// File: @openzeppelin/contracts/token/ERC20/IERC20.sol

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @openzeppelin/contracts/math/SafeMath.sol

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts/utils/Address.sol

pragma solidity >=0.6.2 <0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol

pragma solidity >=0.6.0 <0.8.0;




/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// File: contracts/lib/DSMath.sol

/// math.sol -- mixin for inline numerical wizardry

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity >0.4.13;

contract DSMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x, "ds-math-add-overflow");
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x, "ds-math-sub-underflow");
    }
    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x, "ds-math-mul-overflow");
    }

    function min(uint x, uint y) internal pure returns (uint z) {
        return x <= y ? x : y;
    }
    function max(uint x, uint y) internal pure returns (uint z) {
        return x >= y ? x : y;
    }
    function imin(int x, int y) internal pure returns (int z) {
        return x <= y ? x : y;
    }
    function imax(int x, int y) internal pure returns (int z) {
        return x >= y ? x : y;
    }

    uint constant WAD = 10 ** 18;
    uint constant RAY = 10 ** 27;

    //rounds to zero if x*y < WAD / 2
    function wmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), WAD / 2) / WAD;
    }
    //rounds to zero if x*y < WAD / 2
    function rmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), RAY / 2) / RAY;
    }
    //rounds to zero if x*y < WAD / 2
    function wdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, WAD), y / 2) / y;
    }
    //rounds to zero if x*y < RAY / 2
    function rdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, RAY), y / 2) / y;
    }

    // This famous algorithm is called "exponentiation by squaring"
    // and calculates x^n with x as fixed-point and n as regular unsigned.
    //
    // It's O(log n), instead of O(n) for naive repeated multiplication.
    //
    // These facts are why it works:
    //
    //  If n is even, then x^n = (x^2)^(n/2).
    //  If n is odd,  then x^n = x * x^(n-1),
    //   and applying the equation for even x gives
    //    x^n = x * (x^2)^((n-1) / 2).
    //
    //  Also, EVM division is flooring and
    //    floor[(n-1) / 2] = floor[n / 2].
    //
    function rpow(uint x, uint n) internal pure returns (uint z) {
        z = n % 2 != 0 ? x : RAY;

        for (n /= 2; n != 0; n /= 2) {
            x = rmul(x, x);

            if (n % 2 != 0) {
                z = rmul(z, x);
            }
        }
    }
}

// File: @chainlink/contracts/src/v0.6/interfaces/AggregatorV3Interface.sol

pragma solidity >=0.6.0;

interface AggregatorV3Interface {

  function decimals() external view returns (uint8);
  function description() external view returns (string memory);
  function version() external view returns (uint256);

  // getRoundData and latestRoundData should both raise "No data present"
  // if they do not have data to report, instead of returning unset values
  // which could be misinterpreted as actual reported values.
  function getRoundData(uint80 _roundId)
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
  function latestRoundData()
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );

}

// File: contracts/interfaces/HegicInterface.sol

pragma solidity >=0.7.2;



enum HegicOptionType {Invalid, Put, Call}
enum State {Inactive, Active, Exercised, Expired}

struct HegicOption {
    State state;
    address payable holder;
    uint256 strike;
    uint256 amount;
    uint256 lockedAmount;
    uint256 premium;
    uint256 expiration;
    HegicOptionType optionType;
}

interface IHegicOptions {
    event Create(
        uint256 indexed id,
        address indexed account,
        uint256 settlementFee,
        uint256 totalFee
    );

    event Exercise(uint256 indexed id, uint256 profit);
    event Expire(uint256 indexed id, uint256 premium);

    function options(uint256)
        external
        view
        returns (
            State state,
            address payable holder,
            uint256 strike,
            uint256 amount,
            uint256 lockedAmount,
            uint256 premium,
            uint256 expiration,
            HegicOptionType optionType
        );

    function create(
        uint256 period,
        uint256 amount,
        uint256 strike,
        HegicOptionType optionType
    ) external payable returns (uint256 optionID);

    function exercise(uint256 optionID) external;

    function priceProvider() external view returns (address);
}

interface IHegicETHOptions is IHegicOptions {
    function fees(
        uint256 period,
        uint256 amount,
        uint256 strike,
        HegicOptionType optionType
    )
        external
        view
        returns (
            uint256 total,
            uint256 settlementFee,
            uint256 strikeFee,
            uint256 periodFee
        );
}

interface IHegicBTCOptions is IHegicOptions {
    function fees(
        uint256 period,
        uint256 amount,
        uint256 strike,
        HegicOptionType optionType
    )
        external
        view
        returns (
            uint256 total,
            uint256 totalETH,
            uint256 settlementFee,
            uint256 strikeFee,
            uint256 periodFee
        );
}

interface IHegicRewards {
    function hegic() external view returns (IERC20);

    function hegicOptions() external view returns (IHegicOptions);

    function rewardsRate() external view returns (uint256);

    function rewardedOptions(uint256 optionId) external view returns (bool);

    function getReward(uint256 optionId) external;
}

// File: contracts/adapters/IProtocolAdapter.sol

pragma solidity >=0.7.2;
pragma experimental ABIEncoderV2;

library ProtocolAdapterTypes {
    enum OptionType {Invalid, Put, Call}

    // We have 2 types of purchase methods so far - by contract and by 0x.
    // Contract is simple because it involves just specifying the option terms you want to buy.
    // ZeroEx involves an off-chain API call which prepares a ZeroExOrder object to be passed into the tx.
    enum PurchaseMethod {Invalid, Contract, ZeroEx}

    /**
     * @notice Terms of an options contract
     * @param underlying is the underlying asset of the options. E.g. For ETH $800 CALL, ETH is the underlying.
     * @param strikeAsset is the asset used to denote the asset paid out when exercising the option.
     *        E.g. For ETH $800 CALL, USDC is the strikeAsset.
     * @param collateralAsset is the asset used to collateralize a short position for the option.
     * @param expiry is the expiry of the option contract. Users can only exercise after expiry in Europeans.
     * @param strikePrice is the strike price of an optio contract.
     *        E.g. For ETH $800 CALL, 800*10**18 is the USDC.
     * @param optionType is the type of option, can only be OptionType.Call or OptionType.Put
     * @param paymentToken is the token used to purchase the option.
     *        E.g. Buy UNI/USDC CALL with WETH as the paymentToken.
     */
    struct OptionTerms {
        address underlying;
        address strikeAsset;
        address collateralAsset;
        uint256 expiry;
        uint256 strikePrice;
        ProtocolAdapterTypes.OptionType optionType;
        address paymentToken;
    }

    /**
     * @notice 0x order for purchasing otokens
     * @param exchangeAddress [deprecated] is the address we call to conduct a 0x trade.
     * Slither flagged this as a potential vulnerability so we hardcoded it.
     * @param buyTokenAddress is the otoken address
     * @param sellTokenAddress is the token used to purchase USDC. This is USDC most of the time.
     * @param allowanceTarget is the address the adapter needs to provide sellToken allowance to so the swap happens
     * @param protocolFee is the fee paid (in ETH) when conducting the trade
     * @param makerAssetAmount is the buyToken amount
     * @param takerAssetAmount is the sellToken amount
     * @param swapData is the encoded msg.data passed by the 0x api response
     */
    struct ZeroExOrder {
        address exchangeAddress;
        address buyTokenAddress;
        address sellTokenAddress;
        address allowanceTarget;
        uint256 protocolFee;
        uint256 makerAssetAmount;
        uint256 takerAssetAmount;
        bytes swapData;
    }
}

interface IProtocolAdapter {
    /**
     * @notice Emitted when a new option contract is purchased
     */
    event Purchased(
        address indexed caller,
        string indexed protocolName,
        address indexed underlying,
        uint256 amount,
        uint256 optionID
    );

    /**
     * @notice Emitted when an option contract is exercised
     */
    event Exercised(
        address indexed caller,
        address indexed options,
        uint256 indexed optionID,
        uint256 amount,
        uint256 exerciseProfit
    );

    /**
     * @notice Name of the adapter. E.g. "HEGIC", "OPYN_V1". Used as index key for adapter addresses
     */
    function protocolName() external pure returns (string memory);

    /**
     * @notice Boolean flag to indicate whether to use option IDs or not.
     * Fungible protocols normally use tokens to represent option contracts.
     */
    function nonFungible() external pure returns (bool);

    /**
     * @notice Returns the purchase method used to purchase options
     */
    function purchaseMethod()
        external
        pure
        returns (ProtocolAdapterTypes.PurchaseMethod);

    /**
     * @notice Check if an options contract exist based on the passed parameters.
     * @param optionTerms is the terms of the option contract
     */
    function optionsExist(ProtocolAdapterTypes.OptionTerms calldata optionTerms)
        external
        view
        returns (bool);

    /**
     * @notice Get the options contract's address based on the passed parameters
     * @param optionTerms is the terms of the option contract
     */
    function getOptionsAddress(
        ProtocolAdapterTypes.OptionTerms calldata optionTerms
    ) external view returns (address);

    /**
     * @notice Gets the premium to buy `purchaseAmount` of the option contract in ETH terms.
     * @param optionTerms is the terms of the option contract
     * @param purchaseAmount is the number of options purchased
     */
    function premium(
        ProtocolAdapterTypes.OptionTerms calldata optionTerms,
        uint256 purchaseAmount
    ) external view returns (uint256 cost);

    /**
     * @notice Amount of profit made from exercising an option contract (current price - strike price).
     *         0 if exercising out-the-money.
     * @param options is the address of the options contract
     * @param optionID is the ID of the option position in non fungible protocols like Hegic.
     * @param amount is the amount of tokens or options contract to exercise.
     */
    function exerciseProfit(
        address options,
        uint256 optionID,
        uint256 amount
    ) external view returns (uint256 profit);

    function canExercise(
        address options,
        uint256 optionID,
        uint256 amount
    ) external view returns (bool);

    /**
     * @notice Purchases the options contract.
     * @param optionTerms is the terms of the option contract
     * @param amount is the purchase amount in Wad units (10**18)
     */
    function purchase(
        ProtocolAdapterTypes.OptionTerms calldata optionTerms,
        uint256 amount,
        uint256 maxCost
    ) external payable returns (uint256 optionID);

    /**
     * @notice Exercises the options contract.
     * @param options is the address of the options contract
     * @param optionID is the ID of the option position in non fungible protocols like Hegic.
     * @param amount is the amount of tokens or options contract to exercise.
     * @param recipient is the account that receives the exercised profits.
     * This is needed since the adapter holds all the positions
     */
    function exercise(
        address options,
        uint256 optionID,
        uint256 amount,
        address recipient
    ) external payable;

    /**
     * @notice Opens a short position for a given `optionTerms`.
     * @param optionTerms is the terms of the option contract
     * @param amount is the short position amount
     */
    function createShort(
        ProtocolAdapterTypes.OptionTerms calldata optionTerms,
        uint256 amount
    ) external returns (uint256);

    /**
     * @notice Closes an existing short position. In the future,
     * we may want to open this up to specifying a particular short position to close.
     */
    function closeShort() external returns (uint256);
}

// File: contracts/adapters/IAmmAdapter.sol

pragma solidity >=0.7.2;

interface IAmmAdapter {
    function protocolName() external pure returns (string memory);

    function nonFungible() external pure returns (bool);

    function expectedWbtcOut(uint256 ethAmt) external view returns (uint256);

    function expectedDiggOut(uint256 wbtcAmt)
        external
        view
        returns (uint256 diggOut, uint256 tradeAmt);

    function buyLp(
        uint256 amt,
        uint256 tradeAmt,
        uint256 minWbtcAmtOut,
        uint256 minDiggAmtOut
    ) external payable;
}

// File: contracts/adapters/AmmAdapter.sol

pragma solidity >=0.7.2;


/**
 * @notice ProtocolAdapter is used to shadow IProtocolAdapter
 * to provide functions that delegatecall's the underlying IProtocolAdapter functions.
 */
library AmmAdapter {
    function delegateBuyLp(
        IAmmAdapter adapter,
        uint256 amt,
        uint256 tradeAmt,
        uint256 minWbtcAmtOut,
        uint256 minDiggAmtOut
    ) external {
        (bool success, bytes memory result) =
            address(adapter).delegatecall(
                abi.encodeWithSignature(
                    "buyLp(uint256,uint256,uint256,uint256)",
                    amt,
                    tradeAmt,
                    minWbtcAmtOut,
                    minDiggAmtOut
                )
            );
        revertWhenFail(success, result);
    }

    function revertWhenFail(bool success, bytes memory returnData)
        private
        pure
    {
        if (success) return;
        revert(getRevertMsg(returnData));
    }

    function getRevertMsg(bytes memory _returnData)
        private
        pure
        returns (string memory)
    {
        // If the _res length is less than 68, then the transaction failed silently (without a revert message)
        if (_returnData.length < 68) return "ProtocolAdapter: reverted";

        assembly {
            // Slice the sighash.
            _returnData := add(_returnData, 0x04)
        }
        return abi.decode(_returnData, (string)); // All that remains is the revert string
    }
}

// File: contracts/adapters/ProtocolAdapter.sol

pragma solidity >=0.7.2;


/**
 * @notice ProtocolAdapter is used to shadow IProtocolAdapter to provide functions
 * that delegatecall's the underlying IProtocolAdapter functions.
 */
library ProtocolAdapter {
    function delegateOptionsExist(
        IProtocolAdapter adapter,
        ProtocolAdapterTypes.OptionTerms calldata optionTerms
    ) external view returns (bool) {
        (bool success, bytes memory result) =
            address(adapter).staticcall(
                abi.encodeWithSignature(
                    "optionsExist((address,address,address,uint256,uint256,uint8,address))",
                    optionTerms
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (bool));
    }

    function delegateGetOptionsAddress(
        IProtocolAdapter adapter,
        ProtocolAdapterTypes.OptionTerms calldata optionTerms
    ) external view returns (address) {
        (bool success, bytes memory result) =
            address(adapter).staticcall(
                abi.encodeWithSignature(
                    "getOptionsAddress((address,address,address,uint256,uint256,uint8,address))",
                    optionTerms
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (address));
    }

    function delegatePremium(
        IProtocolAdapter adapter,
        ProtocolAdapterTypes.OptionTerms calldata optionTerms,
        uint256 purchaseAmount
    ) external view returns (uint256) {
        (bool success, bytes memory result) =
            address(adapter).staticcall(
                abi.encodeWithSignature(
                    "premium((address,address,address,uint256,uint256,uint8,address),uint256)",
                    optionTerms,
                    purchaseAmount
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (uint256));
    }

    function delegateExerciseProfit(
        IProtocolAdapter adapter,
        address options,
        uint256 optionID,
        uint256 amount
    ) external view returns (uint256) {
        (bool success, bytes memory result) =
            address(adapter).staticcall(
                abi.encodeWithSignature(
                    "exerciseProfit(address,uint256,uint256)",
                    options,
                    optionID,
                    amount
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (uint256));
    }

    function delegatePurchase(
        IProtocolAdapter adapter,
        ProtocolAdapterTypes.OptionTerms calldata optionTerms,
        uint256 purchaseAmount,
        uint256 maxCost
    ) external returns (uint256) {
        (bool success, bytes memory result) =
            address(adapter).delegatecall(
                abi.encodeWithSignature(
                    "purchase((address,address,address,uint256,uint256,uint8,address),uint256,uint256)",
                    optionTerms,
                    purchaseAmount,
                    maxCost
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (uint256));
    }

    function delegatePurchaseWithZeroEx(
        IProtocolAdapter adapter,
        ProtocolAdapterTypes.OptionTerms calldata optionTerms,
        ProtocolAdapterTypes.ZeroExOrder calldata zeroExOrder
    ) external {
        (bool success, bytes memory result) =
            address(adapter).delegatecall(
                abi.encodeWithSignature(
                    // solhint-disable-next-line
                    "purchaseWithZeroEx((address,address,address,uint256,uint256,uint8,address),(address,address,address,address,uint256,uint256,uint256,bytes))",
                    optionTerms,
                    zeroExOrder
                )
            );
        revertWhenFail(success, result);
    }

    function delegateExercise(
        IProtocolAdapter adapter,
        address options,
        uint256 optionID,
        uint256 amount,
        address recipient
    ) external {
        (bool success, bytes memory result) =
            address(adapter).delegatecall(
                abi.encodeWithSignature(
                    "exercise(address,uint256,uint256,address)",
                    options,
                    optionID,
                    amount,
                    recipient
                )
            );
        revertWhenFail(success, result);
    }

    function delegateClaimRewards(
        IProtocolAdapter adapter,
        address rewardsAddress,
        uint256[] calldata optionIDs
    ) external returns (uint256) {
        (bool success, bytes memory result) =
            address(adapter).delegatecall(
                abi.encodeWithSignature(
                    "claimRewards(address,uint256[])",
                    rewardsAddress,
                    optionIDs
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (uint256));
    }

    function delegateRewardsClaimable(
        IProtocolAdapter adapter,
        address rewardsAddress,
        uint256[] calldata optionIDs
    ) external view returns (uint256) {
        (bool success, bytes memory result) =
            address(adapter).staticcall(
                abi.encodeWithSignature(
                    "rewardsClaimable(address,uint256[])",
                    rewardsAddress,
                    optionIDs
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (uint256));
    }

    function delegateCreateShort(
        IProtocolAdapter adapter,
        ProtocolAdapterTypes.OptionTerms calldata optionTerms,
        uint256 amount
    ) external returns (uint256) {
        (bool success, bytes memory result) =
            address(adapter).delegatecall(
                abi.encodeWithSignature(
                    "createShort((address,address,address,uint256,uint256,uint8,address),uint256)",
                    optionTerms,
                    amount
                )
            );
        revertWhenFail(success, result);
        return abi.decode(result, (uint256));
    }

    function delegateCloseShort(IProtocolAdapter adapter)
        external
        returns (uint256)
    {
        (bool success, bytes memory result) =
            address(adapter).delegatecall(
                abi.encodeWithSignature("closeShort()")
            );
        revertWhenFail(success, result);
        return abi.decode(result, (uint256));
    }

    function revertWhenFail(bool success, bytes memory returnData)
        private
        pure
    {
        if (success) return;
        revert(getRevertMsg(returnData));
    }

    function getRevertMsg(bytes memory _returnData)
        private
        pure
        returns (string memory)
    {
        // If the _res length is less than 68, then the transaction failed silently (without a revert message)
        if (_returnData.length < 68) return "ProtocolAdapter: reverted";

        assembly {
            // Slice the sighash.
            _returnData := add(_returnData, 0x04)
        }
        return abi.decode(_returnData, (string)); // All that remains is the revert string
    }
}

// File: contracts/interfaces/IRibbonFactory.sol

pragma solidity >=0.7.2;

interface IRibbonFactory {
    function isInstrument(address instrument) external returns (bool);

    function getAdapter(string calldata protocolName)
        external
        view
        returns (address);

    function getAdapters()
        external
        view
        returns (address[] memory adaptersArray);

    function burnGasTokens() external;
}

// File: contracts/interfaces/IUniswapV2Pair.sol

pragma solidity >=0.6.0;

interface IUniswapV2Pair {
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 value);

    function getReserves()
        external
        view
        returns (
            uint112 reserve0,
            uint112 reserve1,
            uint32 blockTimestampLast
        );

    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);
}

// File: contracts/interfaces/IUniswapV2Router.sol

pragma solidity >=0.7.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    )
        external
        returns (
            uint256 amountA,
            uint256 amountB,
            uint256 liquidity
        );

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );

    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB);

    function removeLiquidityETH(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountToken, uint256 amountETH);

    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountA, uint256 amountB);

    function removeLiquidityETHWithPermit(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountToken, uint256 amountETH);

    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapTokensForExactTokens(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactETHForTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function swapTokensForExactETH(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactTokensForETH(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapETHForExactTokens(
        uint256 amountOut,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function quote(
        uint256 amountA,
        uint256 reserveA,
        uint256 reserveB
    ) external pure returns (uint256 amountB);

    function getAmountOut(
        uint256 amountIn,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountOut);

    function getAmountIn(
        uint256 amountOut,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountIn);

    function getAmountsOut(uint256 amountIn, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);

    function getAmountsIn(uint256 amountOut, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);
}

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountETH);

    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;
}

// File: contracts/adapters/UniswapAdapter.sol

pragma solidity >=0.7.2;

contract UniswapAdapter {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    address public constant ethAddress = address(0);
    address public immutable wethAddress;
    address public immutable wbtcAddress;
    address public immutable diggAddress;
    string private constant _name = "UNISWAP";
    bool private constant _nonFungible = true;
    IUniswapV2Router02 public immutable sushiswapRouter;
    IUniswapV2Pair public immutable wbtcDiggSushiswap;
    IERC20 public immutable wbtcToken;
    IERC20 public immutable diggToken;
    uint256 private constant deadlineBuffer = 150;

    constructor(
        address _sushiswapRouter,
        address _wbtcAddress,
        address _wethAddress,
        address _wbtcDiggSushiswap,
        address _diggAddress
    ) {
        require(_sushiswapRouter != address(0), "!_sushiswapRouter");
        require(_wethAddress != address(0), "!_weth");
        require(_wbtcAddress != address(0), "!_wbtc");
        require(_wbtcDiggSushiswap != address(0), "!_wbtcDiggSushiswap");
        require(_diggAddress != address(0), "!_diggAddress");

        wbtcAddress = _wbtcAddress;
        wethAddress = _wethAddress;
        diggAddress = _diggAddress;
        sushiswapRouter = IUniswapV2Router02(_sushiswapRouter);
        wbtcDiggSushiswap = IUniswapV2Pair(_wbtcDiggSushiswap);
        wbtcToken = IERC20(_wbtcAddress);
        diggToken = IERC20(_diggAddress);
    }

    receive() external payable {}

    function protocolName() public pure returns (string memory) {
        return _name;
    }

    function nonFungible() external pure returns (bool) {
        return _nonFungible;
    }

    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;
        }
    }

    // Code from Alpha Homora
    // The core math involved in getting optimal swap amt to provide amm liquidity
    function getSwapAmt(uint256 amtA, uint256 resA)
        internal
        pure
        returns (uint256)
    {
        return
            sqrt(amtA.mul(resA.mul(3988000) + amtA.mul(3988009))).sub(
                amtA.mul(1997)
            ) / 1994;
    }

    function expectedWbtcOut(uint256 ethAmt) public view returns (uint256) {
        address[] memory path = new address[](2);
        path[0] = wethAddress;
        path[1] = wbtcAddress;
        uint256 wbtcOut = sushiswapRouter.getAmountsOut(ethAmt, path)[1];
        return wbtcOut;
    }

    //this function returns both the expected digg amount out as well as the input trade amt of wbtc used
    //these are both needed as inputs to buyLp
    function expectedDiggOut(uint256 wbtcAmt)
        public
        view
        returns (uint256 diggOut, uint256 tradeAmt)
    {
        (uint112 reserveAmt, , ) =
            IUniswapV2Pair(wbtcDiggSushiswap).getReserves();
        tradeAmt = getSwapAmt(reserveAmt, wbtcAmt);
        address[] memory path = new address[](2);
        path[0] = wbtcAddress;
        path[1] = diggAddress;
        diggOut = sushiswapRouter.getAmountsOut(tradeAmt, path)[1];
    }

    function convertEthToToken(
        uint256 inputAmount,
        address addr,
        uint256 amountOutMin
    ) internal returns (uint256) {
        uint256 amtOut =
            _convertEthToToken(
                inputAmount,
                addr,
                amountOutMin,
                sushiswapRouter
            );
        return amtOut;
    }

    function convertTokenToToken(
        address addr1,
        address addr2,
        uint256 amount,
        uint256 amountOutMin
    ) internal returns (uint256) {
        uint256 amtOut =
            _convertTokenToToken(
                addr1,
                addr2,
                amount,
                amountOutMin,
                sushiswapRouter
            );
        return amtOut;
    }

    function addLiquidity(
        address token1,
        address token2,
        uint256 amount1,
        uint256 amount2
    ) internal returns (uint256) {
        uint256 lpAmt =
            _addLiquidity(token1, token2, amount1, amount2, sushiswapRouter);
        return lpAmt;
    }

    function _convertEthToToken(
        uint256 inputAmount,
        address addr,
        uint256 amountOutMin,
        IUniswapV2Router02 router
    ) internal returns (uint256) {
        uint256 deadline = block.timestamp + deadlineBuffer;
        address[] memory path = new address[](2);
        path[0] = wethAddress;
        path[1] = addr;
        uint256 amtOut =
            router.swapExactETHForTokens{value: inputAmount}(
                amountOutMin,
                path,
                address(this),
                deadline
            )[1];
        return amtOut;
    }

    function _convertTokenToToken(
        address addr1,
        address addr2,
        uint256 amount,
        uint256 amountOutMin,
        IUniswapV2Router02 router
    ) internal returns (uint256) {
        uint256 deadline = block.timestamp + deadlineBuffer;
        address[] memory path = new address[](2);
        path[0] = addr1;
        path[1] = addr2;
        if (wbtcToken.allowance(address(this), address(router)) == 0) {
            wbtcToken.safeApprove(address(router), type(uint256).max);
        }
        uint256 amtOut =
            router.swapExactTokensForTokens(
                amount,
                amountOutMin,
                path,
                address(this),
                deadline
            )[1];
        return amtOut;
    }

    function _addLiquidity(
        address token1,
        address token2,
        uint256 amount1,
        uint256 amount2,
        IUniswapV2Router02 router
    ) internal returns (uint256) {
        uint256 deadline = block.timestamp + deadlineBuffer;
        if (wbtcToken.allowance(address(this), address(router)) < amount1) {
            wbtcToken.safeApprove(address(router), type(uint256).max);
        }
        if (diggToken.allowance(address(this), address(router)) < amount2) {
            diggToken.safeApprove(address(router), type(uint256).max);
        }
        (, , uint256 lpAmt) =
            router.addLiquidity(
                token1,
                token2,
                amount1,
                amount2,
                0,
                0,
                address(this),
                deadline
            );
        return lpAmt;
    }

    //By the time this function is called the user bal should be in wbtc
    //calculates optimal swap amt for minimal leftover funds and buys Digg
    // Provides liquidity and transfers lp token to msg.sender
    function _buyLp(
        uint256 userWbtcBal,
        address traderAccount,
        uint256 tradeAmt,
        uint256 minDiggAmtOut
    ) internal {
        uint256 diggAmt =
            convertTokenToToken(
                wbtcAddress,
                diggAddress,
                tradeAmt,
                minDiggAmtOut
            );
        uint256 lpAmt =
            addLiquidity(wbtcAddress, diggAddress, userWbtcBal, diggAmt);
        require(
            wbtcDiggSushiswap.transfer(traderAccount, lpAmt),
            "transfer failed"
        );
    }

    // token input should be either wbtc or eth
    // valid exchange venues are sushiswap and uniswap
    // the minWbtcAmtOut param isnt used when users pass in wbtc directly
    // use the  expectedWbtcAmtOut and expectedDiggAmtOut functions
    // off chain to calculate trade_amt, minWbtcAmtOut and minDiggAmtOut
    function buyLp(
        uint256 amt,
        uint256 tradeAmt,
        uint256 minWbtcAmtOut,
        uint256 minDiggAmtOut
    ) public payable {
        require(msg.value >= amt, "not enough funds");
        uint256 wbtcAmt = convertEthToToken(amt, wbtcAddress, minWbtcAmtOut);
        _buyLp(wbtcAmt, msg.sender, tradeAmt, minDiggAmtOut);
    }
}

// File: @openzeppelin/contracts/utils/ReentrancyGuard.sol


pragma solidity >=0.6.0 <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 () internal {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

// File: @openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol


pragma solidity >=0.6.2 <0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library AddressUpgradeable {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @openzeppelin/contracts-upgradeable/proxy/Initializable.sol


// solhint-disable-next-line compiler-version
pragma solidity >=0.4.24 <0.8.0;


/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {UpgradeableProxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 */
abstract contract Initializable {

    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        require(_initializing || _isConstructor() || !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }

    /// @dev Returns true if and only if the function is running in the constructor
    function _isConstructor() private view returns (bool) {
        return !AddressUpgradeable.isContract(address(this));
    }
}

// File: @openzeppelin/contracts-upgradeable/utils/ContextUpgradeable.sol

pragma solidity >=0.6.0 <0.8.0;


/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract ContextUpgradeable is Initializable {
    function __Context_init() internal initializer {
        __Context_init_unchained();
    }

    function __Context_init_unchained() internal initializer {
    }
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
    uint256[50] private __gap;
}

// File: @openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol

pragma solidity >=0.6.0 <0.8.0;


/**
 * @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 OwnableUpgradeable is Initializable, ContextUpgradeable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    function __Ownable_init() internal initializer {
        __Context_init_unchained();
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal initializer {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = 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");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
    uint256[49] private __gap;
}

// File: @openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20Upgradeable {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @openzeppelin/contracts-upgradeable/math/SafeMathUpgradeable.sol

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMathUpgradeable {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts-upgradeable/token/ERC20/ERC20Upgradeable.sol

pragma solidity >=0.6.0 <0.8.0;





/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20Upgradeable is Initializable, ContextUpgradeable, IERC20Upgradeable {
    using SafeMathUpgradeable for uint256;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    function __ERC20_init(string memory name_, string memory symbol_) internal initializer {
        __Context_init_unchained();
        __ERC20_init_unchained(name_, symbol_);
    }

    function __ERC20_init_unchained(string memory name_, string memory symbol_) internal initializer {
        _name = name_;
        _symbol = symbol_;
        _decimals = 18;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual returns (uint8) {
        return _decimals;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal virtual {
        _decimals = decimals_;
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
    uint256[44] private __gap;
}

// File: contracts/storage/StakedPutStorage.sol
pragma solidity >=0.7.2;

contract StakedPutStorageV1 is
    OwnableUpgradeable,
    ERC20Upgradeable,
    ReentrancyGuard
{
    struct InstrumentPosition {
        bool exercised;
        uint8 putVenueID;
        uint32 putOptionID;
        uint256 amount;
    }

    mapping(address => InstrumentPosition[]) instrumentPositions;

    function numOfPositions(address _account) public view returns (uint256) {
        return instrumentPositions[_account].length;
    }

    function getInstrumentPositions(address account)
        external
        view
        returns (InstrumentPosition[] memory positions)
    {
        return instrumentPositions[account];
    }

    function instrumentPosition(address account, uint256 positionID)
        external
        view
        returns (InstrumentPosition memory position)
    {
        return instrumentPositions[account][positionID];
    }
}

// File: contracts/experimental/StakedPut.sol

pragma solidity >=0.7.2;


contract StakedPut is DSMath, StakedPutStorageV1 {
    event PositionCreated(
        address indexed account,
        uint256 indexed positionID,
        uint256 amount
    );
    event Exercised(
        address indexed account,
        uint256 indexed positionID,
        uint256 totalProfit
    );

    struct BuyInstrumentParams {
        uint256 putStrikePrice;
        uint256 optionAmount;
        uint256 putMaxCost;
        uint256 expiry;
        uint256 lpAmt;
        uint256 tradeAmt;
        uint256 minWbtcAmtOut;
        uint256 minDiggAmtOut;
    }

    using AmmAdapter for IAmmAdapter;
    using ProtocolAdapter for IProtocolAdapter;
    using SafeERC20 for IERC20;
    using SafeMath for uint256;

    IRibbonFactory public immutable factory;
    IProtocolAdapter public immutable adapter;
    IAmmAdapter public immutable iUniswapAdapter;
    AggregatorV3Interface public immutable priceProvider;

    address payable public uniswapAdapterAddress;
    string private constant instrumentName = "wbtc/digg-staked-put";
    uint256 private constant timePeriod = 2419199;
    string private constant venue = "HEGIC";
    uint8 private constant venueID = 0;

    ProtocolAdapterTypes.OptionType public constant optionType =
        ProtocolAdapterTypes.OptionType.Put;
    address public constant ethAddress = address(0);
    address public immutable wbtcAddress;
    address public immutable underlying;
    address public immutable strikeAsset;
    address public immutable collateralAsset;
    address public immutable optionsAddress;
    address public immutable adapterAddress;

    constructor(
        address _factory,
        address payable _uniswapAdapterAddress,
        address _wbtcAddress,
        address _wbtcOptionsAddress,
        address _collateralAsset,
        address _priceFeed
    ) {
        require(_factory != address(0), "!_factory");
        require(_uniswapAdapterAddress != address(0), "!_uniswapAdapter");
        require(_wbtcAddress != address(0), "!_wbtc");
        require(_wbtcOptionsAddress != address(0), "!_wbtcOptions");
        require(_collateralAsset != address(0), "!_collateral");
        require(_priceFeed != address(0), "!_priceFeed");

        wbtcAddress = _wbtcAddress;
        underlying = _wbtcAddress;
        strikeAsset = _wbtcAddress;
        collateralAsset = _collateralAsset;
        priceProvider = AggregatorV3Interface(_priceFeed);
        IRibbonFactory factoryInstance = IRibbonFactory(_factory);
        iUniswapAdapter = IAmmAdapter(_uniswapAdapterAddress);
        uniswapAdapterAddress = _uniswapAdapterAddress;
        address _adapterAddress = factoryInstance.getAdapter(venue);
        require(_adapterAddress != address(0), "Adapter not set");
        adapterAddress = _adapterAddress;
        factory = factoryInstance;
        adapter = IProtocolAdapter(_adapterAddress);
        optionsAddress = _wbtcOptionsAddress;
    }

    function initialize() external initializer {}

    receive() external payable {}

    function getName() public pure returns (string memory) {
        return instrumentName;
    }

    function getCurrentPrice() public view returns (uint256) {
        (, int256 latestPrice, , , ) = priceProvider.latestRoundData();
        uint256 currentPrice = uint256(latestPrice);
        return currentPrice.mul(10**10);
    }

    //input currency is eth
    function getInputs(uint256 amt)
        public
        view
        returns (
            uint256 wbtcSize,
            uint256 expDigg,
            uint256 tradeAmt,
            uint256 premium,
            uint256 totalCost,
            uint256 currentPrice,
            uint256 expiry
        )
    {
        wbtcSize = iUniswapAdapter.expectedWbtcOut(amt);

        (expDigg, tradeAmt) = iUniswapAdapter.expectedDiggOut(wbtcSize);

        //set expiry to a month from now
        //set strike to atm
        expiry = block.timestamp + timePeriod;
        currentPrice = uint256(getCurrentPrice());

        ProtocolAdapterTypes.OptionTerms memory optionTerms =
            ProtocolAdapterTypes.OptionTerms(
                underlying,
                strikeAsset,
                collateralAsset,
                expiry,
                currentPrice,
                optionType,
                ethAddress
            );

        premium = adapter.premium(optionTerms, wbtcSize);
        totalCost = amt.add(premium);
    }

    function buyInstrument(BuyInstrumentParams calldata params) public payable {
        require(msg.value > 0, "input must be eth");
        iUniswapAdapter.delegateBuyLp(
            params.lpAmt,
            params.tradeAmt,
            params.minWbtcAmtOut,
            params.minDiggAmtOut
        );
        uint256 positionID = buyPutFromAdapter(params);

        uint256 balance = address(this).balance;
        if (balance > 0) payable(msg.sender).transfer(balance);

        emit PositionCreated(msg.sender, positionID, params.lpAmt);
    }

    function exercisePosition(uint256 positionID)
        external
        nonReentrant
        returns (uint256 totalProfit)
    {
        InstrumentPosition storage position =
            instrumentPositions[msg.sender][positionID];
        require(!position.exercised, "Already exercised");

        uint32 optionID;

        optionID = position.putOptionID;

        uint256 amount = position.amount;

        uint256 profit =
            adapter.delegateExerciseProfit(optionsAddress, optionID, amount);
        if (profit > 0) {
            adapter.delegateExercise(
                optionsAddress,
                optionID,
                amount,
                msg.sender
            );
        }

        totalProfit += profit;

        position.exercised = true;

        emit Exercised(msg.sender, positionID, totalProfit);
    }

    function exerciseProfit(address account, uint256 positionID)
        external
        view
        returns (uint256)
    {
        InstrumentPosition storage position =
            instrumentPositions[account][positionID];

        if (position.exercised) return 0;

        uint256 profit = 0;

        uint256 amount = position.amount;

        uint32 optionID;

        optionID = position.putOptionID;

        profit += adapter.delegateExerciseProfit(
            optionsAddress,
            optionID,
            amount
        );
        return profit;
    }

    function canExercise(address account, uint256 positionID)
        external
        view
        returns (bool)
    {
        InstrumentPosition storage position =
            instrumentPositions[account][positionID];

        if (position.exercised) return false;

        bool canExercisePut = false;

        uint32 optionID;

        optionID = position.putOptionID;

        bool canExerciseOptions =
            adapter.canExercise(optionsAddress, optionID, position.amount);

        if (canExerciseOptions) {
            canExercisePut = true;
        }
        return canExercisePut;
    }

    //make this internal for production
    function buyPutFromAdapter(BuyInstrumentParams calldata params)
        public
        payable
        nonReentrant
        returns (uint256 positionID)
    {
        require(
            block.timestamp < params.expiry,
            "Cannot purchase after expiry"
        );

        ProtocolAdapterTypes.OptionTerms memory optionTerms =
            ProtocolAdapterTypes.OptionTerms(
                underlying,
                strikeAsset,
                collateralAsset,
                params.expiry,
                params.putStrikePrice,
                optionType,
                ethAddress
            );

        uint256 optionID256 =
            adapter.delegatePurchase(
                optionTerms,
                params.optionAmount,
                params.putMaxCost
            );
        uint32 optionID = uint32(optionID256);

        InstrumentPosition memory position =
            InstrumentPosition(false, venueID, optionID, params.optionAmount);

        positionID = instrumentPositions[msg.sender].length;
        instrumentPositions[msg.sender].push(position);
    }
}