// File: contracts/interfaces/IVeERC20.sol
pragma solidity ^0.6.12;
/// @title Vote Escrow ERC20 Token Interface
/// @notice Interface of a ERC20 token used for vote escrow and boosted farm. Notice that transfers and
/// allowances are disabled
interface IVeERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
}
// File: @openzeppelin/contracts/utils/Context.sol
pragma solidity >=0.6.0 <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 GSN 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 payable) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
// File: contracts/VeERC20.sol
pragma solidity ^0.6.12;
/// @title VeERC20
/// @notice Modified version of ERC20 where transfers and allowances are disabled.
/// @dev Only minting and burning are allowed. The hook `_beforeTokenOperation` and
/// `_afterTokenOperation` methods are called before and after minting/burning respectively.
contract VeERC20 is Context, IVeERC20 {
mapping(address => uint256) private _balances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/// @dev Emitted when `value` tokens are burned and minted
event Burn(address indexed account, uint256 value);
event Mint(address indexed beneficiary, uint256 value);
/**
* @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_) public {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual 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 pure virtual 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 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");
_beforeTokenOperation(address(0), account, amount);
_totalSupply += amount;
_balances[account] += amount;
emit Mint(account, amount);
_afterTokenOperation(account, _balances[account]);
}
/**
* @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");
_beforeTokenOperation(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
_balances[account] = accountBalance - amount;
_totalSupply -= amount;
emit Burn(account, amount);
_afterTokenOperation(account, _balances[account]);
}
/**
* @dev Hook that is called before any minting and burning.
* @param from the account transferring tokens
* @param to the account receiving tokens
* @param amount the amount being minted or burned
*/
function _beforeTokenOperation(
address from,
address to,
uint256 amount
) internal virtual {}
/**
* @dev Hook that is called after any minting and burning.
* @param account the account being affected
* @param newBalance the new balance of `account` after minting/burning
*/
function _afterTokenOperation(address account, uint256 newBalance) internal virtual {}
}
// File: @openzeppelin/contracts/access/Ownable.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @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 () internal {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), 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 {
emit OwnershipTransferred(_owner, address(0));
_owner = 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");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
// File: contracts/VeNETT.sol
pragma solidity ^0.6.12;
interface IBoostedNETTFarm {
function updateFactor(address, uint256) external;
}
/// @title Vote Escrow NETT - veNETT
/// @notice Infinite supply, used to receive extra farming yields and voting power
contract VeNETT is VeERC20("VeNETT", "veNETT"), Ownable {
/// @notice the BoostedNETTFarm contract
IBoostedNETTFarm public boostedNETTFarm;
event UpdateBoostedNETTFarm(address indexed user, address boostedNETTFarm);
/// @dev Creates `_amount` token to `_to`. Must only be called by the owner (VeNETTStaking)
/// @param _to The address that will receive the mint
/// @param _amount The amount to be minted
function mint(address _to, uint256 _amount) external onlyOwner {
_mint(_to, _amount);
}
/// @dev Destroys `_amount` tokens from `_from`. Callable only by the owner (VeNETTStaking)
/// @param _from The address that will burn tokens
/// @param _amount The amount to be burned
function burnFrom(address _from, uint256 _amount) external onlyOwner {
_burn(_from, _amount);
}
/// @dev Sets the address of the BoostedNETTFarm contract this updates
/// @param _boostedNETTFarm the address of BoostedFarm
function setBoostedNETTFarm(address _boostedNETTFarm) external onlyOwner {
// We allow 0 address here if we want to disable the callback operations
boostedNETTFarm = IBoostedNETTFarm(_boostedNETTFarm);
emit UpdateBoostedNETTFarm(_msgSender(), _boostedNETTFarm);
}
function _afterTokenOperation(address _account, uint256 _newBalance) internal override {
if (address(boostedNETTFarm) != address(0)) {
boostedNETTFarm.updateFactor(_account, _newBalance);
}
}
function renounceOwnership() public override onlyOwner {
revert("VeNETT: Cannot renounce, can only transfer ownership");
}
}
// File: @openzeppelin/contracts/utils/Address.sol
pragma solidity >=0.6.2 <0.8.0;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(bool success, ) = recipient.call{ value: amount }("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain`call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{ value: value }(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.delegatecall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// File: @openzeppelin/contracts/math/SafeMath.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
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) {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
/**
* @dev Returns the substraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
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) {
// 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) {
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) {
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) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @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) {
require(b <= a, "SafeMath: subtraction overflow");
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) {
if (a == 0) return 0;
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @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. 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) internal pure returns (uint256) {
require(b > 0, "SafeMath: division by zero");
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) {
require(b > 0, "SafeMath: modulo by zero");
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) {
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.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryDiv}.
*
* 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) {
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) {
require(b > 0, errorMessage);
return a % b;
}
}
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @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 `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);
/**
* @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);
}
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
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));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
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, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// File: @openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol
pragma solidity >=0.6.2 <0.8.0;
/**
* @dev Collection of functions related to the address type
*/
library AddressUpgradeable {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(bool success, ) = recipient.call{ value: amount }("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain`call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{ value: value }(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// File: @openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20Upgradeable {
/**
* @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 `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);
/**
* @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);
}
// File: @openzeppelin/contracts-upgradeable/math/SafeMathUpgradeable.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMathUpgradeable {
/**
* @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) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @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 sub(a, b, "SafeMath: subtraction overflow");
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
/**
* @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) {
// 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 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts 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) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts 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) {
require(b > 0, errorMessage);
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts 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 mod(a, b, "SafeMath: modulo by zero");
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}
// File: @openzeppelin/contracts-upgradeable/token/ERC20/SafeERC20Upgradeable.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20Upgradeable {
using SafeMathUpgradeable for uint256;
using AddressUpgradeable for address;
function safeTransfer(IERC20Upgradeable token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20Upgradeable token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20Upgradeable token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
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(IERC20Upgradeable 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(IERC20Upgradeable token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20Upgradeable token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// File: @openzeppelin/contracts-upgradeable/proxy/Initializable.sol
// solhint-disable-next-line compiler-version
pragma solidity >=0.4.24 <0.8.0;
/**
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
* behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
*
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
* possible by providing the encoded function call as the `_data` argument to {UpgradeableProxy-constructor}.
*
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
*/
abstract contract Initializable {
/**
* @dev Indicates that the contract has been initialized.
*/
bool private _initialized;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool private _initializing;
/**
* @dev Modifier to protect an initializer function from being invoked twice.
*/
modifier initializer() {
require(_initializing || _isConstructor() || !_initialized, "Initializable: contract is already initialized");
bool isTopLevelCall = !_initializing;
if (isTopLevelCall) {
_initializing = true;
_initialized = true;
}
_;
if (isTopLevelCall) {
_initializing = false;
}
}
/// @dev Returns true if and only if the function is running in the constructor
function _isConstructor() private view returns (bool) {
// extcodesize checks the size of the code stored in an address, and
// address returns the current address. Since the code is still not
// deployed when running a constructor, any checks on its code size will
// yield zero, making it an effective way to detect if a contract is
// under construction or not.
address self = address(this);
uint256 cs;
// solhint-disable-next-line no-inline-assembly
assembly { cs := extcodesize(self) }
return cs == 0;
}
}
// File: @openzeppelin/contracts-upgradeable/GSN/ContextUpgradeable.sol
pragma solidity >=0.6.0 <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 GSN 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 ContextUpgradeable is Initializable {
function __Context_init() internal initializer {
__Context_init_unchained();
}
function __Context_init_unchained() internal initializer {
}
function _msgSender() internal view virtual returns (address payable) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
uint256[50] private __gap;
}
// File: @openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol
pragma solidity >=0.6.0 <0.8.0;
/**
* @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 OwnableUpgradeable is Initializable, ContextUpgradeable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
function __Ownable_init() internal initializer {
__Context_init_unchained();
__Ownable_init_unchained();
}
function __Ownable_init_unchained() internal initializer {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view 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 {
emit OwnershipTransferred(_owner, address(0));
_owner = 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");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
uint256[49] private __gap;
}
// File: contracts/VeNETTStaking.sol
pragma solidity ^0.6.12;
pragma experimental ABIEncoderV2;
/// @title Vote Escrow NETT Staking
/// @notice Stake NETT to earn veNETT, which you can use to earn higher farm yields and gain
/// voting power. Note that unstaking any amount of NETT will burn all of your existing veNETT.
contract VeNETTStaking is Initializable, OwnableUpgradeable {
using SafeMathUpgradeable for uint256;
using SafeERC20Upgradeable for IERC20Upgradeable;
/// @notice Info for each user
/// `balance`: Amount of NETT currently staked by user
/// `rewardDebt`: The reward debt of the user
/// `lastClaimTimestamp`: The timestamp of user's last claim or withdraw
/// `speedUpEndTimestamp`: The timestamp when user stops receiving speed up benefits, or
/// zero if user is not currently receiving speed up benefits
struct UserInfo {
uint256 balance;
uint256 rewardDebt;
uint256 lastClaimTimestamp;
uint256 speedUpEndTimestamp;
/**
* @notice We do some fancy math here. Basically, any point in time, the amount of veNETT
* entitled to a user but is pending to be distributed is:
*
* pendingReward = pendingBaseReward + pendingSpeedUpReward
*
* pendingBaseReward = (user.balance * accVeNETTPerShare) - user.rewardDebt
*
* if user.speedUpEndTimestamp != 0:
* speedUpCeilingTimestamp = min(block.timestamp, user.speedUpEndTimestamp)
* speedUpSecondsElapsed = speedUpCeilingTimestamp - user.lastClaimTimestamp
* pendingSpeedUpReward = speedUpSecondsElapsed * user.balance * speedUpVeNETTPerSharePerSec
* else:
* pendingSpeedUpReward = 0
*/
}
IERC20Upgradeable public nett;
VeNETT public veNETT;
// @notice The maximum limit of veNETT user can have as percentage points of staked NETT
/// For example, if user has `n` NETT staked, they can own a maximum of `n * maxCapPct / 100` veNETT.
uint256 public maxCapPct;
/// @notice The upper limit of `maxCapPct`
uint256 public upperLimitMaxCapPct;
/// @notice The accrued veNETT per share, scaled to `ACC_VENETT_PER_SHARE_PRECISION`
uint256 public accVeNETTPerShare;
/// @notice Precision of `accVeNETTPerShare`
uint256 public ACC_VENETT_PER_SHARE_PRECISION;
/// @notice The last time that the reward variables were updated
uint256 public lastRewardTimestamp;
/// @notice veNETT per sec per NETT staked, scaled to `VENETT_PER_SHARE_PER_SEC_PRECISION`
uint256 public veNETTPerSharePerSec;
/// @notice Speed up veNETT per sec per NETT staked, scaled to `VENETT_PER_SHARE_PER_SEC_PRECISION`
uint256 public speedUpVeNETTPerSharePerSec;
/// @notice The upper limit of `veNETTPerSharePerSec` and `speedUpVeNETTPerSharePerSec`
uint256 public upperLimitVeNETTPerSharePerSec;
/// @notice Precision of `veNETTPerSharePerSec`
uint256 public VENETT_PER_SHARE_PER_SEC_PRECISION;
/// @notice Percentage of user's current staked NETT user has to deposit in order to start
/// receiving speed up benefits, in parts per 100.
/// @dev Specifically, user has to deposit at least `speedUpThreshold/100 * userStakedNETT` NETT.
/// The only exception is the user will also receive speed up benefits if they are depositing
/// with zero balance
uint256 public speedUpThreshold;
/// @notice The length of time a user receives speed up benefits
uint256 public speedUpDuration;
mapping(address => UserInfo) public userInfos;
event Claim(address indexed user, uint256 amount);
event Deposit(address indexed user, uint256 amount);
event UpdateMaxCapPct(address indexed user, uint256 maxCapPct);
event UpdateRewardVars(uint256 lastRewardTimestamp, uint256 accVeNETTPerShare);
event UpdateSpeedUpThreshold(address indexed user, uint256 speedUpThreshold);
event UpdateVeNETTPerSharePerSec(address indexed user, uint256 veNETTPerSharePerSec);
event Withdraw(address indexed user, uint256 withdrawAmount, uint256 burnAmount);
/// @notice Initialize with needed parameters
/// @param _nett Address of the NETT token contract
/// @param _veNETT Address of the veNETT token contract
/// @param _veNETTPerSharePerSec veNETT per sec per NETT staked, scaled to `VENETT_PER_SHARE_PER_SEC_PRECISION`
/// @param _speedUpVeNETTPerSharePerSec Similar to `_veNETTPerSharePerSec` but for speed up
/// @param _speedUpThreshold Percentage of total staked NETT user has to deposit receive speed up
/// @param _speedUpDuration Length of time a user receives speed up benefits
/// @param _maxCapPct Maximum limit of veNETT user can have as percentage points of staked NETT
function initialize(
IERC20Upgradeable _nett,
VeNETT _veNETT,
uint256 _veNETTPerSharePerSec,
uint256 _speedUpVeNETTPerSharePerSec,
uint256 _speedUpThreshold,
uint256 _speedUpDuration,
uint256 _maxCapPct
) public initializer {
__Ownable_init();
require(address(_nett) != address(0), "VeNETTStaking: unexpected zero address for _nett");
require(address(_veNETT) != address(0), "VeNETTStaking: unexpected zero address for _veNETT");
upperLimitVeNETTPerSharePerSec = 1e36;
require(
_veNETTPerSharePerSec <= upperLimitVeNETTPerSharePerSec,
"VeNETTStaking: expected _veNETTPerSharePerSec to be <= 1e36"
);
require(
_speedUpVeNETTPerSharePerSec <= upperLimitVeNETTPerSharePerSec,
"VeNETTStaking: expected _speedUpVeNETTPerSharePerSec to be <= 1e36"
);
require(
_speedUpThreshold != 0 && _speedUpThreshold <= 100,
"VeNETTStaking: expected _speedUpThreshold to be > 0 and <= 100"
);
require(_speedUpDuration <= 365 days, "VeNETTStaking: expected _speedUpDuration to be <= 365 days");
upperLimitMaxCapPct = 10000000;
require(
_maxCapPct != 0 && _maxCapPct <= upperLimitMaxCapPct,
"VeNETTStaking: expected _maxCapPct to be non-zero and <= 10000000"
);
maxCapPct = _maxCapPct;
speedUpThreshold = _speedUpThreshold;
speedUpDuration = _speedUpDuration;
nett = _nett;
veNETT = _veNETT;
veNETTPerSharePerSec = _veNETTPerSharePerSec;
speedUpVeNETTPerSharePerSec = _speedUpVeNETTPerSharePerSec;
lastRewardTimestamp = block.timestamp;
ACC_VENETT_PER_SHARE_PRECISION = 1e18;
VENETT_PER_SHARE_PER_SEC_PRECISION = 1e18;
}
/// @notice Set maxCapPct
/// @param _maxCapPct The new maxCapPct
function setMaxCapPct(uint256 _maxCapPct) external onlyOwner {
require(_maxCapPct > maxCapPct, "VeNETTStaking: expected new _maxCapPct to be greater than existing maxCapPct");
require(
_maxCapPct != 0 && _maxCapPct <= upperLimitMaxCapPct,
"VeNETTStaking: expected new _maxCapPct to be non-zero and <= 10000000"
);
maxCapPct = _maxCapPct;
emit UpdateMaxCapPct(_msgSender(), _maxCapPct);
}
/// @notice Set veNETTPerSharePerSec
/// @param _veNETTPerSharePerSec The new veNETTPerSharePerSec
function setVeNETTPerSharePerSec(uint256 _veNETTPerSharePerSec) external onlyOwner {
require(
_veNETTPerSharePerSec <= upperLimitVeNETTPerSharePerSec,
"VeNETTStaking: expected _veNETTPerSharePerSec to be <= 1e36"
);
updateRewardVars();
veNETTPerSharePerSec = _veNETTPerSharePerSec;
emit UpdateVeNETTPerSharePerSec(_msgSender(), _veNETTPerSharePerSec);
}
/// @notice Set speedUpThreshold
/// @param _speedUpThreshold The new speedUpThreshold
function setSpeedUpThreshold(uint256 _speedUpThreshold) external onlyOwner {
require(
_speedUpThreshold != 0 && _speedUpThreshold <= 100,
"VeNETTStaking: expected _speedUpThreshold to be > 0 and <= 100"
);
speedUpThreshold = _speedUpThreshold;
emit UpdateSpeedUpThreshold(_msgSender(), _speedUpThreshold);
}
/// @notice Deposits NETT to start staking for veNETT. Note that any pending veNETT
/// will also be claimed in the process.
/// @param _amount The amount of NETT to deposit
function deposit(uint256 _amount) external {
require(_amount > 0, "VeNETTStaking: expected deposit amount to be greater than zero");
updateRewardVars();
UserInfo storage userInfo = userInfos[_msgSender()];
if (_getUserHasNonZeroBalance(_msgSender())) {
// Transfer to the user their pending veNETT before updating their UserInfo
_claim();
// We need to update user's `lastClaimTimestamp` to now to prevent
// passive veNETT accrual if user hit their max cap.
userInfo.lastClaimTimestamp = block.timestamp;
uint256 userStakedNETT = userInfo.balance;
// User is eligible for speed up benefits if `_amount` is at least
// `speedUpThreshold / 100 * userStakedNETT`
if (_amount.mul(100) >= speedUpThreshold.mul(userStakedNETT)) {
userInfo.speedUpEndTimestamp = block.timestamp.add(speedUpDuration);
}
} else {
// If user is depositing with zero balance, they will automatically
// receive speed up benefits
userInfo.speedUpEndTimestamp = block.timestamp.add(speedUpDuration);
userInfo.lastClaimTimestamp = block.timestamp;
}
userInfo.balance = userInfo.balance.add(_amount);
userInfo.rewardDebt = accVeNETTPerShare.mul(userInfo.balance).div(ACC_VENETT_PER_SHARE_PRECISION);
nett.safeTransferFrom(_msgSender(), address(this), _amount);
emit Deposit(_msgSender(), _amount);
}
/// @notice Withdraw staked NETT. Note that unstaking any amount of NETT means you will
/// lose all of your current veNETT.
/// @param _amount The amount of NETT to unstake
function withdraw(uint256 _amount) external {
require(_amount > 0, "VeNETTStaking: expected withdraw amount to be greater than zero");
UserInfo storage userInfo = userInfos[_msgSender()];
require(
userInfo.balance >= _amount,
"VeNETTStaking: cannot withdraw greater amount of NETT than currently staked"
);
updateRewardVars();
// Note that we don't need to claim as the user's veNETT balance will be reset to 0
userInfo.balance = userInfo.balance.sub(_amount);
userInfo.rewardDebt = accVeNETTPerShare.mul(userInfo.balance).div(ACC_VENETT_PER_SHARE_PRECISION);
userInfo.lastClaimTimestamp = block.timestamp;
userInfo.speedUpEndTimestamp = 0;
// Burn the user's current veNETT balance
uint256 userVeNETTBalance = veNETT.balanceOf(_msgSender());
veNETT.burnFrom(_msgSender(), userVeNETTBalance);
// Send user their requested amount of staked NETT
nett.safeTransfer(_msgSender(), _amount);
emit Withdraw(_msgSender(), _amount, userVeNETTBalance);
}
/// @notice Claim any pending veNETT
function claim() external {
require(_getUserHasNonZeroBalance(_msgSender()), "VeNETTStaking: cannot claim veNETT when no NETT is staked");
updateRewardVars();
_claim();
}
/// @notice Get the pending amount of veNETT for a given user
/// @param _user The user to lookup
/// @return The number of pending veNETT tokens for `_user`
function getPendingVeNETT(address _user) public view returns (uint256) {
if (!_getUserHasNonZeroBalance(_user)) {
return 0;
}
UserInfo memory user = userInfos[_user];
// Calculate amount of pending base veNETT
uint256 _accVeNETTPerShare = accVeNETTPerShare;
uint256 secondsElapsed = block.timestamp.sub(lastRewardTimestamp);
if (secondsElapsed > 0) {
_accVeNETTPerShare = _accVeNETTPerShare.add(
secondsElapsed.mul(veNETTPerSharePerSec).mul(ACC_VENETT_PER_SHARE_PRECISION).div(
VENETT_PER_SHARE_PER_SEC_PRECISION
)
);
}
uint256 pendingBaseVeNETT = _accVeNETTPerShare.mul(user.balance).div(ACC_VENETT_PER_SHARE_PRECISION).sub(
user.rewardDebt
);
// Calculate amount of pending speed up veNETT
uint256 pendingSpeedUpVeNETT;
if (user.speedUpEndTimestamp != 0) {
uint256 speedUpCeilingTimestamp = block.timestamp > user.speedUpEndTimestamp
? user.speedUpEndTimestamp
: block.timestamp;
uint256 speedUpSecondsElapsed = speedUpCeilingTimestamp.sub(user.lastClaimTimestamp);
uint256 speedUpAccVeNETTPerShare = speedUpSecondsElapsed.mul(speedUpVeNETTPerSharePerSec);
pendingSpeedUpVeNETT = speedUpAccVeNETTPerShare.mul(user.balance).div(VENETT_PER_SHARE_PER_SEC_PRECISION);
}
uint256 pendingVeNETT = pendingBaseVeNETT.add(pendingSpeedUpVeNETT);
// Get the user's current veNETT balance
uint256 userVeNETTBalance = veNETT.balanceOf(_user);
// This is the user's max veNETT cap multiplied by 100
uint256 scaledUserMaxVeNETTCap = user.balance.mul(maxCapPct);
if (userVeNETTBalance.mul(100) >= scaledUserMaxVeNETTCap) {
// User already holds maximum amount of veNETT so there is no pending veNETT
return 0;
} else if (userVeNETTBalance.add(pendingVeNETT).mul(100) > scaledUserMaxVeNETTCap) {
return scaledUserMaxVeNETTCap.sub(userVeNETTBalance.mul(100)).div(100);
} else {
return pendingVeNETT;
}
}
/// @notice Update reward variables
function updateRewardVars() public {
if (block.timestamp <= lastRewardTimestamp) {
return;
}
if (nett.balanceOf(address(this)) == 0) {
lastRewardTimestamp = block.timestamp;
return;
}
uint256 secondsElapsed = block.timestamp.sub(lastRewardTimestamp);
accVeNETTPerShare = accVeNETTPerShare.add(
secondsElapsed.mul(veNETTPerSharePerSec).mul(ACC_VENETT_PER_SHARE_PRECISION).div(
VENETT_PER_SHARE_PER_SEC_PRECISION
)
);
lastRewardTimestamp = block.timestamp;
emit UpdateRewardVars(lastRewardTimestamp, accVeNETTPerShare);
}
/// @notice Checks to see if a given user currently has staked NETT
/// @param _user The user address to check
/// @return Whether `_user` currently has staked NETT
function _getUserHasNonZeroBalance(address _user) private view returns (bool) {
return userInfos[_user].balance > 0;
}
/// @dev Helper to claim any pending veNETT
function _claim() private {
uint256 veNETTToClaim = getPendingVeNETT(_msgSender());
UserInfo storage userInfo = userInfos[_msgSender()];
userInfo.rewardDebt = accVeNETTPerShare.mul(userInfo.balance).div(ACC_VENETT_PER_SHARE_PRECISION);
// If user's speed up period has ended, reset `speedUpEndTimestamp` to 0
if (userInfo.speedUpEndTimestamp != 0 && block.timestamp >= userInfo.speedUpEndTimestamp) {
userInfo.speedUpEndTimestamp = 0;
}
if (veNETTToClaim > 0) {
userInfo.lastClaimTimestamp = block.timestamp;
veNETT.mint(_msgSender(), veNETTToClaim);
emit Claim(_msgSender(), veNETTToClaim);
}
}
}