.WETH());
// Set router contract variable
uniswapV2Router = _uniswapV2Router;
}
function swapTokensForEth(uint256 tokenAmount) private {
// Generate the uniswap pair path of token -> WETH
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = uniswapV2Router.WETH();
_approve(address(this), address(uniswapV2Router), tokenAmount);
// Make the swap
uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0, // accept any amount of ETH
path,
address(this),
block.timestamp
);
}
function addLiquidity(uint256 tokenAmount, uint256 ethAmount, address partner) private {
// Approve token transfer to cover all possible scenarios
_approve(address(this), address(uniswapV2Router), tokenAmount);
// Add the liquidity
uniswapV2Router.addLiquidityETH{value: ethAmount}(
address(this),
tokenAmount,
0, // slippage is unavoidable
0, // slippage is unavoidable
partner,
block.timestamp
);
}
// <------- PancakeSwap functions
/* BEP20 functions */
function name() public view returns (string memory) {
return _name;
}
function symbol() public view returns (string memory) {
return _symbol;
}
function decimals() public view returns (uint8) {
return _decimals;
}
function totalSupply() public view override returns (uint256) {
return _tTotal;
}
function balanceOf(address account) public view override returns (uint256) {
return tokenFromReflection(_rOwned[account]);
}
function transfer(address recipient, uint256 amount) public override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
return true;
}
function allowance(address owner, address spender) public view override returns (uint256) {
return _allowances[owner][spender];
}
function approve(address spender, uint256 amount) public override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
/* BEP20 functions */
/* Reflection utilities ---> */
function tokenFromReflection(uint256 rAmount) public view returns(uint256) {
require(rAmount <= _rTotal, "Amount must be less than total reflections");
uint256 currentRate = _getRate();
return rAmount.div(currentRate);
}
function _reflectFee(uint256 rFee, uint256 tFee) private {
_rTotal = _rTotal.sub(rFee);
_tFeeTotal = _tFeeTotal.add(tFee);
}
function _getRate() private view returns(uint256) {
return _rTotal.div(_tTotal);
}
/* <--- Reflection utilities */
/* Private internal contract functions */
function _approve(address owner, address spender, uint256 amount) private {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
function _transfer(address from, address to, uint256 amount) private {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
require(amount > 0, "Transfer amount must be greater than zero");
if (from != owner() && to != owner())
require(amount <= _maxTxAmount, "Transfer amount exceeds the maxTxAmount.");
if (from != owner() && to != owner())
require(amount >= _minTxAmount, "Transfer amount cannot be smaller than minTxAmount.");
bool takeFee = true;
// Do not take fee if the sender should be excluded
if (_isExcludedFromFee[from]) {
takeFee = false;
}
// Don't take any fees if marketing address or developer addresses aren't set.
if (_marketingAddress == address(0) || _developerAddress == address(0)) {
takeFee = false;
}
if (
takeFee &&
from != uniswapV2Pair &&
!takeFeesMutexLock
) {
// Subtract the transfer amount left after fees
uint256 totalFee = _developerFee.add(_marketingFee).add(_liqFee);
uint256 totalFeeAmount = amount.mul(totalFee).div(100);
uint256 oldAmount = amount;
amount = amount.sub(totalFeeAmount);
// Take fees
_takeFees(oldAmount, from);
}
// Transfer the amount left of the transfer (and also take reflection tax fee here)
_tokenTransfer(from, to, amount, takeFee);
}
function _takeFees(uint256 amount, address from) private lockTakeFees {
// Calculate the wallet fees to take (partnership and marketing) - don't
// take reflect tax or liquidity here
uint256 walletFee = _developerFee.add(_marketingFee);
uint256 walletFeeAmount = amount.mul(walletFee).div(100);
// Calculate liquidity fee amount, and split it into two halves, one for
// the amount of tokens, and the other half will represent the amount of
// tokens to be swapped into ETH
uint256 totalLiqFeeAmount = amount.mul(_liqFee).div(100);
uint256 liqFeeAmount = totalLiqFeeAmount.div(2);
uint256 liqFeeToBeSwappedToETHAmount = totalLiqFeeAmount.sub(liqFeeAmount);
// Total fees that will have been taken away from the amount of tokens
uint256 totalFeeAmount = walletFeeAmount.add(totalLiqFeeAmount);
uint256 totalFeeAmountToBeSwappedForETH = walletFeeAmount.add(liqFeeToBeSwappedToETHAmount);
// Capture the contract's current ETH balance
uint256 initialBalance = address(this).balance;
// Send the tokens taken as fee to the contract to be able to swap
// them for ETH (the contract address needs the token balance)
_tokenTransfer(from, address(this), totalFeeAmount, false);
require(
balanceOf(address(this)) >= totalFeeAmountToBeSwappedForETH,
"Contract address does not have the available token balance to perform swap"
);
// Swap the required amount of tokens for ETH
swapTokensForEth(totalFeeAmountToBeSwappedForETH);
// How much ETH did we just swap into?
uint256 swappedETH = address(this).balance.sub(initialBalance);
// This multiplies the liquidity fee by 10 to avoid halving imprecisions on odd integers
uint256 totalFeeToBeSwappedForETHMul10 = _liqFee.mul(10).div(2).add(walletFee.mul(10));
// Calculate developer and marketing portions of the swapped ETH (also remember to multiply this factor by 10)
uint256 developerETHPortion = swappedETH.div(totalFeeToBeSwappedForETHMul10).mul(_developerFee.mul(10));
uint256 marketingETHPortion = swappedETH.div(totalFeeToBeSwappedForETHMul10).mul(_marketingFee.mul(10));
// To avoid annoying halving errors, the rest of the ETH portion
// should be exactly what was supposed to be added to the liquidity
// pool. Thus we can just subtract from the remaining swappedETH
// instead of calculating the exact fee percentage.
uint256 totalETHPortionForWallets = developerETHPortion.add(marketingETHPortion);
uint256 liquidityPoolETHPortion = swappedETH.sub(totalETHPortionForWallets);
// Transfer ETH to fee wallets
(bool sent, bytes memory data) = _developerAddress.call{value: developerETHPortion}("");
require(sent, 'ETH was not sent to developer');
(sent, data) = _marketingAddress.call{value: marketingETHPortion}("");
require(sent, 'ETH was not sent to marketing');
// Liquidity pool ETH was calculated from the swappedETH, and the
// liqFeeAmount was the tokens calculated earlier representing the
// other half of the liquidity fee.
addLiquidity(liqFeeAmount, liquidityPoolETHPortion, owner());
}
function _tokenTransfer(address sender, address recipient, uint256 amount, bool takeFee) private {
if (!takeFee) {
removeAllFees();
}
_transferStandard(sender, recipient, amount);
if (!takeFee) {
restoreAllFees();
}
}
function _transferStandard(address sender, address recipient, uint256 tAmount) private {
(uint256 rAmount, uint256 rTransferAmount, uint256 rFee, uint256 tTransferAmount, uint256 tFee) = _getValues(tAmount);
_rOwned[sender] = _rOwned[sender].sub(rAmount);
_rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);
_reflectFee(rFee, tFee);
emit Transfer(sender, recipient, tTransferAmount);
}
function _getValues(uint256 tAmount) private view returns (uint256, uint256, uint256, uint256, uint256) {
(uint256 tTransferAmount, uint256 tFee) = _getTValues(tAmount);
(uint256 rAmount, uint256 rTransferAmount, uint256 rFee) = _getRValues(tAmount, tFee, _getRate());
return (rAmount, rTransferAmount, rFee, tTransferAmount, tFee);
}
function _getTValues(uint256 tAmount) private view returns (uint256, uint256) {
uint256 tFee = calculateTaxFee(tAmount);
uint256 tTransferAmount = tAmount.sub(tFee);
return (tTransferAmount, tFee);
}
function _getRValues(uint256 tAmount, uint256 tFee, uint256 currentRate) private pure returns (uint256, uint256, uint256) {
uint256 rAmount = tAmount.mul(currentRate);
uint256 rFee = tFee.mul(currentRate);
uint256 rTransferAmount = rAmount.sub(rFee);
return (rAmount, rTransferAmount, rFee);
}
function calculateTaxFee(uint256 _amount) private view returns (uint256) {
return _amount.mul(_taxFee).div(100);
}
function calculateLiquidityFee(uint256 _amount) private view returns (uint256) {
return _amount.mul(_liqFee).div(100);
}
function calculateMarketingFee(uint256 _amount) private view returns (uint256) {
return _amount.mul(_marketingFee).div(100);
}
function calculateDeveloperFee(uint256 _amount) private view returns (uint256) {
return _amount.mul(_developerFee).div(100);
}
function removeAllFees() private {
if(_taxFee == 0 && _marketingFee == 0 && _developerFee == 0 && _liqFee == 0) return;
_previousTaxFee = _taxFee;
_previousDeveloperFee = _developerFee;
_previousMarketingFee = _marketingFee;
_previousLiqFee = _liqFee;
_taxFee = 0;
_liqFee = 0;
_developerFee = 0;
_marketingFee = 0;
}
function restoreAllFees() private {
_taxFee = _previousTaxFee;
_developerFee = _previousDeveloperFee;
_marketingFee = _previousMarketingFee;
_liqFee = _previousLiqFee;
}
/* Private internal contract functions */
/* Public setters */
function setMaxTxPercent(uint256 maxTxPercent) external onlyOwner {
_maxTxAmount = _tTotal.mul(maxTxPercent).div(
10**2
);
}
function setTaxFeePercent(uint256 taxFee) external onlyOwner {
_previousTaxFee = _taxFee;
_taxFee = taxFee;
}
function setLiqFeePercent(uint256 liqFee) external onlyOwner {
_previousLiqFee = _liqFee;
_liqFee = liqFee;
}
function setDeveloperFeePercent(uint256 developerFee) external onlyOwner {
_previousDeveloperFee = _developerFee;
_developerFee = developerFee;
}
function setMarketingFeePercent(uint256 marketingFee) external onlyOwner {
_previousMarketingFee = _marketingFee;
_marketingFee = marketingFee;
}
function setDeveloperAddress(address payable developer) public onlyOwner {
_developerAddress = developer;
}
function setMarketingAddress(address payable marketing) public onlyOwner {
_marketingAddress = marketing;
}
function excludeFromFee(address account) public onlyOwner {
_isExcludedFromFee[account] = true;
}
function includeInFee(address account) public onlyOwner {
_isExcludedFromFee[account] = false;
}
/* Public setters */
/* Public getters */
function isExcludedFromFee(address account) public view returns(bool) {
return _isExcludedFromFee[account];
}
function showDeveloperAddress() public view returns(address payable) {
return _developerAddress;
}
function showMarketingAddress() public view returns(address payable) {
return _marketingAddress;
}
function getPairAddress() public view returns (address) {
return uniswapV2Pair;
}
/* Public getters */
}
Examplecoin token tokenomics:
- Max Supply: 100,000,000
- Max TX: 2,000,000 (2%)
- Min TX: 100 (0.0001%)
- 3% of all sells are automatically redistributed to all holders
- 3% fee is automatically added to the liquidity pool
- 2% fee goes to a "marketing address"
- 1% fee goes to a "developer address"
My other issues:
- Can I use this token for presale in pinksale?
- How I can change max supply become infinite supply?
Regards
