// File: contracts/RariRefund.sol



// SPDX-License-Identifier: Apache-2.0

pragma solidity 0.7.6;
pragma abicoder v2;

import {ERC20} from '@openzeppelin/contracts/token/ERC20/ERC20.sol';
import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';

import {PreciseUnitMath} from './lib/PreciseUnitMath.sol';
import {SafeDecimalMath} from './lib/SafeDecimalMath.sol';
import {LowGasSafeMath as SafeMath} from './lib/LowGasSafeMath.sol';
import {Errors, _require, _revert} from './lib/BabylonErrors.sol';

/**
 * @title RariRefund
 * @author Babylon Finance
 *
 * Contract that refunds Rari users for the hack
 *
 */
contract RariRefund {
    using SafeERC20 for IERC20;
    using PreciseUnitMath for uint256;
    using SafeMath for uint256;
    using SafeDecimalMath for uint256;

    /* ============ Modifiers ============ */

    /* ============ Events ============ */

    event AmountClaimed(
        address _user,
        uint256 _timestamp,
        uint256 _daiAmount
    );

    /* ============ Constants ============ */

    address private constant SAFE = 0x97FcC2Ae862D03143b393e9fA73A32b563d57A6e;
    // Tokens
    IERC20 private constant DAI = IERC20(0x6B175474E89094C44Da98b954EedeAC495271d0F);

    /* ============ Immutables ============ */

    /* ============ State Variables ============ */

    mapping(address => uint256) public daiReimbursementAmount;
    mapping(address => bool) public claimed;

    uint256 public totalDai;
    bool public claimOpen;

    /* ============ Initializer ============ */

    constructor() {}

    /* ============ External Functions ============ */

    /**
     * Claims rari refund. Can only be done once per adddress
     *
     */
    function claimReimbursement() external {
        _require(claimOpen, Errors.CLAIM_OVER);
        uint256 daiAmount = daiReimbursementAmount[msg.sender];
        _require(!claimed[msg.sender] && daiAmount > 0, Errors.ALREADY_CLAIMED);
        claimed[msg.sender] = true;
        DAI.safeTransfer(msg.sender, daiAmount);
        emit AmountClaimed(msg.sender, block.timestamp, daiAmount);
    }

    /**
     * Sets the liquidation amount to split amongst all the whitelisted users.
     * @param _users Addresses of the user to reimburse
     * @param _daiAmounts Amounts of DAI to reimburse
     */
    function setUserReimbursement(
        address[] calldata _users,
        uint256[] calldata _daiAmounts
    ) external {
        require(msg.sender == SAFE ||
          (!claimOpen && msg.sender == 0x08839d766B1381014868eB0C3aa1C64db2B02326), 'Only emergency owner');
        for (uint256 i = 0; i < _users.length; i++) {
            require(!claimed[_users[i]], 'Already claimed');
            totalDai = totalDai.sub(daiReimbursementAmount[_users[i]]).add(_daiAmounts[i]);
            daiReimbursementAmount[_users[i]] = _daiAmounts[i];
        }
    }

    /**
     * Starts reimbursement process
     */
    function startRefund() external {
        require(msg.sender == SAFE, 'Only emergency owner');
        _require(
            DAI.balanceOf(address(this)) >= totalDai,
            Errors.REFUND_TOKENS_NOT_SET
        );
        claimOpen = true;
    }

    /**
     * Recover all proceeds in case of emergency
     */
    function retrieveRemaining() external {
        require(msg.sender == SAFE, 'Only emergency owner');
        DAI.safeTransfer(SAFE, DAI.balanceOf(address(this)));
    }
}

// File: @openzeppelin/contracts/token/ERC20/ERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "../../utils/Context.sol";
import "./IERC20.sol";
import "../../math/SafeMath.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 {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin 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 virtual returns (string memory) {
        return _name;
    }

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

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

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

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

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

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

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

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _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 `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 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 Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal virtual {
        _decimals = decimals_;
    }

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

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

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

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

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

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

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

// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "./IERC20.sol";
import "../../math/SafeMath.sol";
import "../../utils/Address.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/lib/PreciseUnitMath.sol



// SPDX-License-Identifier: Apache-2.0

/*
    Copyright 2020 Set Labs Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.7.6;

import {SignedSafeMath} from '@openzeppelin/contracts/math/SignedSafeMath.sol';

import {LowGasSafeMath} from './LowGasSafeMath.sol';

/**
 * @title PreciseUnitMath
 * @author Set Protocol
 *
 * Arithmetic for fixed-point numbers with 18 decimals of precision. Some functions taken from
 * dYdX's BaseMath library.
 *
 * CHANGELOG:
 * - 9/21/20: Added safePower function
 */
library PreciseUnitMath {
    using LowGasSafeMath for uint256;
    using SignedSafeMath for int256;

    // The number One in precise units.
    uint256 internal constant PRECISE_UNIT = 10**18;
    int256 internal constant PRECISE_UNIT_INT = 10**18;

    // Max unsigned integer value
    uint256 internal constant MAX_UINT_256 = type(uint256).max;
    // Max and min signed integer value
    int256 internal constant MAX_INT_256 = type(int256).max;
    int256 internal constant MIN_INT_256 = type(int256).min;

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function decimals() internal pure returns (uint256) {
        return 18;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function preciseUnit() internal pure returns (uint256) {
        return PRECISE_UNIT;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function preciseUnitInt() internal pure returns (int256) {
        return PRECISE_UNIT_INT;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function maxUint256() internal pure returns (uint256) {
        return MAX_UINT_256;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function maxInt256() internal pure returns (int256) {
        return MAX_INT_256;
    }

    /**
     * @dev Getter function since constants can't be read directly from libraries.
     */
    function minInt256() internal pure returns (int256) {
        return MIN_INT_256;
    }

    /**
     * @dev Multiplies value a by value b (result is rounded down). It's assumed that the value b is the significand
     * of a number with 18 decimals precision.
     */
    function preciseMul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a.mul(b).div(PRECISE_UNIT);
    }

    /**
     * @dev Multiplies value a by value b (result is rounded towards zero). It's assumed that the value b is the
     * significand of a number with 18 decimals precision.
     */
    function preciseMul(int256 a, int256 b) internal pure returns (int256) {
        return a.mul(b).div(PRECISE_UNIT_INT);
    }

    /**
     * @dev Multiplies value a by value b (result is rounded up). It's assumed that the value b is the significand
     * of a number with 18 decimals precision.
     */
    function preciseMulCeil(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0 || b == 0) {
            return 0;
        }
        return a.mul(b).sub(1).div(PRECISE_UNIT).add(1);
    }

    /**
     * @dev Divides value a by value b (result is rounded down).
     */
    function preciseDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        return a.mul(PRECISE_UNIT).div(b);
    }

    /**
     * @dev Divides value a by value b (result is rounded towards 0).
     */
    function preciseDiv(int256 a, int256 b) internal pure returns (int256) {
        return a.mul(PRECISE_UNIT_INT).div(b);
    }

    /**
     * @dev Divides value a by value b (result is rounded up or away from 0).
     */
    function preciseDivCeil(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0, 'Cant divide by 0');

        return a > 0 ? a.mul(PRECISE_UNIT).sub(1).div(b).add(1) : 0;
    }

    /**
     * @dev Divides value a by value b (result is rounded down - positive numbers toward 0 and negative away from 0).
     */
    function divDown(int256 a, int256 b) internal pure returns (int256) {
        require(b != 0, 'Cant divide by 0');
        require(a != MIN_INT_256 || b != -1, 'Invalid input');

        int256 result = a.div(b);
        if (a ^ b < 0 && a % b != 0) {
            result -= 1;
        }

        return result;
    }

    /**
     * @dev Multiplies value a by value b where rounding is towards the lesser number.
     * (positive values are rounded towards zero and negative values are rounded away from 0).
     */
    function conservativePreciseMul(int256 a, int256 b) internal pure returns (int256) {
        return divDown(a.mul(b), PRECISE_UNIT_INT);
    }

    /**
     * @dev Divides value a by value b where rounding is towards the lesser number.
     * (positive values are rounded towards zero and negative values are rounded away from 0).
     */
    function conservativePreciseDiv(int256 a, int256 b) internal pure returns (int256) {
        return divDown(a.mul(PRECISE_UNIT_INT), b);
    }

    /**
     * @dev Performs the power on a specified value, reverts on overflow.
     */
    function safePower(uint256 a, uint256 pow) internal pure returns (uint256) {
        require(a > 0, 'Value must be positive');

        uint256 result = 1;
        for (uint256 i = 0; i < pow; i++) {
            uint256 previousResult = result;

            // Using safemath multiplication prevents overflows
            result = previousResult.mul(a);
        }

        return result;
    }
}

// File: contracts/lib/SafeDecimalMath.sol



// SPDX-License-Identifier: Apache-2.0

pragma solidity 0.7.6;

import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';

import {LowGasSafeMath} from '../lib/LowGasSafeMath.sol';
import {UniversalERC20} from '../lib/UniversalERC20.sol';

library SafeDecimalMath {
    using LowGasSafeMath for uint256;
    using UniversalERC20 for IERC20;

    /* Number of decimal places in the representations. */
    uint8 internal constant decimals = 18;

    /* The number representing 1.0. */
    uint256 internal constant UNIT = 10**uint256(decimals);

    /**
     * @return Provides an interface to UNIT.
     */
    function unit() internal pure returns (uint256) {
        return UNIT;
    }

    /**
     * @return The result of multiplying x and y, interpreting the operands as fixed-point
     * decimals.
     *
     * @dev A unit factor is divided out after the product of x and y is evaluated,
     * so that product must be less than 2**256. As this is an integer division,
     * the internal division always rounds down. This helps save on gas. Rounding
     * is more expensive on gas.
     */
    function multiplyDecimal(uint256 x, uint256 y) internal pure returns (uint256) {
        /* Divide by UNIT to remove the extra factor introduced by the product. */
        return x.mul(y) / UNIT;
    }

    /**
     * @return The result of safely multiplying x and y, interpreting the operands
     * as fixed-point decimals of the specified precision unit.
     *
     * @dev The operands should be in the form of a the specified unit factor which will be
     * divided out after the product of x and y is evaluated, so that product must be
     * less than 2**256.
     *
     * Unlike multiplyDecimal, this function rounds the result to the nearest increment.
     * Rounding is useful when you need to retain fidelity for small decimal numbers
     * (eg. small fractions or percentages).
     */
    function _multiplyDecimalRound(
        uint256 x,
        uint256 y,
        uint256 precisionUnit
    ) private pure returns (uint256) {
        /* Divide by UNIT to remove the extra factor introduced by the product. */
        uint256 quotientTimesTen = x.mul(y) / (precisionUnit / 10);

        if (quotientTimesTen % 10 >= 5) {
            quotientTimesTen += 10;
        }

        return quotientTimesTen / 10;
    }

    /**
     * @return The result of safely multiplying x and y, interpreting the operands
     * as fixed-point decimals of a standard unit.
     *
     * @dev The operands should be in the standard unit factor which will be
     * divided out after the product of x and y is evaluated, so that product must be
     * less than 2**256.
     *
     * Unlike multiplyDecimal, this function rounds the result to the nearest increment.
     * Rounding is useful when you need to retain fidelity for small decimal numbers
     * (eg. small fractions or percentages).
     */
    function multiplyDecimalRound(uint256 x, uint256 y) internal pure returns (uint256) {
        return _multiplyDecimalRound(x, y, UNIT);
    }

    /**
     * @return The result of safely dividing x and y. The return value is a high
     * precision decimal.
     *
     * @dev y is divided after the product of x and the standard precision unit
     * is evaluated, so the product of x and UNIT must be less than 2**256. As
     * this is an integer division, the result is always rounded down.
     * This helps save on gas. Rounding is more expensive on gas.
     */
    function divideDecimal(uint256 x, uint256 y) internal pure returns (uint256) {
        /* Reintroduce the UNIT factor that will be divided out by y. */
        return x.mul(UNIT).div(y);
    }

    /**
     * @return The result of safely dividing x and y. The return value is as a rounded
     * decimal in the precision unit specified in the parameter.
     *
     * @dev y is divided after the product of x and the specified precision unit
     * is evaluated, so the product of x and the specified precision unit must
     * be less than 2**256. The result is rounded to the nearest increment.
     */
    function _divideDecimalRound(
        uint256 x,
        uint256 y,
        uint256 precisionUnit
    ) private pure returns (uint256) {
        uint256 resultTimesTen = x.mul(precisionUnit * 10).div(y);

        if (resultTimesTen % 10 >= 5) {
            resultTimesTen += 10;
        }

        return resultTimesTen / 10;
    }

    /**
     * @return The result of safely dividing x and y. The return value is as a rounded
     * standard precision decimal.
     *
     * @dev y is divided after the product of x and the standard precision unit
     * is evaluated, so the product of x and the standard precision unit must
     * be less than 2**256. The result is rounded to the nearest increment.
     */
    function divideDecimalRound(uint256 x, uint256 y) internal pure returns (uint256) {
        return _divideDecimalRound(x, y, UNIT);
    }

    /**
     * Normalizing amount decimals between tokens
     * @param _from       ERC20 asset address
     * @param _to     ERC20 asset address
     * @param _amount Value _to normalize (e.g. capital)
     */
    function normalizeAmountTokens(
        address _from,
        address _to,
        uint256 _amount
    ) internal view returns (uint256) {
        uint256 fromDecimals = IERC20(_from).universalDecimals();
        uint256 toDecimals = IERC20(_to).universalDecimals();

        if (fromDecimals == toDecimals) {
            return _amount;
        }
        if (toDecimals > fromDecimals) {
            return _amount.mul(10**(toDecimals - (fromDecimals)));
        }
        return _amount.div(10**(fromDecimals - (toDecimals)));
    }
}

// File: contracts/lib/LowGasSafeMath.sol



// SPDX-License-Identifier: GPL-2.0-or-later

pragma solidity 0.7.6;

/// @title Optimized overflow and underflow safe math operations
/// @notice Contains methods for doing math operations that revert on overflow or underflow for minimal gas cost
library LowGasSafeMath {
    /// @notice Returns x + y, reverts if sum overflows uint256
    /// @param x The augend
    /// @param y The addend
    /// @return z The sum of x and y
    function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x + y) >= x);
    }

    /// @notice Returns x - y, reverts if underflows
    /// @param x The minuend
    /// @param y The subtrahend
    /// @return z The difference of x and y
    function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x - y) <= x);
    }

    /// @notice Returns x * y, reverts if overflows
    /// @param x The multiplicand
    /// @param y The multiplier
    /// @return z The product of x and y
    function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require(x == 0 || (z = x * y) / x == y);
    }

    /// @notice Returns x + y, reverts if overflows or underflows
    /// @param x The augend
    /// @param y The addend
    /// @return z The sum of x and y
    function add(int256 x, int256 y) internal pure returns (int256 z) {
        require((z = x + y) >= x == (y >= 0));
    }

    /// @notice Returns x - y, reverts if overflows or underflows
    /// @param x The minuend
    /// @param y The subtrahend
    /// @return z The difference of x and y
    function sub(int256 x, int256 y) internal pure returns (int256 z) {
        require((z = x - y) <= x == (y >= 0));
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, 'SafeMath: division by zero');
        return a / b;
    }
}

// File: contracts/lib/BabylonErrors.sol



// SPDX-License-Identifier: Apache-2.0

/*
    Original version by Synthetix.io
    https://docs.synthetix.io/contracts/source/libraries/safedecimalmath

    Adapted by Babylon Finance.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at
    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

    SPDX-License-Identifier: Apache License, Version 2.0
*/

pragma solidity 0.7.6;

// solhint-disable

/**
 * @notice Forked from https://github.com/balancer-labs/balancer-core-v2/blob/master/contracts/lib/helpers/BalancerErrors.sol
 * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
 * supported.
 */
function _require(bool condition, uint256 errorCode) pure {
    if (!condition) _revert(errorCode);
}

/**
 * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
 */
function _revert(uint256 errorCode) pure {
    // We're going to dynamically create a revert string based on the error code, with the following format:
    // 'BAB#{errorCode}'
    // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
    //
    // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
    // number (8 to 16 bits) than the individual string characters.
    //
    // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
    // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
    // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
    assembly {
        // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
        // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
        // the '0' character.

        let units := add(mod(errorCode, 10), 0x30)

        errorCode := div(errorCode, 10)
        let tenths := add(mod(errorCode, 10), 0x30)

        errorCode := div(errorCode, 10)
        let hundreds := add(mod(errorCode, 10), 0x30)

        // With the individual characters, we can now construct the full string. The "BAB#" part is a known constant
        // (0x42414223): we simply shift this by 24 (to provide space for the 3 bytes of the error code), and add the
        // characters to it, each shifted by a multiple of 8.
        // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
        // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
        // array).

        let revertReason := shl(200, add(0x42414223000000, add(add(units, shl(8, tenths)), shl(16, hundreds))))

        // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
        // message will have the following layout:
        // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]

        // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
        // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
        mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
        // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
        mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
        // The string length is fixed: 7 characters.
        mstore(0x24, 7)
        // Finally, the string itself is stored.
        mstore(0x44, revertReason)

        // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
        // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
        revert(0, 100)
    }
}

library Errors {
    // Max deposit limit needs to be under the limit
    uint256 internal constant MAX_DEPOSIT_LIMIT = 0;
    // Creator needs to deposit
    uint256 internal constant MIN_CONTRIBUTION = 1;
    // Min Garden token supply >= 0
    uint256 internal constant MIN_TOKEN_SUPPLY = 2;
    // Deposit hardlock needs to be at least 1 block
    uint256 internal constant DEPOSIT_HARDLOCK = 3;
    // Needs to be at least the minimum
    uint256 internal constant MIN_LIQUIDITY = 4;
    // _reserveAssetQuantity is not equal to msg.value
    uint256 internal constant MSG_VALUE_DO_NOT_MATCH = 5;
    // Withdrawal amount has to be equal or less than msg.sender balance
    uint256 internal constant MSG_SENDER_TOKENS_DO_NOT_MATCH = 6;
    // Tokens are staked
    uint256 internal constant TOKENS_STAKED = 7;
    // Balance too low
    uint256 internal constant BALANCE_TOO_LOW = 8;
    // msg.sender doesn't have enough tokens
    uint256 internal constant MSG_SENDER_TOKENS_TOO_LOW = 9;
    //  There is an open redemption window already
    uint256 internal constant REDEMPTION_OPENED_ALREADY = 10;
    // Cannot request twice in the same window
    uint256 internal constant ALREADY_REQUESTED = 11;
    // Rewards and profits already claimed
    uint256 internal constant ALREADY_CLAIMED = 12;
    // Value have to be greater than zero
    uint256 internal constant GREATER_THAN_ZERO = 13;
    // Must be reserve asset
    uint256 internal constant MUST_BE_RESERVE_ASSET = 14;
    // Only contributors allowed
    uint256 internal constant ONLY_CONTRIBUTOR = 15;
    // Only controller allowed
    uint256 internal constant ONLY_CONTROLLER = 16;
    // Only creator allowed
    uint256 internal constant ONLY_CREATOR = 17;
    // Only keeper allowed
    uint256 internal constant ONLY_KEEPER = 18;
    // Fee is too high
    uint256 internal constant FEE_TOO_HIGH = 19;
    // Only strategy allowed
    uint256 internal constant ONLY_STRATEGY = 20;
    // Only active allowed
    uint256 internal constant ONLY_ACTIVE = 21;
    // Only inactive allowed
    uint256 internal constant ONLY_INACTIVE = 22;
    // Address should be not zero address
    uint256 internal constant ADDRESS_IS_ZERO = 23;
    // Not within range
    uint256 internal constant NOT_IN_RANGE = 24;
    // Value is too low
    uint256 internal constant VALUE_TOO_LOW = 25;
    // Value is too high
    uint256 internal constant VALUE_TOO_HIGH = 26;
    // Only strategy or protocol allowed
    uint256 internal constant ONLY_STRATEGY_OR_CONTROLLER = 27;
    // Normal withdraw possible
    uint256 internal constant NORMAL_WITHDRAWAL_POSSIBLE = 28;
    // User does not have permissions to join garden
    uint256 internal constant USER_CANNOT_JOIN = 29;
    // User does not have permissions to add strategies in garden
    uint256 internal constant USER_CANNOT_ADD_STRATEGIES = 30;
    // Only Protocol or garden
    uint256 internal constant ONLY_PROTOCOL_OR_GARDEN = 31;
    // Only Strategist
    uint256 internal constant ONLY_STRATEGIST = 32;
    // Only Integration
    uint256 internal constant ONLY_INTEGRATION = 33;
    // Only garden and data not set
    uint256 internal constant ONLY_GARDEN_AND_DATA_NOT_SET = 34;
    // Only active garden
    uint256 internal constant ONLY_ACTIVE_GARDEN = 35;
    // Contract is not a garden
    uint256 internal constant NOT_A_GARDEN = 36;
    // Not enough tokens
    uint256 internal constant STRATEGIST_TOKENS_TOO_LOW = 37;
    // Stake is too low
    uint256 internal constant STAKE_HAS_TO_AT_LEAST_ONE = 38;
    // Duration must be in range
    uint256 internal constant DURATION_MUST_BE_IN_RANGE = 39;
    // Duplicated strategies
    uint256 internal constant DUPLICATED_STRATEGIES = 40;
    // Max Capital Requested
    uint256 internal constant MAX_CAPITAL_REQUESTED = 41;
    // Votes are already resolved
    uint256 internal constant VOTES_ALREADY_RESOLVED = 42;
    // Voting window is closed
    uint256 internal constant VOTING_WINDOW_IS_OVER = 43;
    // Strategy needs to be active
    uint256 internal constant STRATEGY_NEEDS_TO_BE_ACTIVE = 44;
    // Max capital reached
    uint256 internal constant MAX_CAPITAL_REACHED = 45;
    // Capital is less then rebalance
    uint256 internal constant CAPITAL_IS_LESS_THAN_REBALANCE = 46;
    // Strategy is in cooldown period
    uint256 internal constant STRATEGY_IN_COOLDOWN = 47;
    // Strategy is not executed
    uint256 internal constant STRATEGY_IS_NOT_EXECUTED = 48;
    // Strategy is not over yet
    uint256 internal constant STRATEGY_IS_NOT_OVER_YET = 49;
    // Strategy is already finalized
    uint256 internal constant STRATEGY_IS_ALREADY_FINALIZED = 50;
    // No capital to unwind
    uint256 internal constant STRATEGY_NO_CAPITAL_TO_UNWIND = 51;
    // Strategy needs to be inactive
    uint256 internal constant STRATEGY_NEEDS_TO_BE_INACTIVE = 52;
    // Duration needs to be less
    uint256 internal constant DURATION_NEEDS_TO_BE_LESS = 53;
    // Can't sweep reserve asset
    uint256 internal constant CANNOT_SWEEP_RESERVE_ASSET = 54;
    // Voting window is opened
    uint256 internal constant VOTING_WINDOW_IS_OPENED = 55;
    // Strategy is executed
    uint256 internal constant STRATEGY_IS_EXECUTED = 56;
    // Min Rebalance Capital
    uint256 internal constant MIN_REBALANCE_CAPITAL = 57;
    // Not a valid strategy NFT
    uint256 internal constant NOT_STRATEGY_NFT = 58;
    // Garden Transfers Disabled
    uint256 internal constant GARDEN_TRANSFERS_DISABLED = 59;
    // Tokens are hardlocked
    uint256 internal constant TOKENS_HARDLOCKED = 60;
    // Max contributors reached
    uint256 internal constant MAX_CONTRIBUTORS = 61;
    // BABL Transfers Disabled
    uint256 internal constant BABL_TRANSFERS_DISABLED = 62;
    // Strategy duration range error
    uint256 internal constant DURATION_RANGE = 63;
    // Checks the min amount of voters
    uint256 internal constant MIN_VOTERS_CHECK = 64;
    // Ge contributor power error
    uint256 internal constant CONTRIBUTOR_POWER_CHECK_WINDOW = 65;
    // Not enough reserve set aside
    uint256 internal constant NOT_ENOUGH_RESERVE = 66;
    // Garden is already public
    uint256 internal constant GARDEN_ALREADY_PUBLIC = 67;
    // Withdrawal with penalty
    uint256 internal constant WITHDRAWAL_WITH_PENALTY = 68;
    // Withdrawal with penalty
    uint256 internal constant ONLY_MINING_ACTIVE = 69;
    // Overflow in supply
    uint256 internal constant OVERFLOW_IN_SUPPLY = 70;
    // Overflow in power
    uint256 internal constant OVERFLOW_IN_POWER = 71;
    // Not a system contract
    uint256 internal constant NOT_A_SYSTEM_CONTRACT = 72;
    // Strategy vs Garden mismatch
    uint256 internal constant STRATEGY_GARDEN_MISMATCH = 73;
    // Minimum quarters is 1
    uint256 internal constant QUARTERS_MIN_1 = 74;
    // Too many strategy operations
    uint256 internal constant TOO_MANY_OPS = 75;
    // Only operations
    uint256 internal constant ONLY_OPERATION = 76;
    // Strat params wrong length
    uint256 internal constant STRAT_PARAMS_LENGTH = 77;
    // Garden params wrong length
    uint256 internal constant GARDEN_PARAMS_LENGTH = 78;
    // Token names too long
    uint256 internal constant NAME_TOO_LONG = 79;
    // Contributor power overflows over garden power
    uint256 internal constant CONTRIBUTOR_POWER_OVERFLOW = 80;
    // Contributor power window out of bounds
    uint256 internal constant CONTRIBUTOR_POWER_CHECK_DEPOSITS = 81;
    // Contributor power window out of bounds
    uint256 internal constant NO_REWARDS_TO_CLAIM = 82;
    // Pause guardian paused this operation
    uint256 internal constant ONLY_UNPAUSED = 83;
    // Reentrant intent
    uint256 internal constant REENTRANT_CALL = 84;
    // Reserve asset not supported
    uint256 internal constant RESERVE_ASSET_NOT_SUPPORTED = 85;
    // Withdrawal/Deposit check min amount received
    uint256 internal constant RECEIVE_MIN_AMOUNT = 86;
    // Total Votes has to be positive
    uint256 internal constant TOTAL_VOTES_HAVE_TO_BE_POSITIVE = 87;
    // Signer has to be valid
    uint256 internal constant INVALID_SIGNER = 88;
    // Nonce has to be valid
    uint256 internal constant INVALID_NONCE = 89;
    // Garden is not public
    uint256 internal constant GARDEN_IS_NOT_PUBLIC = 90;
    // Setting max contributors
    uint256 internal constant MAX_CONTRIBUTORS_SET = 91;
    // Profit sharing mismatch for customized gardens
    uint256 internal constant PROFIT_SHARING_MISMATCH = 92;
    // Max allocation percentage
    uint256 internal constant MAX_STRATEGY_ALLOCATION_PERCENTAGE = 93;
    // new creator must not exist
    uint256 internal constant NEW_CREATOR_MUST_NOT_EXIST = 94;
    // only first creator can add
    uint256 internal constant ONLY_FIRST_CREATOR_CAN_ADD = 95;
    // invalid address
    uint256 internal constant INVALID_ADDRESS = 96;
    // creator can only renounce in some circumstances
    uint256 internal constant CREATOR_CANNOT_RENOUNCE = 97;
    // no price for trade
    uint256 internal constant NO_PRICE_FOR_TRADE = 98;
    // Max capital requested
    uint256 internal constant ZERO_CAPITAL_REQUESTED = 99;
    // Unwind capital above the limit
    uint256 internal constant INVALID_CAPITAL_TO_UNWIND = 100;
    // Mining % sharing does not match
    uint256 internal constant INVALID_MINING_VALUES = 101;
    // Max trade slippage percentage
    uint256 internal constant MAX_TRADE_SLIPPAGE_PERCENTAGE = 102;
    // Max gas fee percentage
    uint256 internal constant MAX_GAS_FEE_PERCENTAGE = 103;
    // Mismatch between voters and votes
    uint256 internal constant INVALID_VOTES_LENGTH = 104;
    // Only Rewards Distributor
    uint256 internal constant ONLY_RD = 105;
    // Fee is too LOW
    uint256 internal constant FEE_TOO_LOW = 106;
    // Only governance or emergency
    uint256 internal constant ONLY_GOVERNANCE_OR_EMERGENCY = 107;
    // Strategy invalid reserve asset amount
    uint256 internal constant INVALID_RESERVE_AMOUNT = 108;
    // Heart only pumps once a week
    uint256 internal constant HEART_ALREADY_PUMPED = 109;
    // Heart needs garden votes to pump
    uint256 internal constant HEART_VOTES_MISSING = 110;
    // Not enough fees for heart
    uint256 internal constant HEART_MINIMUM_FEES = 111;
    // Invalid heart votes length
    uint256 internal constant HEART_VOTES_LENGTH = 112;
    // Heart LP tokens not received
    uint256 internal constant HEART_LP_TOKENS = 113;
    // Heart invalid asset to lend
    uint256 internal constant HEART_ASSET_LEND_INVALID = 114;
    // Heart garden not set
    uint256 internal constant HEART_GARDEN_NOT_SET = 115;
    // Heart asset to lend is the same
    uint256 internal constant HEART_ASSET_LEND_SAME = 116;
    // Heart invalid ctoken
    uint256 internal constant HEART_INVALID_CTOKEN = 117;
    // Price per share is wrong
    uint256 internal constant PRICE_PER_SHARE_WRONG = 118;
    // Heart asset to purchase is same
    uint256 internal constant HEART_ASSET_PURCHASE_INVALID = 119;
    // Reset hardlock bigger than timestamp
    uint256 internal constant RESET_HARDLOCK_INVALID = 120;
    // Invalid referrer
    uint256 internal constant INVALID_REFERRER = 121;
    // Only Heart Garden
    uint256 internal constant ONLY_HEART_GARDEN = 122;
    // Max BABL Cap to claim by sig
    uint256 internal constant MAX_BABL_CAP_REACHED = 123;
    // Not enough BABL
    uint256 internal constant NOT_ENOUGH_BABL = 124;
    // Claim garden NFT
    uint256 internal constant CLAIM_GARDEN_NFT = 125;
    // Not enough collateral
    uint256 internal constant NOT_ENOUGH_COLLATERAL = 126;
    // Amount too low
    uint256 internal constant AMOUNT_TOO_LOW = 127;
    // Amount too high
    uint256 internal constant AMOUNT_TOO_HIGH = 128;
    // Not enough to repay debt
    uint256 internal constant SLIPPAGE_TOO_HIH = 129;
    // Invalid amount
    uint256 internal constant INVALID_AMOUNT = 130;
    // Not enough BABL
    uint256 internal constant NOT_ENOUGH_AMOUNT = 131;
    // Error minting
    uint256 internal constant MINT_ERROR = 132;
    // Error no unlock signal needed
    uint256 internal constant NO_SIGNAL_NEEDED = 133;
    // Error setting garden user lock
    uint256 internal constant SET_GARDEN_USER_LOCK = 134;
    // Error setting garden user lock
    uint256 internal constant RARI_HACK_STRAT = 135;
    // Error setting whitelist
    uint256 internal constant ALREADY_WHITELISTED = 136;
    // Error whitelist over
    uint256 internal constant WHITELIST_OVER = 137;
    // Error claim period not started or over
    uint256 internal constant CLAIM_OVER = 138;
    // Error users not whitelisted
    uint256 internal constant NOT_WHITELISTED = 139;
    // Error users has no balance to be whitelisted
    uint256 internal constant NO_BALANCE_WHITELIST = 140;
    // Error liquidation amount not set
    uint256 internal constant LIQUIDATION_AMOUNT_NOT_SET = 141;
    // Error claim  not over
    uint256 internal constant CLAIM_NOT_OVER = 142;
    // Error refund tokens not set
    uint256 internal constant REFUND_TOKENS_NOT_SET = 143;
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

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

// File: @openzeppelin/contracts/math/SafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

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

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.2 <0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

// File: @openzeppelin/contracts/math/SignedSafeMath.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @title SignedSafeMath
 * @dev Signed math operations with safety checks that revert on error.
 */
library SignedSafeMath {
    int256 constant private _INT256_MIN = -2**255;

    /**
     * @dev Returns the multiplication of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(int256 a, int256 b) internal pure returns (int256) {
        // 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;
        }

        require(!(a == -1 && b == _INT256_MIN), "SignedSafeMath: multiplication overflow");

        int256 c = a * b;
        require(c / a == b, "SignedSafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two signed 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(int256 a, int256 b) internal pure returns (int256) {
        require(b != 0, "SignedSafeMath: division by zero");
        require(!(b == -1 && a == _INT256_MIN), "SignedSafeMath: division overflow");

        int256 c = a / b;

        return c;
    }

    /**
     * @dev Returns the subtraction of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a - b;
        require((b >= 0 && c <= a) || (b < 0 && c > a), "SignedSafeMath: subtraction overflow");

        return c;
    }

    /**
     * @dev Returns the addition of two signed integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        require((b >= 0 && c >= a) || (b < 0 && c < a), "SignedSafeMath: addition overflow");

        return c;
    }
}

// File: contracts/lib/UniversalERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.7.6;

import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';

library UniversalERC20 {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    IERC20 private constant ZERO_ADDRESS = IERC20(0x0000000000000000000000000000000000000000);
    IERC20 private constant ETH_ADDRESS = IERC20(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);

    function universalTransfer(
        IERC20 token,
        address to,
        uint256 amount
    ) internal returns (bool) {
        if (amount == 0) {
            return true;
        }

        if (isETH(token)) {
            address(uint160(to)).transfer(amount);
            return true;
        } else {
            token.safeTransfer(to, amount);
            return true;
        }
    }

    function universalTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        if (amount == 0) {
            return;
        }

        if (isETH(token)) {
            require(from == msg.sender && msg.value >= amount, 'msg.value is zero');
            if (to != address(this)) {
                address(uint160(to)).transfer(amount);
            }
            if (msg.value > amount) {
                msg.sender.transfer(msg.value.sub(amount));
            }
        } else {
            token.safeTransferFrom(from, to, amount);
        }
    }

    function universalApprove(
        IERC20 token,
        address to,
        uint256 amount
    ) internal {
        if (!isETH(token)) {
            if (amount > 0 && token.allowance(address(this), to) > 0) {
                token.safeApprove(to, 0);
            }
            token.safeApprove(to, amount);
        }
    }

    function universalBalanceOf(IERC20 token, address who) internal view returns (uint256) {
        if (isETH(token)) {
            return who.balance;
        } else {
            return token.balanceOf(who);
        }
    }

    function universalDecimals(IERC20 token) internal view returns (uint256) {
        if (isETH(token)) {
            return 18;
        }

        (bool success, bytes memory data) = address(token).staticcall(abi.encodeWithSignature('decimals()'));

        return success ? abi.decode(data, (uint256)) : 18;
    }

    function isETH(IERC20 token) internal pure returns (bool) {
        return address(token) == address(ZERO_ADDRESS) || address(token) == address(ETH_ADDRESS);
    }
}