// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
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);
}
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
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);
}
}
contract TCASHStaking is Ownable {
IERC20 public TCASHToken; // TCASH token address
uint256 public developmentFeeRate = 5; // 5% development fee rate
uint256 public durationForMinimumReward = 2 minutes; // staking period at least
uint256 public stakingStartTime; // First staked time in this contract
uint256 public nStakers; // Number of users
struct Stake {
uint256 stakedAmount;
uint256 removingAmount;
uint256 stakedTime;
}
mapping(address => Stake) public stakes;
address public developmentFee; // Development fee address
address public stakedInfo; // Contract StakedInfo getting address
event Staked(address indexed user, uint256 stakedAmount);
event Unstaked(address indexed user, uint256 unstakedAmount, uint256 earnedETHRewards);
constructor (
address _TCASHToken,
address _stakedInfo,
address _developmentFee
) {
TCASHToken = IERC20(_TCASHToken);
stakedInfo = _stakedInfo;
developmentFee = _developmentFee;
stakingStartTime = block.timestamp;
nStakers = 0;
}
// To get ETH into the contract
receive() external payable {}
fallback() external payable {}
// Stake TCASH tokens
function stake(uint256 amount) external {
require(amount > 0, "Amount must be greater than zero");
// Stake TCASH token to this contract
require(TCASHToken.transferFrom(msg.sender, address(this), amount), "Transfer failed");
if(stakes[msg.sender].stakedTime != 0) {
stakes[stakedInfo].stakedAmount += amount;
stakes[stakedInfo].removingAmount += (block.timestamp - stakingStartTime) * amount;
stakes[msg.sender].stakedAmount += amount;
stakes[msg.sender].removingAmount += (block.timestamp - stakingStartTime) * amount;
} else {
stakes[stakedInfo].stakedAmount += amount;
stakes[stakedInfo].removingAmount += (block.timestamp - stakingStartTime) * amount;
stakes[msg.sender] = Stake(amount, (block.timestamp - stakingStartTime) * amount, block.timestamp);
nStakers++;
}
emit Staked(msg.sender, stakes[msg.sender].stakedAmount);
}
// Unstake TCASH tokens
function unstake() external {
require(stakes[msg.sender].stakedAmount > 0, "No staked amount");
uint256 stakingDuration = block.timestamp - stakes[msg.sender].stakedTime;
uint256 earnedETHRewards = 0;
uint256 realEarnedETHRewards = 0;
uint256 developmentFeeETHRewards = 0;
uint256 totalETHAmountsInContract = address(this).balance;
if (stakingDuration < durationForMinimumReward) {
require(TCASHToken.transfer(msg.sender, stakes[msg.sender].stakedAmount), "Transfer TCASH token failed");
stakes[stakedInfo].stakedAmount -= stakes[msg.sender].stakedAmount;
stakes[stakedInfo].removingAmount -= stakes[msg.sender].removingAmount;
nStakers--;
stakes[msg.sender].stakedAmount = 0;
stakes[msg.sender].removingAmount = 0;
stakes[msg.sender].stakedTime = 0;
} else {
earnedETHRewards = (stakes[msg.sender].stakedAmount * (block.timestamp - stakingStartTime) - stakes[msg.sender].removingAmount) * totalETHAmountsInContract / (stakes[stakedInfo].stakedAmount * (block.timestamp - stakingStartTime) - stakes[stakedInfo].removingAmount);
require(TCASHToken.transfer(msg.sender, stakes[msg.sender].stakedAmount), "Transfer TCASH token failed");
stakes[stakedInfo].stakedAmount -= stakes[msg.sender].stakedAmount;
stakes[stakedInfo].removingAmount -= stakes[msg.sender].removingAmount;
nStakers--;
stakes[msg.sender].stakedAmount = 0;
stakes[msg.sender].removingAmount = 0;
stakes[msg.sender].stakedTime = 0;
//Transfer ETH
if(earnedETHRewards > 0)
{
// Transfer ETH Reward to developer
developmentFeeETHRewards = earnedETHRewards * developmentFeeRate / 100;
payable(developmentFee).transfer(developmentFeeETHRewards);
// Transfer ETH Reward to user
realEarnedETHRewards = earnedETHRewards - developmentFeeETHRewards;
payable(msg.sender).transfer(realEarnedETHRewards);
}
}
emit Unstaked(msg.sender, stakes[msg.sender].stakedAmount, realEarnedETHRewards);
}
// Owner function to manually set staking period
function manualSetStakingPeriod(uint256 amount) external onlyOwner {
durationForMinimumReward = amount;
}
// Owner function to manually set development Fee address
function manualSetDevelopmentFee(address developmentFeeAddress) external onlyOwner {
developmentFee = developmentFeeAddress;
}
// Owner function to manually set development Fee Rate
function manualSetDevelopmentFeeRate(uint256 devFeeRate) external onlyOwner {
developmentFeeRate = devFeeRate;
}
}
{
"compilationTarget": {
"TCASHStaking.sol": "TCASHStaking"
},
"evmVersion": "cancun",
"libraries": {},
"metadata": {
"bytecodeHash": "ipfs"
},
"optimizer": {
"enabled": true,
"runs": 200
},
"remappings": []
}
[{"inputs":[{"internalType":"address","name":"_TCASHToken","type":"address"},{"internalType":"address","name":"_stakedInfo","type":"address"},{"internalType":"address","name":"_developmentFee","type":"address"}],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"user","type":"address"},{"indexed":false,"internalType":"uint256","name":"stakedAmount","type":"uint256"}],"name":"Staked","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"user","type":"address"},{"indexed":false,"internalType":"uint256","name":"unstakedAmount","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"earnedETHRewards","type":"uint256"}],"name":"Unstaked","type":"event"},{"stateMutability":"payable","type":"fallback"},{"inputs":[],"name":"TCASHToken","outputs":[{"internalType":"contract IERC20","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"developmentFee","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"developmentFeeRate","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"durationForMinimumReward","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"developmentFeeAddress","type":"address"}],"name":"manualSetDevelopmentFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"devFeeRate","type":"uint256"}],"name":"manualSetDevelopmentFeeRate","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"manualSetStakingPeriod","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"nStakers","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"stake","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"stakedInfo","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"","type":"address"}],"name":"stakes","outputs":[{"internalType":"uint256","name":"stakedAmount","type":"uint256"},{"internalType":"uint256","name":"removingAmount","type":"uint256"},{"internalType":"uint256","name":"stakedTime","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"stakingStartTime","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"unstake","outputs":[],"stateMutability":"nonpayable","type":"function"},{"stateMutability":"payable","type":"receive"}]