Contract Source Code:

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.8.0;

// Sources flattened with hardhat v2.9.3 https://hardhat.org

// File contracts/Math/Math.sol


/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow, so we distribute
        return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
    }

    // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
    function sqrt(uint y) internal pure returns (uint z) {
        if (y > 3) {
            z = y;
            uint x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
    }
}


// File contracts/Curve/IveFXS.sol

pragma abicoder v2;

interface IveFXS {

    struct LockedBalance {
        int128 amount;
        uint256 end;
    }

    function commit_transfer_ownership(address addr) external;
    function apply_transfer_ownership() external;
    function commit_smart_wallet_checker(address addr) external;
    function apply_smart_wallet_checker() external;
    function toggleEmergencyUnlock() external;
    function recoverERC20(address token_addr, uint256 amount) external;
    function get_last_user_slope(address addr) external view returns (int128);
    function user_point_history__ts(address _addr, uint256 _idx) external view returns (uint256);
    function locked__end(address _addr) external view returns (uint256);
    function checkpoint() external;
    function deposit_for(address _addr, uint256 _value) external;
    function create_lock(uint256 _value, uint256 _unlock_time) external;
    function increase_amount(uint256 _value) external;
    function increase_unlock_time(uint256 _unlock_time) external;
    function withdraw() external;
    function balanceOf(address addr) external view returns (uint256);
    function balanceOf(address addr, uint256 _t) external view returns (uint256);
    function balanceOfAt(address addr, uint256 _block) external view returns (uint256);
    function totalSupply() external view returns (uint256);
    function totalSupply(uint256 t) external view returns (uint256);
    function totalSupplyAt(uint256 _block) external view returns (uint256);
    function totalFXSSupply() external view returns (uint256);
    function totalFXSSupplyAt(uint256 _block) external view returns (uint256);
    function changeController(address _newController) external;
    function token() external view returns (address);
    function supply() external view returns (uint256);
    function locked(address addr) external view returns (LockedBalance memory);
    function epoch() external view returns (uint256);
    function point_history(uint256 arg0) external view returns (int128 bias, int128 slope, uint256 ts, uint256 blk, uint256 fxs_amt);
    function user_point_history(address arg0, uint256 arg1) external view returns (int128 bias, int128 slope, uint256 ts, uint256 blk, uint256 fxs_amt);
    function user_point_epoch(address arg0) external view returns (uint256);
    function slope_changes(uint256 arg0) external view returns (int128);
    function controller() external view returns (address);
    function transfersEnabled() external view returns (bool);
    function emergencyUnlockActive() external view returns (bool);
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function version() external view returns (string memory);
    function decimals() external view returns (uint256);
    function future_smart_wallet_checker() external view returns (address);
    function smart_wallet_checker() external view returns (address);
    function admin() external view returns (address);
    function future_admin() external view returns (address);
}


// File contracts/Curve/IFraxGaugeController.sol


// https://github.com/swervefi/swerve/edit/master/packages/swerve-contracts/interfaces/IGaugeController.sol

interface IFraxGaugeController {
    struct Point {
        uint256 bias;
        uint256 slope;
    }

    struct VotedSlope {
        uint256 slope;
        uint256 power;
        uint256 end;
    }

    // Public variables
    function admin() external view returns (address);
    function future_admin() external view returns (address);
    function token() external view returns (address);
    function voting_escrow() external view returns (address);
    function n_gauge_types() external view returns (int128);
    function n_gauges() external view returns (int128);
    function gauge_type_names(int128) external view returns (string memory);
    function gauges(uint256) external view returns (address);
    function vote_user_slopes(address, address)
        external
        view
        returns (VotedSlope memory);
    function vote_user_power(address) external view returns (uint256);
    function last_user_vote(address, address) external view returns (uint256);
    function points_weight(address, uint256)
        external
        view
        returns (Point memory);
    function time_weight(address) external view returns (uint256);
    function points_sum(int128, uint256) external view returns (Point memory);
    function time_sum(uint256) external view returns (uint256);
    function points_total(uint256) external view returns (uint256);
    function time_total() external view returns (uint256);
    function points_type_weight(int128, uint256)
        external
        view
        returns (uint256);
    function time_type_weight(uint256) external view returns (uint256);

    // Getter functions
    function gauge_types(address) external view returns (int128);
    function gauge_relative_weight(address) external view returns (uint256);
    function gauge_relative_weight(address, uint256) external view returns (uint256);
    function get_gauge_weight(address) external view returns (uint256);
    function get_type_weight(int128) external view returns (uint256);
    function get_total_weight() external view returns (uint256);
    function get_weights_sum_per_type(int128) external view returns (uint256);

    // External functions
    function commit_transfer_ownership(address) external;
    function apply_transfer_ownership() external;
    function add_gauge(
        address,
        int128,
        uint256
    ) external;
    function checkpoint() external;
    function checkpoint_gauge(address) external;
    function global_emission_rate() external view returns (uint256);
    function gauge_relative_weight_write(address)
        external
        returns (uint256);
    function gauge_relative_weight_write(address, uint256)
        external
        returns (uint256);
    function add_type(string memory, uint256) external;
    function change_type_weight(int128, uint256) external;
    function change_gauge_weight(address, uint256) external;
    function change_global_emission_rate(uint256) external;
    function vote_for_gauge_weights(address, uint256) external;
}


// File contracts/Curve/IFraxGaugeFXSRewardsDistributor.sol


interface IFraxGaugeFXSRewardsDistributor {
  function acceptOwnership() external;
  function curator_address() external view returns(address);
  function currentReward(address gauge_address) external view returns(uint256 reward_amount);
  function distributeReward(address gauge_address) external returns(uint256 weeks_elapsed, uint256 reward_tally);
  function distributionsOn() external view returns(bool);
  function gauge_whitelist(address) external view returns(bool);
  function is_middleman(address) external view returns(bool);
  function last_time_gauge_paid(address) external view returns(uint256);
  function nominateNewOwner(address _owner) external;
  function nominatedOwner() external view returns(address);
  function owner() external view returns(address);
  function recoverERC20(address tokenAddress, uint256 tokenAmount) external;
  function setCurator(address _new_curator_address) external;
  function setGaugeController(address _gauge_controller_address) external;
  function setGaugeState(address _gauge_address, bool _is_middleman, bool _is_active) external;
  function setTimelock(address _new_timelock) external;
  function timelock_address() external view returns(address);
  function toggleDistributions() external;
}


// File contracts/Common/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 GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return payable(msg.sender);
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}


// File contracts/Math/SafeMath.sol


/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     *
     * _Available since v2.4.0._
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}


// File contracts/ERC20/IERC20.sol



/**
 * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
 * the optional functions; to access them see {ERC20Detailed}.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}


// File contracts/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
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}


// File contracts/ERC20/ERC20.sol





/**
 * @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 {ERC20Mintable}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of 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 {
    using SafeMath for uint256;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;
    
    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory __name, string memory __symbol) public {
        _name = __name;
        _symbol = __symbol;
        _decimals = 18;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * 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 returns (uint8) {
        return _decimals;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.approve(address spender, uint256 amount)
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for `sender`'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(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) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` 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 = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for `accounts`'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");

        _approve(account, _msgSender(), decreasedAllowance);
        _burn(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);

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is 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 Destroys `amount` tokens from `account`.`amount` is then deducted
     * from the caller's allowance.
     *
     * See {_burn} and {_approve}.
     */
    function _burnFrom(address account, uint256 amount) internal virtual {
        _burn(account, amount);
        _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "ERC20: burn amount exceeds allowance"));
    }

    /**
     * @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 to 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:using-hooks.adoc[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}


// File contracts/Uniswap/TransferHelper.sol


// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
    function safeApprove(address token, address to, uint value) internal {
        // bytes4(keccak256(bytes('approve(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
    }

    function safeTransfer(address token, address to, uint value) internal {
        // bytes4(keccak256(bytes('transfer(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FAILED');
    }

    function safeTransferFrom(address token, address from, address to, uint value) internal {
        // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FROM_FAILED');
    }

    function safeTransferETH(address to, uint value) internal {
        (bool success,) = to.call{value:value}(new bytes(0));
        require(success, 'TransferHelper: ETH_TRANSFER_FAILED');
    }
}


// File contracts/ERC20/SafeERC20.sol




/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}


// File contracts/Utils/ReentrancyGuard.sol


/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor () internal {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}


// File contracts/Staking/Owned.sol


// https://docs.synthetix.io/contracts/Owned
contract Owned {
    address public owner;
    address public nominatedOwner;

    constructor (address _owner) public {
        require(_owner != address(0), "Owner address cannot be 0");
        owner = _owner;
        emit OwnerChanged(address(0), _owner);
    }

    function nominateNewOwner(address _owner) external onlyOwner {
        nominatedOwner = _owner;
        emit OwnerNominated(_owner);
    }

    function acceptOwnership() external {
        require(msg.sender == nominatedOwner, "You must be nominated before you can accept ownership");
        emit OwnerChanged(owner, nominatedOwner);
        owner = nominatedOwner;
        nominatedOwner = address(0);
    }

    modifier onlyOwner {
        require(msg.sender == owner, "Only the contract owner may perform this action");
        _;
    }

    event OwnerNominated(address newOwner);
    event OwnerChanged(address oldOwner, address newOwner);
}


// File contracts/Misc_AMOs/convex/IConvexBaseRewardPool.sol


interface IConvexBaseRewardPool {
  function addExtraReward(address _reward) external returns (bool);
  function balanceOf(address account) external view returns (uint256);
  function clearExtraRewards() external;
  function currentRewards() external view returns (uint256);
  function donate(uint256 _amount) external returns (bool);
  function duration() external view returns (uint256);
  function earned(address account) external view returns (uint256);
  function extraRewards(uint256) external view returns (address);
  function extraRewardsLength() external view returns (uint256);
  function getReward() external returns (bool);
  function getReward(address _account, bool _claimExtras) external returns (bool);
  function historicalRewards() external view returns (uint256);
  function lastTimeRewardApplicable() external view returns (uint256);
  function lastUpdateTime() external view returns (uint256);
  function newRewardRatio() external view returns (uint256);
  function operator() external view returns (address);
  function periodFinish() external view returns (uint256);
  function pid() external view returns (uint256);
  function queueNewRewards(uint256 _rewards) external returns (bool);
  function queuedRewards() external view returns (uint256);
  function rewardManager() external view returns (address);
  function rewardPerToken() external view returns (uint256);
  function rewardPerTokenStored() external view returns (uint256);
  function rewardRate() external view returns (uint256);
  function rewardToken() external view returns (address);
  function rewards(address) external view returns (uint256);
  function stake(uint256 _amount) external returns (bool);
  function stakeAll() external returns (bool);
  function stakeFor(address _for, uint256 _amount) external returns (bool);
  function stakingToken() external view returns (address);
  function totalSupply() external view returns (uint256);
  function userRewardPerTokenPaid(address) external view returns (uint256);
  function withdraw(uint256 amount, bool claim) external returns (bool);
  function withdrawAll(bool claim) external;
  function withdrawAllAndUnwrap(bool claim) external;
  function withdrawAndUnwrap(uint256 amount, bool claim) external returns (bool);
}


// File contracts/Staking/FraxUnifiedFarmTemplate.sol

pragma experimental ABIEncoderV2;

// ====================================================================
// |     ______                   _______                             |
// |    / _____________ __  __   / ____(_____  ____ _____  ________   |
// |   / /_  / ___/ __ `| |/_/  / /_  / / __ \/ __ `/ __ \/ ___/ _ \  |
// |  / __/ / /  / /_/ _>  <   / __/ / / / / / /_/ / / / / /__/  __/  |
// | /_/   /_/   \__,_/_/|_|  /_/   /_/_/ /_/\__,_/_/ /_/\___/\___/   |
// |                                                                  |
// ====================================================================
// ====================== FraxUnifiedFarmTemplate =====================
// ====================================================================
// Migratable Farming contract that accounts for veFXS
// Overrideable for UniV3, ERC20s, etc
// New for V2
//      - Multiple reward tokens possible
//      - Can add to existing locked stakes
//      - Contract is aware of proxied veFXS
//      - veFXS multiplier formula changed
// Apes together strong

// Frax Finance: https://github.com/FraxFinance

// Primary Author(s)
// Travis Moore: https://github.com/FortisFortuna

// Reviewer(s) / Contributor(s)
// Jason Huan: https://github.com/jasonhuan
// Sam Kazemian: https://github.com/samkazemian
// Dennis: github.com/denett
// Sam Sun: https://github.com/samczsun

// Originally inspired by Synthetix.io, but heavily modified by the Frax team
// (Locked, veFXS, and UniV3 portions are new)
// https://raw.githubusercontent.com/Synthetixio/synthetix/develop/contracts/StakingRewards.sol









// Extra rewards

contract FraxUnifiedFarmTemplate is Owned, ReentrancyGuard {
    using SafeERC20 for ERC20;

    /* ========== STATE VARIABLES ========== */

    // Instances
    IveFXS private veFXS = IveFXS(0xc8418aF6358FFddA74e09Ca9CC3Fe03Ca6aDC5b0);
    
    // Frax related
    address internal constant frax_address = 0x853d955aCEf822Db058eb8505911ED77F175b99e;
    bool internal frax_is_token0;
    uint256 public fraxPerLPStored;

    // Constant for various precisions
    uint256 internal constant MULTIPLIER_PRECISION = 1e18;

    // Time tracking
    uint256 public periodFinish;
    uint256 public lastUpdateTime;

    // Lock time and multiplier settings
    uint256 public lock_max_multiplier = uint256(3e18); // E18. 1x = e18
    uint256 public lock_time_for_max_multiplier = 3 * 365 * 86400; // 3 years
    // uint256 public lock_time_for_max_multiplier = 2 * 86400; // 2 days
    uint256 public lock_time_min = 86400; // 1 * 86400  (1 day)

    // veFXS related
    uint256 public vefxs_boost_scale_factor = uint256(4e18); // E18. 4x = 4e18; 100 / scale_factor = % vefxs supply needed for max boost
    uint256 public vefxs_max_multiplier = uint256(2e18); // E18. 1x = 1e18
    uint256 public vefxs_per_frax_for_max_boost = uint256(2e18); // E18. 2e18 means 2 veFXS must be held by the staker per 1 FRAX
    mapping(address => uint256) internal _vefxsMultiplierStored;
    mapping(address => bool) internal valid_vefxs_proxies;
    mapping(address => mapping(address => bool)) internal proxy_allowed_stakers;

    // Reward addresses, gauge addresses, reward rates, and reward managers
    mapping(address => address) public rewardManagers; // token addr -> manager addr
    address[] internal rewardTokens;
    address[] internal gaugeControllers;
    address[] internal rewardDistributors;
    uint256[] internal rewardRatesManual;
    mapping(address => uint256) public rewardTokenAddrToIdx; // token addr -> token index
    
    // Reward period
    uint256 public constant rewardsDuration = 604800; // 7 * 86400  (7 days)

    // Reward tracking
    uint256[] private rewardsPerTokenStored;
    mapping(address => mapping(uint256 => uint256)) private userRewardsPerTokenPaid; // staker addr -> token id -> paid amount
    mapping(address => mapping(uint256 => uint256)) private rewards; // staker addr -> token id -> reward amount
    mapping(address => uint256) internal lastRewardClaimTime; // staker addr -> timestamp
    
    // Gauge tracking
    uint256[] private last_gauge_relative_weights;
    uint256[] private last_gauge_time_totals;

    // Balance tracking
    uint256 internal _total_liquidity_locked;
    uint256 internal _total_combined_weight;
    mapping(address => uint256) internal _locked_liquidity;
    mapping(address => uint256) internal _combined_weights;
    mapping(address => uint256) public proxy_lp_balances; // Keeps track of LP balances proxy-wide. Needed to make sure the proxy boost is kept in line

    // List of valid migrators (set by governance)
    mapping(address => bool) internal valid_migrators;

    // Stakers set which migrator(s) they want to use
    mapping(address => mapping(address => bool)) internal staker_allowed_migrators;
    mapping(address => address) public staker_designated_proxies; // Keep public so users can see on the frontend if they have a proxy

    // Admin booleans for emergencies, migrations, and overrides
    bool public stakesUnlocked; // Release locked stakes in case of emergency
    bool internal migrationsOn; // Used for migrations. Prevents new stakes, but allows LP and reward withdrawals
    bool internal withdrawalsPaused; // For emergencies
    bool internal rewardsCollectionPaused; // For emergencies
    bool internal stakingPaused; // For emergencies

    /* ========== STRUCTS ========== */
    // In children...


    /* ========== MODIFIERS ========== */

    modifier onlyByOwnGov() {
        require(msg.sender == owner || msg.sender == 0x8412ebf45bAC1B340BbE8F318b928C466c4E39CA, "Not owner or timelock");
        _;
    }

    modifier onlyTknMgrs(address reward_token_address) {
        require(msg.sender == owner || isTokenManagerFor(msg.sender, reward_token_address), "Not owner or tkn mgr");
        _;
    }

    modifier isMigrating() {
        require(migrationsOn == true, "Not in migration");
        _;
    }

    modifier updateRewardAndBalance(address account, bool sync_too) {
        _updateRewardAndBalance(account, sync_too);
        _;
    }

    /* ========== CONSTRUCTOR ========== */

    constructor (
        address _owner,
        address[] memory _rewardTokens,
        address[] memory _rewardManagers,
        uint256[] memory _rewardRatesManual,
        address[] memory _gaugeControllers,
        address[] memory _rewardDistributors
    ) Owned(_owner) {

        // Address arrays
        rewardTokens = _rewardTokens;
        gaugeControllers = _gaugeControllers;
        rewardDistributors = _rewardDistributors;
        rewardRatesManual = _rewardRatesManual;

        for (uint256 i = 0; i < _rewardTokens.length; i++){ 
            // For fast token address -> token ID lookups later
            rewardTokenAddrToIdx[_rewardTokens[i]] = i;

            // Initialize the stored rewards
            rewardsPerTokenStored.push(0);

            // Initialize the reward managers
            rewardManagers[_rewardTokens[i]] = _rewardManagers[i];

            // Push in empty relative weights to initialize the array
            last_gauge_relative_weights.push(0);

            // Push in empty time totals to initialize the array
            last_gauge_time_totals.push(0);
        }

        // Other booleans
        stakesUnlocked = false;

        // Initialization
        lastUpdateTime = block.timestamp;
        periodFinish = block.timestamp + rewardsDuration;
    }

    /* ============= VIEWS ============= */

    // ------ REWARD RELATED ------

    // See if the caller_addr is a manager for the reward token 
    function isTokenManagerFor(address caller_addr, address reward_token_addr) public view returns (bool){
        if (caller_addr == owner) return true; // Contract owner
        else if (rewardManagers[reward_token_addr] == caller_addr) return true; // Reward manager
        return false; 
    }

    // All the reward tokens
    function getAllRewardTokens() external view returns (address[] memory) {
        return rewardTokens;
    }

    // Last time the reward was applicable
    function lastTimeRewardApplicable() internal view returns (uint256) {
        return Math.min(block.timestamp, periodFinish);
    }

    function rewardRates(uint256 token_idx) public view returns (uint256 rwd_rate) {
        address gauge_controller_address = gaugeControllers[token_idx];
        if (gauge_controller_address != address(0)) {
            rwd_rate = (IFraxGaugeController(gauge_controller_address).global_emission_rate() * last_gauge_relative_weights[token_idx]) / 1e18;
        }
        else {
            rwd_rate = rewardRatesManual[token_idx];
        }
    }

    // Amount of reward tokens per LP token / liquidity unit
    function rewardsPerToken() public view returns (uint256[] memory newRewardsPerTokenStored) {
        if (_total_liquidity_locked == 0 || _total_combined_weight == 0) {
            return rewardsPerTokenStored;
        }
        else {
            newRewardsPerTokenStored = new uint256[](rewardTokens.length);
            for (uint256 i = 0; i < rewardsPerTokenStored.length; i++){ 
                newRewardsPerTokenStored[i] = rewardsPerTokenStored[i] + (
                    ((lastTimeRewardApplicable() - lastUpdateTime) * rewardRates(i) * 1e18) / _total_combined_weight
                );
            }
            return newRewardsPerTokenStored;
        }
    }

    // Amount of reward tokens an account has earned / accrued
    // Note: In the edge-case of one of the account's stake expiring since the last claim, this will
    // return a slightly inflated number
    function earned(address account) public view returns (uint256[] memory new_earned) {
        uint256[] memory reward_arr = rewardsPerToken();
        new_earned = new uint256[](rewardTokens.length);

        if (_combined_weights[account] > 0){
            for (uint256 i = 0; i < rewardTokens.length; i++){ 
                new_earned[i] = ((_combined_weights[account] * (reward_arr[i] - userRewardsPerTokenPaid[account][i])) / 1e18)
                                + rewards[account][i];
            }
        }
    }

    // Total reward tokens emitted in the given period
    function getRewardForDuration() external view returns (uint256[] memory rewards_per_duration_arr) {
        rewards_per_duration_arr = new uint256[](rewardRatesManual.length);

        for (uint256 i = 0; i < rewardRatesManual.length; i++){ 
            rewards_per_duration_arr[i] = rewardRates(i) * rewardsDuration;
        }
    }


    // ------ LIQUIDITY AND WEIGHTS ------

    // User locked liquidity / LP tokens
    function totalLiquidityLocked() external view returns (uint256) {
        return _total_liquidity_locked;
    }

    // Total locked liquidity / LP tokens
    function lockedLiquidityOf(address account) external view returns (uint256) {
        return _locked_liquidity[account];
    }

    // Total combined weight
    function totalCombinedWeight() external view returns (uint256) {
        return _total_combined_weight;
    }

    // Total 'balance' used for calculating the percent of the pool the account owns
    // Takes into account the locked stake time multiplier and veFXS multiplier
    function combinedWeightOf(address account) external view returns (uint256) {
        return _combined_weights[account];
    }

    // Calculated the combined weight for an account
    function calcCurCombinedWeight(address account) public virtual view 
        returns (
            uint256 old_combined_weight,
            uint256 new_vefxs_multiplier,
            uint256 new_combined_weight
        )
    {
        revert("Need cCCW logic");
    }

    // ------ LOCK RELATED ------

    // Multiplier amount, given the length of the lock
    function lockMultiplier(uint256 secs) public view returns (uint256) {
        return Math.min(
            lock_max_multiplier,
            uint256(MULTIPLIER_PRECISION) + (
                (secs * (lock_max_multiplier - MULTIPLIER_PRECISION)) / lock_time_for_max_multiplier
            )
        ) ;
    }

    // ------ FRAX RELATED ------

    function userStakedFrax(address account) public view returns (uint256) {
        return (fraxPerLPStored * _locked_liquidity[account]) / MULTIPLIER_PRECISION;
    }

    function proxyStakedFrax(address proxy_address) public view returns (uint256) {
        return (fraxPerLPStored * proxy_lp_balances[proxy_address]) / MULTIPLIER_PRECISION;
    }

    // Max LP that can get max veFXS boosted for a given address at its current veFXS balance
    function maxLPForMaxBoost(address account) external view returns (uint256) {
        return (veFXS.balanceOf(account) * MULTIPLIER_PRECISION * MULTIPLIER_PRECISION) / (vefxs_per_frax_for_max_boost * fraxPerLPStored);
    }

    // Meant to be overridden
    function fraxPerLPToken() public virtual view returns (uint256) {
        revert("Need fPLPT logic");
    }

    // ------ veFXS RELATED ------

    function minVeFXSForMaxBoost(address account) public view returns (uint256) {
        return (userStakedFrax(account) * vefxs_per_frax_for_max_boost) / MULTIPLIER_PRECISION;
    }

    function minVeFXSForMaxBoostProxy(address proxy_address) public view returns (uint256) {
        return (proxyStakedFrax(proxy_address) * vefxs_per_frax_for_max_boost) / MULTIPLIER_PRECISION;
    }

    function getProxyFor(address addr) public view returns (address){
        if (valid_vefxs_proxies[addr]) {
            // If addr itself is a proxy, return that.
            // If it farms itself directly, it should use the shared LP tally in proxyStakedFrax
            return addr;
        }
        else {
            // Otherwise, return the proxy, or address(0)
            return staker_designated_proxies[addr];
        }
    }

    function veFXSMultiplier(address account) public view returns (uint256 vefxs_multiplier) {
        // Use either the user's or their proxy's veFXS balance
        uint256 vefxs_bal_to_use = 0;
        address the_proxy = getProxyFor(account);
        vefxs_bal_to_use = (the_proxy == address(0)) ? veFXS.balanceOf(account) : veFXS.balanceOf(the_proxy);

        // First option based on fraction of total veFXS supply, with an added scale factor
        uint256 mult_optn_1 = (vefxs_bal_to_use * vefxs_max_multiplier * vefxs_boost_scale_factor) 
                            / (veFXS.totalSupply() * MULTIPLIER_PRECISION);
        
        // Second based on old method, where the amount of FRAX staked comes into play
        uint256 mult_optn_2;
        {
            uint256 veFXS_needed_for_max_boost;

            // Need to use proxy-wide FRAX balance if applicable, to prevent exploiting
            veFXS_needed_for_max_boost = (the_proxy == address(0)) ? minVeFXSForMaxBoost(account) : minVeFXSForMaxBoostProxy(the_proxy);

            if (veFXS_needed_for_max_boost > 0){ 
                uint256 user_vefxs_fraction = (vefxs_bal_to_use * MULTIPLIER_PRECISION) / veFXS_needed_for_max_boost;
                
                mult_optn_2 = (user_vefxs_fraction * vefxs_max_multiplier) / MULTIPLIER_PRECISION;
            }
            else mult_optn_2 = 0; // This will happen with the first stake, when user_staked_frax is 0
        }

        // Select the higher of the two
        vefxs_multiplier = (mult_optn_1 > mult_optn_2 ? mult_optn_1 : mult_optn_2);

        // Cap the boost to the vefxs_max_multiplier
        if (vefxs_multiplier > vefxs_max_multiplier) vefxs_multiplier = vefxs_max_multiplier;
    }

    /* =============== MUTATIVE FUNCTIONS =============== */

    // ------ MIGRATIONS ------

    // Staker can allow a migrator 
    function stakerToggleMigrator(address migrator_address) external {
        require(valid_migrators[migrator_address], "Invalid migrator address");
        staker_allowed_migrators[msg.sender][migrator_address] = !staker_allowed_migrators[msg.sender][migrator_address]; 
    }

    // Proxy can allow a staker to use their veFXS balance (the staker will have to reciprocally toggle them too)
    // Must come before stakerSetVeFXSProxy
    function proxyToggleStaker(address staker_address) external {
        require(valid_vefxs_proxies[msg.sender], "Invalid proxy");
        proxy_allowed_stakers[msg.sender][staker_address] = !proxy_allowed_stakers[msg.sender][staker_address]; 

        // Disable the staker's set proxy if it was the toggler and is currently on
        if (staker_designated_proxies[staker_address] == msg.sender){
            staker_designated_proxies[staker_address] = address(0); 

            // Remove the LP as well
            proxy_lp_balances[msg.sender] -= _locked_liquidity[staker_address];
        }
    }

    // Staker can allow a veFXS proxy (the proxy will have to toggle them first)
    function stakerSetVeFXSProxy(address proxy_address) external {
        require(valid_vefxs_proxies[proxy_address], "Invalid proxy");
        require(proxy_allowed_stakers[proxy_address][msg.sender], "Proxy has not allowed you yet");
        staker_designated_proxies[msg.sender] = proxy_address; 

        // Add the the LP as well
        proxy_lp_balances[proxy_address] += _locked_liquidity[msg.sender];
    }

    // ------ STAKING ------
    // In children...


    // ------ WITHDRAWING ------
    // In children...


    // ------ REWARDS SYNCING ------

    function _updateRewardAndBalance(address account, bool sync_too) internal {
        // Need to retro-adjust some things if the period hasn't been renewed, then start a new one
        if (sync_too){
            sync();
        }
        
        if (account != address(0)) {
            // To keep the math correct, the user's combined weight must be recomputed to account for their
            // ever-changing veFXS balance.
            (   
                uint256 old_combined_weight,
                uint256 new_vefxs_multiplier,
                uint256 new_combined_weight
            ) = calcCurCombinedWeight(account);

            // Calculate the earnings first
            _syncEarned(account);

            // Update the user's stored veFXS multipliers
            _vefxsMultiplierStored[account] = new_vefxs_multiplier;

            // Update the user's and the global combined weights
            if (new_combined_weight >= old_combined_weight) {
                uint256 weight_diff = new_combined_weight - old_combined_weight;
                _total_combined_weight = _total_combined_weight + weight_diff;
                _combined_weights[account] = old_combined_weight + weight_diff;
            } else {
                uint256 weight_diff = old_combined_weight - new_combined_weight;
                _total_combined_weight = _total_combined_weight - weight_diff;
                _combined_weights[account] = old_combined_weight - weight_diff;
            }

        }
    }

    function _syncEarned(address account) internal {
        if (account != address(0)) {
            // Calculate the earnings
            uint256[] memory earned_arr = earned(account);

            // Update the rewards array
            for (uint256 i = 0; i < earned_arr.length; i++){ 
                rewards[account][i] = earned_arr[i];
            }

            // Update the rewards paid array
            for (uint256 i = 0; i < earned_arr.length; i++){ 
                userRewardsPerTokenPaid[account][i] = rewardsPerTokenStored[i];
            }
        }
    }


    // ------ REWARDS CLAIMING ------

    function getRewardExtraLogic(address destination_address) public nonReentrant {
        require(rewardsCollectionPaused == false, "Rewards collection paused");
        return _getRewardExtraLogic(msg.sender, destination_address);
    }

    function _getRewardExtraLogic(address rewardee, address destination_address) internal virtual {
        revert("Need gREL logic");
    }

    // Two different getReward functions are needed because of delegateCall and msg.sender issues
    // For backwards-compatibility
    function getReward(address destination_address) external nonReentrant returns (uint256[] memory) {
        return _getReward(msg.sender, destination_address, true);
    }

    function getReward2(address destination_address, bool claim_extra_too) external nonReentrant returns (uint256[] memory) {
        return _getReward(msg.sender, destination_address, claim_extra_too);
    }

    // No withdrawer == msg.sender check needed since this is only internally callable
    function _getReward(address rewardee, address destination_address, bool do_extra_logic) internal updateRewardAndBalance(rewardee, true) returns (uint256[] memory rewards_before) {
        // Make sure rewards collection isn't paused
        require(rewardsCollectionPaused == false, "Rewards collection paused");
        
        // Update the rewards array and distribute rewards
        rewards_before = new uint256[](rewardTokens.length);

        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            rewards_before[i] = rewards[rewardee][i];
            rewards[rewardee][i] = 0;
            if (rewards_before[i] > 0) TransferHelper.safeTransfer(rewardTokens[i], destination_address, rewards_before[i]);
        }

        // Handle additional reward logic
        if (do_extra_logic) {
            _getRewardExtraLogic(rewardee, destination_address);
        }

        // Update the last reward claim time
        lastRewardClaimTime[rewardee] = block.timestamp;
    }


    // ------ FARM SYNCING ------

    // If the period expired, renew it
    function retroCatchUp() internal {
        // Pull in rewards from the rewards distributor, if applicable
        for (uint256 i = 0; i < rewardDistributors.length; i++){ 
            address reward_distributor_address = rewardDistributors[i];
            if (reward_distributor_address != address(0)) {
                IFraxGaugeFXSRewardsDistributor(reward_distributor_address).distributeReward(address(this));
            }
        }

        // Ensure the provided reward amount is not more than the balance in the contract.
        // This keeps the reward rate in the right range, preventing overflows due to
        // very high values of rewardRate in the earned and rewardsPerToken functions;
        // Reward + leftover must be less than 2^256 / 10^18 to avoid overflow.
        uint256 num_periods_elapsed = uint256(block.timestamp - periodFinish) / rewardsDuration; // Floor division to the nearest period
        
        // Make sure there are enough tokens to renew the reward period
        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            require((rewardRates(i) * rewardsDuration * (num_periods_elapsed + 1)) <= ERC20(rewardTokens[i]).balanceOf(address(this)), string(abi.encodePacked("Not enough reward tokens available: ", rewardTokens[i])) );
        }
        
        // uint256 old_lastUpdateTime = lastUpdateTime;
        // uint256 new_lastUpdateTime = block.timestamp;

        // lastUpdateTime = periodFinish;
        periodFinish = periodFinish + ((num_periods_elapsed + 1) * rewardsDuration);

        // Update the rewards and time
        _updateStoredRewardsAndTime();

        // Update the fraxPerLPStored
        fraxPerLPStored = fraxPerLPToken();

        // Pull in rewards and set the reward rate for one week, based off of that
        // If the rewards get messed up for some reason, set this to 0 and it will skip
        // if (rewardRatesManual[1] != 0 && rewardRatesManual[2] != 0) {
        //     // CRV & CVX
        //     // ====================================
        //     uint256 crv_before = ERC20(rewardTokens[1]).balanceOf(address(this));
        //     uint256 cvx_before = ERC20(rewardTokens[2]).balanceOf(address(this));
        //     IConvexBaseRewardPool(0x329cb014b562d5d42927cfF0dEdF4c13ab0442EF).getReward(
        //         address(this),
        //         true
        //     );
        //     uint256 crv_after = ERC20(rewardTokens[1]).balanceOf(address(this));
        //     uint256 cvx_after = ERC20(rewardTokens[2]).balanceOf(address(this));

        //     // Set the new reward rate
        //     rewardRatesManual[1] = (crv_after - crv_before) / rewardsDuration;
        //     rewardRatesManual[2] = (cvx_after - cvx_before) / rewardsDuration;
        // }

    }

    function _updateStoredRewardsAndTime() internal {
        // Get the rewards
        uint256[] memory rewards_per_token = rewardsPerToken();

        // Update the rewardsPerTokenStored
        for (uint256 i = 0; i < rewardsPerTokenStored.length; i++){ 
            rewardsPerTokenStored[i] = rewards_per_token[i];
        }

        // Update the last stored time
        lastUpdateTime = lastTimeRewardApplicable();
    }

    function sync_gauge_weights(bool force_update) public {
        // Loop through the gauge controllers
        for (uint256 i = 0; i < gaugeControllers.length; i++){ 
            address gauge_controller_address = gaugeControllers[i];
            if (gauge_controller_address != address(0)) {
                if (force_update || (block.timestamp > last_gauge_time_totals[i])){
                    // Update the gauge_relative_weight
                    last_gauge_relative_weights[i] = IFraxGaugeController(gauge_controller_address).gauge_relative_weight_write(address(this), block.timestamp);
                    last_gauge_time_totals[i] = IFraxGaugeController(gauge_controller_address).time_total();
                }
            }
        }
    }

    function sync() public {
        // Sync the gauge weight, if applicable
        sync_gauge_weights(false);

        // Update the fraxPerLPStored
        fraxPerLPStored = fraxPerLPToken();

        if (block.timestamp >= periodFinish) {
            retroCatchUp();
        }
        else {
            _updateStoredRewardsAndTime();
        }
    }

    /* ========== RESTRICTED FUNCTIONS - Curator / migrator callable ========== */
    
    // ------ FARM SYNCING ------
    // In children...

    // ------ PAUSES ------

    function setPauses(
        bool _stakingPaused,
        bool _withdrawalsPaused,
        bool _rewardsCollectionPaused
    ) external onlyByOwnGov {
        stakingPaused = _stakingPaused;
        withdrawalsPaused = _withdrawalsPaused;
        rewardsCollectionPaused = _rewardsCollectionPaused;
    }

    /* ========== RESTRICTED FUNCTIONS - Owner or timelock only ========== */
    
    function unlockStakes() external onlyByOwnGov {
        stakesUnlocked = !stakesUnlocked;
    }

    function toggleMigrations() external onlyByOwnGov {
        migrationsOn = !migrationsOn;
    }

    // Adds supported migrator address
    function toggleMigrator(address migrator_address) external onlyByOwnGov {
        valid_migrators[migrator_address] = !valid_migrators[migrator_address];
    }

    // Adds a valid veFXS proxy address
    function toggleValidVeFXSProxy(address _proxy_addr) external onlyByOwnGov {
        valid_vefxs_proxies[_proxy_addr] = !valid_vefxs_proxies[_proxy_addr];
    }

    // Added to support recovering LP Rewards and other mistaken tokens from other systems to be distributed to holders
    function recoverERC20(address tokenAddress, uint256 tokenAmount) external onlyTknMgrs(tokenAddress) {
        // Check if the desired token is a reward token
        bool isRewardToken = false;
        for (uint256 i = 0; i < rewardTokens.length; i++){ 
            if (rewardTokens[i] == tokenAddress) {
                isRewardToken = true;
                break;
            }
        }

        // Only the reward managers can take back their reward tokens
        // Also, other tokens, like the staking token, airdrops, or accidental deposits, can be withdrawn by the owner
        if (
                (isRewardToken && rewardManagers[tokenAddress] == msg.sender)
                || (!isRewardToken && (msg.sender == owner))
            ) {
            TransferHelper.safeTransfer(tokenAddress, msg.sender, tokenAmount);
            return;
        }
        // If none of the above conditions are true
        else {
            revert("No valid tokens to recover");
        }
    }

    function setMiscVariables(
        uint256[6] memory _misc_vars
        // [0]: uint256 _lock_max_multiplier, 
        // [1] uint256 _vefxs_max_multiplier, 
        // [2] uint256 _vefxs_per_frax_for_max_boost,
        // [3] uint256 _vefxs_boost_scale_factor,
        // [4] uint256 _lock_time_for_max_multiplier,
        // [5] uint256 _lock_time_min
    ) external onlyByOwnGov {
        require(_misc_vars[0] >= MULTIPLIER_PRECISION, "Must be >= MUL PREC");
        require((_misc_vars[1] >= 0) && (_misc_vars[2] >= 0) && (_misc_vars[3] >= 0), "Must be >= 0");
        require((_misc_vars[4] >= 1) && (_misc_vars[5] >= 1), "Must be >= 1");

        lock_max_multiplier = _misc_vars[0];
        vefxs_max_multiplier = _misc_vars[1];
        vefxs_per_frax_for_max_boost = _misc_vars[2];
        vefxs_boost_scale_factor = _misc_vars[3];
        lock_time_for_max_multiplier = _misc_vars[4];
        lock_time_min = _misc_vars[5];
    }

    // The owner or the reward token managers can set reward rates 
    function setRewardVars(address reward_token_address, uint256 _new_rate, address _gauge_controller_address, address _rewards_distributor_address) external onlyTknMgrs(reward_token_address) {
        rewardRatesManual[rewardTokenAddrToIdx[reward_token_address]] = _new_rate;
        gaugeControllers[rewardTokenAddrToIdx[reward_token_address]] = _gauge_controller_address;
        rewardDistributors[rewardTokenAddrToIdx[reward_token_address]] = _rewards_distributor_address;
    }

    // The owner or the reward token managers can change managers
    function changeTokenManager(address reward_token_address, address new_manager_address) external onlyTknMgrs(reward_token_address) {
        rewardManagers[reward_token_address] = new_manager_address;
    }

    /* ========== A CHICKEN ========== */
    //
    //         ,~.
    //      ,-'__ `-,
    //     {,-'  `. }              ,')
    //    ,( a )   `-.__         ,',')~,
    //   <=.) (         `-.__,==' ' ' '}
    //     (   )                      /)
    //      `-'\   ,                    )
    //          |  \        `~.        /
    //          \   `._        \      /
    //           \     `._____,'    ,'
    //            `-.             ,'
    //               `-._     _,-'
    //                   77jj'
    //                  //_||
    //               __//--'/`
    //             ,--'/`  '
    //
    // [hjw] https://textart.io/art/vw6Sa3iwqIRGkZsN1BC2vweF/chicken
}


// File contracts/Misc_AMOs/convex/IConvexStakingWrapperFrax.sol


interface IConvexStakingWrapperFrax {
  function addRewards() external;
  function allowance(address owner, address spender) external view returns (uint256);
  function approve(address spender, uint256 amount) external returns (bool);
  function balanceOf(address account) external view returns (uint256);
  function collateralVault() external view returns (address);
  function convexBooster() external view returns (address);
  function convexPool() external view returns (address);
  function convexPoolId() external view returns (uint256);
  function convexToken() external view returns (address);
  function crv() external view returns (address);
  function curveToken() external view returns (address);
  function cvx() external view returns (address);
  function decimals() external view returns (uint8);
  function decreaseAllowance(address spender, uint256 subtractedValue) external returns (bool);
  function deposit(uint256 _amount, address _to) external;
//   function earned(address _account) external view returns (tuple[] memory claimable);
  function getReward(address _account, address _forwardTo) external;
  function getReward(address _account) external;
  function increaseAllowance(address spender, uint256 addedValue) external returns (bool);
  function initialize(address _curveToken, address _convexToken, address _convexPool, uint256 _poolId, address _vault) external;
  function isInit() external view returns (bool);
  function isShutdown() external view returns (bool);
  function name() external view returns (string memory);
  function owner() external view returns (address);
  function registeredRewards(address) external view returns (uint256);
  function renounceOwnership() external;
  function rewardLength() external view returns (uint256);
  function rewards(uint256) external view returns (address reward_token, address reward_pool, uint128 reward_integral, uint128 reward_remaining);
  function setApprovals() external;
  function setVault(address _vault) external;
  function shutdown() external;
  function stake(uint256 _amount, address _to) external;
  function symbol() external view returns (string memory);
  function totalBalanceOf(address _account) external view returns (uint256);
  function totalSupply() external view returns (uint256);
  function transfer(address recipient, uint256 amount) external returns (bool);
  function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
  function transferOwnership(address newOwner) external;
  function user_checkpoint(address[2] memory _accounts) external returns (bool);
  function withdraw(uint256 _amount) external;
  function withdrawAndUnwrap(uint256 _amount) external;
}


// File contracts/Misc_AMOs/convex/IDepositToken.sol


interface IDepositToken {
  function allowance(address owner, address spender) external view returns (uint256);
  function approve(address spender, uint256 amount) external returns (bool);
  function balanceOf(address account) external view returns (uint256);
  function burn(address _from, uint256 _amount) external;
  function decimals() external view returns (uint8);
  function decreaseAllowance(address spender, uint256 subtractedValue) external returns (bool);
  function increaseAllowance(address spender, uint256 addedValue) external returns (bool);
  function mint(address _to, uint256 _amount) external;
  function name() external view returns (string memory);
  function operator() external view returns (address);
  function symbol() external view returns (string memory);
  function totalSupply() external view returns (uint256);
  function transfer(address recipient, uint256 amount) external returns (bool);
  function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
}


// File contracts/Misc_AMOs/curve/I2pool.sol


interface I2pool {
    function decimals() external view returns (uint256);
    function transfer(address _to, uint256 _value) external returns (bool);
    function transferFrom(address _from, address _to, uint256 _value) external returns (bool);
    function approve(address _spender, uint256 _value) external returns (bool);
    function A() external view returns (uint256);
    function A_precise() external view returns (uint256);
    function get_virtual_price() external view returns (uint256);
    function calc_token_amount(uint256[2] memory _amounts, bool _is_deposit) external view returns (uint256);
    function add_liquidity(uint256[2] memory _amounts, uint256 _min_mint_amount) external returns (uint256);
    function get_dy(int128 i, int128 j, uint256 _dx) external view returns (uint256);
    function exchange(int128 i, int128 j, uint256 _dx, uint256 _min_dy) external returns (uint256);
    function remove_liquidity(uint256 _amount, uint256[2] memory _min_amounts) external returns (uint256[2] memory);
    function remove_liquidity_imbalance(uint256[2] memory _amounts, uint256 _max_burn_amount) external returns (uint256);
    function calc_withdraw_one_coin(uint256 _token_amount, int128 i) external view returns (uint256);
    function remove_liquidity_one_coin(uint256 _token_amount, int128 i, uint256 _min_amount) external returns (uint256);
    function ramp_A(uint256 _future_A, uint256 _future_time) external;
    function stop_ramp_A() external;
    function commit_new_fee(uint256 _new_fee, uint256 _new_admin_fee) external;
    function apply_new_fee() external;
    function revert_new_parameters() external;
    function commit_transfer_ownership(address _owner) external;
    function apply_transfer_ownership() external;
    function revert_transfer_ownership() external;
    function admin_balances(uint256 i) external view returns (uint256);
    function withdraw_admin_fees() external;
    function donate_admin_fees() external;
    function kill_me() external;
    function unkill_me() external;
    function coins(uint256 arg0) external view returns (address);
    function balances(uint256 arg0) external view returns (uint256);
    function fee() external view returns (uint256);
    function admin_fee() external view returns (uint256);
    function owner() external view returns (address);
    function initial_A() external view returns (uint256);
    function future_A() external view returns (uint256);
    function initial_A_time() external view returns (uint256);
    function future_A_time() external view returns (uint256);
    function admin_actions_deadline() external view returns (uint256);
    function transfer_ownership_deadline() external view returns (uint256);
    function future_fee() external view returns (uint256);
    function future_admin_fee() external view returns (uint256);
    function future_owner() external view returns (address);
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function balanceOf(address arg0) external view returns (uint256);
    function allowance(address arg0, address arg1) external view returns (uint256);
    function totalSupply() external view returns (uint256);
}


// File contracts/Staking/FraxUnifiedFarm_ERC20.sol

// ====================================================================
// |     ______                   _______                             |
// |    / _____________ __  __   / ____(_____  ____ _____  ________   |
// |   / /_  / ___/ __ `| |/_/  / /_  / / __ \/ __ `/ __ \/ ___/ _ \  |
// |  / __/ / /  / /_/ _>  <   / __/ / / / / / /_/ / / / / /__/  __/  |
// | /_/   /_/   \__,_/_/|_|  /_/   /_/_/ /_/\__,_/_/ /_/\___/\___/   |
// |                                                                  |
// ====================================================================
// ======================= FraxUnifiedFarm_ERC20 ======================
// ====================================================================
// For ERC20 Tokens
// Uses FraxUnifiedFarmTemplate.sol

// -------------------- VARIES --------------------

// Convex stkcvxFPIFRAX



// G-UNI
// import "../Misc_AMOs/gelato/IGUniPool.sol";

// mStable
// import '../Misc_AMOs/mstable/IFeederPool.sol';

// StakeDAO sdETH-FraxPut
// import '../Misc_AMOs/stakedao/IOpynPerpVault.sol';

// StakeDAO Vault
// import '../Misc_AMOs/stakedao/IStakeDaoVault.sol';

// Uniswap V2
// import '../Uniswap/Interfaces/IUniswapV2Pair.sol';

// Vesper
// import '../Misc_AMOs/vesper/IVPool.sol';

// ------------------------------------------------

contract FraxUnifiedFarm_ERC20 is FraxUnifiedFarmTemplate {

    /* ========== STATE VARIABLES ========== */

    // -------------------- VARIES --------------------

    // Convex stkcvxFPIFRAX
    IConvexStakingWrapperFrax public stakingToken;
    I2pool public curvePool;

    // G-UNI
    // IGUniPool public stakingToken;
    
    // mStable
    // IFeederPool public stakingToken;

    // sdETH-FraxPut Vault
    // IOpynPerpVault public stakingToken;

    // StakeDAO Vault
    // IStakeDaoVault public stakingToken;

    // Uniswap V2
    // IUniswapV2Pair public stakingToken;

    // Vesper
    // IVPool public stakingToken;

    // ------------------------------------------------

    // Stake tracking
    mapping(address => LockedStake[]) public lockedStakes;

    /* ========== STRUCTS ========== */

    // Struct for the stake
    struct LockedStake {
        bytes32 kek_id;
        uint256 start_timestamp;
        uint256 liquidity;
        uint256 ending_timestamp;
        uint256 lock_multiplier; // 6 decimals of precision. 1x = 1000000
    }
    
    /* ========== CONSTRUCTOR ========== */

    constructor (
        address _owner,
        address[] memory _rewardTokens,
        address[] memory _rewardManagers,
        uint256[] memory _rewardRatesManual,
        address[] memory _gaugeControllers,
        address[] memory _rewardDistributors,
        address _stakingToken
    ) 
    FraxUnifiedFarmTemplate(_owner, _rewardTokens, _rewardManagers, _rewardRatesManual, _gaugeControllers, _rewardDistributors)
    {

        // -------------------- VARIES --------------------
        // Convex stkcvxFPIFRAX
        stakingToken = IConvexStakingWrapperFrax(_stakingToken);
        curvePool = I2pool(0xf861483fa7E511fbc37487D91B6FAa803aF5d37c);

        // G-UNI
        // stakingToken = IGUniPool(_stakingToken);
        // address token0 = address(stakingToken.token0());
        // frax_is_token0 = token0 == frax_address;

        // mStable
        // stakingToken = IFeederPool(_stakingToken);

        // StakeDAO sdETH-FraxPut Vault
        // stakingToken = IOpynPerpVault(_stakingToken);

        // StakeDAO Vault
        // stakingToken = IStakeDaoVault(_stakingToken);

        // Uniswap V2
        // stakingToken = IUniswapV2Pair(_stakingToken);
        // address token0 = stakingToken.token0();
        // if (token0 == frax_address) frax_is_token0 = true;
        // else frax_is_token0 = false;

        // Vesper
        // stakingToken = IVPool(_stakingToken);
    }

    /* ============= VIEWS ============= */

    // ------ FRAX RELATED ------

    function fraxPerLPToken() public view override returns (uint256) {
        // Get the amount of FRAX 'inside' of the lp tokens
        uint256 frax_per_lp_token;

        // Convex stkcvxFPIFRAX
        // ============================================
        {
            frax_per_lp_token = curvePool.get_virtual_price();
        }

        // G-UNI
        // ============================================
        // {
        //     (uint256 reserve0, uint256 reserve1) = stakingToken.getUnderlyingBalances();
        //     uint256 total_frax_reserves = frax_is_token0 ? reserve0 : reserve1;

        //     frax_per_lp_token = (total_frax_reserves * 1e18) / stakingToken.totalSupply();
        // }

        // mStable
        // ============================================
        // {
        //     uint256 total_frax_reserves;
        //     (, IFeederPool.BassetData memory vaultData) = (stakingToken.getBasset(frax_address));
        //     total_frax_reserves = uint256(vaultData.vaultBalance);
        //     frax_per_lp_token = (total_frax_reserves * 1e18) / stakingToken.totalSupply();
        // }

        // StakeDAO sdETH-FraxPut Vault
        // ============================================
        // {
        //    uint256 frax3crv_held = stakingToken.totalUnderlyingControlled();
        
        //    // Optimistically assume 50/50 FRAX/3CRV ratio in the metapool to save gas
        //    frax_per_lp_token = ((frax3crv_held * 1e18) / stakingToken.totalSupply()) / 2;
        // }

        // StakeDAO Vault
        // ============================================
        // {
        //    uint256 frax3crv_held = stakingToken.balance();
        
        //    // Optimistically assume 50/50 FRAX/3CRV ratio in the metapool to save gas
        //    frax_per_lp_token = ((frax3crv_held * 1e18) / stakingToken.totalSupply()) / 2;
        // }

        // Uniswap V2
        // ============================================
        // {
        //     uint256 total_frax_reserves;
        //     (uint256 reserve0, uint256 reserve1, ) = (stakingToken.getReserves());
        //     if (frax_is_token0) total_frax_reserves = reserve0;
        //     else total_frax_reserves = reserve1;

        //     frax_per_lp_token = (total_frax_reserves * 1e18) / stakingToken.totalSupply();
        // }

        // Vesper
        // ============================================
        // frax_per_lp_token = stakingToken.pricePerShare();

        return frax_per_lp_token;
    }

    // ------ LIQUIDITY AND WEIGHTS ------

    // Calculate the combined weight for an account
    function calcCurCombinedWeight(address account) public override view
        returns (
            uint256 old_combined_weight,
            uint256 new_vefxs_multiplier,
            uint256 new_combined_weight
        )
    {
        // Get the old combined weight
        old_combined_weight = _combined_weights[account];

        // Get the veFXS multipliers
        // For the calculations, use the midpoint (analogous to midpoint Riemann sum)
        new_vefxs_multiplier = veFXSMultiplier(account);

        uint256 midpoint_vefxs_multiplier;
        if (_locked_liquidity[account] == 0 && _combined_weights[account] == 0) {
            // This is only called for the first stake to make sure the veFXS multiplier is not cut in half
            midpoint_vefxs_multiplier = new_vefxs_multiplier;
        }
        else {
            midpoint_vefxs_multiplier = (new_vefxs_multiplier + _vefxsMultiplierStored[account]) / 2;
        }

        // Loop through the locked stakes, first by getting the liquidity * lock_multiplier portion
        new_combined_weight = 0;
        for (uint256 i = 0; i < lockedStakes[account].length; i++) {
            LockedStake memory thisStake = lockedStakes[account][i];
            uint256 lock_multiplier = thisStake.lock_multiplier;

            // If the lock is expired
            if (thisStake.ending_timestamp <= block.timestamp) {
                // If the lock expired in the time since the last claim, the weight needs to be proportionately averaged this time
                if (lastRewardClaimTime[account] < thisStake.ending_timestamp){
                    uint256 time_before_expiry = thisStake.ending_timestamp - lastRewardClaimTime[account];
                    uint256 time_after_expiry = block.timestamp - thisStake.ending_timestamp;

                    // Get the weighted-average lock_multiplier
                    uint256 numerator = (lock_multiplier * time_before_expiry) + (MULTIPLIER_PRECISION * time_after_expiry);
                    lock_multiplier = numerator / (time_before_expiry + time_after_expiry);
                }
                // Otherwise, it needs to just be 1x
                else {
                    lock_multiplier = MULTIPLIER_PRECISION;
                }
            }

            uint256 liquidity = thisStake.liquidity;
            uint256 combined_boosted_amount = (liquidity * (lock_multiplier + midpoint_vefxs_multiplier)) / MULTIPLIER_PRECISION;
            new_combined_weight = new_combined_weight + combined_boosted_amount;
        }
    }

    // ------ LOCK RELATED ------

    // All the locked stakes for a given account
    function lockedStakesOf(address account) external view returns (LockedStake[] memory) {
        return lockedStakes[account];
    }

    // Returns the length of the locked stakes for a given account
    function lockedStakesOfLength(address account) external view returns (uint256) {
        return lockedStakes[account].length;
    }

    // // All the locked stakes for a given account [old-school method]
    // function lockedStakesOfMultiArr(address account) external view returns (
    //     bytes32[] memory kek_ids,
    //     uint256[] memory start_timestamps,
    //     uint256[] memory liquidities,
    //     uint256[] memory ending_timestamps,
    //     uint256[] memory lock_multipliers
    // ) {
    //     for (uint256 i = 0; i < lockedStakes[account].length; i++){ 
    //         LockedStake memory thisStake = lockedStakes[account][i];
    //         kek_ids[i] = thisStake.kek_id;
    //         start_timestamps[i] = thisStake.start_timestamp;
    //         liquidities[i] = thisStake.liquidity;
    //         ending_timestamps[i] = thisStake.ending_timestamp;
    //         lock_multipliers[i] = thisStake.lock_multiplier;
    //     }
    // }

    /* =============== MUTATIVE FUNCTIONS =============== */

    // ------ STAKING ------

    function _getStake(address staker_address, bytes32 kek_id) internal view returns (LockedStake memory locked_stake, uint256 arr_idx) {
        for (uint256 i = 0; i < lockedStakes[staker_address].length; i++){ 
            if (kek_id == lockedStakes[staker_address][i].kek_id){
                locked_stake = lockedStakes[staker_address][i];
                arr_idx = i;
                break;
            }
        }
        require(locked_stake.kek_id == kek_id, "Stake not found");
        
    }

    // Add additional LPs to an existing locked stake
    function lockAdditional(bytes32 kek_id, uint256 addl_liq) updateRewardAndBalance(msg.sender, true) public {
        // Get the stake and its index
        (LockedStake memory thisStake, uint256 theArrayIndex) = _getStake(msg.sender, kek_id);

        // Calculate the new amount
        uint256 new_amt = thisStake.liquidity + addl_liq;

        // Checks
        require(addl_liq >= 0, "Must be positive");

        // Pull the tokens from the sender
        TransferHelper.safeTransferFrom(address(stakingToken), msg.sender, address(this), addl_liq);

        // Update the stake
        lockedStakes[msg.sender][theArrayIndex] = LockedStake(
            kek_id,
            thisStake.start_timestamp,
            new_amt,
            thisStake.ending_timestamp,
            thisStake.lock_multiplier
        );

        // Update liquidities
        _total_liquidity_locked += addl_liq;
        _locked_liquidity[msg.sender] += addl_liq;
        {
            address the_proxy = getProxyFor(msg.sender);
            if (the_proxy != address(0)) proxy_lp_balances[the_proxy] += addl_liq;
        }

        // Need to call to update the combined weights
        _updateRewardAndBalance(msg.sender, false);
    }

    // Two different stake functions are needed because of delegateCall and msg.sender issues (important for migration)
    function stakeLocked(uint256 liquidity, uint256 secs) nonReentrant external returns (bytes32) {
        return _stakeLocked(msg.sender, msg.sender, liquidity, secs, block.timestamp);
    }

    // If this were not internal, and source_address had an infinite approve, this could be exploitable
    // (pull funds from source_address and stake for an arbitrary staker_address)
    function _stakeLocked(
        address staker_address,
        address source_address,
        uint256 liquidity,
        uint256 secs,
        uint256 start_timestamp
    ) internal updateRewardAndBalance(staker_address, true) returns (bytes32) {
        require(stakingPaused == false || valid_migrators[msg.sender] == true, "Staking paused or in migration");
        require(secs >= lock_time_min, "Minimum stake time not met");
        require(secs <= lock_time_for_max_multiplier,"Trying to lock for too long");

        // Pull in the required token(s)
        // Varies per farm
        TransferHelper.safeTransferFrom(address(stakingToken), source_address, address(this), liquidity);

        // Get the lock multiplier and kek_id
        uint256 lock_multiplier = lockMultiplier(secs);
        bytes32 kek_id = keccak256(abi.encodePacked(staker_address, start_timestamp, liquidity, _locked_liquidity[staker_address]));
        
        // Create the locked stake
        lockedStakes[staker_address].push(LockedStake(
            kek_id,
            start_timestamp,
            liquidity,
            start_timestamp + secs,
            lock_multiplier
        ));

        // Update liquidities
        _total_liquidity_locked += liquidity;
        _locked_liquidity[staker_address] += liquidity;
        {
            address the_proxy = getProxyFor(staker_address);
            if (the_proxy != address(0)) proxy_lp_balances[the_proxy] += liquidity;
        }
        
        // Need to call again to make sure everything is correct
        _updateRewardAndBalance(staker_address, false);

        emit StakeLocked(staker_address, liquidity, secs, kek_id, source_address);

        return kek_id;
    }

    // ------ WITHDRAWING ------

    // Two different withdrawLocked functions are needed because of delegateCall and msg.sender issues (important for migration)
    function withdrawLocked(bytes32 kek_id, address destination_address) nonReentrant external returns (uint256) {
        require(withdrawalsPaused == false, "Withdrawals paused");
        return _withdrawLocked(msg.sender, destination_address, kek_id);
    }

    // No withdrawer == msg.sender check needed since this is only internally callable and the checks are done in the wrapper
    // functions like migrator_withdraw_locked() and withdrawLocked()
    function _withdrawLocked(
        address staker_address,
        address destination_address,
        bytes32 kek_id
    ) internal returns (uint256) {
        // Collect rewards first and then update the balances
        _getReward(staker_address, destination_address, true);

        // Get the stake and its index
        (LockedStake memory thisStake, uint256 theArrayIndex) = _getStake(staker_address, kek_id);
        require(block.timestamp >= thisStake.ending_timestamp || stakesUnlocked == true || valid_migrators[msg.sender] == true, "Stake is still locked!");
        uint256 liquidity = thisStake.liquidity;

        if (liquidity > 0) {
            // Update liquidities
            _total_liquidity_locked -= liquidity;
            _locked_liquidity[staker_address] -= liquidity;
            {
                address the_proxy = getProxyFor(staker_address);
                if (the_proxy != address(0)) proxy_lp_balances[the_proxy] -= liquidity;
            }

            // Remove the stake from the array
            delete lockedStakes[staker_address][theArrayIndex];

            // Give the tokens to the destination_address
            // Should throw if insufficient balance
            stakingToken.transfer(destination_address, liquidity);

            // Need to call again to make sure everything is correct
            _updateRewardAndBalance(staker_address, false);

            emit WithdrawLocked(staker_address, liquidity, kek_id, destination_address);
        }

        return liquidity;
    }


    function _getRewardExtraLogic(address rewardee, address destination_address) internal override {
        // Do nothing
    }

     /* ========== RESTRICTED FUNCTIONS - Curator / migrator callable ========== */

    // Migrator can stake for someone else (they won't be able to withdraw it back though, only staker_address can). 
    function migrator_stakeLocked_for(address staker_address, uint256 amount, uint256 secs, uint256 start_timestamp) external isMigrating {
        require(staker_allowed_migrators[staker_address][msg.sender] && valid_migrators[msg.sender], "Mig. invalid or unapproved");
        _stakeLocked(staker_address, msg.sender, amount, secs, start_timestamp);
    }

    // Used for migrations
    function migrator_withdraw_locked(address staker_address, bytes32 kek_id) external isMigrating {
        require(staker_allowed_migrators[staker_address][msg.sender] && valid_migrators[msg.sender], "Mig. invalid or unapproved");
        _withdrawLocked(staker_address, msg.sender, kek_id);
    }
    
    /* ========== RESTRICTED FUNCTIONS - Owner or timelock only ========== */

    // Inherited...

    /* ========== EVENTS ========== */

    event StakeLocked(address indexed user, uint256 amount, uint256 secs, bytes32 kek_id, address source_address);
    event WithdrawLocked(address indexed user, uint256 liquidity, bytes32 kek_id, address destination_address);
}


// File contracts/Staking/Variants/FraxUnifiedFarm_ERC20_Convex_stkcvxFPIFRAX.sol



contract FraxUnifiedFarm_ERC20_Convex_stkcvxFPIFRAX is FraxUnifiedFarm_ERC20 {
    constructor (
        address _owner,
        address[] memory _rewardTokens,
        address[] memory _rewardManagers,
        uint256[] memory _rewardRates,
        address[] memory _gaugeControllers,
        address[] memory _rewardDistributors,
        address _stakingToken 
    ) 
    FraxUnifiedFarm_ERC20(_owner , _rewardTokens, _rewardManagers, _rewardRates, _gaugeControllers, _rewardDistributors, _stakingToken)
    {}
}