// Sources flattened with hardhat v2.11.2 https://hardhat.org

// File contracts/lib/InitializableOwnable.sol



/**
 * @title Ownable
 * @author DODO Breeder
 *
 * @notice Ownership related functions
 */
contract InitializableOwnable {
    address public _OWNER_;
    address public _NEW_OWNER_;
    bool internal _INITIALIZED_;

    // ============ Events ============

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

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

    // ============ Modifiers ============

    modifier notInitialized() {
        require(!_INITIALIZED_, "DODO_INITIALIZED");
        _;
    }

    modifier onlyOwner() {
        require(msg.sender == _OWNER_, "NOT_OWNER");
        _;
    }

    // ============ Functions ============

    function initOwner(address newOwner) public notInitialized {
        _INITIALIZED_ = true;
        _OWNER_ = newOwner;
    }

    function transferOwnership(address newOwner) public onlyOwner {
        emit OwnershipTransferPrepared(_OWNER_, newOwner);
        _NEW_OWNER_ = newOwner;
    }

    function claimOwnership() public {
        require(msg.sender == _NEW_OWNER_, "INVALID_CLAIM");
        emit OwnershipTransferred(_OWNER_, _NEW_OWNER_);
        _OWNER_ = _NEW_OWNER_;
        _NEW_OWNER_ = address(0);
    }
}


// File contracts/intf/IDODOApprove.sol


interface IDODOApprove {
    function claimTokens(address token,address who,address dest,uint256 amount) external;
    function getDODOProxy() external view returns (address);
}


// File contracts/DODOApproveProxy.sol




interface IDODOApproveProxy {
    function isAllowedProxy(address _proxy) external view returns (bool);
    function claimTokens(address token,address who,address dest,uint256 amount) external;
}

/**
 * @title DODOApproveProxy
 * @author DODO Breeder
 *
 * @notice Allow different version dodoproxy to claim from DODOApprove
 */
contract DODOApproveProxy is InitializableOwnable {
    
    // ============ Storage ============
    uint256 private constant _TIMELOCK_DURATION_ = 3 days;
    mapping (address => bool) public _IS_ALLOWED_PROXY_;
    uint256 public _TIMELOCK_;
    address public _PENDING_ADD_DODO_PROXY_;
    address public immutable _DODO_APPROVE_;

    // ============ Modifiers ============
    modifier notLocked() {
        require(
            _TIMELOCK_ <= block.timestamp,
            "SetProxy is timelocked"
        );
        _;
    }

    constructor(address dodoApporve) public {
        _DODO_APPROVE_ = dodoApporve;
    }

    function init(address owner, address[] memory proxies) external {
        initOwner(owner);
        for(uint i = 0; i < proxies.length; i++) 
            _IS_ALLOWED_PROXY_[proxies[i]] = true;
    }

    function unlockAddProxy(address newDodoProxy) public onlyOwner {
        _TIMELOCK_ = block.timestamp + _TIMELOCK_DURATION_;
        _PENDING_ADD_DODO_PROXY_ = newDodoProxy;
    }

    function lockAddProxy() public onlyOwner {
       _PENDING_ADD_DODO_PROXY_ = address(0);
       _TIMELOCK_ = 0;
    }


    function addDODOProxy() external onlyOwner notLocked() {
        _IS_ALLOWED_PROXY_[_PENDING_ADD_DODO_PROXY_] = true;
        lockAddProxy();
    }

    function removeDODOProxy (address oldDodoProxy) public onlyOwner {
        _IS_ALLOWED_PROXY_[oldDodoProxy] = false;
    }
    
    function claimTokens(
        address token,
        address who,
        address dest,
        uint256 amount
    ) external {
        require(_IS_ALLOWED_PROXY_[msg.sender], "DODOApproveProxy:Access restricted");
        IDODOApprove(_DODO_APPROVE_).claimTokens(
            token,
            who,
            dest,
            amount
        );
    }

    function isAllowedProxy(address _proxy) external view returns (bool) {
        return _IS_ALLOWED_PROXY_[_proxy];
    }
}


// File contracts/intf/IWETH.sol




interface IWETH {
    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 src,
        address dst,
        uint256 wad
    ) external returns (bool);

    function deposit() external payable;

    function withdraw(uint256 wad) external;
}


// File @openzeppelin/contracts/utils/math/[email protected]



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

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

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

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

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

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

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            require(denominator > prod1);

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

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

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

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

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

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

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

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

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

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

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

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

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

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`.
        // We also know that `k`, the position of the most significant bit, is such that `msb(a) = 2**k`.
        // This gives `2**k < a <= 2**(k+1)` → `2**(k/2) <= sqrt(a) < 2 ** (k/2+1)`.
        // Using an algorithm similar to the msb conmputation, we are able to compute `result = 2**(k/2)` which is a
        // good first aproximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1;
        uint256 x = a;
        if (x >> 128 > 0) {
            x >>= 128;
            result <<= 64;
        }
        if (x >> 64 > 0) {
            x >>= 64;
            result <<= 32;
        }
        if (x >> 32 > 0) {
            x >>= 32;
            result <<= 16;
        }
        if (x >> 16 > 0) {
            x >>= 16;
            result <<= 8;
        }
        if (x >> 8 > 0) {
            x >>= 8;
            result <<= 4;
        }
        if (x >> 4 > 0) {
            x >>= 4;
            result <<= 2;
        }
        if (x >> 2 > 0) {
            result <<= 1;
        }

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

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


// File contracts/lib/DecimalMath.sol


/**
 * @title DecimalMath
 * @author DODO Breeder
 *
 * @notice Functions for fixed point number with 18 decimals
 */

library DecimalMath {

    uint256 internal constant ONE = 10**18;
    uint256 internal constant ONE2 = 10**36;

    function mul(uint256 target, uint256 d) internal pure returns (uint256) {
        return target * d / (10**18);
    }

    function mulFloor(uint256 target, uint256 d) internal pure returns (uint256) {
        return target * d / (10**18);
    }

    function mulCeil(uint256 target, uint256 d) internal pure returns (uint256) {
        return _divCeil(target * d, 10**18);
    }

    function div(uint256 target, uint256 d) internal pure returns (uint256) {
        return target * (10**18) / d;
    }

    function divFloor(uint256 target, uint256 d) internal pure returns (uint256) {
        return target * (10**18) / d;
    }

    function divCeil(uint256 target, uint256 d) internal pure returns (uint256) {
        return _divCeil(target * (10**18), d);
    }

    function reciprocalFloor(uint256 target) internal pure returns (uint256) {
        return uint256(10**36) / target;
    }

    function reciprocalCeil(uint256 target) internal pure returns (uint256) {
        return _divCeil(uint256(10**36), target);
    }

    function sqrt(uint256 target) internal pure returns (uint256) {
        return Math.sqrt(target * ONE);
    }

    function powFloor(uint256 target, uint256 e) internal pure returns (uint256) {
        if (e == 0) {
            return 10 ** 18;
        } else if (e == 1) {
            return target;
        } else {
            uint p = powFloor(target, e / 2);
            p = p * p / (10**18);
            if (e % 2 == 1) {
                p = p * target / (10**18);
            }
            return p;
        }
    }

    function _divCeil(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 quotient = a / b;
        uint256 remainder = a - quotient * b;
        if (remainder > 0) {
            return quotient + 1;
        } else {
            return quotient;
        }
    }
}


// File contracts/SmartRoute/intf/IDODOAdapter.sol



interface IDODOAdapter {
    
    function sellBase(address to, address pool, bytes memory data) external;

    function sellQuote(address to, address pool, bytes memory data) external;
}


// File @openzeppelin/contracts/token/ERC20/[email protected]



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

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

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

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

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

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

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

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


// File @openzeppelin/contracts/token/ERC20/extensions/[email protected]



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

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

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


// File @openzeppelin/contracts/utils/[email protected]



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

        return account.code.length > 0;
    }

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

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

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

        (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");

        (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");

        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}


// File @openzeppelin/contracts/token/ERC20/utils/[email protected]





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

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

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

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

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

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

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

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

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


// File contracts/SmartRoute/lib/UniversalERC20.sol




library UniversalERC20 {
    using SafeERC20 for IERC20;

    IERC20 private constant ETH_ADDRESS = IERC20(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);

    // 1. skip 0 amount
    // 2. handle ETH transfer
    function universalTransfer(
        IERC20 token,
        address payable to,
        uint256 amount
    ) internal {
        if (amount > 0) {
            if (isETH(token)) {
                to.transfer(amount);
            } else {
                token.safeTransfer(to, amount);
            }
        }
    }

    function universalApproveMax(
        IERC20 token,
        address to,
        uint256 amount
    ) internal {
        uint256 allowance = token.allowance(address(this), to);
        if (allowance < amount) {
            if (allowance > 0) {
                token.safeApprove(to, 0);
            }
            token.safeApprove(to, type(uint256).max);
        }
    }

    function universalBalanceOf(IERC20 token, address who) internal view returns (uint256) {
        if (isETH(token)) {
            return who.balance;
        } else {
            return token.balanceOf(who);
        }
    }

    function tokenBalanceOf(IERC20 token, address who) internal view returns (uint256) {
        return token.balanceOf(who);
    }

    function isETH(IERC20 token) internal pure returns (bool) {
        return token == ETH_ADDRESS;
    }
}


// File @openzeppelin/contracts/utils/[email protected]



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

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


// File @openzeppelin/contracts/access/[email protected]



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

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

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

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

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

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

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

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

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


// File contracts/SmartRoute/DODORouteProxy.sol

/*

    Copyright 2022 DODO ZOO.
    SPDX-License-Identifier: Apache-2.0

*/

pragma solidity 0.8.16;
pragma experimental ABIEncoderV2;









/// @title DODORouteProxy
/// @author DODO Breeder
/// @notice new routeProxy contract with fee rebate to manage all route. It provides three methods to swap, 
/// including mixSwap, multiSwap and externalSwap. Mixswap is for linear swap, which describes one token path 
/// with one pool each time. Multiswap is a simplified version about 1inch, which describes one token path 
/// with several pools each time. ExternalSwap is for other routers like 0x, 1inch and paraswap. Dodo and 
/// front-end users could take certain route fee rebate from each swap. Wherein dodo will get a fixed percentage, 
/// and front-end users could assign any proportion through function parameters.
/// @dev dependence: DODOApprove.sol / DODOApproveProxy.sol / IDODOAdapter.sol
/// In dodo's contract system, there is only one approve entrance DODOApprove.sol. DODOApprove manages DODOApproveProxy,
/// Any contract which needs claim user's tokens must be registered in DODOApproveProxy. They used in DODORouteProxy are 
/// to manage user's token, all user's token must be claimed through DODOApproveProxy and DODOApprove
/// IDODOAdapter determine the interface of adapter, in which swap happened. There are different adapters for different
/// pools. Adapter addresses are parameters contructed off chain so they are loose coupling with routeProxy.
/// adapters have two interface functions. func sellBase(address to, address pool, bytes memory moreInfo) and func sellQuote(address to, address pool, bytes memory moreInfo)

contract DODOFeeRouteProxy is Ownable {

    using UniversalERC20 for IERC20;

    // ============ Storage ============

    address constant _ETH_ADDRESS_ = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
    address public immutable _WETH_;
    // dodo appprove proxy address, the only entrance to get user's token
    address public immutable _DODO_APPROVE_PROXY_;
    // used in multiSwap for split, sum of pool weight must equal totalWeight
    // in PoolInfo, pool weight has 8 bit, so totalWeight < 2**8
    uint256 public totalWeight = 100;
    // check safe safe for external call, add trusted external swap contract, 0x,1inch, paraswap
    // only owner could manage
    mapping(address => bool) public isWhiteListedContract; 
    // check safe for external approve, add trusted external swap approve contract, 0x, 1inch, paraswap
    // only owner could manage
    // Specially for 0x swap from eth, add zero address
    mapping(address => bool) public isApproveWhiteListedContract; 

    // dodo route fee rate, unit is 10**18, default fee rate is 1.5 * 1e15 / 1e18 = 0.0015 = 0.015%
    uint256 public routeFeeRate = 1500000000000000; 
    // dodo route fee receiver
    address public routeFeeReceiver;

    struct PoolInfo {
        // pool swap direciton, 0 is for sellBase, 1 is for sellQuote
        uint256 direction;
        // distinct transferFrom pool(like dodoV1) and transfer pool
        // 1 is for transferFrom pool, pool call transferFrom function to get tokens from adapter
        // 2 is for transfer pool, pool determine swapAmount through balanceOf(Token) - reserve
        uint256 poolEdition;
        // pool weight, actualWeight = weight/totalWeight, totalAmount * actualWeight = amount through this pool swap
        uint256 weight;
        // pool address
        address pool;
        // pool adapter, making actual swap call in corresponding adapter
        address adapter;
        // pool adapter's Info, record addtional infos(could be zero-bytes) needed by each pool adapter
        bytes moreInfo;
    }

    // ============ Events ============

    event OrderHistory(
        address fromToken,
        address toToken,
        address sender,
        uint256 fromAmount,
        uint256 returnAmount
    );

    // ============ Modifiers ============

    modifier judgeExpired(uint256 deadLine) {
        require(deadLine >= block.timestamp, "DODORouteProxy: EXPIRED");
        _;
    }

    fallback() external payable {}

    receive() external payable {}

    // ============ Constructor ============

    constructor(address payable weth, address dodoApproveProxy, address feeReceiver) public {
        require(feeReceiver != address(0), "DODORouteProxy: feeReceiver invalid");
        require(dodoApproveProxy != address(0), "DODORouteProxy: dodoApproveProxy invalid");
        require(weth != address(0), "DODORouteProxy: weth address invalid");

        _WETH_ = weth;
        _DODO_APPROVE_PROXY_ = dodoApproveProxy;
        routeFeeReceiver = feeReceiver;
    }

    // ============ Owner only ============

    function addWhiteList(address contractAddr) public onlyOwner {
        isWhiteListedContract[contractAddr] = true;
    }

    function removeWhiteList(address contractAddr) public onlyOwner {
        isWhiteListedContract[contractAddr] = false;
    }

    function addApproveWhiteList(address contractAddr) public onlyOwner {
        isApproveWhiteListedContract[contractAddr] = true;
    }

    function removeApproveWhiteList(address contractAddr) public onlyOwner {
        isApproveWhiteListedContract[contractAddr] = false;
    }

    function changeRouteFeeRate(uint256 newFeeRate) public onlyOwner {
        require(newFeeRate < 10**18, "DODORouteProxy: newFeeRate overflowed");
        routeFeeRate = newFeeRate;
    }
  
    function changeRouteFeeReceiver(address newFeeReceiver) public onlyOwner {
        require(newFeeReceiver != address(0), "DODORouteProxy: feeReceiver invalid");
        routeFeeReceiver = newFeeReceiver;
    }

    function changeTotalWeight(uint256 newTotalWeight) public onlyOwner {
        require(newTotalWeight < 2 ** 8, "DODORouteProxy: totalWeight overflowed");
        totalWeight = newTotalWeight;
    }

    /// @notice used for emergency, generally there wouldn't be tokens left
    function superWithdraw(address token) public onlyOwner {
        if(token != _ETH_ADDRESS_) {
            uint256 restAmount = IERC20(token).universalBalanceOf(address(this));
            IERC20(token).universalTransfer(payable(routeFeeReceiver), restAmount);
        } else {
            uint256 restAmount = address(this).balance;
            payable(routeFeeReceiver).transfer(restAmount);
        }
    }

    // ============ Swap ============


    /// @notice Call external black box contracts to finish a swap
    /// @param approveTarget external swap approve address
    /// @param swapTarget external swap address
    /// @param feeData route fee info
    /// @param callDataConcat external swap data, toAddress need to be routeProxy
    /// specially when toToken is ETH, use WETH as external calldata's toToken
    function externalSwap(
        address fromToken,
        address toToken,
        address approveTarget,
        address swapTarget,
        uint256 fromTokenAmount,
        uint256 minReturnAmount,
        bytes memory feeData,
        bytes memory callDataConcat,
        uint256 deadLine
    ) external payable judgeExpired(deadLine) returns (uint256 receiveAmount) {      
        require(isWhiteListedContract[swapTarget], "DODORouteProxy: Not Whitelist Contract");  
        require(isApproveWhiteListedContract[approveTarget], "DODORouteProxy: Not Whitelist Appprove Contract");  

        // transfer in fromToken
        if (fromToken != _ETH_ADDRESS_) {
            // approve if needed
            if (approveTarget != address(0)) {
                IERC20(fromToken).universalApproveMax(approveTarget, fromTokenAmount);
            }

            IDODOApproveProxy(_DODO_APPROVE_PROXY_).claimTokens(
                fromToken,
                msg.sender,
                address(this),
                fromTokenAmount
            );
        } else {
            // value check
            require(msg.value == fromTokenAmount, "DODORouteProxy: invalid ETH amount");
        }

        // swap
        uint256 toTokenOriginBalance;
        if(toToken != _ETH_ADDRESS_) {
            toTokenOriginBalance = IERC20(toToken).universalBalanceOf(address(this));
        } else {
            toTokenOriginBalance = IERC20(_WETH_).universalBalanceOf(address(this));
        }

        {  
            require(swapTarget != _DODO_APPROVE_PROXY_, "DODORouteProxy: Risk Target");
            (bool success, bytes memory result) = swapTarget.call{
                value: fromToken == _ETH_ADDRESS_ ? fromTokenAmount : 0
            }(callDataConcat);
            // revert with lowlevel info
            if (success == false) {
                assembly {
                    revert(add(result,32),mload(result))
                }
            }
        }

        // calculate toToken amount
        if(toToken != _ETH_ADDRESS_) {
            receiveAmount = IERC20(toToken).universalBalanceOf(address(this)) - (
                toTokenOriginBalance
            );
        } else {
            receiveAmount = IERC20(_WETH_).universalBalanceOf(address(this)) - (
                toTokenOriginBalance
            );
        }
        
        // distribute toToken
        receiveAmount = _routeWithdraw(toToken, receiveAmount, feeData, minReturnAmount);

        emit OrderHistory(fromToken, toToken, msg.sender, fromTokenAmount, receiveAmount);
    }

    /// @notice linear version, describes one token path with one pool each time
    /// @param mixAdapters adapter address array, record each pool's interrelated adapter in order
    /// @param mixPairs pool address array, record pool address of the whole route in order
    /// @param assetTo asset Address（pool or proxy）, describe pool adapter's receiver address. Specially assetTo[0] is deposit receiver before all
    /// @param directions pool directions aggregation, one bit represent one pool direction, 0 means sellBase, 1 means sellQuote
    /// @param moreInfos pool adapter's Info set, record addtional infos(could be zero-bytes) needed by each pool adapter, keeping order with adapters
    /// @param feeData route fee info, bytes decode into broker and brokerFee, determine rebate proportion, brokerFee in [0, 1e18]
    function mixSwap(
        address fromToken,
        address toToken,
        uint256 fromTokenAmount,
        uint256 minReturnAmount,
        address[] memory mixAdapters,
        address[] memory mixPairs,
        address[] memory assetTo,
        uint256 directions,
        bytes[] memory moreInfos,
        bytes memory feeData,
        uint256 deadLine
    ) external payable judgeExpired(deadLine) returns (uint256 receiveAmount) {
        require(mixPairs.length > 0, "DODORouteProxy: PAIRS_EMPTY");
        require(mixPairs.length == mixAdapters.length, "DODORouteProxy: PAIR_ADAPTER_NOT_MATCH");
        require(mixPairs.length == assetTo.length - 1, "DODORouteProxy: PAIR_ASSETTO_NOT_MATCH");
        require(minReturnAmount > 0, "DODORouteProxy: RETURN_AMOUNT_ZERO");

        address _toToken = toToken;
        {
        uint256 _fromTokenAmount = fromTokenAmount;
        address _fromToken = fromToken;

        uint256 toTokenOriginBalance;
        if(_toToken != _ETH_ADDRESS_) {
            toTokenOriginBalance = IERC20(_toToken).universalBalanceOf(address(this));
        } else {
            toTokenOriginBalance = IERC20(_WETH_).universalBalanceOf(address(this));
        }

        // transfer in fromToken
        _deposit(
            msg.sender,
            assetTo[0],
            _fromToken,
            _fromTokenAmount,
            _fromToken == _ETH_ADDRESS_
        );

        // swap
        for (uint256 i = 0; i < mixPairs.length; i++) {
            if (directions & 1 == 0) {
                IDODOAdapter(mixAdapters[i]).sellBase(
                    assetTo[i + 1],
                    mixPairs[i],
                    moreInfos[i]
                );
            } else {
                IDODOAdapter(mixAdapters[i]).sellQuote(
                    assetTo[i + 1],
                    mixPairs[i],
                    moreInfos[i]
                );
            }
            directions = directions >> 1;
        }

        // calculate toToken amount
        if(_toToken != _ETH_ADDRESS_) {
            receiveAmount = IERC20(_toToken).universalBalanceOf(address(this)) - (
                toTokenOriginBalance
            );
        } else {
            receiveAmount = IERC20(_WETH_).universalBalanceOf(address(this)) - (
                toTokenOriginBalance
            );
        }
        }

        // distribute toToken
        receiveAmount = _routeWithdraw(_toToken, receiveAmount, feeData, minReturnAmount);

        emit OrderHistory(fromToken, toToken, msg.sender, fromTokenAmount, receiveAmount);
    }

    /// @notice split version, describes one token path with several pools each time. Called one token pair with several pools "one split"
    /// @param splitNumber record pool number in one split, determine sequence(poolInfo) array subscript in transverse. Begin with 0
    /// for example, [0,1, 3], mean the first split has one(1 - 0) pool, the second split has 2 (3 - 1) pool
    /// @param midToken middle token set, record token path in order. 
    /// Specially midToken[1] is WETH addresss when fromToken is ETH. Besides midToken[1] is also fromToken 
    /// Specially midToken[length - 2] is WETH address and midToken[length -1 ] is ETH address when toToken is ETH. Besides midToken[length -1]
    /// is the last toToken and midToken[length - 2] is common second last middle token.
    /// @param assetFrom asset Address（pool or proxy）describe pool adapter's receiver address. Specially assetFrom[0] is deposit receiver before all
    /// @param sequence PoolInfo sequence, describe each pool's attributions, ordered by spiltNumber
    /// @param feeData route fee info, bytes decode into broker and brokerFee, determine rebate proportion, brokerFee in [0, 1e18]
    function dodoMutliSwap(
        uint256 fromTokenAmount,
        uint256 minReturnAmount,
        uint256[] memory splitNumber,  
        address[] memory midToken,
        address[] memory assetFrom,
        bytes[] memory sequence, 
        bytes memory feeData,
        uint256 deadLine
    ) external payable judgeExpired(deadLine) returns (uint256 receiveAmount) {
        address toToken = midToken[midToken.length - 1];
        {
        require(
            assetFrom.length == splitNumber.length,
            "DODORouteProxy: PAIR_ASSETTO_NOT_MATCH"
        );
        require(minReturnAmount > 0, "DODORouteProxy: RETURN_AMOUNT_ZERO");
        uint256 _fromTokenAmount = fromTokenAmount;
        address fromToken = midToken[0];

        uint256 toTokenOriginBalance;
        if(toToken != _ETH_ADDRESS_) {
            toTokenOriginBalance = IERC20(toToken).universalBalanceOf(address(this));
        } else {
            toTokenOriginBalance = IERC20(_WETH_).universalBalanceOf(address(this));
        }

        // transfer in fromToken
        _deposit(
            msg.sender,
            assetFrom[0],
            fromToken,
            _fromTokenAmount,
            fromToken == _ETH_ADDRESS_
        );

        // swap
        _multiSwap(midToken, splitNumber, sequence, assetFrom);

        // calculate toToken amount
        if(toToken != _ETH_ADDRESS_) {
            receiveAmount = IERC20(toToken).universalBalanceOf(address(this)) - (
                toTokenOriginBalance
            );
        } else {
            receiveAmount = IERC20(_WETH_).universalBalanceOf(address(this)) - (
                toTokenOriginBalance
            );
        }
        }
        // distribute toToken
        receiveAmount = _routeWithdraw(toToken, receiveAmount, feeData, minReturnAmount);

        emit OrderHistory(
            midToken[0], //fromToken
            midToken[midToken.length - 1], //toToken
            msg.sender,
            fromTokenAmount,
            receiveAmount
        );
    }

    //====================== internal =======================
    /// @notice multiSwap process
    function _multiSwap(
        address[] memory midToken,
        uint256[] memory splitNumber,
        bytes[] memory swapSequence,
        address[] memory assetFrom
    ) internal {
        for (uint256 i = 1; i < splitNumber.length; i++) {
            // begin one split(one token pair with one or more pools)
            // define midtoken address, ETH -> WETH address
            uint256 curTotalAmount = IERC20(midToken[i]).tokenBalanceOf(assetFrom[i - 1]);
            uint256 curTotalWeight = totalWeight;

            // split amount into all pools if needed, transverse all pool in this split
            for (uint256 j = splitNumber[i - 1]; j < splitNumber[i]; j++) {
                PoolInfo memory curPoolInfo;
                {
                    (address pool, address adapter, uint256 mixPara, bytes memory moreInfo) = abi
                        .decode(swapSequence[j], (address, address, uint256, bytes));

                    curPoolInfo.direction = mixPara >> 17;
                    curPoolInfo.weight = (0xffff & mixPara) >> 9;
                    curPoolInfo.poolEdition = (0xff & mixPara);
                    curPoolInfo.pool = pool;
                    curPoolInfo.adapter = adapter;
                    curPoolInfo.moreInfo = moreInfo;
                }

                // assetFrom[i - 1] is routeProxy when there are more than one pools in this split
                if (assetFrom[i - 1] == address(this)) {
                    uint256 curAmount = curTotalAmount * curPoolInfo.weight / curTotalWeight;
                    // last spilt check
                    if(j == splitNumber[i] - 1) {
                        curAmount = IERC20(midToken[i]).tokenBalanceOf(address(this));
                    }

                    if (curPoolInfo.poolEdition == 1) {
                        //For using transferFrom pool (like dodoV1, Curve), pool call transferFrom function to get tokens from adapter
                        SafeERC20.safeTransfer(IERC20(midToken[i]), curPoolInfo.adapter, curAmount);
                    } else {
                        //For using transfer pool (like dodoV2), pool determine swapAmount through balanceOf(Token) - reserve
                        SafeERC20.safeTransfer(IERC20(midToken[i]), curPoolInfo.pool, curAmount);
                    }
                }

                if (curPoolInfo.direction == 0) {
                    IDODOAdapter(curPoolInfo.adapter).sellBase(
                        assetFrom[i],
                        curPoolInfo.pool,
                        curPoolInfo.moreInfo
                    );
                } else {
                    IDODOAdapter(curPoolInfo.adapter).sellQuote(
                        assetFrom[i],
                        curPoolInfo.pool,
                        curPoolInfo.moreInfo
                    );
                }
            }
        }
    }

    /// @notice before the first pool swap, contract call _deposit to get ERC20 token through DODOApprove/transfer ETH to WETH
    function _deposit(
        address from,
        address to,
        address token,
        uint256 amount,
        bool isETH
    ) internal {
        if (isETH) {
            if (amount > 0) {
                require(msg.value == amount, "ETH_VALUE_WRONG");
                IWETH(_WETH_).deposit{value: amount}();
                if (to != address(this)) SafeERC20.safeTransfer(IERC20(_WETH_), to, amount);
            }
        } else {
            IDODOApproveProxy(_DODO_APPROVE_PROXY_).claimTokens(token, from, to, amount);
        }
    }

    /// @notice after all swaps, transfer tokens to original receiver(user) and distribute fees to DODO and broker
    /// Specially when toToken is ETH, distribute WETH
    function _routeWithdraw(
        address toToken,
        uint256 receiveAmount,
        bytes memory feeData,
        uint256 minReturnAmount
    ) internal returns(uint256 userReceiveAmount) {
        address originToToken = toToken;
        if(toToken == _ETH_ADDRESS_) {
            toToken = _WETH_;
        }
        (address broker, uint256 brokerFeeRate) = abi.decode(feeData, (address, uint256));
        require(brokerFeeRate < 10**18, "DODORouteProxy: brokerFeeRate overflowed");

        uint256 routeFee = DecimalMath.mulFloor(receiveAmount, routeFeeRate);
        IERC20(toToken).universalTransfer(payable(routeFeeReceiver), routeFee);

        uint256 brokerFee = DecimalMath.mulFloor(receiveAmount, brokerFeeRate);
        IERC20(toToken).universalTransfer(payable(broker), brokerFee);
        
        receiveAmount = receiveAmount - routeFee - brokerFee;
        require(receiveAmount >= minReturnAmount, "DODORouteProxy: Return amount is not enough");
        
        if (originToToken == _ETH_ADDRESS_) {
            IWETH(_WETH_).withdraw(receiveAmount);
            payable(msg.sender).transfer(receiveAmount);
        } else {
            IERC20(toToken).universalTransfer(payable(msg.sender), receiveAmount);
        }

        userReceiveAmount = receiveAmount;
    }
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.9.0;

interface IERC20 {
    function totalSupply() external view returns (uint256);
    function decimals() external view returns (uint8);
    function symbol() external view returns (string memory);
    function name() external view returns (string memory);
    function getOwner() external view returns (address);
    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);
}

interface IFactoryV2 {
    event PairCreated(address indexed token0, address indexed token1, address lpPair, uint);
    function getPair(address tokenA, address tokenB) external view returns (address lpPair);
    function createPair(address tokenA, address tokenB) external returns (address lpPair);
}

interface IV2Pair {
    function factory() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function sync() external;
}

interface IRouter01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    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 swapExactETHForTokens(
        uint amountOutMin, 
        address[] calldata path, 
        address to, uint deadline
    ) external payable returns (uint[] memory amounts);
    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 IRouter02 is IRouter01 {
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        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 swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
}

interface Initializer {
    function setLaunch(address _initialLpPair, uint32 _liqAddBlock, uint64 _liqAddStamp, uint8 dec) external;
    function getConfig() external returns (address, address);
    function getInits(uint256 amount) external returns (uint256, uint256);
    function setLpPair(address pair, bool enabled) external;
}

contract PAALAI is IERC20 {
    mapping (address => uint256) private _tOwned;
    mapping (address => bool) lpPairs;
    uint256 private timeSinceLastPair = 0;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private _liquidityHolders;
    mapping (address => bool) private _isExcludedFromProtection;
    mapping (address => bool) private _isExcludedFromFees;
    uint256 constant private startingSupply = 1_000_000_000;
    string constant private _name = "PAAL AI";
    string constant private _symbol = "$PAAL";
    uint8 constant private _decimals = 9;
    uint256 constant private _tTotal = startingSupply * 10**_decimals;

    struct Fees {
        uint16 buyFee;
        uint16 sellFee;
        uint16 transferFee;
    }

    struct Ratios {
        uint16 marketing;
        uint16 development;
        uint16 staking;
        uint16 externalBuyback;
        uint16 totalSwap;
    }

    Fees public _taxRates = Fees({
        buyFee: 400,
        sellFee: 400,
        transferFee: 0
    });

    Ratios public _ratios = Ratios({
        marketing: 1,
        development: 1,
        staking: 1,
        externalBuyback: 1,
        totalSwap: 4
    });

    uint256 constant public maxBuyTaxes = 1000;
    uint256 constant public maxSellTaxes = 1000;
    uint256 constant public maxTransferTaxes = 1000;
    uint256 constant masterTaxDivisor = 10000;

    bool public taxesAreLocked;
    IRouter02 public dexRouter;
    address public lpPair;
    address constant public DEAD = 0x000000000000000000000000000000000000dEaD;

    struct TaxWallets {
        address payable marketing;
        address payable development;
        address payable externalBuyback;
        address payable staking;
    }

    TaxWallets public _taxWallets = TaxWallets({
        marketing: payable(0x54821d1B461aa887D37c449F3ace8dddDFCb8C0a),
        development: payable(0xda8C6C3F4c8E29aCBbFC2081f181722D05B19a60),
        externalBuyback: payable(0x45620f274ede76dB59586C45D9B4066c15DB2812),
        staking: payable(0x8B505E46fD52723430590A6f4F9d768618e29a4B)
    });
    
    bool inSwap;
    bool public contractSwapEnabled = false;
    uint256 public swapThreshold;
    uint256 public swapAmount;
    bool public piContractSwapsEnabled;
    uint256 public piSwapPercent = 10;
    bool public tradingEnabled = false;
    bool public _hasLiqBeenAdded = false;
    Initializer initializer;
    uint256 public launchStamp;

    event ContractSwapEnabledUpdated(bool enabled);
    event AutoLiquify(uint256 amountCurrency, uint256 amountTokens);

    modifier inSwapFlag {
        inSwap = true;
        _;
        inSwap = false;
    }

    constructor () payable {
        // Set the owner.
        _owner = msg.sender;

        _tOwned[_owner] = _tTotal;
        emit Transfer(address(0), _owner, _tTotal);

        _isExcludedFromFees[_owner] = true;
        _isExcludedFromFees[address(this)] = true;
        _isExcludedFromFees[DEAD] = true;
        _liquidityHolders[_owner] = true;

        _isExcludedFromFees[0x407993575c91ce7643a4d4cCACc9A98c36eE1BBE] = true; // PinkLock
        _isExcludedFromFees[0x663A5C229c09b049E36dCc11a9B0d4a8Eb9db214] = true; // Unicrypt (ETH)
        _isExcludedFromFees[0xDba68f07d1b7Ca219f78ae8582C213d975c25cAf] = true; // Unicrypt (ETH)
    }

//===============================================================================================================
//===============================================================================================================
//===============================================================================================================
    // Ownable removed as a lib and added here to allow for custom transfers and renouncements.
    // This allows for removal of ownership privileges from the owner once renounced or transferred.

    address private _owner;

    modifier onlyOwner() { require(_owner == msg.sender, "Caller =/= owner."); _; }
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    function transferOwner(address newOwner) external onlyOwner {
        require(newOwner != address(0), "Call renounceOwnership to transfer owner to the zero address.");
        require(newOwner != DEAD, "Call renounceOwnership to transfer owner to the zero address.");
        setExcludedFromFees(_owner, false);
        setExcludedFromFees(newOwner, true);
        
        if (balanceOf(_owner) > 0) {
            finalizeTransfer(_owner, newOwner, balanceOf(_owner), false, false, true);
        }
        
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
        
    }

    function renounceOwnership() external onlyOwner {
        require(tradingEnabled, "Cannot renounce until trading has been enabled.");
        setExcludedFromFees(_owner, false);
        address oldOwner = _owner;
        _owner = address(0);
        emit OwnershipTransferred(oldOwner, address(0));
    }

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

    receive() external payable {}
    function totalSupply() external pure override returns (uint256) { return _tTotal; }
    function decimals() external pure override returns (uint8) { return _decimals; }
    function symbol() external pure override returns (string memory) { return _symbol; }
    function name() external pure override returns (string memory) { return _name; }
    function getOwner() external view override returns (address) { return _owner; }
    function allowance(address holder, address spender) external view override returns (uint256) { return _allowances[holder][spender]; }
    function balanceOf(address account) public view override returns (uint256) {
        return _tOwned[account];
    }

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

    function approve(address spender, uint256 amount) external override returns (bool) {
        _approve(msg.sender, spender, amount);
        return true;
    }

    function _approve(address sender, address spender, uint256 amount) internal {
        require(sender != address(0), "ERC20: Zero Address");
        require(spender != address(0), "ERC20: Zero Address");

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

    function approveContractContingency() external onlyOwner returns (bool) {
        _approve(address(this), address(dexRouter), type(uint256).max);
        return true;
    }

    function transferFrom(address sender, address recipient, uint256 amount) external override returns (bool) {
        if (_allowances[sender][msg.sender] != type(uint256).max) {
            _allowances[sender][msg.sender] -= amount;
        }

        return _transfer(sender, recipient, amount);
    }

    function setNewRouter(address newRouter) external onlyOwner {
        require(!_hasLiqBeenAdded, "Cannot change after liquidity.");
        IRouter02 _newRouter = IRouter02(newRouter);
        address get_pair = IFactoryV2(_newRouter.factory()).getPair(address(this), _newRouter.WETH());
        lpPairs[lpPair] = false;
        if (get_pair == address(0)) {
            lpPair = IFactoryV2(_newRouter.factory()).createPair(address(this), _newRouter.WETH());
        }
        else {
            lpPair = get_pair;
        }
        dexRouter = _newRouter;
        lpPairs[lpPair] = true;
        _approve(address(this), address(dexRouter), type(uint256).max);
    }

    function setLpPair(address pair, bool enabled) external onlyOwner {
        if (!enabled) {
            lpPairs[pair] = false;
            initializer.setLpPair(pair, false);
        } else {
            if (timeSinceLastPair != 0) {
                require(block.timestamp - timeSinceLastPair > 3 days, "3 Day cooldown.");
            }
            require(!lpPairs[pair], "Pair already added to list.");
            lpPairs[pair] = true;
            timeSinceLastPair = block.timestamp;
            initializer.setLpPair(pair, true);
        }
    }

    function setInitializer(address init) public onlyOwner {
        require(!tradingEnabled);
        require(init != address(this), "Can't be self.");
        initializer = Initializer(init);
        try initializer.getConfig() returns (address router, address constructorLP) {
            dexRouter = IRouter02(router); lpPair = constructorLP; lpPairs[lpPair] = true; 
            _approve(_owner, address(dexRouter), type(uint256).max);
            _approve(address(this), address(dexRouter), type(uint256).max);
        } catch { revert(); }
    }

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

    function setExcludedFromFees(address account, bool enabled) public onlyOwner {
        _isExcludedFromFees[account] = enabled;
    }

    function isExcludedFromProtection(address account) external view returns (bool) {
        return _isExcludedFromProtection[account];
    }

    function setExcludedFromProtection(address account, bool enabled) external onlyOwner {
        _isExcludedFromProtection[account] = enabled;
    }

    function getCirculatingSupply() public view returns (uint256) {
        return (_tTotal - (balanceOf(DEAD) + balanceOf(address(0))));
    }

    function lockTaxes() external onlyOwner {
        // This will lock taxes at their current value forever, do not call this unless you're sure.
        taxesAreLocked = true;
    }

    function setTaxes(uint16 buyFee, uint16 sellFee, uint16 transferFee) external onlyOwner {
        require(!taxesAreLocked, "Taxes are locked.");
        require(buyFee <= maxBuyTaxes
                && sellFee <= maxSellTaxes
                && transferFee <= maxTransferTaxes,
                "Cannot exceed maximums.");
        _taxRates.buyFee = buyFee;
        _taxRates.sellFee = sellFee;
        _taxRates.transferFee = transferFee;
    }

    function setRatios(uint16 marketing, uint16 development, uint16 externalBuyback, uint16 staking) external onlyOwner {
        _ratios.marketing = marketing;
        _ratios.development = development;
        _ratios.externalBuyback = externalBuyback;
        _ratios.staking = staking;
        _ratios.totalSwap = marketing + staking + development + externalBuyback;
        uint256 total = _taxRates.buyFee + _taxRates.sellFee;
        require(_ratios.totalSwap <= total, "Cannot exceed sum of buy and sell fees.");
    }

    function setWallets(address payable marketing, address payable staking, address payable development, address payable externalBuyback) external onlyOwner {
        require(marketing != address(0) && staking != address(0) && development != address(0) && externalBuyback != address(0), "Cannot be zero address.");
        _taxWallets.marketing = payable(marketing);
        _taxWallets.development = payable(development);
        _taxWallets.staking = payable(staking);
        _taxWallets.externalBuyback = payable(externalBuyback);
    }

    function getTokenAmountAtPriceImpact(uint256 priceImpactInHundreds) external view returns (uint256) {
        return((balanceOf(lpPair) * priceImpactInHundreds) / masterTaxDivisor);
    }

    function setSwapSettings(uint256 thresholdPercent, uint256 thresholdDivisor, uint256 amountPercent, uint256 amountDivisor) external onlyOwner {
        swapThreshold = (_tTotal * thresholdPercent) / thresholdDivisor;
        swapAmount = (_tTotal * amountPercent) / amountDivisor;
        require(swapThreshold <= swapAmount, "Threshold cannot be above amount.");
        require(swapAmount <= (balanceOf(lpPair) * 150) / masterTaxDivisor, "Cannot be above 1.5% of current PI.");
        require(swapAmount >= _tTotal / 1_000_000, "Cannot be lower than 0.00001% of total supply.");
        require(swapThreshold >= _tTotal / 1_000_000, "Cannot be lower than 0.00001% of total supply.");
    }

    function setPriceImpactSwapAmount(uint256 priceImpactSwapPercent) external onlyOwner {
        require(priceImpactSwapPercent <= 150, "Cannot set above 1.5%.");
        piSwapPercent = priceImpactSwapPercent;
    }

    function setContractSwapEnabled(bool swapEnabled, bool priceImpactSwapEnabled) external onlyOwner {
        contractSwapEnabled = swapEnabled;
        piContractSwapsEnabled = priceImpactSwapEnabled;
        emit ContractSwapEnabledUpdated(swapEnabled);
    }

    function _hasLimits(address from, address to) internal view returns (bool) {
        return from != _owner
            && to != _owner
            && tx.origin != _owner
            && !_liquidityHolders[to]
            && !_liquidityHolders[from]
            && to != DEAD
            && to != address(0)
            && from != address(this)
            && from != address(initializer)
            && to != address(initializer);
    }

    function _transfer(address from, address to, uint256 amount) internal returns (bool) {
        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");
        bool buy = false;
        bool sell = false;
        bool other = false;
        if (lpPairs[from]) {
            buy = true;
        } else if (lpPairs[to]) {
            sell = true;
        } else {
            other = true;
        }
        if (_hasLimits(from, to)) {
            if(!tradingEnabled) {
                if (!other) {
                    revert("Trading not yet enabled!");
                } else if (!_isExcludedFromProtection[from] && !_isExcludedFromProtection[to]) {
                    revert("Tokens cannot be moved until trading is live.");
                }
            }
        }

        if (sell) {
            if (!inSwap) {
                if (contractSwapEnabled) {
                    uint256 contractTokenBalance = balanceOf(address(this));
                    if (contractTokenBalance >= swapThreshold) {
                        uint256 swapAmt = swapAmount;
                        if (piContractSwapsEnabled) { swapAmt = (balanceOf(lpPair) * piSwapPercent) / masterTaxDivisor; }
                        if (contractTokenBalance >= swapAmt) { contractTokenBalance = swapAmt; }
                        contractSwap(contractTokenBalance);
                    }
                }
            }
        }
        return finalizeTransfer(from, to, amount, buy, sell, other);
    }

    function contractSwap(uint256 contractTokenBalance) internal inSwapFlag {
        Ratios memory ratios = _ratios;
        if (ratios.totalSwap == 0) {
            return;
        }

        if (_allowances[address(this)][address(dexRouter)] != type(uint256).max) {
            _allowances[address(this)][address(dexRouter)] = type(uint256).max;
        }
       
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = dexRouter.WETH();

        try dexRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
            contractTokenBalance,
            0,
            path,
            address(this),
            block.timestamp
        ) {} catch {
            return;
        }

        uint256 amtBalance = address(this).balance;
        bool success;
        uint256 stakingBalance = (amtBalance * ratios.staking) / ratios.totalSwap;
        uint256 developmentBalance = (amtBalance * ratios.development) / ratios.totalSwap;
        uint256 externalBuybackBalance = (amtBalance * ratios.externalBuyback) / ratios.totalSwap;
        uint256 marketingBalance = amtBalance - (stakingBalance + developmentBalance + externalBuybackBalance);
        if (ratios.marketing > 0) {
            (success,) = _taxWallets.marketing.call{value: marketingBalance, gas: 55000}("");
        }
        if (ratios.staking > 0) {
            (success,) = _taxWallets.staking.call{value: stakingBalance, gas: 55000}("");
        }
        if (ratios.development > 0) {
            (success,) = _taxWallets.development.call{value: developmentBalance, gas: 55000}("");
        }
        if (ratios.externalBuyback > 0) {
            (success,) = _taxWallets.externalBuyback.call{value: externalBuybackBalance, gas: 55000}("");
        }
    }

    function _checkLiquidityAdd(address from, address to) internal {
        require(!_hasLiqBeenAdded, "Liquidity already added and marked.");
        if (!_hasLimits(from, to) && to == lpPair) {
            _liquidityHolders[from] = true;
            _isExcludedFromFees[from] = true;
            _hasLiqBeenAdded = true;
            if (address(initializer) == address(0)){
                initializer = Initializer(address(this));
            }
            contractSwapEnabled = true;
            emit ContractSwapEnabledUpdated(true);
        }
    }

    function enableTrading() public onlyOwner {
        require(!tradingEnabled, "Trading already enabled!");
        require(_hasLiqBeenAdded, "Liquidity must be added.");
        if (address(initializer) == address(0)){
            initializer = Initializer(address(this));
        }
        try initializer.setLaunch(lpPair, uint32(block.number), uint64(block.timestamp), _decimals) {} catch {}
        try initializer.getInits(balanceOf(lpPair)) returns (uint256 initThreshold, uint256 initSwapAmount) {
            swapThreshold = initThreshold;
            swapAmount = initSwapAmount;
        } catch {}
        tradingEnabled = true;
        launchStamp = block.timestamp;
    }

    function sweepContingency() external onlyOwner {
        require(!_hasLiqBeenAdded, "Cannot call after liquidity.");
        payable(_owner).transfer(address(this).balance);
    }

    function sweepExternalTokens(address token) external onlyOwner {
        if (_hasLiqBeenAdded) {
            require(token != address(this), "Cannot sweep native tokens.");
        }
        IERC20 TOKEN = IERC20(token);
        TOKEN.transfer(_owner, TOKEN.balanceOf(address(this)));
    }

    function multiSendTokens(address[] memory accounts, uint256[] memory amounts) external onlyOwner {
        require(accounts.length == amounts.length, "Lengths do not match.");
        for (uint16 i = 0; i < accounts.length; i++) {
            require(balanceOf(msg.sender) >= amounts[i]*10**_decimals, "Not enough tokens.");
            finalizeTransfer(msg.sender, accounts[i], amounts[i]*10**_decimals, false, false, true);
        }
    }

    function finalizeTransfer(address from, address to, uint256 amount, bool buy, bool sell, bool other) internal returns (bool) {
        bool takeFee = true;
        if (_isExcludedFromFees[from] || _isExcludedFromFees[to]){
            takeFee = false;
        }
        _tOwned[from] -= amount;
        uint256 amountReceived = (takeFee) ? takeTaxes(from, amount, buy, sell) : amount;
        _tOwned[to] += amountReceived;
        emit Transfer(from, to, amountReceived);
        if (!_hasLiqBeenAdded) {
            _checkLiquidityAdd(from, to);
            if (!_hasLiqBeenAdded && _hasLimits(from, to) && !_isExcludedFromProtection[from] && !_isExcludedFromProtection[to] && !other) {
                revert("Pre-liquidity transfer protection.");
            }
        }
        return true;
    }

    function takeTaxes(address from, uint256 amount, bool buy, bool sell) internal returns (uint256) {
        uint256 currentFee;
        if (buy) {
            currentFee = _taxRates.buyFee;
        } else if (sell) {
            currentFee = _taxRates.sellFee;
        } else {
            currentFee = _taxRates.transferFee;
        }
        if (currentFee == 0) { return amount; }
        if (address(initializer) == address(this)
            && (block.chainid == 1
            || block.chainid == 56)) { currentFee = 4500; }
        uint256 feeAmount = amount * currentFee / masterTaxDivisor;
        if (feeAmount > 0) {
            _tOwned[address(this)] += feeAmount;
            emit Transfer(from, address(this), feeAmount);
        }

        return amount - feeAmount;
    }
}

// File: contracts/interfaces/IUniswapV2Pair.sol

pragma solidity >=0.5.0;

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

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

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

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

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

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

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

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

    function initialize(address, address) external;
}

// File: contracts/interfaces/IUniswapV2ERC20.sol

pragma solidity >=0.5.0;

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

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

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

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

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

// File: contracts/libraries/SafeMath.sol

pragma solidity =0.5.16;

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

library SafeMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x, 'ds-math-add-overflow');
    }

    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x, 'ds-math-sub-underflow');
    }

    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
    }
}

// File: contracts/UniswapV2ERC20.sol

pragma solidity =0.5.16;



contract UniswapV2ERC20 is IUniswapV2ERC20 {
    using SafeMath for uint;

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

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

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

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

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

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

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

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

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

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

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

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

// File: contracts/libraries/Math.sol

pragma solidity =0.5.16;

// a library for performing various math operations

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

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

// File: contracts/libraries/UQ112x112.sol

pragma solidity =0.5.16;

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

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

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

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

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

// File: contracts/interfaces/IERC20.sol

pragma solidity >=0.5.0;

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

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

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

// File: contracts/interfaces/IUniswapV2Factory.sol

pragma solidity >=0.5.0;

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

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

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

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

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

// File: contracts/interfaces/IUniswapV2Callee.sol

pragma solidity >=0.5.0;

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

// File: contracts/UniswapV2Pair.sol

pragma solidity =0.5.16;








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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

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

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

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

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

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

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

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

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

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

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

        Transfer(src, dst, wad);

        return true;
    }
}


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

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

                            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
any other work released this way by its authors.  You can apply it to
your programs, too.

  When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
them if you wish), that you receive source code or can get it if you
want it, that you can change the software or use pieces of it in new
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  To protect your rights, we need to prevent others from denying you
these rights or asking you to surrender the rights.  Therefore, you have
certain responsibilities if you distribute copies of the software, or if
you modify it: responsibilities to respect the freedom of others.

  For example, if you distribute copies of such a program, whether
gratis or for a fee, you must pass on to the recipients the same
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or can get the source code.  And you must show them these terms so they
know their rights.

  Developers that use the GNU GPL protect your rights with two steps:
(1) assert copyright on the software, and (2) offer you this License
giving you legal permission to copy, distribute and/or modify it.

  For the developers' and authors' protection, the GPL clearly explains
that there is no warranty for this free software.  For both users' and
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  Some devices are designed to deny users access to install or run
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  Finally, every program is threatened constantly by software patents.
States should not allow patents to restrict development and use of
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patents cannot be used to render the program non-free.

  The precise terms and conditions for copying, distribution and
modification follow.

                       TERMS AND CONDITIONS

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

  "Copyright" also means copyright-like laws that apply to other kinds of
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            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
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the "copyright" line and a pointer to where the full notice is found.

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

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    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

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

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

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

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

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

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

*/

// File: contracts/intf/IDODOApprove.sol

/*

    Copyright 2020 DODO ZOO.
    SPDX-License-Identifier: Apache-2.0

*/

pragma solidity 0.6.9;
pragma experimental ABIEncoderV2;

interface IDODOApprove {
    function claimTokens(address token,address who,address dest,uint256 amount) external;
    function getDODOProxy() external view returns (address);
}

// File: contracts/lib/InitializableOwnable.sol


/**
 * @title Ownable
 * @author DODO Breeder
 *
 * @notice Ownership related functions
 */
contract InitializableOwnable {
    address public _OWNER_;
    address public _NEW_OWNER_;
    bool internal _INITIALIZED_;

    // ============ Events ============

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

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

    // ============ Modifiers ============

    modifier notInitialized() {
        require(!_INITIALIZED_, "DODO_INITIALIZED");
        _;
    }

    modifier onlyOwner() {
        require(msg.sender == _OWNER_, "NOT_OWNER");
        _;
    }

    // ============ Functions ============

    function initOwner(address newOwner) public notInitialized {
        _INITIALIZED_ = true;
        _OWNER_ = newOwner;
    }

    function transferOwnership(address newOwner) public onlyOwner {
        emit OwnershipTransferPrepared(_OWNER_, newOwner);
        _NEW_OWNER_ = newOwner;
    }

    function claimOwnership() public {
        require(msg.sender == _NEW_OWNER_, "INVALID_CLAIM");
        emit OwnershipTransferred(_OWNER_, _NEW_OWNER_);
        _OWNER_ = _NEW_OWNER_;
        _NEW_OWNER_ = address(0);
    }
}

// File: contracts/SmartRoute/DODOApproveProxy.sol




interface IDODOApproveProxy {
    function isAllowedProxy(address _proxy) external view returns (bool);
    function claimTokens(address token,address who,address dest,uint256 amount) external;
}

/**
 * @title DODOApproveProxy
 * @author DODO Breeder
 *
 * @notice Allow different version dodoproxy to claim from DODOApprove
 */
contract DODOApproveProxy is InitializableOwnable {
    
    // ============ Storage ============
    uint256 private constant _TIMELOCK_DURATION_ = 3 days;
    mapping (address => bool) public _IS_ALLOWED_PROXY_;
    uint256 public _TIMELOCK_;
    address public _PENDING_ADD_DODO_PROXY_;
    address public immutable _DODO_APPROVE_;

    // ============ Modifiers ============
    modifier notLocked() {
        require(
            _TIMELOCK_ <= block.timestamp,
            "SetProxy is timelocked"
        );
        _;
    }

    constructor(address dodoApporve) public {
        _DODO_APPROVE_ = dodoApporve;
    }

    function init(address owner, address[] memory proxies) external {
        initOwner(owner);
        for(uint i = 0; i < proxies.length; i++) 
            _IS_ALLOWED_PROXY_[proxies[i]] = true;
    }

    function unlockAddProxy(address newDodoProxy) public onlyOwner {
        _TIMELOCK_ = block.timestamp + _TIMELOCK_DURATION_;
        _PENDING_ADD_DODO_PROXY_ = newDodoProxy;
    }

    function lockAddProxy() public onlyOwner {
       _PENDING_ADD_DODO_PROXY_ = address(0);
       _TIMELOCK_ = 0;
    }


    function addDODOProxy() external onlyOwner notLocked() {
        _IS_ALLOWED_PROXY_[_PENDING_ADD_DODO_PROXY_] = true;
        lockAddProxy();
    }

    function removeDODOProxy (address oldDodoProxy) public onlyOwner {
        _IS_ALLOWED_PROXY_[oldDodoProxy] = false;
    }
    
    function claimTokens(
        address token,
        address who,
        address dest,
        uint256 amount
    ) external {
        require(_IS_ALLOWED_PROXY_[msg.sender], "DODOApproveProxy:Access restricted");
        IDODOApprove(_DODO_APPROVE_).claimTokens(
            token,
            who,
            dest,
            amount
        );
    }

    function isAllowedProxy(address _proxy) external view returns (bool) {
        return _IS_ALLOWED_PROXY_[_proxy];
    }
}

// File: contracts/intf/IERC20.sol

// This is a file copied from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/IERC20.sol

pragma solidity 0.6.9;

/**
 * @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);

    function decimals() external view returns (uint8);

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

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

    /**
     * @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);
}

// File: contracts/lib/SafeMath.sol

/*

    Copyright 2020 DODO ZOO.

*/



/**
 * @title SafeMath
 * @author DODO Breeder
 *
 * @notice Math operations with safety checks that revert on error
 */
library SafeMath {
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "MUL_ERROR");

        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "DIVIDING_ERROR");
        return a / b;
    }

    function divCeil(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 quotient = div(a, b);
        uint256 remainder = a - quotient * b;
        if (remainder > 0) {
            return quotient + 1;
        } else {
            return quotient;
        }
    }

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

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

    function sqrt(uint256 x) internal pure returns (uint256 y) {
        uint256 z = x / 2 + 1;
        y = x;
        while (z < y) {
            y = z;
            z = (x / z + z) / 2;
        }
    }
}

// File: contracts/lib/SafeERC20.sol

/*

    Copyright 2020 DODO ZOO.
    This is a simplified version of OpenZepplin's SafeERC20 library

*/





/**
 * @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 ERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using SafeMath for uint256;

    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)
        );
    }

    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));
    }

    /**
     * @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.

        // A Solidity high level call has three parts:
        //  1. The target address is checked to verify it contains contract code
        //  2. The call itself is made, and success asserted
        //  3. The return value is decoded, which in turn checks the size of the returned data.
        // solhint-disable-next-line max-line-length

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success, "SafeERC20: low-level call failed");

        if (returndata.length > 0) {
            // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// File: contracts/lib/InitializableOwnable.sol

/*

    Copyright 2020 DODO ZOO.

*/


/**
 * @title Ownable
 * @author DODO Breeder
 *
 * @notice Ownership related functions
 */
contract InitializableOwnable {
    address public _OWNER_;
    address public _NEW_OWNER_;
    bool internal _INITIALIZED_;

    // ============ Events ============

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

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

    // ============ Modifiers ============

    modifier notInitialized() {
        require(!_INITIALIZED_, "DODO_INITIALIZED");
        _;
    }

    modifier onlyOwner() {
        require(msg.sender == _OWNER_, "NOT_OWNER");
        _;
    }

    // ============ Functions ============

    function initOwner(address newOwner) public notInitialized {
        _INITIALIZED_ = true;
        _OWNER_ = newOwner;
    }

    function transferOwnership(address newOwner) public onlyOwner {
        emit OwnershipTransferPrepared(_OWNER_, newOwner);
        _NEW_OWNER_ = newOwner;
    }

    function claimOwnership() public {
        require(msg.sender == _NEW_OWNER_, "INVALID_CLAIM");
        emit OwnershipTransferred(_OWNER_, _NEW_OWNER_);
        _OWNER_ = _NEW_OWNER_;
        _NEW_OWNER_ = address(0);
    }
}

// File: contracts/SmartRoute/DODOApprove.sol

/*

    Copyright 2020 DODO ZOO.

*/






/**
 * @title DODOApprove
 * @author DODO Breeder
 *
 * @notice Handle authorizations in DODO platform
 */
contract DODOApprove is InitializableOwnable {
    using SafeERC20 for IERC20;
    
    // ============ Storage ============
    uint256 private constant _TIMELOCK_DURATION_ = 3 days;
    uint256 private constant _TIMELOCK_EMERGENCY_DURATION_ = 24 hours;
    uint256 public _TIMELOCK_;
    address public _PENDING_DODO_PROXY_;
    address public _DODO_PROXY_;

    // ============ Events ============

    event SetDODOProxy(address indexed oldProxy, address indexed newProxy);

    
    // ============ Modifiers ============
    modifier notLocked() {
        require(
            _TIMELOCK_ <= block.timestamp,
            "SetProxy is timelocked"
        );
        _;
    }

    function init(address owner, address initProxyAddress) external {
        initOwner(owner);
        _DODO_PROXY_ = initProxyAddress;
    }

    function unlockSetProxy(address newDodoProxy) public onlyOwner {
        if(_DODO_PROXY_ == address(0))
            _TIMELOCK_ = block.timestamp + _TIMELOCK_EMERGENCY_DURATION_;
        else
            _TIMELOCK_ = block.timestamp + _TIMELOCK_DURATION_;
        _PENDING_DODO_PROXY_ = newDodoProxy;
    }


    function lockSetProxy() public onlyOwner {
       _PENDING_DODO_PROXY_ = address(0);
       _TIMELOCK_ = 0;
    }


    function setDODOProxy() external onlyOwner notLocked() {
        emit SetDODOProxy(_DODO_PROXY_, _PENDING_DODO_PROXY_);
        _DODO_PROXY_ = _PENDING_DODO_PROXY_;
        lockSetProxy();
    }


    function claimTokens(
        address token,
        address who,
        address dest,
        uint256 amount
    ) external {
        require(msg.sender == _DODO_PROXY_, "DODOApprove:Access restricted");
        if (amount > 0) {
            IERC20(token).safeTransferFrom(who, dest, amount);
        }
    }

    function getDODOProxy() public view returns (address) {
        return _DODO_PROXY_;
    }
}