Lottery

Contract info

Contract name: PancakeSwapLottery
Contract address: 0x5aF6D33DE2ccEC94efb1bDF8f92Bd58085432d2c
Random number generator address: 0x8c6375Aab6e5B26a30bF241EBBf29AD6e6c503c2
(Random number generator contract must be deployed first)

View PancakeSwapLottery.sol on BscScan.

View the PancakeSwap: Lottery contract on BscScan.

Audits

The PancakeSwap Lottery V2 has been audited twice so far. View the results below:

Peckshield's Lottery V2 Audit

Slowmist's Lottery V2 Audit

Lottery Status states

The lottery has four Status states, Pending, Open, Close, and Claimable, that determine which actions can and cannot be taken at a given time.

Read/View functions

viewCurrentLotteryId

function viewCurrentLotteryId() external view override returns (uint256);

Returns the Id# of the current Lottery round as an integer. Round Id#s correlate to round number, and are incremental, e.g. the ninth round of Lottery will be 9.

viewLottery

function viewLottery(uint256 _lotteryId) external view returns (Lottery memory);

Returns information on specified Lottery round as tuple (see Lottery structure below).

        uint256 startTime;
        uint256 endTime;
        uint256 priceTicketInCake;
        uint256 discountDivisor;
        uint256[6] rewardsBreakdown; // 0: 1 matching number // 5: 6 matching numbers
        uint256 treasuryFee; // 500: 5% // 200: 2% // 50: 0.5%
        uint256[6] cakePerBracket;
        uint256[6] countWinnersPerBracket;
        uint256 firstTicketId;
        uint256 firstTicketIdNextLottery;
        uint256 amountCollectedInCake;
        uint32 finalNumber;

viewNumbersAndStatusesForTicketIds

function viewNumbersAndStatusesForTicketIds(uint256[] calldata _ticketIds)
    external
    view
    returns (uint32[] memory, bool[] memory);

Returns the corresponding numbers and the statuses of ticketIds array of tickets defined by their ticketId.

viewRewardsForTicketId

function viewRewardsForTicketId(
    uint256 _lotteryId,
    uint256 _ticketId,
    uint32 _bracket;

Calculates rewards for a ticket after draw given the lotteryId, ticketId, and bracket. Filling and querying will provide a link to detailed price information on BscScan.

viewUserInfoForLotteryId

    function viewUserInfoForLottery(
        address _user,
        uint256 _lotteryId,
        uint256 _cursor,
        uint256 _size
    )
        external
        view
        returns (
            uint256[] memory,
            uint32[] memory,
            bool[] memory,
            uint256
        )

Returns user lotteryTicketIds, ticketNumbers, and ticketStatuses of a user for a given Lottery (defined by lotteryID).

calculateRewardsForTicketId

    function _calculateRewardsForTicketId(
        uint256 _lotteryId,
        uint256 _ticketId,
        uint32 _bracket
    ) internal view returns (uint256);

Calculates rewards for a ticket after draw given the lotteryId, ticketId, and bracket.

calculateTotalPriceForBulkTickets

    function calculateTotalPriceForBulkTickets(
        uint256 _discountDivisor,
        uint256 _priceTicket,
        uint256 _numberTickets
    ) external pure returns (uint256);

Calculates the price for a set of tickets accounting for bulk discount.

discountDivisor:

$totalPriceForBulkTickets = priceSingleTicket \cdot numberTickets \cdot \frac{(discountDivisor + 1 - numberTickets)}{discountDivisor}$

Filling and querying will provide a link to detailed price information on BscScan.

Write functions (users)

buyTickets

function buyTickets(uint256 _lotteryId, uint32[] calldata _ticketNumbers) external override notContract nonReentrant;

Buy tickets for the current Open Lottery round (between 1 and 100 per purchase). Calculates the price per ticket using calculateTotalPriceForBulkTickets.

claimTickets

    function claimTickets(
        uint256 _lotteryId,
        uint256[] calldata _ticketIds,
        uint32[] calldata _brackets
    ) external override notContract nonReentrant;

Claim a set of winning tickets for a Claimable Lottery round. Checks lotteryId to determine if round is claimable, ownership of ticketId, eligibility of ticket (ticketId falls between firstTicketId and firstTicketIdNextLottery), and whether ticketId falls within eligible prize bracket (between 0 and 5).

Write functions (operator/admin)

closeLottery

function closeLottery(uint256 _lotteryId) external override onlyOperator;

Closes the Open Lottery to Close state. Emits LotteryClose event.

drawFinalNumberAndMakeLotteryClaimable

    function drawFinalNumberAndMakeLotteryClaimable(uint256 _lotteryId, bool _autoInjection) external override onlyOperator nonReentrant;

Lottery must be in Close state. Draws the final Lottery number for results from randomResult, calculates the rewards for brackets after accounting for treasury fee, makes Lottery state Claimable, and transfers treasury fee to treasury address.

changeRandomNumberGenerator

    function changeRandomGenerator(address _randomGeneratorAddress) external onlyOwner;

Changes the random number generator contract address. Lottery must be Claimable.

injectFunds

function injectFunds(uint256 _lotteryId, uint256 _amount) external override onlyOwner;

Inject funds into a Lottery. Lottery must be Open.

startLottery

    function startLottery(
        uint256 _endTime,
        uint256 _priceTicketInCake,
        uint256 _discountDivisor,
        uint256[6] calldata _rewardsBreakdown,
        uint256 _treasuryFee
    ) external override onlyOperator;

Starts the Lottery, setting it to Open state. Status must be Claimable.

recoverWrongTokens

function recoverWrongTokens(address _tokenAddress, uint256 _tokenAmount) external onlyOwner;

Allows admin to recover incorrect tokens sent to address mistakenly. Cannot be CAKE tokens.

setMinAndMaxTicketPriceInCake

function recoverWrongTokens(address _tokenAddress, uint256 _tokenAmount) external onlyOwner;

Allows admin to set upper and lower limit of ticket price in CAKE value. Minimum price must be lower than maximum price.

setMaxNumberTicketsPerBuy

function setMaxNumberTicketsPerBuy(uint256 _maxNumberTicketsPerBuy) external onlyOwner;

Set max number of tickets purchasable at a time (presently 100). Max number of tickets must be higher than 0.

setOperatorAndTreasuryAndInjectorAddress

function setOperatorAndTreasuryAddresses(address _operatorAddress, address _treasuryAddress) external onlyOwner;

Sets the address of the Lottery operator.

Events (User)

TicketsPurchase

TicketsPurchase(address indexed buyer, uint256 indexed lotteryId, uint256 numberTickets);

Lottery tickets are purchased.

Emitter: buyTickets go to buyTickets

TicketsClaim

TicketsClaim(address indexed claimer, uint256 amount, uint256 indexed lotteryId, uint256 numberTickets);

Lottery tickets are claimed post-draw.

Emitter: claimTickets go to claimTickets

Events (admin)

AdminTokenRecovery

AdminTokenRecovery(address token, uint256 amount);

Admin recovers incorrect tokens from Lottery address. Emitter: recoverWrongTokens go to recoverWrongTokens

LotteryClose

LotteryClose(uint256 indexed lotteryId, uint256 firstTicketIdNextLottery);

The Lottery is closed. lotteryId is indexed and firstTicketIdNextLottery is determined by currentTicketId.

Emitter: closeLottery go to closeLottery

LotteryInjection

LotteryInjection(uint256 indexed lotteryId, uint256 amount);

Funds are injected into Lottery.

Emitter: injectFunds go to injectFunds

LotteryOpen

LotteryOpen(
        uint256 indexed lotteryId,
        uint256 startTime,
        uint256 endTime,
        uint256 priceTicketInCake,
        uint256 firstTicketId
    );

The Lottery is opened. firstTicketId is set from currentTicketId,

Emitter: startLottery go to startLottery

LotteryNumberDrawn

LotteryNumberDrawn(uint256 indexed lotteryId, uint256 finalNumber, uint256 countWinningTickets);

Lottery numbers are drawn for Lottery round.

Emitter: drawFinalNumberAndMakeLotteryClaimable go to drawFinalNumberAndMakeLotteryClaimable

NewOperatorAndTreasuryAndInjectorAddresses

NewOperatorAndTreasuryAndInjectorAddresses(address operator, address treasury);

New operator address is set.

Emitter: setOperatorAndTreasuryAndInjectorAddresses go to setOperatorAndTreasuryAndInjectorAddresses

NewRandomNumberGenerator

NewRandomGenerator(address indexed randomGenerator);

New random number generator address is set.

Emitter: changeRandomGenerator go to changeRandomGenerator