Contract Name:
RocketRaffle
Contract Source Code:
pragma solidity >=0.8.10 >=0.8.0 <0.9.0;
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol";
import "@chainlink/contracts/src/v0.8/interfaces/VRFCoordinatorV2Interface.sol";
import "@chainlink/contracts/src/v0.8/VRFConsumerBaseV2.sol";
//Rocket Raffle Contract
contract RocketRaffle is VRFConsumerBaseV2, Ownable {
using SafeMath for uint256;
VRFCoordinatorV2Interface COORDINATOR;
//VRF values
uint64 s_subscriptionId;
address vrfCoordinator = 0x271682DEB8C4E0901D1a1550aD2e64D568E69909;
bytes32 keyHash = 0x8af398995b04c28e9951adb9721ef74c74f93e6a478f39e7e0777be13527e7ef;
uint32 callbackGasLimit = 1000000;
uint16 requestConfirmations = 3;
uint32 numWords = 1;
uint256 public s_requestId;
//Game Values
enum RAFFLE_STATE { OPEN, CLOSED, CALCULATING_WINNER }
RAFFLE_STATE public raffle_state;
address payable[] public players;
uint256 public raffleId;
uint public raffleStartDate;
uint public raffleEndDate;
uint256 ticketCostRKTN = 10_000 * 1e18;
uint256 ticketCostRKFL = 100_000 * 1e18;
uint256 MaxRaffleAmount = 5 *1e18;
//Player info
struct player{
uint256 ticketsBought;
uint256 gamesWon;
}
mapping(address => player) public playerStats;
//events
event RaffleOpen(uint256 _raffleId);
event RaffleClose(uint256 _raffleId);
event RaffleWinner(
uint256 _raffleId,
uint256 _randomness,
uint256 _index,
address indexed _from,
uint256 _amount
);
event PlayerJoined(uint256 _raffleId, address indexed _from);
event TicketsRewarded(address _address, uint256 _amountRewarded);
//Rocket Token and Rocket Fuel
IUniswapV2Router02 public immutable uniswapV2Router;
IERC20 rocketToken;
IERC20 rocketFuel;
//modifier to check state of game
modifier atState(RAFFLE_STATE _state) {
require(raffle_state == _state, "Function cannot be called at this time.");
_;
}
//constructor
constructor(uint64 subscriptionId, address _rocketToken, address _rocketFuel) VRFConsumerBaseV2(vrfCoordinator) {
IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
uniswapV2Router = _uniswapV2Router;
COORDINATOR = VRFCoordinatorV2Interface(vrfCoordinator);
s_subscriptionId = subscriptionId;
raffleId = 1;
raffle_state = RAFFLE_STATE.CLOSED;
rocketToken = IERC20(_rocketToken);
rocketFuel = IERC20(_rocketFuel);
}
receive() external payable {}
function setethRaffleMaxWin(uint256 _eth) public onlyOwner{
require(_eth*1e18 > 1 *1e18, "max winner must be bigger than 1 eth");
MaxRaffleAmount = _eth *1e18;
}
function setethRaffleTicketPriceRKTN(uint256 ticketPrice) public onlyOwner{
uint256 totalSuypply = rocketToken.totalSupply();
require(ticketPrice < ( totalSuypply* 5) / 1000, "Set a reasonable price ticket cost has to be lower then .5%");
ticketCostRKTN = ticketPrice;
}
function setethRaffleTicketPriceRKFL(uint256 ticketPrice) public onlyOwner{
uint256 totalSuypply = rocketFuel.totalSupply();
require(ticketPrice < ( totalSuypply* 5) / 1000, "Set a reasonable price ticket cost has to be lower then .5%");
ticketCostRKFL = ticketPrice;
}
function starRaffle() public onlyOwner {
require(raffle_state == RAFFLE_STATE.CLOSED, "can't start a new raffle yet");
players = new address payable[](0);
raffleStartDate = block.timestamp;
raffle_state = RAFFLE_STATE.OPEN;
emit RaffleOpen(raffleId);
}
function getAmountOfTicketsOwned(address _address) public view returns(uint256 amountOfTickets){
uint256 amount = players.length;
uint256 tickets = 0;
for (uint i=0; i < amount; i++) {
if(players[i] == _address){
tickets += 1;
}
}
return tickets;
}
function getTotalTicketsPurchased() public view returns(uint256 amountOfTickets){
uint256 amount = players.length;
return amount;
}
function getWinnings() public view returns(uint256 winnings){
uint256 contractBalance = address(this).balance;
if(contractBalance < MaxRaffleAmount){
return (contractBalance / 2);
}
else {
return MaxRaffleAmount;
}
}
//calls chainlink vrf to select winner of raffle
function PickWinner() public onlyOwner {
require(raffle_state == RAFFLE_STATE.OPEN);
raffle_state = RAFFLE_STATE.CALCULATING_WINNER;
requestRandomWords();
}
//for upgrading raffle contract or emergency
function Withdraw() public onlyOwner{
bool success;
(success, ) = address(msg.sender).call{value: address(this).balance}("");
}
//reward up to 10 raffle tickets
function rewardTickets(address _address, uint256 _amount) public onlyOwner {
require(_amount <= 10, "cannot rewrd more than 10 tickets");
for (uint i=1; i <= _amount; i++) {
players.push(payable(_address));
playerStats[_address].ticketsBought +=1;
}
emit TicketsRewarded(_address, _amount);
}
//buy raffle tickets
function buyTickets(uint256 numberOfTickets, uint256 _token) public payable atState(RAFFLE_STATE.OPEN) {
require(_token == 0 || _token == 1, "invalid token selection");
if(_token == 0){
uint256 balance = rocketToken.balanceOf(msg.sender);
uint256 amount = ticketCostRKTN * numberOfTickets;
require(balance >= amount, "You must pay the proper amount for ticket");
uint256 allowance = rocketToken.allowance(msg.sender, address(this));
require(allowance >= amount, "Check token allowance");
rocketToken.transferFrom(msg.sender, address(0xdead), amount);
}
else if(_token == 1){
uint256 balance = rocketFuel.balanceOf(msg.sender);
uint256 amount = ticketCostRKFL * numberOfTickets;
require(balance >= amount, "You must pay the proper amount for ticket");
uint256 allowance = rocketFuel.allowance(msg.sender, address(this));
require(allowance >= amount, "Check token allowance");
rocketFuel.transferFrom(msg.sender, address(0xdead), amount);
}
//add player and set info
for (uint i=1; i <= numberOfTickets; i++) {
players.push(payable(msg.sender));
playerStats[msg.sender].ticketsBought +=1;
}
emit PlayerJoined(raffleId, msg.sender);
}
//buy back RKTN with 10% of raffle winnings
function swapEthForTokens(address token, uint256 ethAmount) private {
// generate the uniswap pair path of weth -> token
address[] memory path = new address[](2);
path[0] = uniswapV2Router.WETH();
path[1] = token;
// make the swap
uniswapV2Router.swapExactETHForTokensSupportingFeeOnTransferTokens{value: ethAmount}(
0,
path,
address(this),
block.timestamp
);
}
function BuyBack() private{
uint256 amount = getWinnings() * 10 / 100;
swapEthForTokens(address(rocketToken), amount / 2);
uint256 rocketTokenBalance = rocketToken.balanceOf(address(this));
rocketToken.transfer(address(0xdead), rocketTokenBalance);
}
//gets random number
function requestRandomWords() private {
// Will revert if subscription is not set and funded.
s_requestId = COORDINATOR.requestRandomWords(
keyHash,
s_subscriptionId,
requestConfirmations,
callbackGasLimit,
numWords
);
}
//pays winner closes game and does buyback
function fulfillRandomWords(
uint256, /* requestId */
uint256[] memory randomWords
) internal override {
//pick winner
uint256 index = randomWords[0] % players.length;
uint256 winnings = getWinnings() * 90 / 100;
BuyBack();
address winner = players[index];
//pay winner
bool success;
(success, ) = address(winner).call{value: winnings}("");
raffle_state = RAFFLE_STATE.CLOSED;
emit RaffleWinner(raffleId, randomWords[0], index, winner, winnings);
emit RaffleClose(raffleId);
raffleId = raffleId + 1;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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.zeppelin.solutions/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 `sender` to `recipient`.
*
* 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;
}
_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;
_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;
}
_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 v4.4.1 (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 Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
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);
}
}
// 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;
}
}
}
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;
}
pragma solidity >=0.5.0;
interface IUniswapV2Pair {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);
function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint);
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
event Mint(address indexed sender, uint amount0, uint amount1);
event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
event Swap(
address indexed sender,
uint amount0In,
uint amount1In,
uint amount0Out,
uint amount1Out,
address indexed to
);
event Sync(uint112 reserve0, uint112 reserve1);
function MINIMUM_LIQUIDITY() external pure returns (uint);
function factory() external view returns (address);
function token0() external view returns (address);
function token1() external view returns (address);
function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
function price0CumulativeLast() external view returns (uint);
function price1CumulativeLast() external view returns (uint);
function kLast() external view returns (uint);
function mint(address to) external returns (uint liquidity);
function burn(address to) external returns (uint amount0, uint amount1);
function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
function skim(address to) external;
function sync() external;
function initialize(address, address) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface VRFCoordinatorV2Interface {
/**
* @notice Get configuration relevant for making requests
* @return minimumRequestConfirmations global min for request confirmations
* @return maxGasLimit global max for request gas limit
* @return s_provingKeyHashes list of registered key hashes
*/
function getRequestConfig()
external
view
returns (
uint16,
uint32,
bytes32[] memory
);
/**
* @notice Request a set of random words.
* @param keyHash - Corresponds to a particular oracle job which uses
* that key for generating the VRF proof. Different keyHash's have different gas price
* ceilings, so you can select a specific one to bound your maximum per request cost.
* @param subId - The ID of the VRF subscription. Must be funded
* with the minimum subscription balance required for the selected keyHash.
* @param minimumRequestConfirmations - How many blocks you'd like the
* oracle to wait before responding to the request. See SECURITY CONSIDERATIONS
* for why you may want to request more. The acceptable range is
* [minimumRequestBlockConfirmations, 200].
* @param callbackGasLimit - How much gas you'd like to receive in your
* fulfillRandomWords callback. Note that gasleft() inside fulfillRandomWords
* may be slightly less than this amount because of gas used calling the function
* (argument decoding etc.), so you may need to request slightly more than you expect
* to have inside fulfillRandomWords. The acceptable range is
* [0, maxGasLimit]
* @param numWords - The number of uint256 random values you'd like to receive
* in your fulfillRandomWords callback. Note these numbers are expanded in a
* secure way by the VRFCoordinator from a single random value supplied by the oracle.
* @return requestId - A unique identifier of the request. Can be used to match
* a request to a response in fulfillRandomWords.
*/
function requestRandomWords(
bytes32 keyHash,
uint64 subId,
uint16 minimumRequestConfirmations,
uint32 callbackGasLimit,
uint32 numWords
) external returns (uint256 requestId);
/**
* @notice Create a VRF subscription.
* @return subId - A unique subscription id.
* @dev You can manage the consumer set dynamically with addConsumer/removeConsumer.
* @dev Note to fund the subscription, use transferAndCall. For example
* @dev LINKTOKEN.transferAndCall(
* @dev address(COORDINATOR),
* @dev amount,
* @dev abi.encode(subId));
*/
function createSubscription() external returns (uint64 subId);
/**
* @notice Get a VRF subscription.
* @param subId - ID of the subscription
* @return balance - LINK balance of the subscription in juels.
* @return reqCount - number of requests for this subscription, determines fee tier.
* @return owner - owner of the subscription.
* @return consumers - list of consumer address which are able to use this subscription.
*/
function getSubscription(uint64 subId)
external
view
returns (
uint96 balance,
uint64 reqCount,
address owner,
address[] memory consumers
);
/**
* @notice Request subscription owner transfer.
* @param subId - ID of the subscription
* @param newOwner - proposed new owner of the subscription
*/
function requestSubscriptionOwnerTransfer(uint64 subId, address newOwner) external;
/**
* @notice Request subscription owner transfer.
* @param subId - ID of the subscription
* @dev will revert if original owner of subId has
* not requested that msg.sender become the new owner.
*/
function acceptSubscriptionOwnerTransfer(uint64 subId) external;
/**
* @notice Add a consumer to a VRF subscription.
* @param subId - ID of the subscription
* @param consumer - New consumer which can use the subscription
*/
function addConsumer(uint64 subId, address consumer) external;
/**
* @notice Remove a consumer from a VRF subscription.
* @param subId - ID of the subscription
* @param consumer - Consumer to remove from the subscription
*/
function removeConsumer(uint64 subId, address consumer) external;
/**
* @notice Cancel a subscription
* @param subId - ID of the subscription
* @param to - Where to send the remaining LINK to
*/
function cancelSubscription(uint64 subId, address to) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;
/** ****************************************************************************
* @notice Interface for contracts using VRF randomness
* *****************************************************************************
* @dev PURPOSE
*
* @dev Reggie the Random Oracle (not his real job) wants to provide randomness
* @dev to Vera the verifier in such a way that Vera can be sure he's not
* @dev making his output up to suit himself. Reggie provides Vera a public key
* @dev to which he knows the secret key. Each time Vera provides a seed to
* @dev Reggie, he gives back a value which is computed completely
* @dev deterministically from the seed and the secret key.
*
* @dev Reggie provides a proof by which Vera can verify that the output was
* @dev correctly computed once Reggie tells it to her, but without that proof,
* @dev the output is indistinguishable to her from a uniform random sample
* @dev from the output space.
*
* @dev The purpose of this contract is to make it easy for unrelated contracts
* @dev to talk to Vera the verifier about the work Reggie is doing, to provide
* @dev simple access to a verifiable source of randomness. It ensures 2 things:
* @dev 1. The fulfillment came from the VRFCoordinator
* @dev 2. The consumer contract implements fulfillRandomWords.
* *****************************************************************************
* @dev USAGE
*
* @dev Calling contracts must inherit from VRFConsumerBase, and can
* @dev initialize VRFConsumerBase's attributes in their constructor as
* @dev shown:
*
* @dev contract VRFConsumer {
* @dev constructor(<other arguments>, address _vrfCoordinator, address _link)
* @dev VRFConsumerBase(_vrfCoordinator) public {
* @dev <initialization with other arguments goes here>
* @dev }
* @dev }
*
* @dev The oracle will have given you an ID for the VRF keypair they have
* @dev committed to (let's call it keyHash). Create subscription, fund it
* @dev and your consumer contract as a consumer of it (see VRFCoordinatorInterface
* @dev subscription management functions).
* @dev Call requestRandomWords(keyHash, subId, minimumRequestConfirmations,
* @dev callbackGasLimit, numWords),
* @dev see (VRFCoordinatorInterface for a description of the arguments).
*
* @dev Once the VRFCoordinator has received and validated the oracle's response
* @dev to your request, it will call your contract's fulfillRandomWords method.
*
* @dev The randomness argument to fulfillRandomWords is a set of random words
* @dev generated from your requestId and the blockHash of the request.
*
* @dev If your contract could have concurrent requests open, you can use the
* @dev requestId returned from requestRandomWords to track which response is associated
* @dev with which randomness request.
* @dev See "SECURITY CONSIDERATIONS" for principles to keep in mind,
* @dev if your contract could have multiple requests in flight simultaneously.
*
* @dev Colliding `requestId`s are cryptographically impossible as long as seeds
* @dev differ.
*
* *****************************************************************************
* @dev SECURITY CONSIDERATIONS
*
* @dev A method with the ability to call your fulfillRandomness method directly
* @dev could spoof a VRF response with any random value, so it's critical that
* @dev it cannot be directly called by anything other than this base contract
* @dev (specifically, by the VRFConsumerBase.rawFulfillRandomness method).
*
* @dev For your users to trust that your contract's random behavior is free
* @dev from malicious interference, it's best if you can write it so that all
* @dev behaviors implied by a VRF response are executed *during* your
* @dev fulfillRandomness method. If your contract must store the response (or
* @dev anything derived from it) and use it later, you must ensure that any
* @dev user-significant behavior which depends on that stored value cannot be
* @dev manipulated by a subsequent VRF request.
*
* @dev Similarly, both miners and the VRF oracle itself have some influence
* @dev over the order in which VRF responses appear on the blockchain, so if
* @dev your contract could have multiple VRF requests in flight simultaneously,
* @dev you must ensure that the order in which the VRF responses arrive cannot
* @dev be used to manipulate your contract's user-significant behavior.
*
* @dev Since the block hash of the block which contains the requestRandomness
* @dev call is mixed into the input to the VRF *last*, a sufficiently powerful
* @dev miner could, in principle, fork the blockchain to evict the block
* @dev containing the request, forcing the request to be included in a
* @dev different block with a different hash, and therefore a different input
* @dev to the VRF. However, such an attack would incur a substantial economic
* @dev cost. This cost scales with the number of blocks the VRF oracle waits
* @dev until it calls responds to a request. It is for this reason that
* @dev that you can signal to an oracle you'd like them to wait longer before
* @dev responding to the request (however this is not enforced in the contract
* @dev and so remains effective only in the case of unmodified oracle software).
*/
abstract contract VRFConsumerBaseV2 {
error OnlyCoordinatorCanFulfill(address have, address want);
address private immutable vrfCoordinator;
/**
* @param _vrfCoordinator address of VRFCoordinator contract
*/
constructor(address _vrfCoordinator) {
vrfCoordinator = _vrfCoordinator;
}
/**
* @notice fulfillRandomness handles the VRF response. Your contract must
* @notice implement it. See "SECURITY CONSIDERATIONS" above for important
* @notice principles to keep in mind when implementing your fulfillRandomness
* @notice method.
*
* @dev VRFConsumerBaseV2 expects its subcontracts to have a method with this
* @dev signature, and will call it once it has verified the proof
* @dev associated with the randomness. (It is triggered via a call to
* @dev rawFulfillRandomness, below.)
*
* @param requestId The Id initially returned by requestRandomness
* @param randomWords the VRF output expanded to the requested number of words
*/
function fulfillRandomWords(uint256 requestId, uint256[] memory randomWords) internal virtual;
// rawFulfillRandomness is called by VRFCoordinator when it receives a valid VRF
// proof. rawFulfillRandomness then calls fulfillRandomness, after validating
// the origin of the call
function rawFulfillRandomWords(uint256 requestId, uint256[] memory randomWords) external {
if (msg.sender != vrfCoordinator) {
revert OnlyCoordinatorCanFulfill(msg.sender, vrfCoordinator);
}
fulfillRandomWords(requestId, randomWords);
}
}
// 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);
}
// 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 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;
}
}
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);
}