/*

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https://t.me/bubududuerc
https://twitter.com/BUBU_erc
https://twitter.com/DUDU_erc
https://www.bubududu.xyz/

*/
// SPDX-License-Identifier: Unlicensed
// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol

pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol

pragma solidity >=0.6.2;


interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// File: @chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol


pragma solidity ^0.8.0;

interface AggregatorV3Interface {
  function decimals() external view returns (uint8);

  function description() external view returns (string memory);

  function version() external view returns (uint256);

  function getRoundData(uint80 _roundId)
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );

  function latestRoundData()
    external
    view
    returns (
      uint80 roundId,
      int256 answer,
      uint256 startedAt,
      uint256 updatedAt,
      uint80 answeredInRound
    );
}

// File: @openzeppelin/contracts/utils/Context.sol


// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol


// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)

pragma solidity ^0.8.0;


/**
 * @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. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling 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: @openzeppelin/contracts/utils/math/SafeMath.sol


// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol


// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @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: contracts/prod/Base.sol


pragma solidity ^0.8.0;






abstract contract BaseContract is Ownable {

  using SafeMath for uint256;

  struct BubuAccounting{
    uint256 affiliates;
    uint256 team;
    uint256 staking;
  }

  struct DuduAccounting{
    uint256 affiliates;
    uint256 team;
    uint256 staking;
    uint256 burn;
  }

  struct EthAccounting{
    uint256 affiliates;
    uint256 team;
    uint256 staking;
  }

  // ACCOUNTING
  BubuAccounting public bubuAccounting;

  DuduAccounting public duduAccounting;

  EthAccounting public ethAccounting;

  // CHAINLINK CONSTANTS
  address public constant CHAINLINK_AGGREGATOR_USD_ETH = 0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419;
  address public constant CHAINLINK_AGGREGATOR_LINK_ETH = 0xDC530D9457755926550b59e8ECcdaE7624181557;

  // SWAP CONSTANTS
  address public constant UNISWAPV2_ROUTER_ADDRESS = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;
  address public constant WETH_ADDRESS = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
  address public constant USDT_ADDRESS = 0xdAC17F958D2ee523a2206206994597C13D831ec7;
  address public constant DEAD_ADDRESS = 0x000000000000000000000000000000000000dEaD;

  uint256 public ENTRY_PRICE_USDT = 88.88 * 10**6; // 88.88 usdt
  uint256 public ETH_ENTRY_PRICE_INCREASE_PERCENTAGE = 20; // 20%
  uint256 public UINT32_MAX = 2**32-1;

  // CONSTRUCTOR ARGS
  AggregatorV3Interface public immutable linkToEthDataFeed;
  AggregatorV3Interface public immutable usdToEthDataFeed;
  IUniswapV2Router02 public immutable uniswapV2Router;
  IERC20 public immutable bubuToken;
  IERC20 public immutable duduToken;
  address payable public teamFeeReceiver;
  address payable public stakingFeeReceiver;

  // ACCOUNTING + SETTINGS
  uint16 public maxEntriesPerTx = 100; // owner can update
  uint256 public tip = 0.0025 ether;                      // owner can update
  bool public lockBurnEntries = true;                            // owner can update
  bool public lockInitiateDrawing;                        // owner can update
  bool public includeFreeEntriesWithMaxEntries = false;   // owner can update
  bool internal includeFreeEntries = false;
  uint32 public drawingIndex;           // internal
  uint16 public numPayoutAttempts = 5;  // owner can update

  // STATE
  mapping(address => bool) private approvedOwners;
  mapping(address => bool) public isBlacklistedFromPrizes;
  mapping(address => uint256) public amountBurned;

  // EVENTS
  event OwnerApproved(address indexed approvedOwner);
  event OwnerRevoked(address indexed revokedOwner);
  event DrawingInitiated();
  event NoEntries();
  event BurnedEntries(address sender, uint256 numEntries);
  event Received(uint256 amount);

  constructor(
    address _bubuToken,
    address _duduToken,
    address _teamFeeReceiver,
    address _stakingFeeReceiver
  ) {

    linkToEthDataFeed = AggregatorV3Interface(CHAINLINK_AGGREGATOR_LINK_ETH);
    usdToEthDataFeed = AggregatorV3Interface(CHAINLINK_AGGREGATOR_USD_ETH);
    uniswapV2Router = IUniswapV2Router02(UNISWAPV2_ROUTER_ADDRESS);

    bubuToken = IERC20(_bubuToken);
    duduToken = IERC20(_duduToken);

    teamFeeReceiver = payable(_teamFeeReceiver);
    stakingFeeReceiver = payable(_stakingFeeReceiver);
  }

  receive() external payable {
    emit Received(msg.value);
  }

  modifier refundGas {
    uint256 initialGas = gasleft();
    _;
    uint256 gasConsumed = initialGas - gasleft() + 30000;
    (bool success,) = msg.sender.call{value: gasConsumed * block.basefee + tip}("");
    require(success, "refund");
  }

  // ACCESS CONTROL--------------------------------------------------------------
  modifier onlyApprovedOwner() {
      require(msg.sender == owner() || isApprovedOwner(msg.sender), "Not an approved owner");
      _;
  }

  function approveOwner(address _approvedOwner) external onlyApprovedOwner {
    approvedOwners[_approvedOwner] = true;
    emit OwnerApproved(_approvedOwner);
  }

  function revokeOwner(address _revokedOwner) external onlyApprovedOwner {
    approvedOwners[_revokedOwner] = false;
    emit OwnerRevoked(_revokedOwner);
  }

  function isApprovedOwner(address _address) public view returns(bool) {
    return approvedOwners[_address];
  }

  // OWNER ONLY --------------------------------------------------------------
  function setTip(uint256 _tip) public onlyApprovedOwner {
    tip = _tip;
  }

  function setLockInitiateDrawing(bool _lockInitiateDrawing) public onlyApprovedOwner {
    lockInitiateDrawing = _lockInitiateDrawing;
  }

  function setIncludeFreeEntriesWithMaxEntries(bool _includeFreeEntriesWithMaxEntries) public onlyApprovedOwner {
    includeFreeEntriesWithMaxEntries = _includeFreeEntriesWithMaxEntries;
  }

  function setLockBurnEntries(bool _lockBurnEntries) public onlyApprovedOwner {
    lockBurnEntries = _lockBurnEntries;
  }

  function setmaxEntriesPerTx(uint16 _maxEntriesPerTx) public onlyApprovedOwner {
    maxEntriesPerTx = _maxEntriesPerTx;
  }

  function setNumPayoutAttempts(uint16 _numPayoutAttempts) public onlyApprovedOwner {
    require(_numPayoutAttempts > 0, 'must be a value higher than 0');
    numPayoutAttempts = _numPayoutAttempts;
  }

  function setBlacklistedFromPrizes(address _user, bool isBlacklisted) public onlyApprovedOwner {
    // only to be used if someone tries to exploit our on-chain token price lookup.
    isBlacklistedFromPrizes[_user] = isBlacklisted;
  }

  function setTeamFeeReciever(address payable _teamFeeReceiver) public onlyApprovedOwner {
    teamFeeReceiver = _teamFeeReceiver;
  }

  function setStakingFeeReceiver(address payable _stakingFeeReceiver) public onlyApprovedOwner {
    stakingFeeReceiver = _stakingFeeReceiver;
  }

  function setEntryPriceUSDT(uint256 _entryPriceUSDT) public onlyApprovedOwner {
    require(_entryPriceUSDT > 0, 'must be a value higher than 0');
    ENTRY_PRICE_USDT = _entryPriceUSDT * 10**6;
  }

  function setEthEntryPriceIncreasePercentage(uint256 _ethEntryPriceIncreasePercentage) public onlyApprovedOwner {
    require(_ethEntryPriceIncreasePercentage > 0, 'must be a value higher than 0');
    ETH_ENTRY_PRICE_INCREASE_PERCENTAGE = _ethEntryPriceIncreasePercentage;
  }

  // RESCUE ------------------------------------------------------------------
  /**
   * @dev rescues eth from contract
   */
  function rescueEth() public onlyApprovedOwner {
    (bool success,) = owner().call{value: address(this).balance}("");
    require(success);
  }

  /**
   * @dev rescues erc20 tokens sent directly to vault
   */
  function rescueERC20(address token, uint256 amount) public onlyApprovedOwner {
    IERC20(token).transfer(owner(), amount);
  }

  function ethRequiredForUSD(uint256 _numEntries) public view returns (uint256) {
    (,int price,,,) = usdToEthDataFeed.latestRoundData();
    require(price > 0, "Invalid ETH price");
    uint256 ENTRY_ETH_PRICE_USDT = ENTRY_PRICE_USDT * (100 + ETH_ENTRY_PRICE_INCREASE_PERCENTAGE);
    uint256 usdAmount = ENTRY_ETH_PRICE_USDT * _numEntries;
    return (usdAmount * 1e18)/uint256(price);
  }

  /**
   * @dev calculates how many tokens are needed for _numEntries
   */
  function getEntryPrice(uint256 _numEntries, address tokenAddress) public view returns (uint256) {
    address[] memory tokenWethUsdtPath = new address[](3);
    tokenWethUsdtPath[0] = tokenAddress;
    tokenWethUsdtPath[1] = WETH_ADDRESS;
    tokenWethUsdtPath[2] = USDT_ADDRESS;

    return uniswapV2Router.getAmountsIn(ENTRY_PRICE_USDT * _numEntries, tokenWethUsdtPath)[0];
  }

  function burnEntriesCheck(uint16 _numEntries) internal view returns (uint256){
    address sender = msg.sender;

    entryCondition();

    require(tx.origin == sender, "no contracts"); // prevent bots
    require(!lockBurnEntries, "no burn");
    require(!lockInitiateDrawing, "in progress");
    require(!isBlacklistedFromPrizes[sender], "shoo");

    uint256 _allEntries;

    if(includeFreeEntries){
      uint256 _freeEntries = _numEntries / 5;
      _allEntries = _numEntries + _freeEntries;
    } else {
      _allEntries = _numEntries;
    }

    if(!includeFreeEntriesWithMaxEntries)
      require(_numEntries <= maxEntriesPerTx, "tx limit");
    else
      require(_allEntries <= maxEntriesPerTx, "tx limit");
    return _allEntries;
  }

  function afterBurnAddEntries(uint256 amountInMin, uint256 _allEntries) internal {
    address sender = msg.sender;
    amountBurned[sender] += amountInMin;
    uint i;
    for (;i < _allEntries;) {
        addEntry(sender);
        unchecked {++i;}
    }
    emit BurnedEntries(sender, _allEntries);
  }

  function entryCondition() internal view virtual {}

  function addEntry(address sender) internal virtual {}

  function getRandomEntryIndex(uint256 randomness, uint32 i, uint256 total) internal pure returns (uint256) {
    require(total > 0, "No entries available");

    uint256 simulatedRandomness = uint256(keccak256(abi.encode(randomness, i)));
    uint256 index = simulatedRandomness % total;

    return index;
  }


  /**
   * @dev returns max tokens _user can burn at once
   */
  function getMaxBurnableEntries(address _user, address burnTokenAddress) public view returns (uint16) {
    if (isBlacklistedFromPrizes[_user]) {
      return 0;
    }
    address[] memory tokenWethUsdtPath = new address[](3);
    IERC20 burnToken = IERC20(burnTokenAddress);
    tokenWethUsdtPath[0] = burnTokenAddress;
    tokenWethUsdtPath[1] = WETH_ADDRESS;
    tokenWethUsdtPath[2] = USDT_ADDRESS;
    uint256 tokenHoldings = burnToken.balanceOf(_user);
    uint256 usdtOut = uniswapV2Router.getAmountsOut(tokenHoldings, tokenWethUsdtPath)[2];
    uint16 numEntries = uint16(usdtOut / ENTRY_PRICE_USDT);
    if (numEntries > maxEntriesPerTx) {
        numEntries = maxEntriesPerTx;
    }
    return numEntries;
  }

  function enterWithBUBU(uint16 _numEntries, address _affiliates) public {
    address sender = msg.sender;
    uint256 _allEntries = burnEntriesCheck(_numEntries);

    // transfer entry amount
    uint256 amountInMin = getEntryPrice(_numEntries, address(bubuToken));

    if (_affiliates != address(0) && _affiliates != sender) {
      bubuAccounting.affiliates > 0 && bubuToken.transferFrom(sender, _affiliates, amountInMin * bubuAccounting.affiliates/100);
      bubuAccounting.staking > 0 && bubuToken.transferFrom(sender, stakingFeeReceiver, amountInMin * bubuAccounting.staking/100);
      bubuAccounting.team > 0 && bubuToken.transferFrom(sender, teamFeeReceiver, amountInMin * bubuAccounting.team/100);
    } else {
      (bubuAccounting.affiliates > 0 || bubuAccounting.team > 0) && bubuToken.transferFrom(sender, teamFeeReceiver, amountInMin * (bubuAccounting.affiliates + bubuAccounting.team)/100);
      bubuAccounting.staking > 0 && bubuToken.transferFrom(sender, stakingFeeReceiver, amountInMin * bubuAccounting.staking/100);
    }

    uint256 remainder = 100 - (bubuAccounting.affiliates + bubuAccounting.staking + bubuAccounting.team);

    if(remainder > 0){
      bubuToken.transferFrom(sender, address(this), amountInMin * remainder/100);
    }

    afterBurnAddEntries(amountInMin, _allEntries);
  }

  function enterWithDUDU(uint16 _numEntries, address _affiliates) public {
    address sender = msg.sender;
    uint256 _allEntries = burnEntriesCheck(_numEntries);

    // transfer entry amount
    uint256 amountInMin = getEntryPrice(_numEntries, address(duduToken));
    duduAccounting.burn > 0 && duduToken.transferFrom(sender, DEAD_ADDRESS, amountInMin * duduAccounting.burn/100);

    if (_affiliates != address(0) && _affiliates != sender) {
      duduAccounting.affiliates > 0 && duduToken.transferFrom(sender, _affiliates, amountInMin * duduAccounting.affiliates/100);
      duduAccounting.staking > 0 && duduToken.transferFrom(sender, stakingFeeReceiver, amountInMin * duduAccounting.staking/100);
      duduAccounting.team > 0 && duduToken.transferFrom(sender, teamFeeReceiver, amountInMin * duduAccounting.team/100);
    } else {
      (duduAccounting.affiliates > 0 || duduAccounting.team > 0) && duduToken.transferFrom(sender, teamFeeReceiver, amountInMin * (duduAccounting.affiliates + duduAccounting.team)/100);
      duduAccounting.staking > 0 && duduToken.transferFrom(sender, stakingFeeReceiver, amountInMin * duduAccounting.staking/100);
    }

     uint256 remainder = 100 - (duduAccounting.affiliates + duduAccounting.staking + duduAccounting.team + duduAccounting.burn);

    if(remainder > 0){
      duduToken.transferFrom(sender, address(this), amountInMin * remainder/100);
    }

    afterBurnAddEntries(amountInMin, _allEntries);
  }

  function enterWithEth(uint16 _numEntries, address payable _affiliates) public payable {
    address sender = msg.sender;
    uint256 _allEntries = burnEntriesCheck(_numEntries);
    uint256 amountInMin = ethRequiredForUSD(_numEntries);

    require(msg.value >= amountInMin, "Incorrect Ether sent!");

    if (_affiliates != address(0) && _affiliates != sender) {
      if(ethAccounting.affiliates > 0) _affiliates.transfer(msg.value * ethAccounting.affiliates/100);
      if(ethAccounting.team > 0) teamFeeReceiver.transfer(msg.value * ethAccounting.team/100);
    } else {
      if(ethAccounting.team > 0 || ethAccounting.affiliates > 0) teamFeeReceiver.transfer(msg.value * (ethAccounting.team + ethAccounting.affiliates)/100);
    }

    if(ethAccounting.staking > 0) stakingFeeReceiver.transfer(msg.value * ethAccounting.staking/100);
    afterBurnAddEntries(msg.value, _allEntries);
  }

    function setBubuAccounting(uint256 affiliates, uint256 team, uint256 staking) public onlyApprovedOwner {
    bubuAccounting = BubuAccounting({
      affiliates: affiliates,
      team: team,
      staking: staking
    });
  }

  function setDuduAccounting(uint256 affiliates, uint256 team, uint256 staking, uint256 burn) public onlyApprovedOwner {
    duduAccounting = DuduAccounting({
      affiliates: affiliates,
      team: team,
      staking: staking,
      burn: burn
    });
  }

  function setEthAccounting(uint256 affiliates, uint256 team, uint256 staking) public onlyApprovedOwner {
    ethAccounting = EthAccounting({
      team: team,
      staking: staking,
      affiliates: affiliates
    });
  }

}

// File: @chainlink/contracts/src/v0.8/VRFRequestIDBase.sol


pragma solidity ^0.8.0;

contract VRFRequestIDBase {
  /**
   * @notice returns the seed which is actually input to the VRF coordinator
   *
   * @dev To prevent repetition of VRF output due to repetition of the
   * @dev user-supplied seed, that seed is combined in a hash with the
   * @dev user-specific nonce, and the address of the consuming contract. The
   * @dev risk of repetition is mostly mitigated by inclusion of a blockhash in
   * @dev the final seed, but the nonce does protect against repetition in
   * @dev requests which are included in a single block.
   *
   * @param _userSeed VRF seed input provided by user
   * @param _requester Address of the requesting contract
   * @param _nonce User-specific nonce at the time of the request
   */
  function makeVRFInputSeed(
    bytes32 _keyHash,
    uint256 _userSeed,
    address _requester,
    uint256 _nonce
  ) internal pure returns (uint256) {
    return uint256(keccak256(abi.encode(_keyHash, _userSeed, _requester, _nonce)));
  }

  /**
   * @notice Returns the id for this request
   * @param _keyHash The serviceAgreement ID to be used for this request
   * @param _vRFInputSeed The seed to be passed directly to the VRF
   * @return The id for this request
   *
   * @dev Note that _vRFInputSeed is not the seed passed by the consuming
   * @dev contract, but the one generated by makeVRFInputSeed
   */
  function makeRequestId(bytes32 _keyHash, uint256 _vRFInputSeed) internal pure returns (bytes32) {
    return keccak256(abi.encodePacked(_keyHash, _vRFInputSeed));
  }
}

// File: @chainlink/contracts/src/v0.8/interfaces/LinkTokenInterface.sol


pragma solidity ^0.8.0;

interface LinkTokenInterface {
  function allowance(address owner, address spender) external view returns (uint256 remaining);

  function approve(address spender, uint256 value) external returns (bool success);

  function balanceOf(address owner) external view returns (uint256 balance);

  function decimals() external view returns (uint8 decimalPlaces);

  function decreaseApproval(address spender, uint256 addedValue) external returns (bool success);

  function increaseApproval(address spender, uint256 subtractedValue) external;

  function name() external view returns (string memory tokenName);

  function symbol() external view returns (string memory tokenSymbol);

  function totalSupply() external view returns (uint256 totalTokensIssued);

  function transfer(address to, uint256 value) external returns (bool success);

  function transferAndCall(
    address to,
    uint256 value,
    bytes calldata data
  ) external returns (bool success);

  function transferFrom(
    address from,
    address to,
    uint256 value
  ) external returns (bool success);
}

// File: @chainlink/contracts/src/v0.8/VRFConsumerBase.sol


pragma solidity ^0.8.0;



/** ****************************************************************************
 * @notice Interface for contracts using VRF randomness
 * *****************************************************************************
 * @dev PURPOSE
 *
 * @dev Reggie the Random Oracle (not his real job) wants to provide randomness
 * @dev to Vera the verifier in such a way that Vera can be sure he's not
 * @dev making his output up to suit himself. Reggie provides Vera a public key
 * @dev to which he knows the secret key. Each time Vera provides a seed to
 * @dev Reggie, he gives back a value which is computed completely
 * @dev deterministically from the seed and the secret key.
 *
 * @dev Reggie provides a proof by which Vera can verify that the output was
 * @dev correctly computed once Reggie tells it to her, but without that proof,
 * @dev the output is indistinguishable to her from a uniform random sample
 * @dev from the output space.
 *
 * @dev The purpose of this contract is to make it easy for unrelated contracts
 * @dev to talk to Vera the verifier about the work Reggie is doing, to provide
 * @dev simple access to a verifiable source of randomness.
 * *****************************************************************************
 * @dev USAGE
 *
 * @dev Calling contracts must inherit from VRFConsumerBase, and can
 * @dev initialize VRFConsumerBase's attributes in their constructor as
 * @dev shown:
 *
 * @dev   contract VRFConsumer {
 * @dev     constructor(<other arguments>, address _vrfCoordinator, address _link)
 * @dev       VRFConsumerBase(_vrfCoordinator, _link) public {
 * @dev         <initialization with other arguments goes here>
 * @dev       }
 * @dev   }
 *
 * @dev The oracle will have given you an ID for the VRF keypair they have
 * @dev committed to (let's call it keyHash), and have told you the minimum LINK
 * @dev price for VRF service. Make sure your contract has sufficient LINK, and
 * @dev call requestRandomness(keyHash, fee, seed), where seed is the input you
 * @dev want to generate randomness from.
 *
 * @dev Once the VRFCoordinator has received and validated the oracle's response
 * @dev to your request, it will call your contract's fulfillRandomness method.
 *
 * @dev The randomness argument to fulfillRandomness is the actual random value
 * @dev generated from your seed.
 *
 * @dev The requestId argument is generated from the keyHash and the seed by
 * @dev makeRequestId(keyHash, seed). If your contract could have concurrent
 * @dev requests open, you can use the requestId to track which seed is
 * @dev associated with which randomness. See VRFRequestIDBase.sol for more
 * @dev details. (See "SECURITY CONSIDERATIONS" for principles to keep in mind,
 * @dev if your contract could have multiple requests in flight simultaneously.)
 *
 * @dev Colliding `requestId`s are cryptographically impossible as long as seeds
 * @dev differ. (Which is critical to making unpredictable randomness! See the
 * @dev next section.)
 *
 * *****************************************************************************
 * @dev SECURITY CONSIDERATIONS
 *
 * @dev A method with the ability to call your fulfillRandomness method directly
 * @dev could spoof a VRF response with any random value, so it's critical that
 * @dev it cannot be directly called by anything other than this base contract
 * @dev (specifically, by the VRFConsumerBase.rawFulfillRandomness method).
 *
 * @dev For your users to trust that your contract's random behavior is free
 * @dev from malicious interference, it's best if you can write it so that all
 * @dev behaviors implied by a VRF response are executed *during* your
 * @dev fulfillRandomness method. If your contract must store the response (or
 * @dev anything derived from it) and use it later, you must ensure that any
 * @dev user-significant behavior which depends on that stored value cannot be
 * @dev manipulated by a subsequent VRF request.
 *
 * @dev Similarly, both miners and the VRF oracle itself have some influence
 * @dev over the order in which VRF responses appear on the blockchain, so if
 * @dev your contract could have multiple VRF requests in flight simultaneously,
 * @dev you must ensure that the order in which the VRF responses arrive cannot
 * @dev be used to manipulate your contract's user-significant behavior.
 *
 * @dev Since the ultimate input to the VRF is mixed with the block hash of the
 * @dev block in which the request is made, user-provided seeds have no impact
 * @dev on its economic security properties. They are only included for API
 * @dev compatability with previous versions of this contract.
 *
 * @dev Since the block hash of the block which contains the requestRandomness
 * @dev call is mixed into the input to the VRF *last*, a sufficiently powerful
 * @dev miner could, in principle, fork the blockchain to evict the block
 * @dev containing the request, forcing the request to be included in a
 * @dev different block with a different hash, and therefore a different input
 * @dev to the VRF. However, such an attack would incur a substantial economic
 * @dev cost. This cost scales with the number of blocks the VRF oracle waits
 * @dev until it calls responds to a request.
 */
abstract contract VRFConsumerBase is VRFRequestIDBase {
  /**
   * @notice fulfillRandomness handles the VRF response. Your contract must
   * @notice implement it. See "SECURITY CONSIDERATIONS" above for important
   * @notice principles to keep in mind when implementing your fulfillRandomness
   * @notice method.
   *
   * @dev VRFConsumerBase expects its subcontracts to have a method with this
   * @dev signature, and will call it once it has verified the proof
   * @dev associated with the randomness. (It is triggered via a call to
   * @dev rawFulfillRandomness, below.)
   *
   * @param requestId The Id initially returned by requestRandomness
   * @param randomness the VRF output
   */
  function fulfillRandomness(bytes32 requestId, uint256 randomness) internal virtual;

  /**
   * @dev In order to keep backwards compatibility we have kept the user
   * seed field around. We remove the use of it because given that the blockhash
   * enters later, it overrides whatever randomness the used seed provides.
   * Given that it adds no security, and can easily lead to misunderstandings,
   * we have removed it from usage and can now provide a simpler API.
   */
  uint256 private constant USER_SEED_PLACEHOLDER = 0;

  /**
   * @notice requestRandomness initiates a request for VRF output given _seed
   *
   * @dev The fulfillRandomness method receives the output, once it's provided
   * @dev by the Oracle, and verified by the vrfCoordinator.
   *
   * @dev The _keyHash must already be registered with the VRFCoordinator, and
   * @dev the _fee must exceed the fee specified during registration of the
   * @dev _keyHash.
   *
   * @dev The _seed parameter is vestigial, and is kept only for API
   * @dev compatibility with older versions. It can't *hurt* to mix in some of
   * @dev your own randomness, here, but it's not necessary because the VRF
   * @dev oracle will mix the hash of the block containing your request into the
   * @dev VRF seed it ultimately uses.
   *
   * @param _keyHash ID of public key against which randomness is generated
   * @param _fee The amount of LINK to send with the request
   *
   * @return requestId unique ID for this request
   *
   * @dev The returned requestId can be used to distinguish responses to
   * @dev concurrent requests. It is passed as the first argument to
   * @dev fulfillRandomness.
   */
  function requestRandomness(bytes32 _keyHash, uint256 _fee) internal returns (bytes32 requestId) {
    LINK.transferAndCall(vrfCoordinator, _fee, abi.encode(_keyHash, USER_SEED_PLACEHOLDER));
    // This is the seed passed to VRFCoordinator. The oracle will mix this with
    // the hash of the block containing this request to obtain the seed/input
    // which is finally passed to the VRF cryptographic machinery.
    uint256 vRFSeed = makeVRFInputSeed(_keyHash, USER_SEED_PLACEHOLDER, address(this), nonces[_keyHash]);
    // nonces[_keyHash] must stay in sync with
    // VRFCoordinator.nonces[_keyHash][this], which was incremented by the above
    // successful LINK.transferAndCall (in VRFCoordinator.randomnessRequest).
    // This provides protection against the user repeating their input seed,
    // which would result in a predictable/duplicate output, if multiple such
    // requests appeared in the same block.
    nonces[_keyHash] = nonces[_keyHash] + 1;
    return makeRequestId(_keyHash, vRFSeed);
  }

  LinkTokenInterface internal immutable LINK;
  address private immutable vrfCoordinator;

  // Nonces for each VRF key from which randomness has been requested.
  //
  // Must stay in sync with VRFCoordinator[_keyHash][this]
  mapping(bytes32 => uint256) /* keyHash */ /* nonce */
    private nonces;

  /**
   * @param _vrfCoordinator address of VRFCoordinator contract
   * @param _link address of LINK token contract
   *
   * @dev https://docs.chain.link/docs/link-token-contracts
   */
  constructor(address _vrfCoordinator, address _link) {
    vrfCoordinator = _vrfCoordinator;
    LINK = LinkTokenInterface(_link);
  }

  // rawFulfillRandomness is called by VRFCoordinator when it receives a valid VRF
  // proof. rawFulfillRandomness then calls fulfillRandomness, after validating
  // the origin of the call
  function rawFulfillRandomness(bytes32 requestId, uint256 randomness) external {
    require(msg.sender == vrfCoordinator, "Only VRFCoordinator can fulfill");
    fulfillRandomness(requestId, randomness);
  }
}

// File: contracts/prod/Lottery.sol

/*

88                        88                           ,adba,              88                        88
88                        88                           8I  I8              88                        88
88                        88                           "8bdP'              88                        88
88,dPPYba,   88       88  88,dPPYba,   88       88    ,d8"8b  88   ,adPPYb,88  88       88   ,adPPYb,88  88       88
88P'    "8a  88       88  88P'    "8a  88       88  .dP'   Yb,8I  a8"    `Y88  88       88  a8"    `Y88  88       88
88       d8  88       88  88       d8  88       88  8P      888'  8b       88  88       88  8b       88  88       88
88b,   ,a8"  "8a,   ,a88  88b,   ,a8"  "8a,   ,a88  8b,   ,dP8b   "8a,   ,d88  "8a,   ,a88  "8a,   ,d88  "8a,   ,a88
8Y"Ybbd8"'    `"YbbdP'Y8  8Y"Ybbd8"'    `"YbbdP'Y8  `Y8888P"  Yb   `"8bbdP"Y8   `"YbbdP'Y8   `"8bbdP"Y8   `"YbbdP'Y8

https://t.me/bubududuerc
https://twitter.com/BUBU_erc
https://twitter.com/DUDU_erc
https://www.bubududu.xyz/

*/


pragma solidity ^0.8.0;





contract DuduLottery is BaseContract, VRFConsumerBase {

  using SafeMath for uint256;

  bytes32 public constant CHAINLINK_KEY_HASH = 0xAA77729D3466CA35AE8D28B3BBAC7CC36A5031EFDC430821C02BC31A238AF445;
  address public constant CHAINLINK_VRF_COORDINATOR_ADDRESS = 0xf0d54349aDdcf704F77AE15b96510dEA15cb7952;
  address public constant CHAINLINK_ADDRESS = 0x514910771AF9Ca656af840dff83E8264EcF986CA;
  uint256 public constant CHAINLINK_VRF_LINK_FEE = 2.0 * 10**18;

  //STRUCT
  struct Entry {
    address user;
    uint256 purchaseTimestamp;
  }

  IERC20 public immutable linkToken;

  // LOTTERY SETTINGS
  uint256 public secondsBetweenPayouts;       // owner can update, constructor
  uint256 public nextPayoutTime;              // internal, constructor
  uint256 public entryActivePeriod = 604800;  // owner can update, constructor
  uint256 public nextResetTime;               // internal, constructor
  uint256 public totalPaidOut;                // internal
  uint256 public prizePerDrawingInWei;          // owner can update
  uint16 public maxNumWinners = 1;            // owner can update

  // ALL DRAWINGS
  mapping(address => bool) private approvedOwners;
  mapping(address => uint256) public amountWon;
  mapping(uint256 => address[]) public winners;
  mapping(uint256 => Entry) entryLookup;
  mapping(address => uint256) private entriesByUser;

  uint256[] entryKeys;
  uint256 nextEntryIndex = 0;

  event InvalidEntry(uint256 index);
  event RemoveEntry(address addr, uint256 index);
  event Winner(address winner, uint256 prize);
  event Loser(address loser, uint256 wouldBePrize);

  constructor(
    address _bubuToken,
    address _duduToken,
    address _teamFeeReceiver,
    address _stakingFeeReceiver,
    uint256 _secondsBetweenPayouts,
    uint256 _prizePerDrawingInWei
  ) BaseContract(_bubuToken, _duduToken, _teamFeeReceiver, _stakingFeeReceiver)
    VRFConsumerBase(CHAINLINK_VRF_COORDINATOR_ADDRESS, CHAINLINK_ADDRESS) {

    // Entry price for supported tokens and eth (also has setter functions)
    ENTRY_PRICE_USDT = 88 * 10**6; // 88 usdt;
    ETH_ENTRY_PRICE_INCREASE_PERCENTAGE = 20; // 20%

    linkToken = IERC20(CHAINLINK_ADDRESS);

    includeFreeEntries = true;

    prizePerDrawingInWei = _prizePerDrawingInWei;
    secondsBetweenPayouts = _secondsBetweenPayouts;

    nextPayoutTime = block.timestamp + secondsBetweenPayouts;

    bubuAccounting = BubuAccounting({
      affiliates: 15,
      team: 85,
      staking: 0
    });

    duduAccounting = DuduAccounting({
      affiliates: 10,
      team: 25,
      staking: 25,
      burn: 40
    });

    ethAccounting = EthAccounting({
      team: 50,
      staking: 35,
      affiliates: 15
    });
  }

  // DRAWING CORE MECHANICS --------------------------------------------------
  function initiateDrawing() public refundGas {
      // reverts if drawing already initiated or if its not time for next drawing
      require(!lockInitiateDrawing, "in progress");
      require(tx.origin == msg.sender, "no contract calls");
      require(block.timestamp >= nextPayoutTime, "too soon");

      //invalidate past entries to get actual length of existing entries
      invalidatePastEntries();

      if(entryKeys.length == 0){
        emit NoEntries();
        drawingIndex++;
        nextPayoutTime = block.timestamp + secondsBetweenPayouts;
      }
      else {
        getLinkAndStartDraw();
      }
  }

  function fulfillRandomness(bytes32 /*requestId*/, uint256 randomness) internal override {
    // Distribute prize via chainlink VRF response, can only be called by chainlink VRF
    require(lockInitiateDrawing, "not in progress");
    lockInitiateDrawing = false;

    uint256 timestamp = block.timestamp;
    address _addr;
    uint32 numWinners;
    uint32 i;
    bool foundWinner;
    uint256 randomIndex;

    // Select random addresses from the VRF response until we find N winners
    for (;i<numPayoutAttempts;) {
      if (numWinners >= maxNumWinners) break;

      // Select new random address on each loop
      randomIndex = getRandomEntryIndex(randomness, i, entryKeys.length);
      _addr = entryLookup[entryKeys[randomIndex]].user;

      // Skip if blacklisted
      if (isBlacklistedFromPrizes[_addr]) {
        emit Loser(_addr, prizePerDrawingInWei);
        unchecked {++i;}
        continue;
      }

      foundWinner = true;

      // Send eth, reentrancy not possible due to internal function
      (bool success,) = _addr.call{value: prizePerDrawingInWei}("");
      require(success, "!call");

      removeEntry(entryKeys[randomIndex]);

      // Update accounting
      unchecked {
        ++numWinners;
        totalPaidOut += prizePerDrawingInWei;
        nextPayoutTime = timestamp + secondsBetweenPayouts;
        amountWon[_addr] += prizePerDrawingInWei;
        winners[drawingIndex].push(_addr);
        drawingIndex++;
      }

      // Emit
      emit Winner(_addr, prizePerDrawingInWei);
      unchecked {++i;}
    }
  }

  // OWNER ONLY --------------------------------------------------------------

  function setMaxNumWinners(uint16 _maxNumWinners) public onlyApprovedOwner {
    require(_maxNumWinners > 0);
    maxNumWinners = _maxNumWinners;
  }

  function setMaxPrizePerDrawing(uint256 _prizePerDrawingInWei) public onlyApprovedOwner {
    require(_prizePerDrawingInWei > 0);
    prizePerDrawingInWei = _prizePerDrawingInWei;
  }

  function setSecondsBetweenPayouts(uint256 _secondsBetweenPayouts) public onlyApprovedOwner {
    require(_secondsBetweenPayouts > 0);
    secondsBetweenPayouts = _secondsBetweenPayouts;
  }

  function setEntryActivePeriod(uint256 _entryActivePeriod) public onlyApprovedOwner {
    require(_entryActivePeriod > 0);
    entryActivePeriod = _entryActivePeriod;
  }

  // VIEWS -------------------------------------------------------------------

  function entryCondition() internal view override {
    require(address(this).balance > prizePerDrawingInWei, "Contract has low funds");
  }

  function tooSoon() public view returns (bool){
    return block.timestamp >= nextPayoutTime;
  }

  function getWinningAddresses(uint256 drawIndex) public view returns(address[] memory) {
    return winners[drawIndex];
  }

  function getNumberOfEntriesForUser(address _addr) public view returns (uint256) {
    uint256 total = 0;
    uint256 currentTimestamp = block.timestamp;

    for (uint256 i = 0; i < entryKeys.length; i++) {
      if (entryLookup[entryKeys[i]].user == _addr &&
          entryLookup[entryKeys[i]].purchaseTimestamp + entryActivePeriod > currentTimestamp
        ) {
        total++;
      }
    }
    return total;
  }

  function getTotalActiveEntries() public view returns (uint256) {
    uint256 total = 0;
    uint256 currentTimestamp = block.timestamp;

    for (uint256 i = 0; i < entryKeys.length; i++) {
      if (entryLookup[entryKeys[i]].purchaseTimestamp + entryActivePeriod > currentTimestamp) {
        total++;
      }
    }
    return total;
  }

  function balanceOfLink() public view returns (uint256){
    return linkToken.balanceOf(address(this));
  }

  function addEntry(address sender) internal override {
      Entry memory newEntry = Entry({ purchaseTimestamp: block.timestamp, user: sender });

      entryLookup[nextEntryIndex] = newEntry;
      entryKeys.push(nextEntryIndex);
      entriesByUser[sender] = entriesByUser[sender].add(1);
      nextEntryIndex++;
  }

  function removeEntry(uint256 entryKey) internal {
    require(entryLookup[entryKey].user != address(0), "This entry does not exist");
    address addr = entryLookup[entryKey].user;

    entriesByUser[addr] = entriesByUser[addr].sub(1);
    for (uint256 i = 0; i < entryKeys.length; i++) {
      if (entryKeys[i] == entryKey) {
        entryKeys[i] = entryKeys[entryKeys.length - 1];
        entryKeys.pop();
        break;
      }
    }

    emit RemoveEntry(addr, entryKey);
    delete entryLookup[entryKey];
  }

  function invalidatePastEntries() internal {
    uint256 i = 0;
    while (i < entryKeys.length) {
      if (entryLookup[entryKeys[i]].purchaseTimestamp + entryActivePeriod <= block.timestamp) {
        entriesByUser[entryLookup[entryKeys[i]].user] = entriesByUser[entryLookup[entryKeys[i]].user].sub(1);
        delete entryLookup[entryKeys[i]];
        entryKeys[i] = entryKeys[entryKeys.length - 1];
        entryKeys.pop();
      } else {
        i++;
      }
    }
  }

  function getLinkAndStartDraw() internal {
    // Re-up chainlink in bulk, as-needed, to save gas on most drawings
    if (linkToken.balanceOf(address(this)) < CHAINLINK_VRF_LINK_FEE) {
        // prevent sandwiches
        (,int256 linkEthPrice,,,) = linkToEthDataFeed.latestRoundData();
        // get swap path
        address[] memory wethLinkPath = new address[](2);
        wethLinkPath[0] = WETH_ADDRESS;
        wethLinkPath[1] = CHAINLINK_ADDRESS;
        // swap ETH into link on uniswap, excess ETH is refunded
        uniswapV2Router.swapETHForExactTokens{value: uint256(linkEthPrice) * 12}(
            10 * 10**18,
            wethLinkPath,
            address(this),
            block.timestamp
        );
    }

    // Trigger chainlink vrf to call fulfillRandomness
    requestRandomness(CHAINLINK_KEY_HASH, CHAINLINK_VRF_LINK_FEE);
    emit DrawingInitiated();
    lockInitiateDrawing = true;
  }

}