Contract Source Code:

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

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

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

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

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

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

    /**
     * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
     * `nonReentrant` function in the call stack.
     */
    function _reentrancyGuardEntered() internal view returns (bool) {
        return _status == _ENTERED;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     *
     * CAUTION: See Security Considerations above.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

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

    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../extensions/IERC20Permit.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 Address for address;

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

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

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
            _callOptionalReturn(token, approvalCall);
        }
    }

    /**
     * @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
     * Revert on invalid signature.
     */
    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

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

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return
            success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

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

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

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

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // Look for revert reason and bubble it up if present
        if (returndata.length > 0) {
            // The easiest way to bubble the revert reason is using memory via assembly
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert(errorMessage);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)

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

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)

pragma solidity ^0.8.0;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    enum Rounding {
        Down, // Toward negative infinity
        Up, // Toward infinity
        Zero // Toward zero
    }

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

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

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

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds up instead
     * of rounding down.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
     * with further edits by Uniswap Labs also under MIT license.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod0 := mul(x, y)
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                // The surrounding unchecked block does not change this fact.
                // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1, "Math: mulDiv overflow");

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
            // See https://cs.stackexchange.com/q/138556/92363.

            // Does not overflow because the denominator cannot be zero at this stage in the function.
            uint256 twos = denominator & (~denominator + 1);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
            // in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10, rounded down, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10 ** 64) {
                value /= 10 ** 64;
                result += 64;
            }
            if (value >= 10 ** 32) {
                value /= 10 ** 32;
                result += 32;
            }
            if (value >= 10 ** 16) {
                value /= 10 ** 16;
                result += 16;
            }
            if (value >= 10 ** 8) {
                value /= 10 ** 8;
                result += 8;
            }
            if (value >= 10 ** 4) {
                value /= 10 ** 4;
                result += 4;
            }
            if (value >= 10 ** 2) {
                value /= 10 ** 2;
                result += 2;
            }
            if (value >= 10 ** 1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256, rounded down, of a positive value.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/SafeMath.sol)

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 generally not needed starting with Solidity 0.8, since 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 subtraction 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;
        }
    }
}

// SPDX-License-Identifier: BUSL-1.1

/**************************************************************************************************************************************************

 /$$$$$$$$                                 /$$$$$$$$ /$$                                                  
| $$_____/                                | $$_____/|__/                                                  
| $$    /$$$$$$  /$$$$$$$   /$$$$$$       | $$       /$$ /$$$$$$$   /$$$$$$  /$$$$$$$   /$$$$$$$  /$$$$$$ 
| $$$$$|____  $$| $$__  $$ /$$__  $$      | $$$$$   | $$| $$__  $$ |____  $$| $$__  $$ /$$_____/ /$$__  $$
| $$__/ /$$$$$$$| $$  \ $$| $$  \ $$      | $$__/   | $$| $$  \ $$  /$$$$$$$| $$  \ $$| $$      | $$$$$$$$
| $$   /$$__  $$| $$  | $$| $$  | $$      | $$      | $$| $$  | $$ /$$__  $$| $$  | $$| $$      | $$_____/
| $$  |  $$$$$$$| $$  | $$|  $$$$$$$      | $$      | $$| $$  | $$|  $$$$$$$| $$  | $$|  $$$$$$$|  $$$$$$$
|__/   \_______/|__/  |__/ \____  $$      |__/      |__/|__/  |__/ \_______/|__/  |__/ \_______/ \_______/
                           /$$  \ $$                                                                      
                          |  $$$$$$/                                                                      
                           \______/                                                                       
                                                                                                                                                    
#### Website: https://fang.finance/
#### Author: kell

**************************************************************************************************************************************************/

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "../interfaces/IBasisAsset.sol";

import "../interfaces/IOracle.sol";
import "../interfaces/farming/IBlackholeGauge.sol";
import "../interfaces/farming/IBlackholeVoter.sol";

contract GFangRewardPool is ReentrancyGuard {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    // governance
    address public operator;

    // Info of each user.
    struct UserInfo {
        uint256 amount; // How many LP tokens the user has provided.
        uint256 rewardDebt; // Reward debt. See explanation below.
    }

    enum GaugeDex {
        NONE, // 0
        BLACKHOLE // 1
    }

    struct GaugeInfo {
        bool isGauge;   // If this is a gauge
        address gauge;  // The gauge
        GaugeDex gaugeDex; // The type of gauge (None or Blackhole)
    }

    // Info of each pool.
    struct PoolInfo {
        IERC20 token; // Address of LP token contract.
        uint256 depFee; // deposit fee that is applied to created pool.
        uint256 allocPoint; // How many allocation points assigned to this pool. GFANGs to distribute per block.
        uint256 lastRewardTime; // Last time that GFANGs distribution occurs.
        uint256 accGfangPerShare; // Accumulated GFANGs per share, times 1e18. See below.
        bool isStarted; // if lastRewardTime has passed
        GaugeInfo gaugeInfo; // Gauge info (does this pool have a gauge and where is it)
        uint256 poolGfangPerSec; // rewards per second for pool (acts as allocPoint)
    }

    IERC20 public gfang;
    IOracle public gfangOracle;
    bool public claimGaugeRewardsOnUpdatePool = false;
    mapping(uint256 => bool) public pegStabilityModuleFeeEnabled; // pid => is enabled
    mapping(uint256 => uint256) public pegStabilityModuleFee; // pid => fee in basis points (1000 = 100%)
    uint256 public minClaimThreshold = 1e12; // 0.000001 GFANG

    IBlackholeVoter public blackholeVoter;

    address public bribesSafe;
    address public msigWallet;

    // Info of each pool.
    PoolInfo[] public poolInfo;

    // Info of each user that stakes LP tokens.
    mapping(uint256 => mapping(address => UserInfo)) public userInfo;
    // Pending rewards for each user in each pool (pending rewards accrued since last deposit/withdrawal)
    mapping(uint256 => mapping(address => uint256)) public pendingRewards;

    // Total allocation points. Must be the sum of all allocation points in all pools.
    uint256 public totalAllocPoint = 0;

    // The time when GFANG mining starts.
    uint256 public poolStartTime;

    // The time when GFANG mining ends.
    uint256 public poolEndTime;
    uint256 public sharePerSecond = 0 ether;
    uint256 public runningTime = 730 days;

    event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
    event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
    event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);
    event RewardPaid(address indexed user, uint256 amount);

    constructor(
        address _gfang,
        address _bribesSafe,
        uint256 _poolStartTime,
        address _blackholeVoter
    ) {
        require(block.timestamp < _poolStartTime, "pool cant be started in the past");
        if (_gfang != address(0)) gfang = IERC20(_gfang);
        if(_bribesSafe != address(0)) bribesSafe = _bribesSafe;

        poolStartTime = _poolStartTime;
        poolEndTime = _poolStartTime + runningTime;
        operator = msg.sender;
        blackholeVoter = IBlackholeVoter(_blackholeVoter);
        bribesSafe = _bribesSafe;
        msigWallet = _bribesSafe;
    }

    modifier onlyOperator() {
        require(operator == msg.sender, "GFangRewardPool: caller is not the operator");
        _;
    }

    function poolLength() external view returns (uint256) {
        return poolInfo.length;
    }

    function checkPoolDuplicate(IERC20 _token) internal view {
        uint256 length = poolInfo.length;
        for (uint256 pid = 0; pid < length; ++pid) {
            require(poolInfo[pid].token != _token, "GFangRewardPool: existing pool?");
        }
    }

    // bulk add pools
    function addBulk(uint256[] calldata _allocPoints, uint256[] calldata _depFees, IERC20[] calldata _tokens, bool _withUpdate, uint256 _lastRewardTime) external onlyOperator {
        require(_allocPoints.length == _depFees.length && _allocPoints.length == _tokens.length, "FangGenesisRewardPool: invalid length");
        for (uint256 i = 0; i < _allocPoints.length; i++) {
            add(_allocPoints[i], _depFees[i], _tokens[i], _withUpdate, _lastRewardTime);
        }
    }

    // Add new lp to the pool. Can only be called by operator.
    function add(
        uint256 _allocPoint,
        uint256 _depFee,
        IERC20 _token,
        bool _withUpdate,
        uint256 _lastRewardTime
    ) public onlyOperator {
        checkPoolDuplicate(_token);
        if (_withUpdate) {
            massUpdatePools();
        }
        if (block.timestamp < poolStartTime) {
            // chef is sleeping
            if (_lastRewardTime == 0) {
                _lastRewardTime = poolStartTime;
            } else {
                if (_lastRewardTime < poolStartTime) {
                    _lastRewardTime = poolStartTime;
                }
            }
        } else {
            // chef is cooking
            if (_lastRewardTime == 0 || _lastRewardTime < block.timestamp) {
                _lastRewardTime = block.timestamp;
            }
        }
        bool _isStarted = (_lastRewardTime <= poolStartTime) || (_lastRewardTime <= block.timestamp);
        poolInfo.push(PoolInfo({
            token: _token,
            depFee: _depFee,
            allocPoint: _allocPoint,
            poolGfangPerSec: _allocPoint,
            lastRewardTime: _lastRewardTime,
            accGfangPerShare: 0,
            isStarted: _isStarted,
            gaugeInfo: GaugeInfo(false, address(0), GaugeDex.NONE) // default to no gauge
        }));
        // enableGauge(poolInfo.length - 1);

        pegStabilityModuleFeeEnabled[poolInfo.length - 1] = true; // default to false
        pegStabilityModuleFee[poolInfo.length - 1] = 350; // default to 35%
        
        if (_isStarted) {
            totalAllocPoint = totalAllocPoint.add(_allocPoint);
            sharePerSecond = sharePerSecond.add(_allocPoint);
        }
    }

    // Update the given pool's GFANG allocation point. Can only be called by the operator.
    function set(uint256 _pid, uint256 _allocPoint, uint256 _depFee) public onlyOperator {
        massUpdatePools();

        PoolInfo storage pool = poolInfo[_pid];
        require(_depFee < 200);  // deposit fee cant be more than 2%;
        pool.depFee = _depFee;

        if (pool.isStarted) {
            totalAllocPoint = totalAllocPoint.sub(pool.allocPoint).add(_allocPoint);
            sharePerSecond = sharePerSecond.sub(pool.poolGfangPerSec).add(_allocPoint);
        }
        pool.allocPoint = _allocPoint;
        pool.poolGfangPerSec = _allocPoint;
    }

    function bulkSet(uint256[] calldata _pids, uint256[] calldata _allocPoints, uint256[] calldata _depFees) external onlyOperator {
        require(_pids.length == _allocPoints.length && _pids.length == _depFees.length, "GFangRewardPool: invalid length");
        for (uint256 i = 0; i < _pids.length; i++) {
            set(_pids[i], _allocPoints[i], _depFees[i]);
        }
    }

    // Return accumulate rewards over the given _from to _to block.
    function getGeneratedReward(uint256 _fromTime, uint256 _toTime) public view returns (uint256) {
        if (_fromTime >= _toTime) return 0;
        if (_toTime >= poolEndTime) {
            if (_fromTime >= poolEndTime) return 0;
            if (_fromTime <= poolStartTime) return poolEndTime.sub(poolStartTime).mul(sharePerSecond);
            return poolEndTime.sub(_fromTime).mul(sharePerSecond);
        } else {
            if (_toTime <= poolStartTime) return 0;
            if (_fromTime <= poolStartTime) return _toTime.sub(poolStartTime).mul(sharePerSecond);
            return _toTime.sub(_fromTime).mul(sharePerSecond);
        }
    }

    // View function to see pending GFANGs on frontend.
    function pendingShare(uint256 _pid, address _user) public view returns (uint256) {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_user];
        uint256 accGfangPerShare = pool.accGfangPerShare;
        uint256 tokenSupply = pool.gaugeInfo.isGauge ? IERC20(pool.gaugeInfo.gauge).balanceOf(address(this)) : pool.token.balanceOf(address(this));
        if (block.timestamp > pool.lastRewardTime && tokenSupply != 0) {
            uint256 _generatedReward = getGeneratedReward(pool.lastRewardTime, block.timestamp);
            uint256 _gfangReward = _generatedReward.mul(pool.allocPoint).div(totalAllocPoint);
            accGfangPerShare = accGfangPerShare.add(_gfangReward.mul(1e18).div(tokenSupply));
        }
        return user.amount.mul(accGfangPerShare).div(1e18).sub(user.rewardDebt);
    }

    // View function to see pending GFANGs on frontend and any other pending rewards accumulated.
    function pendingShareAndPendingRewards(uint256 _pid, address _user) external view returns (uint256) {
        uint256 _pendingShare = pendingShare(_pid, _user);
        return _pendingShare.add(pendingRewards[_pid][_user]);
    }

    function massUpdatePools() public {
        uint256 length = poolInfo.length;
        for (uint256 pid = 0; pid < length; ++pid) {
            updatePool(pid);
            updatePoolWithGaugeDeposit(pid);
        }
    }

    // massUpdatePoolsInRange
    function massUpdatePoolsInRange(uint256 _fromPid, uint256 _toPid) public {
        require(_fromPid <= _toPid, "GFangRewardPool: invalid range");
        for (uint256 pid = _fromPid; pid <= _toPid; ++pid) {
            updatePool(pid);
            updatePoolWithGaugeDeposit(pid);
        }
    }

    // Update reward variables of the given pool to be up-to-date.
    function updatePool(uint256 _pid) private {
        updatePoolWithGaugeDeposit(_pid);
        PoolInfo storage pool = poolInfo[_pid];
        if (block.timestamp <= pool.lastRewardTime) {
            return;
        }
        uint256 tokenSupply = pool.gaugeInfo.isGauge ? IERC20(pool.gaugeInfo.gauge).balanceOf(address(this)) : pool.token.balanceOf(address(this));
        if (tokenSupply == 0) {
            pool.lastRewardTime = block.timestamp;
            return;
        }
        if (!pool.isStarted) {
            pool.isStarted = true;
            totalAllocPoint = totalAllocPoint.add(pool.allocPoint);
            sharePerSecond = sharePerSecond.add(pool.poolGfangPerSec);
        }
        if (totalAllocPoint > 0) {
            uint256 _generatedReward = getGeneratedReward(pool.lastRewardTime, block.timestamp);
            uint256 _gfangReward = _generatedReward.mul(pool.allocPoint).div(totalAllocPoint);
            pool.accGfangPerShare = pool.accGfangPerShare.add(_gfangReward.mul(1e18).div(tokenSupply));
        }
        pool.lastRewardTime = block.timestamp;
        if (claimGaugeRewardsOnUpdatePool) {claimGaugeRewards(_pid);}
    }
    
    // Deposit LP tokens to earn rewards
    function updatePoolWithGaugeDeposit(uint256 _pid) public {
        PoolInfo storage pool = poolInfo[_pid];
        address gauge = pool.gaugeInfo.gauge;
        uint256 balance = pool.token.balanceOf(address(this));
        // Do nothing if this pool doesn't have a gauge
        if (pool.gaugeInfo.isGauge) {
            // Do nothing if the LP token in the MC is empty
            if (balance > 0) {
                // Approve to the gauge
                if (pool.token.allowance(address(this), gauge) < balance ){
                    pool.token.approve(gauge, type(uint256).max);
                }
                // Deposit to the gauge
                _depositToGauge(_pid, balance);
            }
        }
    }

    function _depositToGauge(uint256 _pid, uint256 _balance) internal {
        PoolInfo storage pool = poolInfo[_pid];
        if (pool.gaugeInfo.gaugeDex == GaugeDex.BLACKHOLE) {
            IBlackholeGauge(pool.gaugeInfo.gauge).deposit(_balance);
        }
    }

    // Claim rewards to treasury
    function claimGaugeRewards(uint256 _pid) public {
        PoolInfo storage pool = poolInfo[_pid];
        if (pool.gaugeInfo.isGauge) {
            if (pool.gaugeInfo.gaugeDex == GaugeDex.BLACKHOLE) {
                _claimBlackholeRewards(_pid);
            }   
        }
    }

    function claimAllFarmRewards() public onlyOperator {
        uint256 length = poolInfo.length;
        for (uint256 pid = 0; pid < length; ++pid) {
            claimGaugeRewards(pid);
        }
    }

    function _claimBlackholeRewards(uint256 _pid) internal {
        PoolInfo storage pool = poolInfo[_pid];
        address gaugeRewardTokenAddress = IBlackholeGauge(pool.gaugeInfo.gauge).rewardToken();
        IBlackholeGauge(pool.gaugeInfo.gauge).getReward();
        
        IERC20 rewardToken = IERC20(gaugeRewardTokenAddress);
        uint256 rewardAmount = rewardToken.balanceOf(address(this));

        if (rewardAmount > 0) {
            rewardToken.safeTransfer(bribesSafe, rewardAmount);
        }
    }

    function enableGauge(uint256 _pid, GaugeDex _gaugeDex) public onlyOperator {
        if (_gaugeDex == GaugeDex.BLACKHOLE) {
            _enableGaugeBlackhole(_pid);
        }
    }

    function _enableGaugeBlackhole(uint256 _pid) internal {
        address gauge = blackholeVoter.gauges(address(poolInfo[_pid].token));
        if (gauge != address(0)) {
            poolInfo[_pid].gaugeInfo = GaugeInfo(true, gauge, GaugeDex.BLACKHOLE);
        }
    }

    function disableGauge(uint256 _pid) public onlyOperator {
        _withdrawAllFromGauge(_pid);
        poolInfo[_pid].gaugeInfo = GaugeInfo(false, address(0), GaugeDex.NONE);
    }

    function _withdrawAllFromGauge(uint256 _pid) internal {
        PoolInfo storage pool = poolInfo[_pid];
        if (pool.gaugeInfo.gaugeDex == GaugeDex.BLACKHOLE) {
            IBlackholeGauge(pool.gaugeInfo.gauge).withdrawAll();
        }
    }

    // Withdraw LP from the gauge
    function withdrawFromGauge(uint256 _pid, uint256 _amount) internal {
        PoolInfo storage pool = poolInfo[_pid];
        // Do nothing if this pool doesn't have a gauge
        if (pool.gaugeInfo.isGauge) {
            // Withdraw from the gauge
            if (pool.gaugeInfo.gaugeDex == GaugeDex.BLACKHOLE) {
                IBlackholeGauge(pool.gaugeInfo.gauge).withdraw(_amount);
            }
        }
    }

    // Deposit LP tokens.
    function deposit(uint256 _pid, uint256 _amount) public nonReentrant {
        address _sender = msg.sender;
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_sender];
        updatePool(_pid);
        if (user.amount > 0) {
            uint256 _pending = user.amount.mul(pool.accGfangPerShare).div(1e18).sub(user.rewardDebt);
            if (_pending > 0) {
                // safeGfangTransfer(_sender, _pending);
                // emit RewardPaid(_sender, _pending);

                // accrue pending rewards to be claimed later
                pendingRewards[_pid][_sender] = pendingRewards[_pid][_sender].add(_pending);
            }
        }
        if (_amount > 0 ) {
            pool.token.safeTransferFrom(_sender, address(this), _amount);
            uint256 depositDebt = _amount.mul(pool.depFee).div(10000);
            user.amount = user.amount.add(_amount.sub(depositDebt));
            pool.token.safeTransfer(bribesSafe, depositDebt);
        }
        updatePoolWithGaugeDeposit(_pid);
        user.rewardDebt = user.amount.mul(pool.accGfangPerShare).div(1e18);
        emit Deposit(_sender, _pid, _amount);
    }

    // Withdraw LP tokens.
    function withdraw(uint256 _pid, uint256 _amount) public payable nonReentrant {
        address _sender = msg.sender;
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_sender];
        require(user.amount >= _amount, "withdraw: not good");
        updatePool(_pid);
        updatePoolWithGaugeDeposit(_pid);
        uint256 _pending = user.amount.mul(pool.accGfangPerShare).div(1e18).sub(user.rewardDebt);
        if (_pending > 0) {
            // safeGfangTransfer(_sender, _pending);
            // emit RewardPaid(_sender, _pending);

            // accrue pending rewards to be claimed later
            pendingRewards[_pid][_sender] = pendingRewards[_pid][_sender].add(_pending);
        }
        if (_amount > 0) {
            user.amount = user.amount.sub(_amount);
            withdrawFromGauge(_pid, _amount);
            pool.token.safeTransfer(_sender, _amount);
        }
        user.rewardDebt = user.amount.mul(pool.accGfangPerShare).div(1e18);
        emit Withdraw(_sender, _pid, _amount);
    }

    function harvest(uint256 _pid) public payable nonReentrant { 
        address _sender = msg.sender;
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_sender];

        // Ensure rewards are updated
        updatePool(_pid);
        updatePoolWithGaugeDeposit(_pid);

        // Calculate the latest pending rewards
        uint256 _pending = user.amount.mul(pool.accGfangPerShare).div(1e18).sub(user.rewardDebt);
        uint256 _accumulatedPending = pendingRewards[_pid][_sender];
        uint256 _rewardsToClaim = _pending.add(_accumulatedPending);

        // Ensure that the user is claiming an amount above the minimum threshold
        require(_rewardsToClaim >= minClaimThreshold, "Claim amount below minimum threshold");

        if (_rewardsToClaim > 0) {
            pendingRewards[_pid][_sender] = 0;

            uint256 amountEthToPay = 0;
            if (pegStabilityModuleFeeEnabled[_pid]) {
                uint256 currentGFANGPriceInEth = gfangOracle.twap(address(gfang), 1e18);
                amountEthToPay = (currentGFANGPriceInEth.mul(_rewardsToClaim).div(1e18)).mul(pegStabilityModuleFee[_pid]).div(1000);
                require(msg.value >= amountEthToPay, "insufficient Eth for PSM cost");
            } else {
                require(msg.value == 0, "GFangRewardPool: invalid msg.value");
            }

            safeGfangTransfer(_sender, _rewardsToClaim);
            emit RewardPaid(_sender, _rewardsToClaim);

            if (pegStabilityModuleFeeEnabled[_pid] && msg.value > amountEthToPay) {
                uint256 refundAmount = msg.value - amountEthToPay;
                (bool success, ) = _sender.call{value: refundAmount}("");
                require(success, "Refund failed");
            }
        }
        // Update the user’s reward debt
        user.rewardDebt = user.amount.mul(pool.accGfangPerShare).div(1e18);
    }

    function harvestAll() public payable nonReentrant {
        address _sender = msg.sender;
        uint256 length = poolInfo.length;
        uint256 totalUserRewardsToClaim = 0;
        uint256 amountEthToPay = 0;

        for (uint256 pid = 0; pid < length; ++pid) {
            PoolInfo storage pool = poolInfo[pid];
            UserInfo storage user = userInfo[pid][_sender];

            // Ensure rewards are updated
            updatePool(pid);
            updatePoolWithGaugeDeposit(pid);

            // Calculate the latest pending rewards
            uint256 _pending = user.amount.mul(pool.accGfangPerShare).div(1e18).sub(user.rewardDebt);
            uint256 _accumulatedPending = pendingRewards[pid][_sender];
            uint256 _rewardsToClaim = _pending.add(_accumulatedPending);

            if (_rewardsToClaim > 0) {
                pendingRewards[pid][_sender] = 0;
                totalUserRewardsToClaim = totalUserRewardsToClaim.add(_rewardsToClaim);

                if (pegStabilityModuleFeeEnabled[pid]) {
                    uint256 currentGFANGPriceInEth = gfangOracle.twap(address(gfang), 1e18);
                    amountEthToPay = amountEthToPay.add((currentGFANGPriceInEth.mul(_rewardsToClaim).div(1e18)).mul(pegStabilityModuleFee[pid]).div(1000));
                }
            }
            // Update the user’s reward debt
            user.rewardDebt = user.amount.mul(pool.accGfangPerShare).div(1e18);
        }

        // Ensure that the user is claiming an amount above the minimum threshold
        require(totalUserRewardsToClaim >= minClaimThreshold, "Claim amount below minimum threshold");
        if (amountEthToPay == 0) {
            require(msg.value == 0, "GFangRewardPool: invalid msg.value");
        } else {
            require(msg.value >= amountEthToPay, "insufficient Eth for PSM cost");
        }

        if (totalUserRewardsToClaim > 0) {
            safeGfangTransfer(_sender, totalUserRewardsToClaim);
            emit RewardPaid(_sender, totalUserRewardsToClaim);

            if (msg.value > amountEthToPay) {
                uint256 refundAmount = msg.value - amountEthToPay;
                (bool success, ) = _sender.call{value: refundAmount}("");
                require(success, "Refund failed");
            }
        }
    }

    // Withdraw without caring about rewards. EMERGENCY ONLY.
    function emergencyWithdraw(uint256 _pid) public nonReentrant {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][msg.sender];
        uint256 _amount = user.amount;
        withdrawFromGauge(_pid, _amount);
        pendingRewards[_pid][msg.sender] = 0;
        user.amount = 0;
        user.rewardDebt = 0;
        pool.token.safeTransfer(msg.sender, _amount);
        emit EmergencyWithdraw(msg.sender, _pid, _amount);
    }

    // Safe gfang transfer function, just in case if rounding error causes pool to not have enough GFANGs.
    function safeGfangTransfer(address _to, uint256 _amount) internal {
        uint256 _gfangBal = gfang.balanceOf(address(this));
        if (_gfangBal > 0) {
            if (_amount > _gfangBal) {
                gfang.safeTransfer(_to, _gfangBal);
            } else {
                gfang.safeTransfer(_to, _amount);
            }
        }
    }

    function setOperator(address _operator) external onlyOperator {
        operator = _operator;
    }

    function setBribesSafe(address _bribesSafe) public onlyOperator {
        bribesSafe = _bribesSafe;
    }

    function setMsigWallet(address _msigWallet) public onlyOperator {
        msigWallet = _msigWallet;
    }

    function setPegStabilityModuleFee(uint256 _pegStabilityModuleFee, uint256 _pid) external onlyOperator {
        require(_pegStabilityModuleFee <= 750, "GFangRewardPool: invalid peg stability module fee"); // max 75%
        pegStabilityModuleFee[_pid] = _pegStabilityModuleFee;
    }

    function setGFangOracle(IOracle _gfangOracle) external onlyOperator {
        gfangOracle = _gfangOracle;
    }

    function setPegStabilityModuleFeeEnabled(bool _enabled, uint256 _pid) external onlyOperator {
        pegStabilityModuleFeeEnabled[_pid] = _enabled;
    }

    function setMinClaimThreshold(uint256 _minClaimThreshold) external onlyOperator {
        require(_minClaimThreshold >= 0, "GFangRewardPool: invalid min claim threshold");
        require(_minClaimThreshold <= 1e18, "GFangRewardPool: invalid max claim threshold");
        minClaimThreshold = _minClaimThreshold;
    }

    function setClaimGaugeRewardsOnUpdatePool(bool _claimGaugeRewardsOnUpdatePool) external onlyOperator {
        claimGaugeRewardsOnUpdatePool = _claimGaugeRewardsOnUpdatePool;
    }

    function governanceRecoverUnsupported(IERC20 _token, uint256 amount, address to) external onlyOperator {
        uint256 length = poolInfo.length;
        for (uint256 pid = 0; pid < length; ++pid) {
            PoolInfo storage pool = poolInfo[pid];
            require(_token != pool.token, "ShareRewardPool: Token cannot be pool token");
        }
        _token.safeTransfer(to, amount);
    }

    /**
     * @notice Collects the Eth.
     * @param amount The amount of Eth to collect
     */

    function collectEth(uint256 amount) public onlyOperator {
        (bool sent,) = bribesSafe.call{value: amount}("");
        require(sent, "failed to send Eth");
    }

    function collectEthMsig(uint256 amount) public onlyOperator {
        (bool sent,) = msigWallet.call{value: amount}("");
        require(sent, "failed to send Eth");
    }
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.26;

interface IBlackholeGauge {
    /// @notice Get the amount of stakingToken deposited by an account
    function balanceOf(address) external view returns (uint256);

    /// @notice rewardToken address
    function rewardToken() external view returns (address);

    /// @notice claims rewards (blackhole + any external LP Incentives)
    function getReward() external;

    /// @notice deposit LP tokens to the gauge
    /// @param amount the amount of LP tokens to withdraw
    function deposit(uint256 amount) external;

    /// @notice withdraws all fungible LP tokens from legacy gauges
    function withdrawAll() external;

    /// @notice withdraws fungible LP tokens from legacy gauges
    /// @param amount the amount of LP tokens to withdraw
    function withdraw(uint256 amount) external;
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.26;
pragma abicoder v2;

interface IBlackholeVoter {
    /// @notice returns the address of the pool's gauge, if any
    /// @param pool pool address
    /// @return gauge address
    function gauges(address pool) external view returns (address);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IBasisAsset {
    function mint(address recipient, uint256 amount) external returns (bool);

    function burn(uint256 amount) external;

    function burnFrom(address from, uint256 amount) external;

    function isOperator() external returns (bool);

    function operator() external view returns (address);

    function transferOperator(address newOperator_) external;
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.26;

interface IBlackholeRouter {
    error EXPIRED();
    error IDENTICAL();
    error ZERO_ADDRESS();
    error INSUFFICIENT_AMOUNT();
    error INSUFFICIENT_LIQUIDITY();
    error INSUFFICIENT_OUTPUT_AMOUNT();
    error INVALID_PATH();
    error INSUFFICIENT_B_AMOUNT();
    error INSUFFICIENT_A_AMOUNT();
    error EXCESSIVE_INPUT_AMOUNT();
    error ETH_TRANSFER_FAILED();
    error INVALID_RESERVES();

    struct route {
        /// @dev token pair address
        address pair;
        /// @dev token from
        address from;
        /// @dev token to
        address to;
        /// @dev is stable route
        bool stable;
        /// @dev is concentrated route
        bool concentrated;
        /// @dev receiver of the output
        address receiver;
    }

    /// @notice sorts the tokens to see what the expected LP output would be for token0 and token1 (A/B)
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @return token0 address of which becomes token0
    /// @return token1 address of which becomes token1
    function sortTokens(
        address tokenA,
        address tokenB
    ) external pure returns (address token0, address token1);

    /// @notice calculates the CREATE2 address for a pair without making any external calls
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @return pair address of the pair
    function pairFor(
        address tokenA,
        address tokenB,
        bool stable
    ) external view returns (address pair);

    /// @notice fetches and sorts the reserves for a pair
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @return reserveA get the reserves for tokenA
    /// @return reserveB get the reserves for tokenB
    function getReserves(
        address tokenA,
        address tokenB,
        bool stable
    ) external view returns (uint256 reserveA, uint256 reserveB);

    /// @notice performs chained getAmountOut calculations on any number of pairs
    /// @param amountIn the amount of tokens of routes[0] to swap
    /// @param routes the struct of the hops the swap should take
    /// @return amounts uint array of the amounts out
    function getAmountsOut(
        uint256 amountIn,
        route[] memory routes
    ) external view returns (uint256[] memory amounts);

    /// @notice performs chained getAmountOut calculations on any number of pairs
    /// @param amountIn amount of tokenIn
    /// @param tokenIn address of the token going in
    /// @param tokenOut address of the token coming out
    /// @return amount uint amount out
    /// @return stable if the curve used is stable or not
    function getAmountOut(
        uint256 amountIn,
        address tokenIn,
        address tokenOut
    ) external view returns (uint256 amount, bool stable);

    /// @notice performs calculations to determine the expected state when adding liquidity
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param amountADesired amount of tokenA desired to be added
    /// @param amountBDesired amount of tokenB desired to be added
    /// @return amountA amount of tokenA added
    /// @return amountB amount of tokenB added
    /// @return liquidity liquidity value added
    function quoteAddLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 amountADesired,
        uint256 amountBDesired
    )
        external
        view
        returns (uint256 amountA, uint256 amountB, uint256 liquidity);

    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param liquidity liquidity value to remove
    /// @return amountA amount of tokenA removed
    /// @return amountB amount of tokenB removed
    function quoteRemoveLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 liquidity
    ) external view returns (uint256 amountA, uint256 amountB);

    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param amountADesired amount of tokenA desired to be added
    /// @param amountBDesired amount of tokenB desired to be added
    /// @param amountAMin slippage for tokenA calculated from this param
    /// @param amountBMin slippage for tokenB calculated from this param
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    /// @return liquidity amount of liquidity minted
    function addLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB, uint256 liquidity);

    /// @param token the address of token
    /// @param stable if the pair is using the stable curve
    /// @param amountTokenDesired desired amount for token
    /// @param amountTokenMin slippage for token
    /// @param amountETHMin minimum amount of ETH added (slippage)
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountToken amount of the token used
    /// @return amountETH amount of ETH used
    /// @return liquidity amount of liquidity minted
    function addLiquidityETH(
        address token,
        bool stable,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (uint256 amountToken, uint256 amountETH, uint256 liquidity);
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param amountADesired amount of tokenA desired to be added
    /// @param amountBDesired amount of tokenB desired to be added
    /// @param amountAMin slippage for tokenA calculated from this param
    /// @param amountBMin slippage for tokenB calculated from this param
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    /// @return liquidity amount of liquidity minted
    function addLiquidityAndStake(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB, uint256 liquidity);

    /// @notice adds liquidity to a legacy pair using ETH, and stakes it into a gauge on "to's" behalf
    /// @param token the address of token
    /// @param stable if the pair is using the stable curve
    /// @param amountTokenDesired amount of token to be used
    /// @param amountTokenMin slippage of token
    /// @param amountETHMin slippage of ETH
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    /// @return liquidity amount of liquidity minted
    function addLiquidityETHAndStake(
        address token,
        bool stable,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (uint256 amountA, uint256 amountB, uint256 liquidity);
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param liquidity amount of LP tokens to remove
    /// @param amountAMin slippage of tokenA
    /// @param amountBMin slippage of tokenB
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    function removeLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB);
    /// @param token address of the token
    /// @param stable if the pair is using the stable curve
    /// @param liquidity liquidity tokens to remove
    /// @param amountTokenMin slippage of token
    /// @param amountETHMin slippage of ETH
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountToken amount of token used
    /// @return amountETH amount of ETH used
    function removeLiquidityETH(
        address token,
        bool stable,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountToken, uint256 amountETH);
    /// @param amountIn amount to send ideally
    /// @param amountOutMin slippage of amount out
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        route[] memory routes,
        address to,
        uint deadline
    ) external returns (uint256[] memory amounts);
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapExactETHForTokens(
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);
    /// @param amountOut amount of tokens to get out
    /// @param amountInMax max amount of tokens to put in to achieve amountOut (slippage)
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapTokensForExactETH(
        uint amountOut,
        uint amountInMax,
        route[] calldata routes,
        address to,
        uint deadline
    ) external returns (uint256[] memory amounts);
    /// @param amountIn amount of tokens to swap
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapExactTokensForETH(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);
    /// @param amountOut exact amount out or revert
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapETHForExactTokens(
        uint amountOut,
        route[] calldata routes,
        address to,
        uint deadline
    ) external payable returns (uint256[] memory amounts);

    /// @param amountIn token amount to swap
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external;

    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external payable;

    /// @param amountIn token amount to swap
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external;

    /// @notice **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens)****
    /// @param token address of the token
    /// @param stable if the swap curve is stable
    /// @param liquidity liquidity value (lp tokens)
    /// @param amountTokenMin slippage of token
    /// @param amountETHMin slippage of ETH
    /// @param to address to send to
    /// @param deadline timestamp deadline
    /// @return amountToken amount of token received
    /// @return amountETH amount of ETH received
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        bool stable,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountToken, uint256 amountETH);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IFangRedeem {
    function redeemFang(uint256 amount) external; // Redeem Fang tokens for a reward
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IMasonry {
    function balanceOf(address _andras) external view returns (uint256);

    function earned(address _andras) external view returns (uint256);

    function canWithdraw(address _andras) external view returns (bool);

    function canClaimReward(address _andras) external view returns (bool);

    function epoch() external view returns (uint256);

    function nextEpochPoint() external view returns (uint256);

    function getTombPrice() external view returns (uint256);

    function setOperator(address _operator) external;

    function setLockUp(uint256 _withdrawLockupEpochs, uint256 _rewardLockupEpochs) external;

    function stake(uint256 _amount) external;

    function withdraw(uint256 _amount) external;

    function exit() external;

    function claimReward() external;

    function allocateSeigniorage(uint256 _amount) external;

    function governanceRecoverUnsupported(address _token, uint256 _amount, address _to) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IOracle {
    function update() external;

    function consult(address _token, uint256 _amountIn) external view returns (uint256 amountOut);

    function twap(address _token, uint256 _amountIn) external view returns (uint256 _amountOut);
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.26;

interface IShadowRouter {
    error EXPIRED();
    error IDENTICAL();
    error ZERO_ADDRESS();
    error INSUFFICIENT_AMOUNT();
    error INSUFFICIENT_LIQUIDITY();
    error INSUFFICIENT_OUTPUT_AMOUNT();
    error INVALID_PATH();
    error INSUFFICIENT_B_AMOUNT();
    error INSUFFICIENT_A_AMOUNT();
    error EXCESSIVE_INPUT_AMOUNT();
    error ETH_TRANSFER_FAILED();
    error INVALID_RESERVES();

    struct route {
        /// @dev token from
        address from;
        /// @dev token to
        address to;
        /// @dev is stable route
        bool stable;
    }

    /// @notice sorts the tokens to see what the expected LP output would be for token0 and token1 (A/B)
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @return token0 address of which becomes token0
    /// @return token1 address of which becomes token1
    function sortTokens(
        address tokenA,
        address tokenB
    ) external pure returns (address token0, address token1);

    /// @notice calculates the CREATE2 address for a pair without making any external calls
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @return pair address of the pair
    function pairFor(
        address tokenA,
        address tokenB,
        bool stable
    ) external view returns (address pair);

    /// @notice fetches and sorts the reserves for a pair
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @return reserveA get the reserves for tokenA
    /// @return reserveB get the reserves for tokenB
    function getReserves(
        address tokenA,
        address tokenB,
        bool stable
    ) external view returns (uint256 reserveA, uint256 reserveB);

    /// @notice performs chained getAmountOut calculations on any number of pairs
    /// @param amountIn the amount of tokens of routes[0] to swap
    /// @param routes the struct of the hops the swap should take
    /// @return amounts uint array of the amounts out
    function getAmountsOut(
        uint256 amountIn,
        route[] memory routes
    ) external view returns (uint256[] memory amounts);

    /// @notice performs chained getAmountOut calculations on any number of pairs
    /// @param amountIn amount of tokenIn
    /// @param tokenIn address of the token going in
    /// @param tokenOut address of the token coming out
    /// @return amount uint amount out
    /// @return stable if the curve used is stable or not
    function getAmountOut(
        uint256 amountIn,
        address tokenIn,
        address tokenOut
    ) external view returns (uint256 amount, bool stable);

    /// @notice performs calculations to determine the expected state when adding liquidity
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param amountADesired amount of tokenA desired to be added
    /// @param amountBDesired amount of tokenB desired to be added
    /// @return amountA amount of tokenA added
    /// @return amountB amount of tokenB added
    /// @return liquidity liquidity value added
    function quoteAddLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 amountADesired,
        uint256 amountBDesired
    )
        external
        view
        returns (uint256 amountA, uint256 amountB, uint256 liquidity);

    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param liquidity liquidity value to remove
    /// @return amountA amount of tokenA removed
    /// @return amountB amount of tokenB removed
    function quoteRemoveLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 liquidity
    ) external view returns (uint256 amountA, uint256 amountB);

    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param amountADesired amount of tokenA desired to be added
    /// @param amountBDesired amount of tokenB desired to be added
    /// @param amountAMin slippage for tokenA calculated from this param
    /// @param amountBMin slippage for tokenB calculated from this param
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    /// @return liquidity amount of liquidity minted
    function addLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB, uint256 liquidity);

    /// @param token the address of token
    /// @param stable if the pair is using the stable curve
    /// @param amountTokenDesired desired amount for token
    /// @param amountTokenMin slippage for token
    /// @param amountETHMin minimum amount of ETH added (slippage)
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountToken amount of the token used
    /// @return amountETH amount of ETH used
    /// @return liquidity amount of liquidity minted
    function addLiquidityETH(
        address token,
        bool stable,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (uint256 amountToken, uint256 amountETH, uint256 liquidity);
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param amountADesired amount of tokenA desired to be added
    /// @param amountBDesired amount of tokenB desired to be added
    /// @param amountAMin slippage for tokenA calculated from this param
    /// @param amountBMin slippage for tokenB calculated from this param
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    /// @return liquidity amount of liquidity minted
    function addLiquidityAndStake(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB, uint256 liquidity);

    /// @notice adds liquidity to a legacy pair using ETH, and stakes it into a gauge on "to's" behalf
    /// @param token the address of token
    /// @param stable if the pair is using the stable curve
    /// @param amountTokenDesired amount of token to be used
    /// @param amountTokenMin slippage of token
    /// @param amountETHMin slippage of ETH
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    /// @return liquidity amount of liquidity minted
    function addLiquidityETHAndStake(
        address token,
        bool stable,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (uint256 amountA, uint256 amountB, uint256 liquidity);
    /// @param tokenA the address of tokenA
    /// @param tokenB the address of tokenB
    /// @param stable if the pair is using the stable curve
    /// @param liquidity amount of LP tokens to remove
    /// @param amountAMin slippage of tokenA
    /// @param amountBMin slippage of tokenB
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountA amount of tokenA used
    /// @return amountB amount of tokenB used
    function removeLiquidity(
        address tokenA,
        address tokenB,
        bool stable,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB);
    /// @param token address of the token
    /// @param stable if the pair is using the stable curve
    /// @param liquidity liquidity tokens to remove
    /// @param amountTokenMin slippage of token
    /// @param amountETHMin slippage of ETH
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amountToken amount of token used
    /// @return amountETH amount of ETH used
    function removeLiquidityETH(
        address token,
        bool stable,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountToken, uint256 amountETH);
    /// @param amountIn amount to send ideally
    /// @param amountOutMin slippage of amount out
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        route[] memory routes,
        address to,
        uint deadline
    ) external returns (uint256[] memory amounts);
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapExactETHForTokens(
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);
    /// @param amountOut amount of tokens to get out
    /// @param amountInMax max amount of tokens to put in to achieve amountOut (slippage)
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapTokensForExactETH(
        uint amountOut,
        uint amountInMax,
        route[] calldata routes,
        address to,
        uint deadline
    ) external returns (uint256[] memory amounts);
    /// @param amountIn amount of tokens to swap
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapExactTokensForETH(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);
    /// @param amountOut exact amount out or revert
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    /// @return amounts amounts returned
    function swapETHForExactTokens(
        uint amountOut,
        route[] calldata routes,
        address to,
        uint deadline
    ) external payable returns (uint256[] memory amounts);

    /// @param amountIn token amount to swap
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external;

    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external payable;

    /// @param amountIn token amount to swap
    /// @param amountOutMin slippage of token
    /// @param routes the hops the swap should take
    /// @param to the address the liquidity tokens should be minted to
    /// @param deadline timestamp deadline
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        route[] calldata routes,
        address to,
        uint256 deadline
    ) external;

    /// @notice **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens)****
    /// @param token address of the token
    /// @param stable if the swap curve is stable
    /// @param liquidity liquidity value (lp tokens)
    /// @param amountTokenMin slippage of token
    /// @param amountETHMin slippage of ETH
    /// @param to address to send to
    /// @param deadline timestamp deadline
    /// @return amountToken amount of token received
    /// @return amountETH amount of ETH received
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        bool stable,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountToken, uint256 amountETH);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint256 value);
    event Transfer(address indexed from, address indexed to, uint256 value);

    function name() external pure returns (string memory);

    function symbol() external pure returns (string memory);

    function decimals() external pure returns (uint8);

    function totalSupply() external view returns (uint256);

    function balanceOf(address owner) external view returns (uint256);

    function allowance(address owner, address spender) external view returns (uint256);

    function approve(address spender, uint256 value) external returns (bool);

    function transfer(address to, uint256 value) external returns (bool);

    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);

    function PERMIT_TYPEHASH() external pure returns (bytes32);

    function nonces(address owner) external view returns (uint256);

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    event Mint(address indexed sender, uint256 amount0, uint256 amount1);
    event Burn(address indexed sender, uint256 amount0, uint256 amount1, address indexed to);
    event Swap(address indexed sender, uint256 amount0In, uint256 amount1In, uint256 amount0Out, uint256 amount1Out, address indexed to);
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint256);

    function factory() external view returns (address);

    function token0() external view returns (address);

    function token1() external view returns (address);

    function getReserves()
        external
        view
        returns (
            uint112 reserve0,
            uint112 reserve1,
            uint32 blockTimestampLast
        );

    function price0CumulativeLast() external view returns (uint256);

    function price1CumulativeLast() external view returns (uint256);

    function kLast() external view returns (uint256);

    function mint(address to) external returns (uint256 liquidity);

    function burn(address to) external returns (uint256 amount0, uint256 amount1);

    function swap(
        uint256 amount0Out,
        uint256 amount1Out,
        address to,
        bytes calldata data
    ) external;

    function skim(address to) external;

    function sync() external;

    function initialize(address, address) external;
}

pragma solidity >=0.5.0;

interface IWETH {
    function deposit() external payable;
    function transfer(address to, uint value) external returns (bool);
    function withdraw(uint) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

library Babylonian {
    function sqrt(uint256 y) internal pure returns (uint256 z) {
        if (y > 3) {
            z = y;
            uint256 x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
        // else z = 0
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

library TransferHelper {
    function safeApprove(address token, address to, uint value) internal {
        // bytes4(keccak256(bytes('approve(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
    }

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

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

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

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "./shadow/interfaces/IPool.sol";
import "./owner/Operator.sol";

/**************************************************************************************************************************************************

 /$$$$$$$$                                 /$$$$$$$$ /$$                                                  
| $$_____/                                | $$_____/|__/                                                  
| $$    /$$$$$$  /$$$$$$$   /$$$$$$       | $$       /$$ /$$$$$$$   /$$$$$$  /$$$$$$$   /$$$$$$$  /$$$$$$ 
| $$$$$|____  $$| $$__  $$ /$$__  $$      | $$$$$   | $$| $$__  $$ |____  $$| $$__  $$ /$$_____/ /$$__  $$
| $$__/ /$$$$$$$| $$  \ $$| $$  \ $$      | $$__/   | $$| $$  \ $$  /$$$$$$$| $$  \ $$| $$      | $$$$$$$$
| $$   /$$__  $$| $$  | $$| $$  | $$      | $$      | $$| $$  | $$ /$$__  $$| $$  | $$| $$      | $$_____/
| $$  |  $$$$$$$| $$  | $$|  $$$$$$$      | $$      | $$| $$  | $$|  $$$$$$$| $$  | $$|  $$$$$$$|  $$$$$$$
|__/   \_______/|__/  |__/ \____  $$      |__/      |__/|__/  |__/ \_______/|__/  |__/ \_______/ \_______/
                           /$$  \ $$                                                                      
                          |  $$$$$$/                                                                      
                           \______/                                                                       
                                                                                                                                                    
#### Website: https://fang.finance/
#### Author: kell

**************************************************************************************************************************************************/

contract OracleV2GFang is Operator {
    using SafeMath for uint256;

    address public token0;
    address public token1;
    uint256 public granularityToUse = 2; // 1 observation every 30 minutes
    bool public useTwap = true;
    bool public useInstantPrice = true;
    IPool public pair;

    constructor(IPool _pair) public {
        pair = _pair;
        token0 = pair.token0();
        token1 = pair.token1();
        // uint256 reserve0;
        // uint256 reserve1;
        // (reserve0, reserve1, ) = pair.getReserves();
        // require(reserve0 != 0 && reserve1 != 0, "Oracle: No reserves");
    }

    function update() external {
        pair.sync();
    }

    function consult(
        address _token,
        uint256 _amountIn
    ) external view returns (uint256 amountOut) {
        if (_token == token0) {
            amountOut = _quote(_token, _amountIn, 12);
        } else {
            require(_token == token1, "Oracle: Invalid token");
            amountOut = _quote(_token, _amountIn, 12);
        }
    }

    function twap(
        address _token,
        uint256 _amountIn
    ) external view returns (uint256 amountOut) {
        if (_token == token0) {
            if (useTwap) {
                amountOut = _quote(_token, _amountIn, granularityToUse);
            } else {
                if (useInstantPrice) {
                    amountOut = _getAmountOut(_token, _amountIn);
                } else {
                    amountOut = _current(_token, _amountIn);
                }
            }
        } else {
            require(_token == token1, "Oracle: Invalid token");
            if (useTwap) {
                amountOut = _quote(_token, _amountIn, granularityToUse);
            } else {
                if (useInstantPrice) {
                    amountOut = _getAmountOut(_token, _amountIn);
                } else {
                    amountOut = _current(_token, _amountIn);
                }
            }
        }
    }

    // Note the window parameter is removed as its always 1 (30min), granularity at 12 for example is (12 * 30min) = 6 hours
    function _quote(
        address tokenIn,
        uint256 amountIn,
        uint256 granularity // number of observations to query
    ) internal view returns (uint256 amountOut) {
        uint256 observationLength = IPool(pair).observationLength();
        require(
            granularity <= observationLength,
            "Oracle: Not enough observations"
        );

        uint256 price = IPool(pair).quote(tokenIn, amountIn, granularity);
        amountOut = price;
    }

    // Note the window parameter is removed as its always 1 (30min), granularity at 12 for example is (12 * 30min) = 6 hours
    function _getAmountOut(
        address tokenIn,
        uint256 amountIn
    ) internal view returns (uint256 amountOut) {
        uint256 reserve0;
        uint256 reserve1;
        (reserve0, reserve1, ) = IPool(pair).getReserves();
        require(reserve0 != 0 && reserve1 != 0, "Oracle: No reserves");

        uint256 price = IPool(pair).getAmountOut(amountIn, tokenIn);
        amountOut = price;
    }

    // Note the window parameter is removed as its always 1 (30min), granularity at 12 for example is (12 * 30min) = 6 hours
    function _current(
        address tokenIn,
        uint256 amountIn
    ) internal view returns (uint256 amountOut) {
        uint256 observationLength = IPool(pair).observationLength();
        require(
            observationLength > 0,
            "Oracle: Not enough observations"
        );

        uint256 price = IPool(pair).current(tokenIn, amountIn);
        amountOut = price;
    }

    function setGranularity(uint256 _granularity) external onlyOperator {
        granularityToUse = _granularity;
    }

    function setUseTwap(bool _useTwap) external onlyOperator {
        useTwap = _useTwap;
    }

    function setUseInstantPrice(bool _useInstantPrice) external onlyOperator {
        useInstantPrice = _useInstantPrice;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

contract Operator is Context, Ownable {
    address private _operator;

    event OperatorTransferred(address indexed previousOperator, address indexed newOperator);

    constructor() {
        _operator = _msgSender();
        emit OperatorTransferred(address(0), _operator);
    }

    function operator() public view returns (address) {
        return _operator;
    }

    modifier onlyOperator() {
        require(_operator == msg.sender, "operator: caller is not the operator");
        _;
    }

    function isOperator() public view returns (bool) {
        return _msgSender() == _operator;
    }

    function transferOperator(address newOperator_) public onlyOwner {
        _transferOperator(newOperator_);
    }

    function _transferOperator(address newOperator_) internal {
        require(newOperator_ != address(0), "operator: zero address given for new operator");
        emit OperatorTransferred(address(0), newOperator_);
        _operator = newOperator_;
    }

    function _renounceOperator() public onlyOwner {
        emit OperatorTransferred(_operator, address(0));
        _operator = address(0);
    }
}

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.26;

interface IPool {
    error NOT_AUTHORIZED();
    error UNSTABLE_RATIO();
    /// @dev safe transfer failed
    error STF();
    error OVERFLOW();
    /// @dev skim disabled
    error SD();
    /// @dev insufficient liquidity minted
    error ILM();
    /// @dev insufficient liquidity burned
    error ILB();
    /// @dev insufficient output amount
    error IOA();
    /// @dev insufficient input amount
    error IIA();
    error IL();
    error IT();
    error K();

    event Mint(address indexed sender, uint256 amount0, uint256 amount1);
    event Burn(
        address indexed sender,
        uint256 amount0,
        uint256 amount1,
        address indexed to
    );
    event Swap(
        address indexed sender,
        uint256 amount0In,
        uint256 amount1In,
        uint256 amount0Out,
        uint256 amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

        /// @notice Same as prices with with an additional window argument.
    ///         Window = 2 means 2 * 30min (or 1 hr) between observations
    /// @param tokenIn .
    /// @param amountIn .
    /// @param points .
    /// @param window .
    /// @return Array of TWAP prices
    function sample(
        address tokenIn,
        uint256 amountIn,
        uint256 points,
        uint256 window
    ) external view returns (uint256[] memory);

    function observations(uint256 index) external view returns (uint256 timestamp, uint256 reserve0Cumulative, uint256 reserve1Cumulative);

    function current(address tokenIn, uint256 amountIn) external view returns (uint256 amountOut);

    /// @notice Provides twap price with user configured granularity, up to the full window size
    /// @param tokenIn .
    /// @param amountIn .
    /// @param granularity .
    /// @return amountOut .
    function quote(address tokenIn, uint256 amountIn, uint256 granularity) external view returns (uint256 amountOut);

    /// @notice Get the number of observations recorded
    function observationLength() external view returns (uint256);

    /// @notice Address of token in the pool with the lower address value
    function token0() external view returns (address);

    /// @notice Address of token in the poool with the higher address value
    function token1() external view returns (address);

    /// @notice initialize the pool, called only once programatically
    function initialize(
        address _token0,
        address _token1,
        bool _stable
    ) external;

    /// @notice calculate the current reserves of the pool and their last 'seen' timestamp
    /// @return _reserve0 amount of token0 in reserves
    /// @return _reserve1 amount of token1 in reserves
    /// @return _blockTimestampLast the timestamp when the pool was last updated
    function getReserves()
        external
        view
        returns (
            uint112 _reserve0,
            uint112 _reserve1,
            uint32 _blockTimestampLast
        );

    /// @notice mint the pair tokens (LPs)
    /// @param to where to mint the LP tokens to
    /// @return liquidity amount of LP tokens to mint
    function mint(address to) external returns (uint256 liquidity);

    /// @notice burn the pair tokens (LPs)
    /// @param to where to send the underlying
    /// @return amount0 amount of amount0
    /// @return amount1 amount of amount1
    function burn(
        address to
    ) external returns (uint256 amount0, uint256 amount1);

    /// @notice direct swap through the pool
    function swap(
        uint256 amount0Out,
        uint256 amount1Out,
        address to,
        bytes calldata data
    ) external;

    /// @notice force balances to match reserves, can be used to harvest rebases from rebasing tokens or other external factors
    /// @param to where to send the excess tokens to
    function skim(address to) external;

    /// @notice force reserves to match balances, prevents skim excess if skim is enabled
    function sync() external;

    /// @notice set the pair fees contract address
    function setFeeRecipient(address _pairFees) external;

    /// @notice set the feesplit variable
    function setFeeSplit(uint256 _feeSplit) external;

    /// @notice sets the swap fee of the pair
    /// @dev max of 10_000 (10%)
    /// @param _fee the fee
    function setFee(uint256 _fee) external;

    /// @notice 'mint' the fees as LP tokens
    /// @dev this is used for protocol/voter fees
    function mintFee() external;

    /// @notice calculates the amount of tokens to receive post swap
    /// @param amountIn the token amount
    /// @param tokenIn the address of the token
    function getAmountOut(
        uint256 amountIn,
        address tokenIn
    ) external view returns (uint256 amountOut);

    /// @notice returns various metadata about the pair
    function metadata()
        external
        view
        returns (
            uint256 _decimals0,
            uint256 _decimals1,
            uint256 _reserve0,
            uint256 _reserve1,
            bool _stable,
            address _token0,
            address _token1
        );

    /// @notice returns the feeSplit of the pair
    function feeSplit() external view returns (uint256);

    /// @notice returns the fee of the pair
    function fee() external view returns (uint256);

    /// @notice returns the feeRecipient of the pair
    function feeRecipient() external view returns (address);

}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/utils/math/Math.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

import "./lib/Babylonian.sol";
import "./owner/Operator.sol";
import "./utils/ContractGuard.sol";
import "./interfaces/IBasisAsset.sol";
import "./interfaces/IOracle.sol";
import "./interfaces/IMasonry.sol";
import "./owner/Operator.sol";

/**************************************************************************************************************************************************

 /$$$$$$$$                                 /$$$$$$$$ /$$                                                  
| $$_____/                                | $$_____/|__/                                                  
| $$    /$$$$$$  /$$$$$$$   /$$$$$$       | $$       /$$ /$$$$$$$   /$$$$$$  /$$$$$$$   /$$$$$$$  /$$$$$$ 
| $$$$$|____  $$| $$__  $$ /$$__  $$      | $$$$$   | $$| $$__  $$ |____  $$| $$__  $$ /$$_____/ /$$__  $$
| $$__/ /$$$$$$$| $$  \ $$| $$  \ $$      | $$__/   | $$| $$  \ $$  /$$$$$$$| $$  \ $$| $$      | $$$$$$$$
| $$   /$$__  $$| $$  | $$| $$  | $$      | $$      | $$| $$  | $$ /$$__  $$| $$  | $$| $$      | $$_____/
| $$  |  $$$$$$$| $$  | $$|  $$$$$$$      | $$      | $$| $$  | $$|  $$$$$$$| $$  | $$|  $$$$$$$|  $$$$$$$
|__/   \_______/|__/  |__/ \____  $$      |__/      |__/|__/  |__/ \_______/|__/  |__/ \_______/ \_______/
                           /$$  \ $$                                                                      
                          |  $$$$$$/                                                                      
                           \______/                                                                       
                                                                                                                                                    
#### Website: https://fang.finance/
#### Author: kell

**************************************************************************************************************************************************/

contract Treasury is ContractGuard, Operator {
    using SafeERC20 for IERC20;
    using Address for address;
    using SafeMath for uint256;

    /* ========= CONSTANT VARIABLES ======== */

    uint256 public constant PERIOD = 6 hours;
    uint256 public constant BASIS_DIVISOR = 100000000; // 100%

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

    // flags
    bool public initialized = false;

    // epoch
    uint256 public startTime;
    uint256 public epoch = 0;
    uint256 public epochSupplyContractionLeft = 0;
    
    // core components
    address public fang;
    address public bfang;
    address public gfang;

    address public masonry;
    address public fangOracle;

    // price
    uint256 public fangPriceOne;
    uint256 public fangPriceCeiling;

    uint256 public seigniorageSaved;

    uint256[] public supplyTiers;
    uint256[] public maxExpansionTiers;

    uint256 public maxSupplyExpansionPercent;
    uint256 public bondDepletionFloorPercent;
    uint256 public seigniorageExpansionFloorPercent;
    uint256 public maxSupplyContractionPercent;
    uint256 public maxDebtRatioPercent;

    // 14 first epochs (0.5 week) with 4.5% expansion regardless of FANG price
    uint256 public bootstrapEpochs;
    uint256 public bootstrapSupplyExpansionPercent;

    /* =================== Added variables =================== */
    uint256 public previousEpochFangPrice;
    uint256 public maxDiscountRate; // when purchasing bond
    uint256 public maxPremiumRate;  // when redeeming bond
    uint256 public discountPercent;
    uint256 public premiumThreshold;
    uint256 public premiumPercent;
    uint256 public mintingFactorForPayingDebt; // print extra FANG during debt phase

    address public daoFund;
    uint256 public daoFundSharedPercent;

    //=================================================//

    address public devFund;
    uint256 public devFundSharedPercent;
    address public teamFund;
    uint256 public teamFundSharedPercent;

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

    event Initialized(address indexed executor, uint256 at);
    event BurnedBonds(address indexed from, uint256 bondAmount);
    event RedeemedBonds(address indexed from, uint256 fangAmount, uint256 bondAmount);
    event BoughtBonds(address indexed from, uint256 fangAmount, uint256 bondAmount);
    event TreasuryFunded(uint256 timestamp, uint256 seigniorage);
    event MasonryFunded(uint256 timestamp, uint256 seigniorage);
    event DaoFundFunded(uint256 timestamp, uint256 seigniorage);
    event DevFundFunded(uint256 timestamp, uint256 seigniorage);
    event TeamFundFunded(uint256 timestamp, uint256 seigniorage);

    /* =================== Modifier =================== */

    modifier checkCondition {
        require(block.timestamp >= startTime, "Treasury: not started yet");

        _;
    }

    modifier checkEpoch {
        require(block.timestamp >= nextEpochPoint(), "Treasury: not opened yet");

        _;

        epoch = epoch.add(1);
        epochSupplyContractionLeft = (getFangPrice() > fangPriceCeiling) ? 0 : getFangCirculatingSupply().mul(maxSupplyContractionPercent).div(BASIS_DIVISOR);
    }

    modifier checkOperator {
        require(
                IBasisAsset(fang).operator() == address(this) &&
                IBasisAsset(bfang).operator() == address(this) &&
                IBasisAsset(gfang).operator() == address(this) &&
                Operator(masonry).operator() == address(this),
            "Treasury: need more permission"
        );

        _;
    }

    modifier notInitialized {
        require(!initialized, "Treasury: already initialized");

        _;
    }

    /* ========== VIEW FUNCTIONS ========== */

    function isInitialized() public view returns (bool) {
        return initialized;
    }

    // epoch
    function nextEpochPoint() public view returns (uint256) {
        return startTime.add(epoch.mul(PERIOD));
    }

    // oracle
    function getFangPrice() public view returns (uint256 fangPrice) {
        try IOracle(fangOracle).consult(fang, 1e18) returns (uint256 price) {
            return uint256(price);
        } catch {
            revert("Treasury: failed to consult FANG price from the oracle");
        }
    }

    function getFangUpdatedPrice() public view returns (uint256 _fangPrice) {
        try IOracle(fangOracle).twap(fang, 1e18) returns (uint256 price) {
            return uint256(price);
        } catch {
            revert("Treasury: failed to consult FANG price from the oracle");
        }
    }

    // budget
    function getReserve() public view returns (uint256) {
        return seigniorageSaved;
    }

    function getBurnableFangLeft() public view returns (uint256 _burnableFangLeft) {
        uint256 _fangPrice = getFangPrice();
        if (_fangPrice <= fangPriceOne) {
            uint256 _fangSupply = getFangCirculatingSupply();
            uint256 _bondMaxSupply = _fangSupply.mul(maxDebtRatioPercent).div(BASIS_DIVISOR);
            uint256 _bondSupply = IERC20(bfang).totalSupply();
            if (_bondMaxSupply > _bondSupply) {
                uint256 _maxMintableBond = _bondMaxSupply.sub(_bondSupply);
                uint256 _maxBurnableFang = _maxMintableBond.mul(_fangPrice).div(1e18);
                _burnableFangLeft = Math.min(epochSupplyContractionLeft, _maxBurnableFang);
            }
        }
    }

    function getRedeemableBonds() public view returns (uint256 _redeemableBonds) {
        uint256 _fangPrice = getFangPrice();
        if (_fangPrice > fangPriceCeiling) {
            uint256 _totalFang = IERC20(fang).balanceOf(address(this));
            uint256 _rate = getBondPremiumRate();
            if (_rate > 0) {
                _redeemableBonds = _totalFang.mul(1e18).div(_rate);
            }
        }
    }

    function getBondDiscountRate() public view returns (uint256 _rate) {
        uint256 _fangPrice = getFangPrice();
        if (_fangPrice <= fangPriceOne) {
            if (discountPercent == 0) {
                // no discount
                _rate = fangPriceOne;
            } else {
                uint256 _bondAmount = fangPriceOne.mul(1e18).div(_fangPrice); // to burn 1 FANG
                uint256 _discountAmount = _bondAmount.sub(fangPriceOne).mul(discountPercent).div(BASIS_DIVISOR);
                _rate = fangPriceOne.add(_discountAmount);
                if (maxDiscountRate > 0 && _rate > maxDiscountRate) {
                    _rate = maxDiscountRate;
                }
            }
        }
    }

    function getBondPremiumRate() public view returns (uint256 _rate) {
        uint256 _fangPrice = getFangPrice();
        if (_fangPrice > fangPriceCeiling) {
            uint256 _fangPricePremiumThreshold = fangPriceOne.mul(premiumThreshold).div(100);
            if (_fangPrice >= _fangPricePremiumThreshold) {
                //Price > 1.10
                uint256 _premiumAmount = _fangPrice.sub(fangPriceOne).mul(premiumPercent).div(BASIS_DIVISOR);
                _rate = fangPriceOne.add(_premiumAmount);
                if (maxPremiumRate > 0 && _rate > maxPremiumRate) {
                    _rate = maxPremiumRate;
                }
            } else {
                // no premium bonus
                _rate = fangPriceOne;
            }
        }
    }

    /* ========== GOVERNANCE ========== */

    function initialize(
        address _fang,
        address _bfang,
        address _gfang,
        address _fangOracle,
        address _masonry,
        uint256 _startTime
    ) public notInitialized onlyOperator {
        fang = _fang;
        bfang = _bfang;
        gfang = _gfang;
        fangOracle = _fangOracle;
        masonry = _masonry;
        startTime = _startTime;

        fangPriceOne = 10 ** 18;
        // fangPriceCeiling = 1000300000000000000; // 1.003 as its stable pool
        fangPriceCeiling = fangPriceOne.mul(101).div(100); // even if its stable we aim to get 1.01

        // Dynamic max expansion percent
        supplyTiers = [0 ether, 1 ether, 2 ether, 3 ether, 4 ether, 5 ether, 6 ether];
        maxExpansionTiers = [110000, 90000, 80000, 70000, 60000, 50000, 20000]; // 0.11%, 0.09%, 0.08%, 0.07%, 0.06%, 0.05%, 0.02%

        maxSupplyExpansionPercent = 150000; // 0.15%

        bondDepletionFloorPercent = BASIS_DIVISOR; // 100% of Bond supply for depletion floor
        seigniorageExpansionFloorPercent = 35000000; // At least 35% of expansion reserved for masonry
        maxSupplyContractionPercent = 10000000; // Upto 10.0% supply for contraction (to burn FANG and mint bfang)
        maxDebtRatioPercent = 35000000; // Upto 35% supply of bfang to purchase

        premiumThreshold = 110; // BASIS IS 100
        premiumPercent = 70000000; // (70%)

        // First 12 epochs with 1.5% expansion
        bootstrapEpochs = 12;
        bootstrapSupplyExpansionPercent = 150000; // 0.15%

        // set seigniorageSaved to it's balance
        seigniorageSaved = IERC20(fang).balanceOf(address(this));

        initialized = true;
        emit Initialized(msg.sender, block.number);
    }

    function setOperator(address _operator) external onlyOperator {
        transferOperator(_operator);
    }

    function renounceOperator() external onlyOperator {
        _renounceOperator();
    }

    function setMasonry(address _masonry) external onlyOperator {
        masonry = _masonry;
    }

    function setFangOracle(address _fangOracle) external onlyOperator {
        fangOracle = _fangOracle;
    }

    function setFangPriceCeiling(uint256 _fangPriceCeiling) external onlyOperator {
        require(_fangPriceCeiling >= fangPriceOne && _fangPriceCeiling <= fangPriceOne.mul(120).div(100), "out of range"); // [$1.0, $1.2]
        fangPriceCeiling = _fangPriceCeiling;
    }

    function setMaxSupplyExpansionPercents(uint256 _maxSupplyExpansionPercent) external onlyOperator {
        require(_maxSupplyExpansionPercent >= 10 && _maxSupplyExpansionPercent <= 10000000, "_maxSupplyExpansionPercent: out of range"); // [0.00001%, 10%]
        maxSupplyExpansionPercent = _maxSupplyExpansionPercent;
    }
    // =================== ALTER THE NUMBERS IN LOGIC!!!! =================== //
    function setSupplyTiersEntry(uint8 _index, uint256 _value) external onlyOperator returns (bool) {
        require(_index >= 0, "Index has to be higher than 0");
        require(_index < 7, "Index has to be lower than count of tiers");
        if (_index > 0) {
            require(_value > supplyTiers[_index - 1]);
        }
        if (_index < 6) {
            require(_value < supplyTiers[_index + 1]);
        }
        supplyTiers[_index] = _value;
        return true;
    }

    function setMaxExpansionTiersEntry(uint8 _index, uint256 _value) external onlyOperator returns (bool) {
        require(_index >= 0, "Index has to be higher than 0");
        require(_index < 7, "Index has to be lower than count of tiers");
        require(_value >= 10 && _value <= 10000000, "_value: out of range"); // [0.00001%, 10%]
        maxExpansionTiers[_index] = _value;
        return true;
    }

    function setBondDepletionFloorPercent(uint256 _bondDepletionFloorPercent) external onlyOperator {
        require(_bondDepletionFloorPercent >= 500 && _bondDepletionFloorPercent <= BASIS_DIVISOR, "out of range"); // [0.0005%, 100%]
        bondDepletionFloorPercent = _bondDepletionFloorPercent;
    }

    function setMaxSupplyContractionPercent(uint256 _maxSupplyContractionPercent) external onlyOperator {
        require(_maxSupplyContractionPercent >= 100 && _maxSupplyContractionPercent <= 15000000, "out of range"); // [0.0001%, 15%]
        maxSupplyContractionPercent = _maxSupplyContractionPercent;
    }

    function setMaxDebtRatioPercent(uint256 _maxDebtRatioPercent) external onlyOperator {
        require(_maxDebtRatioPercent >= 1000 && _maxDebtRatioPercent <= BASIS_DIVISOR, "out of range"); // [0.001%, 100%]
        maxDebtRatioPercent = _maxDebtRatioPercent;
    }

    function setBootstrap(uint256 _bootstrapEpochs, uint256 _bootstrapSupplyExpansionPercent) external onlyOperator {
        require(_bootstrapEpochs <= 1200, "_bootstrapEpochs: out of range"); // <= 10 month
        require(_bootstrapSupplyExpansionPercent >= 100 && _bootstrapSupplyExpansionPercent <= 10000000, "_bootstrapSupplyExpansionPercent: out of range"); // [0.0001%, 10%]
        bootstrapEpochs = _bootstrapEpochs;
        bootstrapSupplyExpansionPercent = _bootstrapSupplyExpansionPercent;
    }
    //======================================================================
    function setExtraFunds(
        address _daoFund,
        uint256 _daoFundSharedPercent,
        address _devFund,
        uint256 _devFundSharedPercent,
        address _teamFund,
        uint256 _teamFundSharedPercent
    ) external onlyOperator {
        require(_daoFund != address(0), "zero");
        require(_daoFundSharedPercent <= 15000000, "out of range");
        require(_devFund != address(0), "zero");
        require(_devFundSharedPercent <= 3500000, "out of range");
        require(_teamFund != address(0), "zero");
        require(_teamFundSharedPercent <= 5500000, "out of range");

        daoFund = _daoFund;
        daoFundSharedPercent = _daoFundSharedPercent;
        devFund = _devFund;
        devFundSharedPercent = _devFundSharedPercent;
        teamFund = _teamFund;
        teamFundSharedPercent = _teamFundSharedPercent;
    }

    function setMaxDiscountRate(uint256 _maxDiscountRate) external onlyOperator {
        require(_maxDiscountRate <= 200000000, "_maxDiscountRate is over 200%");
        maxDiscountRate = _maxDiscountRate;
    }

    function setMaxPremiumRate(uint256 _maxPremiumRate) external onlyOperator {
        require(_maxPremiumRate <= 200000000, "_maxPremiumRate is over 200%");
        maxPremiumRate = _maxPremiumRate;
    }

    function setDiscountPercent(uint256 _discountPercent) external onlyOperator {
        require(_discountPercent <= 200000000, "_discountPercent is over 200%");
        discountPercent = _discountPercent;
    }

    function setPremiumThreshold(uint256 _premiumThreshold) external onlyOperator {
        require(_premiumThreshold >= fangPriceCeiling, "_premiumThreshold exceeds fangPriceCeiling");
        require(_premiumThreshold <= 150, "_premiumThreshold is higher than 1.5");
        premiumThreshold = _premiumThreshold;
    }

    function setPremiumPercent(uint256 _premiumPercent) external onlyOperator {
        require(_premiumPercent <= 200000000, "_premiumPercent is over 200%");
        premiumPercent = _premiumPercent;
    }

    function setMintingFactorForPayingDebt(uint256 _mintingFactorForPayingDebt) external onlyOperator {
        require(_mintingFactorForPayingDebt >= BASIS_DIVISOR && _mintingFactorForPayingDebt <= 200000000, "_mintingFactorForPayingDebt: out of range"); // [100%, 200%]
        mintingFactorForPayingDebt = _mintingFactorForPayingDebt;
    }

    /* ========== MUTABLE FUNCTIONS ========== */

    function _updateFangPrice() internal {
        try IOracle(fangOracle).update() {} catch {}
    }

    function getFangCirculatingSupply() public view returns (uint256) {
        IERC20 fangErc20 = IERC20(fang);
        uint256 totalSupply = fangErc20.totalSupply();
        return totalSupply;
    }

    function buyBonds(uint256 _fangAmount, uint256 targetPrice) external onlyOneBlock checkCondition checkOperator {
        require(_fangAmount > 0, "Treasury: cannot purchase bonds with zero amount");

        uint256 fangPrice = getFangPrice();
        require(fangPrice == targetPrice, "Treasury: FANG price moved");
        require(
            fangPrice < fangPriceOne, // price < $1
            "Treasury: fangPrice not eligible for bond purchase"
        );

        require(_fangAmount <= epochSupplyContractionLeft, "Treasury: not enough bond left to purchase");

        uint256 _rate = getBondDiscountRate();
        require(_rate > 0, "Treasury: invalid bond rate");

        uint256 _bondAmount = _fangAmount.mul(_rate).div(1e18);
        uint256 fangSupply = getFangCirculatingSupply();
        uint256 newBondSupply = IERC20(bfang).totalSupply().add(_bondAmount);
        require(newBondSupply <= fangSupply.mul(maxDebtRatioPercent).div(BASIS_DIVISOR), "over max debt ratio");

        IBasisAsset(fang).burnFrom(msg.sender, _fangAmount);
        IBasisAsset(bfang).mint(msg.sender, _bondAmount);

        epochSupplyContractionLeft = epochSupplyContractionLeft.sub(_fangAmount);
        _updateFangPrice();

        emit BoughtBonds(msg.sender, _fangAmount, _bondAmount);
    }

    function redeemBonds(uint256 _bondAmount, uint256 targetPrice) external onlyOneBlock checkCondition checkOperator {
        require(_bondAmount > 0, "Treasury: cannot redeem bonds with zero amount");

        uint256 fangPrice = getFangPrice();
        require(fangPrice == targetPrice, "Treasury: FANG price moved");
        require(
            fangPrice > fangPriceCeiling, // price > $1.01
            "Treasury: fangPrice not eligible for bond purchase"
        );

        uint256 _rate = getBondPremiumRate();
        require(_rate > 0, "Treasury: invalid bond rate");

        uint256 _fangAmount = _bondAmount.mul(_rate).div(1e18);
        require(IERC20(fang).balanceOf(address(this)) >= _fangAmount, "Treasury: treasury has no more budget");

        seigniorageSaved = seigniorageSaved.sub(Math.min(seigniorageSaved, _fangAmount));

        IBasisAsset(bfang).burnFrom(msg.sender, _bondAmount);
        // IERC20(fang).safeTransfer(msg.sender, _fangAmount);

        _updateFangPrice();

        emit RedeemedBonds(msg.sender, _fangAmount, _bondAmount);
    }

    function _sendToMasonry(uint256 _amount) internal {
        IBasisAsset(fang).mint(address(this), _amount);

        uint256 _daoFundSharedAmount = 0;
        if (daoFundSharedPercent > 0) {
            _daoFundSharedAmount = _amount.mul(daoFundSharedPercent).div(BASIS_DIVISOR);
            IERC20(fang).transfer(daoFund, _daoFundSharedAmount);
            emit DaoFundFunded(block.timestamp, _daoFundSharedAmount);
        }

        uint256 _devFundSharedAmount = 0;
        if (devFundSharedPercent > 0) {
            _devFundSharedAmount = _amount.mul(devFundSharedPercent).div(BASIS_DIVISOR);
            IERC20(fang).transfer(devFund, _devFundSharedAmount);
            emit DevFundFunded(block.timestamp, _devFundSharedAmount);
        }

        uint256 _teamFundSharedAmount = 0;
        if (teamFundSharedPercent > 0) {
            _teamFundSharedAmount = _amount.mul(teamFundSharedPercent).div(BASIS_DIVISOR);
            IERC20(fang).transfer(teamFund, _teamFundSharedAmount);
            emit TeamFundFunded(block.timestamp, _teamFundSharedAmount);
        }

        _amount = _amount.sub(_daoFundSharedAmount).sub(_devFundSharedAmount).sub(_teamFundSharedAmount);

        IERC20(fang).safeApprove(masonry, 0);
        IERC20(fang).safeApprove(masonry, _amount);
        IMasonry(masonry).allocateSeigniorage(_amount);
        emit MasonryFunded(block.timestamp, _amount);
    }

    function _calculateMaxSupplyExpansionPercent(uint256 _fangSupply) internal returns (uint256) {
        for (uint8 tierId = 6; tierId >= 0; --tierId) {
            if (_fangSupply >= supplyTiers[tierId]) {
                maxSupplyExpansionPercent = maxExpansionTiers[tierId];
                break;
            }
        }
        return maxSupplyExpansionPercent;
    }

    function allocateSeigniorage() external onlyOneBlock checkCondition checkEpoch checkOperator {
        _updateFangPrice();
        previousEpochFangPrice = getFangPrice();
        uint256 fangSupply = getFangCirculatingSupply().sub(seigniorageSaved);
        if (epoch < bootstrapEpochs) {
            // 14 first epochs with 6% expansion
            _sendToMasonry(fangSupply.mul(bootstrapSupplyExpansionPercent).div(BASIS_DIVISOR));
        } else {
            if (previousEpochFangPrice > fangPriceCeiling) {
                // Expansion ($FANG Price > 1 $FTM): there is some seigniorage to be allocated
                uint256 bondSupply = IERC20(bfang).totalSupply();
                uint256 _percentage = previousEpochFangPrice.sub(fangPriceOne);
                uint256 _savedForBond;
                uint256 _savedForMasonry;
                uint256 _mse = _calculateMaxSupplyExpansionPercent(fangSupply).mul(1e10);
                if (_percentage > _mse) {
                    _percentage = _mse;
                }
                if (seigniorageSaved >= bondSupply.mul(bondDepletionFloorPercent).div(BASIS_DIVISOR)) {
                    // saved enough to pay debt, mint as usual rate
                    _savedForMasonry = fangSupply.mul(_percentage).div(1e18);
                } else {
                    // have not saved enough to pay debt, mint more
                    uint256 _seigniorage = fangSupply.mul(_percentage).div(1e18);
                    _savedForMasonry = _seigniorage.mul(seigniorageExpansionFloorPercent).div(BASIS_DIVISOR);
                    _savedForBond = _seigniorage.sub(_savedForMasonry);
                    if (mintingFactorForPayingDebt > 0) {
                        _savedForBond = _savedForBond.mul(mintingFactorForPayingDebt).div(BASIS_DIVISOR);
                    }
                }
                if (_savedForMasonry > 0) {
                    _sendToMasonry(_savedForMasonry);
                }
                if (_savedForBond > 0) {
                    seigniorageSaved = seigniorageSaved.add(_savedForBond);
                    IBasisAsset(fang).mint(address(this), _savedForBond);
                    emit TreasuryFunded(block.timestamp, _savedForBond);
                }
            }
        }
    }
    //===================================================================================================================================

    function governanceRecoverUnsupported(
        IERC20 _token,
        uint256 _amount,
        address _to
    ) external onlyOperator {
        // do not allow to drain core tokens
        require(address(_token) != address(fang), "fang");
        require(address(_token) != address(bfang), "bond");
        require(address(_token) != address(gfang), "share");
        _token.safeTransfer(_to, _amount);
    }

    function masonrySetOperator(address _operator) external onlyOperator {
        IMasonry(masonry).setOperator(_operator);
    }

    function masonrySetLockUp(uint256 _withdrawLockupEpochs, uint256 _rewardLockupEpochs) external onlyOperator {
        IMasonry(masonry).setLockUp(_withdrawLockupEpochs, _rewardLockupEpochs);
    }

    function masonryAllocateSeigniorage(uint256 amount) external onlyOperator {
        IMasonry(masonry).allocateSeigniorage(amount);
    }

    function masonryGovernanceRecoverUnsupported(
        address _token,
        uint256 _amount,
        address _to
    ) external onlyOperator {
        IMasonry(masonry).governanceRecoverUnsupported(_token, _amount, _to);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

contract ContractGuard {
    mapping(uint256 => mapping(address => bool)) private _status;

    function checkSameOriginReentranted() internal view returns (bool) {
        return _status[block.number][tx.origin];
    }

    function checkSameSenderReentranted() internal view returns (bool) {
        return _status[block.number][msg.sender];
    }

    modifier onlyOneBlock() {
        require(!checkSameOriginReentranted(), "ContractGuard: one block, one function");
        require(!checkSameSenderReentranted(), "ContractGuard: one block, one function");

        _;

        _status[block.number][tx.origin] = true;
        _status[block.number][msg.sender] = true;
    }
}

// SPDX-License-Identifier: BUSL-1.1

pragma solidity ^0.8.0;

import "./interfaces/IWETH.sol";
import "./interfaces/IUniswapV2Pair.sol";
import "./interfaces/IShadowRouter.sol";
import "./interfaces/IFangRedeem.sol";
import "./lib/TransferHelper.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

/**************************************************************************************************************************************************

 /$$$$$$$$                                 /$$$$$$$$ /$$                                                  
| $$_____/                                | $$_____/|__/                                                  
| $$    /$$$$$$  /$$$$$$$   /$$$$$$       | $$       /$$ /$$$$$$$   /$$$$$$  /$$$$$$$   /$$$$$$$  /$$$$$$ 
| $$$$$|____  $$| $$__  $$ /$$__  $$      | $$$$$   | $$| $$__  $$ |____  $$| $$__  $$ /$$_____/ /$$__  $$
| $$__/ /$$$$$$$| $$  \ $$| $$  \ $$      | $$__/   | $$| $$  \ $$  /$$$$$$$| $$  \ $$| $$      | $$$$$$$$
| $$   /$$__  $$| $$  | $$| $$  | $$      | $$      | $$| $$  | $$ /$$__  $$| $$  | $$| $$      | $$_____/
| $$  |  $$$$$$$| $$  | $$|  $$$$$$$      | $$      | $$| $$  | $$|  $$$$$$$| $$  | $$|  $$$$$$$|  $$$$$$$
|__/   \_______/|__/  |__/ \____  $$      |__/      |__/|__/  |__/ \_______/|__/  |__/ \_______/ \_______/
                           /$$  \ $$                                                                      
                          |  $$$$$$/                                                                      
                           \______/                                                                       
                                                                                                                                                    
#### Website: https://fang.finance/
#### Author: kell

**************************************************************************************************************************************************/

contract ZapperFangNestBlackhole is Ownable {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

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

    address public constant SHADOW_ROUTER = 0xbFAe8E87053309fDe07ab3cA5f4B5345f8e3058f;
    address public constant WETH_TOKEN = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address public constant FANG_TOKEN = 0x9b2Ebd63425978A1F3462e1538B497B5ba1d7180;
    address public constant FANG_LP_TOKEN = 0x6509f770B83856Ac51613AEe73D1E7bFaD032784;
    address public constant FANG_REDEEM = 0x0000000000000000000000000000000000000000;

    struct LiquidityPair {
        address _token0;
        address _token1;
        uint256 _amountToken0;
        uint256 _amountToken1;
        uint256 _liqTokenAmt;
    }

    struct FunctionArgs {
        address _LP;
        address _in;
        address _out;
        address _recipient;
        address _routerAddr;
        address _token;
        uint256 _amount;
        
        uint256 _otherAmt;
        uint256 _swapAmt;
    }

    // Fang address here
    constructor() Ownable() {}

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

    // @_in - Token we want to throw in
    // @amount - amount of our _in
    // @minAmountOfLp - will be calculated on UI including slippage set by user
    function zapInToken(address _in, uint256 amount, address _recipient, uint256 minAmountOfLp) external {
        // From an ERC20 to an LP token, through specified router, going through base asset if necessary
        // 1. check if its authorized token
        require(_in == FANG_TOKEN, "Only Fang tokens accepted");

        // 2. transfer tokens from sender to this contract
        IERC20(_in).safeTransferFrom(msg.sender, address(this), amount);
        // 2.1 redeem fang
        _approveTokenIfNeeded(FANG_TOKEN, FANG_REDEEM);
        IFangRedeem(FANG_REDEEM).redeemFang(amount);
        amount = IERC20(WETH_TOKEN).balanceOf(address(this));
        // 2.2 set _in to wrapped eth
        _in = WETH_TOKEN;

        // 3. approve router to spend tokens
        _approveTokenIfNeeded(_in, SHADOW_ROUTER);

        // 4. swap part of _in for other token
        address other = (_in == WETH_TOKEN || _in == address(0)) ? FANG_TOKEN : WETH_TOKEN;
        (uint256 amountOfTokenIn, uint256 amountToSwapForOtherToken, uint256 amountOtherForLiquidityEstimate) = getTokenAmountsForLiquidity(_in, amount);

        // 4.3 approve router to spend other token (done)
        _approveTokenIfNeeded(other, SHADOW_ROUTER);

        // 4.4 swap _in for other token
        uint256 otherAmount = _swap(_in, amountToSwapForOtherToken, other, address(this));
        require(otherAmount >= amountOtherForLiquidityEstimate, "amount smaller than estimate");

        // get quoteaddliquidity
        (uint256 amountInToAdd, uint256 amountOtherToAdd, ) = IShadowRouter(SHADOW_ROUTER).quoteAddLiquidity(_in, other, true, amountOfTokenIn, amountOtherForLiquidityEstimate);
        // require(liquidity >= minAmountOfLp, "lp amount too small");

        address recipient = _recipient;

        // 5. add liquidity
        ( , , uint liquidity) = IShadowRouter(SHADOW_ROUTER).addLiquidity(
            _in,
            other,
            true,
            amountInToAdd,
            amountOtherToAdd,
            0, // can be 0 because we already have a require for minAmountOfLp
            0, // can be 0 because we already have a require for minAmountOfLp
            recipient, 
            block.timestamp
        );

        require(liquidity >= minAmountOfLp, "lp amount too small");

        // 6. distribute dust
        retrieveDust(_in, recipient);
        retrieveDust(other, recipient);
    }
   
    function _swap(address _from, uint amount, address _to, address recipient) private returns (uint) {
        IShadowRouter.route[] memory routes = new IShadowRouter.route[](1);
        routes[0] = IShadowRouter.route({
            from: _from,
            to: _to,
            stable: true
        });

        uint256 minAmountOut = _estimateSwap(_from, amount, _to);

        uint[] memory amounts = IShadowRouter(SHADOW_ROUTER).swapExactTokensForTokens(
            amount,
            minAmountOut, // Use calculated minimum amount instead of 0
            routes,
            recipient,
            block.timestamp
        );

        require(amounts[amounts.length-1] >= minAmountOut, "amount smaller than estimate");
        return amounts[amounts.length - 1];
    }

    // @_in - Token we want to throw in
    // @amount - amount of our _in
    // @out - address of LP we are going to get
    function estimateZapIn(address _in, uint256 amount) public view returns (uint256, uint256, uint256, uint256) {
        address other = (_in == WETH_TOKEN || _in == address(0)) ? FANG_TOKEN : WETH_TOKEN;
        (uint256 amountOfTokenIn, uint256 amountToSwapForOtherToken, uint256 amountOtherForLiquidityEstimate) = getTokenAmountsForLiquidity(_in, amount);

        if (_in == IUniswapV2Pair(FANG_LP_TOKEN).token0()) {
            (uint256 amountIn, uint256 amountOther, uint256 liquidity) = IShadowRouter(SHADOW_ROUTER).quoteAddLiquidity(_in, other, true, amountOfTokenIn, amountOtherForLiquidityEstimate);
            return (amountIn, amountOther, amountToSwapForOtherToken, liquidity);
        } else {
            (uint256 amountOther, uint256 amountIn, uint256 liquidity) = IShadowRouter(SHADOW_ROUTER).quoteAddLiquidity(other, _in, true, amountOtherForLiquidityEstimate, amountOfTokenIn);
            return (amountOther, amountIn, amountToSwapForOtherToken, liquidity);
        }
    }

    function getTokenAmountsForLiquidity(address _in, uint256 amount) public view returns(uint256, uint256, uint256) {
        uint256 poolAmountWrappedEth = IUniswapV2Pair(WETH_TOKEN).balanceOf(FANG_LP_TOKEN);
        uint256 poolAmountFang = IUniswapV2Pair(FANG_TOKEN).balanceOf(FANG_LP_TOKEN);

        uint256 poolRatioOfEth = poolAmountWrappedEth.mul(1e18).div(poolAmountFang.add(poolAmountWrappedEth));
        uint256 poolRatioOfFang = poolAmountFang.mul(1e18).div(poolAmountFang.add(poolAmountWrappedEth));

        address tokenIn = _in;
        bool tokenInIsEth = tokenIn == WETH_TOKEN || tokenIn == address(0);
        
        uint256 _amount = amount;

        uint256 amountOfTokenIn = tokenInIsEth ? _amount.mul(poolRatioOfEth).div(1e18) : _amount.mul(poolRatioOfFang).div(1e18);
        uint256 amountToSwapForOtherToken = _amount.sub(amountOfTokenIn);
        uint256 amountOfOtherTokenForLiquidity = _estimateSwap(tokenIn, amountToSwapForOtherToken, tokenIn == WETH_TOKEN ? FANG_TOKEN : WETH_TOKEN);

        return (amountOfTokenIn, amountToSwapForOtherToken, amountOfOtherTokenForLiquidity);
    }
    
    // @_in - token we want to throw in
    // @amount - amount of our _in
    // @out - token we want to get out
    function _estimateSwap(address _in, uint256 amount, address out) public view returns (uint256) {
        IShadowRouter router = IShadowRouter(SHADOW_ROUTER);
        IShadowRouter.route[] memory routes = new IShadowRouter.route[](1);
        routes[0] = IShadowRouter.route({
            from: _in,
            to: out,
            stable: true
        });

        uint256[] memory amounts = router.getAmountsOut(amount, routes);
        return amounts[amounts.length - 1];
    }
    /* ========== Private Functions ========== */

    function _approveTokenIfNeeded(address token, address router) private {
        if (IERC20(token).allowance(address(this), router) == 0) {
            IERC20(token).safeApprove(router, type(uint256).max);
        }
    }

    function retrieveDust(address token, address recipient) private {
        if (token == address(0)) {
            payable(recipient).transfer(address(this).balance);
            return;
        }
        IERC20(token).transfer(recipient, IERC20(token).balanceOf(address(this)));
    }

    /* ========== RESTRICTED FUNCTIONS ========== */
    function withdraw(address token) external onlyOwner {
        if (token == address(0)) {
            payable(owner()).transfer(address(this).balance);
            return;
        }
        IERC20(token).transfer(owner(), IERC20(token).balanceOf(address(this)));
    }

    // add receive function
    receive() external payable {}
}

// SPDX-License-Identifier: BUSL-1.1

pragma solidity ^0.8.0;

import "./interfaces/IWETH.sol";
import "./shadow/interfaces/IPool.sol";
import "./interfaces/IBlackholeRouter.sol";
import "./lib/TransferHelper.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}

/**************************************************************************************************************************************************

 /$$$$$$$$                                 /$$$$$$$$ /$$                                                  
| $$_____/                                | $$_____/|__/                                                  
| $$    /$$$$$$  /$$$$$$$   /$$$$$$       | $$       /$$ /$$$$$$$   /$$$$$$  /$$$$$$$   /$$$$$$$  /$$$$$$ 
| $$$$$|____  $$| $$__  $$ /$$__  $$      | $$$$$   | $$| $$__  $$ |____  $$| $$__  $$ /$$_____/ /$$__  $$
| $$__/ /$$$$$$$| $$  \ $$| $$  \ $$      | $$__/   | $$| $$  \ $$  /$$$$$$$| $$  \ $$| $$      | $$$$$$$$
| $$   /$$__  $$| $$  | $$| $$  | $$      | $$      | $$| $$  | $$ /$$__  $$| $$  | $$| $$      | $$_____/
| $$  |  $$$$$$$| $$  | $$|  $$$$$$$      | $$      | $$| $$  | $$|  $$$$$$$| $$  | $$|  $$$$$$$|  $$$$$$$
|__/   \_______/|__/  |__/ \____  $$      |__/      |__/|__/  |__/ \_______/|__/  |__/ \_______/ \_______/
                           /$$  \ $$                                                                      
                          |  $$$$$$/                                                                      
                           \______/                                                                       
                                                                                                                                                    
#### Website: https://fang.finance/
#### Author: kell

**************************************************************************************************************************************************/

contract ZapperFangV2Blackhole is Ownable {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

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

    address public constant BLACKHOLE_ROUTER = 0xbFAe8E87053309fDe07ab3cA5f4B5345f8e3058f;
    address public constant BLACKHOLE_ROUTER_HELPER = 0xd8377AEa61C4C4d43bF0588956f4E861720803C6;
    address public constant WETH_TOKEN = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address public constant FANG_TOKEN = 0x9b2Ebd63425978A1F3462e1538B497B5ba1d7180;
    address public constant FANG_LP_TOKEN = 0x6509f770B83856Ac51613AEe73D1E7bFaD032784;

    struct LiquidityPair {
        address _token0;
        address _token1;
        uint256 _amountToken0;
        uint256 _amountToken1;
        uint256 _liqTokenAmt;
    }

    struct FunctionArgs {
        address _LP;
        address _in;
        address _out;
        address _recipient;
        address _routerAddr;
        address _token;
        uint256 _amount;
        
        uint256 _otherAmt;
        uint256 _swapAmt;
    }

    // Fang address here
    constructor() Ownable() {}

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

    // @_in - Token we want to throw in
    // @amount - amount of our _in
    // @minAmountOfLp - will be calculated on UI including slippage set by user
    function zapInToken(address _in, uint256 amount, address _recipient, uint256 minAmountOfLp) external payable {
        // From an ERC20 to an LP token, through specified router, going through base asset if necessary
        // 1. check if its authorized token
        require(_in == WETH_TOKEN || _in == FANG_TOKEN || _in == address(0), "Only S, wS or Fang tokens accepted");

        // 2. transfer tokens from sender to this contract
        if (_in != address(0)) {
            IERC20(_in).safeTransferFrom(msg.sender, address(this), amount);
        } else {
            require(msg.value == amount, "Incorrect amount of S sent");
            IWETH(WETH_TOKEN).deposit{value: amount}();
            _in = WETH_TOKEN;
        }

        // 3. approve router to spend tokens
        _approveTokenIfNeeded(_in, BLACKHOLE_ROUTER);

        // 4. swap part of _in for other token
        address other = (_in == WETH_TOKEN || _in == address(0)) ? FANG_TOKEN : WETH_TOKEN;
        (uint256 amountOfTokenIn, uint256 amountToSwapForOtherToken, uint256 amountOtherForLiquidityEstimate) = getTokenAmountsForLiquidity(_in, amount);

        // 4.3 approve router to spend other token (done)
        _approveTokenIfNeeded(other, BLACKHOLE_ROUTER);

        // 4.4 swap _in for other token
        uint256 otherAmount = _swap(_in, amountToSwapForOtherToken, other, address(this));
        require(otherAmount >= amountOtherForLiquidityEstimate, "amount smaller than estimate");

        // get quoteaddliquidity
        (uint256 amountInToAdd, uint256 amountOtherToAdd, ) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteAddLiquidity(_in, other, true, amountOfTokenIn, amountOtherForLiquidityEstimate);
        // require(liquidity >= minAmountOfLp, "lp amount too small");

        address recipient = _recipient;

        // 5. add liquidity
        ( , , uint liquidity) = IBlackholeRouter(BLACKHOLE_ROUTER).addLiquidity(
            _in,
            other,
            true,
            amountInToAdd,
            amountOtherToAdd,
            1, // can be 0 because we already have a require for minAmountOfLp
            1, // can be 0 because we already have a require for minAmountOfLp
            recipient, 
            block.timestamp
        );

        // require(liquidity >= minAmountOfLp, "lp amount too small");

        // 6. distribute dust
        retrieveDust(_in, recipient);
        retrieveDust(other, recipient);
    }

    // from an LP token to desired token
    // @in - LP we want to throw in
    // @amount - amount of our LP
    // @out - token we want to get
    function zapOutToToken(uint256 amount, address out, address recipient, uint256 minAmountToken) external {
        require(out == WETH_TOKEN || out == FANG_TOKEN || out == address(0), "Only S, wS or Fang tokens accepted");

        FunctionArgs memory args;
        LiquidityPair memory pair;

        args._amount = amount;
        args._out = out == address(0) ? WETH_TOKEN : out;
        args._recipient = recipient;
        
        args._in = FANG_LP_TOKEN;

        IERC20(args._in).safeTransferFrom(msg.sender, address(this), args._amount);
        _approveTokenIfNeeded(args._in, BLACKHOLE_ROUTER);

        pair._token0 = IPool(args._in).token0();
        pair._token1 = IPool(args._in).token1();

        _approveTokenIfNeeded(pair._token0, BLACKHOLE_ROUTER);
        _approveTokenIfNeeded(pair._token1, BLACKHOLE_ROUTER);

        (pair._amountToken0, pair._amountToken1) = IBlackholeRouter(BLACKHOLE_ROUTER).removeLiquidity(pair._token0, pair._token1, true, args._amount, 0, 0, address(this), block.timestamp);
        if (pair._token0 != args._out) {
            pair._amountToken0 = _swap(pair._token0, pair._amountToken0, args._out, address(this));
        }
        if (pair._token1 != args._out) {
            pair._amountToken1 = _swap(pair._token1, pair._amountToken1, args._out, address(this));
        }
        require (pair._amountToken0.add(pair._amountToken1) >= minAmountToken, "amt < minAmountToken");

        if (out == address(0)) {
            IWETH(WETH_TOKEN).withdraw(pair._amountToken0.add(pair._amountToken1));
            payable(recipient).transfer(pair._amountToken0.add(pair._amountToken1));
        } else {
            IERC20(args._out).safeTransfer(args._recipient, pair._amountToken0.add(pair._amountToken1));
        }
    }
   
    function _swap(address _from, uint amount, address _to, address recipient) private returns (uint) {
        IBlackholeRouter.route[] memory routes = new IBlackholeRouter.route[](1);
        routes[0] = IBlackholeRouter.route({
            pair: FANG_LP_TOKEN,
            from: _from,
            to: _to,
            stable: true,
            concentrated: false,
            receiver: recipient
        });

        uint256 minAmountOut = _estimateSwap(_from, amount, _to);

        uint[] memory amounts = IBlackholeRouter(BLACKHOLE_ROUTER).swapExactTokensForTokens(
            amount,
            minAmountOut, // Use calculated minimum amount instead of 0
            routes,
            recipient,
            block.timestamp
        );

        require(amounts[amounts.length-1] >= minAmountOut, "amount smaller than estimate");
        return amounts[amounts.length - 1];
    }

    // @_in - Token we want to throw in
    // @amount - amount of our _in
    // @out - address of LP we are going to get

    function estimateZapIn(address _in, uint256 amount) public view returns (uint256, uint256, uint256, uint256) {
        address other = (_in == WETH_TOKEN || _in == address(0)) ? FANG_TOKEN : WETH_TOKEN;
        (uint256 amountOfTokenIn, uint256 amountToSwapForOtherToken, uint256 amountOtherForLiquidityEstimate) = getTokenAmountsForLiquidity(_in, amount);

        if (_in == IPool(FANG_LP_TOKEN).token0()) {
            (uint256 amountIn, uint256 amountOther, uint256 liquidity) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteAddLiquidity(_in, other, true, amountOfTokenIn, amountOtherForLiquidityEstimate);
            return (amountIn, amountOther, amountToSwapForOtherToken, liquidity);
        } else {
            (uint256 amountOther, uint256 amountIn, uint256 liquidity) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteAddLiquidity(other, _in, true, amountOtherForLiquidityEstimate, amountOfTokenIn);
            return (amountOther, amountIn, amountToSwapForOtherToken, liquidity);
        }
    }

struct LiquidityCalcContext {
    address tokenIn;
    uint256 amountIn;
    uint256 reserveIn;
    uint256 reserveOut;
    uint256 decimalsIn;
    uint256 decimalsOut;
    uint256 ratio;
    uint256 bestIn;
    uint256 bestOut;
}

function getTokenAmountsForLiquidity(address tokenIn, uint256 amountIn) public view returns (
    uint256 amountOfTokenIn,      // WETH kept
    uint256 amountSwapped,        // WETH swapped to FANG
    uint256 amountOfOtherToken    // resulting FANG
) {
    require(tokenIn != address(0), "Invalid tokenIn");

    IPool pair = IPool(FANG_LP_TOKEN);
    address token0 = pair.token0();
    address token1 = pair.token1();

    bool isInput0 = tokenIn == token0;

    // Load decimals once
    LiquidityCalcContext memory ctx;
    ctx.tokenIn = tokenIn;
    ctx.amountIn = amountIn;
    ctx.decimalsIn = IERC20Metadata(isInput0 ? token0 : token1).decimals();
    ctx.decimalsOut = IERC20Metadata(isInput0 ? token1 : token0).decimals();

    (uint112 reserve0, uint112 reserve1, ) = pair.getReserves();
    ctx.reserveIn = isInput0 ? reserve0 : reserve1;
    ctx.reserveOut = isInput0 ? reserve1 : reserve0;

    // Target ratio required by Solidly stable pool
    ctx.ratio = (ctx.reserveIn * 1e18 / ctx.decimalsIn) * 1e18 / (ctx.reserveOut * 1e18 / ctx.decimalsOut);

    // Binary search to solve: (amountIn - x) / getAmountOut(x) == ratio
    uint256 low = 0;
    uint256 high = ctx.amountIn;

    for (uint256 i = 0; i < 20; i++) {
        uint256 mid = (low + high) / 2;
        uint256 out = pair.getAmountOut(mid, ctx.tokenIn); // returns FANG

        uint256 lhs = (ctx.amountIn - mid) * 1e18;
        uint256 rhs = out * ctx.ratio;

        if (lhs > rhs) {
            low = mid;
        } else {
            ctx.bestIn = ctx.amountIn - mid;
            ctx.bestOut = out;
            high = mid;
        }
    }

    return (ctx.bestIn, ctx.amountIn - ctx.bestIn, ctx.bestOut);
}


     // @ _fromLP - LP we want to throw in
    // @ _to - token we want to get out of our LP
    // @ minAmountToken0, minAmountToken1 - coming from UI (min amount of tokens coming from breaking our LP)
    function estimateZapOut(address _out, uint256 _amount) public view returns (uint256) {
        address token0 = IPool(FANG_LP_TOKEN).token0();
        address token1 = IPool(FANG_LP_TOKEN).token1();

        (uint256 _amountToken0, uint256 _amountToken1) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteRemoveLiquidity(token0, token1, true, _amount);
        if(token0 == _out) { // if eth, need to swap token1
            return _estimateSwap(token1, _amountToken1, _out).add(_amountToken0);
        } else {
            return _estimateSwap(token0, _amountToken0, _out).add(_amountToken1);
        }
    }
    
    // @_in - token we want to throw in
    // @amount - amount of our _in
    // @out - token we want to get out
    function _estimateSwap(address _in, uint256 amount, address out) public view returns (uint256) {
        IBlackholeRouter.route[] memory routes = new IBlackholeRouter.route[](1);
        routes[0] = IBlackholeRouter.route({
            pair: FANG_LP_TOKEN,
            from: _in,
            to: out,
            stable: true,
            concentrated: false,
            receiver: address(this)
        });

        uint256[] memory amounts = IBlackholeRouter(BLACKHOLE_ROUTER_HELPER).getAmountsOut(amount, routes);
        return amounts[amounts.length - 1];
    }
    /* ========== Private Functions ========== */

    function _approveTokenIfNeeded(address token, address router) private {
        if (IERC20(token).allowance(address(this), router) == 0) {
            IERC20(token).safeApprove(router, type(uint256).max);
        }
    }

    function retrieveDust(address token, address recipient) private {
        if (token == address(0)) {
            payable(recipient).transfer(address(this).balance);
            return;
        }
        IERC20(token).transfer(recipient, IERC20(token).balanceOf(address(this)));
    }

    /* ========== RESTRICTED FUNCTIONS ========== */
    function withdraw(address token) external onlyOwner {
        if (token == address(0)) {
            payable(owner()).transfer(address(this).balance);
            return;
        }
        IERC20(token).transfer(owner(), IERC20(token).balanceOf(address(this)));
    }

    // add receive function
    receive() external payable {}
}

// SPDX-License-Identifier: BUSL-1.1

pragma solidity ^0.8.0;

import "./interfaces/IWETH.sol";
import "./interfaces/IUniswapV2Pair.sol";
import "./interfaces/IBlackholeRouter.sol";
import "./lib/TransferHelper.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Context.sol";
import "@openzeppelin/contracts/access/Ownable.sol";

/**************************************************************************************************************************************************

 /$$$$$$$$                                 /$$$$$$$$ /$$                                                  
| $$_____/                                | $$_____/|__/                                                  
| $$    /$$$$$$  /$$$$$$$   /$$$$$$       | $$       /$$ /$$$$$$$   /$$$$$$  /$$$$$$$   /$$$$$$$  /$$$$$$ 
| $$$$$|____  $$| $$__  $$ /$$__  $$      | $$$$$   | $$| $$__  $$ |____  $$| $$__  $$ /$$_____/ /$$__  $$
| $$__/ /$$$$$$$| $$  \ $$| $$  \ $$      | $$__/   | $$| $$  \ $$  /$$$$$$$| $$  \ $$| $$      | $$$$$$$$
| $$   /$$__  $$| $$  | $$| $$  | $$      | $$      | $$| $$  | $$ /$$__  $$| $$  | $$| $$      | $$_____/
| $$  |  $$$$$$$| $$  | $$|  $$$$$$$      | $$      | $$| $$  | $$|  $$$$$$$| $$  | $$|  $$$$$$$|  $$$$$$$
|__/   \_______/|__/  |__/ \____  $$      |__/      |__/|__/  |__/ \_______/|__/  |__/ \_______/ \_______/
                           /$$  \ $$                                                                      
                          |  $$$$$$/                                                                      
                           \______/                                                                       
                                                                                                                                                    
#### Website: https://fang.finance/
#### Author: kell

**************************************************************************************************************************************************/

contract ZapperGFangBlackhole is Ownable {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

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

    address public constant BLACKHOLE_ROUTER = 0xbFAe8E87053309fDe07ab3cA5f4B5345f8e3058f;
    address public constant BLACKHOLE_ROUTER_HELPER = 0xd8377AEa61C4C4d43bF0588956f4E861720803C6;
    address public constant WETH_TOKEN = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
    address public constant GFANG_TOKEN = 0x4CB85e39d5622Af604405077A589c3078F3A59b2;
    address public constant GFANG_LP_TOKEN = 0x7AA0f18126C04c03A7390e15fA60c7054f97aF39;

    struct LiquidityPair {
        address _token0;
        address _token1;
        uint256 _amountToken0;
        uint256 _amountToken1;
        uint256 _liqTokenAmt;
    }

    struct FunctionArgs {
        address _LP;
        address _in;
        address _out;
        address _recipient;
        address _routerAddr;
        address _token;
        uint256 _amount;
        
        uint256 _otherAmt;
        uint256 _swapAmt;
    }

    constructor() Ownable() {}

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

    // @_in - Token we want to throw in
    // @amount - amount of our _in
    // @minAmountOfLp - will be calculated on UI including slippage set by user
    function zapInToken(address _in, uint256 amount, address _recipient, uint256 minAmountOfLp) external payable {
        // From an ERC20 to an LP token, through specified router, going through base asset if necessary
        // 1. check if its authorized token
        require(_in == WETH_TOKEN || _in == GFANG_TOKEN || _in == address(0), "Only S, wS or GFang tokens accepted");

        // 2. transfer tokens from sender to this contract
        if (_in != address(0)) {
            IERC20(_in).safeTransferFrom(msg.sender, address(this), amount);
        } else {
            require(msg.value == amount, "Incorrect amount of S sent");
            IWETH(WETH_TOKEN).deposit{value: amount}();
            _in = WETH_TOKEN;
        }

        // 3. approve router to spend tokens
        _approveTokenIfNeeded(_in, BLACKHOLE_ROUTER);

        // 4. swap part of _in for other token
        address other = (_in == WETH_TOKEN || _in == address(0)) ? GFANG_TOKEN : WETH_TOKEN;
        (uint256 amountOfTokenIn, uint256 amountToSwapForOtherToken, uint256 amountOtherForLiquidityEstimate) = getTokenAmountsForLiquidity(_in, amount);

        // 4.3 approve router to spend other token (done)
        _approveTokenIfNeeded(other, BLACKHOLE_ROUTER);

        // 4.4 swap _in for other token
        uint256 otherAmount = _swap(_in, amountToSwapForOtherToken, other, address(this));
        require(otherAmount >= amountOtherForLiquidityEstimate, "amount smaller than estimate");

        // get quoteaddliquidity
        (uint256 amountInToAdd, uint256 amountOtherToAdd, ) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteAddLiquidity(_in, other, false, amountOfTokenIn, amountOtherForLiquidityEstimate);
        // require(liquidity >= minAmountOfLp, "lp amount too small");

        address recipient = _recipient;

        // 5. add liquidity
        ( , , uint liquidity) = IBlackholeRouter(BLACKHOLE_ROUTER).addLiquidity(
            _in,
            other,
            false,
            amountInToAdd,
            amountOtherToAdd,
            0, // can be 0 because we already have a require for minAmountOfLp
            0, // can be 0 because we already have a require for minAmountOfLp
            recipient, 
            block.timestamp
        );

        require(liquidity >= minAmountOfLp, "lp amount too small");

        // 6. distribute dust
        retrieveDust(_in, recipient);
        retrieveDust(other, recipient);
    }

    // from an LP token to desired token
    // @in - LP we want to throw in
    // @amount - amount of our LP
    // @out - token we want to get
    function zapOutToToken(uint256 amount, address out, address recipient, uint256 minAmountToken) external {
        require(out == WETH_TOKEN || out == GFANG_TOKEN || out == address(0), "Only S, wS or GFang tokens accepted");

        FunctionArgs memory args;
        LiquidityPair memory pair;

        args._amount = amount;
        args._out = out == address(0) ? WETH_TOKEN : out;
        args._recipient = recipient;
        
        args._in = GFANG_LP_TOKEN;

        IERC20(args._in).safeTransferFrom(msg.sender, address(this), args._amount);
        _approveTokenIfNeeded(args._in, BLACKHOLE_ROUTER);

        pair._token0 = IUniswapV2Pair(args._in).token0();
        pair._token1 = IUniswapV2Pair(args._in).token1();

        _approveTokenIfNeeded(pair._token0, BLACKHOLE_ROUTER);
        _approveTokenIfNeeded(pair._token1, BLACKHOLE_ROUTER);

        (pair._amountToken0, pair._amountToken1) = IBlackholeRouter(BLACKHOLE_ROUTER).removeLiquidity(pair._token0, pair._token1, false, args._amount, 0, 0, address(this), block.timestamp);
        if (pair._token0 != args._out) {
            pair._amountToken0 = _swap(pair._token0, pair._amountToken0, args._out, address(this));
        }
        if (pair._token1 != args._out) {
            pair._amountToken1 = _swap(pair._token1, pair._amountToken1, args._out, address(this));
        }
        require (pair._amountToken0.add(pair._amountToken1) >= minAmountToken, "amt < minAmountToken");

        if (out == address(0)) {
            IWETH(WETH_TOKEN).withdraw(pair._amountToken0.add(pair._amountToken1));
            payable(recipient).transfer(pair._amountToken0.add(pair._amountToken1));
        } else {
            IERC20(args._out).safeTransfer(args._recipient, pair._amountToken0.add(pair._amountToken1));
        }
    }
   
    function _swap(address _from, uint amount, address _to, address recipient) private returns (uint) {
        IBlackholeRouter.route[] memory routes = new IBlackholeRouter.route[](1);
        routes[0] = IBlackholeRouter.route({
            pair: GFANG_LP_TOKEN,
            from: _from,
            to: _to,
            stable: false,
            concentrated: false,
            receiver: recipient
        });

        uint256 minAmountOut = _estimateSwap(_from, amount, _to);

        uint[] memory amounts = IBlackholeRouter(BLACKHOLE_ROUTER).swapExactTokensForTokens(
            amount,
            minAmountOut, // Use calculated minimum amount instead of 0
            routes,
            recipient,
            block.timestamp
        );

        require(amounts[amounts.length-1] >= minAmountOut, "amount smaller than estimate");
        return amounts[amounts.length - 1];
    }

    // @_in - Token we want to throw in
    // @amount - amount of our _in
    // @out - address of LP we are going to get

    function estimateZapIn(address _in, uint256 amount) public view returns (uint256, uint256, uint256, uint256) {
        address other = (_in == WETH_TOKEN || _in == address(0)) ? GFANG_TOKEN : WETH_TOKEN;
        (uint256 amountOfTokenIn, uint256 amountToSwapForOtherToken, uint256 amountOtherForLiquidityEstimate) = getTokenAmountsForLiquidity(_in, amount);

        if (_in == IUniswapV2Pair(GFANG_LP_TOKEN).token0()) {
            (uint256 amountIn, uint256 amountOther, uint256 liquidity) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteAddLiquidity(_in, other, false, amountOfTokenIn, amountOtherForLiquidityEstimate);
            return (amountIn, amountOther, amountToSwapForOtherToken, liquidity);
        } else {
            (uint256 amountOther, uint256 amountIn, uint256 liquidity) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteAddLiquidity(other, _in, false, amountOtherForLiquidityEstimate, amountOfTokenIn);
            return (amountOther, amountIn, amountToSwapForOtherToken, liquidity);
        }
    }

    function getTokenAmountsForLiquidity(address _in, uint256 amount) public view returns(uint256, uint256, uint256) {
        uint256 amountOfTokenIn = amount.div(2);
        uint256 amountToSwapForOtherToken = amount.sub(amountOfTokenIn);
        uint256 amountOfOtherTokenForLiquidity = _estimateSwap(_in, amountToSwapForOtherToken, _in == WETH_TOKEN ? GFANG_TOKEN : WETH_TOKEN);

        return (amountOfTokenIn, amountToSwapForOtherToken, amountOfOtherTokenForLiquidity);
    }

     // @ _fromLP - LP we want to throw in
    // @ _to - token we want to get out of our LP
    // @ minAmountToken0, minAmountToken1 - coming from UI (min amount of tokens coming from breaking our LP)
    function estimateZapOut(address _out, uint256 _amount) public view returns (uint256) {
        address token0 = IUniswapV2Pair(GFANG_LP_TOKEN).token0();
        address token1 = IUniswapV2Pair(GFANG_LP_TOKEN).token1();

        (uint256 _amountToken0, uint256 _amountToken1) = IBlackholeRouter(BLACKHOLE_ROUTER).quoteRemoveLiquidity(token0, token1, false, _amount);
        if(token0 == _out) { // if eth, need to swap token1
            return _estimateSwap(token1, _amountToken1, _out).add(_amountToken0);
        } else {
            return _estimateSwap(token0, _amountToken0, _out).add(_amountToken1);
        }
    }
    
    // @_in - token we want to throw in
    // @amount - amount of our _in
    // @out - token we want to get out
    function _estimateSwap(address _in, uint256 amount, address out) public view returns (uint256) {
        IBlackholeRouter.route[] memory routes = new IBlackholeRouter.route[](1);
        routes[0] = IBlackholeRouter.route({
            pair: GFANG_LP_TOKEN,
            from: _in,
            to: out,
            stable: false,
            concentrated: false,
            receiver: address(this)
        });

        uint256[] memory amounts = IBlackholeRouter(BLACKHOLE_ROUTER_HELPER).getAmountsOut(amount, routes);
        return amounts[amounts.length - 1];
    }
    /* ========== Private Functions ========== */

    function _approveTokenIfNeeded(address token, address router) private {
        if (IERC20(token).allowance(address(this), router) == 0) {
            IERC20(token).safeApprove(router, type(uint256).max);
        }
    }

    function retrieveDust(address token, address recipient) private {
        if (token == address(0)) {
            payable(recipient).transfer(address(this).balance);
            return;
        }
        IERC20(token).transfer(recipient, IERC20(token).balanceOf(address(this)));
    }

    /* ========== RESTRICTED FUNCTIONS ========== */
    function withdraw(address token) external onlyOwner {
        if (token == address(0)) {
            payable(owner()).transfer(address(this).balance);
            return;
        }
        IERC20(token).transfer(owner(), IERC20(token).balanceOf(address(this)));
    }

    // add receive function
    receive() external payable {}
}