// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
import "./SmartWalletStorage.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/EnumerableSet.sol";
contract SmartWalletProxy is SmartWalletStorage {
    using Address for address;
    using EnumerableSet for EnumerableSet.AddressSet;
    event ImplementationUpdated(address indexed implementation);
    constructor(
        address _admin,
        address _implementation,
        address[] memory _supportedPlatformWallets,
        address[] memory _supportedSwaps,
        address[] memory _supportedLendings
    ) SmartWalletStorage(_admin) {
        _setImplementation(_implementation);
        for (uint256 i = 0; i < _supportedPlatformWallets.length; i++) {
            supportedPlatformWallets.add(_supportedPlatformWallets[i]);
        }
        for (uint256 i = 0; i < _supportedSwaps.length; i++) {
            supportedSwaps.add(_supportedSwaps[i]);
        }
        for (uint256 i = 0; i < _supportedLendings.length; i++) {
            supportedLendings.add(_supportedLendings[i]);
        }
    }
    receive() external payable {}
    /**
     * @dev Delegates execution to an implementation contract.
     * It returns to the external caller whatever the implementation returns
     * or forwards reverts.
     */
    fallback() external payable {
        (bool success, ) = implementation().delegatecall(msg.data);
        assembly {
            let free_mem_ptr := mload(0x40)
            returndatacopy(free_mem_ptr, 0, returndatasize())
            switch success
                case 0 {
                    revert(free_mem_ptr, returndatasize())
                }
                default {
                    return(free_mem_ptr, returndatasize())
                }
        }
    }
    function implementation() public view returns (address impl) {
        bytes32 slot = IMPLEMENTATION;
        assembly {
            impl := sload(slot)
        }
    }
    function _setImplementation(address _implementation) internal {
        require(_implementation.isContract(), "non-contract address");
        bytes32 slot = IMPLEMENTATION;
        assembly {
            sstore(slot, _implementation)
        }
    }
    function updateNewImplementation(address _implementation) external onlyAdmin {
        _setImplementation(_implementation);
        emit ImplementationUpdated(_implementation);
    }
    function updateSupportedSwaps(address[] calldata addresses, bool isSupported)
        external onlyAdmin
    {
        for (uint256 i = 0; i < addresses.length; i++) {
            if (isSupported) {
                supportedSwaps.add(addresses[i]);
            } else {
                supportedSwaps.remove(addresses[i]);
            }
        }
    }
    function getAllSupportedSwaps() external view returns (address[] memory addresses) {
        uint256 length = supportedSwaps.length();
        addresses = new address[](length);
        for (uint256 i = 0; i < length; i++) {
            addresses[i] = supportedSwaps.at(i);
        }
    }
    function updateSupportedLendings(address[] calldata addresses, bool isSupported)
        external onlyAdmin
    {
        for (uint256 i = 0; i < addresses.length; i++) {
            if (isSupported) {
                supportedLendings.add(addresses[i]);
            } else {
                supportedLendings.remove(addresses[i]);
            }
        }
    }
    function getAllSupportedLendings() external view returns (address[] memory addresses) {
        uint256 length = supportedLendings.length();
        addresses = new address[](length);
        for (uint256 i = 0; i < length; i++) {
            addresses[i] = supportedLendings.at(i);
        }
    }
    function updateSupportedPlatformWallets(address[] calldata addresses, bool isSupported)
        external onlyAdmin
    {
        for (uint256 i = 0; i < addresses.length; i++) {
            if (isSupported) {
                supportedPlatformWallets.add(addresses[i]);
            } else {
                supportedPlatformWallets.remove(addresses[i]);
            }
        }
    }
    function getAllSupportedPlatformWallets() external view returns (address[] memory addresses) {
        uint256 length = supportedPlatformWallets.length();
        addresses = new address[](length);
        for (uint256 i = 0; i < length; i++) {
            addresses[i] = supportedPlatformWallets.at(i);
        }
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
import "@kyber.network/utils-sc/contracts/IERC20Ext.sol";
import "@kyber.network/utils-sc/contracts/Utils.sol";
import "@kyber.network/utils-sc/contracts/Withdrawable.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/EnumerableSet.sol";
contract SmartWalletStorage is Utils, Withdrawable, ReentrancyGuard {
    uint256 internal constant MAX_AMOUNT = type(uint256).max;
    mapping(address => mapping(IERC20Ext => uint256)) public platformWalletFees;
    EnumerableSet.AddressSet internal supportedPlatformWallets;
    
    EnumerableSet.AddressSet internal supportedSwaps;
    EnumerableSet.AddressSet internal supportedLendings;
    // [EIP-1967] bytes32(uint256(keccak256("SmartWalletImplementation")) - 1)
    bytes32 internal constant IMPLEMENTATION =
        0x7cf58d76330f82325c2a503c72b55abca3eb533fadde43d95e3c0cceb1583e99;
    constructor(address _admin) Withdrawable(_admin) {}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.
    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];
        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.
            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;
            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
            bytes32 lastvalue = set._values[lastIndex];
            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based
            // Delete the slot where the moved value was stored
            set._values.pop();
            // Delete the index for the deleted slot
            delete set._indexes[value];
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }
    // Bytes32Set
    struct Bytes32Set {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }
    // AddressSet
    struct AddressSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }
    // UintSet
    struct UintSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
/**
 * @dev Interface extending ERC20 standard to include decimals() as
 *      it is optional in the OpenZeppelin IERC20 interface.
 */
interface IERC20Ext is IERC20 {
    /**
     * @dev This function is required as Kyber requires to interact
     *      with token.decimals() with many of its operations.
     */
    function decimals() external view returns (uint8 digits);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./IERC20Ext.sol";
/**
 * @title Kyber utility file
 * mostly shared constants and rate calculation helpers
 * inherited by most of kyber contracts.
 * previous utils implementations are for previous solidity versions.
 */
abstract contract Utils {
    // Declared constants below to be used in tandem with
    // getDecimalsConstant(), for gas optimization purposes
    // which return decimals from a constant list of popular
    // tokens.
    IERC20Ext internal constant ETH_TOKEN_ADDRESS = IERC20Ext(
        0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE
    );
    IERC20Ext internal constant USDT_TOKEN_ADDRESS = IERC20Ext(
        0xdAC17F958D2ee523a2206206994597C13D831ec7
    );
    IERC20Ext internal constant DAI_TOKEN_ADDRESS = IERC20Ext(
        0x6B175474E89094C44Da98b954EedeAC495271d0F
    );
    IERC20Ext internal constant USDC_TOKEN_ADDRESS = IERC20Ext(
        0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48
    );
    IERC20Ext internal constant WBTC_TOKEN_ADDRESS = IERC20Ext(
        0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599
    );
    IERC20Ext internal constant KNC_TOKEN_ADDRESS = IERC20Ext(
        0xdd974D5C2e2928deA5F71b9825b8b646686BD200
    );
    uint256 public constant BPS = 10000; // Basic Price Steps. 1 step = 0.01%
    uint256 internal constant PRECISION = (10**18);
    uint256 internal constant MAX_QTY = (10**28); // 10B tokens
    uint256 internal constant MAX_RATE = (PRECISION * 10**7); // up to 10M tokens per eth
    uint256 internal constant MAX_DECIMALS = 18;
    uint256 internal constant ETH_DECIMALS = 18;
    uint256 internal constant MAX_ALLOWANCE = uint256(-1); // token.approve inifinite
    mapping(IERC20Ext => uint256) internal decimals;
    /// @dev Sets the decimals of a token to storage if not already set, and returns
    ///      the decimals value of the token. Prefer using this function over
    ///      getDecimals(), to avoid forgetting to set decimals in local storage.
    /// @param token The token type
    /// @return tokenDecimals The decimals of the token
    function getSetDecimals(IERC20Ext token) internal returns (uint256 tokenDecimals) {
        tokenDecimals = getDecimalsConstant(token);
        if (tokenDecimals > 0) return tokenDecimals;
        tokenDecimals = decimals[token];
        if (tokenDecimals == 0) {
            tokenDecimals = token.decimals();
            decimals[token] = tokenDecimals;
        }
    }
    /// @dev Get the balance of a user
    /// @param token The token type
    /// @param user The user's address
    /// @return The balance
    function getBalance(IERC20Ext token, address user) internal view returns (uint256) {
        if (token == ETH_TOKEN_ADDRESS) {
            return user.balance;
        } else {
            return token.balanceOf(user);
        }
    }
    /// @dev Get the decimals of a token, read from the constant list, storage,
    ///      or from token.decimals(). Prefer using getSetDecimals when possible.
    /// @param token The token type
    /// @return tokenDecimals The decimals of the token
    function getDecimals(IERC20Ext token) internal view returns (uint256 tokenDecimals) {
        // return token decimals if has constant value
        tokenDecimals = getDecimalsConstant(token);
        if (tokenDecimals > 0) return tokenDecimals;
        // handle case where token decimals is not a declared decimal constant
        tokenDecimals = decimals[token];
        // moreover, very possible that old tokens have decimals 0
        // these tokens will just have higher gas fees.
        return (tokenDecimals > 0) ? tokenDecimals : token.decimals();
    }
    function calcDestAmount(
        IERC20Ext src,
        IERC20Ext dest,
        uint256 srcAmount,
        uint256 rate
    ) internal view returns (uint256) {
        return calcDstQty(srcAmount, getDecimals(src), getDecimals(dest), rate);
    }
    function calcSrcAmount(
        IERC20Ext src,
        IERC20Ext dest,
        uint256 destAmount,
        uint256 rate
    ) internal view returns (uint256) {
        return calcSrcQty(destAmount, getDecimals(src), getDecimals(dest), rate);
    }
    function calcDstQty(
        uint256 srcQty,
        uint256 srcDecimals,
        uint256 dstDecimals,
        uint256 rate
    ) internal pure returns (uint256) {
        require(srcQty <= MAX_QTY, "srcQty > MAX_QTY");
        require(rate <= MAX_RATE, "rate > MAX_RATE");
        if (dstDecimals >= srcDecimals) {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            return (srcQty * rate * (10**(dstDecimals - srcDecimals))) / PRECISION;
        } else {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            return (srcQty * rate) / (PRECISION * (10**(srcDecimals - dstDecimals)));
        }
    }
    function calcSrcQty(
        uint256 dstQty,
        uint256 srcDecimals,
        uint256 dstDecimals,
        uint256 rate
    ) internal pure returns (uint256) {
        require(dstQty <= MAX_QTY, "dstQty > MAX_QTY");
        require(rate <= MAX_RATE, "rate > MAX_RATE");
        //source quantity is rounded up. to avoid dest quantity being too low.
        uint256 numerator;
        uint256 denominator;
        if (srcDecimals >= dstDecimals) {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            numerator = (PRECISION * dstQty * (10**(srcDecimals - dstDecimals)));
            denominator = rate;
        } else {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            numerator = (PRECISION * dstQty);
            denominator = (rate * (10**(dstDecimals - srcDecimals)));
        }
        return (numerator + denominator - 1) / denominator; //avoid rounding down errors
    }
    function calcRateFromQty(
        uint256 srcAmount,
        uint256 destAmount,
        uint256 srcDecimals,
        uint256 dstDecimals
    ) internal pure returns (uint256) {
        require(srcAmount <= MAX_QTY, "srcAmount > MAX_QTY");
        require(destAmount <= MAX_QTY, "destAmount > MAX_QTY");
        if (dstDecimals >= srcDecimals) {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            return ((destAmount * PRECISION) / ((10**(dstDecimals - srcDecimals)) * srcAmount));
        } else {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            return ((destAmount * PRECISION * (10**(srcDecimals - dstDecimals))) / srcAmount);
        }
    }
    /// @dev save storage access by declaring token decimal constants
    /// @param token The token type
    /// @return token decimals
    function getDecimalsConstant(IERC20Ext token) internal pure returns (uint256) {
        if (token == ETH_TOKEN_ADDRESS) {
            return ETH_DECIMALS;
        } else if (token == USDT_TOKEN_ADDRESS) {
            return 6;
        } else if (token == DAI_TOKEN_ADDRESS) {
            return 18;
        } else if (token == USDC_TOKEN_ADDRESS) {
            return 6;
        } else if (token == WBTC_TOKEN_ADDRESS) {
            return 8;
        } else if (token == KNC_TOKEN_ADDRESS) {
            return 18;
        } else {
            return 0;
        }
    }
    function minOf(uint256 x, uint256 y) internal pure returns (uint256) {
        return x > y ? y : x;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./IERC20Ext.sol";
import "./PermissionAdmin.sol";
abstract contract Withdrawable is PermissionAdmin {
    using SafeERC20 for IERC20Ext;
    event TokenWithdraw(IERC20Ext token, uint256 amount, address sendTo);
    event EtherWithdraw(uint256 amount, address sendTo);
    constructor(address _admin) PermissionAdmin(_admin) {}
    /**
     * @dev Withdraw all IERC20Ext compatible tokens
     * @param token IERC20Ext The address of the token contract
     */
    function withdrawToken(
        IERC20Ext token,
        uint256 amount,
        address sendTo
    ) external onlyAdmin {
        token.safeTransfer(sendTo, amount);
        emit TokenWithdraw(token, amount, sendTo);
    }
    /**
     * @dev Withdraw Ethers
     */
    function withdrawEther(uint256 amount, address payable sendTo) external onlyAdmin {
        (bool success, ) = sendTo.call{value: amount}("");
        require(success, "withdraw failed");
        emit EtherWithdraw(amount, sendTo);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;
    uint256 private _status;
    constructor () internal {
        _status = _NOT_ENTERED;
    }
    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    using Address for address;
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
abstract contract PermissionAdmin {
    address public admin;
    address public pendingAdmin;
    event AdminClaimed(address newAdmin, address previousAdmin);
    event TransferAdminPending(address pendingAdmin);
    constructor(address _admin) {
        require(_admin != address(0), "admin 0");
        admin = _admin;
    }
    modifier onlyAdmin() {
        require(msg.sender == admin, "only admin");
        _;
    }
    /**
     * @dev Allows the current admin to set the pendingAdmin address.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdmin(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0), "new admin 0");
        emit TransferAdminPending(newAdmin);
        pendingAdmin = newAdmin;
    }
    /**
     * @dev Allows the current admin to set the admin in one tx. Useful initial deployment.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdminQuickly(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0), "admin 0");
        emit TransferAdminPending(newAdmin);
        emit AdminClaimed(newAdmin, admin);
        admin = newAdmin;
    }
    /**
     * @dev Allows the pendingAdmin address to finalize the change admin process.
     */
    function claimAdmin() public {
        require(pendingAdmin == msg.sender, "not pending");
        emit AdminClaimed(pendingAdmin, admin);
        admin = pendingAdmin;
        pendingAdmin = address(0);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
pragma experimental ABIEncoderV2;
import "./BaseSwap.sol";
import "../libraries/BytesLib.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/EnumerableSet.sol";
import "@kyber.network/utils-sc/contracts/IERC20Ext.sol";
import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
import "../libraries/UniswapV2Library.sol";
/// General swap for uniswap and its clones
contract UniSwap is BaseSwap {
    using SafeERC20 for IERC20Ext;
    using SafeMath for uint256;
    using Address for address;
    using EnumerableSet for EnumerableSet.AddressSet;
    using BytesLib for bytes;
    EnumerableSet.AddressSet private uniRouters;
    address public wEth;
    mapping(address => bytes4) public customSwapFromEth;
    mapping(address => bytes4) public customSwapToEth;
    event UpdatedUniRouters(IUniswapV2Router02[] routers, bool isSupported);
    constructor(
        address _admin,
        IUniswapV2Router02[] memory routers,
        address _weth
    ) BaseSwap(_admin) {
        for (uint256 i = 0; i < routers.length; i++) {
            uniRouters.add(address(routers[i]));
        }
        wEth = _weth;
    }
    function getAllUniRouters() external view returns (address[] memory addresses) {
        uint256 length = uniRouters.length();
        addresses = new address[](length);
        for (uint256 i = 0; i < length; i++) {
            addresses[i] = uniRouters.at(i);
        }
    }
    function updateCustomSwapSelector(
        address _router,
        bytes4 _swapFromEth,
        bytes4 _swapToEth
    ) external onlyAdmin {
        customSwapFromEth[_router] = _swapFromEth;
        customSwapToEth[_router] = _swapToEth;
    }
    function updateUniRouters(IUniswapV2Router02[] calldata routers, bool isSupported)
        external
        onlyAdmin
    {
        for (uint256 i = 0; i < routers.length; i++) {
            if (isSupported) {
                uniRouters.add(address(routers[i]));
            } else {
                uniRouters.remove(address(routers[i]));
            }
        }
        emit UpdatedUniRouters(routers, isSupported);
    }
    /// @dev get expected return and conversion rate if using a Uni router
    function getExpectedReturn(GetExpectedReturnParams calldata params)
        external
        view
        override
        onlyProxyContract
        returns (uint256 destAmount)
    {
        address router = parseExtraArgs(params.extraArgs);
        uint256[] memory amounts = IUniswapV2Router02(router).getAmountsOut(
            params.srcAmount,
            params.tradePath
        );
        destAmount = amounts[params.tradePath.length - 1];
    }
    /// @dev get expected return and conversion rate if using a Uni router
    function getExpectedReturnWithImpact(GetExpectedReturnParams calldata params)
        external
        view
        override
        onlyProxyContract
        returns (uint256 destAmount, uint256 priceImpact)
    {
        address router = parseExtraArgs(params.extraArgs);
        uint256[] memory amounts = IUniswapV2Router02(router).getAmountsOut(
            params.srcAmount,
            params.tradePath
        );
        destAmount = amounts[params.tradePath.length - 1];
        priceImpact = getPriceImpact(
            params.srcAmount,
            destAmount,
            IUniswapV2Router02(router).factory(),
            params.tradePath
        );
    }
    function getExpectedIn(GetExpectedInParams calldata params)
        external
        view
        override
        onlyProxyContract
        returns (uint256 srcAmount)
    {
        address router = parseExtraArgs(params.extraArgs);
        uint256[] memory amounts = IUniswapV2Router02(router).getAmountsIn(
            params.destAmount,
            params.tradePath
        );
        srcAmount = amounts[0];
    }
    function getExpectedInWithImpact(GetExpectedInParams calldata params)
        external
        view
        override
        onlyProxyContract
        returns (uint256 srcAmount, uint256 priceImpact)
    {
        address router = parseExtraArgs(params.extraArgs);
        uint256[] memory amounts = IUniswapV2Router02(router).getAmountsIn(
            params.destAmount,
            params.tradePath
        );
        srcAmount = amounts[0];
        priceImpact = getPriceImpact(
            srcAmount,
            params.destAmount,
            IUniswapV2Router02(router).factory(),
            params.tradePath
        );
    }
    function getPriceImpact(
        uint256 srcAmount,
        uint256 destAmount,
        address factory,
        address[] memory path
    ) private view returns (uint256 priceImpact) {
        uint256 quote = srcAmount;
        for (uint256 i; i < path.length - 1; i++) {
            (uint256 reserveIn, uint256 reserveOut) = UniswapV2Library.getReserves(
                factory,
                path[i],
                path[i + 1]
            );
            quote = UniswapV2Library.quote(quote.mul(997).div(1000), reserveIn, reserveOut);
        }
        if (quote <= destAmount) {
            priceImpact = 0;
        } else {
            priceImpact = quote.sub(destAmount).mul(BPS).div(quote);
        }
    }
    /// @dev swap token via a supported UniSwap router
    /// @notice for some tokens that are paying fee, for example: DGX
    /// contract will trade with received src token amount (after minus fee)
    /// for UniSwap, fee will be taken in src token
    function swap(SwapParams calldata params)
        external
        payable
        override
        onlyProxyContract
        returns (uint256 destAmount)
    {
        require(params.tradePath.length >= 2, "invalid tradePath");
        address router = parseExtraArgs(params.extraArgs);
        safeApproveAllowance(router, IERC20Ext(params.tradePath[0]));
        uint256 tradeLen = params.tradePath.length;
        IERC20Ext actualSrc = IERC20Ext(params.tradePath[0]);
        IERC20Ext actualDest = IERC20Ext(params.tradePath[tradeLen - 1]);
        // convert eth/bnb -> weth/wbnb address to trade on Uni
        address[] memory convertedTradePath = params.tradePath;
        if (convertedTradePath[0] == address(ETH_TOKEN_ADDRESS)) {
            convertedTradePath[0] = wEth;
        }
        if (convertedTradePath[tradeLen - 1] == address(ETH_TOKEN_ADDRESS)) {
            convertedTradePath[tradeLen - 1] = wEth;
        }
        uint256 destBalanceBefore = getBalance(actualDest, params.recipient);
        if (actualSrc == ETH_TOKEN_ADDRESS) {
            // swap eth/bnb -> token
            if (customSwapFromEth[address(router)] != "") {
                (bool success, ) = router.call{value: params.srcAmount}(
                    abi.encodeWithSelector(
                        customSwapFromEth[address(router)],
                        params.minDestAmount,
                        convertedTradePath,
                        params.recipient,
                        MAX_AMOUNT
                    )
                );
                require(success, "swapFromEth: failed");
            } else {
                IUniswapV2Router02(router).swapExactETHForTokensSupportingFeeOnTransferTokens{
                    value: params.srcAmount
                }(params.minDestAmount, convertedTradePath, params.recipient, MAX_AMOUNT);
            }
        } else {
            if (actualDest == ETH_TOKEN_ADDRESS) {
                // swap token -> eth/bnb
                if (customSwapToEth[address(router)] != "") {
                    (bool success, ) = router.call(
                        abi.encodeWithSelector(
                            customSwapToEth[address(router)],
                            params.srcAmount,
                            params.minDestAmount,
                            convertedTradePath,
                            params.recipient,
                            MAX_AMOUNT
                        )
                    );
                    require(success, "swapToEth: failed");
                } else {
                    IUniswapV2Router02(router).swapExactTokensForETHSupportingFeeOnTransferTokens(
                        params.srcAmount,
                        params.minDestAmount,
                        convertedTradePath,
                        params.recipient,
                        MAX_AMOUNT
                    );
                }
            } else {
                // swap token -> token
                IUniswapV2Router02(router).swapExactTokensForTokensSupportingFeeOnTransferTokens(
                    params.srcAmount,
                    params.minDestAmount,
                    convertedTradePath,
                    params.recipient,
                    MAX_AMOUNT
                );
            }
        }
        destAmount = getBalance(actualDest, params.recipient).sub(destBalanceBefore);
    }
    /// @param extraArgs expecting <[20B] address router>
    function parseExtraArgs(bytes calldata extraArgs) internal view returns (address router) {
        require(extraArgs.length == 20, "invalid args");
        router = extraArgs.toAddress(0);
        require(router != address(0), "invalid address");
        require(uniRouters.contains(router), "unsupported router");
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
pragma abicoder v2;
import "@kyber.network/utils-sc/contracts/Withdrawable.sol";
import "@kyber.network/utils-sc/contracts/Utils.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./ISwap.sol";
abstract contract BaseSwap is ISwap, Withdrawable, Utils {
    using SafeERC20 for IERC20Ext;
    using SafeMath for uint256;
    uint256 internal constant MAX_AMOUNT = type(uint256).max;
    address public proxyContract;
    event UpdatedproxyContract(address indexed _oldProxyImpl, address indexed _newProxyImpl);
    modifier onlyProxyContract() {
        require(msg.sender == proxyContract, "only swap impl");
        _;
    }
    constructor(address _admin) Withdrawable(_admin) {}
    receive() external payable {}
    function updateProxyContract(address _proxyContract) external onlyAdmin {
        require(_proxyContract != address(0), "invalid swap impl");
        emit UpdatedproxyContract(proxyContract, _proxyContract);
        proxyContract = _proxyContract;
    }
    // Swap contracts don't keep funds. It's safe to set the max allowance
    function safeApproveAllowance(address spender, IERC20Ext token) internal {
        if (token != ETH_TOKEN_ADDRESS && token.allowance(address(this), spender) == 0) {
            token.safeApprove(spender, MAX_ALLOWANCE);
        }
    }
}
pragma solidity 0.7.6;
library BytesLib {
    function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
        require(_start + 20 >= _start, "toAddress_overflow");
        require(_bytes.length >= _start + 20, "toAddress_outOfBounds");
        address tempAddress;
        assembly {
            tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
        }
        return tempAddress;
    }
    function toUint24(bytes memory _bytes, uint256 _start) internal pure returns (uint24) {
        require(_start + 3 >= _start, "toUint24_overflow");
        require(_bytes.length >= _start + 3, "toUint24_outOfBounds");
        uint24 tempUint;
        assembly {
            tempUint := mload(add(add(_bytes, 0x3), _start))
        }
        return tempUint;
    }
    function toUint256(bytes memory _bytes, uint256 _start) internal pure returns (uint256) {
        require(_start + 32 >= _start, "toUint256_overflow");
        require(_bytes.length >= _start + 32, "toUint256_outOfBounds");
        uint256 tempUint;
        assembly {
            tempUint := mload(add(add(_bytes, 0x20), _start))
        }
        return tempUint;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    using Address for address;
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.
    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];
        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.
            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;
            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
            bytes32 lastvalue = set._values[lastIndex];
            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based
            // Delete the slot where the moved value was stored
            set._values.pop();
            // Delete the index for the deleted slot
            delete set._indexes[value];
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }
    // Bytes32Set
    struct Bytes32Set {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }
    // AddressSet
    struct AddressSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }
    // UintSet
    struct UintSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
/**
 * @dev Interface extending ERC20 standard to include decimals() as
 *      it is optional in the OpenZeppelin IERC20 interface.
 */
interface IERC20Ext is IERC20 {
    /**
     * @dev This function is required as Kyber requires to interact
     *      with token.decimals() with many of its operations.
     */
    function decimals() external view returns (uint8 digits);
}
pragma solidity >=0.6.2;
import './IUniswapV2Router01.sol';
interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}
pragma solidity >=0.5.0;
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
library UniswapV2Library {
    using SafeMath for uint256;
    // returns sorted token addresses, used to handle return values from pairs sorted in this order
    function sortTokens(address tokenA, address tokenB)
        internal
        pure
        returns (address token0, address token1)
    {
        require(tokenA != tokenB, "UniswapV2Library: IDENTICAL_ADDRESSES");
        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), "UniswapV2Library: ZERO_ADDRESS");
    }
    // calculates the CREATE2 address for a pair without making any external calls
    function pairFor(
        address factory,
        address tokenA,
        address tokenB
    ) internal view returns (address pair) {
        return IUniswapV2Factory(factory).getPair(tokenA, tokenB);
        /*
        (address token0, address token1) = sortTokens(tokenA, tokenB);
        pair = address(uint(keccak256(abi.encodePacked(
                hex'ff',
                factory,
                keccak256(abi.encodePacked(token0, token1)),
                hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
            ))));
           */
    }
    // fetches and sorts the reserves for a pair
    function getReserves(
        address factory,
        address tokenA,
        address tokenB
    ) internal view returns (uint256 reserveA, uint256 reserveB) {
        (address token0, ) = sortTokens(tokenA, tokenB);
        (uint256 reserve0, uint256 reserve1, ) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB))
        .getReserves();
        (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
    }
    // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
    function quote(
        uint256 amountA,
        uint256 reserveA,
        uint256 reserveB
    ) internal pure returns (uint256 amountB) {
        require(amountA > 0, "UniswapV2Library: INSUFFICIENT_AMOUNT");
        require(reserveA > 0 && reserveB > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");
        amountB = amountA.mul(reserveB) / reserveA;
    }
    // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
    function getAmountOut(
        uint256 amountIn,
        uint256 reserveIn,
        uint256 reserveOut
    ) internal pure returns (uint256 amountOut) {
        require(amountIn > 0, "UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT");
        require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");
        uint256 amountInWithFee = amountIn.mul(997);
        uint256 numerator = amountInWithFee.mul(reserveOut);
        uint256 denominator = reserveIn.mul(1000).add(amountInWithFee);
        amountOut = numerator / denominator;
    }
    // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
    function getAmountIn(
        uint256 amountOut,
        uint256 reserveIn,
        uint256 reserveOut
    ) internal pure returns (uint256 amountIn) {
        require(amountOut > 0, "UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT");
        require(reserveIn > 0 && reserveOut > 0, "UniswapV2Library: INSUFFICIENT_LIQUIDITY");
        uint256 numerator = reserveIn.mul(amountOut).mul(1000);
        uint256 denominator = reserveOut.sub(amountOut).mul(997);
        amountIn = (numerator / denominator).add(1);
    }
    // performs chained getAmountOut calculations on any number of pairs
    function getAmountsOut(
        address factory,
        uint256 amountIn,
        address[] memory path
    ) internal view returns (uint256[] memory amounts) {
        require(path.length >= 2, "UniswapV2Library: INVALID_PATH");
        amounts = new uint256[](path.length);
        amounts[0] = amountIn;
        for (uint256 i; i < path.length - 1; i++) {
            (uint256 reserveIn, uint256 reserveOut) = getReserves(factory, path[i], path[i + 1]);
            amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
        }
    }
    // performs chained getAmountIn calculations on any number of pairs
    function getAmountsIn(
        address factory,
        uint256 amountOut,
        address[] memory path
    ) internal view returns (uint256[] memory amounts) {
        require(path.length >= 2, "UniswapV2Library: INVALID_PATH");
        amounts = new uint256[](path.length);
        amounts[amounts.length - 1] = amountOut;
        for (uint256 i = path.length - 1; i > 0; i--) {
            (uint256 reserveIn, uint256 reserveOut) = getReserves(factory, path[i - 1], path[i]);
            amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./IERC20Ext.sol";
import "./PermissionAdmin.sol";
abstract contract Withdrawable is PermissionAdmin {
    using SafeERC20 for IERC20Ext;
    event TokenWithdraw(IERC20Ext token, uint256 amount, address sendTo);
    event EtherWithdraw(uint256 amount, address sendTo);
    constructor(address _admin) PermissionAdmin(_admin) {}
    /**
     * @dev Withdraw all IERC20Ext compatible tokens
     * @param token IERC20Ext The address of the token contract
     */
    function withdrawToken(
        IERC20Ext token,
        uint256 amount,
        address sendTo
    ) external onlyAdmin {
        token.safeTransfer(sendTo, amount);
        emit TokenWithdraw(token, amount, sendTo);
    }
    /**
     * @dev Withdraw Ethers
     */
    function withdrawEther(uint256 amount, address payable sendTo) external onlyAdmin {
        (bool success, ) = sendTo.call{value: amount}("");
        require(success, "withdraw failed");
        emit EtherWithdraw(amount, sendTo);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./IERC20Ext.sol";
/**
 * @title Kyber utility file
 * mostly shared constants and rate calculation helpers
 * inherited by most of kyber contracts.
 * previous utils implementations are for previous solidity versions.
 */
abstract contract Utils {
    // Declared constants below to be used in tandem with
    // getDecimalsConstant(), for gas optimization purposes
    // which return decimals from a constant list of popular
    // tokens.
    IERC20Ext internal constant ETH_TOKEN_ADDRESS = IERC20Ext(
        0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE
    );
    IERC20Ext internal constant USDT_TOKEN_ADDRESS = IERC20Ext(
        0xdAC17F958D2ee523a2206206994597C13D831ec7
    );
    IERC20Ext internal constant DAI_TOKEN_ADDRESS = IERC20Ext(
        0x6B175474E89094C44Da98b954EedeAC495271d0F
    );
    IERC20Ext internal constant USDC_TOKEN_ADDRESS = IERC20Ext(
        0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48
    );
    IERC20Ext internal constant WBTC_TOKEN_ADDRESS = IERC20Ext(
        0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599
    );
    IERC20Ext internal constant KNC_TOKEN_ADDRESS = IERC20Ext(
        0xdd974D5C2e2928deA5F71b9825b8b646686BD200
    );
    uint256 public constant BPS = 10000; // Basic Price Steps. 1 step = 0.01%
    uint256 internal constant PRECISION = (10**18);
    uint256 internal constant MAX_QTY = (10**28); // 10B tokens
    uint256 internal constant MAX_RATE = (PRECISION * 10**7); // up to 10M tokens per eth
    uint256 internal constant MAX_DECIMALS = 18;
    uint256 internal constant ETH_DECIMALS = 18;
    uint256 internal constant MAX_ALLOWANCE = uint256(-1); // token.approve inifinite
    mapping(IERC20Ext => uint256) internal decimals;
    /// @dev Sets the decimals of a token to storage if not already set, and returns
    ///      the decimals value of the token. Prefer using this function over
    ///      getDecimals(), to avoid forgetting to set decimals in local storage.
    /// @param token The token type
    /// @return tokenDecimals The decimals of the token
    function getSetDecimals(IERC20Ext token) internal returns (uint256 tokenDecimals) {
        tokenDecimals = getDecimalsConstant(token);
        if (tokenDecimals > 0) return tokenDecimals;
        tokenDecimals = decimals[token];
        if (tokenDecimals == 0) {
            tokenDecimals = token.decimals();
            decimals[token] = tokenDecimals;
        }
    }
    /// @dev Get the balance of a user
    /// @param token The token type
    /// @param user The user's address
    /// @return The balance
    function getBalance(IERC20Ext token, address user) internal view returns (uint256) {
        if (token == ETH_TOKEN_ADDRESS) {
            return user.balance;
        } else {
            return token.balanceOf(user);
        }
    }
    /// @dev Get the decimals of a token, read from the constant list, storage,
    ///      or from token.decimals(). Prefer using getSetDecimals when possible.
    /// @param token The token type
    /// @return tokenDecimals The decimals of the token
    function getDecimals(IERC20Ext token) internal view returns (uint256 tokenDecimals) {
        // return token decimals if has constant value
        tokenDecimals = getDecimalsConstant(token);
        if (tokenDecimals > 0) return tokenDecimals;
        // handle case where token decimals is not a declared decimal constant
        tokenDecimals = decimals[token];
        // moreover, very possible that old tokens have decimals 0
        // these tokens will just have higher gas fees.
        return (tokenDecimals > 0) ? tokenDecimals : token.decimals();
    }
    function calcDestAmount(
        IERC20Ext src,
        IERC20Ext dest,
        uint256 srcAmount,
        uint256 rate
    ) internal view returns (uint256) {
        return calcDstQty(srcAmount, getDecimals(src), getDecimals(dest), rate);
    }
    function calcSrcAmount(
        IERC20Ext src,
        IERC20Ext dest,
        uint256 destAmount,
        uint256 rate
    ) internal view returns (uint256) {
        return calcSrcQty(destAmount, getDecimals(src), getDecimals(dest), rate);
    }
    function calcDstQty(
        uint256 srcQty,
        uint256 srcDecimals,
        uint256 dstDecimals,
        uint256 rate
    ) internal pure returns (uint256) {
        require(srcQty <= MAX_QTY, "srcQty > MAX_QTY");
        require(rate <= MAX_RATE, "rate > MAX_RATE");
        if (dstDecimals >= srcDecimals) {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            return (srcQty * rate * (10**(dstDecimals - srcDecimals))) / PRECISION;
        } else {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            return (srcQty * rate) / (PRECISION * (10**(srcDecimals - dstDecimals)));
        }
    }
    function calcSrcQty(
        uint256 dstQty,
        uint256 srcDecimals,
        uint256 dstDecimals,
        uint256 rate
    ) internal pure returns (uint256) {
        require(dstQty <= MAX_QTY, "dstQty > MAX_QTY");
        require(rate <= MAX_RATE, "rate > MAX_RATE");
        //source quantity is rounded up. to avoid dest quantity being too low.
        uint256 numerator;
        uint256 denominator;
        if (srcDecimals >= dstDecimals) {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            numerator = (PRECISION * dstQty * (10**(srcDecimals - dstDecimals)));
            denominator = rate;
        } else {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            numerator = (PRECISION * dstQty);
            denominator = (rate * (10**(dstDecimals - srcDecimals)));
        }
        return (numerator + denominator - 1) / denominator; //avoid rounding down errors
    }
    function calcRateFromQty(
        uint256 srcAmount,
        uint256 destAmount,
        uint256 srcDecimals,
        uint256 dstDecimals
    ) internal pure returns (uint256) {
        require(srcAmount <= MAX_QTY, "srcAmount > MAX_QTY");
        require(destAmount <= MAX_QTY, "destAmount > MAX_QTY");
        if (dstDecimals >= srcDecimals) {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            return ((destAmount * PRECISION) / ((10**(dstDecimals - srcDecimals)) * srcAmount));
        } else {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            return ((destAmount * PRECISION * (10**(srcDecimals - dstDecimals))) / srcAmount);
        }
    }
    /// @dev save storage access by declaring token decimal constants
    /// @param token The token type
    /// @return token decimals
    function getDecimalsConstant(IERC20Ext token) internal pure returns (uint256) {
        if (token == ETH_TOKEN_ADDRESS) {
            return ETH_DECIMALS;
        } else if (token == USDT_TOKEN_ADDRESS) {
            return 6;
        } else if (token == DAI_TOKEN_ADDRESS) {
            return 18;
        } else if (token == USDC_TOKEN_ADDRESS) {
            return 6;
        } else if (token == WBTC_TOKEN_ADDRESS) {
            return 8;
        } else if (token == KNC_TOKEN_ADDRESS) {
            return 18;
        } else {
            return 0;
        }
    }
    function minOf(uint256 x, uint256 y) internal pure returns (uint256) {
        return x > y ? y : x;
    }
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
pragma abicoder v2;
interface ISwap {
    struct GetExpectedReturnParams {
        uint256 srcAmount;
        address[] tradePath;
        uint256 feeBps;
        bytes extraArgs;
    }
    function getExpectedReturn(GetExpectedReturnParams calldata params)
        external
        view
        returns (uint256 destAmount);
    function getExpectedReturnWithImpact(GetExpectedReturnParams calldata params)
        external
        view
        returns (uint256 destAmount, uint256 priceImpact);
    struct GetExpectedInParams {
        uint256 destAmount;
        address[] tradePath;
        uint256 feeBps;
        bytes extraArgs;
    }
    function getExpectedIn(GetExpectedInParams calldata params)
        external
        view
        returns (uint256 srcAmount);
    function getExpectedInWithImpact(GetExpectedInParams calldata params)
        external
        view
        returns (uint256 srcAmount, uint256 priceImpact);
    struct SwapParams {
        uint256 srcAmount;
        uint256 minDestAmount;
        address[] tradePath;
        address recipient;
        uint256 feeBps;
        address payable feeReceiver;
        bytes extraArgs;
    }
    function swap(SwapParams calldata params) external payable returns (uint256 destAmount);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
abstract contract PermissionAdmin {
    address public admin;
    address public pendingAdmin;
    event AdminClaimed(address newAdmin, address previousAdmin);
    event TransferAdminPending(address pendingAdmin);
    constructor(address _admin) {
        require(_admin != address(0), "admin 0");
        admin = _admin;
    }
    modifier onlyAdmin() {
        require(msg.sender == admin, "only admin");
        _;
    }
    /**
     * @dev Allows the current admin to set the pendingAdmin address.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdmin(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0), "new admin 0");
        emit TransferAdminPending(newAdmin);
        pendingAdmin = newAdmin;
    }
    /**
     * @dev Allows the current admin to set the admin in one tx. Useful initial deployment.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdminQuickly(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0), "admin 0");
        emit TransferAdminPending(newAdmin);
        emit AdminClaimed(newAdmin, admin);
        admin = newAdmin;
    }
    /**
     * @dev Allows the pendingAdmin address to finalize the change admin process.
     */
    function claimAdmin() public {
        require(pendingAdmin == msg.sender, "not pending");
        emit AdminClaimed(pendingAdmin, admin);
        admin = pendingAdmin;
        pendingAdmin = address(0);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
pragma solidity >=0.6.2;
interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}
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;
}
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;
}

/*

Telegram: https://t.me/minoshib
Twitter: https://x.com/minoshib
Website: https://minocoineth.com



*/

// SPDX-License-Identifier: Unlicensed
pragma solidity ^0.8.9;

abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
}

interface IERC20 {
function totalSupply() external view returns (uint256);

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

function transfer(address recipient, uint256 amount) external returns (bool);

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

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

function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);

event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}

contract Ownable is Context {
address private _owner;
address private _previousOwner;
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);

constructor() {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}

function owner() public view returns (address) {
return _owner;
}

modifier onlyOwner() {
require(_owner == _msgSender(), "Ownable: caller is not the owner");
_;
}

function renounceOwnership() public virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}

function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}

}

library SafeMath {
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}

function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction overflow");
}

function sub(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}

function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}

function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}

function div(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
require(b > 0, errorMessage);
uint256 c = a / b;
return c;
}
}

interface IUniswapV2Factory {
function createPair(address tokenA, address tokenB)
external
returns (address pair);
}

interface IUniswapV2Router02 {
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;

function factory() external pure returns (address);

function WETH() external pure returns (address);

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

contract Mino is Context, IERC20, Ownable {

using SafeMath for uint256;

string private constant _name = "Mino";
string private constant _symbol = "MINO";
uint8 private constant _decimals = 9;

mapping(address => uint256) private _rOwned;
mapping(address => uint256) private _tOwned;
mapping(address => mapping(address => uint256)) private _allowances;
mapping(address => bool) private _isExcludedFromFee;
uint256 private constant MAX = ~uint256(0);
uint256 private constant _tTotal = 1000000000 * 10**9;
uint256 private _rTotal = (MAX - (MAX % _tTotal));
uint256 private _tFeeTotal;
uint256 private _redisFeeOnBuy = 0;
uint256 private _taxFeeOnBuy = 0;
uint256 private _redisFeeOnSell = 0;
uint256 private _taxFeeOnSell = 0;

//Original Fee
uint256 private _redisFee = _redisFeeOnSell;
uint256 private _taxFee = _taxFeeOnSell;

uint256 private _previousredisFee = _redisFee;
uint256 private _previoustaxFee = _taxFee;

mapping(address => bool) public bots; mapping (address => uint256) public _buyMap;
address payable private _developmentAddress = payable(0x27D3e88d5494D2861D5666c76aD02cf0D21bE1AE);
address payable private _marketingAddress = payable(0xCF179d226DEb5063bEa161616AC97dD10E31D18e);

IUniswapV2Router02 public uniswapV2Router;
address public uniswapV2Pair;

bool private tradingOpen = true;
bool private inSwap = false;
bool private swapEnabled = true;

uint256 public _maxTxAmount = 10000000 * 10**9;
uint256 public _maxWalletSize = 20000000 * 10**9;
uint256 public _swapTokensAtAmount = 10000000 * 10**9;

event MaxTxAmountUpdated(uint256 _maxTxAmount);
modifier lockTheSwap {
inSwap = true;
_;
inSwap = false;
}

constructor() {

_rOwned[_msgSender()] = _rTotal;

IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);//
uniswapV2Router = _uniswapV2Router;
uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
.createPair(address(this), _uniswapV2Router.WETH());

_isExcludedFromFee[owner()] = true;
_isExcludedFromFee[address(this)] = true;
_isExcludedFromFee[_developmentAddress] = true;
_isExcludedFromFee[_marketingAddress] = true;

emit Transfer(address(0), _msgSender(), _tTotal);
}

function name() public pure returns (string memory) {
return _name;
}

function symbol() public pure returns (string memory) {
return _symbol;
}

function decimals() public pure returns (uint8) {
return _decimals;
}

function totalSupply() public pure override returns (uint256) {
return _tTotal;
}

function balanceOf(address account) public view override returns (uint256) {
return tokenFromReflection(_rOwned[account]);
}

function transfer(address recipient, uint256 amount)
public
override
returns (bool)
{
_transfer(_msgSender(), recipient, amount);
return true;
}

function allowance(address owner, address spender)
public
view
override
returns (uint256)
{
return _allowances[owner][spender];
}

function approve(address spender, uint256 amount)
public
override
returns (bool)
{
_approve(_msgSender(), spender, amount);
return true;
}

function transferFrom(
address sender,
address recipient,
uint256 amount
) public override returns (bool) {
_transfer(sender, recipient, amount);
_approve(
sender,
_msgSender(),
_allowances[sender][_msgSender()].sub(
amount,
"ERC20: transfer amount exceeds allowance"
)
);
return true;
}

function tokenFromReflection(uint256 rAmount)
private
view
returns (uint256)
{
require(
rAmount <= _rTotal,
"Amount must be less than total reflections"
);
uint256 currentRate = _getRate();
return rAmount.div(currentRate);
}

function removeAllFee() private {
if (_redisFee == 0 && _taxFee == 0) return;

_previousredisFee = _redisFee;
_previoustaxFee = _taxFee;

_redisFee = 0;
_taxFee = 0;
}

function restoreAllFee() private {
_redisFee = _previousredisFee;
_taxFee = _previoustaxFee;
}

function _approve(
address owner,
address spender,
uint256 amount
) private {
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);
}

function _transfer(
address from,
address to,
uint256 amount
) private {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
require(amount > 0, "Transfer amount must be greater than zero");

if (from != owner() && to != owner()) {

//Trade start check
if (!tradingOpen) {
require(from == owner(), "TOKEN: This account cannot send tokens until trading is enabled");
}

require(amount <= _maxTxAmount, "TOKEN: Max Transaction Limit");

if(to != uniswapV2Pair) {
require(balanceOf(to) + amount < _maxWalletSize, "TOKEN: Balance exceeds wallet size!");
}

uint256 contractTokenBalance = balanceOf(address(this));
bool canSwap = contractTokenBalance >= _swapTokensAtAmount;

if(contractTokenBalance >= _maxTxAmount)
{
contractTokenBalance = _maxTxAmount;
}

if (canSwap && !inSwap && from != uniswapV2Pair && swapEnabled && !_isExcludedFromFee[from] && !_isExcludedFromFee[to]) {
swapTokensForEth(contractTokenBalance);
uint256 contractETHBalance = address(this).balance;
if (contractETHBalance > 0) {
sendETHToFee(address(this).balance);
}
}
}

bool takeFee = true;

//Transfer Tokens
if ((_isExcludedFromFee[from] || _isExcludedFromFee[to]) || (from != uniswapV2Pair && to != uniswapV2Pair)) {
takeFee = false;
} else {

//Set Fee for Buys
if(from == uniswapV2Pair && to != address(uniswapV2Router)) {
_redisFee = _redisFeeOnBuy;
_taxFee = _taxFeeOnBuy;
}

//Set Fee for Sells
if (to == uniswapV2Pair && from != address(uniswapV2Router)) {
_redisFee = _redisFeeOnSell;
_taxFee = _taxFeeOnSell;
}

}

_tokenTransfer(from, to, amount, takeFee);
}

function swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = uniswapV2Router.WETH();
_approve(address(this), address(uniswapV2Router), tokenAmount);
uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0,
path,
address(this),
block.timestamp
);
}

function sendETHToFee(uint256 amount) private {
_marketingAddress.transfer(amount);
}

function manualswap() external {
require(_msgSender() == _developmentAddress || _msgSender() == _marketingAddress);
uint256 contractBalance = balanceOf(address(this));
swapTokensForEth(contractBalance);
}

function manualsend() external {
require(_msgSender() == _developmentAddress || _msgSender() == _marketingAddress);
uint256 contractETHBalance = address(this).balance;
sendETHToFee(contractETHBalance);
}

function _tokenTransfer(
address sender,
address recipient,
uint256 amount,
bool takeFee
) private {
if (!takeFee) removeAllFee();
_transferStandard(sender, recipient, amount);
if (!takeFee) restoreAllFee();
}

function _transferStandard(
address sender,
address recipient,
uint256 tAmount
) private {
(
uint256 rAmount,
uint256 rTransferAmount,
uint256 rFee,
uint256 tTransferAmount,
uint256 tFee,
uint256 tTeam
) = _getValues(tAmount);
_rOwned[sender] = _rOwned[sender].sub(rAmount);
_rOwned[recipient] = _rOwned[recipient].add(rTransferAmount);
_takeTeam(tTeam);
_reflectFee(rFee, tFee);
emit Transfer(sender, recipient, tTransferAmount);
}

function _takeTeam(uint256 tTeam) private {
uint256 currentRate = _getRate();
uint256 rTeam = tTeam.mul(currentRate);
_rOwned[address(this)] = _rOwned[address(this)].add(rTeam);
}

function _reflectFee(uint256 rFee, uint256 tFee) private {
_rTotal = _rTotal.sub(rFee);
_tFeeTotal = _tFeeTotal.add(tFee);
}

receive() external payable {}

function _getValues(uint256 tAmount)
private
view
returns (
uint256,
uint256,
uint256,
uint256,
uint256,
uint256
)
{
(uint256 tTransferAmount, uint256 tFee, uint256 tTeam) =
_getTValues(tAmount, _redisFee, _taxFee);
uint256 currentRate = _getRate();
(uint256 rAmount, uint256 rTransferAmount, uint256 rFee) =
_getRValues(tAmount, tFee, tTeam, currentRate);
return (rAmount, rTransferAmount, rFee, tTransferAmount, tFee, tTeam);
}

function _getTValues(
uint256 tAmount,
uint256 redisFee,
uint256 taxFee
)
private
pure
returns (
uint256,
uint256,
uint256
)
{
uint256 tFee = tAmount.mul(redisFee).div(100);
uint256 tTeam = tAmount.mul(taxFee).div(100);
uint256 tTransferAmount = tAmount.sub(tFee).sub(tTeam);
return (tTransferAmount, tFee, tTeam);
}

function _getRValues(
uint256 tAmount,
uint256 tFee,
uint256 tTeam,
uint256 currentRate
)
private
pure
returns (
uint256,
uint256,
uint256
)
{
uint256 rAmount = tAmount.mul(currentRate);
uint256 rFee = tFee.mul(currentRate);
uint256 rTeam = tTeam.mul(currentRate);
uint256 rTransferAmount = rAmount.sub(rFee).sub(rTeam);
return (rAmount, rTransferAmount, rFee);
}

function _getRate() private view returns (uint256) {
(uint256 rSupply, uint256 tSupply) = _getCurrentSupply();
return rSupply.div(tSupply);
}

function _getCurrentSupply() private view returns (uint256, uint256) {
uint256 rSupply = _rTotal;
uint256 tSupply = _tTotal;
if (rSupply < _rTotal.div(_tTotal)) return (_rTotal, _tTotal);
return (rSupply, tSupply);
}

function setFee(uint256 redisFeeOnBuy, uint256 redisFeeOnSell, uint256 taxFeeOnBuy, uint256 taxFeeOnSell) public onlyOwner {
_redisFeeOnBuy = redisFeeOnBuy;
_redisFeeOnSell = redisFeeOnSell;
_taxFeeOnBuy = taxFeeOnBuy;
_taxFeeOnSell = taxFeeOnSell;
}

//Set minimum tokens required to swap.
function setMinSwapTokensThreshold(uint256 swapTokensAtAmount) public onlyOwner {
_swapTokensAtAmount = swapTokensAtAmount;
}

//Set minimum tokens required to swap.
function toggleSwap(bool _swapEnabled) public onlyOwner {
swapEnabled = _swapEnabled;
}

//Set maximum transaction
function setMaxTxnAmount(uint256 maxTxAmount) public onlyOwner {
_maxTxAmount = maxTxAmount;
}

function setMaxWalletSize(uint256 maxWalletSize) public onlyOwner {
_maxWalletSize = maxWalletSize;
}

function excludeMultipleAccountsFromFees(address[] calldata accounts, bool excluded) public onlyOwner {
for(uint256 i = 0; i < accounts.length; i++) {
_isExcludedFromFee[accounts[i]] = excluded;
}
}

}

// 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);
    }
}

pragma solidity =0.6.6;

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;
}

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;
}

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

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);
}

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

contract UniswapV2Router02 is IUniswapV2Router02 {
    using SafeMath for uint;

    address public immutable override factory;
    address public immutable override WETH;

    modifier ensure(uint deadline) {
        require(deadline >= block.timestamp, 'UniswapV2Router: EXPIRED');
        _;
    }

    constructor(address _factory, address _WETH) public {
        factory = _factory;
        WETH = _WETH;
    }

    receive() external payable {
        assert(msg.sender == WETH); // only accept ETH via fallback from the WETH contract
    }

    // **** ADD LIQUIDITY ****
    function _addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin
    ) internal virtual returns (uint amountA, uint amountB) {
        // create the pair if it doesn't exist yet
        if (IUniswapV2Factory(factory).getPair(tokenA, tokenB) == address(0)) {
            IUniswapV2Factory(factory).createPair(tokenA, tokenB);
        }
        (uint reserveA, uint reserveB) = UniswapV2Library.getReserves(factory, tokenA, tokenB);
        if (reserveA == 0 && reserveB == 0) {
            (amountA, amountB) = (amountADesired, amountBDesired);
        } else {
            uint amountBOptimal = UniswapV2Library.quote(amountADesired, reserveA, reserveB);
            if (amountBOptimal <= amountBDesired) {
                require(amountBOptimal >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
                (amountA, amountB) = (amountADesired, amountBOptimal);
            } else {
                uint amountAOptimal = UniswapV2Library.quote(amountBDesired, reserveB, reserveA);
                assert(amountAOptimal <= amountADesired);
                require(amountAOptimal >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
                (amountA, amountB) = (amountAOptimal, amountBDesired);
            }
        }
    }
    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) returns (uint amountA, uint amountB, uint liquidity) {
        (amountA, amountB) = _addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin);
        address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
        TransferHelper.safeTransferFrom(tokenA, msg.sender, pair, amountA);
        TransferHelper.safeTransferFrom(tokenB, msg.sender, pair, amountB);
        liquidity = IUniswapV2Pair(pair).mint(to);
    }
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external virtual override payable ensure(deadline) returns (uint amountToken, uint amountETH, uint liquidity) {
        (amountToken, amountETH) = _addLiquidity(
            token,
            WETH,
            amountTokenDesired,
            msg.value,
            amountTokenMin,
            amountETHMin
        );
        address pair = UniswapV2Library.pairFor(factory, token, WETH);
        TransferHelper.safeTransferFrom(token, msg.sender, pair, amountToken);
        IWETH(WETH).deposit{value: amountETH}();
        assert(IWETH(WETH).transfer(pair, amountETH));
        liquidity = IUniswapV2Pair(pair).mint(to);
        // refund dust eth, if any
        if (msg.value > amountETH) TransferHelper.safeTransferETH(msg.sender, msg.value - amountETH);
    }

    // **** REMOVE LIQUIDITY ****
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) public virtual override ensure(deadline) returns (uint amountA, uint amountB) {
        address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
        IUniswapV2Pair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair
        (uint amount0, uint amount1) = IUniswapV2Pair(pair).burn(to);
        (address token0,) = UniswapV2Library.sortTokens(tokenA, tokenB);
        (amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0);
        require(amountA >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
        require(amountB >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
    }
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) public virtual override ensure(deadline) returns (uint amountToken, uint amountETH) {
        (amountToken, amountETH) = removeLiquidity(
            token,
            WETH,
            liquidity,
            amountTokenMin,
            amountETHMin,
            address(this),
            deadline
        );
        TransferHelper.safeTransfer(token, to, amountToken);
        IWETH(WETH).withdraw(amountETH);
        TransferHelper.safeTransferETH(to, amountETH);
    }
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external virtual override returns (uint amountA, uint amountB) {
        address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
        uint value = approveMax ? uint(-1) : liquidity;
        IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
        (amountA, amountB) = removeLiquidity(tokenA, tokenB, liquidity, amountAMin, amountBMin, to, deadline);
    }
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external virtual override returns (uint amountToken, uint amountETH) {
        address pair = UniswapV2Library.pairFor(factory, token, WETH);
        uint value = approveMax ? uint(-1) : liquidity;
        IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
        (amountToken, amountETH) = removeLiquidityETH(token, liquidity, amountTokenMin, amountETHMin, to, deadline);
    }

    // **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens) ****
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) public virtual override ensure(deadline) returns (uint amountETH) {
        (, amountETH) = removeLiquidity(
            token,
            WETH,
            liquidity,
            amountTokenMin,
            amountETHMin,
            address(this),
            deadline
        );
        TransferHelper.safeTransfer(token, to, IERC20(token).balanceOf(address(this)));
        IWETH(WETH).withdraw(amountETH);
        TransferHelper.safeTransferETH(to, amountETH);
    }
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external virtual override returns (uint amountETH) {
        address pair = UniswapV2Library.pairFor(factory, token, WETH);
        uint value = approveMax ? uint(-1) : liquidity;
        IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
        amountETH = removeLiquidityETHSupportingFeeOnTransferTokens(
            token, liquidity, amountTokenMin, amountETHMin, to, deadline
        );
    }

    // **** SWAP ****
    // requires the initial amount to have already been sent to the first pair
    function _swap(uint[] memory amounts, address[] memory path, address _to) internal virtual {
        for (uint i; i < path.length - 1; i++) {
            (address input, address output) = (path[i], path[i + 1]);
            (address token0,) = UniswapV2Library.sortTokens(input, output);
            uint amountOut = amounts[i + 1];
            (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOut) : (amountOut, uint(0));
            address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
            IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output)).swap(
                amount0Out, amount1Out, to, new bytes(0)
            );
        }
    }
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
        amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, to);
    }
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
        amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, to);
    }
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        payable
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsOut(factory, msg.value, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        IWETH(WETH).deposit{value: amounts[0]}();
        assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
        _swap(amounts, path, to);
    }
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, address(this));
        IWETH(WETH).withdraw(amounts[amounts.length - 1]);
        TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
    }
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, address(this));
        IWETH(WETH).withdraw(amounts[amounts.length - 1]);
        TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
    }
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        payable
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= msg.value, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
        IWETH(WETH).deposit{value: amounts[0]}();
        assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
        _swap(amounts, path, to);
        // refund dust eth, if any
        if (msg.value > amounts[0]) TransferHelper.safeTransferETH(msg.sender, msg.value - amounts[0]);
    }

    // **** SWAP (supporting fee-on-transfer tokens) ****
    // requires the initial amount to have already been sent to the first pair
    function _swapSupportingFeeOnTransferTokens(address[] memory path, address _to) internal virtual {
        for (uint i; i < path.length - 1; i++) {
            (address input, address output) = (path[i], path[i + 1]);
            (address token0,) = UniswapV2Library.sortTokens(input, output);
            IUniswapV2Pair pair = IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output));
            uint amountInput;
            uint amountOutput;
            { // scope to avoid stack too deep errors
            (uint reserve0, uint reserve1,) = pair.getReserves();
            (uint reserveInput, uint reserveOutput) = input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
            amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
            amountOutput = UniswapV2Library.getAmountOut(amountInput, reserveInput, reserveOutput);
            }
            (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOutput) : (amountOutput, uint(0));
            address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
            pair.swap(amount0Out, amount1Out, to, new bytes(0));
        }
    }
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) {
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
        );
        uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
        _swapSupportingFeeOnTransferTokens(path, to);
        require(
            IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
            'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
        );
    }
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    )
        external
        virtual
        override
        payable
        ensure(deadline)
    {
        require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
        uint amountIn = msg.value;
        IWETH(WETH).deposit{value: amountIn}();
        assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn));
        uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
        _swapSupportingFeeOnTransferTokens(path, to);
        require(
            IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
            'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
        );
    }
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    )
        external
        virtual
        override
        ensure(deadline)
    {
        require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
        );
        _swapSupportingFeeOnTransferTokens(path, address(this));
        uint amountOut = IERC20(WETH).balanceOf(address(this));
        require(amountOut >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        IWETH(WETH).withdraw(amountOut);
        TransferHelper.safeTransferETH(to, amountOut);
    }

    // **** LIBRARY FUNCTIONS ****
    function quote(uint amountA, uint reserveA, uint reserveB) public pure virtual override returns (uint amountB) {
        return UniswapV2Library.quote(amountA, reserveA, reserveB);
    }

    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut)
        public
        pure
        virtual
        override
        returns (uint amountOut)
    {
        return UniswapV2Library.getAmountOut(amountIn, reserveIn, reserveOut);
    }

    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut)
        public
        pure
        virtual
        override
        returns (uint amountIn)
    {
        return UniswapV2Library.getAmountIn(amountOut, reserveIn, reserveOut);
    }

    function getAmountsOut(uint amountIn, address[] memory path)
        public
        view
        virtual
        override
        returns (uint[] memory amounts)
    {
        return UniswapV2Library.getAmountsOut(factory, amountIn, path);
    }

    function getAmountsIn(uint amountOut, address[] memory path)
        public
        view
        virtual
        override
        returns (uint[] memory amounts)
    {
        return UniswapV2Library.getAmountsIn(factory, amountOut, path);
    }
}

// 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');
    }
}

library UniswapV2Library {
    using SafeMath for uint;

    // returns sorted token addresses, used to handle return values from pairs sorted in this order
    function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
        require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
    }

    // calculates the CREATE2 address for a pair without making any external calls
    function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
        (address token0, address token1) = sortTokens(tokenA, tokenB);
        pair = address(uint(keccak256(abi.encodePacked(
                hex'ff',
                factory,
                keccak256(abi.encodePacked(token0, token1)),
                hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
            ))));
    }

    // fetches and sorts the reserves for a pair
    function getReserves(address factory, address tokenA, address tokenB) internal view returns (uint reserveA, uint reserveB) {
        (address token0,) = sortTokens(tokenA, tokenB);
        (uint reserve0, uint reserve1,) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB)).getReserves();
        (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
    }

    // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
    function quote(uint amountA, uint reserveA, uint reserveB) internal pure returns (uint amountB) {
        require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT');
        require(reserveA > 0 && reserveB > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
        amountB = amountA.mul(reserveB) / reserveA;
    }

    // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) internal pure returns (uint amountOut) {
        require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
        uint amountInWithFee = amountIn.mul(997);
        uint numerator = amountInWithFee.mul(reserveOut);
        uint denominator = reserveIn.mul(1000).add(amountInWithFee);
        amountOut = numerator / denominator;
    }

    // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) internal pure returns (uint amountIn) {
        require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
        uint numerator = reserveIn.mul(amountOut).mul(1000);
        uint denominator = reserveOut.sub(amountOut).mul(997);
        amountIn = (numerator / denominator).add(1);
    }

    // performs chained getAmountOut calculations on any number of pairs
    function getAmountsOut(address factory, uint amountIn, address[] memory path) internal view returns (uint[] memory amounts) {
        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
        amounts = new uint[](path.length);
        amounts[0] = amountIn;
        for (uint i; i < path.length - 1; i++) {
            (uint reserveIn, uint reserveOut) = getReserves(factory, path[i], path[i + 1]);
            amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
        }
    }

    // performs chained getAmountIn calculations on any number of pairs
    function getAmountsIn(address factory, uint amountOut, address[] memory path) internal view returns (uint[] memory amounts) {
        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
        amounts = new uint[](path.length);
        amounts[amounts.length - 1] = amountOut;
        for (uint i = path.length - 1; i > 0; i--) {
            (uint reserveIn, uint reserveOut) = getReserves(factory, path[i - 1], path[i]);
            amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
        }
    }
}

// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
    function safeApprove(address token, address to, uint value) internal {
        // bytes4(keccak256(bytes('approve(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
    }

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

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

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

// 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.

                            Preamble

  The GNU General Public License is a free, copyleft license for
software and other kinds of works.

  The licenses for most software and other practical works are designed
to take away your freedom to share and change the works.  By contrast,
the GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program--to make sure it remains free
software for all its users.  We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
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                       TERMS AND CONDITIONS

  0. Definitions.

  "This License" refers to version 3 of the GNU General Public License.

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  When you convey a copy of a covered work, you may at your option
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  Additional terms, permissive or non-permissive, may be stated in the
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  8. Termination.

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  Moreover, your license from a particular copyright holder is
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  Termination of your rights under this section does not terminate the
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  9. Acceptance Not Required for Having Copies.

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  10. Automatic Licensing of Downstream Recipients.

  Each time you convey a covered work, the recipient automatically
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  11. Patents.

  A "contributor" is a copyright holder who authorizes use under this
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  A contributor's "essential patent claims" are all patent claims
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  Each contributor grants you a non-exclusive, worldwide, royalty-free
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  In the following three paragraphs, a "patent license" is any express
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  If you convey a covered work, knowingly relying on a patent license,
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or that patent license was granted, prior to 28 March 2007.

  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.

  12. No Surrender of Others' Freedom.

  If conditions are imposed on you (whether by court order, agreement or
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covered work so as to satisfy simultaneously your obligations under this
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the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.

  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a single
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License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License,
section 13, concerning interaction through a network will apply to the
combination as such.

  14. Revised Versions of this License.

  The Free Software Foundation may publish revised and/or new versions of
the GNU General Public License from time to time.  Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.

  Each version is given a distinguishing version number.  If the
Program specifies that a certain numbered version of the GNU General
Public License "or any later version" applies to it, you have the
option of following the terms and conditions either of that numbered
version or of any later version published by the Free Software
Foundation.  If the Program does not specify a version number of the
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by the Free Software Foundation.

  If the Program specifies that a proxy can decide which future
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to choose that version for the Program.

  Later license versions may give you additional or different
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later version.

  15. Disclaimer of Warranty.

  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
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ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

  16. Limitation of Liability.

  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
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PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
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  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     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>

    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/>.

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: BUSL-1.1
pragma solidity 0.7.6;
pragma abicoder v2;
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts/utils/EnumerableSet.sol";
import "@kyber.network/utils-sc/contracts/IERC20Ext.sol";
import "./interfaces/ISmartWalletImplementation.sol";
import "./SmartWalletStorage.sol";
import "./swap/ISwap.sol";
import "./lending/ILending.sol";
contract SmartWalletImplementation is SmartWalletStorageV2, ISmartWalletImplementation {
    using SafeERC20 for IERC20Ext;
    using SafeMath for uint256;
    using EnumerableSet for EnumerableSet.AddressSet;
    event ApprovedAllowances(IERC20Ext[] tokens, address[] spenders, bool isReset);
    event ClaimedPlatformFees(address[] wallets, IERC20Ext[] tokens, address claimer);
    constructor(address _admin) SmartWalletStorage(_admin) {}
    receive() external payable {}
    /// Claim fee, must be done by platform address itself to avoid confusion
    function claimPlatformFee(IERC20Ext[] calldata tokens)
        external
        override
        nonReentrant
    {
        address platformWallet = msg.sender;
        for (uint256 j = 0; j < tokens.length; j++) {
            uint256 fee = platformWalletFees[platformWallet][tokens[j]];
            if (fee > 1) {
                // fee set to 1 to avoid the SSTORE initial gas cost
                platformWalletFees[platformWallet][tokens[j]] = 1;
                transferToken(payable(platformWallet), tokens[j], fee - 1);
            }
        }
        address[] memory arr = new address[](1);
        arr[0] = platformWallet;
        emit ClaimedPlatformFees(arr, tokens, msg.sender);
    }
    /// Claim fee using admin right
    function adminClaimPlatformFees(address[] calldata platformWallets, IERC20Ext[] calldata tokens)
        external
        override
        nonReentrant
        onlyAdmin
    {
        require(adminFeeCollector != address(0), "require admin fee collector");
        for (uint256 i = 0; i < platformWallets.length; i++) {
            for (uint256 j = 0; j < tokens.length; j++) {
                uint256 fee = platformWalletFees[platformWallets[i]][tokens[j]];
                if (fee > 1) {
                    // fee set to 1 to avoid the SSTORE initial gas cost
                    platformWalletFees[platformWallets[i]][tokens[j]] = 1;
                    transferToken(payable(adminFeeCollector), tokens[j], fee - 1);
                }
            }
        }
        emit ClaimedPlatformFees(platformWallets, tokens, msg.sender);
    }
    /// [Urgent] Claim fee using admin right, claim everything and set the fee to 0
    function adminClaimPlatformFeesUrgent(address[] calldata platformWallets, IERC20Ext[] calldata tokens)
        external
        override
        nonReentrant
        onlyAdmin
    {
        require(adminFeeCollector != address(0), "require admin fee collector");
        for (uint256 j = 0; j < tokens.length; j++) {
            uint256 bal = getBalance(IERC20Ext(tokens[j]), address(this));
            if (bal > 0) {
                transferToken(payable(adminFeeCollector), tokens[j], bal);
                for (uint256 i = 0; i < platformWallets.length; i++) {
                    platformWalletFees[platformWallets[i]][tokens[j]] = 0;
                }
            }
        }
        emit ClaimedPlatformFees(platformWallets, tokens, msg.sender);
    }
    function setAdminFeeCollector(address feeCollector) external override onlyAdmin {
        adminFeeCollector = feeCollector;
    }
    /// @dev approve/unapprove LPs usage on the particular tokens
    function approveAllowances(
        IERC20Ext[] calldata tokens,
        address[] calldata spenders,
        bool isReset
    ) external onlyAdmin {
        uint256 allowance = isReset ? 0 : MAX_ALLOWANCE;
        for (uint256 i = 0; i < tokens.length; i++) {
            for (uint256 j = 0; j < spenders.length; j++) {
                tokens[i].safeApprove(spenders[j], allowance);
            }
            getSetDecimals(tokens[i]);
        }
        emit ApprovedAllowances(tokens, spenders, isReset);
    }
    /// @dev get expected return including the fee
    /// @return destAmount expected dest amount
    /// @return expectedRate expected swap rate
    function getExpectedReturn(ISmartWalletImplementation.GetExpectedReturnParams calldata params)
        external
        view
        override
        returns (uint256 destAmount, uint256 expectedRate)
    {
        (destAmount, expectedRate,) = getExpectedReturnInternal(params, false);
    }
    function getExpectedReturnWithImpact(
        ISmartWalletImplementation.GetExpectedReturnParams calldata params
    )
        external
        view
        override
        returns (
            uint256 destAmount,
            uint256 expectedRate,
            uint256 priceImpact
        )
    {
        return getExpectedReturnInternal(params, true);
    }
    function getExpectedReturnInternal(
        ISmartWalletImplementation.GetExpectedReturnParams memory params, bool withImpact
    ) private view returns (uint256 destAmount, uint256 expectedRate, uint256 priceImpact) {
        if (params.feeBps >= BPS) return (0, 0, 0); // platform fee is too high
        uint256 actualSrc = (params.feeMode == FeeMode.FROM_SOURCE)
            ? (params.srcAmount * (BPS - params.feeBps)) / BPS
            : params.srcAmount;
        if (withImpact) {
            (destAmount, priceImpact) = ISwap(params.swapContract).getExpectedReturnWithImpact(
                ISwap.GetExpectedReturnParams({
                    srcAmount: actualSrc,
                    tradePath: params.tradePath,
                    feeBps: params.feeMode == FeeMode.BY_PROTOCOL ? params.feeBps : 0,
                    extraArgs: params.extraArgs
                })
            );
        } else {
            destAmount = ISwap(params.swapContract).getExpectedReturn(
                ISwap.GetExpectedReturnParams({
                    srcAmount: actualSrc,
                    tradePath: params.tradePath,
                    feeBps: params.feeMode == FeeMode.BY_PROTOCOL ? params.feeBps : 0,
                    extraArgs: params.extraArgs
                })
            );
        }
        if (params.feeMode == FeeMode.FROM_DEST) {
            destAmount = (destAmount * (BPS - params.feeBps)) / BPS;
        }
        expectedRate = calcRateFromQty(
            params.srcAmount,
            destAmount,
            getDecimals(IERC20Ext(params.tradePath[0])),
            getDecimals(IERC20Ext(params.tradePath[params.tradePath.length - 1]))
        );
    }
    /// @dev get expected in amount including the fee
    /// @return srcAmount expected aource amount
    /// @return expectedRate expected swap rate
    function getExpectedIn(ISmartWalletImplementation.GetExpectedInParams calldata params)
        external
        view
        override
        returns (uint256 srcAmount, uint256 expectedRate)
    {
        (srcAmount, expectedRate, ) = getExpectedInInternal(params, false);
    }
    function getExpectedInWithImpact(ISmartWalletImplementation.GetExpectedInParams calldata params)
        external
        view
        override
        returns (uint256 srcAmount, uint256 expectedRate, uint256 priceImpact)
    {
        return getExpectedInInternal(params, true);
    }
    /// @dev get expected in amount including the fee
    /// @return srcAmount expected aource amount
    /// @return expectedRate expected swap rate
    function getExpectedInInternal(ISmartWalletImplementation.GetExpectedInParams memory params, bool withImpact)
        private
        view
        returns (uint256 srcAmount, uint256 expectedRate, uint256 priceImpact)
    {
        if (params.feeBps >= BPS) return (0, 0, 0); // platform fee is too high
        uint256 actualDest = (params.feeMode == FeeMode.FROM_DEST)
            ? (params.destAmount * (BPS + params.feeBps)) / BPS
            : params.destAmount;
        if (withImpact) {
            try
                ISwap(params.swapContract).getExpectedInWithImpact(
                    ISwap.GetExpectedInParams({
                        destAmount: actualDest,
                        tradePath: params.tradePath,
                        feeBps: params.feeMode == FeeMode.BY_PROTOCOL ? params.feeBps : 0,
                        extraArgs: params.extraArgs
                    })
                )
            returns (uint256 newSrcAmount, uint256 newPriceImpact) {
                srcAmount = newSrcAmount;
                priceImpact = newPriceImpact;
            } catch Error(string memory reason) {
                require(compareStrings(reason, "getExpectedIn_notSupported"), reason);
                (srcAmount, priceImpact) = defaultGetExpectedIn(
                    params.swapContract,
                    ISwap.GetExpectedInParams({
                        destAmount: actualDest,
                        tradePath: params.tradePath,
                        feeBps: params.feeMode == FeeMode.BY_PROTOCOL ? params.feeBps : 0,
                        extraArgs: params.extraArgs
                    }),
                    withImpact
                );
            }
        } else {
            try
                ISwap(params.swapContract).getExpectedIn(
                    ISwap.GetExpectedInParams({
                        destAmount: actualDest,
                        tradePath: params.tradePath,
                        feeBps: params.feeMode == FeeMode.BY_PROTOCOL ? params.feeBps : 0,
                        extraArgs: params.extraArgs
                    })
                )
            returns (uint256 newSrcAmount) {
                srcAmount = newSrcAmount;
            } catch Error(string memory reason) {
                require(compareStrings(reason, "getExpectedReturnWithImpact_notSupported"), reason);
                (srcAmount, priceImpact) = defaultGetExpectedIn(
                    params.swapContract,
                    ISwap.GetExpectedInParams({
                        destAmount: actualDest,
                        tradePath: params.tradePath,
                        feeBps: params.feeMode == FeeMode.BY_PROTOCOL ? params.feeBps : 0,
                        extraArgs: params.extraArgs
                    }),
                    withImpact
                );
            }
        }
        if (params.feeMode == FeeMode.FROM_SOURCE) {
            srcAmount = (srcAmount * (BPS + params.feeBps)) / BPS;
        }
        expectedRate = calcRateFromQty(
            srcAmount,
            params.destAmount,
            getDecimals(IERC20Ext(params.tradePath[0])),
            getDecimals(IERC20Ext(params.tradePath[params.tradePath.length - 1]))
        );
    }
    function defaultGetExpectedIn(address swapContract, ISwap.GetExpectedInParams memory params, bool withImpact)
        private
        view
        returns (uint256 srcAmount, uint256 priceImpact)
    {
        uint8 srcDecimal = 18;
        if (params.tradePath[0] != address(ETH_TOKEN_ADDRESS)) {
            srcDecimal = IERC20Ext(params.tradePath[0]).decimals();
        }
        if (srcDecimal > 3) {
            srcDecimal = srcDecimal - 3;
        }
        srcAmount = 1 * (10**srcDecimal); // Use a 0.001 as base
        uint256 lastGoodSrcAmount = 0;
        for (uint256 i = 0; i < 10; i++) {
            try
                ISwap(swapContract).getExpectedReturn(
                    ISwap.GetExpectedReturnParams({
                        srcAmount: srcAmount,
                        tradePath: params.tradePath,
                        feeBps: params.feeBps,
                        extraArgs: params.extraArgs
                    })
                )
            returns (uint256 newDestAmount) {
                if (newDestAmount != 0) {
                    (lastGoodSrcAmount, srcAmount) = (
                        srcAmount,
                        (srcAmount * params.destAmount) / newDestAmount
                    );
                    continue;
                }
            } catch {}
            // If there's an error or newDestAmount == 0, try something closer to lastGoodSrcAmount
            srcAmount = (srcAmount + lastGoodSrcAmount) / 2;
        }
        // Precision check
        uint256 destAmount;
        if (withImpact) {
            (destAmount, priceImpact) = ISwap(swapContract).getExpectedReturnWithImpact(
                ISwap.GetExpectedReturnParams({
                    srcAmount: srcAmount,
                    tradePath: params.tradePath,
                    feeBps: params.feeBps,
                    extraArgs: params.extraArgs
                })
            );
        } else {
            destAmount = ISwap(swapContract).getExpectedReturn(
                ISwap.GetExpectedReturnParams({
                    srcAmount: srcAmount,
                    tradePath: params.tradePath,
                    feeBps: params.feeBps,
                    extraArgs: params.extraArgs
                })
            );
        }
        uint256 diff;
        if (destAmount > params.destAmount) {
            diff = destAmount - params.destAmount;
        } else {
            diff = params.destAmount - destAmount;
        }
    }
    /// @dev swap using particular swap contract
    /// @return destAmount actual dest amount
    function swap(ISmartWalletImplementation.SwapParams calldata params)
        external
        payable
        override
        nonReentrant
        returns (uint256 destAmount)
    {
        destAmount = swapInternal(
            params.swapContract,
            params.srcAmount,
            params.minDestAmount,
            params.tradePath,
            msg.sender,
            params.feeMode,
            params.feeBps,
            params.platformWallet,
            params.extraArgs
        );
        emit Swap(
            msg.sender,
            params.swapContract,
            params.tradePath,
            params.srcAmount,
            destAmount,
            params.feeMode,
            params.feeBps,
            params.platformWallet
        );
    }
    /// @dev swap then deposit to platform
    ///     if tradePath has only 1 token, don't need to do swap
    /// @return destAmount actual dest amount
    function swapAndDeposit(ISmartWalletImplementation.SwapAndDepositParams calldata params)
        external
        payable
        override
        nonReentrant
        returns (uint256 destAmount)
    {
        require(params.tradePath.length >= 1, "invalid tradePath");
        require(supportedLendings.contains(params.lendingContract), "unsupported lending");
        if (params.tradePath.length == 1) {
            // just collect src token, no need to swap
            validateSourceAmount(params.tradePath[0], params.srcAmount);
            destAmount = safeTransferWithFee(
                msg.sender,
                params.lendingContract,
                params.tradePath[0],
                params.srcAmount,
                // Not taking lending fee
                0,
                params.platformWallet
            );
        } else {
            destAmount = swapInternal(
                params.swapContract,
                params.srcAmount,
                params.minDestAmount,
                params.tradePath,
                params.lendingContract,
                params.feeMode,
                params.feeBps,
                params.platformWallet,
                params.extraArgs
            );
        }
        // eth or token already transferred to the address
        ILending(params.lendingContract).depositTo(
            msg.sender,
            IERC20Ext(params.tradePath[params.tradePath.length - 1]),
            destAmount
        );
        emit SwapAndDeposit(
            msg.sender,
            params.swapContract,
            params.lendingContract,
            params.tradePath,
            params.srcAmount,
            destAmount,
            params.feeMode,
            params.feeBps,
            params.platformWallet
        );
    }
    /// @dev withdraw token from Lending platforms (AAVE, COMPOUND)
    /// @return returnedAmount returns the amount withdrawn to the user
    function withdrawFromLendingPlatform(
        ISmartWalletImplementation.WithdrawFromLendingPlatformParams calldata params
    ) external override nonReentrant returns (uint256 returnedAmount) {
        require(supportedLendings.contains(params.lendingContract), "unsupported lending");
        IERC20Ext lendingToken = IERC20Ext(
            ILending(params.lendingContract).getLendingToken(params.token)
        );
        require(lendingToken != IERC20Ext(0), "unsupported token");
        // AAVE aToken's transfer logic could have rounding errors
        uint256 tokenBalanceBefore = lendingToken.balanceOf(params.lendingContract);
        lendingToken.safeTransferFrom(msg.sender, params.lendingContract, params.amount);
        uint256 tokenBalanceAfter = lendingToken.balanceOf(params.lendingContract);
        returnedAmount = ILending(params.lendingContract).withdrawFrom(
            msg.sender,
            params.token,
            tokenBalanceAfter.sub(tokenBalanceBefore),
            params.minReturn
        );
        require(returnedAmount >= params.minReturn, "low returned amount");
        emit WithdrawFromLending(
            msg.sender,
            params.lendingContract,
            params.token,
            params.amount,
            params.minReturn,
            returnedAmount
        );
    }
    /// @dev swap and repay borrow for sender
    function swapAndRepay(ISmartWalletImplementation.SwapAndRepayParams calldata params)
        external
        payable
        override
        nonReentrant
        returns (uint256 destAmount)
    {
        require(params.tradePath.length >= 1, "invalid tradePath");
        require(supportedLendings.contains(params.lendingContract), "unsupported lending");
        // use user debt value if debt is <= payAmount
        // user can pay all debt by putting really high payAmount as param
        uint256 debt = ILending(params.lendingContract).getUserDebtCurrent(
            params.tradePath[params.tradePath.length - 1],
            msg.sender
        );
        uint256 actualPayAmount = debt >= params.payAmount ? params.payAmount : debt;
        if (params.tradePath.length == 1) {
            // just collect src token, no need to swap
            validateSourceAmount(params.tradePath[0], params.srcAmount);
            destAmount = safeTransferWithFee(
                msg.sender,
                params.lendingContract,
                params.tradePath[0],
                params.srcAmount,
                // Not taking repay fee
                0,
                params.platformWallet
            );
        } else {
            destAmount = swapInternal(
                params.swapContract,
                params.srcAmount,
                actualPayAmount,
                params.tradePath,
                params.lendingContract,
                params.feeMode,
                params.feeBps,
                params.platformWallet,
                params.extraArgs
            );
        }
        ILending(params.lendingContract).repayBorrowTo(
            msg.sender,
            IERC20Ext(params.tradePath[params.tradePath.length - 1]),
            destAmount,
            actualPayAmount,
            abi.encodePacked(params.rateMode)
        );
        uint256 actualDebtPaid = debt.sub(
            ILending(params.lendingContract).getUserDebtCurrent(
                params.tradePath[params.tradePath.length - 1],
                msg.sender
            )
        );
        require(actualDebtPaid >= actualPayAmount, "low paid amount");
        emit SwapAndRepay(
            msg.sender,
            params.swapContract,
            params.lendingContract,
            params.tradePath,
            params.srcAmount,
            destAmount,
            actualPayAmount,
            params.feeMode,
            params.feeBps,
            params.platformWallet
        );
    }
    function swapInternal(
        address payable swapContract,
        uint256 srcAmount,
        uint256 minDestAmount,
        address[] calldata tradePath,
        address payable recipient,
        FeeMode feeMode,
        uint256 platformFee,
        address payable platformWallet,
        bytes calldata extraArgs
    ) internal returns (uint256 destAmount) {
        require(supportedSwaps.contains(swapContract), "unsupported swap");
        require(tradePath.length >= 2, "invalid tradePath");
        require(platformFee < BPS, "high platform fee");
        validateSourceAmount(tradePath[0], srcAmount);
        uint256 actualSrcAmount = safeTransferWithFee(
            msg.sender,
            swapContract,
            tradePath[0],
            srcAmount,
            feeMode == FeeMode.FROM_SOURCE ? platformFee : 0,
            platformWallet
        );
        {
            // to avoid stack too deep
            // who will receive the swapped token
            // address _recipient = feeMode == FeeMode.FROM_DEST ? address(this) : recipient;
            uint256 delta = getBalance(IERC20Ext(tradePath[tradePath.length - 1]), feeMode == FeeMode.FROM_DEST ? address(this) : recipient);
            destAmount = ISwap(swapContract).swap(
                ISwap.SwapParams({
                    srcAmount: actualSrcAmount,
                    minDestAmount: minDestAmount,
                    tradePath: tradePath,
                    recipient: feeMode == FeeMode.FROM_DEST ? address(this) : recipient,
                    feeBps: feeMode == FeeMode.BY_PROTOCOL ? platformFee : 0,
                    feeReceiver: platformWallet,
                    extraArgs: extraArgs
                })
            );
            delta = getBalance(IERC20Ext(tradePath[tradePath.length - 1]), feeMode == FeeMode.FROM_DEST ? address(this) : recipient) - delta;
            require(delta >= destAmount, "return amount not enough");
        }
        if (feeMode == FeeMode.FROM_DEST) {
            destAmount = safeTransferWithFee(
                address(this),
                recipient,
                tradePath[tradePath.length - 1],
                destAmount,
                platformFee,
                platformWallet
            );
        }
        require(destAmount >= minDestAmount, "low return");
    }
    function validateSourceAmount(address srcToken, uint256 srcAmount) internal {
        if (srcToken == address(ETH_TOKEN_ADDRESS)) {
            require(msg.value == srcAmount, "wrong msg value");
        } else {
            require(msg.value == 0, "bad msg value");
        }
    }
    function transferToken(
        address payable to,
        IERC20Ext token,
        uint256 amount
    ) internal {
        if (amount == 0) return;
        if (token == ETH_TOKEN_ADDRESS) {
            (bool success, ) = to.call{value: amount}("");
            require(success, "transfer failed");
        } else {
            token.safeTransfer(to, amount);
        }
    }
    function safeTransferWithFee(
        address payable from,
        address payable to,
        address token,
        uint256 amount,
        uint256 platformFeeBps,
        address payable platformWallet
    ) internal returns (uint256 amountTransferred) {
        uint256 fee = amount.mul(platformFeeBps).div(BPS);
        uint256 amountAfterFee = amount.sub(fee);
        IERC20Ext tokenErc = IERC20Ext(token);
        if (tokenErc == ETH_TOKEN_ADDRESS) {
            (bool success, ) = to.call{value: amountAfterFee}("");
            require(success, "transfer failed");
            amountTransferred = amountAfterFee;
        } else {
            uint256 balanceBefore = tokenErc.balanceOf(to);
            if (from != address(this)) {
                // case transfer from another address, need to transfer fee to this proxy contract
                tokenErc.safeTransferFrom(from, to, amountAfterFee);
                if (fee > 0) {
                    tokenErc.safeTransferFrom(from, address(this), fee);
                }
            } else {
                tokenErc.safeTransfer(to, amountAfterFee);
            }
            amountTransferred = tokenErc.balanceOf(to).sub(balanceBefore);
        }
        addFeeToPlatform(platformWallet, tokenErc, fee);
    }
    function addFeeToPlatform(
        address payable platformWallet,
        IERC20Ext token,
        uint256 amount
    ) internal {
        if (amount > 0) {
            require(supportedPlatformWallets.contains(platformWallet), "unsupported platform");
            platformWalletFees[platformWallet][token] = platformWalletFees[platformWallet][token]
            .add(amount);
        }
    }
    function compareStrings(string memory a, string memory b) private pure returns (bool) {
        return (keccak256(abi.encodePacked((a))) == keccak256(abi.encodePacked((b))));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "./IERC20.sol";
import "../../math/SafeMath.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 SafeMath for uint256;
    using Address for address;
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }
    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.
        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.
    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];
        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.
            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;
            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
            bytes32 lastvalue = set._values[lastIndex];
            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based
            // Delete the slot where the moved value was stored
            set._values.pop();
            // Delete the index for the deleted slot
            delete set._indexes[value];
            return true;
        } else {
            return false;
        }
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }
    // Bytes32Set
    struct Bytes32Set {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }
    // AddressSet
    struct AddressSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }
    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }
    // UintSet
    struct UintSet {
        Set _inner;
    }
    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }
    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }
    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }
    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }
   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
/**
 * @dev Interface extending ERC20 standard to include decimals() as
 *      it is optional in the OpenZeppelin IERC20 interface.
 */
interface IERC20Ext is IERC20 {
    /**
     * @dev This function is required as Kyber requires to interact
     *      with token.decimals() with many of its operations.
     */
    function decimals() external view returns (uint8 digits);
}
pragma solidity 0.7.6;
pragma abicoder v2;
import "@kyber.network/utils-sc/contracts/IERC20Ext.sol";
interface ISmartWalletImplementation {
    enum FeeMode {
        FROM_SOURCE,
        FROM_DEST,
        BY_PROTOCOL
    }
    event Swap(
        address indexed trader,
        address indexed swapContract,
        address[] tradePath,
        uint256 srcAmount,
        uint256 destAmount,
        FeeMode feeMode,
        uint256 feeBps,
        address platformWallet
    );
    event SwapAndDeposit(
        address indexed trader,
        address indexed swapContract,
        address indexed lendingContract,
        address[] tradePath,
        uint256 srcAmount,
        uint256 destAmount,
        FeeMode feeMode,
        uint256 feeBps,
        address platformWallet
    );
    event WithdrawFromLending(
        address indexed trader,
        address indexed lendingContract,
        IERC20Ext token,
        uint256 amount,
        uint256 minReturn,
        uint256 actualReturnAmount
    );
    event SwapAndRepay(
        address indexed trader,
        address indexed swapContract,
        address indexed lendingContract,
        address[] tradePath,
        uint256 srcAmount,
        uint256 destAmount,
        uint256 payAmount,
        FeeMode feeMode,
        uint256 feeBps,
        address platformWallet
    );
    /// @param swapContract swap contract
    /// @param srcAmount amount of src token
    /// @param tradePath path of the trade on Uniswap
    /// @param platformFee fee if swapping feeMode = platformFee / BPS, feeBps = platformFee % BPS
    /// @param extraArgs extra data needed for swap on particular platforms
    struct GetExpectedReturnParams {
        address payable swapContract;
        uint256 srcAmount;
        address[] tradePath;
        FeeMode feeMode;
        uint256 feeBps;
        bytes extraArgs;
    }
    function getExpectedReturn(GetExpectedReturnParams calldata params)
        external
        view
        returns (uint256 destAmount, uint256 expectedRate);
    function getExpectedReturnWithImpact(GetExpectedReturnParams calldata params)
        external
        view
        returns (
            uint256 destAmount,
            uint256 expectedRate,
            uint256 priceImpact
        ); // in BPS
    struct GetExpectedInParams {
        address payable swapContract;
        uint256 destAmount;
        address[] tradePath;
        FeeMode feeMode;
        uint256 feeBps;
        bytes extraArgs;
    }
    function getExpectedIn(GetExpectedInParams calldata params)
        external
        view
        returns (uint256 srcAmount, uint256 expectedRate);
    function getExpectedInWithImpact(GetExpectedInParams calldata params)
        external
        view
        returns (
            uint256 srcAmount,
            uint256 expectedRate,
            uint256 priceImpact
        );
    /// @param swapContract swap contract
    /// @param srcAmount amount of src token
    /// @param minDestAmount minimal accepted dest amount
    /// @param tradePath path of the trade on Uniswap
    /// @param feeMode fee mode
    /// @param feeBps fee bps
    /// @param platformWallet wallet to receive fee
    /// @param extraArgs extra data needed for swap on particular platforms
    struct SwapParams {
        address payable swapContract;
        uint256 srcAmount;
        uint256 minDestAmount;
        address[] tradePath;
        FeeMode feeMode;
        uint256 feeBps;
        address payable platformWallet;
        bytes extraArgs;
    }
    function swap(SwapParams calldata params) external payable returns (uint256 destAmount);
    /// @param swapContract swap contract
    /// @param lendingContract lending contract
    /// @param srcAmount amount of src token
    /// @param minDestAmount minimal accepted dest amount
    /// @param tradePath path of the trade on Uniswap
    /// @param feeMode fee mode
    /// @param feeBps fee bps
    /// @param platformWallet wallet to receive fee
    /// @param extraArgs extra data needed for swap on particular platforms
    struct SwapAndDepositParams {
        address payable swapContract;
        address payable lendingContract;
        uint256 srcAmount;
        uint256 minDestAmount;
        address[] tradePath;
        FeeMode feeMode;
        uint256 feeBps;
        address payable platformWallet;
        bytes extraArgs;
    }
    function swapAndDeposit(SwapAndDepositParams calldata params)
        external
        payable
        returns (uint256 destAmount);
    /// @param lendingContract lending contract to withdraw token
    /// @param token underlying token to withdraw, e.g ETH, USDT, DAI
    /// @param amount amount of cToken (COMPOUND) or aToken (AAVE) to withdraw
    /// @param minReturn minimum amount of underlying tokens to return
    struct WithdrawFromLendingPlatformParams {
        address payable lendingContract;
        IERC20Ext token;
        uint256 amount;
        uint256 minReturn;
    }
    function withdrawFromLendingPlatform(WithdrawFromLendingPlatformParams calldata params)
        external
        returns (uint256 returnedAmount);
    /// @param swapContract swap contract
    /// @param lendingContract lending contract
    /// @param srcAmount amount of src token
    /// @param payAmount: amount that user wants to pay, if the dest amount (after swap) is higher,
    ///     the remain amount will be sent back to user's wallet
    /// @param tradePath path of the trade on Uniswap
    /// @param rateMode rate mode for aave v2
    /// @param feeMode fee mode
    /// @param feeBps fee bps
    /// @param platformWallet wallet to receive fee
    /// @param extraArgs extra data needed for swap on particular platforms
    struct SwapAndRepayParams {
        address payable swapContract;
        address payable lendingContract;
        uint256 srcAmount;
        uint256 payAmount;
        address[] tradePath;
        uint256 rateMode; // for aave v2
        FeeMode feeMode;
        uint256 feeBps;
        address payable platformWallet;
        bytes extraArgs;
    }
    function swapAndRepay(SwapAndRepayParams calldata params)
        external
        payable
        returns (uint256 destAmount);
    function claimPlatformFee(IERC20Ext[] calldata tokens) external;
    function adminClaimPlatformFees(
        address[] calldata platformWallets,
        IERC20Ext[] calldata tokens
    ) external;
    function adminClaimPlatformFeesUrgent(
        address[] calldata platformWallets,
        IERC20Ext[] calldata tokens
    ) external;
    function setAdminFeeCollector(address feeCollector) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
import "@kyber.network/utils-sc/contracts/IERC20Ext.sol";
import "@kyber.network/utils-sc/contracts/Utils.sol";
import "@kyber.network/utils-sc/contracts/Withdrawable.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/EnumerableSet.sol";
contract SmartWalletStorage is Utils, Withdrawable, ReentrancyGuard {
    uint256 internal constant MAX_AMOUNT = type(uint256).max;
    mapping(address => mapping(IERC20Ext => uint256)) public platformWalletFees;
    EnumerableSet.AddressSet internal supportedPlatformWallets;
    
    EnumerableSet.AddressSet internal supportedSwaps;
    EnumerableSet.AddressSet internal supportedLendings;
    // [EIP-1967] bytes32(uint256(keccak256("SmartWalletImplementation")) - 1)
    bytes32 internal constant IMPLEMENTATION =
        0x7cf58d76330f82325c2a503c72b55abca3eb533fadde43d95e3c0cceb1583e99;
    constructor(address _admin) Withdrawable(_admin) {}
}
abstract contract SmartWalletStorageV2 is SmartWalletStorage {
    address public adminFeeCollector;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
pragma abicoder v2;
interface ISwap {
    struct GetExpectedReturnParams {
        uint256 srcAmount;
        address[] tradePath;
        uint256 feeBps;
        bytes extraArgs;
    }
    function getExpectedReturn(GetExpectedReturnParams calldata params)
        external
        view
        returns (uint256 destAmount);
    function getExpectedReturnWithImpact(GetExpectedReturnParams calldata params)
        external
        view
        returns (uint256 destAmount, uint256 priceImpact);
    struct GetExpectedInParams {
        uint256 destAmount;
        address[] tradePath;
        uint256 feeBps;
        bytes extraArgs;
    }
    function getExpectedIn(GetExpectedInParams calldata params)
        external
        view
        returns (uint256 srcAmount);
    function getExpectedInWithImpact(GetExpectedInParams calldata params)
        external
        view
        returns (uint256 srcAmount, uint256 priceImpact);
    struct SwapParams {
        uint256 srcAmount;
        uint256 minDestAmount;
        address[] tradePath;
        address recipient;
        uint256 feeBps;
        address payable feeReceiver;
        bytes extraArgs;
    }
    function swap(SwapParams calldata params) external payable returns (uint256 destAmount);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.7.6;
pragma experimental ABIEncoderV2;
import "@kyber.network/utils-sc/contracts/IERC20Ext.sol";
interface ILending {
    function depositTo(
        address payable onBehalfOf,
        IERC20Ext token,
        uint256 amount
    ) external;
    function withdrawFrom(
        address payable onBehalfOf,
        IERC20Ext token,
        uint256 amount,
        uint256 minReturn
    ) external returns (uint256 returnedAmount);
    function repayBorrowTo(
        address payable onBehalfOf,
        IERC20Ext token,
        uint256 amount,
        uint256 payAmount,
        bytes calldata extraArgs // for extra data .i.e aave rateMode
    ) external;
    function getUserDebtCurrent(address _reserve, address _user) external returns (uint256 debt);
    function getLendingToken(IERC20Ext token) external view returns (address);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.
        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }
    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "./IERC20Ext.sol";
/**
 * @title Kyber utility file
 * mostly shared constants and rate calculation helpers
 * inherited by most of kyber contracts.
 * previous utils implementations are for previous solidity versions.
 */
abstract contract Utils {
    // Declared constants below to be used in tandem with
    // getDecimalsConstant(), for gas optimization purposes
    // which return decimals from a constant list of popular
    // tokens.
    IERC20Ext internal constant ETH_TOKEN_ADDRESS = IERC20Ext(
        0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE
    );
    IERC20Ext internal constant USDT_TOKEN_ADDRESS = IERC20Ext(
        0xdAC17F958D2ee523a2206206994597C13D831ec7
    );
    IERC20Ext internal constant DAI_TOKEN_ADDRESS = IERC20Ext(
        0x6B175474E89094C44Da98b954EedeAC495271d0F
    );
    IERC20Ext internal constant USDC_TOKEN_ADDRESS = IERC20Ext(
        0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48
    );
    IERC20Ext internal constant WBTC_TOKEN_ADDRESS = IERC20Ext(
        0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599
    );
    IERC20Ext internal constant KNC_TOKEN_ADDRESS = IERC20Ext(
        0xdd974D5C2e2928deA5F71b9825b8b646686BD200
    );
    uint256 public constant BPS = 10000; // Basic Price Steps. 1 step = 0.01%
    uint256 internal constant PRECISION = (10**18);
    uint256 internal constant MAX_QTY = (10**28); // 10B tokens
    uint256 internal constant MAX_RATE = (PRECISION * 10**7); // up to 10M tokens per eth
    uint256 internal constant MAX_DECIMALS = 18;
    uint256 internal constant ETH_DECIMALS = 18;
    uint256 internal constant MAX_ALLOWANCE = uint256(-1); // token.approve inifinite
    mapping(IERC20Ext => uint256) internal decimals;
    /// @dev Sets the decimals of a token to storage if not already set, and returns
    ///      the decimals value of the token. Prefer using this function over
    ///      getDecimals(), to avoid forgetting to set decimals in local storage.
    /// @param token The token type
    /// @return tokenDecimals The decimals of the token
    function getSetDecimals(IERC20Ext token) internal returns (uint256 tokenDecimals) {
        tokenDecimals = getDecimalsConstant(token);
        if (tokenDecimals > 0) return tokenDecimals;
        tokenDecimals = decimals[token];
        if (tokenDecimals == 0) {
            tokenDecimals = token.decimals();
            decimals[token] = tokenDecimals;
        }
    }
    /// @dev Get the balance of a user
    /// @param token The token type
    /// @param user The user's address
    /// @return The balance
    function getBalance(IERC20Ext token, address user) internal view returns (uint256) {
        if (token == ETH_TOKEN_ADDRESS) {
            return user.balance;
        } else {
            return token.balanceOf(user);
        }
    }
    /// @dev Get the decimals of a token, read from the constant list, storage,
    ///      or from token.decimals(). Prefer using getSetDecimals when possible.
    /// @param token The token type
    /// @return tokenDecimals The decimals of the token
    function getDecimals(IERC20Ext token) internal view returns (uint256 tokenDecimals) {
        // return token decimals if has constant value
        tokenDecimals = getDecimalsConstant(token);
        if (tokenDecimals > 0) return tokenDecimals;
        // handle case where token decimals is not a declared decimal constant
        tokenDecimals = decimals[token];
        // moreover, very possible that old tokens have decimals 0
        // these tokens will just have higher gas fees.
        return (tokenDecimals > 0) ? tokenDecimals : token.decimals();
    }
    function calcDestAmount(
        IERC20Ext src,
        IERC20Ext dest,
        uint256 srcAmount,
        uint256 rate
    ) internal view returns (uint256) {
        return calcDstQty(srcAmount, getDecimals(src), getDecimals(dest), rate);
    }
    function calcSrcAmount(
        IERC20Ext src,
        IERC20Ext dest,
        uint256 destAmount,
        uint256 rate
    ) internal view returns (uint256) {
        return calcSrcQty(destAmount, getDecimals(src), getDecimals(dest), rate);
    }
    function calcDstQty(
        uint256 srcQty,
        uint256 srcDecimals,
        uint256 dstDecimals,
        uint256 rate
    ) internal pure returns (uint256) {
        require(srcQty <= MAX_QTY, "srcQty > MAX_QTY");
        require(rate <= MAX_RATE, "rate > MAX_RATE");
        if (dstDecimals >= srcDecimals) {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            return (srcQty * rate * (10**(dstDecimals - srcDecimals))) / PRECISION;
        } else {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            return (srcQty * rate) / (PRECISION * (10**(srcDecimals - dstDecimals)));
        }
    }
    function calcSrcQty(
        uint256 dstQty,
        uint256 srcDecimals,
        uint256 dstDecimals,
        uint256 rate
    ) internal pure returns (uint256) {
        require(dstQty <= MAX_QTY, "dstQty > MAX_QTY");
        require(rate <= MAX_RATE, "rate > MAX_RATE");
        //source quantity is rounded up. to avoid dest quantity being too low.
        uint256 numerator;
        uint256 denominator;
        if (srcDecimals >= dstDecimals) {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            numerator = (PRECISION * dstQty * (10**(srcDecimals - dstDecimals)));
            denominator = rate;
        } else {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            numerator = (PRECISION * dstQty);
            denominator = (rate * (10**(dstDecimals - srcDecimals)));
        }
        return (numerator + denominator - 1) / denominator; //avoid rounding down errors
    }
    function calcRateFromQty(
        uint256 srcAmount,
        uint256 destAmount,
        uint256 srcDecimals,
        uint256 dstDecimals
    ) internal pure returns (uint256) {
        require(srcAmount <= MAX_QTY, "srcAmount > MAX_QTY");
        require(destAmount <= MAX_QTY, "destAmount > MAX_QTY");
        if (dstDecimals >= srcDecimals) {
            require((dstDecimals - srcDecimals) <= MAX_DECIMALS, "dst - src > MAX_DECIMALS");
            return ((destAmount * PRECISION) / ((10**(dstDecimals - srcDecimals)) * srcAmount));
        } else {
            require((srcDecimals - dstDecimals) <= MAX_DECIMALS, "src - dst > MAX_DECIMALS");
            return ((destAmount * PRECISION * (10**(srcDecimals - dstDecimals))) / srcAmount);
        }
    }
    /// @dev save storage access by declaring token decimal constants
    /// @param token The token type
    /// @return token decimals
    function getDecimalsConstant(IERC20Ext token) internal pure returns (uint256) {
        if (token == ETH_TOKEN_ADDRESS) {
            return ETH_DECIMALS;
        } else if (token == USDT_TOKEN_ADDRESS) {
            return 6;
        } else if (token == DAI_TOKEN_ADDRESS) {
            return 18;
        } else if (token == USDC_TOKEN_ADDRESS) {
            return 6;
        } else if (token == WBTC_TOKEN_ADDRESS) {
            return 8;
        } else if (token == KNC_TOKEN_ADDRESS) {
            return 18;
        } else {
            return 0;
        }
    }
    function minOf(uint256 x, uint256 y) internal pure returns (uint256) {
        return x > y ? y : x;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./IERC20Ext.sol";
import "./PermissionAdmin.sol";
abstract contract Withdrawable is PermissionAdmin {
    using SafeERC20 for IERC20Ext;
    event TokenWithdraw(IERC20Ext token, uint256 amount, address sendTo);
    event EtherWithdraw(uint256 amount, address sendTo);
    constructor(address _admin) PermissionAdmin(_admin) {}
    /**
     * @dev Withdraw all IERC20Ext compatible tokens
     * @param token IERC20Ext The address of the token contract
     */
    function withdrawToken(
        IERC20Ext token,
        uint256 amount,
        address sendTo
    ) external onlyAdmin {
        token.safeTransfer(sendTo, amount);
        emit TokenWithdraw(token, amount, sendTo);
    }
    /**
     * @dev Withdraw Ethers
     */
    function withdrawEther(uint256 amount, address payable sendTo) external onlyAdmin {
        (bool success, ) = sendTo.call{value: amount}("");
        require(success, "withdraw failed");
        emit EtherWithdraw(amount, sendTo);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;
    uint256 private _status;
    constructor () internal {
        _status = _NOT_ENTERED;
    }
    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
abstract contract PermissionAdmin {
    address public admin;
    address public pendingAdmin;
    event AdminClaimed(address newAdmin, address previousAdmin);
    event TransferAdminPending(address pendingAdmin);
    constructor(address _admin) {
        require(_admin != address(0), "admin 0");
        admin = _admin;
    }
    modifier onlyAdmin() {
        require(msg.sender == admin, "only admin");
        _;
    }
    /**
     * @dev Allows the current admin to set the pendingAdmin address.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdmin(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0), "new admin 0");
        emit TransferAdminPending(newAdmin);
        pendingAdmin = newAdmin;
    }
    /**
     * @dev Allows the current admin to set the admin in one tx. Useful initial deployment.
     * @param newAdmin The address to transfer ownership to.
     */
    function transferAdminQuickly(address newAdmin) public onlyAdmin {
        require(newAdmin != address(0), "admin 0");
        emit TransferAdminPending(newAdmin);
        emit AdminClaimed(newAdmin, admin);
        admin = newAdmin;
    }
    /**
     * @dev Allows the pendingAdmin address to finalize the change admin process.
     */
    function claimAdmin() public {
        require(pendingAdmin == msg.sender, "not pending");
        emit AdminClaimed(pendingAdmin, admin);
        admin = pendingAdmin;
        pendingAdmin = address(0);
    }
}