//SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;

/**
 * @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;
		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");

		(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");

		(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");

		(bool success, bytes memory returndata) = target.staticcall(data);
		return verifyCallResult(success, returndata, errorMessage);
	}

	/**
	 * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
	 * revert reason using the provided one.
	 *
	 * _Available since v4.3._
	 */
	function verifyCallResult(
		bool success,
		bytes memory returndata,
		string memory errorMessage
	) internal 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

				assembly {
					let returndata_size := mload(returndata)
					revert(add(32, returndata), returndata_size)
				}
			} else {
				revert(errorMessage);
			}
		}
	}
}

/**
 * @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);
}

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20MetadataUpgradeable is IERC20Upgradeable {
	/**
	 * @dev Returns the name of the token.
	 */
	function name() external view returns (string memory);

	/**
	 * @dev Returns the symbol of the token.
	 */
	function symbol() external view returns (string memory);

	/**
	 * @dev Returns the decimals places of the token.
	 */
	function decimals() external view returns (uint8);
}

/**
 * @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 {ERC1967Proxy-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.
 *
 * [CAUTION]
 * ====
 * Avoid leaving a contract uninitialized.
 *
 * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
 * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
 * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() initializer {}
 * ```
 * ====
 */
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() {
		// If the contract is initializing we ignore whether _initialized is set in order to support multiple
		// inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
		// contract may have been reentered.
		require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");

		bool isTopLevelCall = !_initializing;
		if (isTopLevelCall) {
			_initializing = true;
			_initialized = true;
		}

		_;

		if (isTopLevelCall) {
			_initializing = false;
		}
	}

	/**
	 * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
	 * {initializer} modifier, directly or indirectly.
	 */
	modifier onlyInitializing() {
		require(_initializing, "Initializable: contract is not initializing");
		_;
	}

	function _isConstructor() private view returns (bool) {
		return !AddressUpgradeable.isContract(address(this));
	}
}

/**
 * @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 ContextUpgradeable is Initializable {
	function __Context_init() internal onlyInitializing {
		__Context_init_unchained();
	}

	function __Context_init_unchained() internal onlyInitializing {}

	function _msgSender() internal view virtual returns (address) {
		return msg.sender;
	}

	function _msgData() internal view virtual returns (bytes calldata) {
		return msg.data;
	}

	uint256[50] private __gap;
}

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20Upgradeable is Initializable, ContextUpgradeable, IERC20Upgradeable, IERC20MetadataUpgradeable {
	mapping(address => uint256) private _balances;

	mapping(address => mapping(address => uint256)) private _allowances;

	uint256 private _totalSupply;

	string private _name;
	string private _symbol;

	/**
	 * @dev Sets the values for {name} and {symbol}.
	 *
	 * The default value of {decimals} is 18. To select a different value for
	 * {decimals} you should overload it.
	 *
	 * All two of these values are immutable: they can only be set once during
	 * construction.
	 */
	function __ERC20_init(string memory name_, string memory symbol_) internal onlyInitializing {
		__Context_init_unchained();
		__ERC20_init_unchained(name_, symbol_);
	}

	function __ERC20_init_unchained(string memory name_, string memory symbol_) internal onlyInitializing {
		_name = name_;
		_symbol = symbol_;
	}

	/**
	 * @dev Returns the name of the token.
	 */
	function name() public view virtual override returns (string memory) {
		return _name;
	}

	/**
	 * @dev Returns the symbol of the token, usually a shorter version of the
	 * name.
	 */
	function symbol() public view virtual override returns (string memory) {
		return _symbol;
	}

	/**
	 * @dev Returns the number of decimals used to get its user representation.
	 * For example, if `decimals` equals `2`, a balance of `505` tokens should
	 * be displayed to a user as `5.05` (`505 / 10 ** 2`).
	 *
	 * Tokens usually opt for a value of 18, imitating the relationship between
	 * Ether and Wei. This is the value {ERC20} uses, unless this function is
	 * overridden;
	 *
	 * NOTE: This information is only used for _display_ purposes: it in
	 * no way affects any of the arithmetic of the contract, including
	 * {IERC20-balanceOf} and {IERC20-transfer}.
	 */
	function decimals() public view virtual override returns (uint8) {
		return 18;
	}

	/**
	 * @dev See {IERC20-totalSupply}.
	 */
	function totalSupply() public view virtual override returns (uint256) {
		return _totalSupply;
	}

	/**
	 * @dev See {IERC20-balanceOf}.
	 */
	function balanceOf(address account) public view virtual override returns (uint256) {
		return _balances[account];
	}

	/**
	 * @dev See {IERC20-transfer}.
	 *
	 * Requirements:
	 *
	 * - `recipient` cannot be the zero address.
	 * - the caller must have a balance of at least `amount`.
	 */
	function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
		_transfer(_msgSender(), recipient, amount);
		return true;
	}

	/**
	 * @dev See {IERC20-allowance}.
	 */
	function allowance(address owner, address spender) public view virtual override returns (uint256) {
		return _allowances[owner][spender];
	}

	/**
	 * @dev See {IERC20-approve}.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 */
	function approve(address spender, uint256 amount) public virtual override returns (bool) {
		_approve(_msgSender(), spender, amount);
		return true;
	}

	/**
	 * @dev See {IERC20-transferFrom}.
	 *
	 * Emits an {Approval} event indicating the updated allowance. This is not
	 * required by the EIP. See the note at the beginning of {ERC20}.
	 *
	 * Requirements:
	 *
	 * - `sender` and `recipient` cannot be the zero address.
	 * - `sender` must have a balance of at least `amount`.
	 * - the caller must have allowance for ``sender``'s tokens of at least
	 * `amount`.
	 */
	function transferFrom(
		address sender,
		address recipient,
		uint256 amount
	) public virtual override returns (bool) {
		_transfer(sender, recipient, amount);

		uint256 currentAllowance = _allowances[sender][_msgSender()];
		require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
		unchecked {
			_approve(sender, _msgSender(), currentAllowance - amount);
		}

		return true;
	}

	/**
	 * @dev Atomically increases the allowance granted to `spender` by the caller.
	 *
	 * This is an alternative to {approve} that can be used as a mitigation for
	 * problems described in {IERC20-approve}.
	 *
	 * Emits an {Approval} event indicating the updated allowance.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 */
	function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
		_approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
		return true;
	}

	/**
	 * @dev Atomically decreases the allowance granted to `spender` by the caller.
	 *
	 * This is an alternative to {approve} that can be used as a mitigation for
	 * problems described in {IERC20-approve}.
	 *
	 * Emits an {Approval} event indicating the updated allowance.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 * - `spender` must have allowance for the caller of at least
	 * `subtractedValue`.
	 */
	function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
		uint256 currentAllowance = _allowances[_msgSender()][spender];
		require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
		unchecked {
			_approve(_msgSender(), spender, currentAllowance - subtractedValue);
		}

		return true;
	}

	/**
	 * @dev Moves `amount` of tokens from `sender` to `recipient`.
	 *
	 * This internal function is equivalent to {transfer}, and can be used to
	 * e.g. implement automatic token fees, slashing mechanisms, etc.
	 *
	 * Emits a {Transfer} event.
	 *
	 * Requirements:
	 *
	 * - `sender` cannot be the zero address.
	 * - `recipient` cannot be the zero address.
	 * - `sender` must have a balance of at least `amount`.
	 */
	function _transfer(
		address sender,
		address recipient,
		uint256 amount
	) internal virtual {
		require(sender != address(0), "ERC20: transfer from the zero address");
		require(recipient != address(0), "ERC20: transfer to the zero address");

		_beforeTokenTransfer(sender, recipient, amount);

		uint256 senderBalance = _balances[sender];
		require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
		unchecked {
			_balances[sender] = senderBalance - amount;
		}
		_balances[recipient] += amount;

		emit Transfer(sender, recipient, amount);

		_afterTokenTransfer(sender, recipient, amount);
	}

	/** @dev Creates `amount` tokens and assigns them to `account`, increasing
	 * the total supply.
	 *
	 * Emits a {Transfer} event with `from` set to the zero address.
	 *
	 * Requirements:
	 *
	 * - `account` cannot be the zero address.
	 */
	function _mint(address account, uint256 amount) internal virtual {
		require(account != address(0), "ERC20: mint to the zero address");

		_beforeTokenTransfer(address(0), account, amount);

		_totalSupply += amount;
		_balances[account] += amount;
		emit Transfer(address(0), account, amount);

		_afterTokenTransfer(address(0), account, amount);
	}

	/**
	 * @dev Destroys `amount` tokens from `account`, reducing the
	 * total supply.
	 *
	 * Emits a {Transfer} event with `to` set to the zero address.
	 *
	 * Requirements:
	 *
	 * - `account` cannot be the zero address.
	 * - `account` must have at least `amount` tokens.
	 */
	function _burn(address account, uint256 amount) internal virtual {
		require(account != address(0), "ERC20: burn from the zero address");

		_beforeTokenTransfer(account, address(0), amount);

		uint256 accountBalance = _balances[account];
		require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
		unchecked {
			_balances[account] = accountBalance - amount;
		}
		_totalSupply -= amount;

		emit Transfer(account, address(0), amount);

		_afterTokenTransfer(account, address(0), amount);
	}

	/**
	 * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
	 *
	 * This internal function is equivalent to `approve`, and can be used to
	 * e.g. set automatic allowances for certain subsystems, etc.
	 *
	 * Emits an {Approval} event.
	 *
	 * Requirements:
	 *
	 * - `owner` cannot be the zero address.
	 * - `spender` cannot be the zero address.
	 */
	function _approve(
		address owner,
		address spender,
		uint256 amount
	) internal virtual {
		require(owner != address(0), "ERC20: approve from the zero address");
		require(spender != address(0), "ERC20: approve to the zero address");

		_allowances[owner][spender] = amount;
		emit Approval(owner, spender, amount);
	}

	/**
	 * @dev Hook that is called before any transfer of tokens. This includes
	 * minting and burning.
	 *
	 * Calling conditions:
	 *
	 * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
	 * will be transferred to `to`.
	 * - when `from` is zero, `amount` tokens will be minted for `to`.
	 * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
	 * - `from` and `to` are never both zero.
	 *
	 * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
	 */
	function _beforeTokenTransfer(
		address from,
		address to,
		uint256 amount
	) internal virtual {}

	/**
	 * @dev Hook that is called after any transfer of tokens. This includes
	 * minting and burning.
	 *
	 * Calling conditions:
	 *
	 * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
	 * has been transferred to `to`.
	 * - when `from` is zero, `amount` tokens have been minted for `to`.
	 * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
	 * - `from` and `to` are never both zero.
	 *
	 * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
	 */
	function _afterTokenTransfer(
		address from,
		address to,
		uint256 amount
	) internal virtual {}

	uint256[45] private __gap;
}

/**
 * @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 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'
		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) + value;
		_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
	}

	function safeDecreaseAllowance(
		IERC20Upgradeable token,
		address spender,
		uint256 value
	) internal {
		unchecked {
			uint256 oldAllowance = token.allowance(address(this), spender);
			require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
			uint256 newAllowance = oldAllowance - value;
			_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
			require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
		}
	}
}

/**
 * @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);
}

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
	/**
	 * @dev Returns the name of the token.
	 */
	function name() external view returns (string memory);

	/**
	 * @dev Returns the symbol of the token.
	 */
	function symbol() external view returns (string memory);

	/**
	 * @dev Returns the decimals places of the token.
	 */
	function decimals() external view returns (uint8);
}

/**
 * @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;
	}
}

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
	mapping(address => uint256) private _balances;

	mapping(address => mapping(address => uint256)) private _allowances;

	uint256 private _totalSupply;

	string private _name;
	string private _symbol;

	/**
	 * @dev Sets the values for {name} and {symbol}.
	 *
	 * The default value of {decimals} is 18. To select a different value for
	 * {decimals} you should overload it.
	 *
	 * All two of these values are immutable: they can only be set once during
	 * construction.
	 */
	constructor(string memory name_, string memory symbol_) {
		_name = name_;
		_symbol = symbol_;
	}

	/**
	 * @dev Returns the name of the token.
	 */
	function name() public view virtual override returns (string memory) {
		return _name;
	}

	/**
	 * @dev Returns the symbol of the token, usually a shorter version of the
	 * name.
	 */
	function symbol() public view virtual override returns (string memory) {
		return _symbol;
	}

	/**
	 * @dev Returns the number of decimals used to get its user representation.
	 * For example, if `decimals` equals `2`, a balance of `505` tokens should
	 * be displayed to a user as `5.05` (`505 / 10 ** 2`).
	 *
	 * Tokens usually opt for a value of 18, imitating the relationship between
	 * Ether and Wei. This is the value {ERC20} uses, unless this function is
	 * overridden;
	 *
	 * NOTE: This information is only used for _display_ purposes: it in
	 * no way affects any of the arithmetic of the contract, including
	 * {IERC20-balanceOf} and {IERC20-transfer}.
	 */
	function decimals() public view virtual override returns (uint8) {
		return 18;
	}

	/**
	 * @dev See {IERC20-totalSupply}.
	 */
	function totalSupply() public view virtual override returns (uint256) {
		return _totalSupply;
	}

	/**
	 * @dev See {IERC20-balanceOf}.
	 */
	function balanceOf(address account) public view virtual override returns (uint256) {
		return _balances[account];
	}

	/**
	 * @dev See {IERC20-transfer}.
	 *
	 * Requirements:
	 *
	 * - `recipient` cannot be the zero address.
	 * - the caller must have a balance of at least `amount`.
	 */
	function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
		_transfer(_msgSender(), recipient, amount);
		return true;
	}

	/**
	 * @dev See {IERC20-allowance}.
	 */
	function allowance(address owner, address spender) public view virtual override returns (uint256) {
		return _allowances[owner][spender];
	}

	/**
	 * @dev See {IERC20-approve}.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 */
	function approve(address spender, uint256 amount) public virtual override returns (bool) {
		_approve(_msgSender(), spender, amount);
		return true;
	}

	/**
	 * @dev See {IERC20-transferFrom}.
	 *
	 * Emits an {Approval} event indicating the updated allowance. This is not
	 * required by the EIP. See the note at the beginning of {ERC20}.
	 *
	 * Requirements:
	 *
	 * - `sender` and `recipient` cannot be the zero address.
	 * - `sender` must have a balance of at least `amount`.
	 * - the caller must have allowance for ``sender``'s tokens of at least
	 * `amount`.
	 */
	function transferFrom(
		address sender,
		address recipient,
		uint256 amount
	) public virtual override returns (bool) {
		_transfer(sender, recipient, amount);

		uint256 currentAllowance = _allowances[sender][_msgSender()];
		require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
		unchecked {
			_approve(sender, _msgSender(), currentAllowance - amount);
		}

		return true;
	}

	/**
	 * @dev Atomically increases the allowance granted to `spender` by the caller.
	 *
	 * This is an alternative to {approve} that can be used as a mitigation for
	 * problems described in {IERC20-approve}.
	 *
	 * Emits an {Approval} event indicating the updated allowance.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 */
	function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
		_approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
		return true;
	}

	/**
	 * @dev Atomically decreases the allowance granted to `spender` by the caller.
	 *
	 * This is an alternative to {approve} that can be used as a mitigation for
	 * problems described in {IERC20-approve}.
	 *
	 * Emits an {Approval} event indicating the updated allowance.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 * - `spender` must have allowance for the caller of at least
	 * `subtractedValue`.
	 */
	function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
		uint256 currentAllowance = _allowances[_msgSender()][spender];
		require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
		unchecked {
			_approve(_msgSender(), spender, currentAllowance - subtractedValue);
		}

		return true;
	}

	/**
	 * @dev Moves `amount` of tokens from `sender` to `recipient`.
	 *
	 * This internal function is equivalent to {transfer}, and can be used to
	 * e.g. implement automatic token fees, slashing mechanisms, etc.
	 *
	 * Emits a {Transfer} event.
	 *
	 * Requirements:
	 *
	 * - `sender` cannot be the zero address.
	 * - `recipient` cannot be the zero address.
	 * - `sender` must have a balance of at least `amount`.
	 */
	function _transfer(
		address sender,
		address recipient,
		uint256 amount
	) internal virtual {
		require(sender != address(0), "ERC20: transfer from the zero address");
		require(recipient != address(0), "ERC20: transfer to the zero address");

		_beforeTokenTransfer(sender, recipient, amount);

		uint256 senderBalance = _balances[sender];
		require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
		unchecked {
			_balances[sender] = senderBalance - amount;
		}
		_balances[recipient] += amount;

		emit Transfer(sender, recipient, amount);

		_afterTokenTransfer(sender, recipient, amount);
	}

	/** @dev Creates `amount` tokens and assigns them to `account`, increasing
	 * the total supply.
	 *
	 * Emits a {Transfer} event with `from` set to the zero address.
	 *
	 * Requirements:
	 *
	 * - `account` cannot be the zero address.
	 */
	function _mint(address account, uint256 amount) internal virtual {
		require(account != address(0), "ERC20: mint to the zero address");

		_beforeTokenTransfer(address(0), account, amount);

		_totalSupply += amount;
		_balances[account] += amount;
		emit Transfer(address(0), account, amount);

		_afterTokenTransfer(address(0), account, amount);
	}

	/**
	 * @dev Destroys `amount` tokens from `account`, reducing the
	 * total supply.
	 *
	 * Emits a {Transfer} event with `to` set to the zero address.
	 *
	 * Requirements:
	 *
	 * - `account` cannot be the zero address.
	 * - `account` must have at least `amount` tokens.
	 */
	function _burn(address account, uint256 amount) internal virtual {
		require(account != address(0), "ERC20: burn from the zero address");

		_beforeTokenTransfer(account, address(0), amount);

		uint256 accountBalance = _balances[account];
		require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
		unchecked {
			_balances[account] = accountBalance - amount;
		}
		_totalSupply -= amount;

		emit Transfer(account, address(0), amount);

		_afterTokenTransfer(account, address(0), amount);
	}

	/**
	 * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
	 *
	 * This internal function is equivalent to `approve`, and can be used to
	 * e.g. set automatic allowances for certain subsystems, etc.
	 *
	 * Emits an {Approval} event.
	 *
	 * Requirements:
	 *
	 * - `owner` cannot be the zero address.
	 * - `spender` cannot be the zero address.
	 */
	function _approve(
		address owner,
		address spender,
		uint256 amount
	) internal virtual {
		require(owner != address(0), "ERC20: approve from the zero address");
		require(spender != address(0), "ERC20: approve to the zero address");

		_allowances[owner][spender] = amount;
		emit Approval(owner, spender, amount);
	}

	/**
	 * @dev Hook that is called before any transfer of tokens. This includes
	 * minting and burning.
	 *
	 * Calling conditions:
	 *
	 * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
	 * will be transferred to `to`.
	 * - when `from` is zero, `amount` tokens will be minted for `to`.
	 * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
	 * - `from` and `to` are never both zero.
	 *
	 * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
	 */
	function _beforeTokenTransfer(
		address from,
		address to,
		uint256 amount
	) internal virtual {}

	/**
	 * @dev Hook that is called after any transfer of tokens. This includes
	 * minting and burning.
	 *
	 * Calling conditions:
	 *
	 * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
	 * has been transferred to `to`.
	 * - when `from` is zero, `amount` tokens have been minted for `to`.
	 * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
	 * - `from` and `to` are never both zero.
	 *
	 * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
	 */
	function _afterTokenTransfer(
		address from,
		address to,
		uint256 amount
	) internal virtual {}
}

interface IMultiRewards {
	function balanceOf(address) external returns (uint256);

	function stakeFor(address, uint256) external;

	function withdrawFor(address, uint256) external;

	function notifyRewardAmount(address, uint256) external;

	function mintFor(address recipient, uint256 amount) external;

	function burnFrom(address _from, uint256 _amount) external;

	function stakeOf(address account) external view returns (uint256);
}

/**
 * @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;
		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");

		(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");

		(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");

		(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");

		(bool success, bytes memory returndata) = target.delegatecall(data);
		return verifyCallResult(success, returndata, errorMessage);
	}

	/**
	 * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
	 * revert reason using the provided one.
	 *
	 * _Available since v4.3._
	 */
	function verifyCallResult(
		bool success,
		bytes memory returndata,
		string memory errorMessage
	) internal 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

				assembly {
					let returndata_size := mload(returndata)
					revert(add(32, returndata), returndata_size)
				}
			} else {
				revert(errorMessage);
			}
		}
	}
}

/**
 * @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 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'
		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) + value;
		_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
	}

	function safeDecreaseAllowance(
		IERC20 token,
		address spender,
		uint256 value
	) internal {
		unchecked {
			uint256 oldAllowance = token.allowance(address(this), spender);
			require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
			uint256 newAllowance = oldAllowance - value;
			_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
			require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
		}
	}
}

interface ILocker {
	function createLock(uint256, uint256) external;

	function increaseAmount(uint256) external;

	function increaseUnlockTime(uint256) external;

	function release() external;

	function claimRewards(address, address) external;

	function claimFXSRewards(address) external;

	function execute(
		address,
		uint256,
		bytes calldata
	) external returns (bool, bytes memory);

	function setGovernance(address) external;

	function voteGaugeWeight(address, uint256) external;

	function setAngleDepositor(address) external;

	function setFxsDepositor(address) external;
}

contract BaseStrategy {
	/* ========== STATE VARIABLES ========== */
	ILocker locker;
	address public governance;
	address public rewardsReceiver;
	uint256 public veSDTFee;
	address public veSDTFeeProxy;
	uint256 public accumulatorFee;
	uint256 public claimerReward;
	uint256 public constant BASE_FEE = 10000;
	mapping(address => address) public gauges;
	mapping(address => bool) public vaults;
	mapping(address => uint256) public perfFee;
	mapping(address => address) public multiGauges;

	/* ========== EVENTS ========== */
	event Deposited(address _gauge, address _token, uint256 _amount);
	event Withdrawn(address _gauge, address _token, uint256 _amount);
	event Claimed(address _gauge, address _token, uint256 _amount);
	event VaultToggled(address _vault, bool _newState);
	event GaugeSet(address _gauge, address _token);

	/* ========== MODIFIERS ========== */
	modifier onlyGovernance() {
		require(msg.sender == governance, "!governance");
		_;
	}
	modifier onlyApprovedVault() {
		require(vaults[msg.sender], "!approved vault");
		_;
	}

	/* ========== CONSTRUCTOR ========== */
	constructor(
		ILocker _locker,
		address _governance,
		address _receiver
	) public {
		locker = _locker;
		governance = _governance;
		rewardsReceiver = _receiver;
	}

	/* ========== MUTATIVE FUNCTIONS ========== */
	function deposit(address _token, uint256 _amount) external virtual onlyApprovedVault {}

	function withdraw(address _token, uint256 _amount) external virtual onlyApprovedVault {}

	function claim(address _gauge) external virtual {}

	function toggleVault(address _vault) external virtual onlyGovernance {}

	function setGauge(address _token, address _gauge) external virtual onlyGovernance {}

	function setMultiGauge(address _gauge, address _multiGauge) external virtual onlyGovernance {}
}

interface ILiquidityGauge {
	struct Reward {
		address token;
		address distributor;
		uint256 period_finish;
		uint256 rate;
		uint256 last_update;
		uint256 integral;
	}

	// solhint-disable-next-line
	function deposit_reward_token(address _rewardToken, uint256 _amount) external;

	// solhint-disable-next-line
	function claim_rewards_for(address _user, address _recipient) external;

	// // solhint-disable-next-line
	// function claim_rewards_for(address _user) external;

	// solhint-disable-next-line
	function deposit(uint256 _value, address _addr) external;

	// solhint-disable-next-line
	function reward_tokens(uint256 _i) external view returns (address);

	// solhint-disable-next-line
	function reward_data(address _tokenReward) external view returns (Reward memory);

	function balanceOf(address) external returns (uint256);

	function claimable_reward(address _user, address _reward_token) external view returns (uint256);

	function user_checkpoint(address _user) external returns (bool);
}

/// @title A contract that defines the functions shared by all accumulators
/// @author StakeDAO
contract BaseAccumulator {
	using SafeERC20 for IERC20;
	/* ========== STATE VARIABLES ========== */
	address public governance;
	address public locker;
	address public tokenReward;
	address public gauge;

	/* ========== EVENTS ========== */
	event GaugeSet(address oldGauge, address newGauge);
	event RewardNotified(address gauge, address tokenReward, uint256 amount);
	event LockerSet(address oldLocker, address newLocker);
	event GovernanceSet(address oldGov, address newGov);
	event TokenRewardSet(address oldTr, address newTr);
	event TokenDeposited(address token, uint256 amount);
	event ERC20Rescued(address token, uint256 amount);

	/* ========== CONSTRUCTOR ========== */
	constructor(address _tokenReward) {
		tokenReward = _tokenReward;
		governance = msg.sender;
	}

	/* ========== MUTATIVE FUNCTIONS ========== */

	/// @notice Notify the reward using an extra token
	/// @param _tokenReward token address to notify
	/// @param _amount amount to notify
	function notifyExtraReward(address _tokenReward, uint256 _amount) external {
		require(msg.sender == governance, "!gov");
		_notifyReward(_tokenReward, _amount);
	}

	/// @notice Notify the reward using all balance of extra token
	/// @param _tokenReward token address to notify
	function notifyAllExtraReward(address _tokenReward) external {
		require(msg.sender == governance, "!gov");
		uint256 amount = IERC20(_tokenReward).balanceOf(address(this));
		_notifyReward(_tokenReward, amount);
	}

	/// @notice Notify the new reward to the LGV4
	/// @param _tokenReward token to notify
	/// @param _amount amount to notify
	function _notifyReward(address _tokenReward, uint256 _amount) internal {
		require(gauge != address(0), "gauge not set");
		require(_amount > 0, "set an amount > 0");
		uint256 balanceBefore = IERC20(_tokenReward).balanceOf(address(this));
		require(balanceBefore >= _amount, "amount not enough");
		if (ILiquidityGauge(gauge).reward_data(_tokenReward).distributor != address(0)) {
			IERC20(_tokenReward).approve(gauge, _amount);
			ILiquidityGauge(gauge).deposit_reward_token(_tokenReward, _amount);
			uint256 balanceAfter = IERC20(_tokenReward).balanceOf(address(this));
			require(balanceBefore - balanceAfter == _amount, "wrong amount notified");
			emit RewardNotified(gauge, _tokenReward, _amount);
		}
	}

	/// @notice Deposit token into the accumulator
	/// @param _token token to deposit
	/// @param _amount amount to deposit
	function depositToken(address _token, uint256 _amount) external {
		require(_amount > 0, "set an amount > 0");
		IERC20(_token).safeTransferFrom(msg.sender, address(this), _amount);
		emit TokenDeposited(_token, _amount);
	}

	/// @notice Sets gauge for the accumulator which will receive and distribute the rewards
	/// @dev Can be called only by the governance
	/// @param _gauge gauge address
	function setGauge(address _gauge) external {
		require(msg.sender == governance, "!gov");
		require(_gauge != address(0), "can't be zero address");
		emit GaugeSet(gauge, _gauge);
		gauge = _gauge;
	}

	/// @notice Allows the governance to set the new governance
	/// @dev Can be called only by the governance
	/// @param _governance governance address
	function setGovernance(address _governance) external {
		require(msg.sender == governance, "!gov");
		require(_governance != address(0), "can't be zero address");
		emit GovernanceSet(governance, _governance);
		governance = _governance;
	}

	/// @notice Allows the governance to set the locker
	/// @dev Can be called only by the governance
	/// @param _locker locker address
	function setLocker(address _locker) external {
		require(msg.sender == governance, "!gov");
		require(_locker != address(0), "can't be zero address");
		emit LockerSet(locker, _locker);
		locker = _locker;
	}

	/// @notice Allows the governance to set the token reward
	/// @dev Can be called only by the governance
	/// @param _tokenReward token reward address
	function setTokenReward(address _tokenReward) external {
		require(msg.sender == governance, "!gov");
		require(_tokenReward != address(0), "can't be zero address");
		emit TokenRewardSet(tokenReward, _tokenReward);
		tokenReward = _tokenReward;
	}

	/// @notice A function that rescue any ERC20 token
	/// @param _token token address
	/// @param _amount amount to rescue
	/// @param _recipient address to send token rescued
	function rescueERC20(
		address _token,
		uint256 _amount,
		address _recipient
	) external {
		require(msg.sender == governance, "!gov");
		require(_amount > 0, "set an amount > 0");
		require(_recipient != address(0), "can't be zero address");
		IERC20(_token).safeTransfer(_recipient, _amount);
		emit ERC20Rescued(_token, _amount);
	}
}

/// @title A contract that accumulates sanUSDC_EUR rewards and notifies them to the LGV4
/// @author StakeDAO
contract AngleAccumulator is BaseAccumulator {
	/* ========== CONSTRUCTOR ========== */
	constructor(address _tokenReward) BaseAccumulator(_tokenReward) {}

	/* ========== MUTATIVE FUNCTIONS ========== */
	/// @notice Claims rewards from the locker and notify an amount to the LGV4
	/// @param _amount amount to notify after the claim
	function claimAndNotify(uint256 _amount) external {
		require(locker != address(0), "locker not set");
		ILocker(locker).claimRewards(tokenReward, address(this));
		_notifyReward(tokenReward, _amount);
	}

	/// @notice Claims rewards from the locker and notify all to the LGV4
	function claimAndNotifyAll() external {
		require(locker != address(0), "locker not set");
		ILocker(locker).claimRewards(tokenReward, address(this));
		uint256 amount = IERC20(tokenReward).balanceOf(address(this));
		_notifyReward(tokenReward, amount);
	}
}

contract AngleStrategy is BaseStrategy {
	using SafeERC20 for IERC20;
	AngleAccumulator public accumulator;
	struct ClaimerReward {
		address rewardToken;
		uint256 amount;
	}
	enum MANAGEFEE {
		PERFFEE,
		VESDTFEE,
		ACCUMULATORFEE,
		CLAIMERREWARD
	}

	/* ========== CONSTRUCTOR ========== */
	constructor(
		ILocker _locker,
		address _governance,
		address _receiver,
		AngleAccumulator _accumulator,
		address _veSDTFeeProxy
	) BaseStrategy(_locker, _governance, _receiver) {
		veSDTFee = 500; // %5
		accumulatorFee = 800; // %8
		claimerReward = 50; //%0.5
		accumulator = _accumulator;
		veSDTFeeProxy = _veSDTFeeProxy;
	}

	/* ========== MUTATIVE FUNCTIONS ========== */
	function deposit(address _token, uint256 _amount) public override onlyApprovedVault {
		IERC20(_token).transferFrom(msg.sender, address(locker), _amount);
		address gauge = gauges[_token];
		require(gauge != address(0), "!gauge");
		locker.execute(_token, 0, abi.encodeWithSignature("approve(address,uint256)", gauge, 0));
		locker.execute(_token, 0, abi.encodeWithSignature("approve(address,uint256)", gauge, _amount));

		(bool success, ) = locker.execute(gauge, 0, abi.encodeWithSignature("deposit(uint256)", _amount));
		require(success, "Deposit failed!");
		emit Deposited(gauge, _token, _amount);
	}

	function withdraw(address _token, uint256 _amount) public override onlyApprovedVault {
		uint256 _before = IERC20(_token).balanceOf(address(locker));
		address gauge = gauges[_token];
		require(gauge != address(0), "!gauge");
		(bool success, ) = locker.execute(gauge, 0, abi.encodeWithSignature("withdraw(uint256)", _amount));
		require(success, "Transfer failed!");
		uint256 _after = IERC20(_token).balanceOf(address(locker));

		uint256 _net = _after - _before;
		(success, ) = locker.execute(_token, 0, abi.encodeWithSignature("transfer(address,uint256)", msg.sender, _net));
		require(success, "Transfer failed!");
		emit Withdrawn(gauge, _token, _amount);
	}

	function claim(address _token) external override {
		address gauge = gauges[_token];
		require(gauge != address(0), "!gauge");
		(bool success, ) = locker.execute(gauge, 0, abi.encodeWithSignature("user_checkpoint(address)", address(locker)));
		require(success, "Checkpoint failed!");
		(success, ) = locker.execute(
			gauge,
			0,
			abi.encodeWithSignature("claim_rewards(address,address)", address(locker), address(this))
		);
		require(success, "Claim failed!");
		for (uint8 i = 0; i < 8; i++) {
			address rewardToken = ILiquidityGauge(gauge).reward_tokens(i);
			if (rewardToken == address(0)) {
				break;
			}
			uint256 rewardsBalance = IERC20(rewardToken).balanceOf(address(this));
			uint256 multisigFee = (rewardsBalance * perfFee[gauge]) / BASE_FEE;
			uint256 accumulatorPart = (rewardsBalance * accumulatorFee) / BASE_FEE;
			uint256 veSDTPart = (rewardsBalance * veSDTFee) / BASE_FEE;
			uint256 claimerPart = (rewardsBalance * claimerReward) / BASE_FEE;
			IERC20(rewardToken).approve(address(accumulator), accumulatorPart);
			accumulator.depositToken(rewardToken, accumulatorPart);
			IERC20(rewardToken).transfer(rewardsReceiver, multisigFee);
			IERC20(rewardToken).transfer(veSDTFeeProxy, veSDTPart);
			IERC20(rewardToken).transfer(msg.sender, claimerPart);
			uint256 netRewards = rewardsBalance - multisigFee - accumulatorPart - veSDTPart - claimerPart;
			IERC20(rewardToken).approve(multiGauges[gauge], netRewards);
			IMultiRewards(multiGauges[gauge]).notifyRewardAmount(rewardToken, netRewards);
			emit Claimed(gauge, rewardToken, rewardsBalance);
		}
	}

	function claimerPendingRewards(address _token) external view returns (ClaimerReward[] memory) {
		ClaimerReward[] memory pendings = new ClaimerReward[](8);
		address gauge = gauges[_token];
		for (uint8 i = 0; i < 8; i++) {
			address rewardToken = ILiquidityGauge(gauge).reward_tokens(i);
			if (rewardToken == address(0)) {
				break;
			}
			uint256 rewardsBalance = ILiquidityGauge(gauge).claimable_reward(address(locker), rewardToken);
			uint256 pendingAmount = (rewardsBalance * claimerReward) / BASE_FEE;
			ClaimerReward memory pendingReward = ClaimerReward(rewardToken, pendingAmount);
			pendings[i] = pendingReward;
		}
		return pendings;
	}

	function toggleVault(address _vault) external override onlyGovernance {
		vaults[_vault] = !vaults[_vault];
		emit VaultToggled(_vault, vaults[_vault]);
	}

	function setGauge(address _token, address _gauge) external override onlyGovernance {
		gauges[_token] = _gauge;
		emit GaugeSet(_gauge, _token);
	}

	function setMultiGauge(address _gauge, address _multiGauge) external override onlyGovernance {
		multiGauges[_gauge] = _multiGauge;
	}

	function setVeSDTProxy(address _newVeSDTProxy) external onlyGovernance {
		veSDTFeeProxy = _newVeSDTProxy;
	}

	function setAccumulator(address _newAccumulator) external onlyGovernance {
		accumulator = AngleAccumulator(_newAccumulator);
	}

	function setRewardsReceiver(address _newRewardsReceiver) external onlyGovernance {
		rewardsReceiver = _newRewardsReceiver;
	}

	function setGovernance(address _newGovernance) external onlyGovernance {
		governance = _newGovernance;
	}

	function manageFee(
		MANAGEFEE _manageFee,
		address _gauge,
		uint256 _newFee
	) external onlyGovernance {
		if (_manageFee == MANAGEFEE.PERFFEE) {
			// 0
			require(_gauge != address(0), "zero address");
			perfFee[_gauge] = _newFee;
		} else if (_manageFee == MANAGEFEE.VESDTFEE) {
			// 1
			veSDTFee = _newFee;
		} else if (_manageFee == MANAGEFEE.ACCUMULATORFEE) {
			//2
			accumulatorFee = _newFee;
		} else if (_manageFee == MANAGEFEE.CLAIMERREWARD) {
			// 3
			claimerReward = _newFee;
		}
	}

	/// @notice execute a function
	/// @param to Address to sent the value to
	/// @param value Value to be sent
	/// @param data Call function data
	function execute(
		address to,
		uint256 value,
		bytes calldata data
	) external onlyGovernance returns (bool, bytes memory) {
		(bool success, bytes memory result) = to.call{ value: value }(data);
		return (success, result);
	}
}

contract AngleVault is ERC20Upgradeable {
	using SafeERC20Upgradeable for ERC20Upgradeable;
	using AddressUpgradeable for address;

	ERC20Upgradeable public token;
	address public governance;
	uint256 public withdrawalFee;
	address public multiRewardsGauge;
	AngleStrategy public angleStrategy;
	uint256 public min;
	uint256 public constant max = 10000;
	event Earn(address _token, uint256 _amount);
	event Deposit(address _depositor, uint256 _amount);
	event Withdraw(address _depositor, uint256 _amount);

	function init(
		ERC20Upgradeable _token,
		address _governance,
		string memory name_,
		string memory symbol_,
		AngleStrategy _angleStrategy
	) public initializer {
		__ERC20_init(name_, symbol_);
		token = _token;
		governance = _governance;
		withdrawalFee = 50; // %0.5
		min = 10000;
		angleStrategy = _angleStrategy;
	}

	function deposit(uint256 _amount) public {
		require(address(multiRewardsGauge) != address(0), "Gauge not yet initialized");
		token.safeTransferFrom(msg.sender, address(this), _amount);
		_mint(address(this), _amount);
		ERC20Upgradeable(address(this)).approve(multiRewardsGauge, _amount);
		IMultiRewards(multiRewardsGauge).stakeFor(msg.sender, _amount);
		IMultiRewards(multiRewardsGauge).mintFor(msg.sender, _amount);
		emit Deposit(msg.sender, _amount);
	}

	function depositAll() external {
		deposit(token.balanceOf(msg.sender));
	}

	function withdraw(uint256 _shares) public {
		uint256 userTotalShares = IMultiRewards(multiRewardsGauge).stakeOf(msg.sender);
		require(_shares <= userTotalShares, "Not enough staked");
		IMultiRewards(multiRewardsGauge).withdrawFor(msg.sender, _shares);
		_burn(address(this), _shares);
		uint256 tokenBalance = token.balanceOf(address(this));
		uint256 withdrawFee;
		if (_shares > tokenBalance) {
			uint256 amountToWithdraw = _shares - tokenBalance;
			angleStrategy.withdraw(address(token), amountToWithdraw);
			withdrawFee = (amountToWithdraw * withdrawalFee) / 10000;
			token.safeTransfer(governance, withdrawFee);
		}
		IMultiRewards(multiRewardsGauge).burnFrom(msg.sender, _shares);
		token.safeTransfer(msg.sender, _shares - withdrawFee);
		emit Withdraw(msg.sender, _shares - withdrawFee);
	}

	function withdrawAll() external {
		withdraw(balanceOf(msg.sender));
	}

	function setGovernance(address _governance) external {
		require(msg.sender == governance, "!governance");
		governance = _governance;
	}

	function setGaugeMultiRewards(address _multiRewardsGauge) external {
		require(msg.sender == governance, "!governance");
		multiRewardsGauge = _multiRewardsGauge;
	}

	function setAngleStrategy(AngleStrategy _newStrat) external {
		require(msg.sender == governance, "!governance");
		angleStrategy = _newStrat;
	}

	function decimals() public view override returns (uint8) {
		return token.decimals();
	}

	function setWithdrawnFee(uint256 _newFee) external {
		require(msg.sender == governance, "!governance");
		withdrawalFee = _newFee;
	}

	function setMin(uint256 _min) external {
		require(msg.sender == governance, "!governance");
		min = _min;
	}

	function available() public view returns (uint256) {
		return (token.balanceOf(address(this)) * min) / max;
	}

	function earn() external {
		uint256 tokenBalance = available();
		token.increaseAllowance(address(angleStrategy), tokenBalance);
		angleStrategy.deposit(address(token), tokenBalance);
		emit Earn(address(token), tokenBalance);
	}
}