creation_sourcecode: // SPDX-License-Identifier: GPL-3.0
  pragma solidity 0.8.18;
  
  // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)
  
  // OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
  
  /**
   * @dev Interface of the ERC20 standard as defined in the EIP.
   */
  interface IERC20 {
      /**
       * @dev Emitted when `value` tokens are moved from one account (`from`) to
       * another (`to`).
       *
       * Note that `value` may be zero.
       */
      event Transfer(address indexed from, address indexed to, uint256 value);
  
      /**
       * @dev Emitted when the allowance of a `spender` for an `owner` is set by
       * a call to {approve}. `value` is the new allowance.
       */
      event Approval(address indexed owner, address indexed spender, uint256 value);
  
      /**
       * @dev Returns the amount of tokens in existence.
       */
      function totalSupply() external view returns (uint256);
  
      /**
       * @dev Returns the amount of tokens owned by `account`.
       */
      function balanceOf(address account) external view returns (uint256);
  
      /**
       * @dev Moves `amount` tokens from the caller's account to `to`.
       *
       * Returns a boolean value indicating whether the operation succeeded.
       *
       * Emits a {Transfer} event.
       */
      function transfer(address to, uint256 amount) external returns (bool);
  
      /**
       * @dev Returns the remaining number of tokens that `spender` will be
       * allowed to spend on behalf of `owner` through {transferFrom}. This is
       * zero by default.
       *
       * This value changes when {approve} or {transferFrom} are called.
       */
      function allowance(address owner, address spender) external view returns (uint256);
  
      /**
       * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
       *
       * Returns a boolean value indicating whether the operation succeeded.
       *
       * IMPORTANT: Beware that changing an allowance with this method brings the risk
       * that someone may use both the old and the new allowance by unfortunate
       * transaction ordering. One possible solution to mitigate this race
       * condition is to first reduce the spender's allowance to 0 and set the
       * desired value afterwards:
       * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
       *
       * Emits an {Approval} event.
       */
      function approve(address spender, uint256 amount) external returns (bool);
  
      /**
       * @dev Moves `amount` tokens from `from` to `to` using the
       * allowance mechanism. `amount` is then deducted from the caller's
       * allowance.
       *
       * Returns a boolean value indicating whether the operation succeeded.
       *
       * Emits a {Transfer} event.
       */
      function transferFrom(address from, address to, uint256 amount) external returns (bool);
  }
  
  // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
  
  /**
   * @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);
  }
  
  // OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)
  
  /**
   * @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;
      }
  
      function _contextSuffixLength() internal view virtual returns (uint256) {
          return 0;
      }
  }
  
  /**
   * @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.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
   * to implement supply mechanisms].
   *
   * The default value of {decimals} is 18. To change this, you should override
   * this function so it returns a different value.
   *
   * 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}.
       *
       * 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 default value returned by this function, unless
       * it's 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:
       *
       * - `to` cannot be the zero address.
       * - the caller must have a balance of at least `amount`.
       */
      function transfer(address to, uint256 amount) public virtual override returns (bool) {
          address owner = _msgSender();
          _transfer(owner, to, 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}.
       *
       * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
       * `transferFrom`. This is semantically equivalent to an infinite approval.
       *
       * Requirements:
       *
       * - `spender` cannot be the zero address.
       */
      function approve(address spender, uint256 amount) public virtual override returns (bool) {
          address owner = _msgSender();
          _approve(owner, 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}.
       *
       * NOTE: Does not update the allowance if the current allowance
       * is the maximum `uint256`.
       *
       * Requirements:
       *
       * - `from` and `to` cannot be the zero address.
       * - `from` must have a balance of at least `amount`.
       * - the caller must have allowance for ``from``'s tokens of at least
       * `amount`.
       */
      function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
          address spender = _msgSender();
          _spendAllowance(from, spender, amount);
          _transfer(from, to, 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) {
          address owner = _msgSender();
          _approve(owner, spender, allowance(owner, 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) {
          address owner = _msgSender();
          uint256 currentAllowance = allowance(owner, spender);
          require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
          unchecked {
              _approve(owner, spender, currentAllowance - subtractedValue);
          }
  
          return true;
      }
  
      /**
       * @dev Moves `amount` of tokens from `from` to `to`.
       *
       * 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:
       *
       * - `from` cannot be the zero address.
       * - `to` cannot be the zero address.
       * - `from` must have a balance of at least `amount`.
       */
      function _transfer(address from, address to, uint256 amount) internal virtual {
          require(from != address(0), "ERC20: transfer from the zero address");
          require(to != address(0), "ERC20: transfer to the zero address");
  
          _beforeTokenTransfer(from, to, amount);
  
          uint256 fromBalance = _balances[from];
          require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
          unchecked {
              _balances[from] = fromBalance - amount;
              // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
              // decrementing then incrementing.
              _balances[to] += amount;
          }
  
          emit Transfer(from, to, amount);
  
          _afterTokenTransfer(from, to, 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;
          unchecked {
              // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
              _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;
              // Overflow not possible: amount <= accountBalance <= totalSupply.
              _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 Updates `owner` s allowance for `spender` based on spent `amount`.
       *
       * Does not update the allowance amount in case of infinite allowance.
       * Revert if not enough allowance is available.
       *
       * Might emit an {Approval} event.
       */
      function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
          uint256 currentAllowance = allowance(owner, spender);
          if (currentAllowance != type(uint256).max) {
              require(currentAllowance >= amount, "ERC20: insufficient allowance");
              unchecked {
                  _approve(owner, spender, currentAllowance - 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 {}
  }
  
  // TokenizedStrategy interface used for internal view delegateCalls.
  
  // OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC4626.sol)
  
  /**
   * @dev Interface of the ERC4626 "Tokenized Vault Standard", as defined in
   * https://eips.ethereum.org/EIPS/eip-4626[ERC-4626].
   *
   * _Available since v4.7._
   */
  interface IERC4626 is IERC20, IERC20Metadata {
      event Deposit(address indexed sender, address indexed owner, uint256 assets, uint256 shares);
  
      event Withdraw(
          address indexed sender,
          address indexed receiver,
          address indexed owner,
          uint256 assets,
          uint256 shares
      );
  
      /**
       * @dev Returns the address of the underlying token used for the Vault for accounting, depositing, and withdrawing.
       *
       * - MUST be an ERC-20 token contract.
       * - MUST NOT revert.
       */
      function asset() external view returns (address assetTokenAddress);
  
      /**
       * @dev Returns the total amount of the underlying asset that is “managed” by Vault.
       *
       * - SHOULD include any compounding that occurs from yield.
       * - MUST be inclusive of any fees that are charged against assets in the Vault.
       * - MUST NOT revert.
       */
      function totalAssets() external view returns (uint256 totalManagedAssets);
  
      /**
       * @dev Returns the amount of shares that the Vault would exchange for the amount of assets provided, in an ideal
       * scenario where all the conditions are met.
       *
       * - MUST NOT be inclusive of any fees that are charged against assets in the Vault.
       * - MUST NOT show any variations depending on the caller.
       * - MUST NOT reflect slippage or other on-chain conditions, when performing the actual exchange.
       * - MUST NOT revert.
       *
       * NOTE: This calculation MAY NOT reflect the “per-user” price-per-share, and instead should reflect the
       * “average-user’s” price-per-share, meaning what the average user should expect to see when exchanging to and
       * from.
       */
      function convertToShares(uint256 assets) external view returns (uint256 shares);
  
      /**
       * @dev Returns the amount of assets that the Vault would exchange for the amount of shares provided, in an ideal
       * scenario where all the conditions are met.
       *
       * - MUST NOT be inclusive of any fees that are charged against assets in the Vault.
       * - MUST NOT show any variations depending on the caller.
       * - MUST NOT reflect slippage or other on-chain conditions, when performing the actual exchange.
       * - MUST NOT revert.
       *
       * NOTE: This calculation MAY NOT reflect the “per-user” price-per-share, and instead should reflect the
       * “average-user’s” price-per-share, meaning what the average user should expect to see when exchanging to and
       * from.
       */
      function convertToAssets(uint256 shares) external view returns (uint256 assets);
  
      /**
       * @dev Returns the maximum amount of the underlying asset that can be deposited into the Vault for the receiver,
       * through a deposit call.
       *
       * - MUST return a limited value if receiver is subject to some deposit limit.
       * - MUST return 2 ** 256 - 1 if there is no limit on the maximum amount of assets that may be deposited.
       * - MUST NOT revert.
       */
      function maxDeposit(address receiver) external view returns (uint256 maxAssets);
  
      /**
       * @dev Allows an on-chain or off-chain user to simulate the effects of their deposit at the current block, given
       * current on-chain conditions.
       *
       * - MUST return as close to and no more than the exact amount of Vault shares that would be minted in a deposit
       *   call in the same transaction. I.e. deposit should return the same or more shares as previewDeposit if called
       *   in the same transaction.
       * - MUST NOT account for deposit limits like those returned from maxDeposit and should always act as though the
       *   deposit would be accepted, regardless if the user has enough tokens approved, etc.
       * - MUST be inclusive of deposit fees. Integrators should be aware of the existence of deposit fees.
       * - MUST NOT revert.
       *
       * NOTE: any unfavorable discrepancy between convertToShares and previewDeposit SHOULD be considered slippage in
       * share price or some other type of condition, meaning the depositor will lose assets by depositing.
       */
      function previewDeposit(uint256 assets) external view returns (uint256 shares);
  
      /**
       * @dev Mints shares Vault shares to receiver by depositing exactly amount of underlying tokens.
       *
       * - MUST emit the Deposit event.
       * - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
       *   deposit execution, and are accounted for during deposit.
       * - MUST revert if all of assets cannot be deposited (due to deposit limit being reached, slippage, the user not
       *   approving enough underlying tokens to the Vault contract, etc).
       *
       * NOTE: most implementations will require pre-approval of the Vault with the Vault’s underlying asset token.
       */
      function deposit(uint256 assets, address receiver) external returns (uint256 shares);
  
      /**
       * @dev Returns the maximum amount of the Vault shares that can be minted for the receiver, through a mint call.
       * - MUST return a limited value if receiver is subject to some mint limit.
       * - MUST return 2 ** 256 - 1 if there is no limit on the maximum amount of shares that may be minted.
       * - MUST NOT revert.
       */
      function maxMint(address receiver) external view returns (uint256 maxShares);
  
      /**
       * @dev Allows an on-chain or off-chain user to simulate the effects of their mint at the current block, given
       * current on-chain conditions.
       *
       * - MUST return as close to and no fewer than the exact amount of assets that would be deposited in a mint call
       *   in the same transaction. I.e. mint should return the same or fewer assets as previewMint if called in the
       *   same transaction.
       * - MUST NOT account for mint limits like those returned from maxMint and should always act as though the mint
       *   would be accepted, regardless if the user has enough tokens approved, etc.
       * - MUST be inclusive of deposit fees. Integrators should be aware of the existence of deposit fees.
       * - MUST NOT revert.
       *
       * NOTE: any unfavorable discrepancy between convertToAssets and previewMint SHOULD be considered slippage in
       * share price or some other type of condition, meaning the depositor will lose assets by minting.
       */
      function previewMint(uint256 shares) external view returns (uint256 assets);
  
      /**
       * @dev Mints exactly shares Vault shares to receiver by depositing amount of underlying tokens.
       *
       * - MUST emit the Deposit event.
       * - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the mint
       *   execution, and are accounted for during mint.
       * - MUST revert if all of shares cannot be minted (due to deposit limit being reached, slippage, the user not
       *   approving enough underlying tokens to the Vault contract, etc).
       *
       * NOTE: most implementations will require pre-approval of the Vault with the Vault’s underlying asset token.
       */
      function mint(uint256 shares, address receiver) external returns (uint256 assets);
  
      /**
       * @dev Returns the maximum amount of the underlying asset that can be withdrawn from the owner balance in the
       * Vault, through a withdraw call.
       *
       * - MUST return a limited value if owner is subject to some withdrawal limit or timelock.
       * - MUST NOT revert.
       */
      function maxWithdraw(address owner) external view returns (uint256 maxAssets);
  
      /**
       * @dev Allows an on-chain or off-chain user to simulate the effects of their withdrawal at the current block,
       * given current on-chain conditions.
       *
       * - MUST return as close to and no fewer than the exact amount of Vault shares that would be burned in a withdraw
       *   call in the same transaction. I.e. withdraw should return the same or fewer shares as previewWithdraw if
       *   called
       *   in the same transaction.
       * - MUST NOT account for withdrawal limits like those returned from maxWithdraw and should always act as though
       *   the withdrawal would be accepted, regardless if the user has enough shares, etc.
       * - MUST be inclusive of withdrawal fees. Integrators should be aware of the existence of withdrawal fees.
       * - MUST NOT revert.
       *
       * NOTE: any unfavorable discrepancy between convertToShares and previewWithdraw SHOULD be considered slippage in
       * share price or some other type of condition, meaning the depositor will lose assets by depositing.
       */
      function previewWithdraw(uint256 assets) external view returns (uint256 shares);
  
      /**
       * @dev Burns shares from owner and sends exactly assets of underlying tokens to receiver.
       *
       * - MUST emit the Withdraw event.
       * - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
       *   withdraw execution, and are accounted for during withdraw.
       * - MUST revert if all of assets cannot be withdrawn (due to withdrawal limit being reached, slippage, the owner
       *   not having enough shares, etc).
       *
       * Note that some implementations will require pre-requesting to the Vault before a withdrawal may be performed.
       * Those methods should be performed separately.
       */
      function withdraw(uint256 assets, address receiver, address owner) external returns (uint256 shares);
  
      /**
       * @dev Returns the maximum amount of Vault shares that can be redeemed from the owner balance in the Vault,
       * through a redeem call.
       *
       * - MUST return a limited value if owner is subject to some withdrawal limit or timelock.
       * - MUST return balanceOf(owner) if owner is not subject to any withdrawal limit or timelock.
       * - MUST NOT revert.
       */
      function maxRedeem(address owner) external view returns (uint256 maxShares);
  
      /**
       * @dev Allows an on-chain or off-chain user to simulate the effects of their redeemption at the current block,
       * given current on-chain conditions.
       *
       * - MUST return as close to and no more than the exact amount of assets that would be withdrawn in a redeem call
       *   in the same transaction. I.e. redeem should return the same or more assets as previewRedeem if called in the
       *   same transaction.
       * - MUST NOT account for redemption limits like those returned from maxRedeem and should always act as though the
       *   redemption would be accepted, regardless if the user has enough shares, etc.
       * - MUST be inclusive of withdrawal fees. Integrators should be aware of the existence of withdrawal fees.
       * - MUST NOT revert.
       *
       * NOTE: any unfavorable discrepancy between convertToAssets and previewRedeem SHOULD be considered slippage in
       * share price or some other type of condition, meaning the depositor will lose assets by redeeming.
       */
      function previewRedeem(uint256 shares) external view returns (uint256 assets);
  
      /**
       * @dev Burns exactly shares from owner and sends assets of underlying tokens to receiver.
       *
       * - MUST emit the Withdraw event.
       * - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
       *   redeem execution, and are accounted for during redeem.
       * - MUST revert if all of shares cannot be redeemed (due to withdrawal limit being reached, slippage, the owner
       *   not having enough shares, etc).
       *
       * NOTE: some implementations will require pre-requesting to the Vault before a withdrawal may be performed.
       * Those methods should be performed separately.
       */
      function redeem(uint256 shares, address receiver, address owner) external returns (uint256 assets);
  }
  
  // OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)
  
  /**
   * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
   * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
   *
   * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
   * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
   * need to send a transaction, and thus is not required to hold Ether at all.
   *
   * ==== Security Considerations
   *
   * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
   * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
   * considered as an intention to spend the allowance in any specific way. The second is that because permits have
   * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
   * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
   * generally recommended is:
   *
   * ```solidity
   * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
   *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
   *     doThing(..., value);
   * }
   *
   * function doThing(..., uint256 value) public {
   *     token.safeTransferFrom(msg.sender, address(this), value);
   *     ...
   * }
   * ```
   *
   * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
   * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
   * {SafeERC20-safeTransferFrom}).
   *
   * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
   * contracts should have entry points that don't rely on permit.
   */
  interface IERC20Permit {
      /**
       * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
       * given ``owner``'s signed approval.
       *
       * IMPORTANT: The same issues {IERC20-approve} has related to transaction
       * ordering also apply here.
       *
       * Emits an {Approval} event.
       *
       * Requirements:
       *
       * - `spender` cannot be the zero address.
       * - `deadline` must be a timestamp in the future.
       * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
       * over the EIP712-formatted function arguments.
       * - the signature must use ``owner``'s current nonce (see {nonces}).
       *
       * For more information on the signature format, see the
       * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
       * section].
       *
       * CAUTION: See Security Considerations above.
       */
      function permit(
          address owner,
          address spender,
          uint256 value,
          uint256 deadline,
          uint8 v,
          bytes32 r,
          bytes32 s
      ) external;
  
      /**
       * @dev Returns the current nonce for `owner`. This value must be
       * included whenever a signature is generated for {permit}.
       *
       * Every successful call to {permit} increases ``owner``'s nonce by one. This
       * prevents a signature from being used multiple times.
       */
      function nonces(address owner) external view returns (uint256);
  
      /**
       * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
       */
      // solhint-disable-next-line func-name-mixedcase
      function DOMAIN_SEPARATOR() external view returns (bytes32);
  }
  
  // Interface that implements the 4626 standard and the implementation functions
  interface ITokenizedStrategy is IERC4626, IERC20Permit {
      /*//////////////////////////////////////////////////////////////
                                   EVENTS
      //////////////////////////////////////////////////////////////*/
  
      event StrategyShutdown();
  
      event NewTokenizedStrategy(
          address indexed strategy,
          address indexed asset,
          string apiVersion
      );
  
      event Reported(
          uint256 profit,
          uint256 loss,
          uint256 protocolFees,
          uint256 performanceFees
      );
  
      event UpdatePerformanceFeeRecipient(
          address indexed newPerformanceFeeRecipient
      );
  
      event UpdateKeeper(address indexed newKeeper);
  
      event UpdatePerformanceFee(uint16 newPerformanceFee);
  
      event UpdateManagement(address indexed newManagement);
  
      event UpdateEmergencyAdmin(address indexed newEmergencyAdmin);
  
      event UpdateProfitMaxUnlockTime(uint256 newProfitMaxUnlockTime);
  
      event UpdatePendingManagement(address indexed newPendingManagement);
  
      /*//////////////////////////////////////////////////////////////
                             INITIALIZATION
      //////////////////////////////////////////////////////////////*/
  
      function initialize(
          address _asset,
          string memory _name,
          address _management,
          address _performanceFeeRecipient,
          address _keeper
      ) external;
  
      /*//////////////////////////////////////////////////////////////
                      NON-STANDARD 4626 OPTIONS
      //////////////////////////////////////////////////////////////*/
  
      function withdraw(
          uint256 assets,
          address receiver,
          address owner,
          uint256 maxLoss
      ) external returns (uint256);
  
      function redeem(
          uint256 shares,
          address receiver,
          address owner,
          uint256 maxLoss
      ) external returns (uint256);
  
      /*//////////////////////////////////////////////////////////////
                          MODIFIER HELPERS
      //////////////////////////////////////////////////////////////*/
  
      function requireManagement(address _sender) external view;
  
      function requireKeeperOrManagement(address _sender) external view;
  
      function requireEmergencyAuthorized(address _sender) external view;
  
      /*//////////////////////////////////////////////////////////////
                          KEEPERS FUNCTIONS
      //////////////////////////////////////////////////////////////*/
  
      function tend() external;
  
      function report() external returns (uint256 _profit, uint256 _loss);
  
      /*//////////////////////////////////////////////////////////////
                          CONSTANTS
      //////////////////////////////////////////////////////////////*/
  
      function MAX_FEE() external view returns (uint16);
  
      function FACTORY() external view returns (address);
  
      /*//////////////////////////////////////////////////////////////
                              GETTERS
      //////////////////////////////////////////////////////////////*/
  
      function apiVersion() external view returns (string memory);
  
      function pricePerShare() external view returns (uint256);
  
      function management() external view returns (address);
  
      function pendingManagement() external view returns (address);
  
      function keeper() external view returns (address);
  
      function emergencyAdmin() external view returns (address);
  
      function performanceFee() external view returns (uint16);
  
      function performanceFeeRecipient() external view returns (address);
  
      function fullProfitUnlockDate() external view returns (uint256);
  
      function profitUnlockingRate() external view returns (uint256);
  
      function profitMaxUnlockTime() external view returns (uint256);
  
      function lastReport() external view returns (uint256);
  
      function isShutdown() external view returns (bool);
  
      function unlockedShares() external view returns (uint256);
  
      /*//////////////////////////////////////////////////////////////
                              SETTERS
      //////////////////////////////////////////////////////////////*/
  
      function setPendingManagement(address) external;
  
      function acceptManagement() external;
  
      function setKeeper(address _keeper) external;
  
      function setEmergencyAdmin(address _emergencyAdmin) external;
  
      function setPerformanceFee(uint16 _performanceFee) external;
  
      function setPerformanceFeeRecipient(
          address _performanceFeeRecipient
      ) external;
  
      function setProfitMaxUnlockTime(uint256 _profitMaxUnlockTime) external;
  
      function shutdownStrategy() external;
  
      function emergencyWithdraw(uint256 _amount) external;
  }
  
  /**
   * @title YearnV3 Base Strategy
   * @author yearn.finance
   * @notice
   *  BaseStrategy implements all of the required functionality to
   *  seamlessly integrate with the `TokenizedStrategy` implementation contract
   *  allowing anyone to easily build a fully permissionless ERC-4626 compliant
   *  Vault by inheriting this contract and overriding three simple functions.
  
   *  It utilizes an immutable proxy pattern that allows the BaseStrategy
   *  to remain simple and small. All standard logic is held within the
   *  `TokenizedStrategy` and is reused over any n strategies all using the
   *  `fallback` function to delegatecall the implementation so that strategists
   *  can only be concerned with writing their strategy specific code.
   *
   *  This contract should be inherited and the three main abstract methods
   *  `_deployFunds`, `_freeFunds` and `_harvestAndReport` implemented to adapt
   *  the Strategy to the particular needs it has to generate yield. There are
   *  other optional methods that can be implemented to further customize
   *  the strategy if desired.
   *
   *  All default storage for the strategy is controlled and updated by the
   *  `TokenizedStrategy`. The implementation holds a storage struct that
   *  contains all needed global variables in a manual storage slot. This
   *  means strategists can feel free to implement their own custom storage
   *  variables as they need with no concern of collisions. All global variables
   *  can be viewed within the Strategy by a simple call using the
   *  `TokenizedStrategy` variable. IE: TokenizedStrategy.globalVariable();.
   */
  abstract contract BaseStrategy {
      /*//////////////////////////////////////////////////////////////
                              MODIFIERS
      //////////////////////////////////////////////////////////////*/
      /**
       * @dev Used on TokenizedStrategy callback functions to make sure it is post
       * a delegateCall from this address to the TokenizedStrategy.
       */
      modifier onlySelf() {
          _onlySelf();
          _;
      }
  
      /**
       * @dev Use to assure that the call is coming from the strategies management.
       */
      modifier onlyManagement() {
          TokenizedStrategy.requireManagement(msg.sender);
          _;
      }
  
      /**
       * @dev Use to assure that the call is coming from either the strategies
       * management or the keeper.
       */
      modifier onlyKeepers() {
          TokenizedStrategy.requireKeeperOrManagement(msg.sender);
          _;
      }
  
      /**
       * @dev Use to assure that the call is coming from either the strategies
       * management or the emergency admin.
       */
      modifier onlyEmergencyAuthorized() {
          TokenizedStrategy.requireEmergencyAuthorized(msg.sender);
          _;
      }
  
      /**
       * @dev Require that the msg.sender is this address.
       */
      function _onlySelf() internal view {
          require(msg.sender == address(this), "!self");
      }
  
      /*//////////////////////////////////////////////////////////////
                              CONSTANTS
      //////////////////////////////////////////////////////////////*/
  
      /**
       * @dev This is the address of the TokenizedStrategy implementation
       * contract that will be used by all strategies to handle the
       * accounting, logic, storage etc.
       *
       * Any external calls to the that don't hit one of the functions
       * defined in this base or the strategy will end up being forwarded
       * through the fallback function, which will delegateCall this address.
       *
       * This address should be the same for every strategy, never be adjusted
       * and always be checked before any integration with the Strategy.
       */
      address public constant tokenizedStrategyAddress =
          0xBB51273D6c746910C7C06fe718f30c936170feD0;
  
      /*//////////////////////////////////////////////////////////////
                              IMMUTABLES
      //////////////////////////////////////////////////////////////*/
  
      /**
       * @dev Underlying asset the Strategy is earning yield on.
       * Stored here for cheap retrievals within the strategy.
       */
      ERC20 internal immutable asset;
  
      /**
       * @dev This variable is set to address(this) during initialization of each strategy.
       *
       * This can be used to retrieve storage data within the strategy
       * contract as if it were a linked library.
       *
       *       i.e. uint256 totalAssets = TokenizedStrategy.totalAssets()
       *
       * Using address(this) will mean any calls using this variable will lead
       * to a call to itself. Which will hit the fallback function and
       * delegateCall that to the actual TokenizedStrategy.
       */
      ITokenizedStrategy internal immutable TokenizedStrategy;
  
      /**
       * @notice Used to initialize the strategy on deployment.
       *
       * This will set the `TokenizedStrategy` variable for easy
       * internal view calls to the implementation. As well as
       * initializing the default storage variables based on the
       * parameters and using the deployer for the permissioned roles.
       *
       * @param _asset Address of the underlying asset.
       * @param _name Name the strategy will use.
       */
      constructor(address _asset, string memory _name) {
          asset = ERC20(_asset);
  
          // Set instance of the implementation for internal use.
          TokenizedStrategy = ITokenizedStrategy(address(this));
  
          // Initialize the strategy's storage variables.
          _delegateCall(
              abi.encodeCall(
                  ITokenizedStrategy.initialize,
                  (_asset, _name, msg.sender, msg.sender, msg.sender)
              )
          );
  
          // Store the tokenizedStrategyAddress at the standard implementation
          // address storage slot so etherscan picks up the interface. This gets
          // stored on initialization and never updated.
          assembly {
              sstore(
                  // keccak256('eip1967.proxy.implementation' - 1)
                  0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc,
                  tokenizedStrategyAddress
              )
          }
      }
  
      /*//////////////////////////////////////////////////////////////
                  NEEDED TO BE OVERRIDDEN BY STRATEGIST
      //////////////////////////////////////////////////////////////*/
  
      /**
       * @dev Can deploy up to '_amount' of 'asset' in the yield source.
       *
       * This function is called at the end of a {deposit} or {mint}
       * call. Meaning that unless a whitelist is implemented it will
       * be entirely permissionless and thus can be sandwiched or otherwise
       * manipulated.
       *
       * @param _amount The amount of 'asset' that the strategy can attempt
       * to deposit in the yield source.
       */
      function _deployFunds(uint256 _amount) internal virtual;
  
      /**
       * @dev Should attempt to free the '_amount' of 'asset'.
       *
       * NOTE: The amount of 'asset' that is already loose has already
       * been accounted for.
       *
       * This function is called during {withdraw} and {redeem} calls.
       * Meaning that unless a whitelist is implemented it will be
       * entirely permissionless and thus can be sandwiched or otherwise
       * manipulated.
       *
       * Should not rely on asset.balanceOf(address(this)) calls other than
       * for diff accounting purposes.
       *
       * Any difference between `_amount` and what is actually freed will be
       * counted as a loss and passed on to the withdrawer. This means
       * care should be taken in times of illiquidity. It may be better to revert
       * if withdraws are simply illiquid so not to realize incorrect losses.
       *
       * @param _amount, The amount of 'asset' to be freed.
       */
      function _freeFunds(uint256 _amount) internal virtual;
  
      /**
       * @dev Internal function to harvest all rewards, redeploy any idle
       * funds and return an accurate accounting of all funds currently
       * held by the Strategy.
       *
       * This should do any needed harvesting, rewards selling, accrual,
       * redepositing etc. to get the most accurate view of current assets.
       *
       * NOTE: All applicable assets including loose assets should be
       * accounted for in this function.
       *
       * Care should be taken when relying on oracles or swap values rather
       * than actual amounts as all Strategy profit/loss accounting will
       * be done based on this returned value.
       *
       * This can still be called post a shutdown, a strategist can check
       * `TokenizedStrategy.isShutdown()` to decide if funds should be
       * redeployed or simply realize any profits/losses.
       *
       * @return _totalAssets A trusted and accurate account for the total
       * amount of 'asset' the strategy currently holds including idle funds.
       */
      function _harvestAndReport()
          internal
          virtual
          returns (uint256 _totalAssets);
  
      /*//////////////////////////////////////////////////////////////
                      OPTIONAL TO OVERRIDE BY STRATEGIST
      //////////////////////////////////////////////////////////////*/
  
      /**
       * @dev Optional function for strategist to override that can
       *  be called in between reports.
       *
       * If '_tend' is used tendTrigger() will also need to be overridden.
       *
       * This call can only be called by a permissioned role so may be
       * through protected relays.
       *
       * This can be used to harvest and compound rewards, deposit idle funds,
       * perform needed position maintenance or anything else that doesn't need
       * a full report for.
       *
       *   EX: A strategy that can not deposit funds without getting
       *       sandwiched can use the tend when a certain threshold
       *       of idle to totalAssets has been reached.
       *
       * This will have no effect on PPS of the strategy till report() is called.
       *
       * @param _totalIdle The current amount of idle funds that are available to deploy.
       */
      function _tend(uint256 _totalIdle) internal virtual {}
  
      /**
       * @dev Optional trigger to override if tend() will be used by the strategy.
       * This must be implemented if the strategy hopes to invoke _tend().
       *
       * @return . Should return true if tend() should be called by keeper or false if not.
       */
      function _tendTrigger() internal view virtual returns (bool) {
          return false;
      }
  
      /**
       * @notice Returns if tend() should be called by a keeper.
       *
       * @return . Should return true if tend() should be called by keeper or false if not.
       * @return . Calldata for the tend call.
       */
      function tendTrigger() external view virtual returns (bool, bytes memory) {
          return (
              // Return the status of the tend trigger.
              _tendTrigger(),
              // And the needed calldata either way.
              abi.encodeWithSelector(ITokenizedStrategy.tend.selector)
          );
      }
  
      /**
       * @notice Gets the max amount of `asset` that an address can deposit.
       * @dev Defaults to an unlimited amount for any address. But can
       * be overridden by strategists.
       *
       * This function will be called before any deposit or mints to enforce
       * any limits desired by the strategist. This can be used for either a
       * traditional deposit limit or for implementing a whitelist etc.
       *
       *   EX:
       *      if(isAllowed[_owner]) return super.availableDepositLimit(_owner);
       *
       * This does not need to take into account any conversion rates
       * from shares to assets. But should know that any non max uint256
       * amounts may be converted to shares. So it is recommended to keep
       * custom amounts low enough as not to cause overflow when multiplied
       * by `totalSupply`.
       *
       * @param . The address that is depositing into the strategy.
       * @return . The available amount the `_owner` can deposit in terms of `asset`
       */
      function availableDepositLimit(
          address /*_owner*/
      ) public view virtual returns (uint256) {
          return type(uint256).max;
      }
  
      /**
       * @notice Gets the max amount of `asset` that can be withdrawn.
       * @dev Defaults to an unlimited amount for any address. But can
       * be overridden by strategists.
       *
       * This function will be called before any withdraw or redeem to enforce
       * any limits desired by the strategist. This can be used for illiquid
       * or sandwichable strategies. It should never be lower than `totalIdle`.
       *
       *   EX:
       *       return TokenIzedStrategy.totalIdle();
       *
       * This does not need to take into account the `_owner`'s share balance
       * or conversion rates from shares to assets.
       *
       * @param . The address that is withdrawing from the strategy.
       * @return . The available amount that can be withdrawn in terms of `asset`
       */
      function availableWithdrawLimit(
          address /*_owner*/
      ) public view virtual returns (uint256) {
          return type(uint256).max;
      }
  
      /**
       * @dev Optional function for a strategist to override that will
       * allow management to manually withdraw deployed funds from the
       * yield source if a strategy is shutdown.
       *
       * This should attempt to free `_amount`, noting that `_amount` may
       * be more than is currently deployed.
       *
       * NOTE: This will not realize any profits or losses. A separate
       * {report} will be needed in order to record any profit/loss. If
       * a report may need to be called after a shutdown it is important
       * to check if the strategy is shutdown during {_harvestAndReport}
       * so that it does not simply re-deploy all funds that had been freed.
       *
       * EX:
       *   if(freeAsset > 0 && !TokenizedStrategy.isShutdown()) {
       *       depositFunds...
       *    }
       *
       * @param _amount The amount of asset to attempt to free.
       */
      function _emergencyWithdraw(uint256 _amount) internal virtual {}
  
      /*//////////////////////////////////////////////////////////////
                          TokenizedStrategy HOOKS
      //////////////////////////////////////////////////////////////*/
  
      /**
       * @notice Can deploy up to '_amount' of 'asset' in yield source.
       * @dev Callback for the TokenizedStrategy to call during a {deposit}
       * or {mint} to tell the strategy it can deploy funds.
       *
       * Since this can only be called after a {deposit} or {mint}
       * delegateCall to the TokenizedStrategy msg.sender == address(this).
       *
       * Unless a whitelist is implemented this will be entirely permissionless
       * and thus can be sandwiched or otherwise manipulated.
       *
       * @param _amount The amount of 'asset' that the strategy can
       * attempt to deposit in the yield source.
       */
      function deployFunds(uint256 _amount) external virtual onlySelf {
          _deployFunds(_amount);
      }
  
      /**
       * @notice Should attempt to free the '_amount' of 'asset'.
       * @dev Callback for the TokenizedStrategy to call during a withdraw
       * or redeem to free the needed funds to service the withdraw.
       *
       * This can only be called after a 'withdraw' or 'redeem' delegateCall
       * to the TokenizedStrategy so msg.sender == address(this).
       *
       * @param _amount The amount of 'asset' that the strategy should attempt to free up.
       */
      function freeFunds(uint256 _amount) external virtual onlySelf {
          _freeFunds(_amount);
      }
  
      /**
       * @notice Returns the accurate amount of all funds currently
       * held by the Strategy.
       * @dev Callback for the TokenizedStrategy to call during a report to
       * get an accurate accounting of assets the strategy controls.
       *
       * This can only be called after a report() delegateCall to the
       * TokenizedStrategy so msg.sender == address(this).
       *
       * @return . A trusted and accurate account for the total amount
       * of 'asset' the strategy currently holds including idle funds.
       */
      function harvestAndReport() external virtual onlySelf returns (uint256) {
          return _harvestAndReport();
      }
  
      /**
       * @notice Will call the internal '_tend' when a keeper tends the strategy.
       * @dev Callback for the TokenizedStrategy to initiate a _tend call in the strategy.
       *
       * This can only be called after a tend() delegateCall to the TokenizedStrategy
       * so msg.sender == address(this).
       *
       * We name the function `tendThis` so that `tend` calls are forwarded to
       * the TokenizedStrategy.
  
       * @param _totalIdle The amount of current idle funds that can be
       * deployed during the tend
       */
      function tendThis(uint256 _totalIdle) external virtual onlySelf {
          _tend(_totalIdle);
      }
  
      /**
       * @notice Will call the internal '_emergencyWithdraw' function.
       * @dev Callback for the TokenizedStrategy during an emergency withdraw.
       *
       * This can only be called after a emergencyWithdraw() delegateCall to
       * the TokenizedStrategy so msg.sender == address(this).
       *
       * We name the function `shutdownWithdraw` so that `emergencyWithdraw`
       * calls are forwarded to the TokenizedStrategy.
       *
       * @param _amount The amount of asset to attempt to free.
       */
      function shutdownWithdraw(uint256 _amount) external virtual onlySelf {
          _emergencyWithdraw(_amount);
      }
  
      /**
       * @dev Function used to delegate call the TokenizedStrategy with
       * certain `_calldata` and return any return values.
       *
       * This is used to setup the initial storage of the strategy, and
       * can be used by strategist to forward any other call to the
       * TokenizedStrategy implementation.
       *
       * @param _calldata The abi encoded calldata to use in delegatecall.
       * @return . The return value if the call was successful in bytes.
       */
      function _delegateCall(
          bytes memory _calldata
      ) internal returns (bytes memory) {
          // Delegate call the tokenized strategy with provided calldata.
          (bool success, bytes memory result) = tokenizedStrategyAddress
              .delegatecall(_calldata);
  
          // If the call reverted. Return the error.
          if (!success) {
              assembly {
                  let ptr := mload(0x40)
                  let size := returndatasize()
                  returndatacopy(ptr, 0, size)
                  revert(ptr, size)
              }
          }
  
          // Return the result.
          return result;
      }
  
      /**
       * @dev Execute a function on the TokenizedStrategy and return any value.
       *
       * This fallback function will be executed when any of the standard functions
       * defined in the TokenizedStrategy are called since they wont be defined in
       * this contract.
       *
       * It will delegatecall the TokenizedStrategy implementation with the exact
       * calldata and return any relevant values.
       *
       */
      fallback() external {
          // load our target address
          address _tokenizedStrategyAddress = tokenizedStrategyAddress;
          // Execute external function using delegatecall and return any value.
          assembly {
              // Copy function selector and any arguments.
              calldatacopy(0, 0, calldatasize())
              // Execute function delegatecall.
              let result := delegatecall(
                  gas(),
                  _tokenizedStrategyAddress,
                  0,
                  calldatasize(),
                  0,
                  0
              )
              // Get any return value
              returndatacopy(0, 0, returndatasize())
              // Return any return value or error back to the caller
              switch result
              case 0 {
                  revert(0, returndatasize())
              }
              default {
                  return(0, returndatasize())
              }
          }
      }
  }
  
  /**
   *   @title Base Health Check
   *   @author Yearn.finance
   *   @notice This contract can be inherited by any Yearn
   *   V3 strategy wishing to implement a health check during
   *   the `report` function in order to prevent any unexpected
   *   behavior from being permanently recorded as well as the
   *   `checkHealth` modifier.
   *
   *   A strategist simply needs to inherit this contract. Set
   *   the limit ratios to the desired amounts and then
   *   override `_harvestAndReport()` just as they otherwise
   *  would. If the profit or loss that would be recorded is
   *   outside the acceptable bounds the tx will revert.
   *
   *   The healthcheck does not prevent a strategy from reporting
   *   losses, but rather can make sure manual intervention is
   *   needed before reporting an unexpected loss or profit.
   */
  abstract contract BaseHealthCheck is BaseStrategy {
      // Can be used to determine if a healthcheck should be called.
      // Defaults to true;
      bool public doHealthCheck = true;
  
      uint256 internal constant MAX_BPS = 10_000;
  
      // Default profit limit to 100%.
      uint16 private _profitLimitRatio = uint16(MAX_BPS);
  
      // Defaults loss limit to 0.
      uint16 private _lossLimitRatio;
  
      constructor(
          address _asset,
          string memory _name
      ) BaseStrategy(_asset, _name) {}
  
      /**
       * @notice Returns the current profit limit ratio.
       * @dev Use a getter function to keep the variable private.
       * @return . The current profit limit ratio.
       */
      function profitLimitRatio() public view returns (uint256) {
          return _profitLimitRatio;
      }
  
      /**
       * @notice Returns the current loss limit ratio.
       * @dev Use a getter function to keep the variable private.
       * @return . The current loss limit ratio.
       */
      function lossLimitRatio() public view returns (uint256) {
          return _lossLimitRatio;
      }
  
      /**
       * @notice Set the `profitLimitRatio`.
       * @dev Denominated in basis points. I.E. 1_000 == 10%.
       * @param _newProfitLimitRatio The mew profit limit ratio.
       */
      function setProfitLimitRatio(
          uint256 _newProfitLimitRatio
      ) external onlyManagement {
          _setProfitLimitRatio(_newProfitLimitRatio);
      }
  
      /**
       * @dev Internally set the profit limit ratio. Denominated
       * in basis points. I.E. 1_000 == 10%.
       * @param _newProfitLimitRatio The mew profit limit ratio.
       */
      function _setProfitLimitRatio(uint256 _newProfitLimitRatio) internal {
          require(_newProfitLimitRatio > 0, "!zero profit");
          require(_newProfitLimitRatio <= type(uint16).max, "!too high");
          _profitLimitRatio = uint16(_newProfitLimitRatio);
      }
  
      /**
       * @notice Set the `lossLimitRatio`.
       * @dev Denominated in basis points. I.E. 1_000 == 10%.
       * @param _newLossLimitRatio The new loss limit ratio.
       */
      function setLossLimitRatio(
          uint256 _newLossLimitRatio
      ) external onlyManagement {
          _setLossLimitRatio(_newLossLimitRatio);
      }
  
      /**
       * @dev Internally set the loss limit ratio. Denominated
       * in basis points. I.E. 1_000 == 10%.
       * @param _newLossLimitRatio The new loss limit ratio.
       */
      function _setLossLimitRatio(uint256 _newLossLimitRatio) internal {
          require(_newLossLimitRatio < MAX_BPS, "!loss limit");
          _lossLimitRatio = uint16(_newLossLimitRatio);
      }
  
      /**
       * @notice Turns the healthcheck on and off.
       * @dev If turned off the next report will auto turn it back on.
       * @param _doHealthCheck Bool if healthCheck should be done.
       */
      function setDoHealthCheck(bool _doHealthCheck) public onlyManagement {
          doHealthCheck = _doHealthCheck;
      }
  
      /**
       * @notice OVerrides the default {harvestAndReport} to include a healthcheck.
       * @return _totalAssets New totalAssets post report.
       */
      function harvestAndReport()
          external
          override
          onlySelf
          returns (uint256 _totalAssets)
      {
          // Let the strategy report.
          _totalAssets = _harvestAndReport();
  
          // Run the healthcheck on the amount returned.
          _executeHealthCheck(_totalAssets);
      }
  
      /**
       * @dev To be called during a report to make sure the profit
       * or loss being recorded is within the acceptable bound.
       *
       * @param _newTotalAssets The amount that will be reported.
       */
      function _executeHealthCheck(uint256 _newTotalAssets) internal virtual {
          if (!doHealthCheck) {
              doHealthCheck = true;
              return;
          }
  
          // Get the current total assets from the implementation.
          uint256 currentTotalAssets = TokenizedStrategy.totalAssets();
  
          if (_newTotalAssets > currentTotalAssets) {
              require(
                  ((_newTotalAssets - currentTotalAssets) <=
                      (currentTotalAssets * uint256(_profitLimitRatio)) /
                          MAX_BPS),
                  "healthCheck"
              );
          } else if (currentTotalAssets > _newTotalAssets) {
              require(
                  (currentTotalAssets - _newTotalAssets <=
                      ((currentTotalAssets * uint256(_lossLimitRatio)) /
                          MAX_BPS)),
                  "healthCheck"
              );
          }
      }
  }
  
  // OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)
  
  // OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
  
  /**
   * @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
       *
       * Furthermore, `isContract` will also return true if the target contract within
       * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
       * which only has an effect at the end of a transaction.
       * ====
       *
       * [IMPORTANT]
       * ====
       * You shouldn't rely on `isContract` to protect against flash loan attacks!
       *
       * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
       * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
       * constructor.
       * ====
       */
      function isContract(address account) internal view returns (bool) {
          // This method relies on extcodesize/address.code.length, which returns 0
          // for contracts in construction, since the code is only stored at the end
          // of the constructor execution.
  
          return account.code.length > 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://consensys.net/diligence/blog/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/v0.8.0/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 functionCallWithValue(target, data, 0, "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");
          (bool success, bytes memory returndata) = target.call{value: value}(data);
          return verifyCallResultFromTarget(target, 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) {
          (bool success, bytes memory returndata) = target.staticcall(data);
          return verifyCallResultFromTarget(target, 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) {
          (bool success, bytes memory returndata) = target.delegatecall(data);
          return verifyCallResultFromTarget(target, success, returndata, errorMessage);
      }
  
      /**
       * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
       * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
       *
       * _Available since v4.8._
       */
      function verifyCallResultFromTarget(
          address target,
          bool success,
          bytes memory returndata,
          string memory errorMessage
      ) internal view returns (bytes memory) {
          if (success) {
              if (returndata.length == 0) {
                  // only check isContract if the call was successful and the return data is empty
                  // otherwise we already know that it was a contract
                  require(isContract(target), "Address: call to non-contract");
              }
              return returndata;
          } else {
              _revert(returndata, errorMessage);
          }
      }
  
      /**
       * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
       * revert reason or 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 {
              _revert(returndata, errorMessage);
          }
      }
  
      function _revert(bytes memory returndata, string memory errorMessage) private pure {
          // 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
              /// @solidity memory-safe-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;
  
      /**
       * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
       * non-reverting calls are assumed to be successful.
       */
      function safeTransfer(IERC20 token, address to, uint256 value) internal {
          _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
      }
  
      /**
       * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
       * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
       */
      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));
      }
  
      /**
       * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
       * non-reverting calls are assumed to be successful.
       */
      function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
          uint256 oldAllowance = token.allowance(address(this), spender);
          _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
      }
  
      /**
       * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
       * non-reverting calls are assumed to be successful.
       */
      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");
              _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
          }
      }
  
      /**
       * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
       * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
       * to be set to zero before setting it to a non-zero value, such as USDT.
       */
      function forceApprove(IERC20 token, address spender, uint256 value) internal {
          bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
  
          if (!_callOptionalReturnBool(token, approvalCall)) {
              _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
              _callOptionalReturn(token, approvalCall);
          }
      }
  
      /**
       * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
       * Revert on invalid signature.
       */
      function safePermit(
          IERC20Permit token,
          address owner,
          address spender,
          uint256 value,
          uint256 deadline,
          uint8 v,
          bytes32 r,
          bytes32 s
      ) internal {
          uint256 nonceBefore = token.nonces(owner);
          token.permit(owner, spender, value, deadline, v, r, s);
          uint256 nonceAfter = token.nonces(owner);
          require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
      }
  
      /**
       * @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");
          require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
      }
  
      /**
       * @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).
       *
       * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
       */
      function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
          // 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 cannot use {Address-functionCall} here since this should return false
          // and not revert is the subcall reverts.
  
          (bool success, bytes memory returndata) = address(token).call(data);
          return
              success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
      }
  }
  
  interface IPendleMarket {
      function readTokens()
          external
          view
          returns (address _SY, address _PT, address _YT);
      function isExpired() external view returns (bool);
  }
  
  interface ISY {
      function deposit(
          address receiver,
          address tokenIn,
          uint256 amountTokenToDeposit,
          uint256 minSharesOut
      ) external payable returns (uint256 amountSharesOut);
      function redeem(
          address receiver,
          uint256 amountSharesToRedeem,
          address tokenOut,
          uint256 minTokenOut,
          bool burnFromInternalBalance
      ) external payable returns (uint256 amountTokenOut);
      function isValidTokenIn(address) external view returns (bool);
      function isValidTokenOut(address) external view returns (bool);
      function previewRedeem(
          address tokenOut,
          uint256 amountSharesToRedeem
      ) external view returns (uint256 amountTokenOut);
  }
  
  interface IPendleRouter {
      struct ApproxParams {
          uint256 guessMin;
          uint256 guessMax;
          uint256 guessOffchain; // pass 0 in to skip this variable
          uint256 maxIteration; // every iteration, the diff between guessMin and guessMax will be divided by 2
          uint256 eps; // the max eps between the returned result & the correct result, base 1e18. Normally this number will be set
          // to 1e15 (1e18/1000 = 0.1%)
      }
  
      struct LimitOrderData {
          address limitRouter;
          uint256 epsSkipMarket; // only used for swap operations, will be ignored otherwise
          FillOrderParams[] normalFills;
          FillOrderParams[] flashFills;
          bytes optData;
      }
  
      struct FillOrderParams {
          Order order;
          bytes signature;
          uint256 makingAmount;
      }
  
      struct Order {
          uint256 salt;
          uint256 expiry;
          uint256 nonce;
          OrderType orderType;
          address token;
          address YT;
          address maker;
          address receiver;
          uint256 makingAmount;
          uint256 lnImpliedRate;
          uint256 failSafeRate;
          bytes permit;
      }
  
      enum OrderType {
          SY_FOR_PT,
          PT_FOR_SY,
          SY_FOR_YT,
          YT_FOR_SY
      }
  
      function swapExactSyForPt(
          address receiver,
          address market,
          uint256 exactSyIn,
          uint256 minPtOut,
          ApproxParams calldata guessPtOut,
          LimitOrderData calldata limit
      ) external returns (uint256 netPtOut, uint256 netSyFee);
  
      function swapExactPtForSy(
          address receiver,
          address market,
          uint256 exactPtIn,
          uint256 minSyOut,
          LimitOrderData calldata limit
      ) external returns (uint256 netSyOut, uint256 netSyFee);
  
      function redeemPyToSy(
          address receiver,
          address YT,
          uint256 netPyIn,
          uint256 minSyOut
      ) external returns (uint256 netSyOut);
  }
  
  interface IPendleOracle {
      function getPtToSyRate(
          address market,
          uint32 oracleDuration
      ) external view returns (uint256 rate);
      function getOracleState(
          address market,
          uint32 oracleDuration
      )
          external
          view
          returns (
              bool increaseCardinalityRequired,
              uint16 cardinalityRequired,
              bool oldestObservationSatisfied
          );
  }
  
  /// @title yearn-v3-SingleSidedPTcore
  /// @author mil0x
  /// @notice yearn-v3 Strategy that invests into Pendle PT positions.
  contract SingleSidedPTcore is BaseHealthCheck {
      using SafeERC20 for ERC20;
  
      ///@notice Address of our Pendle market.
      address public market;
      address internal immutable oracle;
  
      ///@notice Oracle TWAP duration, in seconds.
      uint32 public oracleDuration;
  
      ///@notice Bool if the strategy is open for any depositors. Default = true.
      bool public open = true;
  
      ///@notice Mapping of addresses allowed to deposit.
      mapping(address => bool) public allowed;
  
      struct TradeParams {
          ///@notice Set the minimum asset amount to be converted to PT. Set to max to prevent PT buying.
          uint128 minAssetAmountToPT;
          ///@notice The max in asset will be invested by the keeper at a time.
          uint128 maxSingleTrade;
      }
  
      ///@notice Parameters used to contrin size of strategy investing into PT.
      TradeParams public tradeParams;
  
      ///@notice The total deposit limit for the strategy. Use in case we want to cap a given strategy.
      uint256 public depositLimit = type(uint256).max;
  
      address internal constant pendleRouter =
          0x888888888889758F76e7103c6CbF23ABbF58F946;
  
      ///@notice Parameters passed to Pendle's router for swaps in using binary search.
      IPendleRouter.ApproxParams public routerParams;
  
      ///@notice Address of this market's SY token.
      address public immutable SY;
  
      ///@notice Address of this market's PT token.
      address public PT;
      address internal YT;
  
      ///@notice Amount in Basis Points to allow for slippage when reporting.
      uint256 public swapSlippageBPS;
  
      ///@notice Amount in Basis Points to account for as buffer when reporting. Can also manually account for bigger depeg scenarios.
      uint256 public bufferSlippageBPS;
  
      // Struct for all variables involved in tendTrigger
      struct TendTriggerParams {
          ///@notice The amount in asset that will trigger a tend if idle.
          uint128 depositTrigger;
          ///@notice The max amount the base fee can be for a tend to happen.
          uint48 maxTendBaseFee;
          ///@notice Minimum time between deposits to wait.
          uint40 minDepositInterval;
          ///@notice Time stamp of the last deployment of funds.
          uint40 lastDeposit;
      }
  
      ///@notice Contains adjustable variables that govern when to tend this strategy.
      TendTriggerParams public tendTriggerParams;
  
      ///@notice Yearn governance
      address public immutable GOV;
  
      uint256 internal constant WAD = 1e18;
  
      constructor(
          address _asset,
          address _market,
          address _oracle,
          address _GOV,
          string memory _name
      ) BaseHealthCheck(_asset, _name) {
          market = _market;
          require(!_isExpired(), "expired");
          oracle = _oracle;
          //Default oracle duration to 1 hour price smoothing recommendation by Pendle Finance
          oracleDuration = 3600;
  
          //Default maxSingleTrade to 15 ETH as a majority of markets are ETH based. Change this for non-ETH.
          tradeParams.maxSingleTrade = 15e18;
  
          (SY, PT, YT) = IPendleMarket(_market).readTokens();
          require(ISY(SY).isValidTokenOut(_asset), "!valid out");
          require(ISY(SY).isValidTokenIn(_asset), "!valid in");
  
          // Default slippage to 0.5%.
          swapSlippageBPS = 50;
          bufferSlippageBPS = 50;
  
          routerParams.guessMax = type(uint256).max;
          routerParams.maxIteration = 256;
          routerParams.eps = 1e15; // max 0.1% unused
  
          TendTriggerParams memory _tendTriggerParams;
          _tendTriggerParams.depositTrigger = 5e18; // The amount in asset that will trigger a tend if idle. Default to 5 ETH; update for non-ETH.
          _tendTriggerParams.maxTendBaseFee = 20e9; // The max amount the base fee can be for a tend to happen. Default max tend fee to 20 gwei.
          _tendTriggerParams.minDepositInterval = 43200; // Minimum time between deposits to wait. Default min deposit interval to 12 hours.
          tendTriggerParams = _tendTriggerParams;
  
          // Allow a 500% gain.
          _setProfitLimitRatio(500_00);
  
          GOV = _GOV;
  
          //approvals:
          ERC20(_asset).forceApprove(SY, type(uint256).max);
          ERC20(SY).forceApprove(pendleRouter, type(uint256).max);
          ERC20(PT).forceApprove(pendleRouter, type(uint256).max);
      }
  
      /*//////////////////////////////////////////////////////////////
                  INTERNAL
      //////////////////////////////////////////////////////////////*/
  
      function _deployFunds(uint256 _amount) internal override {
          //do nothing, we want to only have the keeper swap funds
      }
  
      function _invest(uint256 _amount) internal {
          //asset --> SY
          ISY(SY).deposit(address(this), address(asset), _amount, 0);
          _amount = ERC20(SY).balanceOf(address(this));
  
          //SY --> PT
          IPendleRouter.LimitOrderData memory limit; //skip limit order by passing zero address
          uint256 minPTout = (_SYtoPT(_amount) * (MAX_BPS - swapSlippageBPS)) /
              MAX_BPS; //calculate minimum expected PT out
          IPendleRouter(pendleRouter).swapExactSyForPt(
              address(this),
              market,
              _amount,
              minPTout,
              routerParams,
              limit
          );
  
          // Update the last time that we deposited.
          tendTriggerParams.lastDeposit = uint40(block.timestamp);
      }
  
      function _freeFunds(uint256 _amount) internal override {
          //Redeem PT shares proportional to the SSPT shares redeemed:
          uint256 totalAssets = TokenizedStrategy.totalAssets();
          uint256 totalDebt = totalAssets - _balanceOfAsset();
          uint256 PTtoUninvest = (_balanceOfPT() * _amount) / totalDebt;
          _uninvest(PTtoUninvest);
      }
  
      function _uninvest(uint256 currentBalance) internal returns (uint256) {
          if (currentBalance == 0) return 0;
          //PT --> SY
          if (_isExpired()) {
              //if expired, redeem PY to SY
              currentBalance = IPendleRouter(pendleRouter).redeemPyToSy(
                  address(this),
                  YT,
                  currentBalance,
                  0
              );
          } else {
              IPendleRouter.LimitOrderData memory limit; //skip limit order by passing zero address
              // We don't enforce any min amount out since withdrawer's can use 'maxLoss'
              (currentBalance, ) = IPendleRouter(pendleRouter).swapExactPtForSy(
                  address(this),
                  market,
                  currentBalance,
                  0,
                  limit
              );
              if (currentBalance == 0) return 0;
          }
          //SY --> asset
          // We don't enforce any min amount out since withdrawers can use 'maxLoss'
          return
              ISY(SY).redeem(
                  address(this),
                  currentBalance,
                  address(asset),
                  0,
                  false
              );
      }
  
      function _harvestAndReport()
          internal
          override
          returns (uint256 _totalAssets)
      {
          if (!_isExpired() && !TokenizedStrategy.isShutdown()) {
              uint256 assetBalance = _balanceOfAsset();
              TradeParams memory _tradeParams = tradeParams;
              if (assetBalance > _tradeParams.minAssetAmountToPT) {
                  _invest(_min(assetBalance, _tradeParams.maxSingleTrade));
              }
          }
  
          _totalAssets =
              _balanceOfAsset() +
              (_PTtoAsset(_balanceOfPT()) * (MAX_BPS - bufferSlippageBPS)) /
              MAX_BPS; //reduce PT balance by bufferSlippageBPS to account for the fact that it will need to be swapped back to asset
      }
  
      function _SYtoPT(uint256 _amount) internal view returns (uint256) {
          return
              (_amount * WAD) /
              IPendleOracle(oracle).getPtToSyRate(market, oracleDuration);
      }
  
      function _PTtoSY(uint256 _amount) internal view returns (uint256) {
          return
              (_amount *
                  IPendleOracle(oracle).getPtToSyRate(market, oracleDuration)) /
              WAD;
      }
  
      function _PTtoAsset(uint256 _amount) internal view returns (uint256) {
          return ISY(SY).previewRedeem(address(asset), _PTtoSY(_amount));
      }
  
      function _tend(uint256) internal override {
          _invest(_min(_balanceOfAsset(), tradeParams.maxSingleTrade));
      }
  
      function _tendTrigger() internal view override returns (bool _shouldTend) {
          TendTriggerParams memory _tendTriggerParams = tendTriggerParams;
          if (
              !_isExpired() &&
              block.timestamp - _tendTriggerParams.lastDeposit >
              _tendTriggerParams.minDepositInterval &&
              _balanceOfAsset() > _tendTriggerParams.depositTrigger &&
              tradeParams.maxSingleTrade > 0 &&
              !TokenizedStrategy.isShutdown()
          ) {
              _shouldTend = block.basefee < _tendTriggerParams.maxTendBaseFee;
          }
      }
  
      function availableDepositLimit(
          address _owner
      ) public view override returns (uint256) {
          // If the owner is whitelisted or the strategy is open.
          if (allowed[_owner] || open) {
              uint256 totalDeposits = TokenizedStrategy.totalAssets();
              if (depositLimit > totalDeposits) {
                  return depositLimit - totalDeposits;
              } else {
                  return 0;
              }
          } else {
              return 0;
          }
      }
  
      function _balanceOfAsset() internal view returns (uint256) {
          return asset.balanceOf(address(this));
      }
  
      function _balanceOfPT() internal view returns (uint256) {
          return ERC20(PT).balanceOf(address(this));
      }
  
      function _isExpired() internal view returns (bool) {
          return IPendleMarket(market).isExpired();
      }
  
      function _checkOracle(
          address _market,
          uint32 _oracleDuration
      ) internal view {
          (
              bool increaseCardinalityRequired,
              ,
              bool oldestObservationSatisfied
          ) = IPendleOracle(oracle).getOracleState(_market, _oracleDuration);
          if (increaseCardinalityRequired || !oldestObservationSatisfied) {
              revert("oracle not ready");
          }
      }
  
      function _min(uint256 a, uint256 b) internal pure returns (uint256) {
          return a < b ? a : b;
      }
  
      /*//////////////////////////////////////////////////////////////
                  EXTERNAL:
      //////////////////////////////////////////////////////////////*/
  
      function balanceOfAsset() external view returns (uint256) {
          return _balanceOfAsset();
      }
  
      function balanceOfPT() external view returns (uint256) {
          return _balanceOfPT();
      }
  
      function isExpired() external view returns (bool) {
          return _isExpired();
      }
  
      /**
       * @notice Set oracle duration price smoothing
       * @param _oracleDuration twap duration in seconds
       */
      function setOracleDuration(
          uint32 _oracleDuration
      ) external onlyEmergencyAuthorized {
          require(_oracleDuration >= 900, "duration too low");
          _checkOracle(market, _oracleDuration);
          oracleDuration = _oracleDuration;
      }
  
      /**
       * @notice Set the tradeParams for the strategy to decide on minimum investment and maximum single investments for the keeper.
       * @param _minAssetAmountToPT Set the minimum amount in asset that should be converted to PT. Set this to max in order to not trigger any PT buying.
       * @param _maxSingleTrade Set the max in asset amount that will be invested by the keeper at a time. Can also be used to pause keeper investments.
       */
      function setTradeParams(
          uint128 _minAssetAmountToPT,
          uint128 _maxSingleTrade
      ) external onlyManagement {
          require(
              _maxSingleTrade <= type(uint128).max &&
                  _minAssetAmountToPT <= type(uint128).max,
              "too large"
          );
          require(_maxSingleTrade >= _minAssetAmountToPT, "wrong order");
          require(tendTriggerParams.depositTrigger >= _minAssetAmountToPT, "minAsset too large");
          TradeParams memory _tradeParams;
          _tradeParams.minAssetAmountToPT = _minAssetAmountToPT;
          _tradeParams.maxSingleTrade = _maxSingleTrade;
          tradeParams = _tradeParams;
      }
  
      /**
       * @notice Set the routerParams for the pendleRouter. Pendle's AMM only supports the built-in swapSyForExactPt. To execute a swapExactSyForPt, the
       *  router will conduct a binary search to determine the amount of PT to swap.
       * @param _guessMin The minimum value for binary search. Default: 0.
       * @param _guessMax The maximum value for binary search. Default: type(uint256).max.
       * @param _maxIteration The maximum number of times binary search will be performed. Default: 256.
       * @param _eps The precision of binary search - the maximum proportion of the input that can be unused. Default: 1e15 == max 0.1% unused.
       *  Alternatively: 1e14 implies that no more than 0.01% unused.
       */
      function setRouterParams(
          uint256 _guessMin,
          uint256 _guessMax,
          uint256 _maxIteration,
          uint256 _eps
      ) external onlyManagement {
          routerParams.guessMin = _guessMin; // default: 0
          routerParams.guessMax = _guessMax; // default: type(uint256).max
          routerParams.maxIteration = _maxIteration; // default: 256
          routerParams.eps = _eps; // default: 1e15 == max 0.1% unused. Alternatively: 1e14 implies that no more than 0.01% unused.
      }
  
      /**
       * @notice Set the tendTriggerParams for all variables involved in tendTrigger.
       * @param _depositTrigger The amount in asset that will trigger a tend if idle.
       * @param _maxTendBaseFee The max amount the base fee can be for a tend to happen in wei.
       * @param _minDepositInterval Minimum time between deposits to wait in seconds.
       */
      function setTendTriggerParams(
          uint128 _depositTrigger,
          uint48 _maxTendBaseFee,
          uint40 _minDepositInterval
      ) external onlyManagement {
          require(_minDepositInterval > 0, "interval too low");
          require(_depositTrigger <= type(uint128).max, "too large");
          require(_depositTrigger >= tradeParams.minAssetAmountToPT, "trigger too small");
          tendTriggerParams.depositTrigger = _depositTrigger;
          tendTriggerParams.maxTendBaseFee = _maxTendBaseFee;
          tendTriggerParams.minDepositInterval = _minDepositInterval;
      }
  
      /**
       * @notice Set the deposit limit in asset amount. Set this to 0 to disallow deposits.
       * @param _depositLimit the deposit limit in asset units
       */
      function setDepositLimit(uint256 _depositLimit) external onlyManagement {
          depositLimit = _depositLimit;
      }
  
      /**
       * @notice Set the slippage for keeper investments in basis points.
       * @param _swapSlippageBPS the maximum slippage in basis points (BPS)
       */
      function setSwapSlippageBPS(
          uint256 _swapSlippageBPS
      ) external onlyManagement {
          require(_swapSlippageBPS <= MAX_BPS);
          swapSlippageBPS = _swapSlippageBPS;
      }
  
      /**
       * @notice Set the buffer for reports in basis points. Can also be used to manually account for bigger depeg scenarios
       * @param _bufferSlippageBPS the buffer slippage in basis points (BPS)
       */
      function setBufferSlippageBPS(
          uint256 _bufferSlippageBPS
      ) external onlyManagement {
          require(_bufferSlippageBPS <= MAX_BPS);
          bufferSlippageBPS = _bufferSlippageBPS;
      }
  
      /**
       * @notice Change if anyone can deposit in or only white listed addresses
       * @param _open the bool deciding if anyone can deposit (true) or only whitelisted addresses (false)
       */
      function setOpen(bool _open) external onlyManagement {
          open = _open;
      }
  
      /**
       * @notice Set or update an addresses whitelist status.
       * @param _address the address for which to change the whitelist status
       * @param _allowed the bool to set as whitelisted (true) or not (false)
       */
      function setAllowed(
          address _address,
          bool _allowed
      ) external onlyManagement {
          allowed[_address] = _allowed;
      }
  
      /*//////////////////////////////////////////////////////////////
                  EMERGENCY & GOVERNANCE:
      //////////////////////////////////////////////////////////////*/
  
      /**
       * @notice Manually pull funds out from the PT stack without shuting down. This will also stop keeper investments.
       * @param _amount the PT amount to uninvest into asset
       * @param _expectedAssetAmountOut the minimum acceptable asset amount as a result of uninvestment
       */
      function manualWithdraw(
          uint256 _amount,
          uint256 _expectedAssetAmountOut
      ) external onlyEmergencyAuthorized {
          tradeParams.maxSingleTrade = 0;
          uint256 currentBalance = _balanceOfPT();
          if (_amount > currentBalance) {
              _amount = currentBalance;
          }
          uint256 _amountOut = _uninvest(_amount);
          require(_amountOut >= _expectedAssetAmountOut, "too little amountOut");
      }
  
      /**
       * @notice Manually pull funds out from the PT stack after the strategy has been shutdown.
       * @param _amount the PT amount to uninvest into asset
       */
      function _emergencyWithdraw(uint256 _amount) internal override {
          uint256 currentBalance = _balanceOfPT();
          if (_amount > currentBalance) {
              _amount = currentBalance;
          }
          uint256 expectedAssetAmountOut = _PTtoAsset(_amount);
          uint256 _amountOut = _uninvest(_amount);
          require(
              _amountOut >=
                  (expectedAssetAmountOut * (MAX_BPS - swapSlippageBPS)) /
                      MAX_BPS,
              "too little amountOut"
          );
      }
  
      /**
       * @notice Redeem all PT into asset and rollover the market into a new maturity. Only callable by governance.
       * @param _market the market address (not PT address) for the new maturity to rollover into
       * @param _minAssetAmountOut the acceptable minimum amount of asset out for the PT amount currently held by the strategy
       */
      function rolloverMaturity(
          address _market,
          uint256 _minAssetAmountOut
      ) external onlyGovernance {
          require(_isExpired(), "not expired");
          require(_market != address(0), "!market");
          require(market != _market, "same market");
  
          //check new market exists long enough for preset oracleDuration
          _checkOracle(_market, oracleDuration);
  
          //redeem all PT to SY
          uint256 currentBalance = _balanceOfPT();
          if (currentBalance > 0) {
              currentBalance = IPendleRouter(pendleRouter).redeemPyToSy(
                  address(this),
                  YT,
                  currentBalance,
                  0
              );
          }
  
          //set addresses to new maturity
          market = _market;
          require(!_isExpired(), "expired");
          (address _SY, address _PT, address _YT) = IPendleMarket(_market)
              .readTokens();
          require(_SY == SY, "wrong SY");
          PT = _PT;
          YT = _YT;
          ERC20(_PT).forceApprove(pendleRouter, type(uint256).max);
  
          //redeem all SY into asset (let keeper move asset to new PT over time)
          if (currentBalance == 0 && _minAssetAmountOut == 0) return;
          ISY(SY).redeem(
              address(this),
              currentBalance,
              address(asset),
              _minAssetAmountOut,
              false
          );
      }
  
      /**
       * @notice Sweep of non-asset ERC20 tokens to governance (onlyGovernance)
       * @param _token The ERC20 token to sweep
       */
      function sweep(address _token) external onlyGovernance {
          require(_token != address(asset), "!asset");
          require(_token != PT, "!PT");
          ERC20(_token).safeTransfer(GOV, ERC20(_token).balanceOf(address(this)));
      }
  
      modifier onlyGovernance() {
          require(msg.sender == GOV, "!gov");
          _;
      }
  }