// SPDX-License-Identifier: MIT

pragma solidity 0.7.5;



// Part: OpenZeppelin/[email protected]/Address

/**
 * @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);
            }
        }
    }
}

// Part: Proxy

/**
 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
 * be specified by overriding the virtual {_implementation} function.
 *
 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
 * different contract through the {_delegate} function.
 *
 * The success and return data of the delegated call will be returned back to the caller of the proxy.
 */
abstract contract Proxy {
    /**
     * @dev Delegates the current call to `implementation`.
     *
     * This function does not return to its internal call site, it will return directly to the external caller.
     */
    function _delegate(address implementation) internal virtual {
        assembly {
            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())

            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)

            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())

            switch result
            // delegatecall returns 0 on error.
            case 0 {
                revert(0, returndatasize())
            }
            default {
                return(0, returndatasize())
            }
        }
    }

    /**
     * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal view virtual returns (address);

    /**
     * @dev Delegates the current call to the address returned by `_implementation()`.
     *
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _fallback() internal virtual {
        _beforeFallback();
        _delegate(_implementation());
    }

    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
     * function in the contract matches the call data.
     */
    fallback() external payable virtual {
        _fallback();
    }

    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
     * is empty.
     */
    receive() external payable virtual {
        _fallback();
    }

    /**
     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
     * call, or as part of the Solidity `fallback` or `receive` functions.
     *
     * If overriden should call `super._beforeFallback()`.
     */
    function _beforeFallback() internal virtual {}
}

// Part: StorageSlot

/**
 * @dev Library for reading and writing primitive types to specific storage slots.
 *
 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
 * This library helps with reading and writing to such slots without the need for inline assembly.
 *
 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
 *
 * Example usage to set ERC1967 implementation slot:
 * ```
 * contract ERC1967 {
 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
 *
 *     function _getImplementation() internal view returns (address) {
 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
 *     }
 *
 *     function _setImplementation(address newImplementation) internal {
 *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
 *     }
 * }
 * ```
 *
 * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }

    struct BooleanSlot {
        bool value;
    }

    struct Bytes32Slot {
        bytes32 value;
    }

    struct Uint256Slot {
        uint256 value;
    }

    /**
     * @dev Returns an `AddressSlot` with member `value` located at `slot`.
     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        assembly {
            r.slot := slot
        }
    }
}

// Part: ERC1967Upgrade

/**
 * @dev This abstract contract provides getters and event emitting update functions for
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
 *
 * _Available since v4.1._
 *
 */
abstract contract ERC1967Upgrade {
    // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
    bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;

    /**
     * @dev Storage slot with the address of the current implementation.
     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;

    /**
     * @dev Emitted when the implementation is upgraded.
     */
    event Upgraded(address indexed implementation);

    /**
     * @dev Returns the current implementation address.
     */
    function _getImplementation() internal view returns (address) {
        return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
    }

    /**
     * @dev Stores a new address in the EIP1967 implementation slot.
     */
    function _setImplementation(address newImplementation) private {
        require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
        StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
    }

    /**
     * @dev Perform implementation upgrade
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeTo(address newImplementation) internal {
        _setImplementation(newImplementation);
        emit Upgraded(newImplementation);
    }

    /**
     * @dev Perform implementation upgrade with additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCall(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        _upgradeTo(newImplementation);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(newImplementation, data);
        }
    }

    /**
     * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCallSecure(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        address oldImplementation = _getImplementation();

        // Initial upgrade and setup call
        _setImplementation(newImplementation);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(newImplementation, data);
        }

        // Perform rollback test if not already in progress
        StorageSlot.BooleanSlot storage rollbackTesting = StorageSlot.getBooleanSlot(_ROLLBACK_SLOT);
        if (!rollbackTesting.value) {
            // Trigger rollback using upgradeTo from the new implementation
            rollbackTesting.value = true;
            Address.functionDelegateCall(
                newImplementation,
                abi.encodeWithSignature("upgradeTo(address)", oldImplementation)
            );
            rollbackTesting.value = false;
            // Check rollback was effective
            require(oldImplementation == _getImplementation(), "ERC1967Upgrade: upgrade breaks further upgrades");
            // Finally reset to the new implementation and log the upgrade
            _upgradeTo(newImplementation);
        }
    }

}

// Part: ERC1967Proxy

/**
 * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
 * implementation address that can be changed. This address is stored in storage in the location specified by
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
 * implementation behind the proxy.
 */
contract ERC1967Proxy is Proxy, ERC1967Upgrade {
    /**
     * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
     *
     * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
     * function call, and allows initializating the storage of the proxy like a Solidity constructor.
     */
    constructor(address _logic, bytes memory _data) payable {
        assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
        _upgradeToAndCall(_logic, _data, false);
    }

    /**
     * @dev Returns the current implementation address.
     */
    function _implementation() internal view virtual override returns (address impl) {
        return ERC1967Upgrade._getImplementation();
    }
}

// File: nProxy.sol

contract nProxy is ERC1967Proxy {
    constructor(
        address _logic,
        bytes memory _data
    ) ERC1967Proxy(_logic, _data) {}

    receive() external payable override {
        // Allow ETH transfers to succeed
    }

    function getImplementation() external view returns (address) {
        return _getImplementation();
    }
}

// File: contracts/interfaces/IUniswapV2Pair.sol

pragma solidity >=0.5.0;

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

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

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

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

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}

// File: contracts/interfaces/IUniswapV2ERC20.sol

pragma solidity >=0.5.0;

interface IUniswapV2ERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

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

// File: contracts/libraries/SafeMath.sol

pragma solidity =0.5.16;

// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)

library SafeMath {
    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');
    }
}

// File: contracts/UniswapV2ERC20.sol

pragma solidity =0.5.16;



contract UniswapV2ERC20 is IUniswapV2ERC20 {
    using SafeMath for uint;

    string public constant name = 'Uniswap V2';
    string public constant symbol = 'UNI-V2';
    uint8 public constant decimals = 18;
    uint  public totalSupply;
    mapping(address => uint) public balanceOf;
    mapping(address => mapping(address => uint)) public allowance;

    bytes32 public DOMAIN_SEPARATOR;
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint) public nonces;

    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    constructor() public {
        uint chainId;
        assembly {
            chainId := chainid
        }
        DOMAIN_SEPARATOR = keccak256(
            abi.encode(
                keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
                keccak256(bytes(name)),
                keccak256(bytes('1')),
                chainId,
                address(this)
            )
        );
    }

    function _mint(address to, uint value) internal {
        totalSupply = totalSupply.add(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(address(0), to, value);
    }

    function _burn(address from, uint value) internal {
        balanceOf[from] = balanceOf[from].sub(value);
        totalSupply = totalSupply.sub(value);
        emit Transfer(from, address(0), value);
    }

    function _approve(address owner, address spender, uint value) private {
        allowance[owner][spender] = value;
        emit Approval(owner, spender, value);
    }

    function _transfer(address from, address to, uint value) private {
        balanceOf[from] = balanceOf[from].sub(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(from, to, value);
    }

    function approve(address spender, uint value) external returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }

    function transfer(address to, uint value) external returns (bool) {
        _transfer(msg.sender, to, value);
        return true;
    }

    function transferFrom(address from, address to, uint value) external returns (bool) {
        if (allowance[from][msg.sender] != uint(-1)) {
            allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
        }
        _transfer(from, to, value);
        return true;
    }

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
        require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
        bytes32 digest = keccak256(
            abi.encodePacked(
                '\x19\x01',
                DOMAIN_SEPARATOR,
                keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
            )
        );
        address recoveredAddress = ecrecover(digest, v, r, s);
        require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
        _approve(owner, spender, value);
    }
}

// File: contracts/libraries/Math.sol

pragma solidity =0.5.16;

// a library for performing various math operations

library Math {
    function min(uint x, uint y) internal pure returns (uint z) {
        z = x < y ? x : y;
    }

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

// File: contracts/libraries/UQ112x112.sol

pragma solidity =0.5.16;

// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))

// range: [0, 2**112 - 1]
// resolution: 1 / 2**112

library UQ112x112 {
    uint224 constant Q112 = 2**112;

    // encode a uint112 as a UQ112x112
    function encode(uint112 y) internal pure returns (uint224 z) {
        z = uint224(y) * Q112; // never overflows
    }

    // divide a UQ112x112 by a uint112, returning a UQ112x112
    function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
        z = x / uint224(y);
    }
}

// File: contracts/interfaces/IERC20.sol

pragma solidity >=0.5.0;

interface IERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);
}

// File: contracts/interfaces/IUniswapV2Factory.sol

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// File: contracts/interfaces/IUniswapV2Callee.sol

pragma solidity >=0.5.0;

interface IUniswapV2Callee {
    function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
}

// File: contracts/UniswapV2Pair.sol

pragma solidity =0.5.16;








contract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {
    using SafeMath  for uint;
    using UQ112x112 for uint224;

    uint public constant MINIMUM_LIQUIDITY = 10**3;
    bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));

    address public factory;
    address public token0;
    address public token1;

    uint112 private reserve0;           // uses single storage slot, accessible via getReserves
    uint112 private reserve1;           // uses single storage slot, accessible via getReserves
    uint32  private blockTimestampLast; // uses single storage slot, accessible via getReserves

    uint public price0CumulativeLast;
    uint public price1CumulativeLast;
    uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event

    uint private unlocked = 1;
    modifier lock() {
        require(unlocked == 1, 'UniswapV2: LOCKED');
        unlocked = 0;
        _;
        unlocked = 1;
    }

    function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
        _reserve0 = reserve0;
        _reserve1 = reserve1;
        _blockTimestampLast = blockTimestampLast;
    }

    function _safeTransfer(address token, address to, uint value) private {
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
    }

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

    constructor() public {
        factory = msg.sender;
    }

    // called once by the factory at time of deployment
    function initialize(address _token0, address _token1) external {
        require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
        token0 = _token0;
        token1 = _token1;
    }

    // update reserves and, on the first call per block, price accumulators
    function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
        require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
        uint32 blockTimestamp = uint32(block.timestamp % 2**32);
        uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
        if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
            // * never overflows, and + overflow is desired
            price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
            price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
        }
        reserve0 = uint112(balance0);
        reserve1 = uint112(balance1);
        blockTimestampLast = blockTimestamp;
        emit Sync(reserve0, reserve1);
    }

    // if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)
    function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
        address feeTo = IUniswapV2Factory(factory).feeTo();
        feeOn = feeTo != address(0);
        uint _kLast = kLast; // gas savings
        if (feeOn) {
            if (_kLast != 0) {
                uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
                uint rootKLast = Math.sqrt(_kLast);
                if (rootK > rootKLast) {
                    uint numerator = totalSupply.mul(rootK.sub(rootKLast));
                    uint denominator = rootK.mul(5).add(rootKLast);
                    uint liquidity = numerator / denominator;
                    if (liquidity > 0) _mint(feeTo, liquidity);
                }
            }
        } else if (_kLast != 0) {
            kLast = 0;
        }
    }

    // this low-level function should be called from a contract which performs important safety checks
    function mint(address to) external lock returns (uint liquidity) {
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        uint balance0 = IERC20(token0).balanceOf(address(this));
        uint balance1 = IERC20(token1).balanceOf(address(this));
        uint amount0 = balance0.sub(_reserve0);
        uint amount1 = balance1.sub(_reserve1);

        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
        if (_totalSupply == 0) {
            liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
           _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
        } else {
            liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
        }
        require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
        _mint(to, liquidity);

        _update(balance0, balance1, _reserve0, _reserve1);
        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
        emit Mint(msg.sender, amount0, amount1);
    }

    // this low-level function should be called from a contract which performs important safety checks
    function burn(address to) external lock returns (uint amount0, uint amount1) {
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        address _token0 = token0;                                // gas savings
        address _token1 = token1;                                // gas savings
        uint balance0 = IERC20(_token0).balanceOf(address(this));
        uint balance1 = IERC20(_token1).balanceOf(address(this));
        uint liquidity = balanceOf[address(this)];

        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
        amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
        amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
        require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
        _burn(address(this), liquidity);
        _safeTransfer(_token0, to, amount0);
        _safeTransfer(_token1, to, amount1);
        balance0 = IERC20(_token0).balanceOf(address(this));
        balance1 = IERC20(_token1).balanceOf(address(this));

        _update(balance0, balance1, _reserve0, _reserve1);
        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
        emit Burn(msg.sender, amount0, amount1, to);
    }

    // this low-level function should be called from a contract which performs important safety checks
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
        require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');

        uint balance0;
        uint balance1;
        { // scope for _token{0,1}, avoids stack too deep errors
        address _token0 = token0;
        address _token1 = token1;
        require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
        if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
        if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
        if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
        balance0 = IERC20(_token0).balanceOf(address(this));
        balance1 = IERC20(_token1).balanceOf(address(this));
        }
        uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
        uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
        require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
        { // scope for reserve{0,1}Adjusted, avoids stack too deep errors
        uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
        uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
        require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
        }

        _update(balance0, balance1, _reserve0, _reserve1);
        emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
    }

    // force balances to match reserves
    function skim(address to) external lock {
        address _token0 = token0; // gas savings
        address _token1 = token1; // gas savings
        _safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));
        _safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));
    }

    // force reserves to match balances
    function sync() external lock {
        _update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);
    }
}

// Copyright (C) 2015, 2016, 2017 Dapphub

// 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 ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

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*/

// SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.7.0;
pragma abicoder v2;
import "interfaces/notional/NotionalProxy.sol";
import "@openzeppelin/contracts/proxy/Initializable.sol";
import "@openzeppelin/contracts/cryptography/ECDSA.sol";
import "../../proxy/utils/UUPSUpgradeable.sol";
/// @title Note ERC20 Token
/// Fork of Compound Comp token at commit hash
/// https://github.com/compound-finance/compound-protocol/commit/9bcff34a5c9c76d51e51bcb0ca1139588362ef96
contract NoteERC20 is Initializable, UUPSUpgradeable {
    /// @notice EIP-20 token name for this token
    string public constant name = "Notional";
    /// @notice EIP-20 token symbol for this token
    string public constant symbol = "NOTE";
    /// @notice EIP-20 token decimals for this token
    uint8 public constant decimals = 8;
    /// @notice Total number of tokens in circulation (100 million NOTE)
    uint256 public constant totalSupply = 100000000e8;
    /// @notice Notional router address, not currently used but cannot be
    /// removed or this will mess up storage.
    NotionalProxy public notionalProxy;
    // Allowance amounts on behalf of others
    mapping(address => mapping(address => uint96)) internal allowances;
    // Official record of token balances for each account
    mapping(address => uint96) internal balances;
    /// @notice A record of each accounts delegate
    mapping(address => address) public delegates;
    /// @notice A checkpoint for marking number of votes from a given block
    struct Checkpoint {
        uint32 fromBlock;
        uint96 votes;
    }
    /// @notice A record of votes checkpoints for each account, by index
    mapping(address => mapping(uint32 => Checkpoint)) public checkpoints;
    /// @notice The number of checkpoints for each account
    mapping(address => uint32) public numCheckpoints;
    /// @notice The EIP-712 typehash for the contract's domain
    bytes32 public constant DOMAIN_TYPEHASH =
        keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");
    /// @notice The EIP-712 typehash for the delegation struct used by the contract
    bytes32 public constant DELEGATION_TYPEHASH =
        keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)");
    /// @notice A record of states for signing / validating signatures
    mapping(address => uint256) public nonces;
    /// @notice Owner address which can upgrade the tokens implementation
    address public owner;
    /// @notice Emitted when the ownership of the contract is transferred
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /// @notice An event thats emitted when an account changes its delegate
    event DelegateChanged(
        address indexed delegator,
        address indexed fromDelegate,
        address indexed toDelegate
    );
    /// @notice An event thats emitted when a delegate account's vote balance changes
    event DelegateVotesChanged(
        address indexed delegate,
        uint256 previousBalance,
        uint256 newBalance
    );
    /// @notice The standard EIP-20 transfer event
    event Transfer(address indexed from, address indexed to, uint256 amount);
    /// @notice The standard EIP-20 approval event
    event Approval(address indexed owner, address indexed spender, uint256 amount);
    constructor() initializer {
        // Making the constructor also an initializer will lock everyone
        // from calling initialize on the implementation contract.
    }
    /// @notice Initialize note token with initial grants
    /// @param initialAccounts initial address to grant tokens to
    /// @param initialGrantAmount amount to grant address initially
    function initialize(
        address[] calldata initialAccounts,
        uint96[] calldata initialGrantAmount,
        address owner_
    ) public initializer {
        require(initialGrantAmount.length == initialAccounts.length);
        uint96 totalGrants = 0;
        for (uint256 i = 0; i < initialGrantAmount.length; i++) {
            totalGrants = _add96(totalGrants, initialGrantAmount[i], "");
            require(balances[initialAccounts[i]] == 0, "Duplicate account");
            balances[initialAccounts[i]] = initialGrantAmount[i];
            emit Transfer(address(0), initialAccounts[i], initialGrantAmount[i]);
        }
        require(totalGrants == totalSupply);
        owner = owner_;
    }
    modifier onlyOwner() {
        require(owner == msg.sender, "Ownable: caller is not the owner");
        _;
    }
    /// @dev Transfers ownership of the contract to a new account (`newOwner`).
    /// Can only be called by the current owner.
    function transferOwnership(address newOwner) external onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }
    /// @dev Only the owner may upgrade the contract
    function _authorizeUpgrade(address newImplementation) internal override onlyOwner { }
    /// @notice Get the number of tokens `spender` is approved to spend on behalf of `account`
    /// @param account The address of the account holding the funds
    /// @param spender The address of the account spending the funds
    /// @return The number of tokens approved
    function allowance(address account, address spender) external view returns (uint256) {
        return allowances[account][spender];
    }
    /// @notice Approve `spender` to transfer up to `amount` from `src`
    /// @dev This will overwrite the approval amount for `spender`
    ///  and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
    ///  emit:Approval
    /// @param spender The address of the account which may transfer tokens
    /// @param rawAmount The number of tokens that are approved (2^256-1 means infinite)
    /// @return Whether or not the approval succeeded
    function approve(address spender, uint256 rawAmount) external returns (bool) {
        uint96 amount;
        if (rawAmount >= type(uint96).max) {
            amount = type(uint96).max;
        } else {
            amount = _safe96(rawAmount, "Note::approve: amount exceeds 96 bits");
        }
        allowances[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }
    /// @notice Get the number of tokens held by the `account`
    /// @param account The address of the account to get the balance of
    /// @return The number of tokens held
    function balanceOf(address account) external view returns (uint256) {
        return balances[account];
    }
    /// @notice Transfer `amount` tokens from `msg.sender` to `dst`
    /// @dev emit:Transfer
    /// @param dst The address of the destination account
    /// @param rawAmount The number of tokens to transfer
    /// @return Whether or not the transfer succeeded
    function transfer(address dst, uint256 rawAmount) external returns (bool) {
        uint96 amount = _safe96(rawAmount, "Note::transfer: amount exceeds 96 bits");
        _transferTokens(msg.sender, dst, amount);
        return true;
    }
    /// @notice Transfer `amount` tokens from `src` to `dst`
    /// @dev emit:Transfer emit:Approval
    /// @param src The address of the source account
    /// @param dst The address of the destination account
    /// @param rawAmount The number of tokens to transfer
    /// @return Whether or not the transfer succeeded
    function transferFrom(
        address src,
        address dst,
        uint256 rawAmount
    ) external returns (bool) {
        // Short circuit transfer execution and return true. It may be the case that external
        // logic tries to execute a zero transfer but don't emit events here.
        if (rawAmount == 0) {
            // Emit a zero transfer event for ERC20 token compatibility
            emit Transfer(src, dst, 0);
            return true;
        }
        address spender = msg.sender;
        uint96 spenderAllowance = allowances[src][spender];
        uint96 amount = _safe96(rawAmount, "Note::approve: amount exceeds 96 bits");
        if (spender != src) {
            uint96 newAllowance =
                _sub96(
                    spenderAllowance,
                    amount,
                    "Note::transferFrom: transfer amount exceeds spender allowance"
                );
            allowances[src][spender] = newAllowance;
        }
        _transferTokens(src, dst, amount);
        return true;
    }
    /// @notice Delegate votes from `msg.sender` to `delegatee`
    /// @param delegatee The address to delegate votes to
    /// @dev emit:DelegatesChanged
    function delegate(address delegatee) public {
        _delegate(msg.sender, delegatee);
    }
    /// @notice Delegates votes from signatory to `delegatee`
    /// @dev emit:DelegatesChanged
    /// @param delegatee The address to delegate votes to
    /// @param nonce The contract state required to match the signature
    /// @param expiry The time at which to expire the signature
    /// @param v The recovery byte of the signature
    /// @param r Half of the ECDSA signature pair
    /// @param s Half of the ECDSA signature pair
    function delegateBySig(
        address delegatee,
        uint256 nonce,
        uint256 expiry,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public {
        require(block.timestamp <= expiry, "Note::delegateBySig: signature expired");
        bytes32 domainSeparator =
            keccak256(
                abi.encode(DOMAIN_TYPEHASH, keccak256(bytes(name)), _getChainId(), address(this))
            );
        bytes32 structHash = keccak256(abi.encode(DELEGATION_TYPEHASH, delegatee, nonce, expiry));
        bytes32 digest = keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
        // ECDSA will check if address is zero inside
        address signatory = ECDSA.recover(digest, v, r, s);
        require(nonce == nonces[signatory]++, "Note::delegateBySig: invalid nonce");
        _delegate(signatory, delegatee);
    }
    /// @notice Gets the current votes balance for `account`
    /// @param account The address to get votes balance
    /// @return The number of current votes for `account`
    function getCurrentVotes(address account) external view returns (uint96) {
        uint32 nCheckpoints = numCheckpoints[account];
        uint96 currentVotes = nCheckpoints > 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;
        return currentVotes;
    }
    /// @notice Determine the prior number of votes for an account as of a block number
    /// @dev Block number must be a finalized block or else this function will revert to prevent misinformation.
    /// @param account The address of the account to check
    /// @param blockNumber The block number to get the vote balance at
    /// @return The number of votes the account had as of the given block
    function getPriorVotes(address account, uint256 blockNumber) public view returns (uint96) {
        require(blockNumber < block.number, "Note::getPriorVotes: not yet determined");
        uint32 nCheckpoints = numCheckpoints[account];
        if (nCheckpoints == 0) {
            return 0;
        }
        // First check most recent balance
        if (checkpoints[account][nCheckpoints - 1].fromBlock <= blockNumber) {
            return checkpoints[account][nCheckpoints - 1].votes;
        }
        // Next check implicit zero balance
        if (checkpoints[account][0].fromBlock > blockNumber) {
            return 0;
        }
        uint32 lower = 0;
        uint32 upper = nCheckpoints - 1;
        while (upper > lower) {
            uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow
            Checkpoint memory cp = checkpoints[account][center];
            if (cp.fromBlock == blockNumber) {
                return cp.votes;
            } else if (cp.fromBlock < blockNumber) {
                lower = center;
            } else {
                upper = center - 1;
            }
        }
        return checkpoints[account][lower].votes;
    }
    /// @dev Changes delegates from one address to another
    function _delegate(address delegator, address delegatee) internal {
        address currentDelegate = delegates[delegator];
        uint96 delegatorBalance = balances[delegator];
        delegates[delegator] = delegatee;
        emit DelegateChanged(delegator, currentDelegate, delegatee);
        _moveDelegates(currentDelegate, delegatee, delegatorBalance);
    }
    /// @dev Transfers tokens and inherits the delegate from the destination address
    function _transferTokens(
        address src,
        address dst,
        uint96 amount
    ) internal {
        require(src != address(0), "Note::_transferTokens: cannot transfer from the zero address");
        require(dst != address(0), "Note::_transferTokens: cannot transfer to the zero address");
        balances[src] = _sub96(
            balances[src],
            amount,
            "Note::_transferTokens: transfer amount exceeds balance"
        );
        balances[dst] = _add96(
            balances[dst],
            amount,
            "Note::_transferTokens: transfer amount overflows"
        );
        emit Transfer(src, dst, amount);
        _moveDelegates(delegates[src], delegates[dst], amount);
    }
    /// @dev Transfers delegates and writes a checkpoint for `getPriorVotes` to use
    function _moveDelegates(
        address srcRep,
        address dstRep,
        uint96 amount
    ) internal {
        if (srcRep != dstRep && amount > 0) {
            if (srcRep != address(0)) {
                uint32 srcRepNum = numCheckpoints[srcRep];
                uint96 srcRepOld = srcRepNum > 0 ? checkpoints[srcRep][srcRepNum - 1].votes : 0;
                uint96 srcRepNew =
                    _sub96(srcRepOld, amount, "Note::_moveVotes: vote amount underflow");
                _writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);
            }
            if (dstRep != address(0)) {
                uint32 dstRepNum = numCheckpoints[dstRep];
                uint96 dstRepOld = dstRepNum > 0 ? checkpoints[dstRep][dstRepNum - 1].votes : 0;
                uint96 dstRepNew =
                    _add96(dstRepOld, amount, "Note::_moveVotes: vote amount overflows");
                _writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);
            }
        }
    }
    /// @dev Writes checkpoints for `getPriorVotes`, this is somewhat inefficient as it uses
    /// 20000 gas per transfer of delegated tokens. The goal is prevent voters from borrowing
    /// a large number of votes for a short period to vote for or against a proposal. It's unclear
    /// if there is a better model than this one here. Using only a single checkpoint means that
    /// a delegate could be the victim of a denial of service attack where an attacker continually
    /// transfers tokens to them to prevent them from voting.
    function _writeCheckpoint(
        address delegatee,
        uint32 nCheckpoints,
        uint96 oldVotes,
        uint96 newVotes
    ) internal {
        uint32 blockNumber =
            _safe32(block.number, "Note::_writeCheckpoint: block number exceeds 32 bits");
        if (nCheckpoints > 0 && checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber) {
            checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;
        } else {
            checkpoints[delegatee][nCheckpoints] = Checkpoint(blockNumber, newVotes);
            numCheckpoints[delegatee] = nCheckpoints + 1;
        }
        emit DelegateVotesChanged(delegatee, oldVotes, newVotes);
    }
    function _safe32(uint256 n, string memory errorMessage) private pure returns (uint32) {
        require(n <= type(uint32).max, errorMessage);
        return uint32(n);
    }
    function _safe96(uint256 n, string memory errorMessage) private pure returns (uint96) {
        require(n <= type(uint96).max, errorMessage);
        return uint96(n);
    }
    function _add96(
        uint96 a,
        uint96 b,
        string memory errorMessage
    ) private pure returns (uint96) {
        uint96 c = a + b;
        require(c >= a, errorMessage);
        return c;
    }
    function _sub96(
        uint96 a,
        uint96 b,
        string memory errorMessage
    ) private pure returns (uint96) {
        require(b <= a, errorMessage);
        return a - b;
    }
    function _getChainId() private pure returns (uint256) {
        uint256 chainId;
        assembly {
            chainId := chainid()
        }
        return chainId;
    }
}
// SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.7.0;
pragma abicoder v2;
import "../../contracts/global/Types.sol";
import "./nTokenERC20.sol";
import "./nERC1155Interface.sol";
import "./NotionalGovernance.sol";
import "./NotionalViews.sol";
interface NotionalProxy is nTokenERC20, nERC1155Interface, NotionalGovernance, NotionalViews {
    /** User trading events */
    event CashBalanceChange(address indexed account, uint16 indexed currencyId, int256 netCashChange);
    event nTokenSupplyChange(address indexed account, uint16 indexed currencyId, int256 tokenSupplyChange);
    event MarketsInitialized(uint16 currencyId);
    event SweepCashIntoMarkets(uint16 currencyId, int256 cashIntoMarkets);
    event SettledCashDebt(
        address indexed settledAccount,
        uint16 indexed currencyId,
        int256 amountToSettleAsset,
        int256 fCashAmount
    );
    event nTokenResidualPurchase(
        uint16 indexed currencyId,
        uint40 indexed maturity,
        int256 fCashAmountToPurchase,
        int256 netAssetCashNToken
    );
    event LendBorrowTrade(
        address indexed account,
        uint16 indexed currencyId,
        uint40 maturity,
        int256 netAssetCash,
        int256 netfCash
    );
    event AddRemoveLiquidity(
        address indexed account,
        uint16 indexed currencyId,
        uint40 maturity,
        int256 netAssetCash,
        int256 netfCash,
        int256 netLiquidityTokens
    );
    /// @notice Emitted when reserve fees are accrued
    event ReserveFeeAccrued(uint16 indexed currencyId, int256 fee);
    /// @notice Emitted whenever an account context has updated
    event AccountContextUpdate(address indexed account);
    /// @notice Emitted when an account has assets that are settled
    event AccountSettled(address indexed account);
    /// @notice Emitted when an asset rate is settled
    event SetSettlementRate(uint256 indexed currencyId, uint256 indexed maturity, uint128 rate);
    /* Liquidation Events */
    event LiquidateLocalCurrency(
        address indexed liquidated,
        address indexed liquidator,
        uint16 localCurrencyId,
        int256 netLocalFromLiquidator
    );
    event LiquidateCollateralCurrency(
        address indexed liquidated,
        address indexed liquidator,
        uint16 localCurrencyId,
        uint16 collateralCurrencyId,
        int256 netLocalFromLiquidator,
        int256 netCollateralTransfer,
        int256 netNTokenTransfer
    );
    event LiquidatefCashEvent(
        address indexed liquidated,
        uint16 localCurrencyId,
        uint16 fCashCurrency,
        int256 netLocalFromLiquidator,
        uint256[] fCashMaturities,
        int256[] fCashNotionalTransfer
    );
    /** UUPS Upgradeable contract calls */
    function upgradeTo(address newImplementation) external;
    function upgradeToAndCall(address newImplementation, bytes memory data) external payable;
    function getImplementation() external view returns (address);
    function owner() external view returns (address);
    function pauseRouter() external view returns (address);
    function pauseGuardian() external view returns (address);
    /** Initialize Markets Action */
    function initializeMarkets(uint16 currencyId, bool isFirstInit) external;
    function sweepCashIntoMarkets(uint16 currencyId) external;
    /** Redeem nToken Action */
    function nTokenRedeem(
        address redeemer,
        uint16 currencyId,
        uint96 tokensToRedeem_,
        bool sellTokenAssets
    ) external returns (int256);
    /** Account Action */
    function enableBitmapCurrency(uint16 currencyId) external;
    function settleAccount(address account) external;
    function depositUnderlyingToken(
        address account,
        uint16 currencyId,
        uint256 amountExternalPrecision
    ) external payable returns (uint256);
    function depositAssetToken(
        address account,
        uint16 currencyId,
        uint256 amountExternalPrecision
    ) external returns (uint256);
    function withdraw(
        uint16 currencyId,
        uint88 amountInternalPrecision,
        bool redeemToUnderlying
    ) external returns (uint256);
    /** Batch Action */
    function batchBalanceAction(address account, BalanceAction[] calldata actions) external payable;
    function batchBalanceAndTradeAction(address account, BalanceActionWithTrades[] calldata actions)
        external
        payable;
    function batchBalanceAndTradeActionWithCallback(
        address account,
        BalanceActionWithTrades[] calldata actions,
        bytes calldata callbackData
    ) external payable;
    /** Liquidation Action */
    function calculateLocalCurrencyLiquidation(
        address liquidateAccount,
        uint16 localCurrency,
        uint96 maxNTokenLiquidation
    ) external returns (int256, int256);
    function liquidateLocalCurrency(
        address liquidateAccount,
        uint16 localCurrency,
        uint96 maxNTokenLiquidation
    ) external returns (int256, int256);
    function calculateCollateralCurrencyLiquidation(
        address liquidateAccount,
        uint16 localCurrency,
        uint16 collateralCurrency,
        uint128 maxCollateralLiquidation,
        uint96 maxNTokenLiquidation
    )
        external
        returns (
            int256,
            int256,
            int256
        );
    function liquidateCollateralCurrency(
        address liquidateAccount,
        uint16 localCurrency,
        uint16 collateralCurrency,
        uint128 maxCollateralLiquidation,
        uint96 maxNTokenLiquidation,
        bool withdrawCollateral,
        bool redeemToUnderlying
    )
        external
        returns (
            int256,
            int256,
            int256
        );
    function calculatefCashLocalLiquidation(
        address liquidateAccount,
        uint16 localCurrency,
        uint256[] calldata fCashMaturities,
        uint256[] calldata maxfCashLiquidateAmounts
    ) external returns (int256[] memory, int256);
    function liquidatefCashLocal(
        address liquidateAccount,
        uint16 localCurrency,
        uint256[] calldata fCashMaturities,
        uint256[] calldata maxfCashLiquidateAmounts
    ) external returns (int256[] memory, int256);
    function calculatefCashCrossCurrencyLiquidation(
        address liquidateAccount,
        uint16 localCurrency,
        uint16 fCashCurrency,
        uint256[] calldata fCashMaturities,
        uint256[] calldata maxfCashLiquidateAmounts
    ) external returns (int256[] memory, int256);
    function liquidatefCashCrossCurrency(
        address liquidateAccount,
        uint16 localCurrency,
        uint16 fCashCurrency,
        uint256[] calldata fCashMaturities,
        uint256[] calldata maxfCashLiquidateAmounts
    ) external returns (int256[] memory, int256);
}
// SPDX-License-Identifier: MIT
// solhint-disable-next-line compiler-version
pragma solidity >=0.4.24 <0.8.0;
import "../utils/Address.sol";
/**
 * @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 !Address.isContract(address(this));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        // Check the signature length
        if (signature.length != 65) {
            revert("ECDSA: invalid signature length");
        }
        // Divide the signature in r, s and v variables
        bytes32 r;
        bytes32 s;
        uint8 v;
        // ecrecover takes the signature parameters, and the only way to get them
        // currently is to use assembly.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := byte(0, mload(add(signature, 0x60)))
        }
        return recover(hash, v, r, s);
    }
    /**
     * @dev Overload of {ECDSA-recover-bytes32-bytes-} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        require(uint256(s) <= 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0, "ECDSA: invalid signature 's' value");
        require(v == 27 || v == 28, "ECDSA: invalid signature 'v' value");
        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        require(signer != address(0), "ECDSA: invalid signature");
        return signer;
    }
    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * replicates the behavior of the
     * https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_sign[`eth_sign`]
     * JSON-RPC method.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
32", hash));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "../ERC1967/ERC1967Upgrade.sol";
/**
 * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
 * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
 *
 * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
 * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
 * `UUPSUpgradeable` with a custom implementation of upgrades.
 *
 * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
 *
 * _Available since v4.1._
 */
abstract contract UUPSUpgradeable is ERC1967Upgrade {
    /**
     * @dev Upgrade the implementation of the proxy to `newImplementation`.
     *
     * Calls {_authorizeUpgrade}.
     *
     * Emits an {Upgraded} event.
     */
    function upgradeTo(address newImplementation) external virtual {
        _authorizeUpgrade(newImplementation);
        _upgradeToAndCallSecure(newImplementation, bytes(""), false);
    }
    /**
     * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
     * encoded in `data`.
     *
     * Calls {_authorizeUpgrade}.
     *
     * Emits an {Upgraded} event.
     */
    function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual {
        _authorizeUpgrade(newImplementation);
        _upgradeToAndCallSecure(newImplementation, data, true);
    }
    /**
     * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
     * {upgradeTo} and {upgradeToAndCall}.
     *
     * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
     *
     * ```solidity
     * function _authorizeUpgrade(address) internal override onlyOwner {}
     * ```
     */
    function _authorizeUpgrade(address newImplementation) internal virtual;
}
// SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.7.0;
pragma abicoder v2;
import "interfaces/chainlink/AggregatorV2V3Interface.sol";
import "interfaces/notional/AssetRateAdapter.sol";
/// @notice Different types of internal tokens
///  - UnderlyingToken: underlying asset for a cToken (except for Ether)
///  - cToken: Compound interest bearing token
///  - cETH: Special handling for cETH tokens
///  - Ether: the one and only
///  - NonMintable: tokens that do not have an underlying (therefore not cTokens)
enum TokenType {UnderlyingToken, cToken, cETH, Ether, NonMintable}
/// @notice Specifies the different trade action types in the system. Each trade action type is
/// encoded in a tightly packed bytes32 object. Trade action type is the first big endian byte of the
/// 32 byte trade action object. The schemas for each trade action type are defined below.
enum TradeActionType {
    // (uint8 TradeActionType, uint8 MarketIndex, uint88 fCashAmount, uint32 minImpliedRate, uint120 unused)
    Lend,
    // (uint8 TradeActionType, uint8 MarketIndex, uint88 fCashAmount, uint32 maxImpliedRate, uint128 unused)
    Borrow,
    // (uint8 TradeActionType, uint8 MarketIndex, uint88 assetCashAmount, uint32 minImpliedRate, uint32 maxImpliedRate, uint88 unused)
    AddLiquidity,
    // (uint8 TradeActionType, uint8 MarketIndex, uint88 tokenAmount, uint32 minImpliedRate, uint32 maxImpliedRate, uint88 unused)
    RemoveLiquidity,
    // (uint8 TradeActionType, uint32 Maturity, int88 fCashResidualAmount, uint128 unused)
    PurchaseNTokenResidual,
    // (uint8 TradeActionType, address CounterpartyAddress, int88 fCashAmountToSettle)
    SettleCashDebt
}
/// @notice Specifies different deposit actions that can occur during BalanceAction or BalanceActionWithTrades
enum DepositActionType {
    // No deposit action
    None,
    // Deposit asset cash, depositActionAmount is specified in asset cash external precision
    DepositAsset,
    // Deposit underlying tokens that are mintable to asset cash, depositActionAmount is specified in underlying token
    // external precision
    DepositUnderlying,
    // Deposits specified asset cash external precision amount into an nToken and mints the corresponding amount of
    // nTokens into the account
    DepositAssetAndMintNToken,
    // Deposits specified underlying in external precision, mints asset cash, and uses that asset cash to mint nTokens
    DepositUnderlyingAndMintNToken,
    // Redeems an nToken balance to asset cash. depositActionAmount is specified in nToken precision. Considered a deposit action
    // because it deposits asset cash into an account. If there are fCash residuals that cannot be sold off, will revert.
    RedeemNToken,
    // Converts specified amount of asset cash balance already in Notional to nTokens. depositActionAmount is specified in
    // Notional internal 8 decimal precision.
    ConvertCashToNToken
}
/// @notice Used internally for PortfolioHandler state
enum AssetStorageState {NoChange, Update, Delete, RevertIfStored}
/****** Calldata objects ******/
/// @notice Defines a balance action for batchAction
struct BalanceAction {
    // Deposit action to take (if any)
    DepositActionType actionType;
    uint16 currencyId;
    // Deposit action amount must correspond to the depositActionType, see documentation above.
    uint256 depositActionAmount;
    // Withdraw an amount of asset cash specified in Notional internal 8 decimal precision
    uint256 withdrawAmountInternalPrecision;
    // If set to true, will withdraw entire cash balance. Useful if there may be an unknown amount of asset cash
    // residual left from trading.
    bool withdrawEntireCashBalance;
    // If set to true, will redeem asset cash to the underlying token on withdraw.
    bool redeemToUnderlying;
}
/// @notice Defines a balance action with a set of trades to do as well
struct BalanceActionWithTrades {
    DepositActionType actionType;
    uint16 currencyId;
    uint256 depositActionAmount;
    uint256 withdrawAmountInternalPrecision;
    bool withdrawEntireCashBalance;
    bool redeemToUnderlying;
    // Array of tightly packed 32 byte objects that represent trades. See TradeActionType documentation
    bytes32[] trades;
}
/****** In memory objects ******/
/// @notice Internal object that represents settled cash balances
struct SettleAmount {
    uint256 currencyId;
    int256 netCashChange;
}
/// @notice Internal object that represents a token
struct Token {
    address tokenAddress;
    bool hasTransferFee;
    int256 decimals;
    TokenType tokenType;
    uint256 maxCollateralBalance;
}
/// @notice Internal object that represents an nToken portfolio
struct nTokenPortfolio {
    CashGroupParameters cashGroup;
    PortfolioState portfolioState;
    int256 totalSupply;
    int256 cashBalance;
    uint256 lastInitializedTime;
    bytes6 parameters;
    address tokenAddress;
}
/// @notice Internal object used during liquidation
struct LiquidationFactors {
    address account;
    // Aggregate free collateral of the account denominated in ETH underlying, 8 decimal precision
    int256 netETHValue;
    // Amount of net local currency asset cash before haircuts and buffers available
    int256 localAssetAvailable;
    // Amount of net collateral currency asset cash before haircuts and buffers available
    int256 collateralAssetAvailable;
    // Haircut value of nToken holdings denominated in asset cash, will be local or collateral nTokens based
    // on liquidation type
    int256 nTokenHaircutAssetValue;
    // nToken parameters for calculating liquidation amount
    bytes6 nTokenParameters;
    // ETH exchange rate from local currency to ETH
    ETHRate localETHRate;
    // ETH exchange rate from collateral currency to ETH
    ETHRate collateralETHRate;
    // Asset rate for the local currency, used in cross currency calculations to calculate local asset cash required
    AssetRateParameters localAssetRate;
    // Used during currency liquidations if the account has liquidity tokens
    CashGroupParameters cashGroup;
    // Used during currency liquidations if it is only a calculation, defaults to false
    bool isCalculation;
}
/// @notice Internal asset array portfolio state
struct PortfolioState {
    // Array of currently stored assets
    PortfolioAsset[] storedAssets;
    // Array of new assets to add
    PortfolioAsset[] newAssets;
    uint256 lastNewAssetIndex;
    // Holds the length of stored assets after accounting for deleted assets
    uint256 storedAssetLength;
}
/// @notice In memory ETH exchange rate used during free collateral calculation.
struct ETHRate {
    // The decimals (i.e. 10^rateDecimalPlaces) of the exchange rate, defined by the rate oracle
    int256 rateDecimals;
    // The exchange rate from base to ETH (if rate invert is required it is already done)
    int256 rate;
    // Amount of buffer as a multiple with a basis of 100 applied to negative balances.
    int256 buffer;
    // Amount of haircut as a multiple with a basis of 100 applied to positive balances
    int256 haircut;
    // Liquidation discount as a multiple with a basis of 100 applied to the exchange rate
    // as an incentive given to liquidators.
    int256 liquidationDiscount;
}
/// @notice Internal object used to handle balance state during a transaction
struct BalanceState {
    uint16 currencyId;
    // Cash balance stored in balance state at the beginning of the transaction
    int256 storedCashBalance;
    // nToken balance stored at the beginning of the transaction
    int256 storedNTokenBalance;
    // The net cash change as a result of asset settlement or trading
    int256 netCashChange;
    // Net asset transfers into or out of the account
    int256 netAssetTransferInternalPrecision;
    // Net token transfers into or out of the account
    int256 netNTokenTransfer;
    // Net token supply change from minting or redeeming
    int256 netNTokenSupplyChange;
    // The last time incentives were claimed for this currency
    uint256 lastClaimTime;
    // The last integral supply amount when tokens were claimed
    uint256 lastClaimIntegralSupply;
}
/// @dev Asset rate used to convert between underlying cash and asset cash
struct AssetRateParameters {
    // Address of the asset rate oracle
    AssetRateAdapter rateOracle;
    // The exchange rate from base to quote (if invert is required it is already done)
    int256 rate;
    // The decimals of the underlying, the rate converts to the underlying decimals
    int256 underlyingDecimals;
}
/// @dev Cash group when loaded into memory
struct CashGroupParameters {
    uint16 currencyId;
    uint256 maxMarketIndex;
    AssetRateParameters assetRate;
    bytes32 data;
}
/// @dev A portfolio asset when loaded in memory
struct PortfolioAsset {
    // Asset currency id
    uint256 currencyId;
    uint256 maturity;
    // Asset type, fCash or liquidity token.
    uint256 assetType;
    // fCash amount or liquidity token amount
    int256 notional;
    // Used for managing portfolio asset state
    uint256 storageSlot;
    // The state of the asset for when it is written to storage
    AssetStorageState storageState;
}
/// @dev Market object as represented in memory
struct MarketParameters {
    bytes32 storageSlot;
    uint256 maturity;
    // Total amount of fCash available for purchase in the market.
    int256 totalfCash;
    // Total amount of cash available for purchase in the market.
    int256 totalAssetCash;
    // Total amount of liquidity tokens (representing a claim on liquidity) in the market.
    int256 totalLiquidity;
    // This is the previous annualized interest rate in RATE_PRECISION that the market traded
    // at. This is used to calculate the rate anchor to smooth interest rates over time.
    uint256 lastImpliedRate;
    // Time lagged version of lastImpliedRate, used to value fCash assets at market rates while
    // remaining resistent to flash loan attacks.
    uint256 oracleRate;
    // This is the timestamp of the previous trade
    uint256 previousTradeTime;
}
/****** Storage objects ******/
/// @dev Token object in storage:
///  20 bytes for token address
///  1 byte for hasTransferFee
///  1 byte for tokenType
///  1 byte for tokenDecimals
///  9 bytes for maxCollateralBalance (may not always be set)
struct TokenStorage {
    // Address of the token
    address tokenAddress;
    // Transfer fees will change token deposit behavior
    bool hasTransferFee;
    TokenType tokenType;
    uint8 decimalPlaces;
    // Upper limit on how much of this token the contract can hold at any time
    uint72 maxCollateralBalance;
}
/// @dev Exchange rate object as it is represented in storage, total storage is 25 bytes.
struct ETHRateStorage {
    // Address of the rate oracle
    AggregatorV2V3Interface rateOracle;
    // The decimal places of precision that the rate oracle uses
    uint8 rateDecimalPlaces;
    // True of the exchange rate must be inverted
    bool mustInvert;
    // NOTE: both of these governance values are set with BUFFER_DECIMALS precision
    // Amount of buffer to apply to the exchange rate for negative balances.
    uint8 buffer;
    // Amount of haircut to apply to the exchange rate for positive balances
    uint8 haircut;
    // Liquidation discount in percentage point terms, 106 means a 6% discount
    uint8 liquidationDiscount;
}
/// @dev Asset rate oracle object as it is represented in storage, total storage is 21 bytes.
struct AssetRateStorage {
    // Address of the rate oracle
    AssetRateAdapter rateOracle;
    // The decimal places of the underlying asset
    uint8 underlyingDecimalPlaces;
}
/// @dev Governance parameters for a cash group, total storage is 9 bytes + 7 bytes for liquidity token haircuts
/// and 7 bytes for rate scalars, total of 23 bytes. Note that this is stored packed in the storage slot so there
/// are no indexes stored for liquidityTokenHaircuts or rateScalars, maxMarketIndex is used instead to determine the
/// length.
struct CashGroupSettings {
    // Index of the AMMs on chain that will be made available. Idiosyncratic fCash
    // that is dated less than the longest AMM will be tradable.
    uint8 maxMarketIndex;
    // Time window in minutes that the rate oracle will be averaged over
    uint8 rateOracleTimeWindowMin;
    // Total fees per trade, specified in BPS
    uint8 totalFeeBPS;
    // Share of the fees given to the protocol, denominated in percentage
    uint8 reserveFeeShare;
    // Debt buffer specified in 5 BPS increments
    uint8 debtBuffer5BPS;
    // fCash haircut specified in 5 BPS increments
    uint8 fCashHaircut5BPS;
    // If an account has a negative cash balance, it can be settled by incurring debt at the 3 month market. This
    // is the basis points for the penalty rate that will be added the current 3 month oracle rate.
    uint8 settlementPenaltyRate5BPS;
    // If an account has fCash that is being liquidated, this is the discount that the liquidator can purchase it for
    uint8 liquidationfCashHaircut5BPS;
    // If an account has fCash that is being liquidated, this is the discount that the liquidator can purchase it for
    uint8 liquidationDebtBuffer5BPS;
    // Liquidity token haircut applied to cash claims, specified as a percentage between 0 and 100
    uint8[] liquidityTokenHaircuts;
    // Rate scalar used to determine the slippage of the market
    uint8[] rateScalars;
}
/// @dev Holds account level context information used to determine settlement and
/// free collateral actions. Total storage is 28 bytes
struct AccountContext {
    // Used to check when settlement must be triggered on an account
    uint40 nextSettleTime;
    // For lenders that never incur debt, we use this flag to skip the free collateral check.
    bytes1 hasDebt;
    // Length of the account's asset array
    uint8 assetArrayLength;
    // If this account has bitmaps set, this is the corresponding currency id
    uint16 bitmapCurrencyId;
    // 9 total active currencies possible (2 bytes each)
    bytes18 activeCurrencies;
}
/// @dev Holds nToken context information mapped via the nToken address, total storage is
/// 16 bytes
struct nTokenContext {
    // Currency id that the nToken represents
    uint16 currencyId;
    // Annual incentive emission rate denominated in WHOLE TOKENS (multiply by 
    // INTERNAL_TOKEN_PRECISION to get the actual rate)
    uint32 incentiveAnnualEmissionRate;
    // The last block time at utc0 that the nToken was initialized at, zero if it
    // has never been initialized
    uint32 lastInitializedTime;
    // Length of the asset array, refers to the number of liquidity tokens an nToken
    // currently holds
    uint8 assetArrayLength;
    // Each byte is a specific nToken parameter
    bytes5 nTokenParameters;
}
/// @dev Holds account balance information, total storage 32 bytes
struct BalanceStorage {
    // Number of nTokens held by the account
    uint80 nTokenBalance;
    // Last time the account claimed their nTokens
    uint32 lastClaimTime;
    // The total integral supply of the nToken at the last claim time packed into
    // 56 bits. There is some loss of precision here but it is acceptable
    uint56 packedLastClaimIntegralSupply;
    // Cash balance of the account
    int88 cashBalance;
}
/// @dev Holds information about a settlement rate, total storage 25 bytes
struct SettlementRateStorage {
    uint40 blockTime;
    uint128 settlementRate;
    uint8 underlyingDecimalPlaces;
}
/// @dev Holds information about a market, total storage is 42 bytes so this spans
/// two storage words
struct MarketStorage {
    // Total fCash in the market
    uint80 totalfCash;
    // Total asset cash in the market
    uint80 totalAssetCash;
    // Last annualized interest rate the market traded at
    uint32 lastImpliedRate;
    // Last recorded oracle rate for the market
    uint32 oracleRate;
    // Last time a trade was made
    uint32 previousTradeTime;
    // This is stored in slot + 1
    uint80 totalLiquidity;
}
struct ifCashStorage {
    // Notional amount of fCash at the slot, limited to int128 to allow for
    // future expansion
    int128 notional;
}
/// @dev A single portfolio asset in storage, total storage of 19 bytes
struct PortfolioAssetStorage {
    // Currency Id for the asset
    uint16 currencyId;
    // Maturity of the asset
    uint40 maturity;
    // Asset type (fCash or Liquidity Token marker)
    uint8 assetType;
    // Notional
    int88 notional;
}
/// @dev nToken total supply factors for the nToken, includes factors related
/// to claiming incentives, total storage 32 bytes
struct nTokenTotalSupplyStorage {
    // Total supply of the nToken
    uint96 totalSupply;
    // Integral of the total supply used for calculating the average total supply
    uint128 integralTotalSupply;
    // Last timestamp the supply value changed, used for calculating the integralTotalSupply
    uint32 lastSupplyChangeTime;
}
/// @dev Used in view methods to return account balances in a developer friendly manner
struct AccountBalance {
    uint16 currencyId;
    int256 cashBalance;
    int256 nTokenBalance;
    uint256 lastClaimTime;
    uint256 lastClaimIntegralSupply;
}
// SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.7.0;
pragma abicoder v2;
interface nTokenERC20 {
    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
    function nTokenTotalSupply(address nTokenAddress) external view returns (uint256);
    function nTokenTransferAllowance(
        uint16 currencyId,
        address owner,
        address spender
    ) external view returns (uint256);
    function nTokenBalanceOf(uint16 currencyId, address account) external view returns (uint256);
    function nTokenTransferApprove(
        uint16 currencyId,
        address owner,
        address spender,
        uint256 amount
    ) external returns (bool);
    function nTokenTransfer(
        uint16 currencyId,
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
    function nTokenTransferFrom(
        uint16 currencyId,
        address spender,
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
    function nTokenTransferApproveAll(address spender, uint256 amount) external returns (bool);
    function nTokenClaimIncentives() external returns (uint256);
    function nTokenPresentValueAssetDenominated(uint16 currencyId) external view returns (int256);
    function nTokenPresentValueUnderlyingDenominated(uint16 currencyId)
        external
        view
        returns (int256);
}
// SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.7.0;
pragma abicoder v2;
import "../../contracts/global/Types.sol";
interface nERC1155Interface {
    event TransferSingle(
        address indexed operator,
        address indexed from,
        address indexed to,
        uint256 id,
        uint256 value
    );
    event TransferBatch(
        address indexed operator,
        address indexed from,
        address indexed to,
        uint256[] ids,
        uint256[] values
    );
    event ApprovalForAll(address indexed account, address indexed operator, bool approved);
    event URI(string value, uint256 indexed id);
    function supportsInterface(bytes4 interfaceId) external pure returns (bool);
    function balanceOf(address account, uint256 id) external view returns (uint256);
    function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids)
        external
        view
        returns (uint256[] memory);
    function signedBalanceOf(address account, uint256 id) external view returns (int256);
    function signedBalanceOfBatch(address[] calldata accounts, uint256[] calldata ids)
        external
        view
        returns (int256[] memory);
    function setApprovalForAll(address operator, bool approved) external;
    function isApprovedForAll(address account, address operator) external view returns (bool);
    function safeTransferFrom(
        address from,
        address to,
        uint256 id,
        uint256 amount,
        bytes calldata data
    ) external payable;
    function safeBatchTransferFrom(
        address from,
        address to,
        uint256[] calldata ids,
        uint256[] calldata amounts,
        bytes calldata data
    ) external payable;
    function decodeToAssets(uint256[] calldata ids, uint256[] calldata amounts)
        external
        view
        returns (PortfolioAsset[] memory);
    function encodeToId(
        uint16 currencyId,
        uint40 maturity,
        uint8 assetType
    ) external pure returns (uint256 id);
}
// SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.7.0;
pragma abicoder v2;
import "../../contracts/global/Types.sol";
import "interfaces/chainlink/AggregatorV2V3Interface.sol";
import "interfaces/notional/NotionalGovernance.sol";
interface NotionalGovernance {
    event ListCurrency(uint16 newCurrencyId);
    event UpdateETHRate(uint16 currencyId);
    event UpdateAssetRate(uint16 currencyId);
    event UpdateCashGroup(uint16 currencyId);
    event DeployNToken(uint16 currencyId, address nTokenAddress);
    event UpdateDepositParameters(uint16 currencyId);
    event UpdateInitializationParameters(uint16 currencyId);
    event UpdateIncentiveEmissionRate(uint16 currencyId, uint32 newEmissionRate);
    event UpdateTokenCollateralParameters(uint16 currencyId);
    event UpdateGlobalTransferOperator(address operator, bool approved);
    event UpdateAuthorizedCallbackContract(address operator, bool approved);
    event UpdateMaxCollateralBalance(uint16 currencyId, uint72 maxCollateralBalance);
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    event PauseRouterAndGuardianUpdated(address indexed pauseRouter, address indexed pauseGuardian);
    function transferOwnership(address newOwner) external;
    function setPauseRouterAndGuardian(address pauseRouter_, address pauseGuardian_) external;
    function listCurrency(
        TokenStorage calldata assetToken,
        TokenStorage calldata underlyingToken,
        AggregatorV2V3Interface rateOracle,
        bool mustInvert,
        uint8 buffer,
        uint8 haircut,
        uint8 liquidationDiscount
    ) external returns (uint16 currencyId);
    function updateMaxCollateralBalance(
        uint16 currencyId,
        uint72 maxCollateralBalanceInternalPrecision
    ) external;
    function enableCashGroup(
        uint16 currencyId,
        AssetRateAdapter assetRateOracle,
        CashGroupSettings calldata cashGroup,
        string calldata underlyingName,
        string calldata underlyingSymbol
    ) external;
    function updateDepositParameters(
        uint16 currencyId,
        uint32[] calldata depositShares,
        uint32[] calldata leverageThresholds
    ) external;
    function updateInitializationParameters(
        uint16 currencyId,
        uint32[] calldata annualizedAnchorRates,
        uint32[] calldata proportions
    ) external;
    function updateIncentiveEmissionRate(uint16 currencyId, uint32 newEmissionRate) external;
    function updateTokenCollateralParameters(
        uint16 currencyId,
        uint8 residualPurchaseIncentive10BPS,
        uint8 pvHaircutPercentage,
        uint8 residualPurchaseTimeBufferHours,
        uint8 cashWithholdingBuffer10BPS,
        uint8 liquidationHaircutPercentage
    ) external;
    function updateCashGroup(uint16 currencyId, CashGroupSettings calldata cashGroup) external;
    function updateAssetRate(uint16 currencyId, AssetRateAdapter rateOracle) external;
    function updateETHRate(
        uint16 currencyId,
        AggregatorV2V3Interface rateOracle,
        bool mustInvert,
        uint8 buffer,
        uint8 haircut,
        uint8 liquidationDiscount
    ) external;
    function updateGlobalTransferOperator(address operator, bool approved) external;
    function updateAuthorizedCallbackContract(address operator, bool approved) external;
}
// SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.7.0;
pragma abicoder v2;
import "../../contracts/global/Types.sol";
interface NotionalViews {
    function getMaxCurrencyId() external view returns (uint16);
    function getCurrencyId(address tokenAddress) external view returns (uint16 currencyId);
    function getCurrency(uint16 currencyId)
        external
        view
        returns (Token memory assetToken, Token memory underlyingToken);
    function getRateStorage(uint16 currencyId)
        external
        view
        returns (ETHRateStorage memory ethRate, AssetRateStorage memory assetRate);
    function getCurrencyAndRates(uint16 currencyId)
        external
        view
        returns (
            Token memory assetToken,
            Token memory underlyingToken,
            ETHRate memory ethRate,
            AssetRateParameters memory assetRate
        );
    function getCashGroup(uint16 currencyId) external view returns (CashGroupSettings memory);
    function getCashGroupAndAssetRate(uint16 currencyId)
        external
        view
        returns (CashGroupSettings memory cashGroup, AssetRateParameters memory assetRate);
    function getInitializationParameters(uint16 currencyId)
        external
        view
        returns (int256[] memory annualizedAnchorRates, int256[] memory proportions);
    function getDepositParameters(uint16 currencyId)
        external
        view
        returns (int256[] memory depositShares, int256[] memory leverageThresholds);
    function nTokenAddress(uint16 currencyId) external view returns (address);
    function getNoteToken() external view returns (address);
    function getSettlementRate(uint16 currencyId, uint40 maturity)
        external
        view
        returns (AssetRateParameters memory);
    function getMarket(uint16 currencyId, uint256 maturity, uint256 settlementDate)
        external view returns (MarketParameters memory);
    function getActiveMarkets(uint16 currencyId) external view returns (MarketParameters[] memory);
    function getActiveMarketsAtBlockTime(uint16 currencyId, uint32 blockTime)
        external
        view
        returns (MarketParameters[] memory);
    function getReserveBalance(uint16 currencyId) external view returns (int256 reserveBalance);
    function getNTokenPortfolio(address tokenAddress)
        external
        view
        returns (PortfolioAsset[] memory liquidityTokens, PortfolioAsset[] memory netfCashAssets);
    function getNTokenAccount(address tokenAddress)
        external
        view
        returns (
            uint16 currencyId,
            uint256 totalSupply,
            uint256 incentiveAnnualEmissionRate,
            uint256 lastInitializedTime,
            bytes5 nTokenParameters,
            int256 cashBalance,
            uint256 integralTotalSupply,
            uint256 lastSupplyChangeTime
        );
    function getAccount(address account)
        external
        view
        returns (
            AccountContext memory accountContext,
            AccountBalance[] memory accountBalances,
            PortfolioAsset[] memory portfolio
        );
    function getAccountContext(address account) external view returns (AccountContext memory);
    function getAccountBalance(uint16 currencyId, address account)
        external
        view
        returns (
            int256 cashBalance,
            int256 nTokenBalance,
            uint256 lastClaimTime
        );
    function getAccountPortfolio(address account) external view returns (PortfolioAsset[] memory);
    function getfCashNotional(
        address account,
        uint16 currencyId,
        uint256 maturity
    ) external view returns (int256);
    function getAssetsBitmap(address account, uint16 currencyId) external view returns (bytes32);
    function getFreeCollateral(address account) external view returns (int256, int256[] memory);
    function calculateNTokensToMint(uint16 currencyId, uint88 amountToDepositExternalPrecision)
        external
        view
        returns (uint256);
    function getfCashAmountGivenCashAmount(
        uint16 currencyId,
        int88 netCashToAccount,
        uint256 marketIndex,
        uint256 blockTime
    ) external view returns (int256);
    function getCashAmountGivenfCashAmount(
        uint16 currencyId,
        int88 fCashAmount,
        uint256 marketIndex,
        uint256 blockTime
    ) external view returns (int256, int256);
    function nTokenGetClaimableIncentives(address account, uint256 blockTime)
        external
        view
        returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0;
import "./AggregatorInterface.sol";
import "./AggregatorV3Interface.sol";
interface AggregatorV2V3Interface is AggregatorInterface, AggregatorV3Interface
{
}// SPDX-License-Identifier: GPL-v3
pragma solidity >=0.7.0;
/// @notice Used as a wrapper for tokens that are interest bearing for an
/// underlying token. Follows the cToken interface, however, can be adapted
/// for other interest bearing tokens.
interface AssetRateAdapter {
    function token() external view returns (address);
    function decimals() external view returns (uint8);
    function description() external view returns (string memory);
    function version() external view returns (uint256);
    function underlying() external view returns (address);
    function getExchangeRateStateful() external returns (int256);
    function getExchangeRateView() external view returns (int256);
    function getAnnualizedSupplyRate() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0;
interface AggregatorInterface {
  function latestAnswer() external view returns (int256);
  function latestTimestamp() external view returns (uint256);
  function latestRound() external view returns (uint256);
  function getAnswer(uint256 roundId) external view returns (int256);
  function getTimestamp(uint256 roundId) external view returns (uint256);
  event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt);
  event NewRound(uint256 indexed roundId, address indexed startedBy, uint256 startedAt);
}// SPDX-License-Identifier: MIT
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
    );
}// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "@openzeppelin/contracts/utils/Address.sol";
import "../utils/StorageSlot.sol";
/**
 * @dev This abstract contract provides getters and event emitting update functions for
 * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
 *
 * _Available since v4.1._
 *
 */
abstract contract ERC1967Upgrade {
    // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
    bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
    /**
     * @dev Storage slot with the address of the current implementation.
     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
    /**
     * @dev Emitted when the implementation is upgraded.
     */
    event Upgraded(address indexed implementation);
    /**
     * @dev Returns the current implementation address.
     */
    function _getImplementation() internal view returns (address) {
        return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
    }
    /**
     * @dev Stores a new address in the EIP1967 implementation slot.
     */
    function _setImplementation(address newImplementation) private {
        require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
        StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
    }
    /**
     * @dev Perform implementation upgrade
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeTo(address newImplementation) internal {
        _setImplementation(newImplementation);
        emit Upgraded(newImplementation);
    }
    /**
     * @dev Perform implementation upgrade with additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCall(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        _upgradeTo(newImplementation);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(newImplementation, data);
        }
    }
    /**
     * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
     *
     * Emits an {Upgraded} event.
     */
    function _upgradeToAndCallSecure(
        address newImplementation,
        bytes memory data,
        bool forceCall
    ) internal {
        address oldImplementation = _getImplementation();
        // Initial upgrade and setup call
        _setImplementation(newImplementation);
        if (data.length > 0 || forceCall) {
            Address.functionDelegateCall(newImplementation, data);
        }
        // Perform rollback test if not already in progress
        StorageSlot.BooleanSlot storage rollbackTesting = StorageSlot.getBooleanSlot(_ROLLBACK_SLOT);
        if (!rollbackTesting.value) {
            // Trigger rollback using upgradeTo from the new implementation
            rollbackTesting.value = true;
            Address.functionDelegateCall(
                newImplementation,
                abi.encodeWithSignature("upgradeTo(address)", oldImplementation)
            );
            rollbackTesting.value = false;
            // Check rollback was effective
            require(oldImplementation == _getImplementation(), "ERC1967Upgrade: upgrade breaks further upgrades");
            // Finally reset to the new implementation and log the upgrade
            _upgradeTo(newImplementation);
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
 * @dev Library for reading and writing primitive types to specific storage slots.
 *
 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
 * This library helps with reading and writing to such slots without the need for inline assembly.
 *
 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
 *
 * Example usage to set ERC1967 implementation slot:
 * ```
 * contract ERC1967 {
 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
 *
 *     function _getImplementation() internal view returns (address) {
 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
 *     }
 *
 *     function _setImplementation(address newImplementation) internal {
 *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
 *     }
 * }
 * ```
 *
 * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }
    struct BooleanSlot {
        bool value;
    }
    struct Bytes32Slot {
        bytes32 value;
    }
    struct Uint256Slot {
        uint256 value;
    }
    /**
     * @dev Returns an `AddressSlot` with member `value` located at `slot`.
     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        assembly {
            r.slot := slot
        }
    }
    /**
     * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        assembly {
            r.slot := slot
        }
    }
}