// Dependency file: @openzeppelin/contracts/utils/math/SafeMath.sol

// SPDX-License-Identifier: MIT

// pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
 * now has built in overflow checking.
 */
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) {
        unchecked {
            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) {
        unchecked {
            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) {
        unchecked {
            // 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) {
        unchecked {
            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) {
        unchecked {
            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) {
        return a + b;
    }

    /**
     * @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 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) {
        return a * b;
    }

    /**
     * @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.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        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) {
        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) {
        unchecked {
            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.
     *
     * 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) {
        unchecked {
            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) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}


// Dependency file: @openzeppelin/contracts/proxy/Clones.sol


// pragma solidity ^0.8.0;

/**
 * @dev https://eips.ethereum.org/EIPS/eip-1167[EIP 1167] is a standard for
 * deploying minimal proxy contracts, also known as "clones".
 *
 * > To simply and cheaply clone contract functionality in an immutable way, this standard specifies
 * > a minimal bytecode implementation that delegates all calls to a known, fixed address.
 *
 * The library includes functions to deploy a proxy using either `create` (traditional deployment) or `create2`
 * (salted deterministic deployment). It also includes functions to predict the addresses of clones deployed using the
 * deterministic method.
 *
 * _Available since v3.4._
 */
library Clones {
    /**
     * @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
     *
     * This function uses the create opcode, which should never revert.
     */
    function clone(address implementation) internal returns (address instance) {
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
            mstore(add(ptr, 0x14), shl(0x60, implementation))
            mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000)
            instance := create(0, ptr, 0x37)
        }
        require(instance != address(0), "ERC1167: create failed");
    }

    /**
     * @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
     *
     * This function uses the create2 opcode and a `salt` to deterministically deploy
     * the clone. Using the same `implementation` and `salt` multiple time will revert, since
     * the clones cannot be deployed twice at the same address.
     */
    function cloneDeterministic(address implementation, bytes32 salt) internal returns (address instance) {
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
            mstore(add(ptr, 0x14), shl(0x60, implementation))
            mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000)
            instance := create2(0, ptr, 0x37, salt)
        }
        require(instance != address(0), "ERC1167: create2 failed");
    }

    /**
     * @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
     */
    function predictDeterministicAddress(
        address implementation,
        bytes32 salt,
        address deployer
    ) internal pure returns (address predicted) {
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
            mstore(add(ptr, 0x14), shl(0x60, implementation))
            mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf3ff00000000000000000000000000000000)
            mstore(add(ptr, 0x38), shl(0x60, deployer))
            mstore(add(ptr, 0x4c), salt)
            mstore(add(ptr, 0x6c), keccak256(ptr, 0x37))
            predicted := keccak256(add(ptr, 0x37), 0x55)
        }
    }

    /**
     * @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
     */
    function predictDeterministicAddress(address implementation, bytes32 salt)
        internal
        view
        returns (address predicted)
    {
        return predictDeterministicAddress(implementation, salt, address(this));
    }
}


// Dependency file: @openzeppelin/contracts/utils/Address.sol


// pragma solidity ^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;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}


// Dependency file: contracts/interfaces/IUniswapV2Factory.sol

// pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(
        address indexed token0,
        address indexed token1,
        address pair,
        uint256
    );

    function feeTo() external view returns (address);

    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB)
        external
        view
        returns (address pair);

    function allPairs(uint256) external view returns (address pair);

    function allPairsLength() external view returns (uint256);

    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);

    function setFeeTo(address) external;

    function setFeeToSetter(address) external;
}


// Dependency file: contracts/interfaces/IUniswapV2Router02.sol

// pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    )
        external
        returns (
            uint256 amountA,
            uint256 amountB,
            uint256 liquidity
        );

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );

    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB);

    function removeLiquidityETH(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountToken, uint256 amountETH);

    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountA, uint256 amountB);

    function removeLiquidityETHWithPermit(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountToken, uint256 amountETH);

    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapTokensForExactTokens(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactETHForTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function swapTokensForExactETH(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactTokensForETH(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapETHForExactTokens(
        uint256 amountOut,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function quote(
        uint256 amountA,
        uint256 reserveA,
        uint256 reserveB
    ) external pure returns (uint256 amountB);

    function getAmountOut(
        uint256 amountIn,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountOut);

    function getAmountIn(
        uint256 amountOut,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountIn);

    function getAmountsOut(uint256 amountIn, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);

    function getAmountsIn(uint256 amountOut, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);
}

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountETH);

    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;
}


// Dependency file: contracts/interfaces/IERC20Extended.sol

// pragma solidity =0.8.4;

interface IERC20Extended {
    function totalSupply() external view returns (uint256);

    function decimals() external view returns (uint8);

    function symbol() external view returns (string memory);

    function name() external view returns (string memory);

    function balanceOf(address account) external view returns (uint256);

    function transfer(address recipient, uint256 amount)
        external
        returns (bool);

    function allowance(address _owner, address spender)
        external
        view
        returns (uint256);

    function approve(address spender, uint256 amount) external returns (bool);

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}


// Dependency file: contracts/buyback/Auth.sol

// pragma solidity =0.8.4;

abstract contract Auth {
    address internal owner;
    mapping(address => bool) internal authorizations;

    constructor(address _owner) {
        owner = _owner;
        authorizations[_owner] = true;
    }

    /**
     * Function modifier to require caller to be contract owner
     */
    modifier onlyOwner() {
        require(isOwner(msg.sender), "!OWNER");
        _;
    }

    /**
     * Function modifier to require caller to be authorized
     */
    modifier authorized() {
        require(isAuthorized(msg.sender), "!AUTHORIZED");
        _;
    }

    /**
     * Authorize address. Owner only
     */
    function authorize(address adr) public onlyOwner {
        authorizations[adr] = true;
    }

    /**
     * Remove address' authorization. Owner only
     */
    function unauthorize(address adr) public onlyOwner {
        authorizations[adr] = false;
    }

    /**
     * Check if address is owner
     */
    function isOwner(address account) public view returns (bool) {
        return account == owner;
    }

    /**
     * Return address' authorization status
     */
    function isAuthorized(address adr) public view returns (bool) {
        return authorizations[adr];
    }

    /**
     * Transfer ownership to new address. Caller must be owner. Leaves old owner authorized
     */
    function transferOwnership(address payable adr) public onlyOwner {
        owner = adr;
        authorizations[adr] = true;
        emit OwnershipTransferred(adr);
    }

    event OwnershipTransferred(address owner);
}


// Dependency file: @openzeppelin/contracts/token/ERC20/IERC20.sol


// pragma solidity ^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);
}


// Dependency file: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol


// pragma solidity ^0.8.0;

// import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
// import "@openzeppelin/contracts/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 Address for address;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}


// Dependency file: contracts/buyback/DividendDistributor.sol

// pragma solidity =0.8.4;

// import "@openzeppelin/contracts/utils/math/SafeMath.sol";
// import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
// import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

// import "contracts/interfaces/IUniswapV2Router02.sol";
// import "contracts/interfaces/IERC20Extended.sol";

interface IDividendDistributor {
    function setDistributionCriteria(
        uint256 _minPeriod,
        uint256 _minDistribution
    ) external;

    function setShare(address shareholder, uint256 amount) external;

    function deposit() external payable;

    function process(uint256 gas) external;
}

contract DividendDistributor is IDividendDistributor {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    address public _token;

    struct Share {
        uint256 amount;
        uint256 totalExcluded;
        uint256 totalRealised;
    }

    IERC20Extended public rewardToken;
    IUniswapV2Router02 public router;

    address[] public shareholders;
    mapping(address => uint256) public shareholderIndexes;
    mapping(address => uint256) public shareholderClaims;

    mapping(address => Share) public shares;

    uint256 public totalShares;
    uint256 public totalDividends;
    uint256 public totalDistributed;
    uint256 public dividendsPerShare;
    uint256 public dividendsPerShareAccuracyFactor;

    uint256 public minPeriod;
    uint256 public minDistribution;

    uint256 currentIndex;

    bool initialized;
    modifier initializer() {
        require(!initialized);
        _;
        initialized = true;
    }

    modifier onlyToken() {
        require(msg.sender == _token);
        _;
    }

    constructor(address rewardToken_, address router_) {
        _token = msg.sender;
        rewardToken = IERC20Extended(rewardToken_);
        router = IUniswapV2Router02(router_);

        dividendsPerShareAccuracyFactor = 10**36;
        minPeriod = 1 hours;
        minDistribution = 1 * (10**rewardToken.decimals());
    }

    function setDistributionCriteria(
        uint256 _minPeriod,
        uint256 _minDistribution
    ) external override onlyToken {
        minPeriod = _minPeriod;
        minDistribution = _minDistribution;
    }

    function setShare(address shareholder, uint256 amount)
        external
        override
        onlyToken
    {
        if (shares[shareholder].amount > 0) {
            distributeDividend(shareholder);
        }

        if (amount > 0 && shares[shareholder].amount == 0) {
            addShareholder(shareholder);
        } else if (amount == 0 && shares[shareholder].amount > 0) {
            removeShareholder(shareholder);
        }

        totalShares = totalShares.sub(shares[shareholder].amount).add(amount);
        shares[shareholder].amount = amount;
        shares[shareholder].totalExcluded = getCumulativeDividends(
            shares[shareholder].amount
        );
    }

    function deposit() external payable override onlyToken {
        uint256 balanceBefore = rewardToken.balanceOf(address(this));

        address[] memory path = new address[](2);
        path[0] = router.WETH();
        path[1] = address(rewardToken);

        router.swapExactETHForTokensSupportingFeeOnTransferTokens{
            value: msg.value
        }(0, path, address(this), block.timestamp);

        uint256 amount = rewardToken.balanceOf(address(this)).sub(
            balanceBefore
        );

        totalDividends = totalDividends.add(amount);
        dividendsPerShare = dividendsPerShare.add(
            dividendsPerShareAccuracyFactor.mul(amount).div(totalShares)
        );
    }

    function process(uint256 gas) external override onlyToken {
        uint256 shareholderCount = shareholders.length;

        if (shareholderCount == 0) {
            return;
        }

        uint256 gasUsed = 0;
        uint256 gasLeft = gasleft();

        uint256 iterations = 0;

        while (gasUsed < gas && iterations < shareholderCount) {
            if (currentIndex >= shareholderCount) {
                currentIndex = 0;
            }

            if (shouldDistribute(shareholders[currentIndex])) {
                distributeDividend(shareholders[currentIndex]);
            }

            gasUsed = gasUsed.add(gasLeft.sub(gasleft()));
            gasLeft = gasleft();
            currentIndex++;
            iterations++;
        }
    }

    function shouldDistribute(address shareholder)
        internal
        view
        returns (bool)
    {
        return
            shareholderClaims[shareholder] + minPeriod < block.timestamp &&
            getUnpaidEarnings(shareholder) > minDistribution;
    }

    function distributeDividend(address shareholder) internal {
        if (shares[shareholder].amount == 0) {
            return;
        }

        uint256 amount = getUnpaidEarnings(shareholder);
        if (amount > 0) {
            totalDistributed = totalDistributed.add(amount);
            IERC20(address(rewardToken)).safeTransfer(shareholder, amount);
            shareholderClaims[shareholder] = block.timestamp;
            shares[shareholder].totalRealised = shares[shareholder]
                .totalRealised
                .add(amount);
            shares[shareholder].totalExcluded = getCumulativeDividends(
                shares[shareholder].amount
            );
        }
    }

    function claimDividend() external {
        distributeDividend(msg.sender);
    }

    function getUnpaidEarnings(address shareholder)
        public
        view
        returns (uint256)
    {
        if (shares[shareholder].amount == 0) {
            return 0;
        }

        uint256 shareholderTotalDividends = getCumulativeDividends(
            shares[shareholder].amount
        );
        uint256 shareholderTotalExcluded = shares[shareholder].totalExcluded;

        if (shareholderTotalDividends <= shareholderTotalExcluded) {
            return 0;
        }

        return shareholderTotalDividends.sub(shareholderTotalExcluded);
    }

    function getCumulativeDividends(uint256 share)
        internal
        view
        returns (uint256)
    {
        return
            share.mul(dividendsPerShare).div(dividendsPerShareAccuracyFactor);
    }

    function addShareholder(address shareholder) internal {
        shareholderIndexes[shareholder] = shareholders.length;
        shareholders.push(shareholder);
    }

    function removeShareholder(address shareholder) internal {
        shareholders[shareholderIndexes[shareholder]] = shareholders[
            shareholders.length - 1
        ];
        shareholderIndexes[
            shareholders[shareholders.length - 1]
        ] = shareholderIndexes[shareholder];
        shareholders.pop();
    }
}


// Dependency file: contracts/BaseToken.sol

// pragma solidity =0.8.4;

enum TokenType {
    standard,
    antiBotStandard,
    liquidityGenerator,
    antiBotLiquidityGenerator,
    baby,
    antiBotBaby,
    buybackBaby,
    antiBotBuybackBaby
}

abstract contract BaseToken {
    event TokenCreated(
        address indexed owner,
        address indexed token,
        TokenType tokenType,
        uint256 version
    );
}


// Root file: contracts/buyback/BuybackBabyToken.sol

pragma solidity =0.8.4;

// import "@openzeppelin/contracts/utils/math/SafeMath.sol";
// import "@openzeppelin/contracts/proxy/Clones.sol";
// import "@openzeppelin/contracts/utils/Address.sol";

// import "contracts/interfaces/IUniswapV2Factory.sol";
// import "contracts/interfaces/IUniswapV2Router02.sol";
// import "contracts/interfaces/IERC20Extended.sol";
// import "contracts/buyback/Auth.sol";
// import "contracts/buyback/DividendDistributor.sol";
// import "contracts/BaseToken.sol";

contract BuybackBabyToken is IERC20Extended, Auth, BaseToken {
    using SafeMath for uint256;
    using Address for address;
    using Address for address payable;

    uint256 public constant VERSION = 3;

    address private constant DEAD = address(0xdead);
    address private constant ZERO = address(0);
    uint8 private constant _decimals = 9;

    string private _name;
    string private _symbol;
    uint256 private _totalSupply;

    address public rewardToken;
    IUniswapV2Router02 public router;
    address public pair;
    address public marketingFeeReceiver;

    uint256 public liquidityFee; // default: 200
    uint256 public buybackFee; // default: 300
    uint256 public reflectionFee; // default: 800
    uint256 public marketingFee; // default: 100
    uint256 public totalFee;
    uint256 public feeDenominator; // default: 10000

    uint256 public targetLiquidity; // default: 25
    uint256 public targetLiquidityDenominator; // default: 100

    uint256 public buybackMultiplierNumerator; // default: 200
    uint256 public buybackMultiplierDenominator; // default: 100
    uint256 public buybackMultiplierTriggeredAt;
    uint256 public buybackMultiplierLength; // default: 30 mins

    bool public autoBuybackEnabled;

    uint256 public autoBuybackCap;
    uint256 public autoBuybackAccumulator;
    uint256 public autoBuybackAmount;
    uint256 public autoBuybackBlockPeriod;
    uint256 public autoBuybackBlockLast;

    DividendDistributor public distributor;

    uint256 public distributorGas;

    bool public swapEnabled;
    uint256 public swapThreshold;

    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;

    mapping(address => bool) public buyBacker;
    mapping(address => bool) public isFeeExempt;
    mapping(address => bool) public isDividendExempt;

    event AutoLiquify(uint256 amountBNB, uint256 amountBOG);
    event BuybackMultiplierActive(uint256 duration);

    bool inSwap;
    modifier swapping() {
        inSwap = true;
        _;
        inSwap = false;
    }

    modifier onlyBuybacker() {
        require(buyBacker[msg.sender] == true, "Not a buybacker");
        _;
    }

    constructor(
        string memory name_,
        string memory symbol_,
        uint256 totalSupply_,
        address rewardToken_,
        address router_,
        uint256[5] memory feeSettings_,
        address serviceFeeReceiver_,
        uint256 serviceFee_
    ) payable Auth(msg.sender) {
        _name = name_;
        _symbol = symbol_;
        _totalSupply = totalSupply_;

        rewardToken = rewardToken_;
        router = IUniswapV2Router02(router_);
        pair = IUniswapV2Factory(router.factory()).createPair(
            address(this),
            router.WETH()
        );
        distributor = new DividendDistributor(rewardToken_, router_);

        _initializeFees(feeSettings_);
        _initializeLiquidityBuyBack();

        distributorGas = 500_000;
        swapEnabled = true;
        swapThreshold = _totalSupply / 1000; // 0.1%

        isFeeExempt[msg.sender] = true;
        isDividendExempt[pair] = true;
        isDividendExempt[address(this)] = true;
        isDividendExempt[DEAD] = true;
        buyBacker[msg.sender] = true;

        marketingFeeReceiver = msg.sender;
        require(
            !marketingFeeReceiver.isContract(),
            "Marketing wallet cannot be a contract"
        );

        _allowances[address(this)][address(router)] = _totalSupply;
        _allowances[address(this)][address(pair)] = _totalSupply;

        _balances[msg.sender] = _totalSupply;
        emit Transfer(address(0), msg.sender, _totalSupply);

        emit TokenCreated(
            msg.sender,
            address(this),
            TokenType.buybackBaby,
            VERSION
        );

        payable(serviceFeeReceiver_).transfer(serviceFee_);
    }

    function _initializeFees(uint256[5] memory feeSettings_) internal {
        _setFees(
            feeSettings_[0], // liquidityFee
            feeSettings_[1], // buybackFee
            feeSettings_[2], // reflectionFee
            feeSettings_[3], // marketingFee
            feeSettings_[4] // feeDenominator
        );
    }

    function _initializeLiquidityBuyBack() internal {
        targetLiquidity = 25;
        targetLiquidityDenominator = 100;

        buybackMultiplierNumerator = 200;
        buybackMultiplierDenominator = 100;
        buybackMultiplierLength = 30 minutes;
    }

    receive() external payable {}

    function totalSupply() external view override returns (uint256) {
        return _totalSupply;
    }

    function decimals() external pure override returns (uint8) {
        return _decimals;
    }

    function symbol() external view override returns (string memory) {
        return _symbol;
    }

    function name() external view override returns (string memory) {
        return _name;
    }

    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    function allowance(address holder, address spender)
        external
        view
        override
        returns (uint256)
    {
        return _allowances[holder][spender];
    }

    function approve(address spender, uint256 amount)
        public
        override
        returns (bool)
    {
        _allowances[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function approveMax(address spender) external returns (bool) {
        return approve(spender, _totalSupply);
    }

    function transfer(address recipient, uint256 amount)
        external
        override
        returns (bool)
    {
        return _transferFrom(msg.sender, recipient, amount);
    }

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external override returns (bool) {
        if (_allowances[sender][msg.sender] != _totalSupply) {
            _allowances[sender][msg.sender] = _allowances[sender][msg.sender]
                .sub(amount, "Insufficient Allowance");
        }

        return _transferFrom(sender, recipient, amount);
    }

    function _transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) internal returns (bool) {
        if (inSwap) {
            return _basicTransfer(sender, recipient, amount);
        }

        if (shouldSwapBack()) {
            swapBack();
        }
        if (shouldAutoBuyback()) {
            triggerAutoBuyback();
        }

        _balances[sender] = _balances[sender].sub(
            amount,
            "Insufficient Balance"
        );

        uint256 amountReceived = shouldTakeFee(sender)
            ? takeFee(sender, recipient, amount)
            : amount;

        _balances[recipient] = _balances[recipient].add(amountReceived);

        if (!isDividendExempt[sender]) {
            try distributor.setShare(sender, _balances[sender]) {} catch {}
        }
        if (!isDividendExempt[recipient]) {
            try
                distributor.setShare(recipient, _balances[recipient])
            {} catch {}
        }

        try distributor.process(distributorGas) {} catch {}

        emit Transfer(sender, recipient, amountReceived);
        return true;
    }

    function _basicTransfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal returns (bool) {
        _balances[sender] = _balances[sender].sub(
            amount,
            "Insufficient Balance"
        );
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
        return true;
    }

    function shouldTakeFee(address sender) internal view returns (bool) {
        return !isFeeExempt[sender] && totalFee > 0;
    }

    function getTotalFee(bool selling) public view returns (uint256) {
        if (selling) {
            return getMultipliedFee();
        }
        return totalFee;
    }

    function getMultipliedFee() public view returns (uint256) {
        if (
            buybackMultiplierTriggeredAt.add(buybackMultiplierLength) >
            block.timestamp
        ) {
            uint256 remainingTime = buybackMultiplierTriggeredAt
                .add(buybackMultiplierLength)
                .sub(block.timestamp);
            uint256 feeIncrease = totalFee
                .mul(buybackMultiplierNumerator)
                .div(buybackMultiplierDenominator)
                .sub(totalFee);

            uint256 increasedFee = totalFee.add(
                feeIncrease.mul(remainingTime).div(buybackMultiplierLength)
            );
            return
                increasedFee > feeDenominator / 4
                    ? feeDenominator / 4
                    : increasedFee;
        }
        return totalFee;
    }

    function takeFee(
        address sender,
        address receiver,
        uint256 amount
    ) internal returns (uint256) {
        uint256 feeAmount = amount.mul(getTotalFee(receiver == pair)).div(
            feeDenominator
        );

        _balances[address(this)] = _balances[address(this)].add(feeAmount);
        emit Transfer(sender, address(this), feeAmount);

        return amount.sub(feeAmount);
    }

    function shouldSwapBack() internal view returns (bool) {
        return
            msg.sender != pair &&
            !inSwap &&
            swapEnabled &&
            _balances[address(this)] >= swapThreshold;
    }

    function swapBack() internal swapping {
        uint256 dynamicLiquidityFee = isOverLiquified(
            targetLiquidity,
            targetLiquidityDenominator
        )
            ? 0
            : liquidityFee;
        uint256 amountToLiquify;
        if (totalFee > 0) {
            amountToLiquify = swapThreshold
                .mul(dynamicLiquidityFee)
                .div(totalFee)
                .div(2);
        }
        uint256 amountToSwap = swapThreshold.sub(amountToLiquify);

        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = router.WETH();
        uint256 balanceBefore = address(this).balance;

        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            amountToSwap,
            0,
            path,
            address(this),
            block.timestamp
        );

        uint256 amountBNB = address(this).balance.sub(balanceBefore);

        uint256 totalBNBFee = totalFee.sub(dynamicLiquidityFee.div(2));

        uint256 amountBNBLiquidity;
        if (totalBNBFee > 0) {
            amountBNBLiquidity = amountBNB
                .mul(dynamicLiquidityFee)
                .div(totalBNBFee)
                .div(2);

            uint256 amountBNBReflection = amountBNB.mul(reflectionFee).div(
                totalBNBFee
            );
            uint256 amountBNBMarketing = amountBNB.mul(marketingFee).div(
                totalBNBFee
            );

            try distributor.deposit{ value: amountBNBReflection }() {} catch {}
            payable(marketingFeeReceiver).transfer(amountBNBMarketing);
        }

        if (amountToLiquify > 0) {
            router.addLiquidityETH{ value: amountBNBLiquidity }(
                address(this),
                amountToLiquify,
                0,
                0,
                DEAD,
                block.timestamp
            );
            emit AutoLiquify(amountBNBLiquidity, amountToLiquify);
        }
    }

    function shouldAutoBuyback() internal view returns (bool) {
        return
            msg.sender != pair &&
            !inSwap &&
            autoBuybackEnabled &&
            autoBuybackBlockLast + autoBuybackBlockPeriod <= block.number && // After N blocks from last buyback
            address(this).balance >= autoBuybackAmount;
    }

    function triggerZeusBuyback(uint256 amount, bool triggerBuybackMultiplier)
        external
        authorized
    {
        buyTokens(amount, DEAD);
        if (triggerBuybackMultiplier) {
            buybackMultiplierTriggeredAt = block.timestamp;
            emit BuybackMultiplierActive(buybackMultiplierLength);
        }
    }

    function clearBuybackMultiplier() external authorized {
        buybackMultiplierTriggeredAt = 0;
    }

    function triggerAutoBuyback() internal {
        buyTokens(autoBuybackAmount, DEAD);
        autoBuybackBlockLast = block.number;
        autoBuybackAccumulator = autoBuybackAccumulator.add(autoBuybackAmount);
        if (autoBuybackAccumulator > autoBuybackCap) {
            autoBuybackEnabled = false;
        }
    }

    function buyTokens(uint256 amount, address to) internal swapping {
        address[] memory path = new address[](2);
        path[0] = router.WETH();
        path[1] = address(this);

        router.swapExactETHForTokensSupportingFeeOnTransferTokens{
            value: amount
        }(0, path, to, block.timestamp);
    }

    function setAutoBuybackSettings(
        bool _enabled,
        uint256 _cap,
        uint256 _amount,
        uint256 _period
    ) external authorized {
        require(_period > 0, "Period must be greater than 0");
        autoBuybackEnabled = _enabled;
        autoBuybackCap = _cap;
        autoBuybackAccumulator = 0;
        autoBuybackAmount = _amount;
        autoBuybackBlockPeriod = _period;
        autoBuybackBlockLast = block.number;
    }

    function setBuybackMultiplierSettings(
        uint256 numerator,
        uint256 denominator,
        uint256 length
    ) external authorized {
        require(length <= 2 hours, "Length must be less than 2 hours");
        require(numerator / denominator <= 2 && numerator > denominator);
        buybackMultiplierNumerator = numerator;
        buybackMultiplierDenominator = denominator;
        buybackMultiplierLength = length;
    }

    function setIsDividendExempt(address holder, bool exempt)
        external
        authorized
    {
        require(holder != address(this) && holder != pair);
        isDividendExempt[holder] = exempt;
        if (exempt) {
            distributor.setShare(holder, 0);
        } else {
            distributor.setShare(holder, _balances[holder]);
        }
    }

    function setIsFeeExempt(address holder) external authorized {
        isFeeExempt[holder] = true;
    }

    function setBuyBacker(address acc, bool add) external authorized {
        buyBacker[acc] = add;
    }

    function setFees(
        uint256 _liquidityFee,
        uint256 _buybackFee,
        uint256 _reflectionFee,
        uint256 _marketingFee,
        uint256 _feeDenominator
    ) public authorized {
        _setFees(
            _liquidityFee,
            _buybackFee,
            _reflectionFee,
            _marketingFee,
            _feeDenominator
        );
    }

    function _setFees(
        uint256 _liquidityFee,
        uint256 _buybackFee,
        uint256 _reflectionFee,
        uint256 _marketingFee,
        uint256 _feeDenominator
    ) internal {
        liquidityFee = _liquidityFee;
        buybackFee = _buybackFee;
        reflectionFee = _reflectionFee;
        marketingFee = _marketingFee;
        totalFee = _liquidityFee.add(_buybackFee).add(_reflectionFee).add(
            _marketingFee
        );
        feeDenominator = _feeDenominator;
        require(
            totalFee <= feeDenominator / 4,
            "Total fee should not be greater than 1/4 of fee denominator"
        );
    }

    function setFeeReceivers(address _marketingFeeReceiver)
        external
        authorized
    {
        require(
            _marketingFeeReceiver != marketingFeeReceiver,
            "Marketing wallet is already that address"
        );
        require(
            !_marketingFeeReceiver.isContract(),
            "Marketing wallet cannot be a contract"
        );
        marketingFeeReceiver = _marketingFeeReceiver;
    }

    function setSwapBackSettings(bool _enabled, uint256 _amount)
        external
        authorized
    {
        require(
            _enabled && _amount >= _totalSupply / 100_000,
            "Swapback amount should be at least 0.001% of total supply"
        );
        swapEnabled = _enabled;
        swapThreshold = _amount;
    }

    function setTargetLiquidity(uint256 _target, uint256 _denominator)
        external
        authorized
    {
        require(_denominator > 0, "Denominator must be greater than 0");
        targetLiquidity = _target;
        targetLiquidityDenominator = _denominator;
    }

    function setDistributionCriteria(
        uint256 _minPeriod,
        uint256 _minDistribution
    ) external onlyOwner {
        distributor.setDistributionCriteria(_minPeriod, _minDistribution);
    }

    function setDistributorSettings(uint256 gas) external authorized {
        require(
            gas >= 200_000 && gas <= 500_000,
            "gasForProcessing must be between 200,000 and 500,000"
        );
        distributorGas = gas;
    }

    function getCirculatingSupply() public view returns (uint256) {
        return _totalSupply.sub(balanceOf(DEAD)).sub(balanceOf(ZERO));
    }

    function getLiquidityBacking(uint256 accuracy)
        public
        view
        returns (uint256)
    {
        return accuracy.mul(balanceOf(pair).mul(2)).div(getCirculatingSupply());
    }

    function isOverLiquified(uint256 target, uint256 accuracy)
        public
        view
        returns (bool)
    {
        return getLiquidityBacking(accuracy) > target;
    }
}