Contract 0x7Cd2C53fCCB1Fae378b5987B018f0C4cD8980ca4

 
 
Txn Hash
Method
Block
From
To
Value
0xe85d65a23414783909f614531a7f00129870bef801ec9a1e39fa9c0c4324e0c1Set Approval For...156419702022-09-29 22:27:351 day 25 mins ago0xae7789b6421520ef478f37a49e4e65abe8beebcd IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00047418 9.7132271
0x4ed6a2a2afb67c3afd0b6fdfea3e0b7a2f51947eb81acd67b28350d3f479aedbSafe Transfer Fr...156204212022-09-26 22:08:594 days 43 mins ago0x1a5ffe506b7a16cc9e4923a7efb9cd198032ae99 IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00138419 15.43589879
0xc2a433a05070a21ff7a3652aae18f3c4323ac81bb9fce2a55eb5444fb5b7aa11Set Approval For...155502662022-09-17 2:14:5913 days 20 hrs agoENS Name 40200.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00023995 4.91527596
0xe136955a55631613cfc5ca45dc7e6f383c839331747e9b69d2f7aaff6d83bb76Safe Transfer Fr...155005842022-09-09 3:56:3521 days 18 hrs agoENS Name backrooms.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00088462 11.14086871
0x796d7a67eafac6cdc1361fd2752d2a95f6871c982b60743be59dae98717b97a7Safe Transfer Fr...155005722022-09-09 3:54:0521 days 18 hrs ago0x1a5ffe506b7a16cc9e4923a7efb9cd198032ae99 IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00119354 11.70445145
0x1f8d680991f9f0be7c3edbc551ae8b99a737fc6a159f182bb1f889ff74109832Set Approval For...154999802022-09-09 1:35:4021 days 21 hrs agoENS Name southsidecity.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00064509 13.21434711
0x5aacefe84dbff6dc6a5b9bd37c6ead5f8c600fcc7edf586cdb7df87abf47c419Safe Transfer Fr...153751902022-08-20 3:13:5641 days 19 hrs agoENS Name experimentalnft.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.0006951 6.81648298
0x3c3fb746b80f27c10e5c3339b3ee72e0bdad8d00ce95d4fb3f03e0ece39bc8c3Set Approval For...153635202022-08-18 6:41:4643 days 16 hrs agoENS Name stellacat.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00034192 7.00403538
0xfeb9a59360036fd4bc41f0f1ae3716e574f03e29a8d4eb1e90551bd1ce080857Transfer From153408142022-08-14 16:22:1947 days 6 hrs ago0xe47c323387f7822948679ff72302d758a4932a75 IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00260404 29.30597704
0xcf1c32129686ead69b1181a8a166f0142a8e7902840f6efdf20b8986b901ec77Set Approval For...153135742022-08-10 9:28:3851 days 13 hrs agoENS Name matsnft.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00039719 8.13633292
0x4d04e44178170443dadb8b826cfea18aacd270e96763bd0a0deb1a6f4c06ea9cStop Sale152980362022-08-07 23:03:2453 days 23 hrs agoENS Name backrooms.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00021985 8.35866274
0xc20a5e2296faafcc728f922de966b2aa4df886af2c760727cc8eafedd1d39a73Withdraw152978432022-08-07 22:21:4254 days 31 mins agoENS Name backrooms.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00102639 15.10499547
0x2d9281d6bd3834b0cd4d64f9019a31c9205bd14582e2a9569cba3e73f7711e8cTransfer From152969682022-08-07 18:58:2254 days 3 hrs agoENS Name functionables.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00062966 7.08727929
0xa77bf66f012e7e6cab88f6665fe858c609447fa5b9a1bfdffe4474a9cacbdf2cTransfer From152969592022-08-07 18:57:1554 days 3 hrs agoENS Name functionables.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00061914 8.08867406
0x26a0a1bc84de30f001a73b027dd5d453dd97813b59588b9fef74a5437296f894Transfer From152969502022-08-07 18:55:2254 days 3 hrs agoENS Name functionables.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00063129 8.24601447
0xc3845dcabbd0834ef45a714889fc498694f08f30a8e89a81f19688b8e1e34485Transfer From152968482022-08-07 18:33:4954 days 4 hrs agoENS Name functionables.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00086001 8.67585386
0x029e2fb88453ea74808af1be9a6186cf4d7b79b8fd7b6b0fbb3cc95b01eaec29Transfer From152966932022-08-07 18:01:2254 days 4 hrs ago0x8b38e93e21c3f4ca4dd41d9f86a0515a1560cc8c IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00170431 19.80451901
0x3defd9b88e7a5196f04520ffc2dd765043f3734db97f767d07fea060352498aaMint152899332022-08-06 17:00:1155 days 5 hrs ago0x93a6d60ee0a7059d9f508f0af995581278d90e41 IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40.08 Ether0.0020389 9.8178736
0x9d0a3eae8d25cbc76a082f7856b362d1a6e03a3ba016cb7f6d906142814ef61aMint152894562022-08-06 15:12:2255 days 7 hrs agoENS Name 9184.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40.08 Ether0.00247192 12.78318654
0xa21263bbcbd47b36488f13bbdb3f4a756506f22dc8e7989dfb73fceff0b31c78Mint152893112022-08-06 14:39:1755 days 8 hrs ago0x8b38e93e21c3f4ca4dd41d9f86a0515a1560cc8c IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40.08 Ether0.00248037 11.94364826
0x073ca7dae43d3fa68a5d4d0242b379631beb732d14897ab5477d524f1065960eMint152866912022-08-06 4:45:5055 days 18 hrs agoENS Name wgmeets.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40.08 Ether0.00143215 6.89619974
0xe2d6f5acfb795cdc50be9f7d50d1962bc86b047eba805eae746503134c6bc92cMint152865792022-08-06 4:23:0355 days 18 hrs agoENS Name functionables.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40.08 Ether0.00155514 8.04218879
0x48e6350df59b35f203701a776a3cb4ecf040c0f533a5bf578d6ff2c10e140d90Transfer From152850172022-08-05 22:28:4356 days 24 mins agoENS Name backrooms.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00133097 14.9808895
0x33287bc24c7e9c710d657f6bc364a43e3da144aff345aa3989aa88ff042f3b15Mint152841582022-08-05 19:14:4756 days 3 hrs ago0xe47c323387f7822948679ff72302d758a4932a75 IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40.08 Ether0.00313643 16.21958815
0x33b3ddd92f5b2e5c5f342c556d8de29f59610786e304b091b99cddcc5865e62fTransfer From152736892022-08-04 4:15:1757 days 18 hrs agoENS Name backrooms.eth IN  0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca40 Ether0.00132717 15.79464318
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Latest 25 internal transaction
Parent Txn Hash Block From To Value
0xc20a5e2296faafcc728f922de966b2aa4df886af2c760727cc8eafedd1d39a73152978432022-08-07 22:21:4254 days 31 mins ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.532 Ether
0xc20a5e2296faafcc728f922de966b2aa4df886af2c760727cc8eafedd1d39a73152978432022-08-07 22:21:4254 days 31 mins ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.028 Ether
0x81bfac3ef231128a927f9d50f0d781506e7f61f4dad8915a16e6105a5f82cab3152704372022-08-03 16:11:3158 days 6 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.684 Ether
0x81bfac3ef231128a927f9d50f0d781506e7f61f4dad8915a16e6105a5f82cab3152704372022-08-03 16:11:3158 days 6 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.036 Ether
0x5964a281172bc001018e01be16781a30c94d01357430589881524f3c2c74769e152651052022-08-02 19:59:0759 days 2 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.152 Ether
0x5964a281172bc001018e01be16781a30c94d01357430589881524f3c2c74769e152651052022-08-02 19:59:0759 days 2 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.008 Ether
0x6f7285b5e7e630a96c80a81921a67126cf2adeba90b7fded6dc241eb1139d26b152514642022-07-31 17:02:0661 days 5 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.152 Ether
0x6f7285b5e7e630a96c80a81921a67126cf2adeba90b7fded6dc241eb1139d26b152514642022-07-31 17:02:0661 days 5 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.008 Ether
0x58e0adf38242cdf246601c35578fdd23d6dedf44d650600a03c92b3902be5d01152281722022-07-28 2:04:5664 days 20 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.304 Ether
0x58e0adf38242cdf246601c35578fdd23d6dedf44d650600a03c92b3902be5d01152281722022-07-28 2:04:5664 days 20 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.016 Ether
0x79506016ed5f52e8c28c364aa4b9ab9584312baca83903610ee5b032ee6e926f151885162022-07-21 21:53:4671 days 59 mins ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.076 Ether
0x79506016ed5f52e8c28c364aa4b9ab9584312baca83903610ee5b032ee6e926f151885162022-07-21 21:53:4671 days 59 mins ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.004 Ether
0x71089dd1bd7d453f17a65c190bbc086fba61a6f5fc23ac902e36b2c87f609b09151696642022-07-18 23:54:4773 days 22 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.152 Ether
0x71089dd1bd7d453f17a65c190bbc086fba61a6f5fc23ac902e36b2c87f609b09151696642022-07-18 23:54:4773 days 22 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.008 Ether
0x9a5c014fac92e706329291c87e9224aa0d802a750f7ffa55b3f89533482ec439151189292022-07-11 3:25:2581 days 19 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.076 Ether
0x9a5c014fac92e706329291c87e9224aa0d802a750f7ffa55b3f89533482ec439151189292022-07-11 3:25:2581 days 19 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.004 Ether
0xc0a02df38b7588d82e87b3765132f482a66b425f56bf8301777e505ba993d966150676602022-07-03 5:27:0889 days 17 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.152 Ether
0xc0a02df38b7588d82e87b3765132f482a66b425f56bf8301777e505ba993d966150676602022-07-03 5:27:0889 days 17 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.008 Ether
0x5566f958a33a478ff7233b979462ff3b5106b6559082dd193b0082c3e01ea128149737142022-06-16 14:09:58106 days 8 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.152 Ether
0x5566f958a33a478ff7233b979462ff3b5106b6559082dd193b0082c3e01ea128149737142022-06-16 14:09:58106 days 8 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.008 Ether
0x0505377d78bcf8ed4487a404dc8039530041e31379c9d7304960fd6e9d3bdbec149631542022-06-14 18:24:13108 days 4 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.152 Ether
0x0505377d78bcf8ed4487a404dc8039530041e31379c9d7304960fd6e9d3bdbec149631542022-06-14 18:24:13108 days 4 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.008 Ether
0xe1878458bd148d1686e5b58c504467aafd980cc444fde792a5ae5c0c9fee648d149346272022-06-09 20:52:20113 days 2 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.076 Ether
0xe1878458bd148d1686e5b58c504467aafd980cc444fde792a5ae5c0c9fee648d149346272022-06-09 20:52:20113 days 2 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4 0x370a695f879b665db5745de917105208a1dc61fd0.004 Ether
0x7547bfd75109da1824a4d7509043fd00e1c6bf56b6a93e81cd5ca81dae536cf3149066822022-06-05 2:48:19117 days 20 hrs ago 0x7cd2c53fccb1fae378b5987b018f0c4cd8980ca4ENS Name southsidecity.eth0.152 Ether
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Minimal Proxy Contract for 0xddda81cb8277daa757b8bddbd2d92cd77a32c313

Contract Name:
DropCollection

Compiler Version
v0.8.9+commit.e5eed63a

Optimization Enabled:
Yes with 99999 runs

Other Settings:
default evmVersion
Decompile ByteCode

Contract Source Code (Solidity Standard Json-Input format)

File 1 of 21 : DropCollection.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "@openzeppelin/contracts-upgradeable/utils/math/SafeMathUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/cryptography/MerkleProofUpgradeable.sol";
import "./BaseCollection.sol";

contract DropCollection is BaseCollection {
    event MerkleRootSet(bytes32 indexed merkleRoot);
    event TokenBaseURISet(string indexed tokenBaseURI);

    using SafeMathUpgradeable for uint256;
    using MerkleProofUpgradeable for bytes32[];

    mapping(address => uint256) private _mintCount;
    bytes32 private _merkleRoot;
    string private _tokenBaseURI;

    // Sales Parameters
    uint256 private _maxAmount;
    uint256 private _maxPerMint;
    uint256 private _maxPerWallet;
    uint256 private _price;

    // Auction Parameters
    uint256 private _startPrice;
    uint256 private _endPrice;
    uint256 private _duration;
    uint256 private _startedAt;

    // States
    bool private _presaleActive = false;
    bool private _saleActive = false;
    bool private _auctionActive = false;

    modifier onlyMintable(uint256 numberOfTokens) {
        require(numberOfTokens > 0, "Greater than 0");
        require(
            _mintCount[_msgSender()].add(numberOfTokens) <= _maxPerWallet,
            "Exceeded max: 1"
        );
        require(
            _maxAmount > 0
                ? totalSupply().add(numberOfTokens) <= _maxAmount
                : true,
            "Exceeded max: 2"
        );
        require(numberOfTokens <= _maxPerMint, "Exceeded max: 3");
        _;
    }

    function initialize(
        string memory name_,
        string memory symbol_,
        address treasury_,
        address royalty_,
        uint96 royaltyFee_
    ) public override initializer {
        __BaseCollection_init(
            name_,
            symbol_,
            treasury_,
            royalty_,
            royaltyFee_
        );
    }

    function mint(uint256 numberOfTokens)
        public
        payable
        onlyMintable(numberOfTokens)
    {
        require(!_presaleActive, "Not active: 1");
        require(_auctionActive || _saleActive, "Not active: 2");

        _purchaseMint(numberOfTokens, _msgSender());
    }

    function presaleMint(uint256 numberOfTokens, bytes32[] calldata proof)
        public
        payable
        onlyMintable(numberOfTokens)
    {
        require(_presaleActive, "Not active: 3");
        require(_merkleRoot != "", "Not active: 4");
        require(
            MerkleProofUpgradeable.verify(
                proof,
                _merkleRoot,
                keccak256(abi.encodePacked(_msgSender()))
            ),
            "Not active"
        );

        _purchaseMint(numberOfTokens, _msgSender());
    }

    function batchAirdrop(
        uint256[] calldata numberOfTokens,
        address[] calldata recipients
    ) external onlyOwner {
        require(numberOfTokens.length == recipients.length);

        for (uint256 i = 0; i < recipients.length; i++) {
            _mint(numberOfTokens[i], recipients[i]);
        }
    }

    function setMerkleRoot(bytes32 newRoot) public onlyOwner {
        _merkleRoot = newRoot;

        emit MerkleRootSet(newRoot);
    }

    function startSale(
        uint256 newMaxAmount,
        uint256 newMaxPerMint,
        uint256 newMaxPerWallet,
        uint256 newPrice,
        bool presale
    ) public onlyOwner {
        _saleActive = true;
        _presaleActive = presale;

        _maxAmount = newMaxAmount;
        _maxPerMint = newMaxPerMint;
        _maxPerWallet = newMaxPerWallet;
        _price = newPrice;
    }

    function startAuction(
        uint256 newMaxAmount,
        uint256 newMaxPerMint,
        uint256 newMaxPerWallet,
        uint256 newStartPrice,
        uint256 newEndPrice,
        uint256 newDuration,
        bool presale
    ) public onlyOwner {
        _auctionActive = true;
        _presaleActive = presale;

        _startedAt = block.timestamp;
        _maxAmount = newMaxAmount;
        _maxPerMint = newMaxPerMint;
        _maxPerWallet = newMaxPerWallet;
        _endPrice = newEndPrice;
        _startPrice = newStartPrice;
        _duration = newDuration;
    }

    function stopSale() public onlyOwner {
        _saleActive = false;
        _auctionActive = false;
        _presaleActive = false;
    }

    function setBaseURI(string memory newBaseURI) public onlyOwner {
        _tokenBaseURI = newBaseURI;

        emit TokenBaseURISet(newBaseURI);
    }

    function maxAmount() external view returns (uint256) {
        return _maxAmount;
    }

    function maxPerMint() external view returns (uint256) {
        return _maxPerMint;
    }

    function maxPerWallet() external view returns (uint256) {
        return _maxPerWallet;
    }

    function price() external view returns (uint256) {
        return _price;
    }

    function presaleActive() external view returns (bool) {
        return _presaleActive;
    }

    function saleActive() external view returns (bool) {
        return _saleActive;
    }

    function auctionActive() external view returns (bool) {
        return _auctionActive;
    }

    function auctionStartedAt() external view returns (uint256) {
        return _startedAt;
    }

    function auctionDuration() external view returns (uint256) {
        return _duration;
    }

    function auctionPrice() public view returns (uint256) {
        if ((block.timestamp - _startedAt) >= _duration) {
            return _endPrice;
        } else {
            return
                ((_duration - (block.timestamp - _startedAt)) *
                    (_startPrice - _endPrice)) /
                _duration +
                _endPrice;
        }
    }

    function _baseURI() internal view virtual override returns (string memory) {
        return _tokenBaseURI;
    }

    function _purchaseMint(uint256 numberOfTokens, address sender) internal {
        uint256 mintPrice = _auctionActive
            ? auctionPrice().mul(numberOfTokens)
            : _price.mul(numberOfTokens);
        require(mintPrice <= msg.value, "Value incorrect");

        unchecked {
            _totalRevenue = _totalRevenue.add(msg.value);
            _mintCount[sender] = _mintCount[sender].add(numberOfTokens);
        }

        _niftyKit.addFees(msg.value);
        _mint(numberOfTokens, sender);
    }

    function _mint(uint256 numberOfTokens, address sender) internal {
        for (uint256 i = 0; i < numberOfTokens; i++) {
            uint256 mintIndex = totalSupply() + 1;
            _safeMint(sender, mintIndex);
        }
    }
}

File 2 of 21 : SafeMathUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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 SafeMathUpgradeable {
    /**
     * @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 substraction 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 3 of 21 : MerkleProofUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/MerkleProof.sol)

pragma solidity ^0.8.0;

/**
 * @dev These functions deal with verification of Merkle Trees proofs.
 *
 * The proofs can be generated using the JavaScript library
 * https://github.com/miguelmota/merkletreejs[merkletreejs].
 * Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
 *
 * See `test/utils/cryptography/MerkleProof.test.js` for some examples.
 */
library MerkleProofUpgradeable {
    /**
     * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
     * defined by `root`. For this, a `proof` must be provided, containing
     * sibling hashes on the branch from the leaf to the root of the tree. Each
     * pair of leaves and each pair of pre-images are assumed to be sorted.
     */
    function verify(
        bytes32[] memory proof,
        bytes32 root,
        bytes32 leaf
    ) internal pure returns (bool) {
        return processProof(proof, leaf) == root;
    }

    /**
     * @dev Returns the rebuilt hash obtained by traversing a Merklee tree up
     * from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
     * hash matches the root of the tree. When processing the proof, the pairs
     * of leafs & pre-images are assumed to be sorted.
     *
     * _Available since v4.4._
     */
    function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {
        bytes32 computedHash = leaf;
        for (uint256 i = 0; i < proof.length; i++) {
            bytes32 proofElement = proof[i];
            if (computedHash <= proofElement) {
                // Hash(current computed hash + current element of the proof)
                computedHash = _efficientHash(computedHash, proofElement);
            } else {
                // Hash(current element of the proof + current computed hash)
                computedHash = _efficientHash(proofElement, computedHash);
            }
        }
        return computedHash;
    }

    function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {
        assembly {
            mstore(0x00, a)
            mstore(0x20, b)
            value := keccak256(0x00, 0x40)
        }
    }
}

File 4 of 21 : BaseCollection.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/math/SafeMathUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/token/ERC721/ERC721Upgradeable.sol";
import "@openzeppelin/contracts-upgradeable/token/ERC721/extensions/ERC721EnumerableUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/token/common/ERC2981Upgradeable.sol";
import "./interfaces/IBaseCollection.sol";
import "./interfaces/INiftyKit.sol";

abstract contract BaseCollection is
    ERC721Upgradeable,
    ERC721EnumerableUpgradeable,
    ERC2981Upgradeable,
    OwnableUpgradeable,
    IBaseCollection
{
    using AddressUpgradeable for address;
    using SafeMathUpgradeable for uint256;

    INiftyKit internal _niftyKit;
    address internal _treasury;
    uint256 internal _totalRevenue;

    function __BaseCollection_init(
        string memory name_,
        string memory symbol_,
        address treasury_,
        address royalty_,
        uint96 royaltyFee_
    ) internal onlyInitializing {
        __ERC721_init(name_, symbol_);
        __ERC721Enumerable_init();
        __ERC2981_init();
        __Ownable_init_unchained();

        _niftyKit = INiftyKit(_msgSender());
        _treasury = treasury_;
        _setDefaultRoyalty(royalty_, royaltyFee_);
    }

    function withdraw() external {
        require(address(this).balance > 0, "0 balance");

        uint256 balance = address(this).balance;
        uint256 fees = _niftyKit.getFees(address(this));
        _niftyKit.addFeesClaimed(fees);
        AddressUpgradeable.sendValue(payable(address(_niftyKit)), fees);
        AddressUpgradeable.sendValue(payable(_treasury), balance.sub(fees));
    }

    function setTreasury(address newTreasury) external onlyOwner {
        _treasury = newTreasury;
    }

    function setDefaultRoyalty(address receiver, uint96 feeNumerator)
        external
        onlyOwner
    {
        _setDefaultRoyalty(receiver, feeNumerator);
    }

    function setTokenRoyalty(
        uint256 tokenId,
        address receiver,
        uint96 feeNumerator
    ) external onlyOwner {
        _setTokenRoyalty(tokenId, receiver, feeNumerator);
    }

    function treasury() external view returns (address) {
        return _treasury;
    }

    function totalRevenue() external view returns (uint256) {
        return _totalRevenue;
    }

    // The following functions are overrides required by Solidity.
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    )
        internal
        virtual
        override(ERC721Upgradeable, ERC721EnumerableUpgradeable)
    {
        super._beforeTokenTransfer(from, to, tokenId);
    }

    function supportsInterface(bytes4 interfaceId)
        public
        view
        virtual
        override(
            ERC721Upgradeable,
            ERC721EnumerableUpgradeable,
            ERC2981Upgradeable
        )
        returns (bool)
    {
        return super.supportsInterface(interfaceId);
    }

    function transferOwnership(address newOwner)
        public
        override(IBaseCollection, OwnableUpgradeable)
    {
        return OwnableUpgradeable.transferOwnership(newOwner);
    }
}

File 5 of 21 : OwnableUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)

pragma solidity ^0.8.0;

import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.sol";

/**
 * @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 OwnableUpgradeable is Initializable, ContextUpgradeable {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    function __Ownable_init() internal onlyInitializing {
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal onlyInitializing {
        _transferOwnership(_msgSender());
    }

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

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

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

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

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

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[49] private __gap;
}

File 6 of 21 : AddressUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)

pragma solidity ^0.8.1;

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

        return account.code.length > 0;
    }

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

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

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

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

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

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

File 7 of 21 : ERC721Upgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/ERC721.sol)

pragma solidity ^0.8.0;

import "./IERC721Upgradeable.sol";
import "./IERC721ReceiverUpgradeable.sol";
import "./extensions/IERC721MetadataUpgradeable.sol";
import "../../utils/AddressUpgradeable.sol";
import "../../utils/ContextUpgradeable.sol";
import "../../utils/StringsUpgradeable.sol";
import "../../utils/introspection/ERC165Upgradeable.sol";
import "../../proxy/utils/Initializable.sol";

/**
 * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
 * the Metadata extension, but not including the Enumerable extension, which is available separately as
 * {ERC721Enumerable}.
 */
contract ERC721Upgradeable is Initializable, ContextUpgradeable, ERC165Upgradeable, IERC721Upgradeable, IERC721MetadataUpgradeable {
    using AddressUpgradeable for address;
    using StringsUpgradeable for uint256;

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

    // Mapping from token ID to owner address
    mapping(uint256 => address) private _owners;

    // Mapping owner address to token count
    mapping(address => uint256) private _balances;

    // Mapping from token ID to approved address
    mapping(uint256 => address) private _tokenApprovals;

    // Mapping from owner to operator approvals
    mapping(address => mapping(address => bool)) private _operatorApprovals;

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    function __ERC721_init(string memory name_, string memory symbol_) internal onlyInitializing {
        __ERC721_init_unchained(name_, symbol_);
    }

    function __ERC721_init_unchained(string memory name_, string memory symbol_) internal onlyInitializing {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165Upgradeable, IERC165Upgradeable) returns (bool) {
        return
            interfaceId == type(IERC721Upgradeable).interfaceId ||
            interfaceId == type(IERC721MetadataUpgradeable).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: balance query for the zero address");
        return _balances[owner];
    }

    /**
     * @dev See {IERC721-ownerOf}.
     */
    function ownerOf(uint256 tokenId) public view virtual override returns (address) {
        address owner = _owners[tokenId];
        require(owner != address(0), "ERC721: owner query for nonexistent token");
        return owner;
    }

    /**
     * @dev See {IERC721Metadata-name}.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev See {IERC721Metadata-symbol}.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");

        string memory baseURI = _baseURI();
        return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
    }

    /**
     * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
     * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
     * by default, can be overriden in child contracts.
     */
    function _baseURI() internal view virtual returns (string memory) {
        return "";
    }

    /**
     * @dev See {IERC721-approve}.
     */
    function approve(address to, uint256 tokenId) public virtual override {
        address owner = ERC721Upgradeable.ownerOf(tokenId);
        require(to != owner, "ERC721: approval to current owner");

        require(
            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
            "ERC721: approve caller is not owner nor approved for all"
        );

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        require(_exists(tokenId), "ERC721: approved query for nonexistent token");

        return _tokenApprovals[tokenId];
    }

    /**
     * @dev See {IERC721-setApprovalForAll}.
     */
    function setApprovalForAll(address operator, bool approved) public virtual override {
        _setApprovalForAll(_msgSender(), operator, approved);
    }

    /**
     * @dev See {IERC721-isApprovedForAll}.
     */
    function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
        return _operatorApprovals[owner][operator];
    }

    /**
     * @dev See {IERC721-transferFrom}.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        //solhint-disable-next-line max-line-length
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");

        _transfer(from, to, tokenId);
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        safeTransferFrom(from, to, tokenId, "");
    }

    /**
     * @dev See {IERC721-safeTransferFrom}.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) public virtual override {
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
        _safeTransfer(from, to, tokenId, _data);
    }

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * `_data` is additional data, it has no specified format and it is sent in call to `to`.
     *
     * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
     * implement alternative mechanisms to perform token transfer, such as signature-based.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeTransfer(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) internal virtual {
        _transfer(from, to, tokenId);
        require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
    }

    /**
     * @dev Returns whether `tokenId` exists.
     *
     * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
     *
     * Tokens start existing when they are minted (`_mint`),
     * and stop existing when they are burned (`_burn`).
     */
    function _exists(uint256 tokenId) internal view virtual returns (bool) {
        return _owners[tokenId] != address(0);
    }

    /**
     * @dev Returns whether `spender` is allowed to manage `tokenId`.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
        require(_exists(tokenId), "ERC721: operator query for nonexistent token");
        address owner = ERC721Upgradeable.ownerOf(tokenId);
        return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));
    }

    /**
     * @dev Safely mints `tokenId` and transfers it to `to`.
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function _safeMint(address to, uint256 tokenId) internal virtual {
        _safeMint(to, tokenId, "");
    }

    /**
     * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
     * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
     */
    function _safeMint(
        address to,
        uint256 tokenId,
        bytes memory _data
    ) internal virtual {
        _mint(to, tokenId);
        require(
            _checkOnERC721Received(address(0), to, tokenId, _data),
            "ERC721: transfer to non ERC721Receiver implementer"
        );
    }

    /**
     * @dev Mints `tokenId` and transfers it to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
     *
     * Requirements:
     *
     * - `tokenId` must not exist.
     * - `to` cannot be the zero address.
     *
     * Emits a {Transfer} event.
     */
    function _mint(address to, uint256 tokenId) internal virtual {
        require(to != address(0), "ERC721: mint to the zero address");
        require(!_exists(tokenId), "ERC721: token already minted");

        _beforeTokenTransfer(address(0), to, tokenId);

        _balances[to] += 1;
        _owners[tokenId] = to;

        emit Transfer(address(0), to, tokenId);

        _afterTokenTransfer(address(0), to, tokenId);
    }

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     *
     * Emits a {Transfer} event.
     */
    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721Upgradeable.ownerOf(tokenId);

        _beforeTokenTransfer(owner, address(0), tokenId);

        // Clear approvals
        _approve(address(0), tokenId);

        _balances[owner] -= 1;
        delete _owners[tokenId];

        emit Transfer(owner, address(0), tokenId);

        _afterTokenTransfer(owner, address(0), tokenId);
    }

    /**
     * @dev Transfers `tokenId` from `from` to `to`.
     *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     *
     * Emits a {Transfer} event.
     */
    function _transfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {
        require(ERC721Upgradeable.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
        require(to != address(0), "ERC721: transfer to the zero address");

        _beforeTokenTransfer(from, to, tokenId);

        // Clear approvals from the previous owner
        _approve(address(0), tokenId);

        _balances[from] -= 1;
        _balances[to] += 1;
        _owners[tokenId] = to;

        emit Transfer(from, to, tokenId);

        _afterTokenTransfer(from, to, tokenId);
    }

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits a {Approval} event.
     */
    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721Upgradeable.ownerOf(tokenId), to, tokenId);
    }

    /**
     * @dev Approve `operator` to operate on all of `owner` tokens
     *
     * Emits a {ApprovalForAll} event.
     */
    function _setApprovalForAll(
        address owner,
        address operator,
        bool approved
    ) internal virtual {
        require(owner != operator, "ERC721: approve to caller");
        _operatorApprovals[owner][operator] = approved;
        emit ApprovalForAll(owner, operator, approved);
    }

    /**
     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
     * The call is not executed if the target address is not a contract.
     *
     * @param from address representing the previous owner of the given token ID
     * @param to target address that will receive the tokens
     * @param tokenId uint256 ID of the token to be transferred
     * @param _data bytes optional data to send along with the call
     * @return bool whether the call correctly returned the expected magic value
     */
    function _checkOnERC721Received(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) private returns (bool) {
        if (to.isContract()) {
            try IERC721ReceiverUpgradeable(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
                return retval == IERC721ReceiverUpgradeable.onERC721Received.selector;
            } catch (bytes memory reason) {
                if (reason.length == 0) {
                    revert("ERC721: transfer to non ERC721Receiver implementer");
                } else {
                    assembly {
                        revert(add(32, reason), mload(reason))
                    }
                }
            }
        } else {
            return true;
        }
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
     * transferred to `to`.
     * - When `from` is zero, `tokenId` will be minted for `to`.
     * - When `to` is zero, ``from``'s `tokenId` will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[44] private __gap;
}

File 8 of 21 : ERC721EnumerableUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/ERC721Enumerable.sol)

pragma solidity ^0.8.0;

import "../ERC721Upgradeable.sol";
import "./IERC721EnumerableUpgradeable.sol";
import "../../../proxy/utils/Initializable.sol";

/**
 * @dev This implements an optional extension of {ERC721} defined in the EIP that adds
 * enumerability of all the token ids in the contract as well as all token ids owned by each
 * account.
 */
abstract contract ERC721EnumerableUpgradeable is Initializable, ERC721Upgradeable, IERC721EnumerableUpgradeable {
    function __ERC721Enumerable_init() internal onlyInitializing {
    }

    function __ERC721Enumerable_init_unchained() internal onlyInitializing {
    }
    // Mapping from owner to list of owned token IDs
    mapping(address => mapping(uint256 => uint256)) private _ownedTokens;

    // Mapping from token ID to index of the owner tokens list
    mapping(uint256 => uint256) private _ownedTokensIndex;

    // Array with all token ids, used for enumeration
    uint256[] private _allTokens;

    // Mapping from token id to position in the allTokens array
    mapping(uint256 => uint256) private _allTokensIndex;

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165Upgradeable, ERC721Upgradeable) returns (bool) {
        return interfaceId == type(IERC721EnumerableUpgradeable).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
        require(index < ERC721Upgradeable.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
        return _ownedTokens[owner][index];
    }

    /**
     * @dev See {IERC721Enumerable-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _allTokens.length;
    }

    /**
     * @dev See {IERC721Enumerable-tokenByIndex}.
     */
    function tokenByIndex(uint256 index) public view virtual override returns (uint256) {
        require(index < ERC721EnumerableUpgradeable.totalSupply(), "ERC721Enumerable: global index out of bounds");
        return _allTokens[index];
    }

    /**
     * @dev Hook that is called before any token transfer. This includes minting
     * and burning.
     *
     * Calling conditions:
     *
     * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
     * transferred to `to`.
     * - When `from` is zero, `tokenId` will be minted for `to`.
     * - When `to` is zero, ``from``'s `tokenId` will be burned.
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual override {
        super._beforeTokenTransfer(from, to, tokenId);

        if (from == address(0)) {
            _addTokenToAllTokensEnumeration(tokenId);
        } else if (from != to) {
            _removeTokenFromOwnerEnumeration(from, tokenId);
        }
        if (to == address(0)) {
            _removeTokenFromAllTokensEnumeration(tokenId);
        } else if (to != from) {
            _addTokenToOwnerEnumeration(to, tokenId);
        }
    }

    /**
     * @dev Private function to add a token to this extension's ownership-tracking data structures.
     * @param to address representing the new owner of the given token ID
     * @param tokenId uint256 ID of the token to be added to the tokens list of the given address
     */
    function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
        uint256 length = ERC721Upgradeable.balanceOf(to);
        _ownedTokens[to][length] = tokenId;
        _ownedTokensIndex[tokenId] = length;
    }

    /**
     * @dev Private function to add a token to this extension's token tracking data structures.
     * @param tokenId uint256 ID of the token to be added to the tokens list
     */
    function _addTokenToAllTokensEnumeration(uint256 tokenId) private {
        _allTokensIndex[tokenId] = _allTokens.length;
        _allTokens.push(tokenId);
    }

    /**
     * @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
     * while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
     * gas optimizations e.g. when performing a transfer operation (avoiding double writes).
     * This has O(1) time complexity, but alters the order of the _ownedTokens array.
     * @param from address representing the previous owner of the given token ID
     * @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
     */
    function _removeTokenFromOwnerEnumeration(address from, uint256 tokenId) private {
        // To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and
        // then delete the last slot (swap and pop).

        uint256 lastTokenIndex = ERC721Upgradeable.balanceOf(from) - 1;
        uint256 tokenIndex = _ownedTokensIndex[tokenId];

        // When the token to delete is the last token, the swap operation is unnecessary
        if (tokenIndex != lastTokenIndex) {
            uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];

            _ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
            _ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
        }

        // This also deletes the contents at the last position of the array
        delete _ownedTokensIndex[tokenId];
        delete _ownedTokens[from][lastTokenIndex];
    }

    /**
     * @dev Private function to remove a token from this extension's token tracking data structures.
     * This has O(1) time complexity, but alters the order of the _allTokens array.
     * @param tokenId uint256 ID of the token to be removed from the tokens list
     */
    function _removeTokenFromAllTokensEnumeration(uint256 tokenId) private {
        // To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and
        // then delete the last slot (swap and pop).

        uint256 lastTokenIndex = _allTokens.length - 1;
        uint256 tokenIndex = _allTokensIndex[tokenId];

        // When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so
        // rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding
        // an 'if' statement (like in _removeTokenFromOwnerEnumeration)
        uint256 lastTokenId = _allTokens[lastTokenIndex];

        _allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
        _allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index

        // This also deletes the contents at the last position of the array
        delete _allTokensIndex[tokenId];
        _allTokens.pop();
    }

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[46] private __gap;
}

File 9 of 21 : ERC2981Upgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/common/ERC2981.sol)

pragma solidity ^0.8.0;

import "../../interfaces/IERC2981Upgradeable.sol";
import "../../utils/introspection/ERC165Upgradeable.sol";
import "../../proxy/utils/Initializable.sol";

/**
 * @dev Implementation of the NFT Royalty Standard, a standardized way to retrieve royalty payment information.
 *
 * Royalty information can be specified globally for all token ids via {_setDefaultRoyalty}, and/or individually for
 * specific token ids via {_setTokenRoyalty}. The latter takes precedence over the first.
 *
 * Royalty is specified as a fraction of sale price. {_feeDenominator} is overridable but defaults to 10000, meaning the
 * fee is specified in basis points by default.
 *
 * IMPORTANT: ERC-2981 only specifies a way to signal royalty information and does not enforce its payment. See
 * https://eips.ethereum.org/EIPS/eip-2981#optional-royalty-payments[Rationale] in the EIP. Marketplaces are expected to
 * voluntarily pay royalties together with sales, but note that this standard is not yet widely supported.
 *
 * _Available since v4.5._
 */
abstract contract ERC2981Upgradeable is Initializable, IERC2981Upgradeable, ERC165Upgradeable {
    function __ERC2981_init() internal onlyInitializing {
    }

    function __ERC2981_init_unchained() internal onlyInitializing {
    }
    struct RoyaltyInfo {
        address receiver;
        uint96 royaltyFraction;
    }

    RoyaltyInfo private _defaultRoyaltyInfo;
    mapping(uint256 => RoyaltyInfo) private _tokenRoyaltyInfo;

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165Upgradeable, ERC165Upgradeable) returns (bool) {
        return interfaceId == type(IERC2981Upgradeable).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @inheritdoc IERC2981Upgradeable
     */
    function royaltyInfo(uint256 _tokenId, uint256 _salePrice)
        external
        view
        virtual
        override
        returns (address, uint256)
    {
        RoyaltyInfo memory royalty = _tokenRoyaltyInfo[_tokenId];

        if (royalty.receiver == address(0)) {
            royalty = _defaultRoyaltyInfo;
        }

        uint256 royaltyAmount = (_salePrice * royalty.royaltyFraction) / _feeDenominator();

        return (royalty.receiver, royaltyAmount);
    }

    /**
     * @dev The denominator with which to interpret the fee set in {_setTokenRoyalty} and {_setDefaultRoyalty} as a
     * fraction of the sale price. Defaults to 10000 so fees are expressed in basis points, but may be customized by an
     * override.
     */
    function _feeDenominator() internal pure virtual returns (uint96) {
        return 10000;
    }

    /**
     * @dev Sets the royalty information that all ids in this contract will default to.
     *
     * Requirements:
     *
     * - `receiver` cannot be the zero address.
     * - `feeNumerator` cannot be greater than the fee denominator.
     */
    function _setDefaultRoyalty(address receiver, uint96 feeNumerator) internal virtual {
        require(feeNumerator <= _feeDenominator(), "ERC2981: royalty fee will exceed salePrice");
        require(receiver != address(0), "ERC2981: invalid receiver");

        _defaultRoyaltyInfo = RoyaltyInfo(receiver, feeNumerator);
    }

    /**
     * @dev Removes default royalty information.
     */
    function _deleteDefaultRoyalty() internal virtual {
        delete _defaultRoyaltyInfo;
    }

    /**
     * @dev Sets the royalty information for a specific token id, overriding the global default.
     *
     * Requirements:
     *
     * - `tokenId` must be already minted.
     * - `receiver` cannot be the zero address.
     * - `feeNumerator` cannot be greater than the fee denominator.
     */
    function _setTokenRoyalty(
        uint256 tokenId,
        address receiver,
        uint96 feeNumerator
    ) internal virtual {
        require(feeNumerator <= _feeDenominator(), "ERC2981: royalty fee will exceed salePrice");
        require(receiver != address(0), "ERC2981: Invalid parameters");

        _tokenRoyaltyInfo[tokenId] = RoyaltyInfo(receiver, feeNumerator);
    }

    /**
     * @dev Resets royalty information for the token id back to the global default.
     */
    function _resetTokenRoyalty(uint256 tokenId) internal virtual {
        delete _tokenRoyaltyInfo[tokenId];
    }

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[48] private __gap;
}

File 10 of 21 : IBaseCollection.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

interface IBaseCollection {
    /**
     * @dev Contract upgradeable initializer
     */
    function initialize(
        string memory,
        string memory,
        address,
        address,
        uint96
    ) external;

    /**
     * @dev part of Ownable
     */
    function transferOwnership(address) external;
}

File 11 of 21 : INiftyKit.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

interface INiftyKit {
    /**
     * @dev Emitted when collection is created
     */
    event CollectionCreated(address indexed collectionAddress);

    /**
     * @dev Returns the commission amount.
     */
    function commission(uint256 amount) external view returns (uint256);

    /**
     * @dev Add fees from Collection
     */
    function addFees(uint256 amount) external;

    /**
     * @dev Add fees claimed by the Collection
     */
    function addFeesClaimed(uint256 amount) external;

    /**
     * @dev Get fees accrued by the account
     */
    function getFees(address account) external view returns (uint256);
}

File 12 of 21 : ContextUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.sol";

/**
 * @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 ContextUpgradeable is Initializable {
    function __Context_init() internal onlyInitializing {
    }

    function __Context_init_unchained() internal onlyInitializing {
    }
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

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

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[50] private __gap;
}

File 13 of 21 : Initializable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (proxy/utils/Initializable.sol)

pragma solidity ^0.8.0;

import "../../utils/AddressUpgradeable.sol";

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 *
 * [CAUTION]
 * ====
 * Avoid leaving a contract uninitialized.
 *
 * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
 * contract, which may impact the proxy. To initialize the implementation contract, you can either invoke the
 * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
 *
 * [.hljs-theme-light.nopadding]
 * ```
 * /// @custom:oz-upgrades-unsafe-allow constructor
 * constructor() initializer {}
 * ```
 * ====
 */
abstract contract Initializable {
    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        // If the contract is initializing we ignore whether _initialized is set in order to support multiple
        // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
        // contract may have been reentered.
        require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }

    /**
     * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
     * {initializer} modifier, directly or indirectly.
     */
    modifier onlyInitializing() {
        require(_initializing, "Initializable: contract is not initializing");
        _;
    }

    function _isConstructor() private view returns (bool) {
        return !AddressUpgradeable.isContract(address(this));
    }
}

File 14 of 21 : IERC721Upgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

import "../../utils/introspection/IERC165Upgradeable.sol";

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721Upgradeable is IERC165Upgradeable {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
     */
    event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);

    /**
     * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
     */
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    /**
     * @dev Returns the number of tokens in ``owner``'s account.
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    /**
     * @dev Returns the owner of the `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function ownerOf(uint256 tokenId) external view returns (address owner);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes calldata data
    ) external;
}

File 15 of 21 : IERC721ReceiverUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721ReceiverUpgradeable {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

File 16 of 21 : IERC721MetadataUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC721Upgradeable.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721MetadataUpgradeable is IERC721Upgradeable {
    /**
     * @dev Returns the token collection name.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the token collection symbol.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
     */
    function tokenURI(uint256 tokenId) external view returns (string memory);
}

File 17 of 21 : StringsUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)

pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library StringsUpgradeable {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }
}

File 18 of 21 : ERC165Upgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

pragma solidity ^0.8.0;

import "./IERC165Upgradeable.sol";
import "../../proxy/utils/Initializable.sol";

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
 * for the additional interface id that will be supported. For example:
 *
 * ```solidity
 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
 * }
 * ```
 *
 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
 */
abstract contract ERC165Upgradeable is Initializable, IERC165Upgradeable {
    function __ERC165_init() internal onlyInitializing {
    }

    function __ERC165_init_unchained() internal onlyInitializing {
    }
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165Upgradeable).interfaceId;
    }

    /**
     * @dev This empty reserved space is put in place to allow future versions to add new
     * variables without shifting down storage in the inheritance chain.
     * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
     */
    uint256[50] private __gap;
}

File 19 of 21 : IERC165Upgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165Upgradeable {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

File 20 of 21 : IERC721EnumerableUpgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/extensions/IERC721Enumerable.sol)

pragma solidity ^0.8.0;

import "../IERC721Upgradeable.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721EnumerableUpgradeable is IERC721Upgradeable {
    /**
     * @dev Returns the total amount of tokens stored by the contract.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns a token ID owned by `owner` at a given `index` of its token list.
     * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256);

    /**
     * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
     * Use along with {totalSupply} to enumerate all tokens.
     */
    function tokenByIndex(uint256 index) external view returns (uint256);
}

File 21 of 21 : IERC2981Upgradeable.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (interfaces/IERC2981.sol)

pragma solidity ^0.8.0;

import "../utils/introspection/IERC165Upgradeable.sol";

/**
 * @dev Interface for the NFT Royalty Standard.
 *
 * A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal
 * support for royalty payments across all NFT marketplaces and ecosystem participants.
 *
 * _Available since v4.5._
 */
interface IERC2981Upgradeable is IERC165Upgradeable {
    /**
     * @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of
     * exchange. The royalty amount is denominated and should be payed in that same unit of exchange.
     */
    function royaltyInfo(uint256 tokenId, uint256 salePrice)
        external
        view
        returns (address receiver, uint256 royaltyAmount);
}

Settings
{
  "optimizer": {
    "enabled": true,
    "runs": 99999
  },
  "outputSelection": {
    "*": {
      "*": [
        "evm.bytecode",
        "evm.deployedBytecode",
        "devdoc",
        "userdoc",
        "metadata",
        "abi"
      ]
    }
  },
  "metadata": {
    "useLiteralContent": true
  },
  "libraries": {}
}

Contract ABI

[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"approved","type":"address"},{"indexed":true,"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"operator","type":"address"},{"indexed":false,"internalType":"bool","name":"approved","type":"bool"}],"name":"ApprovalForAll","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"merkleRoot","type":"bytes32"}],"name":"MerkleRootSet","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"string","name":"tokenBaseURI","type":"string"}],"name":"TokenBaseURISet","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"from","type":"address"},{"indexed":true,"internalType":"address","name":"to","type":"address"},{"indexed":true,"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"Transfer","type":"event"},{"inputs":[{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"approve","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"auctionActive","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"auctionDuration","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"auctionPrice","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"auctionStartedAt","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"}],"name":"balanceOf","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256[]","name":"numberOfTokens","type":"uint256[]"},{"internalType":"address[]","name":"recipients","type":"address[]"}],"name":"batchAirdrop","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"getApproved","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"string","name":"name_","type":"string"},{"internalType":"string","name":"symbol_","type":"string"},{"internalType":"address","name":"treasury_","type":"address"},{"internalType":"address","name":"royalty_","type":"address"},{"internalType":"uint96","name":"royaltyFee_","type":"uint96"}],"name":"initialize","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"address","name":"operator","type":"address"}],"name":"isApprovedForAll","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"maxAmount","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"maxPerMint","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"maxPerWallet","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"numberOfTokens","type":"uint256"}],"name":"mint","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"name","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"ownerOf","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"presaleActive","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"numberOfTokens","type":"uint256"},{"internalType":"bytes32[]","name":"proof","type":"bytes32[]"}],"name":"presaleMint","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"price","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_tokenId","type":"uint256"},{"internalType":"uint256","name":"_salePrice","type":"uint256"}],"name":"royaltyInfo","outputs":[{"internalType":"address","name":"","type":"address"},{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"safeTransferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"safeTransferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"saleActive","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"operator","type":"address"},{"internalType":"bool","name":"approved","type":"bool"}],"name":"setApprovalForAll","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"string","name":"newBaseURI","type":"string"}],"name":"setBaseURI","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"receiver","type":"address"},{"internalType":"uint96","name":"feeNumerator","type":"uint96"}],"name":"setDefaultRoyalty","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes32","name":"newRoot","type":"bytes32"}],"name":"setMerkleRoot","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"},{"internalType":"address","name":"receiver","type":"address"},{"internalType":"uint96","name":"feeNumerator","type":"uint96"}],"name":"setTokenRoyalty","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newTreasury","type":"address"}],"name":"setTreasury","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"newMaxAmount","type":"uint256"},{"internalType":"uint256","name":"newMaxPerMint","type":"uint256"},{"internalType":"uint256","name":"newMaxPerWallet","type":"uint256"},{"internalType":"uint256","name":"newStartPrice","type":"uint256"},{"internalType":"uint256","name":"newEndPrice","type":"uint256"},{"internalType":"uint256","name":"newDuration","type":"uint256"},{"internalType":"bool","name":"presale","type":"bool"}],"name":"startAuction","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"newMaxAmount","type":"uint256"},{"internalType":"uint256","name":"newMaxPerMint","type":"uint256"},{"internalType":"uint256","name":"newMaxPerWallet","type":"uint256"},{"internalType":"uint256","name":"newPrice","type":"uint256"},{"internalType":"bool","name":"presale","type":"bool"}],"name":"startSale","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"stopSale","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes4","name":"interfaceId","type":"bytes4"}],"name":"supportsInterface","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"symbol","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"index","type":"uint256"}],"name":"tokenByIndex","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"uint256","name":"index","type":"uint256"}],"name":"tokenOfOwnerByIndex","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"tokenURI","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"totalRevenue","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"totalSupply","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"tokenId","type":"uint256"}],"name":"transferFrom","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"treasury","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"withdraw","outputs":[],"stateMutability":"nonpayable","type":"function"}]

Block Transaction Difficulty Gas Used Reward
Block Uncle Number Difficulty Gas Used Reward
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