文件 1 的 1:BCUGFarm.sol
pragma solidity ^0.8.0;
library SafeMath {
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, 'SafeMath: addition overflow');
return c;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, 'SafeMath: subtraction overflow');
uint256 c = a - b;
return c;
}
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, 'SafeMath: multiplication overflow');
return c;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0, 'SafeMath: division by zero');
uint256 c = a / b;
return c;
}
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0, 'SafeMath: modulo by zero');
return a % b;
}
}
library Math {
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return a >= b ? a : b;
}
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
function average(uint256 a, uint256 b) internal pure returns (uint256) {
return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
}
}
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
this;
return msg.data;
}
}
contract Ownable is Context {
address private _owner;
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
constructor() {
_owner = _msgSender();
emit OwnershipTransferred(address(0), _owner);
}
function owner() public view returns (address) {
return _owner;
}
modifier onlyOwner() {
require(isOwner(), 'Ownable: caller is not the owner');
_;
}
function isOwner() public view returns (bool) {
return _msgSender() == _owner;
}
function renounceOwnership() public onlyOwner {
emit OwnershipTransferred(
_owner,
address(0x0)
);
_owner = address(0x0);
}
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
function _transferOwnership(address newOwner) internal {
require(
newOwner != address(0x0),
'Ownable: new owner is the zero address'
);
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address recipient, uint256 amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
library Address {
function isContract(address account) internal view returns (bool) {
uint256 size;
assembly {
size := extcodesize(account)
}
return size > 0;
}
}
library SafeERC20 {
using SafeMath for uint256;
using Address for address;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
callOptionalReturn(
token,
abi.encodeWithSelector(
token.transfer.selector,
to,
value
)
);
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
callOptionalReturn(
token,
abi.encodeWithSelector(
token.transferFrom.selector,
from,
to,
value
)
);
}
function safeApprove(IERC20 token, address spender, uint256 value) internal {
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
'SafeERC20: approve from non-zero to non-zero allowance'
);
callOptionalReturn(
token,
abi.encodeWithSelector(
token.approve.selector,
spender,
value
)
);
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).add(value);
callOptionalReturn(
token,
abi.encodeWithSelector(
token.approve.selector,
spender,
newAllowance
)
);
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(value);
callOptionalReturn(
token,
abi.encodeWithSelector(
token.approve.selector,
spender,
newAllowance
)
);
}
function callOptionalReturn(IERC20 token, bytes memory data) private {
require(address(token).isContract(), 'SafeERC20: call to non-contract');
(bool success, bytes memory returndata) = address(token).call(data);
require(success, 'SafeERC20: low-level call failed');
if (returndata.length > 0) {
require(abi.decode(returndata, (bool)), 'SafeERC20: ERC20 operation did not succeed');
}
}
}
contract LPTokenWrapper {
using SafeMath for uint256;
using SafeERC20 for IERC20;
IERC20 public lp = IERC20(0x8382AeaB50c5d60e06cf3B68A51Cd88C39A061c6);
uint256 private _totalSupply;
mapping(address => uint256) private _balances;
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
function balanceOf(address account) public view returns (uint256) {
return _balances[account];
}
function _stake(uint256 amount) internal {
_totalSupply = _totalSupply.add(amount);
_balances[msg.sender] =
_balances[msg.sender].add(amount);
lp.safeTransferFrom(msg.sender, address(this), amount);
}
function _withdraw(uint256 amount) internal {
_totalSupply = _totalSupply.sub(amount);
_balances[msg.sender] =
_balances[msg.sender].sub(amount);
lp.safeTransfer(msg.sender, amount);
}
}
contract BCUGFarm is LPTokenWrapper, Ownable {
using SafeMath for uint256;
using SafeERC20 for IERC20;
IERC20 public bcug = IERC20(0x14Da7b27b2E0FedEfe0a664118b0c9bc68e2E9AF);
uint256 public constant DURATION = 4 weeks;
uint256 public periodFinish;
uint256 public rewardRate;
uint256 public lastUpdateTime;
uint256 public rewardPerTokenStored;
mapping(address => uint256) public userRewardPerTokenPaid;
mapping(address => uint256) public rewards;
event RewardAdded(uint256 reward);
event Staked(address indexed user, uint256 amount);
event Withdrawn(address indexed user, uint256 amount);
event RewardPaid(address indexed user, uint256 reward);
modifier updateReward(address account) {
rewardPerTokenStored = rewardPerToken();
lastUpdateTime = lastTimeRewardApplicable();
if (account != address(0)) {
rewards[account] = earned(account);
userRewardPerTokenPaid[account] = rewardPerTokenStored;
}
_;
}
function lastTimeRewardApplicable() public view returns (uint256) {
return Math.min(block.timestamp, periodFinish);
}
function rewardPerToken() public view returns (uint256) {
if (totalSupply() == 0) {
return rewardPerTokenStored;
}
return rewardPerTokenStored.add(
lastTimeRewardApplicable()
.sub(lastUpdateTime)
.mul(rewardRate)
.mul(1e18)
.div(totalSupply())
);
}
function earned(address account) public view returns (uint256) {
return balanceOf(account)
.mul(rewardPerToken().sub(userRewardPerTokenPaid[account]))
.div(1E18)
.add(rewards[account]);
}
function stake(uint256 amount) public updateReward(msg.sender) {
require(amount > 0, 'Cannot stake 0');
_stake(amount);
emit Staked(msg.sender, amount);
}
function withdraw(uint256 amount) public updateReward(msg.sender) {
require(amount > 0, 'Cannot withdraw 0');
_withdraw(amount);
emit Withdrawn(msg.sender, amount);
}
function exit() external {
withdraw(balanceOf(msg.sender));
getReward();
}
function getReward() public updateReward(msg.sender) returns (uint256 reward) {
reward = earned(msg.sender);
if (reward > 0) {
rewards[msg.sender] = 0;
bcug.safeTransfer(msg.sender, reward);
emit RewardPaid(msg.sender, reward);
}
}
function notifyRewardAmount(uint256 reward) external onlyOwner updateReward(address(0x0)) {
if (block.timestamp >= periodFinish) {
rewardRate = reward.div(DURATION);
} else {
uint256 remaining = periodFinish.sub(block.timestamp);
uint256 leftover = remaining.mul(rewardRate);
rewardRate = reward.add(leftover).div(DURATION);
}
lastUpdateTime = block.timestamp;
periodFinish = block.timestamp.add(DURATION);
emit RewardAdded(reward);
}
}