Contract Source Code:
// 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);
}
}
// 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 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
pragma solidity ^0.8.20;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
contract FrogsSale is Ownable {
IERC20 public saleToken; // Token to be distributed
struct ReferralData {
uint256 totalContribution;
uint256 totalReferrals;
}
uint256 public constant MAX_POOL = 500000 ether; // 500,000 CRO
uint256 public constant INDIVIDUAL_CAP = 5000 ether; // 5,000 CRO
uint256 public constant SALE_TOKEN_SUPPLY = 1000000000 * 10**18; // 1,000,000,000 FROGS with 18 decimals
mapping(address => uint256) public contributions; // Tracks contributions per user
mapping(address => address) public referrals; // Tracks user referrals
mapping(address => uint256) public totalReferralEarned; // Tracks total referral rewards earned per user
mapping(address => ReferralData) public referralData; // Tracks total contributions made by referrals
uint256 public totalContributed; // Total CRO contributed
bool public isSaleActive = true;
uint256 public startTime; // Sale start time
uint256 public endTime; // Sale end time
uint256 public referralPercentage = 2; // Default 2% referral reward
event Contribution(address indexed user, uint256 amount, address indexed referral);
event TokensClaimed(address indexed user, uint256 tokenAmount, uint256 croRefunded, uint256 referralReward);
event SaleClosed();
event SaleTimesUpdated(uint256 startTime, uint256 endTime);
event ReferralPercentageUpdated(uint256 newPercentage);
constructor(IERC20 _saleToken) {
saleToken = _saleToken;
}
/**
* @dev Allows users to claim tokens, refunds excess CRO, and allocates referral rewards.
*/
function claimTokens() external {
require(!isSaleActive, "Sale is still active");
require(block.timestamp > endTime, "Sale has not ended yet");
require(contributions[msg.sender] > 0, "No contributions to claim tokens");
uint256 userContribution = contributions[msg.sender];
uint256 totalTokens = SALE_TOKEN_SUPPLY;
uint256 tokenAmount = (userContribution * totalTokens) / totalContributed;
uint256 excessCRO = userContribution > (userContribution * MAX_POOL / totalContributed)
? userContribution - (userContribution * MAX_POOL / totalContributed)
: 0;
// Calculate referral reward for the user
uint256 referralReward = (referralData[msg.sender].totalContribution * totalTokens / totalContributed)
* referralPercentage / 100;
totalReferralEarned[msg.sender] += referralReward;
// Reset user contribution
contributions[msg.sender] = 0;
// Transfer tokens (main + referral rewards) to the user
saleToken.transfer(msg.sender, tokenAmount + referralReward);
// Refund excess CRO
if (excessCRO > 0) {
payable(msg.sender).transfer(excessCRO);
}
emit TokensClaimed(msg.sender, tokenAmount, excessCRO, referralReward);
}
/**
* @dev Allows users to estimate their token allocation, excess CRO, and referral rewards.
*/
function estimateClaim(address user) external view returns (uint256 tokenAmount, uint256 excessCRO, uint256 referralReward) {
if (totalContributed == 0 || contributions[user] == 0) {
return (0, 0, 0);
}
uint256 userContribution = contributions[user];
uint256 totalTokens = SALE_TOKEN_SUPPLY;
tokenAmount = (userContribution * totalTokens) / totalContributed;
excessCRO = userContribution > (userContribution * MAX_POOL / totalContributed)
? userContribution - (userContribution * MAX_POOL / totalContributed)
: 0;
referralReward = (referralData[user].totalContribution * totalTokens / totalContributed) * referralPercentage / 100;
}
/**
* @dev Withdraw collected CRO up to the MAX_POOL limit.
*/
function withdrawCRO() external onlyOwner {
uint256 amount = address(this).balance > MAX_POOL ? MAX_POOL : address(this).balance;
payable(owner()).transfer(amount);
}
/**
* @dev Withdraw unsold tokens proportional to the uncollected CRO.
*/
function withdrawUnsoldTokens() external onlyOwner {
uint256 soldTokens = (totalContributed * SALE_TOKEN_SUPPLY) / MAX_POOL;
uint256 unsoldTokens = SALE_TOKEN_SUPPLY - soldTokens;
require(unsoldTokens > 0, "No unsold tokens available");
saleToken.transfer(owner(), unsoldTokens);
}
/**
* @dev Allows users to contribute CRO to the sale with an optional referral.
*/
function contribute(address referral) external payable {
require(isSaleActive, "Sale is not active");
require(block.timestamp >= startTime, "Sale has not started yet");
require(block.timestamp <= endTime, "Sale has ended");
require(msg.value > 0, "Contribution must be > 0");
require(contributions[msg.sender] + msg.value <= INDIVIDUAL_CAP, "Exceeds individual cap");
uint256 contribution = msg.value;
contributions[msg.sender] += contribution;
totalContributed += contribution;
// Record referral
if (referral != address(0) && referral != msg.sender && referrals[msg.sender] == address(0)) {
referrals[msg.sender] = referral;
referralData[referral].totalReferrals += 1;
referralData[referral].totalContribution += contribution;
} else if (referrals[msg.sender] != address(0)) {
referralData[referrals[msg.sender]].totalContribution += contribution;
}
emit Contribution(msg.sender, contribution, referral);
}
/**
* @dev Allows the owner to close the sale.
*/
function closeSale() external onlyOwner {
require(isSaleActive, "Sale already closed");
isSaleActive = false;
emit SaleClosed();
}
/**
* @dev Sets the start and end time for the sale.
*/
function setSaleTimes(uint256 _startTime, uint256 _endTime) external onlyOwner {
require(_startTime < _endTime, "Start time must be before end time");
startTime = _startTime;
endTime = _endTime;
emit SaleTimesUpdated(startTime, endTime);
}
/**
* @dev Allows the owner to set the referral reward percentage.
*/
function setReferralPercentage(uint256 _percentage) external onlyOwner {
require(_percentage <= 10, "Referral percentage too high");
referralPercentage = _percentage;
emit ReferralPercentageUpdated(_percentage);
}
}