// Modified for use with SYNC, modifications not made by Zapper

// Copyright (C) 2020 zapper, nodar, suhail, seb, sumit, apoorv

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 2 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 Affero General Public License for more details.
//

///@author Zapper
///@notice This contract adds liquidity to Uniswap V2 pools using ETH or any ERC20 Token.
// SPDX-License-Identifier: GPLv2

pragma solidity ^0.6.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP. Does not include
 * the optional functions; to access them see {ERC20Detailed}.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

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

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

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

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

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

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

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

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     *
     * _Available since v2.4.0._
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

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

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

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

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     * - The divisor cannot be zero.
     *
     * _Available since v2.4.0._
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
        // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
        // for accounts without code, i.e. `keccak256('')`
        bytes32 codehash;


            bytes32 accountHash
         = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        // solhint-disable-next-line no-inline-assembly
        assembly {
            codehash := extcodehash(account)
        }
        return (codehash != accountHash && codehash != 0x0);
    }

    /**
     * @dev Converts an `address` into `address payable`. Note that this is
     * simply a type cast: the actual underlying value is not changed.
     *
     * _Available since v2.4.0._
     */
    function toPayable(address account)
        internal
        pure
        returns (address payable)
    {
        return address(uint160(account));
    }

    /**
     * @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].
     *
     * _Available since v2.4.0._
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(
            address(this).balance >= amount,
            "Address: insufficient balance"
        );

        // solhint-disable-next-line avoid-call-value
        (bool success, ) = recipient.call.value(amount)("");
        require(
            success,
            "Address: unable to send value, recipient may have reverted"
        );
    }
}

/**
 * @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;
    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)
        );
    }

    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        callOptionalReturn(
            token,
            abi.encodeWithSelector(token.approve.selector, spender, value)
        );
    }

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

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(
            value,
            "SafeERC20: decreased allowance below zero"
        );
        callOptionalReturn(
            token,
            abi.encodeWithSelector(
                token.approve.selector,
                spender,
                newAllowance
            )
        );
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves.

        // 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
        require(address(token).isContract(), "SafeERC20: call to non-contract");

        // 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"
            );
        }
    }
}

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * _Since v2.5.0:_ this module is now much more gas efficient, given net gas
 * metering changes introduced in the Istanbul hardfork.
 */
contract ReentrancyGuard {
    bool private _notEntered;

    constructor() internal {
        // Storing an initial non-zero value makes deployment a bit more
        // expensive, but in exchange the refund on every call to nonReentrant
        // will be lower in amount. Since refunds are capped to a percetange of
        // the total transaction's gas, it is best to keep them low in cases
        // like this one, to increase the likelihood of the full refund coming
        // into effect.
        _notEntered = true;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_notEntered, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _notEntered = false;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _notEntered = true;
    }
}

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
contract Context {
    // Empty internal constructor, to prevent people from mistakenly deploying
    // an instance of this contract, which should be used via inheritance.
    constructor() internal {}

    // solhint-disable-previous-line no-empty-blocks

    function _msgSender() internal view returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

/**
 * @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.
 *
 * 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.
 */
contract Ownable is Context {
    address payable public _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() internal {
        address payable msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

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

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

    /**
     * @dev Returns true if the caller is the current owner.
     */
    function isOwner() public view returns (bool) {
        return _msgSender() == _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 onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address payable newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     */
    function _transferOwnership(address payable newOwner) internal {
        require(
            newOwner != address(0),
            "Ownable: new owner is the zero address"
        );
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

// import "@uniswap/lib/contracts/libraries/Babylonian.sol";
library Babylonian {
    function sqrt(uint256 y) internal pure returns (uint256 z) {
        if (y > 3) {
            z = y;
            uint256 x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
        // else z = 0
    }
}

interface IWETH {
    function deposit() external payable;

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

    function withdraw(uint256) external;
}

interface IUniswapV2Factory {
    function getPair(address tokenA, address tokenB)
        external
        view
        returns (address);
}

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

    function WETH() external pure returns (address);

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

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

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

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

    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountA, uint256 amountB);

    function removeLiquidityETHWithPermit(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountToken, uint256 amountETH);

    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapTokensForExactTokens(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactETHForTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function swapTokensForExactETH(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactTokensForETH(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapETHForExactTokens(
        uint256 amountOut,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountETH);

    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountETH);

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

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

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

    function quote(
        uint256 amountA,
        uint256 reserveA,
        uint256 reserveB
    ) external pure returns (uint256 amountB);

    function getAmountOut(
        uint256 amountIn,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountOut);

    function getAmountIn(
        uint256 amountOut,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountIn);

    function getAmountsOut(uint256 amountIn, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);

    function getAmountsIn(uint256 amountOut, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);
}

interface IUniswapV2Pair {
    function token0() external pure returns (address);

    function token1() external pure returns (address);

    function getReserves()
        external
        view
        returns (
            uint112 _reserve0,
            uint112 _reserve1,
            uint32 _blockTimestampLast
        );
}

contract ZapInModified is ReentrancyGuard, Ownable {
    using SafeMath for uint256;
    using Address for address;
    using SafeERC20 for IERC20;

    bool public stopped = false;

    IUniswapV2Router02 private constant uniswapRouter = IUniswapV2Router02(
        0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
    );

    IUniswapV2Factory
        private constant UniSwapV2FactoryAddress = IUniswapV2Factory(
        0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f
    );

    address
        private wethTokenAddress;

    uint256
        private constant deadline = 0xf000000000000000000000000000000000000000000000000000000000000000;

    constructor() public {
        wethTokenAddress=uniswapRouter.WETH();
    }

    // circuit breaker modifiers
    modifier stopInEmergency {
        if (stopped) {
            revert("Temporarily Paused");
        } else {
            _;
        }
    }

    /**
    @notice This function is used to invest in given Uniswap V2 pair through ETH/ERC20 Tokens
    @param _FromTokenContractAddress The ERC20 token used for investment (address(0x00) if ether)
    @param _ToUnipoolToken0 The Uniswap V2 pair token0 address
    @param _ToUnipoolToken1 The Uniswap V2 pair token1 address
    @param _amount The amount of fromToken to invest
    @param _minPoolTokens Reverts if less tokens received than this
    @return Amount of LP bought
     */
    function ZapIn(
        address _toWhomToIssue,
        address _FromTokenContractAddress,
        address _ToUnipoolToken0,
        address _ToUnipoolToken1,
        uint256 _amount,
        uint256 _minPoolTokens
    ) public payable nonReentrant stopInEmergency returns (uint256) {
        uint256 toInvest;
        if (_FromTokenContractAddress == address(0)) {
            require(msg.value > 0, "Error: ETH not sent");
            toInvest = msg.value;
        } else {
            require(msg.value == 0, "Error: ETH sent");
            require(_amount > 0, "Error: Invalid ERC amount");
            IERC20(_FromTokenContractAddress).safeTransferFrom(
                msg.sender,
                address(this),
                _amount
            );
            toInvest = _amount;
        }

        uint256 LPBought = _performZapIn(
            _toWhomToIssue,
            _FromTokenContractAddress,
            _ToUnipoolToken0,
            _ToUnipoolToken1,
            toInvest
        );
        require(LPBought >= _minPoolTokens, "ERR: High Slippage");

        //get pair address
        address _ToUniPoolAddress = UniSwapV2FactoryAddress.getPair(
            _ToUnipoolToken0,
            _ToUnipoolToken1
        );

        IERC20(_ToUniPoolAddress).safeTransfer(
            _toWhomToIssue,
            LPBought
        );
        return LPBought;
    }
    event DebugZap(uint256 ethToTrade,uint256 tokens0,uint256 tokens1,uint256 liquidityObtained);
    function _performZapIn(
        address _toWhomToIssue,
        address _FromTokenContractAddress,
        address _ToUnipoolToken0,
        address _ToUnipoolToken1,
        uint256 _amount
    ) internal returns (uint256) {
        address intermediate = _getIntermediate(
            _FromTokenContractAddress,
            _amount,
            _ToUnipoolToken0,
            _ToUnipoolToken1
        );

        // swap to intermediate
        uint256 interAmt = _token2Token(
            _FromTokenContractAddress,
            intermediate,
            _amount
        );

        // divide to swap in amounts
        uint256 token0Bought;
        uint256 token1Bought;

        IUniswapV2Pair pair = IUniswapV2Pair(
            UniSwapV2FactoryAddress.getPair(_ToUnipoolToken0, _ToUnipoolToken1)
        );
        (uint256 res0, uint256 res1, ) = pair.getReserves();
        uint256 amountToSwap;
        if (intermediate == _ToUnipoolToken0) {
            amountToSwap = calculateSwapInAmount(res0, interAmt);
            //if no reserve or a new pair is created
            if (amountToSwap <= 0) amountToSwap = interAmt.div(2);
            token1Bought = _token2Token(
                intermediate,
                _ToUnipoolToken1,
                amountToSwap
            );
            token0Bought = interAmt.sub(amountToSwap);
        } else {
            amountToSwap = calculateSwapInAmount(res1, interAmt);
            //if no reserve or a new pair is created
            if (amountToSwap <= 0) amountToSwap = interAmt.div(2);
            token0Bought = _token2Token(
                intermediate,
                _ToUnipoolToken0,
                amountToSwap
            );
            token1Bought = interAmt.sub(amountToSwap);
        }

        uint256 lobt=_uniDeposit(
            _toWhomToIssue,
            _ToUnipoolToken0,
            _ToUnipoolToken1,
            token0Bought,
            token1Bought
        );
        emit DebugZap(amountToSwap,token0Bought,token1Bought,lobt);
        return
            lobt;
    }

    function _uniDeposit(
        address _toWhomToIssue,
        address _ToUnipoolToken0,
        address _ToUnipoolToken1,
        uint256 token0Bought,
        uint256 token1Bought
    ) internal returns (uint256) {
        IERC20(_ToUnipoolToken0).safeApprove(
            address(uniswapRouter),
            token0Bought
        );
        IERC20(_ToUnipoolToken1).safeApprove(
            address(uniswapRouter),
            token1Bought
        );

        (uint256 amountA, uint256 amountB, uint256 LP) = uniswapRouter
            .addLiquidity(
            _ToUnipoolToken0,
            _ToUnipoolToken1,
            token0Bought,
            token1Bought,
            1,
            1,
            address(this),
            deadline
        );

        IERC20(_ToUnipoolToken0).safeApprove(
            address(uniswapRouter),
            0
        );
        IERC20(_ToUnipoolToken1).safeApprove(
            address(uniswapRouter),
            0
        );

        //Returning Residue in token0, if any.
        if (token0Bought.sub(amountA) > 0) {
            IERC20(_ToUnipoolToken0).safeTransfer(
                _toWhomToIssue,
                token0Bought.sub(amountA)
            );
        }

        //Returning Residue in token1, if any
        if (token1Bought.sub(amountB) > 0) {
            IERC20(_ToUnipoolToken1).safeTransfer(
                _toWhomToIssue,
                token1Bought.sub(amountB)
            );
        }

        return LP;
    }

    function _getIntermediate(
        address _FromTokenContractAddress,
        uint256 _amount,
        address _ToUnipoolToken0,
        address _ToUnipoolToken1
    ) internal view returns (address) {
        // set from to weth for eth input
        if (_FromTokenContractAddress == address(0)) {
            _FromTokenContractAddress = wethTokenAddress;
        }

        if (_FromTokenContractAddress == _ToUnipoolToken0) {
            return _ToUnipoolToken0;
        } else if (_FromTokenContractAddress == _ToUnipoolToken1) {
            return _ToUnipoolToken1;
        } else if(_ToUnipoolToken0 == wethTokenAddress || _ToUnipoolToken1 == wethTokenAddress) {
            return wethTokenAddress;
        } else {
            IUniswapV2Pair pair = IUniswapV2Pair(
                UniSwapV2FactoryAddress.getPair(
                    _ToUnipoolToken0,
                    _ToUnipoolToken1
                )
            );
            (uint256 res0, uint256 res1, ) = pair.getReserves();

            uint256 ratio;
            bool isToken0Numerator;
            if (res0 >= res1) {
                ratio = res0 / res1;
                isToken0Numerator = true;
            } else {
                ratio = res1 / res0;
            }

            //find outputs on swap
            uint256 output0 = _calculateSwapOutput(
                _FromTokenContractAddress,
                _amount,
                _ToUnipoolToken0
            );
            uint256 output1 = _calculateSwapOutput(
                _FromTokenContractAddress,
                _amount,
                _ToUnipoolToken1
            );

            if (isToken0Numerator) {
                if (output1 * ratio >= output0) return _ToUnipoolToken1;
                else return _ToUnipoolToken0;
            } else {
                if (output0 * ratio >= output1) return _ToUnipoolToken0;
                else return _ToUnipoolToken1;
            }
        }
    }

    function _calculateSwapOutput(
        address _from,
        uint256 _amt,
        address _to
    ) internal view returns (uint256) {
        // check output via tokenA -> tokenB
        address pairA = UniSwapV2FactoryAddress.getPair(_from, _to);

        uint256 amtA;
        if (pairA != address(0)) {
            address[] memory pathA = new address[](2);
            pathA[0] = _from;
            pathA[1] = _to;

            amtA = uniswapRouter.getAmountsOut(_amt, pathA)[1];
        }

        uint256 amtB;
        // check output via tokenA -> weth -> tokenB
        if ((_from != wethTokenAddress) && _to != wethTokenAddress) {
            address[] memory pathB = new address[](3);
            pathB[0] = _from;
            pathB[1] = wethTokenAddress;
            pathB[2] = _to;

            amtB = uniswapRouter.getAmountsOut(_amt, pathB)[2];
        }

        if (amtA >= amtB) {
            return amtA;
        } else {
            return amtB;
        }
    }

    /*
    */
    function zapInSimple(
      address _lptaddress,
      uint256 _minPoolTokens
    ) public payable{
      IUniswapV2Pair pair = IUniswapV2Pair(_lptaddress);
      ZapIn(
          msg.sender,
          address(0),
          pair.token0(),
          pair.token1(),
          0,
          _minPoolTokens
      );
    }

    /*
      Calculates the value to put in for minpooltokens. Should not be used in the same transaction as zapIn. Slippage as a fraction of 10000 (1% -> 100, 15% -> 1500, etc.).
    */
    function calculateMinPoolTokens(
    address _pair,
    uint256 _amount,
    uint256 _slippage) external view returns(uint256){
      uint256 numTokens=getResultingTokens(_pair,_amount);
      return numTokens.sub(numTokens.mul(_slippage).div(10000));
    }

    function getResultingTokens(
    address _pair,
    uint256 _amount) public view returns(uint256){
      IUniswapV2Pair pair = IUniswapV2Pair(
          _pair//UniSwapV2FactoryAddress.getPair(_ToUnipoolToken0, _ToUnipoolToken1)
      );

      address intermediate = _getIntermediate(
          address(0),
          _amount,
          pair.token0(),
          pair.token1()
      );

      uint256 interAmount=_amount;
      if(intermediate != wethTokenAddress){
        IUniswapV2Pair pairUpstream = IUniswapV2Pair(
            UniSwapV2FactoryAddress.getPair(wethTokenAddress, intermediate)
        );
        (uint256 resu0, uint256 resu1, ) = pairUpstream.getReserves();
        interAmount=uniswapRouter.getAmountOut(
          _amount,
          pairUpstream.token0()==wethTokenAddress ? resu0 : resu1,
          pairUpstream.token0()==wethTokenAddress ? resu1 : resu0
        );
      }

      (uint256 res0, uint256 res1, ) = pair.getReserves();

      if(pair.token0()==intermediate){
        uint256 toSwapAmount=calculateSwapInAmount(res0, interAmount);
        return getTokensAcquired(res0,IERC20(address(pair)).totalSupply(),interAmount.sub(toSwapAmount));
      }
      else{
        uint256 toSwapAmount=calculateSwapInAmount(res1, interAmount);
        return getTokensAcquired(res1,IERC20(address(pair)).totalSupply(),interAmount.sub(toSwapAmount));
      }
    }

    function getTokensAcquired(uint256 reserve,uint256 totalSupply,uint256 amount) public view returns(uint256){
      return totalSupply.mul(amount).div(reserve.add(amount));
    }

    function calculateSwapInAmount(uint256 reserveIn, uint256 userIn)
        public
        pure
        returns (uint256)
    {
        return
            Babylonian
                .sqrt(
                reserveIn.mul(userIn.mul(3988000) + reserveIn.mul(3988009))
            )
                .sub(reserveIn.mul(1997)) / 1994;
    }

    event DebugTokenSwap(address from, address to,uint256 totrade,uint256 bought);
    /**
    @notice This function is used to swap ETH/ERC20 <> ETH/ERC20
    @param _FromTokenContractAddress The token address to swap from. (0x00 for ETH)
    @param _ToTokenContractAddress The token address to swap to. (0x00 for ETH)
    @param tokens2Trade The amount of tokens to swap
    @return tokenBought The quantity of tokens bought
    */
    function _token2Token(
        address _FromTokenContractAddress,
        address _ToTokenContractAddress,
        uint256 tokens2Trade
    ) internal returns (uint256 tokenBought) {
        if (_FromTokenContractAddress == _ToTokenContractAddress) {
            return tokens2Trade;
        }

        if (_FromTokenContractAddress == address(0)) {
            if (_ToTokenContractAddress == wethTokenAddress) {
                IWETH(wethTokenAddress).deposit.value(tokens2Trade)();
                return tokens2Trade;
            }

            address[] memory path = new address[](2);
            path[0] = wethTokenAddress;
            path[1] = _ToTokenContractAddress;
            tokenBought = uniswapRouter.swapExactETHForTokens.value(
                tokens2Trade
            )(1, path, address(this), deadline)[path.length - 1];
        } else if (_ToTokenContractAddress == address(0)) {
            if (_FromTokenContractAddress == wethTokenAddress) {
                IWETH(wethTokenAddress).withdraw(tokens2Trade);
                return tokens2Trade;
            }

            IERC20(_FromTokenContractAddress).safeApprove(
                address(uniswapRouter),
                tokens2Trade
            );

            address[] memory path = new address[](2);
            path[0] = _FromTokenContractAddress;
            path[1] = wethTokenAddress;
            tokenBought = uniswapRouter.swapExactTokensForETH(
                tokens2Trade,
                1,
                path,
                address(this),
                deadline
            )[path.length - 1];
        } else {
            IERC20(_FromTokenContractAddress).safeApprove(
                address(uniswapRouter),
                tokens2Trade
            );

            if (_FromTokenContractAddress != wethTokenAddress) {
                if (_ToTokenContractAddress != wethTokenAddress) {
                    // check output via tokenA -> tokenB
                    address pairA = UniSwapV2FactoryAddress.getPair(
                        _FromTokenContractAddress,
                        _ToTokenContractAddress
                    );
                    address[] memory pathA = new address[](2);
                    pathA[0] = _FromTokenContractAddress;
                    pathA[1] = _ToTokenContractAddress;
                    uint256 amtA;
                    if (pairA != address(0)) {
                        amtA = uniswapRouter.getAmountsOut(
                            tokens2Trade,
                            pathA
                        )[1];
                    }

                    // check output via tokenA -> weth -> tokenB
                    address[] memory pathB = new address[](3);
                    pathB[0] = _FromTokenContractAddress;
                    pathB[1] = wethTokenAddress;
                    pathB[2] = _ToTokenContractAddress;

                    uint256 amtB = uniswapRouter.getAmountsOut(
                        tokens2Trade,
                        pathB
                    )[2];

                    if (amtA >= amtB) {
                        tokenBought = uniswapRouter.swapExactTokensForTokens(
                            tokens2Trade,
                            1,
                            pathA,
                            address(this),
                            deadline
                        )[pathA.length - 1];
                    } else {
                        tokenBought = uniswapRouter.swapExactTokensForTokens(
                            tokens2Trade,
                            1,
                            pathB,
                            address(this),
                            deadline
                        )[pathB.length - 1];
                    }
                } else {
                    address[] memory path = new address[](2);
                    path[0] = _FromTokenContractAddress;
                    path[1] = wethTokenAddress;

                    tokenBought = uniswapRouter.swapExactTokensForTokens(
                        tokens2Trade,
                        1,
                        path,
                        address(this),
                        deadline
                    )[path.length - 1];
                }
            } else {
                address[] memory path = new address[](2);
                path[0] = wethTokenAddress;
                path[1] = _ToTokenContractAddress;
                tokenBought = uniswapRouter.swapExactTokensForTokens(
                    tokens2Trade,
                    1,
                    path,
                    address(this),
                    deadline
                )[path.length - 1];
            }
        }
        require(tokenBought > 0, "Error Swapping Tokens");

        emit DebugTokenSwap(_FromTokenContractAddress, _ToTokenContractAddress,tokens2Trade,tokenBought);
    }

    function inCaseTokengetsStuck(IERC20 _TokenAddress) public onlyOwner {
        uint256 qty = _TokenAddress.balanceOf(address(this));
        _TokenAddress.safeTransfer(owner(), qty);
    }

    // - to Pause the contract
    function toggleContractActive() public onlyOwner {
        stopped = !stopped;
    }

    // - to withdraw any ETH balance sitting in the contract
    function withdraw() public onlyOwner {
        uint256 contractBalance = address(this).balance;
        address payable _to = owner().toPayable();
        _to.transfer(contractBalance);
    }

}

{
  "compilationTarget": {
    "ZapInModified.sol": "ZapInModified"
  },
  "evmVersion": "istanbul",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "remappings": []
}