// SPDX-License-Identifier: MIT
pragma solidity 0.8.8;

// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

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

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

// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

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

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

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

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

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

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

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

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

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

// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

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

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

// OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)

/**
 * @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
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

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

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

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

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

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

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

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

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

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

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

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

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

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

// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/utils/SafeERC20.sol)

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

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

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

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

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

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

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

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

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

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

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

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

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

// https://github.com/Uniswap/permit2

/// @title SignatureTransfer
/// @notice Handles ERC20 token transfers through signature based actions
/// @dev Requires user's token approval on the Permit2 contract
interface ISignatureTransfer {

    /// @notice The token and amount details for a transfer signed in the permit transfer signature
    struct TokenPermissions {
        // ERC20 token address
        address token;
        // the maximum amount that can be spent
        uint256 amount;
    }

    /// @notice The signed permit message for a single token transfer
    struct PermitTransferFrom {
        TokenPermissions permitted;
        // a unique value for every token owner's signature to prevent signature replays
        uint256 nonce;
        // deadline on the permit signature
        uint256 deadline;
    }

    /// @notice Specifies the recipient address and amount for batched transfers.
    /// @dev Recipients and amounts correspond to the index of the signed token permissions array.
    /// @dev Reverts if the requested amount is greater than the permitted signed amount.
    struct SignatureTransferDetails {
        // recipient address
        address to;
        // spender requested amount
        uint256 requestedAmount;
    }

    /// @notice Used to reconstruct the signed permit message for multiple token transfers
    /// @dev Do not need to pass in spender address as it is required that it is msg.sender
    /// @dev Note that a user still signs over a spender address
    struct PermitBatchTransferFrom {
        // the tokens and corresponding amounts permitted for a transfer
        TokenPermissions[] permitted;
        // a unique value for every token owner's signature to prevent signature replays
        uint256 nonce;
        // deadline on the permit signature
        uint256 deadline;
    }
    /// @notice Transfers a token using a signed permit message
    /// @dev Reverts if the requested amount is greater than the permitted signed amount
    /// @param permit The permit data signed over by the owner
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails The spender's requested transfer details for the permitted token
    /// @param signature The signature to verify
    function permitTransferFrom(
        PermitTransferFrom memory permit,
        SignatureTransferDetails calldata transferDetails,
        address owner,
        bytes calldata signature
    ) external;

    /// @notice Transfers multiple tokens using a signed permit message
    /// @param permit The permit data signed over by the owner
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails Specifies the recipient and requested amount for the token transfer
    /// @param signature The signature to verify
    function permitTransferFrom(
        PermitBatchTransferFrom memory permit,
        SignatureTransferDetails[] calldata transferDetails,
        address owner,
        bytes calldata signature
    ) external;
}

// @dev interface for interacting with an Odos executor
interface IOdosExecutor {
  function executePath (
    bytes calldata bytecode,
    uint256[] memory inputAmount,
    address msgSender
  ) external payable;
}

/// @title Routing contract for Odos SOR
/// @author Semiotic AI
/// @notice Wrapper with security gaurentees around execution of arbitrary operations on user tokens
contract OdosRouterV2 is Ownable {
  using SafeERC20 for IERC20;

  /// @dev The zero address is uniquely used to represent eth since it is already
  /// recognized as an invalid ERC20, and due to its gas efficiency
  address constant _ETH = address(0);

  /// @dev Address list where addresses can be cached for use when reading from storage is cheaper
  // than reading from calldata. addressListStart is the storage slot of the first dynamic array element
  uint256 private constant addressListStart = 
    80084422859880547211683076133703299733277748156566366325829078699459944778998;
  address[] public addressList;

  // @dev constants for managing referrals and fees
  uint256 public constant REFERRAL_WITH_FEE_THRESHOLD = 1 << 31;
  uint256 public constant FEE_DENOM = 1e18;

  // @dev fee taken on multi-input and multi-output swaps instead of positive slippage
  uint256 public swapMultiFee;

  /// @dev Contains all information needed to describe the input and output for a swap
  struct permit2Info {
    address contractAddress;
    uint256 nonce;
    uint256 deadline;
    bytes signature;
  }
  /// @dev Contains all information needed to describe the input and output for a swap
  struct swapTokenInfo {
    address inputToken;
    uint256 inputAmount;
    address inputReceiver;
    address outputToken;
    uint256 outputQuote;
    uint256 outputMin;
    address outputReceiver;
  }
  /// @dev Contains all information needed to describe an intput token for swapMulti
  struct inputTokenInfo {
    address tokenAddress;
    uint256 amountIn;
    address receiver;
  }
  /// @dev Contains all information needed to describe an output token for swapMulti
  struct outputTokenInfo {
    address tokenAddress;
    uint256 relativeValue;
    address receiver;
  }
  // @dev event for swapping one token for another
  event Swap(
    address sender,
    uint256 inputAmount,
    address inputToken,
    uint256 amountOut,
    address outputToken,
    int256 slippage,
    uint32 referralCode
  );
  /// @dev event for swapping multiple input and/or output tokens
  event SwapMulti(
    address sender,
    uint256[] amountsIn,
    address[] tokensIn,
    uint256[] amountsOut,
    address[] tokensOut,
    uint32 referralCode
  );
  /// @dev Holds all information for a given referral
  struct referralInfo {
    uint64 referralFee;
    address beneficiary;
    bool registered;
  }
  /// @dev Register referral fee and information
  mapping(uint32 => referralInfo) public referralLookup;

  /// @dev Set the null referralCode as "Unregistered" with no additional fee
  constructor() {
    referralLookup[0].referralFee = 0;
    referralLookup[0].beneficiary = address(0);
    referralLookup[0].registered = true;

    swapMultiFee = 5e14;
  }
  /// @dev Must exist in order for contract to receive eth
  receive() external payable { }

  /// @notice Custom decoder to swap with compact calldata for efficient execution on L2s
  function swapCompact() 
    external
    payable
    returns (uint256)
  {
    swapTokenInfo memory tokenInfo;

    address executor;
    uint32 referralCode;
    bytes calldata pathDefinition;
    {
      address msgSender = msg.sender;

      assembly {
        // Define function to load in token address, either from calldata or from storage
        function getAddress(currPos) -> result, newPos {
          let inputPos := shr(240, calldataload(currPos))

          switch inputPos
          // Reserve the null address as a special case that can be specified with 2 null bytes
          case 0x0000 {
            newPos := add(currPos, 2)
          }
          // This case means that the address is encoded in the calldata directly following the code
          case 0x0001 {
            result := and(shr(80, calldataload(currPos)), 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF)
            newPos := add(currPos, 22)
          }
          // Otherwise we use the case to load in from the cached address list
          default {
            result := sload(add(addressListStart, sub(inputPos, 2)))
            newPos := add(currPos, 2)
          }
        }
        let result := 0
        let pos := 4

        // Load in the input and output token addresses
        result, pos := getAddress(pos)
        mstore(tokenInfo, result)

        result, pos := getAddress(pos)
        mstore(add(tokenInfo, 0x60), result)

        // Load in the input amount - a 0 byte means the full balance is to be used
        let inputAmountLength := shr(248, calldataload(pos))
        pos := add(pos, 1)

        if inputAmountLength {
          mstore(add(tokenInfo, 0x20), shr(mul(sub(32, inputAmountLength), 8), calldataload(pos)))
          pos := add(pos, inputAmountLength)
        }

        // Load in the quoted output amount
        let quoteAmountLength := shr(248, calldataload(pos))
        pos := add(pos, 1)

        let outputQuote := shr(mul(sub(32, quoteAmountLength), 8), calldataload(pos))
        mstore(add(tokenInfo, 0x80), outputQuote)
        pos := add(pos, quoteAmountLength)

        // Load the slippage tolerance and use to get the minimum output amount
        {
          let slippageTolerance := shr(232, calldataload(pos))
          mstore(add(tokenInfo, 0xA0), div(mul(outputQuote, sub(0xFFFFFF, slippageTolerance)), 0xFFFFFF))
        }
        pos := add(pos, 3)

        // Load in the executor address
        executor, pos := getAddress(pos)

        // Load in the destination to send the input to - Zero denotes the executor
        result, pos := getAddress(pos)
        if eq(result, 0) { result := executor }
        mstore(add(tokenInfo, 0x40), result)

        // Load in the destination to send the output to - Zero denotes msg.sender
        result, pos := getAddress(pos)
        if eq(result, 0) { result := msgSender }
        mstore(add(tokenInfo, 0xC0), result)

        // Load in the referralCode
        referralCode := shr(224, calldataload(pos))
        pos := add(pos, 4)

        // Set the offset and size for the pathDefinition portion of the msg.data
        pathDefinition.length := mul(shr(248, calldataload(pos)), 32)
        pathDefinition.offset := add(pos, 1)
      }
    }
    return _swapApproval(
      tokenInfo,
      pathDefinition,
      executor,
      referralCode
    );
  }
  /// @notice Externally facing interface for swapping two tokens
  /// @param tokenInfo All information about the tokens being swapped
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function swap(
    swapTokenInfo memory tokenInfo,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    external
    payable
    returns (uint256 amountOut)
  {
    return _swapApproval(
      tokenInfo,
      pathDefinition,
      executor,
      referralCode
    );
  }

  /// @notice Internal function for initiating approval transfers
  /// @param tokenInfo All information about the tokens being swapped
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function _swapApproval(
    swapTokenInfo memory tokenInfo,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    internal
    returns (uint256 amountOut)
  {
    if (tokenInfo.inputToken == _ETH) {
      // Support rebasing tokens by allowing the user to trade the entire balance
      if (tokenInfo.inputAmount == 0) {
        tokenInfo.inputAmount = msg.value;
      } else {
        require(msg.value == tokenInfo.inputAmount, "Wrong msg.value");
      }
    }
    else {
      // Support rebasing tokens by allowing the user to trade the entire balance
      if (tokenInfo.inputAmount == 0) {
        tokenInfo.inputAmount = IERC20(tokenInfo.inputToken).balanceOf(msg.sender);
      }
      IERC20(tokenInfo.inputToken).safeTransferFrom(
        msg.sender,
        tokenInfo.inputReceiver,
        tokenInfo.inputAmount
      );
    }
    return _swap(
      tokenInfo,
      pathDefinition,
      executor,
      referralCode
    );
  }

  /// @notice Externally facing interface for swapping two tokens
  /// @param permit2 All additional info for Permit2 transfers
  /// @param tokenInfo All information about the tokens being swapped
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function swapPermit2(
    permit2Info memory permit2,
    swapTokenInfo memory tokenInfo,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    external
    returns (uint256 amountOut)
  {
    ISignatureTransfer(permit2.contractAddress).permitTransferFrom(
      ISignatureTransfer.PermitTransferFrom(
        ISignatureTransfer.TokenPermissions(
          tokenInfo.inputToken,
          tokenInfo.inputAmount
        ),
        permit2.nonce,
        permit2.deadline
      ),
      ISignatureTransfer.SignatureTransferDetails(
        tokenInfo.inputReceiver,
        tokenInfo.inputAmount
      ),
      msg.sender,
      permit2.signature
    );
    return _swap(
      tokenInfo,
      pathDefinition,
      executor,
      referralCode
    );
  }

  /// @notice contains the main logic for swapping one token for another
  /// Assumes input tokens have already been sent to their destinations and
  /// that msg.value is set to expected ETH input value, or 0 for ERC20 input
  /// @param tokenInfo All information about the tokens being swapped
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function _swap(
    swapTokenInfo memory tokenInfo,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    internal
    returns (uint256 amountOut)
  {
    // Check for valid output specifications
    require(tokenInfo.outputMin <= tokenInfo.outputQuote, "Minimum greater than quote");
    require(tokenInfo.outputMin > 0, "Slippage limit too low");
    require(tokenInfo.inputToken != tokenInfo.outputToken, "Arbitrage not supported");

    uint256 balanceBefore = _universalBalance(tokenInfo.outputToken);

    // Delegate the execution of the path to the specified Odos Executor
    uint256[] memory amountsIn = new uint256[](1);
    amountsIn[0] = tokenInfo.inputAmount;

    IOdosExecutor(executor).executePath{value: msg.value}(pathDefinition, amountsIn, msg.sender);

    amountOut = _universalBalance(tokenInfo.outputToken) - balanceBefore;

    if (referralCode > REFERRAL_WITH_FEE_THRESHOLD) {
      referralInfo memory thisReferralInfo = referralLookup[referralCode];

      _universalTransfer(
        tokenInfo.outputToken,
        thisReferralInfo.beneficiary,
        amountOut * thisReferralInfo.referralFee * 8 / (FEE_DENOM * 10)
      );
      amountOut = amountOut * (FEE_DENOM - thisReferralInfo.referralFee) / FEE_DENOM;
    }
    int256 slippage = int256(amountOut) - int256(tokenInfo.outputQuote);
    if (slippage > 0) {
      amountOut = tokenInfo.outputQuote;
    }
    require(amountOut >= tokenInfo.outputMin, "Slippage Limit Exceeded");

    // Transfer out the final output to the end user
    _universalTransfer(tokenInfo.outputToken, tokenInfo.outputReceiver, amountOut);

    emit Swap(
      msg.sender,
      tokenInfo.inputAmount,
      tokenInfo.inputToken,
      amountOut,
      tokenInfo.outputToken,
      slippage,
      referralCode
    );
  }

  /// @notice Custom decoder to swapMulti with compact calldata for efficient execution on L2s
  function swapMultiCompact() 
    external
    payable
    returns (uint256[] memory amountsOut)
  {
    address executor;
    uint256 valueOutMin;

    inputTokenInfo[] memory inputs;
    outputTokenInfo[] memory outputs;

    uint256 pos = 6;
    {
      address msgSender = msg.sender;

      uint256 numInputs;
      uint256 numOutputs;

      assembly {
        numInputs := shr(248, calldataload(4))
        numOutputs := shr(248, calldataload(5))
      }
      inputs = new inputTokenInfo[](numInputs);
      outputs = new outputTokenInfo[](numOutputs);

      assembly {
        // Define function to load in token address, either from calldata or from storage
        function getAddress(currPos) -> result, newPos {
          let inputPos := shr(240, calldataload(currPos))

          switch inputPos
          // Reserve the null address as a special case that can be specified with 2 null bytes
          case 0x0000 {
            newPos := add(currPos, 2)
          }
          // This case means that the address is encoded in the calldata directly following the code
          case 0x0001 {
            result := and(shr(80, calldataload(currPos)), 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF)
            newPos := add(currPos, 22)
          }
          // Otherwise we use the case to load in from the cached address list
          default {
            result := sload(add(addressListStart, sub(inputPos, 2)))
            newPos := add(currPos, 2)
          }
        }
        executor, pos := getAddress(pos)

        // Load in the quoted output amount
        let outputMinAmountLength := shr(248, calldataload(pos))
        pos := add(pos, 1)

        valueOutMin := shr(mul(sub(32, outputMinAmountLength), 8), calldataload(pos))
        pos := add(pos, outputMinAmountLength)

        let result := 0
        let memPos := 0

        for { let element := 0 } lt(element, numInputs) { element := add(element, 1) }
        {
          memPos := mload(add(inputs, add(mul(element, 0x20), 0x20)))

          // Load in the token address
          result, pos := getAddress(pos)
          mstore(memPos, result)

          // Load in the input amount - a 0 byte means the full balance is to be used
          let inputAmountLength := shr(248, calldataload(pos))
          pos := add(pos, 1)

          if inputAmountLength {
             mstore(add(memPos, 0x20), shr(mul(sub(32, inputAmountLength), 8), calldataload(pos)))
            pos := add(pos, inputAmountLength)
          }
          result, pos := getAddress(pos)
          if eq(result, 0) { result := executor }

          mstore(add(memPos, 0x40), result)
        }
        for { let element := 0 } lt(element, numOutputs) { element := add(element, 1) }
        {
          memPos := mload(add(outputs, add(mul(element, 0x20), 0x20)))

          // Load in the token address
          result, pos := getAddress(pos)
          mstore(memPos, result)

          // Load in the quoted output amount
          let outputAmountLength := shr(248, calldataload(pos))
          pos := add(pos, 1)

          mstore(add(memPos, 0x20), shr(mul(sub(32, outputAmountLength), 8), calldataload(pos)))
          pos := add(pos, outputAmountLength)

          result, pos := getAddress(pos)
          if eq(result, 0) { result := msgSender }

          mstore(add(memPos, 0x40), result)
        }
      }
    }
    uint32 referralCode;
    bytes calldata pathDefinition;

    assembly {
      // Load in the referralCode
      referralCode := shr(224, calldataload(pos))
      pos := add(pos, 4)

      // Set the offset and size for the pathDefinition portion of the msg.data
      pathDefinition.length := mul(shr(248, calldataload(pos)), 32)
      pathDefinition.offset := add(pos, 1)
    }
    return _swapMultiApproval(
      inputs,
      outputs,
      valueOutMin,
      pathDefinition,
      executor,
      referralCode
    );
  }

  /// @notice Externally facing interface for swapping between two sets of tokens
  /// @param inputs list of input token structs for the path being executed
  /// @param outputs list of output token structs for the path being executed
  /// @param valueOutMin minimum amount of value out the user will accept
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function swapMulti(
    inputTokenInfo[] memory inputs,
    outputTokenInfo[] memory outputs,
    uint256 valueOutMin,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    external
    payable
    returns (uint256[] memory amountsOut)
  {
    return _swapMultiApproval(
      inputs,
      outputs,
      valueOutMin,
      pathDefinition,
      executor,
      referralCode
    );
  }

  /// @notice Internal logic for swapping between two sets of tokens with approvals
  /// @param inputs list of input token structs for the path being executed
  /// @param outputs list of output token structs for the path being executed
  /// @param valueOutMin minimum amount of value out the user will accept
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function _swapMultiApproval(
    inputTokenInfo[] memory inputs,
    outputTokenInfo[] memory outputs,
    uint256 valueOutMin,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    internal
    returns (uint256[] memory amountsOut)
  {
    // If input amount is still 0 then that means the maximum possible input is to be used
    uint256 expected_msg_value = 0;

    for (uint256 i = 0; i < inputs.length; i++) {
      if (inputs[i].tokenAddress == _ETH) {
        if (inputs[i].amountIn == 0) {
          inputs[i].amountIn = msg.value;
        }
        expected_msg_value = inputs[i].amountIn;
      } 
      else {
        if (inputs[i].amountIn == 0) {
          inputs[i].amountIn = IERC20(inputs[i].tokenAddress).balanceOf(msg.sender);
        }
        IERC20(inputs[i].tokenAddress).safeTransferFrom(
          msg.sender,
          inputs[i].receiver,
          inputs[i].amountIn
        );
      }
    }
    require(msg.value == expected_msg_value, "Wrong msg.value");

    return _swapMulti(
      inputs,
      outputs,
      valueOutMin,
      pathDefinition,
      executor,
      referralCode
    );
  }

  /// @notice Externally facing interface for swapping between two sets of tokens with Permit2
  /// @param permit2 All additional info for Permit2 transfers
  /// @param inputs list of input token structs for the path being executed
  /// @param outputs list of output token structs for the path being executed
  /// @param valueOutMin minimum amount of value out the user will accept
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function swapMultiPermit2(
    permit2Info memory permit2,
    inputTokenInfo[] memory inputs,
    outputTokenInfo[] memory outputs,
    uint256 valueOutMin,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    external
    payable
    returns (uint256[] memory amountsOut)
  {
    ISignatureTransfer.PermitBatchTransferFrom memory permit;
    ISignatureTransfer.SignatureTransferDetails[] memory transferDetails;
    {
      uint256 permit_length = msg.value > 0 ? inputs.length - 1 : inputs.length;

      permit = ISignatureTransfer.PermitBatchTransferFrom(
        new ISignatureTransfer.TokenPermissions[](permit_length),
        permit2.nonce,
        permit2.deadline
      );
      transferDetails = 
        new ISignatureTransfer.SignatureTransferDetails[](permit_length);
    }
    {
      uint256 expected_msg_value = 0;
      for (uint256 i = 0; i < inputs.length; i++) {

        if (inputs[i].tokenAddress == _ETH) {
          if (inputs[i].amountIn == 0) {
            inputs[i].amountIn = msg.value;
          }
          expected_msg_value = inputs[i].amountIn;
        }
        else {
          if (inputs[i].amountIn == 0) {
            inputs[i].amountIn = IERC20(inputs[i].tokenAddress).balanceOf(msg.sender);
          }
          uint256 permit_index = expected_msg_value == 0 ? i : i - 1;

          permit.permitted[permit_index].token = inputs[i].tokenAddress;
          permit.permitted[permit_index].amount = inputs[i].amountIn;

          transferDetails[permit_index].to = inputs[i].receiver;
          transferDetails[permit_index].requestedAmount = inputs[i].amountIn;
        }
      }
      require(msg.value == expected_msg_value, "Wrong msg.value");
    }
    ISignatureTransfer(permit2.contractAddress).permitTransferFrom(
      permit,
      transferDetails,
      msg.sender,
      permit2.signature
    );
    return _swapMulti(
      inputs,
      outputs,
      valueOutMin,
      pathDefinition,
      executor,
      referralCode
    );
  }

  /// @notice contains the main logic for swapping between two sets of tokens
  /// assumes that inputs have already been sent to the right location and msg.value
  /// is set correctly to be 0 for no native input and match native inpuit otherwise
  /// @param inputs list of input token structs for the path being executed
  /// @param outputs list of output token structs for the path being executed
  /// @param valueOutMin minimum amount of value out the user will accept
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  /// @param referralCode referral code to specify the source of the swap
  function _swapMulti(
    inputTokenInfo[] memory inputs,
    outputTokenInfo[] memory outputs,
    uint256 valueOutMin,
    bytes calldata pathDefinition,
    address executor,
    uint32 referralCode
  )
    internal
    returns (uint256[] memory amountsOut)
  {
    // Check for valid output specifications
    require(valueOutMin > 0, "Slippage limit too low");

    // Extract arrays of input amount values and tokens from the inputs struct list
    uint256[] memory amountsIn = new uint256[](inputs.length);
    address[] memory tokensIn = new address[](inputs.length);

    // Check input specification validity and transfer input tokens to executor
    {
      for (uint256 i = 0; i < inputs.length; i++) {

        amountsIn[i] = inputs[i].amountIn;
        tokensIn[i] = inputs[i].tokenAddress;

        for (uint256 j = 0; j < i; j++) {
          require(
            inputs[i].tokenAddress != inputs[j].tokenAddress,
            "Duplicate source tokens"
          );
        }
        for (uint256 j = 0; j < outputs.length; j++) {
          require(
            inputs[i].tokenAddress != outputs[j].tokenAddress,
            "Arbitrage not supported"
          );
        }
      }
    }
    // Check outputs for duplicates and record balances before swap
    uint256[] memory balancesBefore = new uint256[](outputs.length);
    for (uint256 i = 0; i < outputs.length; i++) {
      for (uint256 j = 0; j < i; j++) {
        require(
          outputs[i].tokenAddress != outputs[j].tokenAddress,
          "Duplicate destination tokens"
        );
      }
      balancesBefore[i] = _universalBalance(outputs[i].tokenAddress);
    }
    // Delegate the execution of the path to the specified Odos Executor
    IOdosExecutor(executor).executePath{value: msg.value}(pathDefinition, amountsIn, msg.sender);

    referralInfo memory thisReferralInfo;
    if (referralCode > REFERRAL_WITH_FEE_THRESHOLD) {
      thisReferralInfo = referralLookup[referralCode];
    }

    {
      uint256 valueOut;
      uint256 _swapMultiFee = swapMultiFee;
      amountsOut = new uint256[](outputs.length);

      for (uint256 i = 0; i < outputs.length; i++) {
        // Record the destination token balance before the path is executed
        amountsOut[i] = _universalBalance(outputs[i].tokenAddress) - balancesBefore[i];

        // Remove the swapMulti Fee (taken instead of positive slippage)
        amountsOut[i] = amountsOut[i] * (FEE_DENOM - _swapMultiFee) / FEE_DENOM;

        if (referralCode > REFERRAL_WITH_FEE_THRESHOLD) {
          _universalTransfer(
            outputs[i].tokenAddress,
            thisReferralInfo.beneficiary,
            amountsOut[i] * thisReferralInfo.referralFee * 8 / (FEE_DENOM * 10)
          );
          amountsOut[i] = amountsOut[i] * (FEE_DENOM - thisReferralInfo.referralFee) / FEE_DENOM;
        }
        _universalTransfer(
          outputs[i].tokenAddress,
          outputs[i].receiver,
          amountsOut[i]
        );
        // Add the amount out sent to the user to the total value of output
        valueOut += amountsOut[i] * outputs[i].relativeValue;
      }
      require(valueOut >= valueOutMin, "Slippage Limit Exceeded");
    }
    address[] memory tokensOut = new address[](outputs.length);
    for (uint256 i = 0; i < outputs.length; i++) {
        tokensOut[i] = outputs[i].tokenAddress;
    }
    emit SwapMulti(
      msg.sender,
      amountsIn,
      tokensIn,
      amountsOut,
      tokensOut,
      referralCode
    );
  }

  /// @notice Register a new referrer, optionally with an additional swap fee
  /// @param _referralCode the referral code to use for the new referral
  /// @param _referralFee the additional fee to add to each swap using this code
  /// @param _beneficiary the address to send the referral's share of fees to
  function registerReferralCode(
    uint32 _referralCode,
    uint64 _referralFee,
    address _beneficiary
  )
    external
  {
    // Do not allow for any overwriting of referral codes
    require(!referralLookup[_referralCode].registered, "Code in use");

    // Maximum additional fee a referral can set is 2%
    require(_referralFee <= FEE_DENOM / 50, "Fee too high");

    // Reserve the lower half of referral codes to be informative only
    if (_referralCode <= REFERRAL_WITH_FEE_THRESHOLD) {
      require(_referralFee == 0, "Invalid fee for code");
    } else {
      require(_referralFee > 0, "Invalid fee for code");

      // Make sure the beneficiary is not the null address if there is a fee
      require(_beneficiary != address(0), "Null beneficiary");
    }
    referralLookup[_referralCode].referralFee = _referralFee;
    referralLookup[_referralCode].beneficiary = _beneficiary;
    referralLookup[_referralCode].registered = true;
  }

  /// @notice Set the fee used for swapMulti
  /// @param _swapMultiFee the new fee for swapMulti
  function setSwapMultiFee(
    uint256 _swapMultiFee
  ) 
    external
    onlyOwner
  {
    // Maximum swapMultiFee that can be set is 0.5%
    require(_swapMultiFee <= FEE_DENOM / 200, "Fee too high");
    swapMultiFee = _swapMultiFee;
  }

  /// @notice Push new addresses to the cached address list for when storage is cheaper than calldata
  /// @param addresses list of addresses to be added to the cached address list
  function writeAddressList(
    address[] calldata addresses
  ) 
    external
    onlyOwner
  {
    for (uint256 i = 0; i < addresses.length; i++) {
      addressList.push(addresses[i]);
    }
  }

  /// @notice Allows the owner to transfer funds held by the router contract
  /// @param tokens List of token address to be transferred
  /// @param amounts List of amounts of each token to be transferred
  /// @param dest Address to which the funds should be sent
  function transferRouterFunds(
    address[] calldata tokens,
    uint256[] calldata amounts,
    address dest
  )
    external
    onlyOwner
  {
    require(tokens.length == amounts.length, "Invalid funds transfer");
    for (uint256 i = 0; i < tokens.length; i++) {
      _universalTransfer(
        tokens[i], 
        dest, 
        amounts[i] == 0 ? _universalBalance(tokens[i]) : amounts[i]
      );
    }
  }
  /// @notice Directly swap funds held in router 
  /// @param inputs list of input token structs for the path being executed
  /// @param outputs list of output token structs for the path being executed
  /// @param valueOutMin minimum amount of value out the user will accept
  /// @param pathDefinition Encoded path definition for executor
  /// @param executor Address of contract that will execute the path
  function swapRouterFunds(
    inputTokenInfo[] memory inputs,
    outputTokenInfo[] memory outputs,
    uint256 valueOutMin,
    bytes calldata pathDefinition,
    address executor
  )
    external
    onlyOwner
    returns (uint256[] memory amountsOut)
  {
    uint256[] memory amountsIn = new uint256[](inputs.length);
    address[] memory tokensIn = new address[](inputs.length);

    for (uint256 i = 0; i < inputs.length; i++) {
      tokensIn[i] = inputs[i].tokenAddress;

      amountsIn[i] = inputs[i].amountIn == 0 ? 
        _universalBalance(tokensIn[i]) : inputs[i].amountIn;

      _universalTransfer(
        tokensIn[i],
        inputs[i].receiver,
        amountsIn[i]
      );
    }
    // Check outputs for duplicates and record balances before swap
    uint256[] memory balancesBefore = new uint256[](outputs.length);
    address[] memory tokensOut = new address[](outputs.length);
    for (uint256 i = 0; i < outputs.length; i++) {
      tokensOut[i] = outputs[i].tokenAddress;
      balancesBefore[i] = _universalBalance(tokensOut[i]);
    }
    // Delegate the execution of the path to the specified Odos Executor
    IOdosExecutor(executor).executePath{value: 0}(pathDefinition, amountsIn, msg.sender);

    uint256 valueOut;
    amountsOut = new uint256[](outputs.length);
    for (uint256 i = 0; i < outputs.length; i++) {

      // Record the destination token balance before the path is executed
      amountsOut[i] = _universalBalance(tokensOut[i]) - balancesBefore[i];

      _universalTransfer(
        outputs[i].tokenAddress,
        outputs[i].receiver,
        amountsOut[i]
      );
      // Add the amount out sent to the user to the total value of output
      valueOut += amountsOut[i] * outputs[i].relativeValue;
    }
    require(valueOut >= valueOutMin, "Slippage Limit Exceeded");

    emit SwapMulti(
      msg.sender,
      amountsIn,
      tokensIn,
      amountsOut,
      tokensOut,
      0
    );
  }
  /// @notice helper function to get balance of ERC20 or native coin for this contract
  /// @param token address of the token to check, null for native coin
  /// @return balance of specified coin or token
  function _universalBalance(address token) private view returns(uint256) {
    if (token == _ETH) {
      return address(this).balance;
    } else {
      return IERC20(token).balanceOf(address(this));
    }
  }
  /// @notice helper function to transfer ERC20 or native coin
  /// @param token address of the token being transferred, null for native coin
  /// @param to address to transfer to
  /// @param amount to transfer
  function _universalTransfer(address token, address to, uint256 amount) private {
    if (token == _ETH) {
      (bool success,) = payable(to).call{value: amount}("");
      require(success, "ETH transfer failed");
    } else {
      IERC20(token).safeTransfer(to, amount);
    }
  }
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.8.0;
pragma abicoder v2;
import {SafeMath} from "@openzeppelin/contracts/utils/math/SafeMath.sol";
import {Math} from "@openzeppelin/contracts/utils/math/Math.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {UniswapV2Pair} from "../helpers/uni-v2/UniswapV2Pair.sol";
import {IUniswapV2Factory} from "../helpers/uni-v2/interfaces/IUniswapV2Factory.sol";
import {UQ112x112} from "../helpers/uni-v2/libraries/UQ112x112.sol";
import {RegistryAPI} from "../helpers/yearn/BaseWrapper.sol";
import {YapeWrapper} from "./YapeWrapper.sol";
import {IYapePair} from "../interfaces/IYapePair.sol";
import {IYapeFactory} from "../interfaces/IYapeFactory.sol";
contract YapePair is UniswapV2Pair, YapeWrapper {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;
    using UQ112x112 for uint224;
    mapping(address => uint256) public farming;
    uint256 private _minFarming;
    uint256 private _maxFarming;
    address private _registry;
    uint256 private constant DENOMINATOR = 10000;
    event YearnDeposit(address token, uint256 amount);
    event YearnWithdraw(address token, uint256 amount, uint256 yield);
    modifier onlyOperator() {
        require(msg.sender == IYapeFactory(factory).operator());
        _;
    }
    modifier onlyReserved(address token) {
        require(
            token == token0 || token == token1,
            "Yapeswap: NOT A RESERVED TOKEN"
        );
        _;
    }
    modifier keepBalance(address token) {
        uint256 prevBal = _balanceOf(token);
        _;
        require(_balanceOf(token) == prevBal, "Yapeswap: BALANCE CHANGED");
    }
    function mint(address to) public override returns (uint256 liquidity) {
        liquidity = super.mint(to);
        _rebalance(token0, 0, false);
        _rebalance(token1, 0, false);
    }
    function updateRegistry() public {
        _registry = IYapeFactory(factory).registry();
    }
    function setFarmingRatio(uint256 min, uint256 max) external onlyOperator {
        require(max <= DENOMINATOR);
        require(min <= max);
        _minFarming = min;
        _maxFarming = max;
    }
    /**
     * @param token use token0 or token1
     * @param amount use type(uint256).max (when you want to migrate all)
     * @param maxMigrationLoss use 0 for the default value
     */
    function migrate(
        address token,
        uint256 amount,
        uint256 maxMigrationLoss
    ) external onlyOperator onlyReserved(token) returns (uint256) {
        return _migrate(token, address(this), amount, maxMigrationLoss);
    }
    function rebalance(address token) external onlyReserved(token) {
        _rebalance(token, 0, true);
    }
    function registry() public view override returns (RegistryAPI) {
        return RegistryAPI(_registry);
    }
    function farmingRatio() public view returns (uint256 min, uint256 max) {
        return (_minFarming, _maxFarming);
    }
    function name() public view override returns (string memory) {
        return "Yape LP";
    }
    function symbol() public view override returns (string memory) {
        return "YLP";
    }
    function _balanceOf(address token)
        internal
        view
        override
        returns (uint256)
    {
        return IERC20(token).balanceOf(address(this)).add(farming[token]);
    }
    function _safeTransfer(
        address token,
        address to,
        uint256 value
    ) internal override {
        _rebalance(token, value, false);
        (bool success, bytes memory data) = token.call(
            abi.encodeWithSelector(SELECTOR, to, value)
        );
        require(
            success && (data.length == 0 || abi.decode(data, (bool))),
            "UniswapV2: TRANSFER_FAILED"
        );
    }
    function _rebalance(
        address token,
        uint256 amountOut,
        bool force
    ) internal {
        uint256 newBal = _balanceOf(token).sub(amountOut);
        uint256 minFarming = newBal.mul(_minFarming).div(DENOMINATOR);
        uint256 maxFarming = newBal.mul(_maxFarming).div(DENOMINATOR);
        uint256 currentFarming = farming[token];
        uint256 avg = Math.average(minFarming, maxFarming);
        if (currentFarming > maxFarming || (force && currentFarming > avg)) {
            // should withdraw from Yearn
            _fromYearn(token, currentFarming - avg);
        } else if (
            minFarming > currentFarming || (force && avg > currentFarming)
        ) {
            // should deposit to Yearn
            _toYearn(token, avg - currentFarming);
        }
    }
    function _toYearn(address token, uint256 amount)
        internal
        keepBalance(token)
    {
        uint256 deposited = _deposit(
            token,
            address(this),
            address(this),
            amount,
            false
        );
        farming[token] = farming[token].add(deposited);
        emit YearnDeposit(token, amount);
    }
    function _fromYearn(address token, uint256 amount)
        internal
        keepBalance(token)
    {
        uint256 yearnBal = totalVaultBalance(token, address(this));
        uint256 farmingAmount = farming[token];
        uint256 yield;
        if (yearnBal > farmingAmount) {
            yield = yearnBal - farmingAmount;
        } else {
            // rare case
            yield = 0;
        }
        uint256 withdrawn = _withdraw(
            token,
            address(this),
            address(this),
            amount.add(yield),
            true
        );
        uint256 netYield;
        if (withdrawn > amount) {
            netYield = withdrawn - amount;
        } else {
            netYield = 0;
        }
        farming[token] = farmingAmount.sub(withdrawn - netYield);
        // Send fee
        address feeTo = IUniswapV2Factory(factory).feeTo();
        if (netYield > 0) {
            IERC20(token).safeTransfer(feeTo, netYield);
        }
        emit YearnWithdraw(token, withdrawn, netYield);
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
import "./interfaces/IUniswapV2Pair.sol";
import "./UniswapV2ERC20.sol";
import "./libraries/Math.sol";
import "./libraries/UQ112x112.sol";
import "./interfaces/IERC20.sol";
import "./interfaces/IUniswapV2Factory.sol";
import "./interfaces/IUniswapV2Callee.sol";
contract UniswapV2Pair is UniswapV2ERC20 {
    using SafeMath for uint256;
    using UQ112x112 for uint224;
    uint256 public constant MINIMUM_LIQUIDITY = 10**3;
    bytes4 internal constant SELECTOR =
        bytes4(keccak256(bytes("transfer(address,uint256)")));
    address public factory;
    address public token0;
    address public token1;
    uint112 internal reserve0; // uses single storage slot, accessible via getReserves
    uint112 internal reserve1; // uses single storage slot, accessible via getReserves
    uint32 internal blockTimestampLast; // uses single storage slot, accessible via getReserves
    uint256 public price0CumulativeLast;
    uint256 public price1CumulativeLast;
    uint256 public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event
    uint256 internal unlocked = 1;
    modifier lock() {
        require(unlocked == 1, "UniswapV2: LOCKED");
        unlocked = 0;
        _;
        unlocked = 1;
    }
    event Mint(address indexed sender, uint256 amount0, uint256 amount1);
    event Burn(
        address indexed sender,
        uint256 amount0,
        uint256 amount1,
        address indexed to
    );
    event Swap(
        address indexed sender,
        uint256 amount0In,
        uint256 amount1In,
        uint256 amount0Out,
        uint256 amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);
    constructor() {
        factory = msg.sender;
    }
    // called once by the factory at time of deployment
    function initialize(address _token0, address _token1) public virtual {
        require(msg.sender == factory, "UniswapV2: FORBIDDEN"); // sufficient check
        token0 = _token0;
        token1 = _token1;
    }
    // this low-level function should be called from a contract which performs important safety checks
    function mint(address to) public virtual lock returns (uint256 liquidity) {
        (uint112 _reserve0, uint112 _reserve1, ) = getReserves(); // gas savings
        uint256 balance0 = _balanceOf(token0);
        uint256 balance1 = _balanceOf(token1);
        uint256 amount0 = balance0.sub(_reserve0);
        uint256 amount1 = balance1.sub(_reserve1);
        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint256 _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 = uint256(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)
        public
        virtual
        lock
        returns (uint256 amount0, uint256 amount1)
    {
        (uint112 _reserve0, uint112 _reserve1, ) = getReserves(); // gas savings
        address _token0 = token0; // gas savings
        address _token1 = token1; // gas savings
        uint256 balance0 = _balanceOf(_token0);
        uint256 balance1 = _balanceOf(_token1);
        uint256 liquidity = balanceOf[address(this)];
        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint256 _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 = _balanceOf(_token0);
        balance1 = _balanceOf(_token1);
        _update(balance0, balance1, _reserve0, _reserve1);
        if (feeOn) kLast = uint256(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(
        uint256 amount0Out,
        uint256 amount1Out,
        address to,
        bytes calldata data
    ) public virtual 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"
        );
        uint256 balance0;
        uint256 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 = _balanceOf(_token0);
            balance1 = _balanceOf(_token1);
        }
        uint256 amount0In = balance0 > _reserve0 - amount0Out
            ? balance0 - (_reserve0 - amount0Out)
            : 0;
        uint256 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
            uint256 balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
            uint256 balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
            require(
                balance0Adjusted.mul(balance1Adjusted) >=
                    uint256(_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) public virtual lock {
        address _token0 = token0; // gas savings
        address _token1 = token1; // gas savings
        _safeTransfer(_token0, to, _balanceOf(_token0).sub(reserve0));
        _safeTransfer(_token1, to, _balanceOf(_token1).sub(reserve1));
    }
    // force reserves to match balances
    function sync() public virtual lock {
        _update(_balanceOf(token0), _balanceOf(token1), reserve0, reserve1);
    }
    function getReserves()
        public
        view
        returns (
            uint112 _reserve0,
            uint112 _reserve1,
            uint32 _blockTimestampLast
        )
    {
        _reserve0 = reserve0;
        _reserve1 = reserve1;
        _blockTimestampLast = blockTimestampLast;
    }
    function _safeTransfer(
        address token,
        address to,
        uint256 value
    ) internal virtual {
        (bool success, bytes memory data) = token.call(
            abi.encodeWithSelector(SELECTOR, to, value)
        );
        require(
            success && (data.length == 0 || abi.decode(data, (bool))),
            "UniswapV2: TRANSFER_FAILED"
        );
    }
    // update reserves and, on the first call per block, price accumulators
    function _update(
        uint256 balance0,
        uint256 balance1,
        uint112 _reserve0,
        uint112 _reserve1
    ) internal virtual {
        require(
            balance0 <= ~uint112(0) && balance1 <= ~uint112(0),
            "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 +=
                uint256(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) *
                timeElapsed;
            price1CumulativeLast +=
                uint256(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)
        internal
        virtual
        returns (bool feeOn)
    {
        address feeTo = IUniswapV2Factory(factory).feeTo();
        feeOn = feeTo != address(0);
        uint256 _kLast = kLast; // gas savings
        if (feeOn) {
            if (_kLast != 0) {
                uint256 rootK = Math.sqrt(uint256(_reserve0).mul(_reserve1));
                uint256 rootKLast = Math.sqrt(_kLast);
                if (rootK > rootKLast) {
                    uint256 numerator = totalSupply.mul(rootK.sub(rootKLast));
                    uint256 denominator = rootK.mul(5).add(rootKLast);
                    uint256 liquidity = numerator / denominator;
                    if (liquidity > 0) _mint(feeTo, liquidity);
                }
            }
        } else if (_kLast != 0) {
            kLast = 0;
        }
    }
    function _balanceOf(address token) internal view virtual returns (uint256) {
        return IERC20(token).balanceOf(address(this));
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
interface IUniswapV2Pair {
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 value);
    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint256);
    function balanceOf(address owner) external view returns (uint256);
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);
    function approve(address spender, uint256 value) external returns (bool);
    function transfer(address to, uint256 value) external returns (bool);
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);
    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint256);
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
    event Mint(address indexed sender, uint256 amount0, uint256 amount1);
    event Burn(
        address indexed sender,
        uint256 amount0,
        uint256 amount1,
        address indexed to
    );
    event Swap(
        address indexed sender,
        uint256 amount0In,
        uint256 amount1In,
        uint256 amount0Out,
        uint256 amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);
    function MINIMUM_LIQUIDITY() external pure returns (uint256);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves()
        external
        view
        returns (
            uint112 reserve0,
            uint112 reserve1,
            uint32 blockTimestampLast
        );
    function price0CumulativeLast() external view returns (uint256);
    function price1CumulativeLast() external view returns (uint256);
    function kLast() external view returns (uint256);
    function mint(address to) external returns (uint256 liquidity);
    function burn(address to)
        external
        returns (uint256 amount0, uint256 amount1);
    function swap(
        uint256 amount0Out,
        uint256 amount1Out,
        address to,
        bytes calldata data
    ) external;
    function skim(address to) external;
    function sync() external;
    function initialize(address, address) external;
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
import "./interfaces/IUniswapV2ERC20.sol";
import "./libraries/SafeMath.sol";
contract UniswapV2ERC20 {
    using SafeMath for uint256;
    uint8 public constant decimals = 18;
    uint256 public totalSupply;
    mapping(address => uint256) public balanceOf;
    mapping(address => mapping(address => uint256)) 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 => uint256) public nonces;
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 value);
    constructor() {
        uint256 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, uint256 value) internal {
        totalSupply = totalSupply.add(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(address(0), to, value);
    }
    function _burn(address from, uint256 value) internal {
        balanceOf[from] = balanceOf[from].sub(value);
        totalSupply = totalSupply.sub(value);
        emit Transfer(from, address(0), value);
    }
    function _approve(
        address owner,
        address spender,
        uint256 value
    ) private {
        allowance[owner][spender] = value;
        emit Approval(owner, spender, value);
    }
    function _transfer(
        address from,
        address to,
        uint256 value
    ) private {
        balanceOf[from] = balanceOf[from].sub(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(from, to, value);
    }
    function approve(address spender, uint256 value) external returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }
    function transfer(address to, uint256 value) external returns (bool) {
        _transfer(msg.sender, to, value);
        return true;
    }
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool) {
        if (allowance[from][msg.sender] != ~uint256(0)) {
            allowance[from][msg.sender] = allowance[from][msg.sender].sub(
                value
            );
        }
        _transfer(from, to, value);
        return true;
    }
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 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);
    }
    function name() public view virtual returns (string memory) {
        return "Uniswap V2";
    }
    function symbol() public view virtual returns (string memory) {
        return "UNI-V2";
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
interface IUniswapV2ERC20 {
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 value);
    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint256);
    function balanceOf(address owner) external view returns (uint256);
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);
    function approve(address spender, uint256 value) external returns (bool);
    function transfer(address to, uint256 value) external returns (bool);
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);
    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint256);
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
library SafeMath {
    function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x + y) >= x, "ds-math-add-overflow");
    }
    function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require((z = x - y) <= x, "ds-math-sub-underflow");
    }
    function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
        require(y == 0 || (z = x * y) / y == x, "ds-math-mul-overflow");
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
// a library for performing various math operations
library Math {
    function min(uint256 x, uint256 y) internal pure returns (uint256 z) {
        z = x < y ? x : y;
    }
    // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
    function sqrt(uint256 y) internal pure returns (uint256 z) {
        if (y > 3) {
            z = y;
            uint256 x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
// 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);
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
interface IERC20 {
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 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 (uint256);
    function balanceOf(address owner) external view returns (uint256);
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);
    function approve(address spender, uint256 value) external returns (bool);
    function transfer(address to, uint256 value) external returns (bool);
    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
interface IUniswapV2Factory {
    event PairCreated(
        address indexed token0,
        address indexed token1,
        address pair,
        uint256
    );
    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);
    function getPair(address tokenA, address tokenB)
        external
        view
        returns (address pair);
    function allPairs(uint256) external view returns (address pair);
    function allPairsLength() external view returns (uint256);
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
interface IUniswapV2Callee {
    function uniswapV2Call(
        address sender,
        uint256 amount0,
        uint256 amount1,
        bytes calldata data
    ) external;
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
pragma abicoder v2;
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {Math} from "@openzeppelin/contracts/utils/math/Math.sol";
import {SafeMath} from "@openzeppelin/contracts/utils/math/SafeMath.sol";
import {VaultAPI} from "./BaseStrategy.sol";
interface RegistryAPI {
    function governance() external view returns (address);
    function latestVault(address token) external view returns (address);
    function numVaults(address token) external view returns (uint256);
    function vaults(address token, uint256 deploymentId)
        external
        view
        returns (address);
}
/**
 * @title Yearn Base Wrapper
 * @author yearn.finance
 * @notice
 *  BaseWrapper implements all of the required functionality to interoperate
 *  closely with the Vault contract. This contract should be inherited and the
 *  abstract methods implemented to adapt the Wrapper.
 *  A good starting point to build a wrapper is https://github.com/yearn/brownie-wrapper-mix
 *
 */
abstract contract BaseWrapper {
    using Math for uint256;
    using SafeMath for uint256;
    IERC20 public token;
    // Reduce number of external calls (SLOADs stay the same)
    VaultAPI[] private _cachedVaults;
    RegistryAPI public registry;
    // ERC20 Unlimited Approvals (short-circuits VaultAPI.transferFrom)
    uint256 constant UNLIMITED_APPROVAL = type(uint256).max;
    // Sentinal values used to save gas on deposit/withdraw/migrate
    // NOTE: DEPOSIT_EVERYTHING == WITHDRAW_EVERYTHING == MIGRATE_EVERYTHING
    uint256 constant DEPOSIT_EVERYTHING = type(uint256).max;
    uint256 constant WITHDRAW_EVERYTHING = type(uint256).max;
    uint256 constant MIGRATE_EVERYTHING = type(uint256).max;
    // VaultsAPI.depositLimit is unlimited
    uint256 constant UNCAPPED_DEPOSITS = type(uint256).max;
    constructor(address _token, address _registry) {
        // Recommended to use a token with a `Registry.latestVault(_token) != address(0)`
        token = IERC20(_token);
        // Recommended to use `v2.registry.ychad.eth`
        registry = RegistryAPI(_registry);
    }
    /**
     * @notice
     *  Used to update the yearn registry.
     * @param _registry The new _registry address.
     */
    function setRegistry(address _registry) external {
        require(msg.sender == registry.governance());
        // In case you want to override the registry instead of re-deploying
        registry = RegistryAPI(_registry);
        // Make sure there's no change in governance
        // NOTE: Also avoid bricking the wrapper from setting a bad registry
        require(msg.sender == registry.governance());
    }
    /**
     * @notice
     *  Used to get the most revent vault for the token using the registry.
     * @return An instance of a VaultAPI
     */
    function bestVault() public view virtual returns (VaultAPI) {
        return VaultAPI(registry.latestVault(address(token)));
    }
    /**
     * @notice
     *  Used to get all vaults from the registery for the token
     * @return An array containing instances of VaultAPI
     */
    function allVaults() public view virtual returns (VaultAPI[] memory) {
        uint256 cache_length = _cachedVaults.length;
        uint256 num_vaults = registry.numVaults(address(token));
        // Use cached
        if (cache_length == num_vaults) {
            return _cachedVaults;
        }
        VaultAPI[] memory vaults = new VaultAPI[](num_vaults);
        for (uint256 vault_id = 0; vault_id < cache_length; vault_id++) {
            vaults[vault_id] = _cachedVaults[vault_id];
        }
        for (
            uint256 vault_id = cache_length;
            vault_id < num_vaults;
            vault_id++
        ) {
            vaults[vault_id] = VaultAPI(
                registry.vaults(address(token), vault_id)
            );
        }
        return vaults;
    }
    function _updateVaultCache(VaultAPI[] memory vaults) internal {
        // NOTE: even though `registry` is update-able by Yearn, the intended behavior
        //       is that any future upgrades to the registry will replay the version
        //       history so that this cached value does not get out of date.
        if (vaults.length > _cachedVaults.length) {
            _cachedVaults = vaults;
        }
    }
    /**
     * @notice
     *  Used to get the balance of an account accross all the vaults for a token.
     *  @dev will be used to get the wrapper balance using totalVaultBalance(address(this)).
     *  @param account The address of the account.
     *  @return balance of token for the account accross all the vaults.
     */
    function totalVaultBalance(address account)
        public
        view
        returns (uint256 balance)
    {
        VaultAPI[] memory vaults = allVaults();
        for (uint256 id = 0; id < vaults.length; id++) {
            balance = balance.add(
                vaults[id]
                .balanceOf(account)
                .mul(vaults[id].pricePerShare())
                .div(10**uint256(vaults[id].decimals()))
            );
        }
    }
    /**
     * @notice
     *  Used to get the TVL on the underlying vaults.
     *  @return assets the sum of all the assets managed by the underlying vaults.
     */
    function totalAssets() public view returns (uint256 assets) {
        VaultAPI[] memory vaults = allVaults();
        for (uint256 id = 0; id < vaults.length; id++) {
            assets = assets.add(vaults[id].totalAssets());
        }
    }
    function _deposit(
        address depositor,
        address receiver,
        uint256 amount, // if `MAX_UINT256`, just deposit everything
        bool pullFunds // If true, funds need to be pulled from `depositor` via `transferFrom`
    ) internal returns (uint256 deposited) {
        VaultAPI _bestVault = bestVault();
        if (pullFunds) {
            if (amount != DEPOSIT_EVERYTHING) {
                SafeERC20.safeTransferFrom(
                    token,
                    depositor,
                    address(this),
                    amount
                );
            } else {
                SafeERC20.safeTransferFrom(
                    token,
                    depositor,
                    address(this),
                    token.balanceOf(depositor)
                );
            }
        }
        if (token.allowance(address(this), address(_bestVault)) < amount) {
            SafeERC20.safeApprove(token, address(_bestVault), 0); // Avoid issues with some tokens requiring 0
            SafeERC20.safeApprove(
                token,
                address(_bestVault),
                UNLIMITED_APPROVAL
            ); // Vaults are trusted
        }
        // Depositing returns number of shares deposited
        // NOTE: Shortcut here is assuming the number of tokens deposited is equal to the
        //       number of shares credited, which helps avoid an occasional multiplication
        //       overflow if trying to adjust the number of shares by the share price.
        uint256 beforeBal = token.balanceOf(address(this));
        if (receiver != address(this)) {
            _bestVault.deposit(amount, receiver);
        } else if (amount != DEPOSIT_EVERYTHING) {
            _bestVault.deposit(amount);
        } else {
            _bestVault.deposit();
        }
        uint256 afterBal = token.balanceOf(address(this));
        deposited = beforeBal.sub(afterBal);
        // `receiver` now has shares of `_bestVault` as balance, converted to `token` here
        // Issue a refund if not everything was deposited
        if (depositor != address(this) && afterBal > 0)
            SafeERC20.safeTransfer(token, depositor, afterBal);
    }
    function _withdraw(
        address sender,
        address receiver,
        uint256 amount, // if `MAX_UINT256`, just withdraw everything
        bool withdrawFromBest // If true, also withdraw from `_bestVault`
    ) internal returns (uint256 withdrawn) {
        VaultAPI _bestVault = bestVault();
        VaultAPI[] memory vaults = allVaults();
        _updateVaultCache(vaults);
        // NOTE: This loop will attempt to withdraw from each Vault in `allVaults` that `sender`
        //       is deposited in, up to `amount` tokens. The withdraw action can be expensive,
        //       so it if there is a denial of service issue in withdrawing, the downstream usage
        //       of this wrapper contract must give an alternative method of withdrawing using
        //       this function so that `amount` is less than the full amount requested to withdraw
        //       (e.g. "piece-wise withdrawals"), leading to less loop iterations such that the
        //       DoS issue is mitigated (at a tradeoff of requiring more txns from the end user).
        for (uint256 id = 0; id < vaults.length; id++) {
            if (!withdrawFromBest && vaults[id] == _bestVault) {
                continue; // Don't withdraw from the best
            }
            // Start with the total shares that `sender` has
            uint256 availableShares = vaults[id].balanceOf(sender);
            // Restrict by the allowance that `sender` has to this contract
            // NOTE: No need for allowance check if `sender` is this contract
            if (sender != address(this)) {
                availableShares = Math.min(
                    availableShares,
                    vaults[id].allowance(sender, address(this))
                );
            }
            // Limit by maximum withdrawal size from each vault
            availableShares = Math.min(
                availableShares,
                vaults[id].maxAvailableShares()
            );
            if (availableShares > 0) {
                // Intermediate step to move shares to this contract before withdrawing
                // NOTE: No need for share transfer if this contract is `sender`
                if (sender != address(this))
                    vaults[id].transferFrom(
                        sender,
                        address(this),
                        availableShares
                    );
                if (amount != WITHDRAW_EVERYTHING) {
                    // Compute amount to withdraw fully to satisfy the request
                    uint256 estimatedShares = amount
                    .sub(withdrawn) // NOTE: Changes every iteration
                    .mul(10**uint256(vaults[id].decimals()))
                    .div(vaults[id].pricePerShare()); // NOTE: Every Vault is different
                    // Limit amount to withdraw to the maximum made available to this contract
                    // NOTE: Avoid corner case where `estimatedShares` isn't precise enough
                    // NOTE: If `0 < estimatedShares < 1` but `availableShares > 1`, this will withdraw more than necessary
                    if (
                        estimatedShares > 0 && estimatedShares < availableShares
                    ) {
                        withdrawn = withdrawn.add(
                            vaults[id].withdraw(estimatedShares)
                        );
                    } else {
                        withdrawn = withdrawn.add(
                            vaults[id].withdraw(availableShares)
                        );
                    }
                } else {
                    withdrawn = withdrawn.add(vaults[id].withdraw());
                }
                // Check if we have fully satisfied the request
                // NOTE: use `amount = WITHDRAW_EVERYTHING` for withdrawing everything
                if (amount <= withdrawn) break; // withdrawn as much as we needed
            }
        }
        // If we have extra, deposit back into `_bestVault` for `sender`
        // NOTE: Invariant is `withdrawn <= amount`
        if (
            withdrawn > amount &&
            withdrawn.sub(amount) >
            _bestVault.pricePerShare().div(10**_bestVault.decimals())
        ) {
            // Don't forget to approve the deposit
            if (
                token.allowance(address(this), address(_bestVault)) <
                withdrawn.sub(amount)
            ) {
                SafeERC20.safeApprove(
                    token,
                    address(_bestVault),
                    UNLIMITED_APPROVAL
                ); // Vaults are trusted
            }
            _bestVault.deposit(withdrawn.sub(amount), sender);
            withdrawn = amount;
        }
        // `receiver` now has `withdrawn` tokens as balance
        if (receiver != address(this))
            SafeERC20.safeTransfer(token, receiver, withdrawn);
    }
    function _migrate(address account) internal returns (uint256) {
        return _migrate(account, MIGRATE_EVERYTHING);
    }
    function _migrate(address account, uint256 amount)
        internal
        returns (uint256)
    {
        // NOTE: In practice, it was discovered that <50 was the maximum we've see for this variance
        return _migrate(account, amount, 0);
    }
    function _migrate(
        address account,
        uint256 amount,
        uint256 maxMigrationLoss
    ) internal returns (uint256 migrated) {
        VaultAPI _bestVault = bestVault();
        // NOTE: Only override if we aren't migrating everything
        uint256 _depositLimit = _bestVault.depositLimit();
        uint256 _totalAssets = _bestVault.totalAssets();
        if (_depositLimit <= _totalAssets) return 0; // Nothing to migrate (not a failure)
        uint256 _amount = amount;
        if (
            _depositLimit < UNCAPPED_DEPOSITS && _amount < WITHDRAW_EVERYTHING
        ) {
            // Can only deposit up to this amount
            uint256 _depositLeft = _depositLimit.sub(_totalAssets);
            if (_amount > _depositLeft) _amount = _depositLeft;
        }
        if (_amount > 0) {
            // NOTE: `false` = don't withdraw from `_bestVault`
            uint256 withdrawn = _withdraw(
                account,
                address(this),
                _amount,
                false
            );
            if (withdrawn == 0) return 0; // Nothing to migrate (not a failure)
            // NOTE: `false` = don't do `transferFrom` because it's already local
            migrated = _deposit(address(this), account, withdrawn, false);
            // NOTE: Due to the precision loss of certain calculations, there is a small inefficency
            //       on how migrations are calculated, and this could lead to a DoS issue. Hence, this
            //       value is made to be configurable to allow the user to specify how much is acceptable
            require(withdrawn.sub(migrated) <= maxMigrationLoss);
        } // else: nothing to migrate! (not a failure)
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
pragma abicoder v2;
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {SafeMath} from "@openzeppelin/contracts/utils/math/SafeMath.sol";
struct StrategyParams {
    uint256 performanceFee;
    uint256 activation;
    uint256 debtRatio;
    uint256 minDebtPerHarvest;
    uint256 maxDebtPerHarvest;
    uint256 lastReport;
    uint256 totalDebt;
    uint256 totalGain;
    uint256 totalLoss;
    bool enforceChangeLimit;
    uint256 profitLimitRatio;
    uint256 lossLimitRatio;
    address customCheck;
}
interface VaultAPI is IERC20 {
    function name() external view returns (string calldata);
    function symbol() external view returns (string calldata);
    function decimals() external view returns (uint256);
    function apiVersion() external pure returns (string memory);
    function permit(
        address owner,
        address spender,
        uint256 amount,
        uint256 expiry,
        bytes calldata signature
    ) external returns (bool);
    // NOTE: Vyper produces multiple signatures for a given function with "default" args
    function deposit() external returns (uint256);
    function deposit(uint256 amount) external returns (uint256);
    function deposit(uint256 amount, address recipient)
        external
        returns (uint256);
    // NOTE: Vyper produces multiple signatures for a given function with "default" args
    function withdraw() external returns (uint256);
    function withdraw(uint256 maxShares) external returns (uint256);
    function withdraw(uint256 maxShares, address recipient)
        external
        returns (uint256);
    function token() external view returns (address);
    function strategies(address _strategy)
        external
        view
        returns (StrategyParams memory);
    function pricePerShare() external view returns (uint256);
    function totalAssets() external view returns (uint256);
    function depositLimit() external view returns (uint256);
    function maxAvailableShares() external view returns (uint256);
    /**
     * View how much the Vault would increase this Strategy's borrow limit,
     * based on its present performance (since its last report). Can be used to
     * determine expectedReturn in your Strategy.
     */
    function creditAvailable() external view returns (uint256);
    /**
     * View how much the Vault would like to pull back from the Strategy,
     * based on its present performance (since its last report). Can be used to
     * determine expectedReturn in your Strategy.
     */
    function debtOutstanding() external view returns (uint256);
    /**
     * View how much the Vault expect this Strategy to return at the current
     * block, based on its present performance (since its last report). Can be
     * used to determine expectedReturn in your Strategy.
     */
    function expectedReturn() external view returns (uint256);
    /**
     * This is the main contact point where the Strategy interacts with the
     * Vault. It is critical that this call is handled as intended by the
     * Strategy. Therefore, this function will be called by BaseStrategy to
     * make sure the integration is correct.
     */
    function report(
        uint256 _gain,
        uint256 _loss,
        uint256 _debtPayment
    ) external returns (uint256);
    /**
     * This function should only be used in the scenario where the Strategy is
     * being retired but no migration of the positions are possible, or in the
     * extreme scenario that the Strategy needs to be put into "Emergency Exit"
     * mode in order for it to exit as quickly as possible. The latter scenario
     * could be for any reason that is considered "critical" that the Strategy
     * exits its position as fast as possible, such as a sudden change in
     * market conditions leading to losses, or an imminent failure in an
     * external dependency.
     */
    function revokeStrategy() external;
    /**
     * View the governance address of the Vault to assert privileged functions
     * can only be called by governance. The Strategy serves the Vault, so it
     * is subject to governance defined by the Vault.
     */
    function governance() external view returns (address);
    /**
     * View the management address of the Vault to assert privileged functions
     * can only be called by management. The Strategy serves the Vault, so it
     * is subject to management defined by the Vault.
     */
    function management() external view returns (address);
    /**
     * View the guardian address of the Vault to assert privileged functions
     * can only be called by guardian. The Strategy serves the Vault, so it
     * is subject to guardian defined by the Vault.
     */
    function guardian() external view returns (address);
}
/**
 * This interface is here for the keeper bot to use.
 */
interface StrategyAPI {
    function name() external view returns (string memory);
    function vault() external view returns (address);
    function want() external view returns (address);
    function apiVersion() external pure returns (string memory);
    function keeper() external view returns (address);
    function isActive() external view returns (bool);
    function delegatedAssets() external view returns (uint256);
    function estimatedTotalAssets() external view returns (uint256);
    function tendTrigger(uint256 callCost) external view returns (bool);
    function tend() external;
    function harvestTrigger(uint256 callCost) external view returns (bool);
    function harvest() external;
    event Harvested(
        uint256 profit,
        uint256 loss,
        uint256 debtPayment,
        uint256 debtOutstanding
    );
}
/**
 * @title Yearn Base Strategy
 * @author yearn.finance
 * @notice
 *  BaseStrategy implements all of the required functionality to interoperate
 *  closely with the Vault contract. This contract should be inherited and the
 *  abstract methods implemented to adapt the Strategy to the particular needs
 *  it has to create a return.
 *
 *  Of special interest is the relationship between `harvest()` and
 *  `vault.report()'. `harvest()` may be called simply because enough time has
 *  elapsed since the last report, and not because any funds need to be moved
 *  or positions adjusted. This is critical so that the Vault may maintain an
 *  accurate picture of the Strategy's performance. See  `vault.report()`,
 *  `harvest()`, and `harvestTrigger()` for further details.
 */
abstract contract BaseStrategy {
    using SafeMath for uint256;
    string public metadataURI;
    /**
     * @notice
     *  Used to track which version of `StrategyAPI` this Strategy
     *  implements.
     * @dev The Strategy's version must match the Vault's `API_VERSION`.
     * @return A string which holds the current API version of this contract.
     */
    function apiVersion() public pure returns (string memory) {
        return "0.4.2";
    }
    /**
     * @notice This Strategy's name.
     * @dev
     *  You can use this field to manage the "version" of this Strategy, e.g.
     *  `StrategySomethingOrOtherV1`. However, "API Version" is managed by
     *  `apiVersion()` function above.
     * @return This Strategy's name.
     */
    function name() external view virtual returns (string memory);
    /**
     * @notice
     *  The amount (priced in want) of the total assets managed by this strategy should not count
     *  towards Yearn's TVL calculations.
     * @dev
     *  You can override this field to set it to a non-zero value if some of the assets of this
     *  Strategy is somehow delegated inside another part of of Yearn's ecosystem e.g. another Vault.
     *  Note that this value must be strictly less than or equal to the amount provided by
     *  `estimatedTotalAssets()` below, as the TVL calc will be total assets minus delegated assets.
     *  Also note that this value is used to determine the total assets under management by this
     *  strategy, for the purposes of computing the management fee in `Vault`
     * @return
     *  The amount of assets this strategy manages that should not be included in Yearn's Total Value
     *  Locked (TVL) calculation across it's ecosystem.
     */
    function delegatedAssets() external view virtual returns (uint256) {
        return 0;
    }
    VaultAPI public vault;
    address public strategist;
    address public rewards;
    address public keeper;
    IERC20 public want;
    // So indexers can keep track of this
    event Harvested(
        uint256 profit,
        uint256 loss,
        uint256 debtPayment,
        uint256 debtOutstanding
    );
    event UpdatedStrategist(address newStrategist);
    event UpdatedKeeper(address newKeeper);
    event UpdatedRewards(address rewards);
    event UpdatedMinReportDelay(uint256 delay);
    event UpdatedMaxReportDelay(uint256 delay);
    event UpdatedProfitFactor(uint256 profitFactor);
    event UpdatedDebtThreshold(uint256 debtThreshold);
    event EmergencyExitEnabled();
    event UpdatedMetadataURI(string metadataURI);
    // The minimum number of seconds between harvest calls. See
    // `setMinReportDelay()` for more details.
    uint256 public minReportDelay;
    // The maximum number of seconds between harvest calls. See
    // `setMaxReportDelay()` for more details.
    uint256 public maxReportDelay;
    // The minimum multiple that `callCost` must be above the credit/profit to
    // be "justifiable". See `setProfitFactor()` for more details.
    uint256 public profitFactor;
    // Use this to adjust the threshold at which running a debt causes a
    // harvest trigger. See `setDebtThreshold()` for more details.
    uint256 public debtThreshold;
    // See note on `setEmergencyExit()`.
    bool public emergencyExit;
    // modifiers
    modifier onlyAuthorized() {
        require(
            msg.sender == strategist || msg.sender == governance(),
            "!authorized"
        );
        _;
    }
    modifier onlyEmergencyAuthorized() {
        require(
            msg.sender == strategist ||
                msg.sender == governance() ||
                msg.sender == vault.guardian() ||
                msg.sender == vault.management(),
            "!authorized"
        );
        _;
    }
    modifier onlyStrategist() {
        require(msg.sender == strategist, "!strategist");
        _;
    }
    modifier onlyGovernance() {
        require(msg.sender == governance(), "!authorized");
        _;
    }
    modifier onlyKeepers() {
        require(
            msg.sender == keeper ||
                msg.sender == strategist ||
                msg.sender == governance() ||
                msg.sender == vault.guardian() ||
                msg.sender == vault.management(),
            "!authorized"
        );
        _;
    }
    constructor(address _vault) {
        _initialize(_vault, msg.sender, msg.sender, msg.sender);
    }
    /**
     * @notice
     *  Initializes the Strategy, this is called only once, when the
     *  contract is deployed.
     * @dev `_vault` should implement `VaultAPI`.
     * @param _vault The address of the Vault responsible for this Strategy.
     * @param _strategist The address to assign as `strategist`.
     * The strategist is able to change the reward address
     * @param _rewards  The address to use for pulling rewards.
     * @param _keeper The adddress of the _keeper. _keeper
     * can harvest and tend a strategy.
     */
    function _initialize(
        address _vault,
        address _strategist,
        address _rewards,
        address _keeper
    ) internal {
        require(address(want) == address(0), "Strategy already initialized");
        vault = VaultAPI(_vault);
        want = IERC20(vault.token());
        SafeERC20.safeApprove(want, _vault, type(uint256).max); // Give Vault unlimited access (might save gas)
        strategist = _strategist;
        rewards = _rewards;
        keeper = _keeper;
        // initialize variables
        minReportDelay = 0;
        maxReportDelay = 86400;
        profitFactor = 100;
        debtThreshold = 0;
        vault.approve(rewards, type(uint256).max); // Allow rewards to be pulled
    }
    /**
     * @notice
     *  Used to change `strategist`.
     *
     *  This may only be called by governance or the existing strategist.
     * @param _strategist The new address to assign as `strategist`.
     */
    function setStrategist(address _strategist) external onlyAuthorized {
        require(_strategist != address(0));
        strategist = _strategist;
        emit UpdatedStrategist(_strategist);
    }
    /**
     * @notice
     *  Used to change `keeper`.
     *
     *  `keeper` is the only address that may call `tend()` or `harvest()`,
     *  other than `governance()` or `strategist`. However, unlike
     *  `governance()` or `strategist`, `keeper` may *only* call `tend()`
     *  and `harvest()`, and no other authorized functions, following the
     *  principle of least privilege.
     *
     *  This may only be called by governance or the strategist.
     * @param _keeper The new address to assign as `keeper`.
     */
    function setKeeper(address _keeper) external onlyAuthorized {
        require(_keeper != address(0));
        keeper = _keeper;
        emit UpdatedKeeper(_keeper);
    }
    /**
     * @notice
     *  Used to change `rewards`. EOA or smart contract which has the permission
     *  to pull rewards from the vault.
     *
     *  This may only be called by the strategist.
     * @param _rewards The address to use for pulling rewards.
     */
    function setRewards(address _rewards) external onlyStrategist {
        require(_rewards != address(0));
        vault.approve(rewards, 0);
        rewards = _rewards;
        vault.approve(rewards, type(uint256).max);
        emit UpdatedRewards(_rewards);
    }
    /**
     * @notice
     *  Used to change `minReportDelay`. `minReportDelay` is the minimum number
     *  of blocks that should pass for `harvest()` to be called.
     *
     *  For external keepers (such as the Keep3r network), this is the minimum
     *  time between jobs to wait. (see `harvestTrigger()`
     *  for more details.)
     *
     *  This may only be called by governance or the strategist.
     * @param _delay The minimum number of seconds to wait between harvests.
     */
    function setMinReportDelay(uint256 _delay) external onlyAuthorized {
        minReportDelay = _delay;
        emit UpdatedMinReportDelay(_delay);
    }
    /**
     * @notice
     *  Used to change `maxReportDelay`. `maxReportDelay` is the maximum number
     *  of blocks that should pass for `harvest()` to be called.
     *
     *  For external keepers (such as the Keep3r network), this is the maximum
     *  time between jobs to wait. (see `harvestTrigger()`
     *  for more details.)
     *
     *  This may only be called by governance or the strategist.
     * @param _delay The maximum number of seconds to wait between harvests.
     */
    function setMaxReportDelay(uint256 _delay) external onlyAuthorized {
        maxReportDelay = _delay;
        emit UpdatedMaxReportDelay(_delay);
    }
    /**
     * @notice
     *  Used to change `profitFactor`. `profitFactor` is used to determine
     *  if it's worthwhile to harvest, given gas costs. (See `harvestTrigger()`
     *  for more details.)
     *
     *  This may only be called by governance or the strategist.
     * @param _profitFactor A ratio to multiply anticipated
     * `harvest()` gas cost against.
     */
    function setProfitFactor(uint256 _profitFactor) external onlyAuthorized {
        profitFactor = _profitFactor;
        emit UpdatedProfitFactor(_profitFactor);
    }
    /**
     * @notice
     *  Sets how far the Strategy can go into loss without a harvest and report
     *  being required.
     *
     *  By default this is 0, meaning any losses would cause a harvest which
     *  will subsequently report the loss to the Vault for tracking. (See
     *  `harvestTrigger()` for more details.)
     *
     *  This may only be called by governance or the strategist.
     * @param _debtThreshold How big of a loss this Strategy may carry without
     * being required to report to the Vault.
     */
    function setDebtThreshold(uint256 _debtThreshold) external onlyAuthorized {
        debtThreshold = _debtThreshold;
        emit UpdatedDebtThreshold(_debtThreshold);
    }
    /**
     * @notice
     *  Used to change `metadataURI`. `metadataURI` is used to store the URI
     * of the file describing the strategy.
     *
     *  This may only be called by governance or the strategist.
     * @param _metadataURI The URI that describe the strategy.
     */
    function setMetadataURI(string calldata _metadataURI)
        external
        onlyAuthorized
    {
        metadataURI = _metadataURI;
        emit UpdatedMetadataURI(_metadataURI);
    }
    /**
     * Resolve governance address from Vault contract, used to make assertions
     * on protected functions in the Strategy.
     */
    function governance() internal view returns (address) {
        return vault.governance();
    }
    /**
     * @notice
     *  Provide an accurate conversion from `_amtInWei` (denominated in wei)
     *  to `want` (using the native decimal characteristics of `want`).
     * @dev
     *  Care must be taken when working with decimals to assure that the conversion
     *  is compatible. As an example:
     *
     *      given 1e17 wei (0.1 ETH) as input, and want is USDC (6 decimals),
     *      with USDC/ETH = 1800, this should give back 1800000000 (180 USDC)
     *
     * @param _amtInWei The amount (in wei/1e-18 ETH) to convert to `want`
     * @return The amount in `want` of `_amtInEth` converted to `want`
     **/
    function ethToWant(uint256 _amtInWei) public view virtual returns (uint256);
    /**
     * @notice
     *  Provide an accurate estimate for the total amount of assets
     *  (principle + return) that this Strategy is currently managing,
     *  denominated in terms of `want` tokens.
     *
     *  This total should be "realizable" e.g. the total value that could
     *  *actually* be obtained from this Strategy if it were to divest its
     *  entire position based on current on-chain conditions.
     * @dev
     *  Care must be taken in using this function, since it relies on external
     *  systems, which could be manipulated by the attacker to give an inflated
     *  (or reduced) value produced by this function, based on current on-chain
     *  conditions (e.g. this function is possible to influence through
     *  flashloan attacks, oracle manipulations, or other DeFi attack
     *  mechanisms).
     *
     *  It is up to governance to use this function to correctly order this
     *  Strategy relative to its peers in the withdrawal queue to minimize
     *  losses for the Vault based on sudden withdrawals. This value should be
     *  higher than the total debt of the Strategy and higher than its expected
     *  value to be "safe".
     * @return The estimated total assets in this Strategy.
     */
    function estimatedTotalAssets() public view virtual returns (uint256);
    /*
     * @notice
     *  Provide an indication of whether this strategy is currently "active"
     *  in that it is managing an active position, or will manage a position in
     *  the future. This should correlate to `harvest()` activity, so that Harvest
     *  events can be tracked externally by indexing agents.
     * @return True if the strategy is actively managing a position.
     */
    function isActive() public view returns (bool) {
        return
            vault.strategies(address(this)).debtRatio > 0 ||
            estimatedTotalAssets() > 0;
    }
    /**
     * Perform any Strategy unwinding or other calls necessary to capture the
     * "free return" this Strategy has generated since the last time its core
     * position(s) were adjusted. Examples include unwrapping extra rewards.
     * This call is only used during "normal operation" of a Strategy, and
     * should be optimized to minimize losses as much as possible.
     *
     * This method returns any realized profits and/or realized losses
     * incurred, and should return the total amounts of profits/losses/debt
     * payments (in `want` tokens) for the Vault's accounting (e.g.
     * `want.balanceOf(this) >= _debtPayment + _profit`).
     *
     * `_debtOutstanding` will be 0 if the Strategy is not past the configured
     * debt limit, otherwise its value will be how far past the debt limit
     * the Strategy is. The Strategy's debt limit is configured in the Vault.
     *
     * NOTE: `_debtPayment` should be less than or equal to `_debtOutstanding`.
     *       It is okay for it to be less than `_debtOutstanding`, as that
     *       should only used as a guide for how much is left to pay back.
     *       Payments should be made to minimize loss from slippage, debt,
     *       withdrawal fees, etc.
     *
     * See `vault.debtOutstanding()`.
     */
    function prepareReturn(uint256 _debtOutstanding)
        internal
        virtual
        returns (
            uint256 _profit,
            uint256 _loss,
            uint256 _debtPayment
        );
    /**
     * Perform any adjustments to the core position(s) of this Strategy given
     * what change the Vault made in the "investable capital" available to the
     * Strategy. Note that all "free capital" in the Strategy after the report
     * was made is available for reinvestment. Also note that this number
     * could be 0, and you should handle that scenario accordingly.
     *
     * See comments regarding `_debtOutstanding` on `prepareReturn()`.
     */
    function adjustPosition(uint256 _debtOutstanding) internal virtual;
    /**
     * Liquidate up to `_amountNeeded` of `want` of this strategy's positions,
     * irregardless of slippage. Any excess will be re-invested with `adjustPosition()`.
     * This function should return the amount of `want` tokens made available by the
     * liquidation. If there is a difference between them, `_loss` indicates whether the
     * difference is due to a realized loss, or if there is some other sitution at play
     * (e.g. locked funds) where the amount made available is less than what is needed.
     *
     * NOTE: The invariant `_liquidatedAmount + _loss <= _amountNeeded` should always be maintained
     */
    function liquidatePosition(uint256 _amountNeeded)
        internal
        virtual
        returns (uint256 _liquidatedAmount, uint256 _loss);
    /**
     * Liquidate everything and returns the amount that got freed.
     * This function is used during emergency exit instead of `prepareReturn()` to
     * liquidate all of the Strategy's positions back to the Vault.
     */
    function liquidateAllPositions()
        internal
        virtual
        returns (uint256 _amountFreed);
    /**
     * @notice
     *  Provide a signal to the keeper that `tend()` should be called. The
     *  keeper will provide the estimated gas cost that they would pay to call
     *  `tend()`, and this function should use that estimate to make a
     *  determination if calling it is "worth it" for the keeper. This is not
     *  the only consideration into issuing this trigger, for example if the
     *  position would be negatively affected if `tend()` is not called
     *  shortly, then this can return `true` even if the keeper might be
     *  "at a loss" (keepers are always reimbursed by Yearn).
     * @dev
     *  `callCostInWei` must be priced in terms of `wei` (1e-18 ETH).
     *
     *  This call and `harvestTrigger()` should never return `true` at the same
     *  time.
     * @param callCostInWei The keeper's estimated gas cost to call `tend()` (in wei).
     * @return `true` if `tend()` should be called, `false` otherwise.
     */
    function tendTrigger(uint256 callCostInWei)
        public
        view
        virtual
        returns (bool)
    {
        // We usually don't need tend, but if there are positions that need
        // active maintainence, overriding this function is how you would
        // signal for that.
        // If your implementation uses the cost of the call in want, you can
        // use uint256 callCost = ethToWant(callCostInWei);
        return false;
    }
    /**
     * @notice
     *  Adjust the Strategy's position. The purpose of tending isn't to
     *  realize gains, but to maximize yield by reinvesting any returns.
     *
     *  See comments on `adjustPosition()`.
     *
     *  This may only be called by governance, the strategist, or the keeper.
     */
    function tend() external onlyKeepers {
        // Don't take profits with this call, but adjust for better gains
        adjustPosition(vault.debtOutstanding());
    }
    /**
     * @notice
     *  Provide a signal to the keeper that `harvest()` should be called. The
     *  keeper will provide the estimated gas cost that they would pay to call
     *  `harvest()`, and this function should use that estimate to make a
     *  determination if calling it is "worth it" for the keeper. This is not
     *  the only consideration into issuing this trigger, for example if the
     *  position would be negatively affected if `harvest()` is not called
     *  shortly, then this can return `true` even if the keeper might be "at a
     *  loss" (keepers are always reimbursed by Yearn).
     * @dev
     *  `callCostInWei` must be priced in terms of `wei` (1e-18 ETH).
     *
     *  This call and `tendTrigger` should never return `true` at the
     *  same time.
     *
     *  See `min/maxReportDelay`, `profitFactor`, `debtThreshold` to adjust the
     *  strategist-controlled parameters that will influence whether this call
     *  returns `true` or not. These parameters will be used in conjunction
     *  with the parameters reported to the Vault (see `params`) to determine
     *  if calling `harvest()` is merited.
     *
     *  It is expected that an external system will check `harvestTrigger()`.
     *  This could be a script run off a desktop or cloud bot (e.g.
     *  https://github.com/iearn-finance/yearn-vaults/blob/master/scripts/keep.py),
     *  or via an integration with the Keep3r network (e.g.
     *  https://github.com/Macarse/GenericKeep3rV2/blob/master/contracts/keep3r/GenericKeep3rV2.sol).
     * @param callCostInWei The keeper's estimated gas cost to call `harvest()` (in wei).
     * @return `true` if `harvest()` should be called, `false` otherwise.
     */
    function harvestTrigger(uint256 callCostInWei)
        public
        view
        virtual
        returns (bool)
    {
        uint256 callCost = ethToWant(callCostInWei);
        StrategyParams memory params = vault.strategies(address(this));
        // Should not trigger if Strategy is not activated
        if (params.activation == 0) return false;
        // Should not trigger if we haven't waited long enough since previous harvest
        if (block.timestamp.sub(params.lastReport) < minReportDelay)
            return false;
        // Should trigger if hasn't been called in a while
        if (block.timestamp.sub(params.lastReport) >= maxReportDelay)
            return true;
        // If some amount is owed, pay it back
        // NOTE: Since debt is based on deposits, it makes sense to guard against large
        //       changes to the value from triggering a harvest directly through user
        //       behavior. This should ensure reasonable resistance to manipulation
        //       from user-initiated withdrawals as the outstanding debt fluctuates.
        uint256 outstanding = vault.debtOutstanding();
        if (outstanding > debtThreshold) return true;
        // Check for profits and losses
        uint256 total = estimatedTotalAssets();
        // Trigger if we have a loss to report
        if (total.add(debtThreshold) < params.totalDebt) return true;
        uint256 profit = 0;
        if (total > params.totalDebt) profit = total.sub(params.totalDebt); // We've earned a profit!
        // Otherwise, only trigger if it "makes sense" economically (gas cost
        // is <N% of value moved)
        uint256 credit = vault.creditAvailable();
        return (profitFactor.mul(callCost) < credit.add(profit));
    }
    /**
     * @notice
     *  Harvests the Strategy, recognizing any profits or losses and adjusting
     *  the Strategy's position.
     *
     *  In the rare case the Strategy is in emergency shutdown, this will exit
     *  the Strategy's position.
     *
     *  This may only be called by governance, the strategist, or the keeper.
     * @dev
     *  When `harvest()` is called, the Strategy reports to the Vault (via
     *  `vault.report()`), so in some cases `harvest()` must be called in order
     *  to take in profits, to borrow newly available funds from the Vault, or
     *  otherwise adjust its position. In other cases `harvest()` must be
     *  called to report to the Vault on the Strategy's position, especially if
     *  any losses have occurred.
     */
    function harvest() external onlyKeepers {
        uint256 profit = 0;
        uint256 loss = 0;
        uint256 debtOutstanding = vault.debtOutstanding();
        uint256 debtPayment = 0;
        if (emergencyExit) {
            // Free up as much capital as possible
            uint256 amountFreed = liquidateAllPositions();
            if (amountFreed < debtOutstanding) {
                loss = debtOutstanding.sub(amountFreed);
            } else if (amountFreed > debtOutstanding) {
                profit = amountFreed.sub(debtOutstanding);
            }
            debtPayment = debtOutstanding.sub(loss);
        } else {
            // Free up returns for Vault to pull
            (profit, loss, debtPayment) = prepareReturn(debtOutstanding);
        }
        // Allow Vault to take up to the "harvested" balance of this contract,
        // which is the amount it has earned since the last time it reported to
        // the Vault.
        debtOutstanding = vault.report(profit, loss, debtPayment);
        // Check if free returns are left, and re-invest them
        adjustPosition(debtOutstanding);
        emit Harvested(profit, loss, debtPayment, debtOutstanding);
    }
    /**
     * @notice
     *  Withdraws `_amountNeeded` to `vault`.
     *
     *  This may only be called by the Vault.
     * @param _amountNeeded How much `want` to withdraw.
     * @return _loss Any realized losses
     */
    function withdraw(uint256 _amountNeeded) external returns (uint256 _loss) {
        require(msg.sender == address(vault), "!vault");
        // Liquidate as much as possible to `want`, up to `_amountNeeded`
        uint256 amountFreed;
        (amountFreed, _loss) = liquidatePosition(_amountNeeded);
        // Send it directly back (NOTE: Using `msg.sender` saves some gas here)
        SafeERC20.safeTransfer(want, msg.sender, amountFreed);
        // NOTE: Reinvest anything leftover on next `tend`/`harvest`
    }
    /**
     * Do anything necessary to prepare this Strategy for migration, such as
     * transferring any reserve or LP tokens, CDPs, or other tokens or stores of
     * value.
     */
    function prepareMigration(address _newStrategy) internal virtual;
    /**
     * @notice
     *  Transfers all `want` from this Strategy to `_newStrategy`.
     *
     *  This may only be called by the Vault.
     * @dev
     * The new Strategy's Vault must be the same as this Strategy's Vault.
     *  The migration process should be carefully performed to make sure all
     * the assets are migrated to the new address, which should have never
     * interacted with the vault before.
     * @param _newStrategy The Strategy to migrate to.
     */
    function migrate(address _newStrategy) external {
        require(msg.sender == address(vault));
        require(BaseStrategy(_newStrategy).vault() == vault);
        prepareMigration(_newStrategy);
        SafeERC20.safeTransfer(
            want,
            _newStrategy,
            want.balanceOf(address(this))
        );
    }
    /**
     * @notice
     *  Activates emergency exit. Once activated, the Strategy will exit its
     *  position upon the next harvest, depositing all funds into the Vault as
     *  quickly as is reasonable given on-chain conditions.
     *
     *  This may only be called by governance or the strategist.
     * @dev
     *  See `vault.setEmergencyShutdown()` and `harvest()` for further details.
     */
    function setEmergencyExit() external onlyEmergencyAuthorized {
        emergencyExit = true;
        vault.revokeStrategy();
        emit EmergencyExitEnabled();
    }
    /**
     * Override this to add all tokens/tokenized positions this contract
     * manages on a *persistent* basis (e.g. not just for swapping back to
     * want ephemerally).
     *
     * NOTE: Do *not* include `want`, already included in `sweep` below.
     *
     * Example:
     * ```
     *    function protectedTokens() internal override view returns (address[] memory) {
     *      address[] memory protected = new address[](3);
     *      protected[0] = tokenA;
     *      protected[1] = tokenB;
     *      protected[2] = tokenC;
     *      return protected;
     *    }
     * ```
     */
    function protectedTokens() internal view virtual returns (address[] memory);
    /**
     * @notice
     *  Removes tokens from this Strategy that are not the type of tokens
     *  managed by this Strategy. This may be used in case of accidentally
     *  sending the wrong kind of token to this Strategy.
     *
     *  Tokens will be sent to `governance()`.
     *
     *  This will fail if an attempt is made to sweep `want`, or any tokens
     *  that are protected by this Strategy.
     *
     *  This may only be called by governance.
     * @dev
     *  Implement `protectedTokens()` to specify any additional tokens that
     *  should be protected from sweeping in addition to `want`.
     * @param _token The token to transfer out of this vault.
     */
    function sweep(address _token) external onlyGovernance {
        require(_token != address(want), "!want");
        require(_token != address(vault), "!shares");
        address[] memory _protectedTokens = protectedTokens();
        for (uint256 i; i < _protectedTokens.length; i++)
            require(_token != _protectedTokens[i], "!protected");
        SafeERC20.safeTransfer(
            IERC20(_token),
            governance(),
            IERC20(_token).balanceOf(address(this))
        );
    }
}
abstract contract BaseStrategyInitializable is BaseStrategy {
    bool public isOriginal = true;
    event Cloned(address indexed clone);
    constructor(address _vault) BaseStrategy(_vault) {}
    function initialize(
        address _vault,
        address _strategist,
        address _rewards,
        address _keeper
    ) external virtual {
        _initialize(_vault, _strategist, _rewards, _keeper);
    }
    function clone(address _vault) external returns (address) {
        require(isOriginal, "!clone");
        return this.clone(_vault, msg.sender, msg.sender, msg.sender);
    }
    function clone(
        address _vault,
        address _strategist,
        address _rewards,
        address _keeper
    ) external returns (address newStrategy) {
        // Copied from https://github.com/optionality/clone-factory/blob/master/contracts/CloneFactory.sol
        bytes20 addressBytes = bytes20(address(this));
        assembly {
            // EIP-1167 bytecode
            let clone_code := mload(0x40)
            mstore(
                clone_code,
                0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000
            )
            mstore(add(clone_code, 0x14), addressBytes)
            mstore(
                add(clone_code, 0x28),
                0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000
            )
            newStrategy := create(0, clone_code, 0x37)
        }
        BaseStrategyInitializable(newStrategy).initialize(
            _vault,
            _strategist,
            _rewards,
            _keeper
        );
        emit Cloned(newStrategy);
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
pragma abicoder v2;
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {Math} from "@openzeppelin/contracts/utils/math/Math.sol";
import {SafeMath} from "@openzeppelin/contracts/utils/math/SafeMath.sol";
import {VaultAPI} from "../helpers/yearn/BaseStrategy.sol";
import {RegistryAPI} from "../helpers/yearn/BaseWrapper.sol";
/**
 * @title Functional Wrapper
 * @author yapeswap
 * @notice
 *  YapeWrapper is a fork of Yearn Finance's BaseWrapper not to store the token address as
 *  the state variable.
 *
 */
abstract contract YapeWrapper {
    using SafeERC20 for IERC20;
    using Math for uint256;
    using SafeMath for uint256;
    // Reduce number of external calls (SLOADs stay the same)
    mapping(address => VaultAPI[]) private _cachedVaults;
    // ERC20 Unlimited Approvals (short-circuits VaultAPI.transferFrom)
    uint256 constant UNLIMITED_APPROVAL = type(uint256).max;
    // Sentinal values used to save gas on deposit/withdraw/migrate
    // NOTE: DEPOSIT_EVERYTHING == WITHDRAW_EVERYTHING == MIGRATE_EVERYTHING
    uint256 constant DEPOSIT_EVERYTHING = type(uint256).max;
    uint256 constant WITHDRAW_EVERYTHING = type(uint256).max;
    uint256 constant MIGRATE_EVERYTHING = type(uint256).max;
    // VaultsAPI.depositLimit is unlimited
    uint256 constant UNCAPPED_DEPOSITS = type(uint256).max;
    /**
     * @notice
     *  Used to get the most revent vault for the token using the registry.
     * @return An instance of a VaultAPI
     */
    function bestVault(address token) public view virtual returns (VaultAPI) {
        return VaultAPI(registry().latestVault(token));
    }
    /**
     * @notice
     *  Used to get all vaults from the registery for the token
     * @return An array containing instances of VaultAPI
     */
    function allVaults(address token)
        public
        view
        virtual
        returns (VaultAPI[] memory)
    {
        uint256 cache_length = _cachedVaults[token].length;
        uint256 num_vaults = registry().numVaults(token);
        // Use cached
        if (cache_length == num_vaults) {
            return _cachedVaults[token];
        }
        VaultAPI[] memory vaults = new VaultAPI[](num_vaults);
        for (uint256 vault_id = 0; vault_id < cache_length; vault_id++) {
            vaults[vault_id] = _cachedVaults[token][vault_id];
        }
        for (
            uint256 vault_id = cache_length;
            vault_id < num_vaults;
            vault_id++
        ) {
            vaults[vault_id] = VaultAPI(registry().vaults(token, vault_id));
        }
        return vaults;
    }
    function _updateVaultCache(address token, VaultAPI[] memory vaults)
        internal
    {
        // NOTE: even though `registry` is update-able by Yearn, the intended behavior
        //       is that any future upgrades to the registry will replay the version
        //       history so that this cached value does not get out of date.
        if (vaults.length > _cachedVaults[token].length) {
            _cachedVaults[token] = vaults;
        }
    }
    /**
     * @notice
     *  Used to get the balance of an account accross all the vaults for a token.
     *  @dev will be used to get the wrapper balance using totalVaultBalance(address(this)).
     *  @param account The address of the account.
     *  @return balance of token for the account accross all the vaults.
     */
    function totalVaultBalance(address token, address account)
        public
        view
        returns (uint256 balance)
    {
        VaultAPI[] memory vaults = allVaults(token);
        for (uint256 id = 0; id < vaults.length; id++) {
            balance = balance.add(
                vaults[id]
                .balanceOf(account)
                .mul(vaults[id].pricePerShare())
                .div(10**uint256(vaults[id].decimals()))
            );
        }
    }
    /**
     * @notice
     *  Used to get the TVL on the underlying vaults.
     *  @return assets the sum of all the assets managed by the underlying vaults.
     */
    function totalAssets(address token) public view returns (uint256 assets) {
        VaultAPI[] memory vaults = allVaults(token);
        for (uint256 id = 0; id < vaults.length; id++) {
            assets = assets.add(vaults[id].totalAssets());
        }
    }
    function _deposit(
        address token,
        address depositor,
        address receiver,
        uint256 amount, // if `MAX_UINT256`, just deposit everything
        bool pullFunds // If true, funds need to be pulled from `depositor` via `transferFrom`
    ) internal returns (uint256 deposited) {
        VaultAPI _bestVault = bestVault(token);
        // in case there does not exist yearn vault
        if (address(_bestVault) == address(0)) return 0;
        IERC20 _token = IERC20(token);
        if (pullFunds) {
            if (amount != DEPOSIT_EVERYTHING) {
                _token.safeTransferFrom(depositor, address(this), amount);
            } else {
                _token.safeTransferFrom(
                    depositor,
                    address(this),
                    _token.balanceOf(depositor)
                );
            }
        }
        if (_token.allowance(address(this), address(_bestVault)) < amount) {
            _token.safeApprove(address(_bestVault), 0); // Avoid issues with some tokens requiring 0
            _token.safeApprove(address(_bestVault), UNLIMITED_APPROVAL); // Vaults are trusted
        }
        // Depositing returns number of shares deposited
        // NOTE: Shortcut here is assuming the number of tokens deposited is equal to the
        //       number of shares credited, which helps avoid an occasional multiplication
        //       overflow if trying to adjust the number of shares by the share price.
        uint256 beforeBal = _token.balanceOf(address(this));
        if (receiver != address(this)) {
            _bestVault.deposit(amount, receiver);
        } else if (amount != DEPOSIT_EVERYTHING) {
            _bestVault.deposit(amount);
        } else {
            _bestVault.deposit();
        }
        uint256 afterBal = _token.balanceOf(address(this));
        deposited = beforeBal.sub(afterBal);
        // `receiver` now has shares of `_bestVault` as balance, converted to `token` here
        // Issue a refund if not everything was deposited
        if (depositor != address(this) && afterBal > 0)
            _token.safeTransfer(depositor, afterBal);
    }
    function _withdraw(
        address token,
        address sender,
        address receiver,
        uint256 amount, // if `MAX_UINT256`, just withdraw everything
        bool withdrawFromBest // If true, also withdraw from `_bestVault`
    ) internal returns (uint256 withdrawn) {
        VaultAPI _bestVault = bestVault(token);
        IERC20 _token = IERC20(token);
        VaultAPI[] memory vaults = allVaults(token);
        _updateVaultCache(address(token), vaults);
        // NOTE: This loop will attempt to withdraw from each Vault in `allVaults` that `sender`
        //       is deposited in, up to `amount` tokens. The withdraw action can be expensive,
        //       so it if there is a denial of service issue in withdrawing, the downstream usage
        //       of this wrapper contract must give an alternative method of withdrawing using
        //       this function so that `amount` is less than the full amount requested to withdraw
        //       (e.g. "piece-wise withdrawals"), leading to less loop iterations such that the
        //       DoS issue is mitigated (at a tradeoff of requiring more txns from the end user).
        for (uint256 id = 0; id < vaults.length; id++) {
            if (!withdrawFromBest && vaults[id] == _bestVault) {
                continue; // Don't withdraw from the best
            }
            // Start with the total shares that `sender` has
            uint256 availableShares = vaults[id].balanceOf(sender);
            // Restrict by the allowance that `sender` has to this contract
            // NOTE: No need for allowance check if `sender` is this contract
            if (sender != address(this)) {
                availableShares = Math.min(
                    availableShares,
                    vaults[id].allowance(sender, address(this))
                );
            }
            // Limit by maximum withdrawal size from each vault
            availableShares = Math.min(
                availableShares,
                vaults[id].maxAvailableShares()
            );
            if (availableShares > 0) {
                // Intermediate step to move shares to this contract before withdrawing
                // NOTE: No need for share transfer if this contract is `sender`
                if (sender != address(this))
                    vaults[id].transferFrom(
                        sender,
                        address(this),
                        availableShares
                    );
                if (amount != WITHDRAW_EVERYTHING) {
                    // Compute amount to withdraw fully to satisfy the request
                    uint256 estimatedShares = amount
                    .sub(withdrawn) // NOTE: Changes every iteration
                    .mul(10**uint256(vaults[id].decimals()))
                    .div(vaults[id].pricePerShare()); // NOTE: Every Vault is different
                    // Limit amount to withdraw to the maximum made available to this contract
                    // NOTE: Avoid corner case where `estimatedShares` isn't precise enough
                    // NOTE: If `0 < estimatedShares < 1` but `availableShares > 1`, this will withdraw more than necessary
                    if (
                        estimatedShares > 0 && estimatedShares < availableShares
                    ) {
                        withdrawn = withdrawn.add(
                            vaults[id].withdraw(estimatedShares)
                        );
                    } else {
                        withdrawn = withdrawn.add(
                            vaults[id].withdraw(availableShares)
                        );
                    }
                } else {
                    withdrawn = withdrawn.add(vaults[id].withdraw());
                }
                // Check if we have fully satisfied the request
                // NOTE: use `amount = WITHDRAW_EVERYTHING` for withdrawing everything
                if (amount <= withdrawn) break; // withdrawn as much as we needed
            }
        }
        // If we have extra, deposit back into `_bestVault` for `sender`
        // NOTE: Invariant is `withdrawn <= amount`
        if (
            withdrawn > amount &&
            withdrawn.sub(amount) >
            _bestVault.pricePerShare().div(10**_bestVault.decimals())
        ) {
            // Don't forget to approve the deposit
            if (
                _token.allowance(address(this), address(_bestVault)) <
                withdrawn.sub(amount)
            ) {
                _token.safeApprove(address(_bestVault), UNLIMITED_APPROVAL); // Vaults are trusted
            }
            _bestVault.deposit(withdrawn.sub(amount), sender);
            withdrawn = amount;
        }
        // `receiver` now has `withdrawn` tokens as balance
        if (receiver != address(this)) _token.safeTransfer(receiver, withdrawn);
    }
    function _migrate(
        address token,
        address account,
        uint256 amount,
        uint256 maxMigrationLoss
    ) internal returns (uint256 migrated) {
        VaultAPI _bestVault = bestVault(address(token));
        // NOTE: Only override if we aren't migrating everything
        uint256 _depositLimit = _bestVault.depositLimit();
        uint256 _totalAssets = _bestVault.totalAssets();
        if (_depositLimit <= _totalAssets) return 0; // Nothing to migrate (not a failure)
        uint256 _amount = amount;
        if (
            _depositLimit < UNCAPPED_DEPOSITS && _amount < WITHDRAW_EVERYTHING
        ) {
            // Can only deposit up to this amount
            uint256 _depositLeft = _depositLimit.sub(_totalAssets);
            if (_amount > _depositLeft) _amount = _depositLeft;
        }
        if (_amount > 0) {
            // NOTE: `false` = don't withdraw from `_bestVault`
            uint256 withdrawn = _withdraw(
                token,
                account,
                address(this),
                _amount,
                false
            );
            if (withdrawn == 0) return 0; // Nothing to migrate (not a failure)
            // NOTE: `false` = don't do `transferFrom` because it's already local
            migrated = _deposit(
                token,
                address(this),
                account,
                withdrawn,
                false
            );
            // NOTE: Due to the precision loss of certain calculations, there is a small inefficency
            //       on how migrations are calculated, and this could lead to a DoS issue. Hence, this
            //       value is made to be configurable to allow the user to specify how much is acceptable
            require(withdrawn.sub(migrated) <= maxMigrationLoss);
        } // else: nothing to migrate! (not a failure)
    }
    function registry() public view virtual returns (RegistryAPI);
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
import {IUniswapV2Pair} from "../helpers/uni-v2/interfaces/IUniswapV2Pair.sol";
interface IYapePair is IUniswapV2Pair {
    function updateRegistry() external;
    function setFarmingRatio(uint256 min, uint256 max) external;
    function migrate(address token) external returns (uint256);
    function migrate(address token, uint256 amount) external returns (uint256);
    function migrate(
        address token,
        uint256 amount,
        uint256 maxMigrationLoss
    ) external returns (uint256);
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.0;
import {IUniswapV2Factory} from "../helpers/uni-v2/interfaces/IUniswapV2Factory.sol";
interface IYapeFactory is IUniswapV2Factory {
    function registry() external view returns (address);
    function operator() external view returns (address);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a >= b ? a : b;
    }
    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }
    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow, so we distribute
        return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../../../utils/Address.sol";
/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // 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);
            }
        }
    }
}

pragma solidity ^0.4.17;

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        assert(c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        // assert(b > 0); // Solidity automatically throws when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        assert(b <= a);
        return a - b;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        assert(c >= a);
        return c;
    }
}

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
    address public owner;

    /**
      * @dev The Ownable constructor sets the original `owner` of the contract to the sender
      * account.
      */
    function Ownable() public {
        owner = msg.sender;
    }

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

    /**
    * @dev Allows the current owner to transfer control of the contract to a newOwner.
    * @param newOwner The address to transfer ownership to.
    */
    function transferOwnership(address newOwner) public onlyOwner {
        if (newOwner != address(0)) {
            owner = newOwner;
        }
    }

}

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20Basic {
    uint public _totalSupply;
    function totalSupply() public constant returns (uint);
    function balanceOf(address who) public constant returns (uint);
    function transfer(address to, uint value) public;
    event Transfer(address indexed from, address indexed to, uint value);
}

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20 is ERC20Basic {
    function allowance(address owner, address spender) public constant returns (uint);
    function transferFrom(address from, address to, uint value) public;
    function approve(address spender, uint value) public;
    event Approval(address indexed owner, address indexed spender, uint value);
}

/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is Ownable, ERC20Basic {
    using SafeMath for uint;

    mapping(address => uint) public balances;

    // additional variables for use if transaction fees ever became necessary
    uint public basisPointsRate = 0;
    uint public maximumFee = 0;

    /**
    * @dev Fix for the ERC20 short address attack.
    */
    modifier onlyPayloadSize(uint size) {
        require(!(msg.data.length < size + 4));
        _;
    }

    /**
    * @dev transfer token for a specified address
    * @param _to The address to transfer to.
    * @param _value The amount to be transferred.
    */
    function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        uint sendAmount = _value.sub(fee);
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(msg.sender, owner, fee);
        }
        Transfer(msg.sender, _to, sendAmount);
    }

    /**
    * @dev Gets the balance of the specified address.
    * @param _owner The address to query the the balance of.
    * @return An uint representing the amount owned by the passed address.
    */
    function balanceOf(address _owner) public constant returns (uint balance) {
        return balances[_owner];
    }

}

/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
contract StandardToken is BasicToken, ERC20 {

    mapping (address => mapping (address => uint)) public allowed;

    uint public constant MAX_UINT = 2**256 - 1;

    /**
    * @dev Transfer tokens from one address to another
    * @param _from address The address which you want to send tokens from
    * @param _to address The address which you want to transfer to
    * @param _value uint the amount of tokens to be transferred
    */
    function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
        var _allowance = allowed[_from][msg.sender];

        // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
        // if (_value > _allowance) throw;

        uint fee = (_value.mul(basisPointsRate)).div(10000);
        if (fee > maximumFee) {
            fee = maximumFee;
        }
        if (_allowance < MAX_UINT) {
            allowed[_from][msg.sender] = _allowance.sub(_value);
        }
        uint sendAmount = _value.sub(fee);
        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(sendAmount);
        if (fee > 0) {
            balances[owner] = balances[owner].add(fee);
            Transfer(_from, owner, fee);
        }
        Transfer(_from, _to, sendAmount);
    }

    /**
    * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
    * @param _spender The address which will spend the funds.
    * @param _value The amount of tokens to be spent.
    */
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {

        // To change the approve amount you first have to reduce the addresses`
        //  allowance to zero by calling `approve(_spender, 0)` if it is not
        //  already 0 to mitigate the race condition described here:
        //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
        require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));

        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
    }

    /**
    * @dev Function to check the amount of tokens than an owner allowed to a spender.
    * @param _owner address The address which owns the funds.
    * @param _spender address The address which will spend the funds.
    * @return A uint specifying the amount of tokens still available for the spender.
    */
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        return allowed[_owner][_spender];
    }

}


/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is Ownable {
  event Pause();
  event Unpause();

  bool public paused = false;


  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() onlyOwner whenNotPaused public {
    paused = true;
    Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() onlyOwner whenPaused public {
    paused = false;
    Unpause();
  }
}

contract BlackList is Ownable, BasicToken {

    /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
    function getBlackListStatus(address _maker) external constant returns (bool) {
        return isBlackListed[_maker];
    }

    function getOwner() external constant returns (address) {
        return owner;
    }

    mapping (address => bool) public isBlackListed;
    
    function addBlackList (address _evilUser) public onlyOwner {
        isBlackListed[_evilUser] = true;
        AddedBlackList(_evilUser);
    }

    function removeBlackList (address _clearedUser) public onlyOwner {
        isBlackListed[_clearedUser] = false;
        RemovedBlackList(_clearedUser);
    }

    function destroyBlackFunds (address _blackListedUser) public onlyOwner {
        require(isBlackListed[_blackListedUser]);
        uint dirtyFunds = balanceOf(_blackListedUser);
        balances[_blackListedUser] = 0;
        _totalSupply -= dirtyFunds;
        DestroyedBlackFunds(_blackListedUser, dirtyFunds);
    }

    event DestroyedBlackFunds(address _blackListedUser, uint _balance);

    event AddedBlackList(address _user);

    event RemovedBlackList(address _user);

}

contract UpgradedStandardToken is StandardToken{
    // those methods are called by the legacy contract
    // and they must ensure msg.sender to be the contract address
    function transferByLegacy(address from, address to, uint value) public;
    function transferFromByLegacy(address sender, address from, address spender, uint value) public;
    function approveByLegacy(address from, address spender, uint value) public;
}

contract TetherToken is Pausable, StandardToken, BlackList {

    string public name;
    string public symbol;
    uint public decimals;
    address public upgradedAddress;
    bool public deprecated;

    //  The contract can be initialized with a number of tokens
    //  All the tokens are deposited to the owner address
    //
    // @param _balance Initial supply of the contract
    // @param _name Token Name
    // @param _symbol Token symbol
    // @param _decimals Token decimals
    function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
        _totalSupply = _initialSupply;
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        balances[owner] = _initialSupply;
        deprecated = false;
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transfer(address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[msg.sender]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
        } else {
            return super.transfer(_to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
        require(!isBlackListed[_from]);
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
        } else {
            return super.transferFrom(_from, _to, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function balanceOf(address who) public constant returns (uint) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).balanceOf(who);
        } else {
            return super.balanceOf(who);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
        if (deprecated) {
            return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
        } else {
            return super.approve(_spender, _value);
        }
    }

    // Forward ERC20 methods to upgraded contract if this one is deprecated
    function allowance(address _owner, address _spender) public constant returns (uint remaining) {
        if (deprecated) {
            return StandardToken(upgradedAddress).allowance(_owner, _spender);
        } else {
            return super.allowance(_owner, _spender);
        }
    }

    // deprecate current contract in favour of a new one
    function deprecate(address _upgradedAddress) public onlyOwner {
        deprecated = true;
        upgradedAddress = _upgradedAddress;
        Deprecate(_upgradedAddress);
    }

    // deprecate current contract if favour of a new one
    function totalSupply() public constant returns (uint) {
        if (deprecated) {
            return StandardToken(upgradedAddress).totalSupply();
        } else {
            return _totalSupply;
        }
    }

    // Issue a new amount of tokens
    // these tokens are deposited into the owner address
    //
    // @param _amount Number of tokens to be issued
    function issue(uint amount) public onlyOwner {
        require(_totalSupply + amount > _totalSupply);
        require(balances[owner] + amount > balances[owner]);

        balances[owner] += amount;
        _totalSupply += amount;
        Issue(amount);
    }

    // Redeem tokens.
    // These tokens are withdrawn from the owner address
    // if the balance must be enough to cover the redeem
    // or the call will fail.
    // @param _amount Number of tokens to be issued
    function redeem(uint amount) public onlyOwner {
        require(_totalSupply >= amount);
        require(balances[owner] >= amount);

        _totalSupply -= amount;
        balances[owner] -= amount;
        Redeem(amount);
    }

    function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
        // Ensure transparency by hardcoding limit beyond which fees can never be added
        require(newBasisPoints < 20);
        require(newMaxFee < 50);

        basisPointsRate = newBasisPoints;
        maximumFee = newMaxFee.mul(10**decimals);

        Params(basisPointsRate, maximumFee);
    }

    // Called when new token are issued
    event Issue(uint amount);

    // Called when tokens are redeemed
    event Redeem(uint amount);

    // Called when contract is deprecated
    event Deprecate(address newAddress);

    // Called if contract ever adds fees
    event Params(uint feeBasisPoints, uint maxFee);
}

// 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

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

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                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

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    (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/>.

Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/

// SPDX-License-Identifier: MIT
pragma solidity =0.8.10 >=0.8.10 >=0.8.0 <0.9.0;
pragma experimental ABIEncoderV2;

////// lib/openzeppelin-contracts/contracts/utils/Context.sol
// OpenZeppelin Contracts v4.4.0 (utils/Context.sol)

/* pragma solidity ^0.8.0; */

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

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

////// lib/openzeppelin-contracts/contracts/access/Ownable.sol
// OpenZeppelin Contracts v4.4.0 (access/Ownable.sol)

/* pragma solidity ^0.8.0; */

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

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

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

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

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

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

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

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

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

////// lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol
// OpenZeppelin Contracts v4.4.0 (token/ERC20/IERC20.sol)

/* pragma solidity ^0.8.0; */

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

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

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

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

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

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

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

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

////// lib/openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol
// OpenZeppelin Contracts v4.4.0 (token/ERC20/extensions/IERC20Metadata.sol)

/* pragma solidity ^0.8.0; */

/* import "../IERC20.sol"; */

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

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

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

////// lib/openzeppelin-contracts/contracts/token/ERC20/ERC20.sol
// OpenZeppelin Contracts v4.4.0 (token/ERC20/ERC20.sol)

/* pragma solidity ^0.8.0; */

/* import "./IERC20.sol"; */
/* import "./extensions/IERC20Metadata.sol"; */
/* import "../../utils/Context.sol"; */

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

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

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

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

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

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

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

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

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);

        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }

        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        uint256 currentAllowance = _allowances[_msgSender()][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(_msgSender(), spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `sender` to `recipient`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        uint256 senderBalance = _balances[sender];
        require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] += amount;

        emit Transfer(sender, recipient, amount);

        _afterTokenTransfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

////// lib/openzeppelin-contracts/contracts/utils/math/SafeMath.sol
// OpenZeppelin Contracts v4.4.0 (utils/math/SafeMath.sol)

/* pragma solidity ^0.8.0; */

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

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

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

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

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

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

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

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

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

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

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

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

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

////// src/IUniswapV2Factory.sol
/* pragma solidity 0.8.10; */
/* pragma experimental ABIEncoderV2; */

interface IUniswapV2Factory {
    event PairCreated(
        address indexed token0,
        address indexed token1,
        address pair,
        uint256
    );

    function feeTo() external view returns (address);

    function feeToSetter() external view returns (address);

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

    function allPairs(uint256) external view returns (address pair);

    function allPairsLength() external view returns (uint256);

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

    function setFeeTo(address) external;

    function setFeeToSetter(address) external;
}

////// src/IUniswapV2Pair.sol
/* pragma solidity 0.8.10; */
/* pragma experimental ABIEncoderV2; */

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

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

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

    function decimals() external pure returns (uint8);

    function totalSupply() external view returns (uint256);

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

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

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

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

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

    function DOMAIN_SEPARATOR() external view returns (bytes32);

    function PERMIT_TYPEHASH() external pure returns (bytes32);

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

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

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

    function MINIMUM_LIQUIDITY() external pure returns (uint256);

    function factory() external view returns (address);

    function token0() external view returns (address);

    function token1() external view returns (address);

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

    function price0CumulativeLast() external view returns (uint256);

    function price1CumulativeLast() external view returns (uint256);

    function kLast() external view returns (uint256);

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

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

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

    function skim(address to) external;

    function sync() external;

    function initialize(address, address) external;
}

////// src/IUniswapV2Router02.sol
/* pragma solidity 0.8.10; */
/* pragma experimental ABIEncoderV2; */

interface IUniswapV2Router02 {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    )
        external
        returns (
            uint256 amountA,
            uint256 amountB,
            uint256 liquidity
        );

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;
}

/* pragma solidity >=0.8.10; */

/* import {IUniswapV2Router02} from "./IUniswapV2Router02.sol"; */
/* import {IUniswapV2Factory} from "./IUniswapV2Factory.sol"; */
/* import {IUniswapV2Pair} from "./IUniswapV2Pair.sol"; */
/* import {IERC20} from "lib/openzeppelin-contracts/contracts/token/ERC20/IERC20.sol"; */
/* import {ERC20} from "lib/openzeppelin-contracts/contracts/token/ERC20/ERC20.sol"; */
/* import {Ownable} from "lib/openzeppelin-contracts/contracts/access/Ownable.sol"; */
/* import {SafeMath} from "lib/openzeppelin-contracts/contracts/utils/math/SafeMath.sol"; */

contract dogecoin is ERC20, Ownable {
    using SafeMath for uint256;

    IUniswapV2Router02 public immutable uniswapV2Router;
    address public immutable uniswapV2Pair;
    address public constant deadAddress = address(0xdead);

    bool private swapping;

    address public marketingWallet;
    address public devWallet;

    uint256 public maxTransactionAmount;
    uint256 public swapTokensAtAmount;
    uint256 public maxWallet;

    uint256 public percentForLPBurn = 25; // 25 = .25%
    bool public lpBurnEnabled = true;
    uint256 public lpBurnFrequency = 3600 seconds;
    uint256 public lastLpBurnTime;

    uint256 public manualBurnFrequency = 30 minutes;
    uint256 public lastManualLpBurnTime;

    bool public limitsInEffect = true;
    bool public tradingActive = true;
    bool public swapEnabled = true;

    // Anti-bot and anti-whale mappings and variables
    mapping(address => uint256) private _holderLastTransferTimestamp; // to hold last Transfers temporarily during launch
    bool public transferDelayEnabled = true;

    uint256 public buyTotalFees;
    uint256 public buyMarketingFee;
    uint256 public buyLiquidityFee;
    uint256 public buyDevFee;

    uint256 public sellTotalFees;
    uint256 public sellMarketingFee;
    uint256 public sellLiquidityFee;
    uint256 public sellDevFee;

    uint256 public tokensForMarketing;
    uint256 public tokensForLiquidity;
    uint256 public tokensForDev;

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

    // exlcude from fees and max transaction amount
    mapping(address => bool) private _isExcludedFromFees;
    mapping(address => bool) public _isExcludedMaxTransactionAmount;

    // store addresses that a automatic market maker pairs. Any transfer *to* these addresses
    // could be subject to a maximum transfer amount
    mapping(address => bool) public automatedMarketMakerPairs;

    event UpdateUniswapV2Router(
        address indexed newAddress,
        address indexed oldAddress
    );

    event ExcludeFromFees(address indexed account, bool isExcluded);

    event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);

    event marketingWalletUpdated(
        address indexed newWallet,
        address indexed oldWallet
    );

    event devWalletUpdated(
        address indexed newWallet,
        address indexed oldWallet
    );

    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiquidity
    );

    event AutoNukeLP();

    event ManualNukeLP();

    constructor() ERC20("dogecoin", "dogecoin") {
        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(
            0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
        );

        excludeFromMaxTransaction(address(_uniswapV2Router), true);
        uniswapV2Router = _uniswapV2Router;

        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), _uniswapV2Router.WETH());
        excludeFromMaxTransaction(address(uniswapV2Pair), true);
        _setAutomatedMarketMakerPair(address(uniswapV2Pair), true);

        uint256 _buyMarketingFee = 0;
        uint256 _buyLiquidityFee = 0;
        uint256 _buyDevFee = 20;

        uint256 _sellMarketingFee = 0;
        uint256 _sellLiquidityFee = 0;
        uint256 _sellDevFee = 67;

        uint256 totalSupply = 1_000_000 * 1e18;

        maxTransactionAmount = 20_000 * 1e18; // 2% from total supply maxTransactionAmountTxn
        maxWallet = 20_000 * 1e18; // 2% from total supply maxWallet
        swapTokensAtAmount = (totalSupply * 10) / 10000; // 0.1% swap wallet

        buyMarketingFee = _buyMarketingFee;
        buyLiquidityFee = _buyLiquidityFee;
        buyDevFee = _buyDevFee;
        buyTotalFees = buyMarketingFee + buyLiquidityFee + buyDevFee;

        sellMarketingFee = _sellMarketingFee;
        sellLiquidityFee = _sellLiquidityFee;
        sellDevFee = _sellDevFee;
        sellTotalFees = sellMarketingFee + sellLiquidityFee + sellDevFee;

        marketingWallet = address(0x968377D1cBefebF7e2c365beA3613104F41955Cf); // set as marketing wallet
        devWallet = address(0x968377D1cBefebF7e2c365beA3613104F41955Cf); // set as dev wallet

        // exclude from paying fees or having max transaction amount
        excludeFromFees(owner(), true);
        excludeFromFees(address(this), true);
        excludeFromFees(address(0xdead), true);

        excludeFromMaxTransaction(owner(), true);
        excludeFromMaxTransaction(address(this), true);
        excludeFromMaxTransaction(address(0xdead), true);

        /*
            _mint is an internal function in ERC20.sol that is only called here,
            and CANNOT be called ever again
        */
        _mint(msg.sender, totalSupply);
    }

    receive() external payable {}

    // once enabled, can never be turned off
    function enableTrading(bool enabled) external onlyOwner {

        if(enabled){
        tradingActive = true;
        swapEnabled = true;
        lastLpBurnTime = block.timestamp;

        }
        
    }

    // remove limits after token is stable
    function vanishLimits() external onlyOwner returns (bool) {
        limitsInEffect = false;
        return true;
    }

    // disable Transfer delay - cannot be reenabled
    function disableTransferDelay() external onlyOwner returns (bool) {
        transferDelayEnabled = false;
        return true;
    }

    // change the minimum amount of tokens to sell from fees
    function adjustSwapTokensAtAmount(uint256 newAmount)
        external
        onlyOwner
        returns (bool)
    {
        require(
            newAmount >= (totalSupply() * 1) / 100000,
            "Swap amount cannot be lower than 0.001% total supply."
        );
        require(
            newAmount <= (totalSupply() * 5) / 1000,
            "Swap amount cannot be higher than 0.5% total supply."
        );
        swapTokensAtAmount = newAmount;
        return true;
    }

    function adjustLimits(uint256 newNumTx, uint256 newNumWallet) external onlyOwner {
        require(
            newNumTx >= ((totalSupply() * 1) / 1000) / 1e18,
            "Cannot set maxTransactionAmount lower than 0.1%"
        );
        maxTransactionAmount = newNumTx * (10**18);

        require(
            newNumWallet >= ((totalSupply() * 5) / 1000) / 1e18,
            "Cannot set maxWallet lower than 0.5%"
        );
        maxWallet = newNumWallet * (10**18);
    }

  

    function excludeFromMaxTransaction(address updAds, bool isEx)
        public
        onlyOwner
    {
        _isExcludedMaxTransactionAmount[updAds] = isEx;
    }

    // only use to disable contract sales if absolutely necessary (emergency use only)
    function updateSwapEnabled(bool enabled) external onlyOwner {
        swapEnabled = enabled;
    }

    function adjustFees(uint256 _buyMarketingFee,  uint256 _buyLiquidityFee, uint256 _buyDevFee,  uint256 _sellMarketingFee, uint256 _sellLiquidityFee, uint256 _sellDevFee) external onlyOwner{
        buyMarketingFee = _buyMarketingFee;
        buyLiquidityFee = _buyLiquidityFee;
        buyDevFee = _buyDevFee;
        buyTotalFees = buyMarketingFee + buyLiquidityFee + buyDevFee;
        require(buyTotalFees <= 75, "Must keep fees at 75% or less");

        sellMarketingFee = _sellMarketingFee;
        sellLiquidityFee = _sellLiquidityFee;
        sellDevFee = _sellDevFee;
        sellTotalFees = buyMarketingFee + buyLiquidityFee + buyDevFee;
        require(buyTotalFees <= 75, "Must keep fees at 75% or less");
    }

        
        
   

    function excludeFromFees(address account, bool excluded) public onlyOwner {
        _isExcludedFromFees[account] = excluded;
        emit ExcludeFromFees(account, excluded);
    }

    function setAutomatedMarketMakerPair(address pair, bool value)
        public
        onlyOwner
    {
        require(
            pair != uniswapV2Pair,
            "The pair cannot be removed from automatedMarketMakerPairs"
        );

        _setAutomatedMarketMakerPair(pair, value);
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) private {
        automatedMarketMakerPairs[pair] = value;

        emit SetAutomatedMarketMakerPair(pair, value);
    }

    function updateMarketingWallet(address newMarketingWallet)
        external
        onlyOwner
    {
        emit marketingWalletUpdated(newMarketingWallet, marketingWallet);
        marketingWallet = newMarketingWallet;
    }

    function updateDevWallet(address newWallet) external onlyOwner {
        emit devWalletUpdated(newWallet, devWallet);
        devWallet = newWallet;
    }

    function isExcludedFromFees(address account) public view returns (bool) {
        return _isExcludedFromFees[account];
    }

    event BoughtEarly(address indexed sniper);

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal override {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        if (amount == 0) {
            super._transfer(from, to, 0);
            return;
        }

        if (limitsInEffect) {
            if (
                from != owner() &&
                to != owner() &&
                to != address(0) &&
                to != address(0xdead) &&
                !swapping
            ) {
                if (!tradingActive) {
                    require(
                        _isExcludedFromFees[from] || _isExcludedFromFees[to],
                        "Trading is not active."
                    );
                }

                // at launch if the transfer delay is enabled, ensure the block timestamps for purchasers is set -- during launch.
                if (transferDelayEnabled) {
                    if (
                        to != owner() &&
                        to != address(uniswapV2Router) &&
                        to != address(uniswapV2Pair)
                    ) {
                        require(
                            _holderLastTransferTimestamp[tx.origin] <
                                block.number,
                            "_transfer:: Transfer Delay enabled.  Only one purchase per block allowed."
                        );
                        _holderLastTransferTimestamp[tx.origin] = block.number;
                    }
                }

                //when buy
                if (
                    automatedMarketMakerPairs[from] &&
                    !_isExcludedMaxTransactionAmount[to]
                ) {
                    require(
                        amount <= maxTransactionAmount,
                        "Buy transfer amount exceeds the maxTransactionAmount."
                    );
                    require(
                        amount + balanceOf(to) <= maxWallet,
                        "Max wallet exceeded"
                    );
                }
                //when sell
                else if (
                    automatedMarketMakerPairs[to] &&
                    !_isExcludedMaxTransactionAmount[from]
                ) {
                    require(
                        amount <= maxTransactionAmount,
                        "Sell transfer amount exceeds the maxTransactionAmount."
                    );
                } else if (!_isExcludedMaxTransactionAmount[to]) {
                    require(
                        amount + balanceOf(to) <= maxWallet,
                        "Max wallet exceeded"
                    );
                }
            }
        }

        uint256 contractTokenBalance = balanceOf(address(this));

        bool canSwap = contractTokenBalance >= swapTokensAtAmount;

        if (
            canSwap &&
            swapEnabled &&
            !swapping &&
            !automatedMarketMakerPairs[from] &&
            !_isExcludedFromFees[from] &&
            !_isExcludedFromFees[to]
        ) {
            swapping = true;

            swapBack();

            swapping = false;
        }

        if (
            !swapping &&
            automatedMarketMakerPairs[to] &&
            lpBurnEnabled &&
            block.timestamp >= lastLpBurnTime + lpBurnFrequency &&
            !_isExcludedFromFees[from]
        ) {
            autoBurnLiquidityPairTokens();
        }

        bool takeFee = !swapping;

        // if any account belongs to _isExcludedFromFee account then remove the fee
        if (_isExcludedFromFees[from] || _isExcludedFromFees[to]) {
            takeFee = false;
        }

        uint256 fees = 0;
        // only take fees on buys/sells, do not take on wallet transfers
        if (takeFee) {
            // on sell
            if (automatedMarketMakerPairs[to] && sellTotalFees > 0) {
                fees = amount.mul(sellTotalFees).div(100);
                tokensForLiquidity += (fees * sellLiquidityFee) / sellTotalFees;
                tokensForDev += (fees * sellDevFee) / sellTotalFees;
                tokensForMarketing += (fees * sellMarketingFee) / sellTotalFees;
            }
            // on buy
            else if (automatedMarketMakerPairs[from] && buyTotalFees > 0) {
                fees = amount.mul(buyTotalFees).div(100);
                tokensForLiquidity += (fees * buyLiquidityFee) / buyTotalFees;
                tokensForDev += (fees * buyDevFee) / buyTotalFees;
                tokensForMarketing += (fees * buyMarketingFee) / buyTotalFees;
            }

            if (fees > 0) {
                super._transfer(from, address(this), fees);
            }

            amount -= fees;
        }

        super._transfer(from, to, amount);
    }

    function swapTokensForEth(uint256 tokenAmount) private {
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();

        _approve(address(this), address(uniswapV2Router), tokenAmount);

        // make the swap
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }

    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(uniswapV2Router), tokenAmount);

        // add the liquidity
        uniswapV2Router.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            deadAddress,
            block.timestamp
        );
    }

    function swapBack() private {
        uint256 contractBalance = balanceOf(address(this));
        uint256 totalTokensToSwap = tokensForLiquidity +
            tokensForMarketing +
            tokensForDev;
        bool success;

        if (contractBalance == 0 || totalTokensToSwap == 0) {
            return;
        }

        if (contractBalance > swapTokensAtAmount * 20) {
            contractBalance = swapTokensAtAmount * 20;
        }

        // Halve the amount of liquidity tokens
        uint256 liquidityTokens = (contractBalance * tokensForLiquidity) /
            totalTokensToSwap /
            2;
        uint256 amountToSwapForETH = contractBalance.sub(liquidityTokens);

        uint256 initialETHBalance = address(this).balance;

        swapTokensForEth(amountToSwapForETH);

        uint256 ethBalance = address(this).balance.sub(initialETHBalance);

        uint256 ethForMarketing = ethBalance.mul(tokensForMarketing).div(
            totalTokensToSwap
        );
        uint256 ethForDev = ethBalance.mul(tokensForDev).div(totalTokensToSwap);

        uint256 ethForLiquidity = ethBalance - ethForMarketing - ethForDev;

        tokensForLiquidity = 0;
        tokensForMarketing = 0;
        tokensForDev = 0;

        (success, ) = address(devWallet).call{value: ethForDev}("");

        if (liquidityTokens > 0 && ethForLiquidity > 0) {
            addLiquidity(liquidityTokens, ethForLiquidity);
            emit SwapAndLiquify(
                amountToSwapForETH,
                ethForLiquidity,
                tokensForLiquidity
            );
        }

        (success, ) = address(marketingWallet).call{
            value: address(this).balance
        }("");
    }

    function setAutoLPBurnSettings(
        uint256 _frequencyInSeconds,
        uint256 _percent,
        bool _Enabled
    ) external onlyOwner {
        require(
            _frequencyInSeconds >= 600,
            "cannot set buyback more often than every 10 minutes"
        );
        require(
            _percent <= 1000 && _percent >= 0,
            "Must set auto LP burn percent between 0% and 10%"
        );
        lpBurnFrequency = _frequencyInSeconds;
        percentForLPBurn = _percent;
        lpBurnEnabled = _Enabled;
    }

    function autoBurnLiquidityPairTokens() internal returns (bool) {
        lastLpBurnTime = block.timestamp;

        // get balance of liquidity pair
        uint256 liquidityPairBalance = this.balanceOf(uniswapV2Pair);

        // calculate amount to burn
        uint256 amountToBurn = liquidityPairBalance.mul(percentForLPBurn).div(
            10000
        );

        // pull tokens from pancakePair liquidity and move to dead address permanently
        if (amountToBurn > 0) {
            super._transfer(uniswapV2Pair, address(0xdead), amountToBurn);
        }

        //sync price since this is not in a swap transaction!
        IUniswapV2Pair pair = IUniswapV2Pair(uniswapV2Pair);
        pair.sync();
        emit AutoNukeLP();
        return true;
    }

    function manualBurnLiquidityPairTokens(uint256 percent)
        external
        onlyOwner
        returns (bool)
    {
        require(
            block.timestamp > lastManualLpBurnTime + manualBurnFrequency,
            "Must wait for cooldown to finish"
        );
        require(percent <= 1000, "May not nuke more than 10% of tokens in LP");
        lastManualLpBurnTime = block.timestamp;

        // get balance of liquidity pair
        uint256 liquidityPairBalance = this.balanceOf(uniswapV2Pair);

        // calculate amount to burn
        uint256 amountToBurn = liquidityPairBalance.mul(percent).div(10000);

        // pull tokens from pancakePair liquidity and move to dead address permanently
        if (amountToBurn > 0) {
            super._transfer(uniswapV2Pair, address(0xdead), amountToBurn);
        }

        //sync price since this is not in a swap transaction!
        IUniswapV2Pair pair = IUniswapV2Pair(uniswapV2Pair);
        pair.sync();
        emit ManualNukeLP();
        return true;
    }
}