Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity 0.8.20;
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
contract Moon is Context, ERC20, Ownable {
using SafeMath for uint256;
IUniswapV2Router02 private _uniswapV2Router02;
mapping(address => bool) private _excludedFromFees;
mapping(address => bool) private _excludedFromMaxTxAmount;
bool public tradingOpen = false;
bool private _swapping = false;
bool public swapEnabled = false;
bool public feesEnabled = true;
bool public transferFeesEnabled = false;
uint256 public maxBuyAmount;
uint256 public maxSellAmount;
uint256 public maxWalletAmount;
uint256 private _totalFees;
uint256 private _marketingFee;
uint256 public buyMarketingFee = 10;
uint256 private _previousBuyMarketingFee = buyMarketingFee;
uint256 public sellMarketingFee = 10;
uint256 private _previousSellMarketingFee = sellMarketingFee;
uint256 public transferMarketingFee = 10;
uint256 private _previousTransferMarketingFee = transferMarketingFee;
uint256 private _tokensForMarketing;
uint256 private _swapTokensAtAmount = 0;
address payable public marketingWalletAddress =
payable(0x06AE8571Dd5124EdE5f634A6422dDB9F5b5c68D6);
address private _uniswapV2Pair;
enum TransactionType {
BUY,
SELL,
TRANSFER
}
modifier lockSwapping() {
_swapping = true;
_;
_swapping = false;
}
event OpenTrading();
event SetMaxBuyAmount(uint256 newMaxBuyAmount);
event SetMaxSellAmount(uint256 newMaxSellAmount);
event SetMaxWalletAmount(uint256 newMaxWalletAmount);
event SetSwapTokensAtAmount(uint256 newSwapTokensAtAmount);
event SetBuyFee(uint256 buyMarketingFee);
event SetSellFee(uint256 sellMarketingFee);
event SetTransferFee(uint256 transferMarketingFee);
constructor() ERC20("Moon Coin", "MOON") {
uint256 _totalSupply = 100_000_000 ether;
if (block.chainid == 1 || block.chainid == 5)
_uniswapV2Router02 = IUniswapV2Router02(
0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
); // ETH: Uniswap V2
else if (block.chainid == 56)
_uniswapV2Router02 = IUniswapV2Router02(
0x10ED43C718714eb63d5aA57B78B54704E256024E
); // BSC Chain: PCS V2
else if (block.chainid == 42161)
_uniswapV2Router02 = IUniswapV2Router02(
0x1b02dA8Cb0d097eB8D57A175b88c7D8b47997506
); // ARB Chain: SushiSwap
else revert("Chain not set.");
_approve(address(this), address(_uniswapV2Router02), totalSupply());
_uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router02.factory())
.createPair(address(this), _uniswapV2Router02.WETH());
IERC20(_uniswapV2Pair).approve(
address(_uniswapV2Router02),
type(uint256).max
);
maxBuyAmount = _totalSupply;
maxSellAmount = _totalSupply;
maxWalletAmount = _totalSupply;
_excludedFromFees[owner()] = true;
_excludedFromFees[address(this)] = true;
_excludedFromFees[address(0xdead)] = true;
_excludedFromFees[marketingWalletAddress] = true;
_excludedFromMaxTxAmount[owner()] = true;
_excludedFromMaxTxAmount[address(this)] = true;
_excludedFromMaxTxAmount[address(0xdead)] = true;
_excludedFromMaxTxAmount[marketingWalletAddress] = true;
_mint(owner(), _totalSupply);
}
receive() external payable {}
fallback() external payable {}
function _transfer(
address from,
address to,
uint256 amount
) internal override {
require(from != address(0x0), "ERC20: transfer from the zero address");
require(to != address(0x0), "ERC20: transfer to the zero address");
require(amount > 0, "Transfer amount must be greater than zero");
bool takeFee = true;
TransactionType txType = (from == _uniswapV2Pair)
? TransactionType.BUY
: (to == _uniswapV2Pair)
? TransactionType.SELL
: TransactionType.TRANSFER;
if (
from != owner() &&
to != owner() &&
to != address(0x0) &&
to != address(0xdead) &&
!_swapping
) {
if (!tradingOpen)
require(
_excludedFromFees[from] || _excludedFromFees[to],
"Trading is not allowed yet."
);
if (
txType == TransactionType.BUY &&
to != address(_uniswapV2Router02) &&
!_excludedFromMaxTxAmount[to]
) {
require(
amount <= maxBuyAmount,
"Transfer amount exceeds the maxBuyAmount."
);
require(
balanceOf(to).add(amount) <= maxWalletAmount,
"Exceeds maximum wallet token amount."
);
}
if (
txType == TransactionType.SELL &&
from != address(_uniswapV2Router02) &&
!_excludedFromMaxTxAmount[from]
)
require(
amount <= maxSellAmount,
"Transfer amount exceeds the maxSellAmount."
);
}
if (
_excludedFromFees[from] ||
_excludedFromFees[to] ||
!feesEnabled ||
(!transferFeesEnabled && txType == TransactionType.TRANSFER)
) takeFee = false;
uint256 contractBalance = balanceOf(address(this));
bool canSwap = (contractBalance > _swapTokensAtAmount) &&
(txType == TransactionType.SELL);
if (
canSwap &&
swapEnabled &&
!_swapping &&
!_excludedFromFees[from] &&
!_excludedFromFees[to]
) {
_swapBack(contractBalance);
}
_tokenTransfer(from, to, amount, takeFee, txType);
}
function _swapBack(uint256 contractBalance) internal lockSwapping {
bool success;
if (contractBalance == 0 || _tokensForMarketing == 0) return;
if (contractBalance > _swapTokensAtAmount.mul(5))
contractBalance = _swapTokensAtAmount.mul(5);
_swapTokensForETH(contractBalance);
_tokensForMarketing = 0;
(success, ) = address(marketingWalletAddress).call{
value: address(this).balance
}("");
}
function _swapTokensForETH(uint256 tokenAmount) internal {
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = _uniswapV2Router02.WETH();
_approve(address(this), address(_uniswapV2Router02), tokenAmount);
_uniswapV2Router02.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0,
path,
address(this),
block.timestamp
);
}
function _sendETHToFee(uint256 amount) internal {
marketingWalletAddress.transfer(amount);
}
function openTrading() public onlyOwner {
require(!tradingOpen, "Trading is already open");
maxBuyAmount = totalSupply().mul(1).div(100);
maxSellAmount = totalSupply().mul(1).div(100);
maxWalletAmount = totalSupply().mul(1).div(100);
_swapTokensAtAmount = totalSupply().mul(5).div(10000);
swapEnabled = true;
tradingOpen = true;
emit OpenTrading();
}
function setSwapEnabled(bool onoff) public onlyOwner {
swapEnabled = onoff;
}
function setFeesEnabled(bool onoff) public onlyOwner {
feesEnabled = onoff;
}
function setTransferFeesEnabled(bool onoff) public onlyOwner {
transferFeesEnabled = onoff;
}
function setMaxBuyAmount(uint256 _maxBuyAmount) public onlyOwner {
require(
_maxBuyAmount >= (totalSupply().mul(1).div(1000)),
"Max buy amount cannot be lower than 0.1% total supply."
);
maxBuyAmount = _maxBuyAmount;
emit SetMaxBuyAmount(maxBuyAmount);
}
function setMaxSellAmount(uint256 _maxSellAmount) public onlyOwner {
require(
_maxSellAmount >= (totalSupply().mul(1).div(1000)),
"Max sell amount cannot be lower than 0.1% total supply."
);
maxSellAmount = _maxSellAmount;
emit SetMaxSellAmount(maxSellAmount);
}
function setMaxWalletAmount(uint256 _maxWalletAmount) public onlyOwner {
require(
_maxWalletAmount >= (totalSupply().mul(1).div(1000)),
"Max wallet amount cannot be lower than 0.1% total supply."
);
maxWalletAmount = _maxWalletAmount;
emit SetMaxWalletAmount(maxWalletAmount);
}
function setSwapTokensAtAmount(uint256 swapTokensAtAmount)
public
onlyOwner
{
require(
swapTokensAtAmount >= (totalSupply().mul(1).div(1000000)),
"Swap amount cannot be lower than 0.0001% total supply."
);
require(
swapTokensAtAmount <= (totalSupply().mul(5).div(1000)),
"Swap amount cannot be higher than 0.5% total supply."
);
_swapTokensAtAmount = swapTokensAtAmount;
emit SetSwapTokensAtAmount(_swapTokensAtAmount);
}
function setMarketingWalletAddress(address _marketingWalletAddress)
public
onlyOwner
{
require(
_marketingWalletAddress != address(0x0),
"marketingWalletAddress cannot be 0"
);
_excludedFromFees[marketingWalletAddress] = false;
_excludedFromMaxTxAmount[marketingWalletAddress] = false;
marketingWalletAddress = payable(_marketingWalletAddress);
_excludedFromFees[marketingWalletAddress] = true;
_excludedFromMaxTxAmount[marketingWalletAddress] = true;
}
function excludeFromFees(address[] memory accounts, bool isEx)
public
onlyOwner
{
for (uint256 i = 0; i < accounts.length; i++)
_excludedFromFees[accounts[i]] = isEx;
}
function excludeFromMaxTxAmount(address[] memory accounts, bool isEx)
public
onlyOwner
{
for (uint256 i = 0; i < accounts.length; i++)
_excludedFromMaxTxAmount[accounts[i]] = isEx;
}
function setBuyFee(uint256 _buyMarketingFee) public onlyOwner {
require(_buyMarketingFee <= 12, "Must keep buy taxes below 12%");
buyMarketingFee = _buyMarketingFee;
emit SetBuyFee(buyMarketingFee);
}
function setSellFee(uint256 _sellMarketingFee) public onlyOwner {
require(_sellMarketingFee <= 12, "Must keep sell taxes below 12%");
sellMarketingFee = _sellMarketingFee;
emit SetSellFee(sellMarketingFee);
}
function setTransferFee(uint256 _transferMarketingFee) public onlyOwner {
require(
_transferMarketingFee <= 12,
"Must keep transfer taxes below 12%"
);
transferMarketingFee = _transferMarketingFee;
emit SetTransferFee(transferMarketingFee);
}
function _removeAllFee() internal {
if (
buyMarketingFee == 0 &&
sellMarketingFee == 0 &&
transferMarketingFee == 0
) return;
_previousBuyMarketingFee = buyMarketingFee;
_previousSellMarketingFee = sellMarketingFee;
_previousTransferMarketingFee = transferMarketingFee;
buyMarketingFee = 0;
sellMarketingFee = 0;
transferMarketingFee = 0;
}
function _restoreAllFee() internal {
buyMarketingFee = _previousBuyMarketingFee;
sellMarketingFee = _previousSellMarketingFee;
transferMarketingFee = _previousTransferMarketingFee;
}
function _tokenTransfer(
address sender,
address recipient,
uint256 amount,
bool takeFee,
TransactionType txType
) internal {
if (!takeFee) _removeAllFee();
else amount = _takeFees(sender, amount, txType);
super._transfer(sender, recipient, amount);
if (!takeFee) _restoreAllFee();
}
function _takeFees(
address sender,
uint256 amount,
TransactionType txType
) internal returns (uint256) {
if (txType == TransactionType.SELL) _sell();
else if (txType == TransactionType.BUY) _buy();
else if (txType == TransactionType.TRANSFER) _transfer();
else revert("Invalid transaction type.");
uint256 fees;
if (_totalFees > 0) {
fees = amount.mul(_totalFees).div(100);
_tokensForMarketing += (fees.mul(_marketingFee)).div(_totalFees);
}
if (fees > 0) super._transfer(sender, address(this), fees);
return amount -= fees;
}
function _sell() internal {
_marketingFee = sellMarketingFee;
_totalFees = _marketingFee;
}
function _buy() internal {
_marketingFee = buyMarketingFee;
_totalFees = _marketingFee;
}
function _transfer() internal {
_marketingFee = transferMarketingFee;
_totalFees = _marketingFee;
}
function fixClog() public onlyOwner lockSwapping {
_swapTokensForETH(balanceOf(address(this)));
_tokensForMarketing = 0;
bool success;
(success, ) = address(marketingWalletAddress).call{
value: address(this).balance
}("");
}
function rescueStuckTokens(address tkn) public onlyOwner {
bool success;
if (tkn == address(0))
(success, ) = address(msg.sender).call{
value: address(this).balance
}("");
else {
require(tkn != address(this), "Cannot withdraw own token");
require(IERC20(tkn).balanceOf(address(this)) > 0, "No tokens");
uint256 amount = IERC20(tkn).balanceOf(address(this));
IERC20(tkn).transfer(msg.sender, amount);
}
}
function removeLimits() public onlyOwner {
maxBuyAmount = totalSupply();
maxSellAmount = totalSupply();
maxWalletAmount = totalSupply();
}
}
pragma solidity >=0.6.2;
import './IUniswapV2Router01.sol';
interface IUniswapV2Router02 is IUniswapV2Router01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountETH);
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
}
pragma solidity >=0.5.0;
interface IUniswapV2Factory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint);
function feeTo() external view returns (address);
function feeToSetter() external view returns (address);
function getPair(address tokenA, address tokenB) external view returns (address pair);
function allPairs(uint) external view returns (address pair);
function allPairsLength() external view returns (uint);
function createPair(address tokenA, address tokenB) external returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol)
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
* @dev Wrappers over Solidity's arithmetic operations.
*
* NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
* now has built in overflow checking.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the subtraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b > a) return (false, 0);
return (true, a - b);
}
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a / b);
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a % b);
}
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
return a + b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
return a * b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator.
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b <= a, errorMessage);
return a - b;
}
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a / b;
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a % b;
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is Context, IERC20, IERC20Metadata {
mapping(address => uint256) private _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* The default value of {decimals} is 18. To select a different value for
* {decimals} you should overload it.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the value {ERC20} uses, unless this function is
* overridden;
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view virtual override returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view virtual override returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address to, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_transfer(owner, to, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual override returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
* `transferFrom`. This is semantically equivalent to an infinite approval.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_approve(owner, spender, amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* NOTE: Does not update the allowance if the current allowance
* is the maximum `uint256`.
*
* Requirements:
*
* - `from` and `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
* - the caller must have allowance for ``from``'s tokens of at least
* `amount`.
*/
function transferFrom(
address from,
address to,
uint256 amount
) public virtual override returns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, amount);
_transfer(from, to, amount);
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
address owner = _msgSender();
_approve(owner, spender, allowance(owner, spender) + addedValue);
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
address owner = _msgSender();
uint256 currentAllowance = allowance(owner, spender);
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(owner, spender, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Moves `amount` of tokens from `from` to `to`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
*/
function _transfer(
address from,
address to,
uint256 amount
) internal virtual {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(from, to, amount);
uint256 fromBalance = _balances[from];
require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[from] = fromBalance - amount;
// Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
// decrementing then incrementing.
_balances[to] += amount;
}
emit Transfer(from, to, amount);
_afterTokenTransfer(from, to, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply += amount;
unchecked {
// Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
_balances[account] += amount;
}
emit Transfer(address(0), account, amount);
_afterTokenTransfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
// Overflow not possible: amount <= accountBalance <= totalSupply.
_totalSupply -= amount;
}
emit Transfer(account, address(0), amount);
_afterTokenTransfer(account, address(0), amount);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(
address owner,
address spender,
uint256 amount
) internal virtual {
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);
}
/**
* @dev Updates `owner` s allowance for `spender` based on spent `amount`.
*
* Does not update the allowance amount in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Might emit an {Approval} event.
*/
function _spendAllowance(
address owner,
address spender,
uint256 amount
) internal virtual {
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance != type(uint256).max) {
require(currentAllowance >= amount, "ERC20: insufficient allowance");
unchecked {
_approve(owner, spender, currentAllowance - amount);
}
}
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {}
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* has been transferred to `to`.
* - when `from` is zero, `amount` tokens have been minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens have been burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _afterTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
pragma solidity >=0.6.2;
interface IUniswapV2Router01 {
function factory() external pure returns (address);
function WETH() external pure returns (address);
function addLiquidity(
address tokenA,
address tokenB,
uint amountADesired,
uint amountBDesired,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB, uint liquidity);
function addLiquidityETH(
address token,
uint amountTokenDesired,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external payable returns (uint amountToken, uint amountETH, uint liquidity);
function removeLiquidity(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB);
function removeLiquidityETH(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountToken, uint amountETH);
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountA, uint amountB);
function removeLiquidityETHWithPermit(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountToken, uint amountETH);
function swapExactTokensForTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapTokensForExactTokens(
uint amountOut,
uint amountInMax,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 amount
) external returns (bool);
}