Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;
import "@openzeppelin/[email protected]/access/Ownable2Step.sol";
import "@openzeppelin/[email protected]/token/ERC20/ERC20.sol";
import {IUniswapV2Factory} from "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import {IUniswapV2Router02} from "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
/// AstraAI is an ERC20 token
contract AstraAI is ERC20, Ownable2Step {
/// custom errors
error CannotRemoveMainPair();
error ZeroAddressNotAllowed();
error FeesLimitExceeds();
error CannotBlacklistLPPair();
error UpdateBoolValue();
error CannotClaimNativeToken();
error AmountTooLow();
error OnlyMarketingWalletAllowed();
error BlacklistedUser();
/// @notice Max limit on Buy / Sell fees
uint256 public constant MAX_FEE_LIMIT = 10;
/// @notice max total supply 10 million tokens (18 decimals)
uint256 private maxSupply = 10_000_000 * 1e18;
/// @notice swap threshold at which collected fees tokens are swapped for ether, autoLP
uint256 public swapTokensAtAmount = 10_000 * 1e18;
/// @notice check if it's a swap tx
bool private inSwap = false;
/// @notice struct buy fees variable
/// marketing: marketing fees
/// autoLP: liquidity fees
struct BuyFees {
uint16 marketing;
uint16 autoLP;
}
/// @notice struct sell fees variable
/// marketing: marketing fees
/// autoLP: liquidity fees
struct SellFees {
uint16 marketing;
uint16 autoLP;
}
/// @notice buyFees variable
BuyFees public buyFee;
/// @notice sellFees variable
SellFees public sellFee;
///@notice initial fees on buy/sell till first 5 buys
uint256 private initialFee;
/// @notice initial fees on buy/sell till next 5 buys
uint256 private midFee;
///@notice number of buys
uint256 buyCount;
/// @notice totalBuyFees
uint256 private totalBuyFee;
/// @notice totalSellFees
uint256 private totalSellFee;
/// @notice marketingWallet
address public marketingWallet;
/// @notice uniswap V2 router address
IUniswapV2Router02 public immutable uniswapV2Router;
/// @notice uniswap V2 Pair address
address public uniswapV2Pair;
/// @notice mapping to manager liquidity pairs
mapping(address => bool) public isAutomatedMarketMaker;
/// @notice mapping to manage excluded address from/to fees
mapping(address => bool) public isExcludedFromFees;
/// @notice mapping to manage blacklist
mapping(address => bool) public isBlacklisted;
//// EVENTS ////
event BuyFeesUpdated(uint16 indexed marketingFee, uint16 indexed liquidityFee);
event SellFeesUpdated(uint16 indexed marketingFee, uint16 indexed liquidityFee);
event FeesSwapped(uint256 indexed ethForLiquidity, uint256 indexed tokensForLiquidity, uint256 indexed ethForMarketing);
/// @dev create an erc20 token using openzeppeling ERC20, Ownable2Step
/// uses uniswap router and factory interface
/// set uniswap router, create pair, initialize buy, sell fees, marketingWallet values
/// excludes the token, marketingWallet and owner address from fees
/// and mint all the supply to owner wallet.
constructor () ERC20("AstraAI", "ASTRA"){
uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), uniswapV2Router.WETH());
isAutomatedMarketMaker[uniswapV2Pair] = true;
initialFee = 15;
midFee = 10;
buyCount = 10;
buyFee.marketing = 4;
buyFee.autoLP = 1;
totalBuyFee = 5;
sellFee.marketing = 4;
sellFee.autoLP = 1;
totalSellFee = 5;
marketingWallet = 0x8f93E7544aEeE2020eB796aF90146890C953ee6E;
isExcludedFromFees[address(this)] = true;
isExcludedFromFees[marketingWallet] = true;
isExcludedFromFees[owner()] = true;
_mint(msg.sender, maxSupply);
}
/// modifier ///
modifier lockTheSwap {
inSwap = true;
_;
inSwap = false;
}
/// receive external ether
receive () external payable {}
/// @dev owner can claim other erc20 tokens, if accidently sent by someone
/// @param _token: token address to be rescued
/// @param _amount: amount to rescued
/// Requirements --
/// Cannot claim native token
function claimOtherERC20 (address _token, uint256 _amount) external onlyOwner {
if(_token == address(this)) {
revert CannotClaimNativeToken();
}
IERC20 tkn = IERC20(_token);
tkn.transfer(owner(), _amount);
}
/// @dev exclude or include a user from/to fees
/// @param user: user address
/// @param value: boolean value. true means excluded. false means included
/// Requirements --
/// zero address not allowed
/// if a user is excluded already, can't exlude him again
function excludeFromFees (address user, bool value) external onlyOwner {
if(user == address(0)){
revert ZeroAddressNotAllowed();
}
if(isExcludedFromFees[user] == value){
revert UpdateBoolValue();
}
isExcludedFromFees[user] = value;
}
/// @dev exclude or include a user from/to blacklist
/// @param user: user address
/// @param value: boolean value. true means blacklisted. false means unblacklisted
/// Requirements --
/// zero address not allowed
/// if a user is blacklisted already, can't blacklist him again
function blacklist (address user, bool value) external onlyOwner {
if(user == address(0)){
revert ZeroAddressNotAllowed();
}
if(isBlacklisted[user] == value){
revert UpdateBoolValue();
}
isBlacklisted[user] = value;
}
/// @dev add or remove new pairs
/// @param _newPair: address to be added or removed as pair
/// @param value: boolean value, true means pair is added, false means pair is removed
/// Requirements --
/// address should not be zero
/// Can not remove main pair
/// can not add already added pairs and vice versa
function manageLiquidityPairs (address _newPair, bool value) external onlyOwner {
if(_newPair == address(0)){
revert ZeroAddressNotAllowed();
}
if(_newPair == uniswapV2Pair){
revert CannotRemoveMainPair();
}
if(isAutomatedMarketMaker[_newPair] == value){
revert UpdateBoolValue();
}
isAutomatedMarketMaker[_newPair] = value;
}
/// update marketing wallet address
function updateMarketingWallet(address _newMarketingWallet) external onlyOwner {
if(_newMarketingWallet == address(0)){
revert ZeroAddressNotAllowed();
}
marketingWallet = _newMarketingWallet;
}
/// @dev update swap tokens at amount threshold
/// @param amount: new threshold amount
function updateSwapTokensAtAmount(uint256 amount) external onlyOwner {
if(amount < 1000){
revert AmountTooLow();
}
swapTokensAtAmount = amount * 1e18;
}
/// @dev update buy fees
/// @param _marketing: marketing fees
/// @param _autoLP: liquidity fees
/// Requirements --
/// total Buy fees must be less than equals to MAX_FEE_LIMIT (10%);
function updateBuyFees (uint16 _marketing, uint16 _autoLP) external onlyOwner {
if(_marketing + _autoLP > MAX_FEE_LIMIT){
revert FeesLimitExceeds();
}
buyFee.marketing = _marketing;
buyFee.autoLP = _autoLP;
totalBuyFee = _marketing + _autoLP;
emit BuyFeesUpdated(_marketing, _autoLP);
}
/// @dev update sell fees
/// @param _marketing: marketing fees
/// @param _autoLP: liquidity fees
/// Requirements --
/// total Sell fees must be less than equals to MAX_FEE_LIMIT (10%);
function updateSellFees (uint16 _marketing, uint16 _autoLP) external onlyOwner {
if(_marketing + _autoLP > MAX_FEE_LIMIT){
revert FeesLimitExceeds();
}
sellFee.marketing = _marketing;
sellFee.autoLP = _autoLP;
totalSellFee = _marketing + _autoLP;
emit SellFeesUpdated(_marketing, _autoLP);
}
/// @notice manage transfers, fees
/// see {ERC20 - _transfer}
/// requirements --
/// from or to should not be zero
function _transfer (address from, address to, uint256 amount) internal override {
if(from == address(0)){
revert ZeroAddressNotAllowed();
}
if(to == address(0)){
revert ZeroAddressNotAllowed();
}
if(isBlacklisted[from] || isBlacklisted[to]){
revert BlacklistedUser();
}
if(amount == 0){
super._transfer(from, to, 0);
return;
}
uint256 contractBalance = balanceOf(address(this));
bool canSwapped = contractBalance >= swapTokensAtAmount;
if(canSwapped && !isAutomatedMarketMaker[from] && !inSwap && !isExcludedFromFees[from] && !isExcludedFromFees[to]){
if(contractBalance > swapTokensAtAmount * 50){
contractBalance = swapTokensAtAmount * 50;
}
swapAndLiquify(contractBalance);
}
bool takeFee = true;
if(isExcludedFromFees[from] || isExcludedFromFees[to]){
takeFee = false;
}
uint256 fees = 0;
uint256 feeDiv = 0;
/// upto first 5 buys, fees is 15 for buy/sell
/// upto next 5 buys, fees is 10 for buy/sell
/// then switch to normal 5 percent on buy/sell
if(buyCount > 5){
feeDiv = initialFee;
} else {
feeDiv = midFee;
}
if(takeFee){
if(isAutomatedMarketMaker[from] && totalBuyFee > 0){
if(buyCount > 0){
buyCount = buyCount - 1;
fees = (amount * feeDiv) / 100;
} else {
fees = (amount * totalBuyFee) / 100;
}
}
if(isAutomatedMarketMaker[to] && totalSellFee > 0){
if(buyCount > 0){
fees = (amount * feeDiv) / 100;
} else {
fees = (amount * totalSellFee) / 100;
}
}
super._transfer(from, address(this), fees);
amount = amount - fees;
}
super._transfer(from, to, amount);
}
/// @notice swap the collected fees to eth / add liquidity
/// after conversion, it sends eth to marketing wallet, add auto liquidity
/// @param tokenAmount: tokens to be swapped appropriately as per fee structure
function swapAndLiquify (uint256 tokenAmount) private lockTheSwap {
if(totalBuyFee + totalSellFee == 0){
swapTokensForEth(tokenAmount);
bool m;
(m,) = payable(marketingWallet).call{value: address(this).balance}("");
} else {
uint256 marketingTokens = ((buyFee.marketing + sellFee.marketing) * tokenAmount) / (totalBuyFee + totalSellFee);
uint256 liquidityTokens = tokenAmount - marketingTokens;
uint256 liquidityTokensHalf = liquidityTokens / 2;
uint256 swapTokens = tokenAmount - liquidityTokensHalf;
uint256 ethBalanceBeforeSwap = address(this).balance;
swapTokensForEth(swapTokens);
uint256 ethBalanceAfterSwap = address(this).balance - ethBalanceBeforeSwap;
uint256 ethForLiquidity = (liquidityTokensHalf * ethBalanceAfterSwap) /swapTokens;
if(ethForLiquidity > 0 && liquidityTokensHalf > 0){
addLiquidity(liquidityTokensHalf, ethForLiquidity);
}
bool success;
uint256 marketingEth = address(this).balance;
if(marketingEth > 0){
(success,) = payable(marketingWallet).call{value: marketingEth}("");
}
emit FeesSwapped(ethForLiquidity, liquidityTokensHalf, marketingEth);
}
}
/// @notice manages tokens conversion to eth
/// @param tokenAmount: tokens to be converted to eth
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();
if(allowance(address(this), address(uniswapV2Router)) < tokenAmount){
_approve(address(this), address(uniswapV2Router), type(uint256).max);
}
// make the swap
uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0, // accept any amount of ETH
path,
address(this),
block.timestamp
);
}
/// @notice manage autoLP (liquidity addition)
/// @param tokenAmount: tokens to be added to liquidity
/// @param ethAmount: eth to be added to liquidity
function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
// add the liquidity
uniswapV2Router.addLiquidityETH{value: ethAmount}(
address(this),
tokenAmount,
0, // slippage is unavoidable
0, // slippage is unavoidable
owner(), // LP tokens recevier
block.timestamp
);
}
/// @notice convert all or some percentage of collected tax to eth
/// @param percentage: percentage of collected tax to swap
function manualSwap (uint256 percentage) external lockTheSwap{
if(msg.sender != marketingWallet){
revert OnlyMarketingWalletAllowed();
}
uint256 tokens = balanceOf(address(this));
uint256 amount = (tokens * percentage) / 100;
swapTokensForEth(amount);
uint256 ethAmount = address(this).balance;
bool success;
(success,) = payable(marketingWallet).call{value: ethAmount}("");
}
}
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 v4.9.0) (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].
*
* The default value of {decimals} is 18. To change this, you should override
* this function so it returns a different value.
*
* 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}.
*
* 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 default value returned by this function, unless
* it's 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 v4.9.0) (access/Ownable2Step.sol)
pragma solidity ^0.8.0;
import "./Ownable.sol";
/**
* @dev Contract module which provides 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} and {acceptOwnership}.
*
* This module is used through inheritance. It will make available all functions
* from parent (Ownable).
*/
abstract contract Ownable2Step is Ownable {
address private _pendingOwner;
event OwnershipTransferStarted(address indexed previousOwner, address indexed newOwner);
/**
* @dev Returns the address of the pending owner.
*/
function pendingOwner() public view virtual returns (address) {
return _pendingOwner;
}
/**
* @dev Starts the ownership transfer of the contract to a new account. Replaces the pending transfer if there is one.
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual override onlyOwner {
_pendingOwner = newOwner;
emit OwnershipTransferStarted(owner(), newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`) and deletes any pending owner.
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual override {
delete _pendingOwner;
super._transferOwnership(newOwner);
}
/**
* @dev The new owner accepts the ownership transfer.
*/
function acceptOwnership() public virtual {
address sender = _msgSender();
require(pendingOwner() == sender, "Ownable2Step: caller is not the new owner");
_transferOwnership(sender);
}
}
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 v4.9.0) (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);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (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. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling 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);
}
}