ETH Price: $2,497.59 (-0.49%)
Gas: 1.91 Gwei

Transaction Decoder

Block:
20514642 at Aug-12-2024 07:32:23 PM +UTC
Transaction Fee:
0.000285335375451318 ETH $0.71
Gas Used:
55,938 Gas / 5.100922011 Gwei

Emitted Events:

158 SuperRareV2.AddToWhitelist( _newAddress=0x8Cf84e60...e2984C817 )

Account State Difference:

  Address   Before After State Difference Code
(beaverbuild)
15.386342359803052128 Eth15.386451998283052128 Eth0.00010963848
0xb932a70A...7f75Fb9e0
0xc1920B53...f7F8f788A
0.323861183248005117 Eth
Nonce: 2078
0.323575847872553799 Eth
Nonce: 2079
0.000285335375451318

Execution Trace

SuperRareAdmin.addToWhitelist( _newAddress=0x8Cf84e6069fA1bdFb6db0be667E762de2984C817 )
  • SuperRareV2.addToWhitelist( _newAddress=0x8Cf84e6069fA1bdFb6db0be667E762de2984C817 )
    File 1 of 2: SuperRareAdmin
    // SPDX-License-Identifier: MIT
    pragma solidity 0.7.3;
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/access/AccessControl.sol";
    contract SuperRareAdmin is Ownable, AccessControl {
        bytes32 public constant SUPER_RARE_WHITELIST_ROLE =
            keccak256("SUPER_RARE_WHITELIST_ROLE");
        address public superRareV2Contract;
        constructor(address _superRareV2Contract) {
            superRareV2Contract = _superRareV2Contract;
            _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
        }
        function addToWhitelist(address _newAddress) external {
            require(
                hasRole(SUPER_RARE_WHITELIST_ROLE, msg.sender),
                "doesnt have whitelist role"
            );
            (bool success, bytes memory data) = superRareV2Contract.call(
                abi.encodeWithSignature("addToWhitelist(address)", _newAddress)
            );
            require(success, string(data));
            return;
        }
        function removeFromWhitelist(address _removedAddress) external {
            require(
                hasRole(SUPER_RARE_WHITELIST_ROLE, msg.sender),
                "doesnt have whitelist role"
            );
            (bool success, bytes memory data) = superRareV2Contract.call(
                abi.encodeWithSignature(
                    "removeFromWhitelist(address)",
                    _removedAddress
                )
            );
            require(success, string(data));
            return;
        }
        function transferOwnershipOfSuperRareV2(address _newOwner)
            external
            onlyOwner
        {
            (bool success, bytes memory data) = superRareV2Contract.call(
                abi.encodeWithSignature("transferOwnership(address)", _newOwner)
            );
            require(success, string(data));
            return;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.7.0;
    import "../utils/Context.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 Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), 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 {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.7.0;
    import "../utils/EnumerableSet.sol";
    import "../utils/Address.sol";
    import "../utils/Context.sol";
    /**
     * @dev Contract module that allows children to implement role-based access
     * control mechanisms.
     *
     * Roles are referred to by their `bytes32` identifier. These should be exposed
     * in the external API and be unique. The best way to achieve this is by
     * using `public constant` hash digests:
     *
     * ```
     * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
     * ```
     *
     * Roles can be used to represent a set of permissions. To restrict access to a
     * function call, use {hasRole}:
     *
     * ```
     * function foo() public {
     *     require(hasRole(MY_ROLE, msg.sender));
     *     ...
     * }
     * ```
     *
     * Roles can be granted and revoked dynamically via the {grantRole} and
     * {revokeRole} functions. Each role has an associated admin role, and only
     * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
     *
     * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
     * that only accounts with this role will be able to grant or revoke other
     * roles. More complex role relationships can be created by using
     * {_setRoleAdmin}.
     *
     * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
     * grant and revoke this role. Extra precautions should be taken to secure
     * accounts that have been granted it.
     */
    abstract contract AccessControl is Context {
        using EnumerableSet for EnumerableSet.AddressSet;
        using Address for address;
        struct RoleData {
            EnumerableSet.AddressSet members;
            bytes32 adminRole;
        }
        mapping (bytes32 => RoleData) private _roles;
        bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
        /**
         * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
         *
         * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
         * {RoleAdminChanged} not being emitted signaling this.
         *
         * _Available since v3.1._
         */
        event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
        /**
         * @dev Emitted when `account` is granted `role`.
         *
         * `sender` is the account that originated the contract call, an admin role
         * bearer except when using {_setupRole}.
         */
        event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Emitted when `account` is revoked `role`.
         *
         * `sender` is the account that originated the contract call:
         *   - if using `revokeRole`, it is the admin role bearer
         *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
         */
        event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
        /**
         * @dev Returns `true` if `account` has been granted `role`.
         */
        function hasRole(bytes32 role, address account) public view returns (bool) {
            return _roles[role].members.contains(account);
        }
        /**
         * @dev Returns the number of accounts that have `role`. Can be used
         * together with {getRoleMember} to enumerate all bearers of a role.
         */
        function getRoleMemberCount(bytes32 role) public view returns (uint256) {
            return _roles[role].members.length();
        }
        /**
         * @dev Returns one of the accounts that have `role`. `index` must be a
         * value between 0 and {getRoleMemberCount}, non-inclusive.
         *
         * Role bearers are not sorted in any particular way, and their ordering may
         * change at any point.
         *
         * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
         * you perform all queries on the same block. See the following
         * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
         * for more information.
         */
        function getRoleMember(bytes32 role, uint256 index) public view returns (address) {
            return _roles[role].members.at(index);
        }
        /**
         * @dev Returns the admin role that controls `role`. See {grantRole} and
         * {revokeRole}.
         *
         * To change a role's admin, use {_setRoleAdmin}.
         */
        function getRoleAdmin(bytes32 role) public view returns (bytes32) {
            return _roles[role].adminRole;
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function grantRole(bytes32 role, address account) public virtual {
            require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to grant");
            _grantRole(role, account);
        }
        /**
         * @dev Revokes `role` from `account`.
         *
         * If `account` had been granted `role`, emits a {RoleRevoked} event.
         *
         * Requirements:
         *
         * - the caller must have ``role``'s admin role.
         */
        function revokeRole(bytes32 role, address account) public virtual {
            require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to revoke");
            _revokeRole(role, account);
        }
        /**
         * @dev Revokes `role` from the calling account.
         *
         * Roles are often managed via {grantRole} and {revokeRole}: this function's
         * purpose is to provide a mechanism for accounts to lose their privileges
         * if they are compromised (such as when a trusted device is misplaced).
         *
         * If the calling account had been granted `role`, emits a {RoleRevoked}
         * event.
         *
         * Requirements:
         *
         * - the caller must be `account`.
         */
        function renounceRole(bytes32 role, address account) public virtual {
            require(account == _msgSender(), "AccessControl: can only renounce roles for self");
            _revokeRole(role, account);
        }
        /**
         * @dev Grants `role` to `account`.
         *
         * If `account` had not been already granted `role`, emits a {RoleGranted}
         * event. Note that unlike {grantRole}, this function doesn't perform any
         * checks on the calling account.
         *
         * [WARNING]
         * ====
         * This function should only be called from the constructor when setting
         * up the initial roles for the system.
         *
         * Using this function in any other way is effectively circumventing the admin
         * system imposed by {AccessControl}.
         * ====
         */
        function _setupRole(bytes32 role, address account) internal virtual {
            _grantRole(role, account);
        }
        /**
         * @dev Sets `adminRole` as ``role``'s admin role.
         *
         * Emits a {RoleAdminChanged} event.
         */
        function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
            emit RoleAdminChanged(role, _roles[role].adminRole, adminRole);
            _roles[role].adminRole = adminRole;
        }
        function _grantRole(bytes32 role, address account) private {
            if (_roles[role].members.add(account)) {
                emit RoleGranted(role, account, _msgSender());
            }
        }
        function _revokeRole(bytes32 role, address account) private {
            if (_roles[role].members.remove(account)) {
                emit RoleRevoked(role, account, _msgSender());
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.7.0;
    /**
     * @dev Library for managing
     * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
     * types.
     *
     * Sets have the following properties:
     *
     * - Elements are added, removed, and checked for existence in constant time
     * (O(1)).
     * - Elements are enumerated in O(n). No guarantees are made on the ordering.
     *
     * ```
     * contract Example {
     *     // Add the library methods
     *     using EnumerableSet for EnumerableSet.AddressSet;
     *
     *     // Declare a set state variable
     *     EnumerableSet.AddressSet private mySet;
     * }
     * ```
     *
     * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
     * and `uint256` (`UintSet`) are supported.
     */
    library EnumerableSet {
        // To implement this library for multiple types with as little code
        // repetition as possible, we write it in terms of a generic Set type with
        // bytes32 values.
        // The Set implementation uses private functions, and user-facing
        // implementations (such as AddressSet) are just wrappers around the
        // underlying Set.
        // This means that we can only create new EnumerableSets for types that fit
        // in bytes32.
        struct Set {
            // Storage of set values
            bytes32[] _values;
            // Position of the value in the `values` array, plus 1 because index 0
            // means a value is not in the set.
            mapping (bytes32 => uint256) _indexes;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function _add(Set storage set, bytes32 value) private returns (bool) {
            if (!_contains(set, value)) {
                set._values.push(value);
                // The value is stored at length-1, but we add 1 to all indexes
                // and use 0 as a sentinel value
                set._indexes[value] = set._values.length;
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function _remove(Set storage set, bytes32 value) private returns (bool) {
            // We read and store the value's index to prevent multiple reads from the same storage slot
            uint256 valueIndex = set._indexes[value];
            if (valueIndex != 0) { // Equivalent to contains(set, value)
                // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                // the array, and then remove the last element (sometimes called as 'swap and pop').
                // This modifies the order of the array, as noted in {at}.
                uint256 toDeleteIndex = valueIndex - 1;
                uint256 lastIndex = set._values.length - 1;
                // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
                // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
                bytes32 lastvalue = set._values[lastIndex];
                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastvalue;
                // Update the index for the moved value
                set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based
                // Delete the slot where the moved value was stored
                set._values.pop();
                // Delete the index for the deleted slot
                delete set._indexes[value];
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function _contains(Set storage set, bytes32 value) private view returns (bool) {
            return set._indexes[value] != 0;
        }
        /**
         * @dev Returns the number of values on the set. O(1).
         */
        function _length(Set storage set) private view returns (uint256) {
            return set._values.length;
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function _at(Set storage set, uint256 index) private view returns (bytes32) {
            require(set._values.length > index, "EnumerableSet: index out of bounds");
            return set._values[index];
        }
        // Bytes32Set
        struct Bytes32Set {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _add(set._inner, value);
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _remove(set._inner, value);
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
            return _contains(set._inner, value);
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(Bytes32Set storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
            return _at(set._inner, index);
        }
        // AddressSet
        struct AddressSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(AddressSet storage set, address value) internal returns (bool) {
            return _add(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(AddressSet storage set, address value) internal returns (bool) {
            return _remove(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(AddressSet storage set, address value) internal view returns (bool) {
            return _contains(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(AddressSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function at(AddressSet storage set, uint256 index) internal view returns (address) {
            return address(uint160(uint256(_at(set._inner, index))));
        }
        // UintSet
        struct UintSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(UintSet storage set, uint256 value) internal returns (bool) {
            return _add(set._inner, bytes32(value));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(UintSet storage set, uint256 value) internal returns (bool) {
            return _remove(set._inner, bytes32(value));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(UintSet storage set, uint256 value) internal view returns (bool) {
            return _contains(set._inner, bytes32(value));
        }
        /**
         * @dev Returns the number of values on the set. O(1).
         */
        function length(UintSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function at(UintSet storage set, uint256 index) internal view returns (uint256) {
            return uint256(_at(set._inner, index));
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity ^0.7.0;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            // solhint-disable-next-line no-inline-assembly
            assembly { size := extcodesize(account) }
            return size > 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");
            // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
            (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");
            // solhint-disable-next-line avoid-low-level-calls
            (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");
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, bytes memory returndata) = target.staticcall(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private 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
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    

    File 2 of 2: SuperRareV2
    pragma solidity ^0.4.24;
    
    /**
     * @title SafeMath
     * @dev Math operations with safety checks that revert on error
     */
    library SafeMath {
    
      /**
      * @dev Multiplies two numbers, reverts on overflow.
      */
      function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
        if (a == 0) {
          return 0;
        }
    
        uint256 c = a * b;
        require(c / a == b);
    
        return c;
      }
    
      /**
      * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
      */
      function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0); // Solidity only automatically asserts when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
    
        return c;
      }
    
      /**
      * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
      */
      function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;
    
        return c;
      }
    
      /**
      * @dev Adds two numbers, reverts on overflow.
      */
      function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);
    
        return c;
      }
    
      /**
      * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
      * reverts when dividing by zero.
      */
      function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0);
        return a % b;
      }
    }
    
    interface IERC165 {
    
      /**
       * @notice Query if a contract implements an interface
       * @param interfaceId The interface identifier, as specified in ERC-165
       * @dev Interface identification is specified in ERC-165. This function
       * uses less than 30,000 gas.
       */
      function supportsInterface(bytes4 interfaceId)
        external
        view
        returns (bool);
    }
    
    interface ISuperRare {
      /**
       * @notice A descriptive name for a collection of NFTs in this contract
       */
      function name() external pure returns (string _name);
    
      /**
       * @notice An abbreviated name for NFTs in this contract
       */
      function symbol() external pure returns (string _symbol);
    
      /** 
       * @dev Returns whether the creator is whitelisted
       * @param _creator address to check
       * @return bool 
       */
      function isWhitelisted(address _creator) external view returns (bool);
    
      /** 
       * @notice A distinct Uniform Resource Identifier (URI) for a given asset.
       * @dev Throws if `_tokenId` is not a valid NFT. URIs are defined in RFC
       * 3986. The URI may point to a JSON file that conforms to the "ERC721
       * Metadata JSON Schema".
       */
      function tokenURI(uint256 _tokenId) external view returns (string);
    
      /**
      * @dev Gets the creator of the token
      * @param _tokenId uint256 ID of the token
      * @return address of the creator
      */
      function creatorOfToken(uint256 _tokenId) public view returns (address);
    
      /**
      * @dev Gets the total amount of tokens stored by the contract
      * @return uint256 representing the total amount of tokens
      */
      function totalSupply() public view returns (uint256);
    }
    
    /**
     * @title ERC721 token receiver interface
     * @dev Interface for any contract that wants to support safeTransfers
     * from ERC721 asset contracts.
     */
    contract IERC721Receiver {
      /**
       * @notice Handle the receipt of an NFT
       * @dev The ERC721 smart contract calls this function on the recipient
       * after a `safeTransfer`. This function MUST return the function selector,
       * otherwise the caller will revert the transaction. The selector to be
       * returned can be obtained as `this.onERC721Received.selector`. This
       * function MAY throw to revert and reject the transfer.
       * Note: the ERC721 contract address is always the message sender.
       * @param operator The address which called `safeTransferFrom` function
       * @param from The address which previously owned the token
       * @param tokenId The NFT identifier which is being transferred
       * @param data Additional data with no specified format
       * @return `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
       */
      function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes data
      )
        public
        returns(bytes4);
    }
    
    contract IERC721 is IERC165 {
    
      event Transfer(
        address indexed from,
        address indexed to,
        uint256 indexed tokenId
      );
      event Approval(
        address indexed owner,
        address indexed approved,
        uint256 indexed tokenId
      );
      event ApprovalForAll(
        address indexed owner,
        address indexed operator,
        bool approved
      );
    
      function balanceOf(address owner) public view returns (uint256 balance);
      function ownerOf(uint256 tokenId) public view returns (address owner);
    
      function approve(address to, uint256 tokenId) public;
      function getApproved(uint256 tokenId)
        public view returns (address operator);
    
      function setApprovalForAll(address operator, bool _approved) public;
      function isApprovedForAll(address owner, address operator)
        public view returns (bool);
    
      function transferFrom(address from, address to, uint256 tokenId) public;
      function safeTransferFrom(address from, address to, uint256 tokenId)
        public;
    
      function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes data
      )
        public;
    }
    
    contract IERC721Creator is IERC721 {
        /**
       * @dev Gets the creator of the token
       * @param _tokenId uint256 ID of the token
       * @return address of the creator
       */
        function tokenCreator(uint256 _tokenId) public view returns (address);
    }
    
    /**
     * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
     * @dev See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
     */
    contract IERC721Metadata is IERC721 {
      function name() external view returns (string);
      function symbol() external view returns (string);
      function tokenURI(uint256 tokenId) external view returns (string);
    }
    
    /**
     * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
     * @dev See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
     */
    contract IERC721Enumerable is IERC721 {
      function totalSupply() public view returns (uint256);
      function tokenOfOwnerByIndex(
        address owner,
        uint256 index
      )
        public
        view
        returns (uint256 tokenId);
    
      function tokenByIndex(uint256 index) public view returns (uint256);
    }
    
    /**
     * Utility library of inline functions on addresses
     */
    library Address {
    
      /**
       * Returns whether the target address is a contract
       * @dev This function will return false if invoked during the constructor of a contract,
       * as the code is not actually created until after the constructor finishes.
       * @param account address of the account to check
       * @return whether the target address is a contract
       */
      function isContract(address account) internal view returns (bool) {
        uint256 size;
        // XXX Currently there is no better way to check if there is a contract in an address
        // than to check the size of the code at that address.
        // See https://ethereum.stackexchange.com/a/14016/36603
        // for more details about how this works.
        // TODO Check this again before the Serenity release, because all addresses will be
        // contracts then.
        // solium-disable-next-line security/no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
      }
    
    }
    
    /**
     * @title ERC165
     * @author Matt Condon (@shrugs)
     * @dev Implements ERC165 using a lookup table.
     */
    contract ERC165 is IERC165 {
    
      bytes4 private constant _InterfaceId_ERC165 = 0x01ffc9a7;
      /**
       * 0x01ffc9a7 ===
       *   bytes4(keccak256('supportsInterface(bytes4)'))
       */
    
      /**
       * @dev a mapping of interface id to whether or not it's supported
       */
      mapping(bytes4 => bool) private _supportedInterfaces;
    
      /**
       * @dev A contract implementing SupportsInterfaceWithLookup
       * implement ERC165 itself
       */
      constructor()
        internal
      {
        _registerInterface(_InterfaceId_ERC165);
      }
    
      /**
       * @dev implement supportsInterface(bytes4) using a lookup table
       */
      function supportsInterface(bytes4 interfaceId)
        external
        view
        returns (bool)
      {
        return _supportedInterfaces[interfaceId];
      }
    
      /**
       * @dev internal method for registering an interface
       */
      function _registerInterface(bytes4 interfaceId)
        internal
      {
        require(interfaceId != 0xffffffff);
        _supportedInterfaces[interfaceId] = true;
      }
    }
    
    /**
     * @title ERC721 Non-Fungible Token Standard basic implementation
     * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
     */
    contract ERC721 is ERC165, IERC721 {
    
      using SafeMath for uint256;
      using Address for address;
    
      // Equals to `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`
      // which can be also obtained as `IERC721Receiver(0).onERC721Received.selector`
      bytes4 private constant _ERC721_RECEIVED = 0x150b7a02;
    
      // Mapping from token ID to owner
      mapping (uint256 => address) private _tokenOwner;
    
      // Mapping from token ID to approved address
      mapping (uint256 => address) private _tokenApprovals;
    
      // Mapping from owner to number of owned token
      mapping (address => uint256) private _ownedTokensCount;
    
      // Mapping from owner to operator approvals
      mapping (address => mapping (address => bool)) private _operatorApprovals;
    
      bytes4 private constant _InterfaceId_ERC721 = 0x80ac58cd;
      /*
       * 0x80ac58cd ===
       *   bytes4(keccak256('balanceOf(address)')) ^
       *   bytes4(keccak256('ownerOf(uint256)')) ^
       *   bytes4(keccak256('approve(address,uint256)')) ^
       *   bytes4(keccak256('getApproved(uint256)')) ^
       *   bytes4(keccak256('setApprovalForAll(address,bool)')) ^
       *   bytes4(keccak256('isApprovedForAll(address,address)')) ^
       *   bytes4(keccak256('transferFrom(address,address,uint256)')) ^
       *   bytes4(keccak256('safeTransferFrom(address,address,uint256)')) ^
       *   bytes4(keccak256('safeTransferFrom(address,address,uint256,bytes)'))
       */
    
      constructor()
        public
      {
        // register the supported interfaces to conform to ERC721 via ERC165
        _registerInterface(_InterfaceId_ERC721);
      }
    
      /**
       * @dev Gets the balance of the specified address
       * @param owner address to query the balance of
       * @return uint256 representing the amount owned by the passed address
       */
      function balanceOf(address owner) public view returns (uint256) {
        require(owner != address(0));
        return _ownedTokensCount[owner];
      }
    
      /**
       * @dev Gets the owner of the specified token ID
       * @param tokenId uint256 ID of the token to query the owner of
       * @return owner address currently marked as the owner of the given token ID
       */
      function ownerOf(uint256 tokenId) public view returns (address) {
        address owner = _tokenOwner[tokenId];
        require(owner != address(0));
        return owner;
      }
    
      /**
       * @dev Approves another address to transfer the given token ID
       * The zero address indicates there is no approved address.
       * There can only be one approved address per token at a given time.
       * Can only be called by the token owner or an approved operator.
       * @param to address to be approved for the given token ID
       * @param tokenId uint256 ID of the token to be approved
       */
      function approve(address to, uint256 tokenId) public {
        address owner = ownerOf(tokenId);
        require(to != owner);
        require(msg.sender == owner || isApprovedForAll(owner, msg.sender));
    
        _tokenApprovals[tokenId] = to;
        emit Approval(owner, to, tokenId);
      }
    
      /**
       * @dev Gets the approved address for a token ID, or zero if no address set
       * Reverts if the token ID does not exist.
       * @param tokenId uint256 ID of the token to query the approval of
       * @return address currently approved for the given token ID
       */
      function getApproved(uint256 tokenId) public view returns (address) {
        require(_exists(tokenId));
        return _tokenApprovals[tokenId];
      }
    
      /**
       * @dev Sets or unsets the approval of a given operator
       * An operator is allowed to transfer all tokens of the sender on their behalf
       * @param to operator address to set the approval
       * @param approved representing the status of the approval to be set
       */
      function setApprovalForAll(address to, bool approved) public {
        require(to != msg.sender);
        _operatorApprovals[msg.sender][to] = approved;
        emit ApprovalForAll(msg.sender, to, approved);
      }
    
      /**
       * @dev Tells whether an operator is approved by a given owner
       * @param owner owner address which you want to query the approval of
       * @param operator operator address which you want to query the approval of
       * @return bool whether the given operator is approved by the given owner
       */
      function isApprovedForAll(
        address owner,
        address operator
      )
        public
        view
        returns (bool)
      {
        return _operatorApprovals[owner][operator];
      }
    
      /**
       * @dev Transfers the ownership of a given token ID to another address
       * Usage of this method is discouraged, use `safeTransferFrom` whenever possible
       * Requires the msg sender to be the owner, approved, or operator
       * @param from current owner of the token
       * @param to address to receive the ownership of the given token ID
       * @param tokenId uint256 ID of the token to be transferred
      */
      function transferFrom(
        address from,
        address to,
        uint256 tokenId
      )
        public
      {
        require(_isApprovedOrOwner(msg.sender, tokenId));
        require(to != address(0));
    
        _clearApproval(from, tokenId);
        _removeTokenFrom(from, tokenId);
        _addTokenTo(to, tokenId);
    
        emit Transfer(from, to, tokenId);
      }
    
      /**
       * @dev Safely transfers the ownership of a given token ID to another address
       * If the target address is a contract, it must implement `onERC721Received`,
       * which is called upon a safe transfer, and return the magic value
       * `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
       * the transfer is reverted.
       *
       * Requires the msg sender to be the owner, approved, or operator
       * @param from current owner of the token
       * @param to address to receive the ownership of the given token ID
       * @param tokenId uint256 ID of the token to be transferred
      */
      function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
      )
        public
      {
        // solium-disable-next-line arg-overflow
        safeTransferFrom(from, to, tokenId, "");
      }
    
      /**
       * @dev Safely transfers the ownership of a given token ID to another address
       * If the target address is a contract, it must implement `onERC721Received`,
       * which is called upon a safe transfer, and return the magic value
       * `bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"))`; otherwise,
       * the transfer is reverted.
       * Requires the msg sender to be the owner, approved, or operator
       * @param from current owner of the token
       * @param to address to receive the ownership of the given token ID
       * @param tokenId uint256 ID of the token to be transferred
       * @param _data bytes data to send along with a safe transfer check
       */
      function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes _data
      )
        public
      {
        transferFrom(from, to, tokenId);
        // solium-disable-next-line arg-overflow
        require(_checkOnERC721Received(from, to, tokenId, _data));
      }
    
      /**
       * @dev Returns whether the specified token exists
       * @param tokenId uint256 ID of the token to query the existence of
       * @return whether the token exists
       */
      function _exists(uint256 tokenId) internal view returns (bool) {
        address owner = _tokenOwner[tokenId];
        return owner != address(0);
      }
    
      /**
       * @dev Returns whether the given spender can transfer a given token ID
       * @param spender address of the spender to query
       * @param tokenId uint256 ID of the token to be transferred
       * @return bool whether the msg.sender is approved for the given token ID,
       *  is an operator of the owner, or is the owner of the token
       */
      function _isApprovedOrOwner(
        address spender,
        uint256 tokenId
      )
        internal
        view
        returns (bool)
      {
        address owner = ownerOf(tokenId);
        // Disable solium check because of
        // https://github.com/duaraghav8/Solium/issues/175
        // solium-disable-next-line operator-whitespace
        return (
          spender == owner ||
          getApproved(tokenId) == spender ||
          isApprovedForAll(owner, spender)
        );
      }
    
      /**
       * @dev Internal function to mint a new token
       * Reverts if the given token ID already exists
       * @param to The address that will own the minted token
       * @param tokenId uint256 ID of the token to be minted by the msg.sender
       */
      function _mint(address to, uint256 tokenId) internal {
        require(to != address(0));
        _addTokenTo(to, tokenId);
        emit Transfer(address(0), to, tokenId);
      }
    
      /**
       * @dev Internal function to burn a specific token
       * Reverts if the token does not exist
       * @param tokenId uint256 ID of the token being burned by the msg.sender
       */
      function _burn(address owner, uint256 tokenId) internal {
        _clearApproval(owner, tokenId);
        _removeTokenFrom(owner, tokenId);
        emit Transfer(owner, address(0), tokenId);
      }
    
      /**
       * @dev Internal function to add a token ID to the list of a given address
       * Note that this function is left internal to make ERC721Enumerable possible, but is not
       * intended to be called by custom derived contracts: in particular, it emits no Transfer event.
       * @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 _addTokenTo(address to, uint256 tokenId) internal {
        require(_tokenOwner[tokenId] == address(0));
        _tokenOwner[tokenId] = to;
        _ownedTokensCount[to] = _ownedTokensCount[to].add(1);
      }
    
      /**
       * @dev Internal function to remove a token ID from the list of a given address
       * Note that this function is left internal to make ERC721Enumerable possible, but is not
       * intended to be called by custom derived contracts: in particular, it emits no Transfer event,
       * and doesn't clear approvals.
       * @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 _removeTokenFrom(address from, uint256 tokenId) internal {
        require(ownerOf(tokenId) == from);
        _ownedTokensCount[from] = _ownedTokensCount[from].sub(1);
        _tokenOwner[tokenId] = address(0);
      }
    
      /**
       * @dev Internal function to invoke `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 whether the call correctly returned the expected magic value
       */
      function _checkOnERC721Received(
        address from,
        address to,
        uint256 tokenId,
        bytes _data
      )
        internal
        returns (bool)
      {
        if (!to.isContract()) {
          return true;
        }
        bytes4 retval = IERC721Receiver(to).onERC721Received(
          msg.sender, from, tokenId, _data);
        return (retval == _ERC721_RECEIVED);
      }
    
      /**
       * @dev Private function to clear current approval of a given token ID
       * Reverts if the given address is not indeed the owner of the token
       * @param owner owner of the token
       * @param tokenId uint256 ID of the token to be transferred
       */
      function _clearApproval(address owner, uint256 tokenId) private {
        require(ownerOf(tokenId) == owner);
        if (_tokenApprovals[tokenId] != address(0)) {
          _tokenApprovals[tokenId] = address(0);
        }
      }
    }
    
    contract ERC721Enumerable is ERC165, ERC721, IERC721Enumerable {
      // Mapping from owner to list of owned token IDs
      mapping(address => 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;
    
      bytes4 private constant _InterfaceId_ERC721Enumerable = 0x780e9d63;
      /**
       * 0x780e9d63 ===
       *   bytes4(keccak256('totalSupply()')) ^
       *   bytes4(keccak256('tokenOfOwnerByIndex(address,uint256)')) ^
       *   bytes4(keccak256('tokenByIndex(uint256)'))
       */
    
      /**
       * @dev Constructor function
       */
      constructor() public {
        // register the supported interface to conform to ERC721 via ERC165
        _registerInterface(_InterfaceId_ERC721Enumerable);
      }
    
      /**
       * @dev Gets the token ID at a given index of the tokens list of the requested owner
       * @param owner address owning the tokens list to be accessed
       * @param index uint256 representing the index to be accessed of the requested tokens list
       * @return uint256 token ID at the given index of the tokens list owned by the requested address
       */
      function tokenOfOwnerByIndex(
        address owner,
        uint256 index
      )
        public
        view
        returns (uint256)
      {
        require(index < balanceOf(owner));
        return _ownedTokens[owner][index];
      }
    
      /**
       * @dev Gets the total amount of tokens stored by the contract
       * @return uint256 representing the total amount of tokens
       */
      function totalSupply() public view returns (uint256) {
        return _allTokens.length;
      }
    
      /**
       * @dev Gets the token ID at a given index of all the tokens in this contract
       * Reverts if the index is greater or equal to the total number of tokens
       * @param index uint256 representing the index to be accessed of the tokens list
       * @return uint256 token ID at the given index of the tokens list
       */
      function tokenByIndex(uint256 index) public view returns (uint256) {
        require(index < totalSupply());
        return _allTokens[index];
      }
    
      /**
       * @dev Internal function to add a token ID to the list of a given address
       * This function is internal due to language limitations, see the note in ERC721.sol.
       * It is not intended to be called by custom derived contracts: in particular, it emits no Transfer event.
       * @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 _addTokenTo(address to, uint256 tokenId) internal {
        super._addTokenTo(to, tokenId);
        uint256 length = _ownedTokens[to].length;
        _ownedTokens[to].push(tokenId);
        _ownedTokensIndex[tokenId] = length;
      }
    
      /**
       * @dev Internal function to remove a token ID from the list of a given address
       * This function is internal due to language limitations, see the note in ERC721.sol.
       * It is not intended to be called by custom derived contracts: in particular, it emits no Transfer event,
       * and doesn't clear approvals.
       * @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 _removeTokenFrom(address from, uint256 tokenId) internal {
        super._removeTokenFrom(from, tokenId);
    
        // To prevent a gap in the array, we store the last token in the index of the token to delete, and
        // then delete the last slot.
        uint256 tokenIndex = _ownedTokensIndex[tokenId];
        uint256 lastTokenIndex = _ownedTokens[from].length.sub(1);
        uint256 lastToken = _ownedTokens[from][lastTokenIndex];
    
        _ownedTokens[from][tokenIndex] = lastToken;
        // This also deletes the contents at the last position of the array
        _ownedTokens[from].length--;
    
        // Note that this will handle single-element arrays. In that case, both tokenIndex and lastTokenIndex are going to
        // be zero. Then we can make sure that we will remove tokenId from the ownedTokens list since we are first swapping
        // the lastToken to the first position, and then dropping the element placed in the last position of the list
    
        _ownedTokensIndex[tokenId] = 0;
        _ownedTokensIndex[lastToken] = tokenIndex;
      }
    
      /**
       * @dev Internal function to mint a new token
       * Reverts if the given token ID already exists
       * @param to address the beneficiary that will own the minted token
       * @param tokenId uint256 ID of the token to be minted by the msg.sender
       */
      function _mint(address to, uint256 tokenId) internal {
        super._mint(to, tokenId);
    
        _allTokensIndex[tokenId] = _allTokens.length;
        _allTokens.push(tokenId);
      }
    
      /**
       * @dev Internal function to burn a specific token
       * Reverts if the token does not exist
       * @param owner owner of the token to burn
       * @param tokenId uint256 ID of the token being burned by the msg.sender
       */
      function _burn(address owner, uint256 tokenId) internal {
        super._burn(owner, tokenId);
    
        // Reorg all tokens array
        uint256 tokenIndex = _allTokensIndex[tokenId];
        uint256 lastTokenIndex = _allTokens.length.sub(1);
        uint256 lastToken = _allTokens[lastTokenIndex];
    
        _allTokens[tokenIndex] = lastToken;
        _allTokens[lastTokenIndex] = 0;
    
        _allTokens.length--;
        _allTokensIndex[tokenId] = 0;
        _allTokensIndex[lastToken] = tokenIndex;
      }
    }
    
    contract ERC721Metadata is ERC165, ERC721, IERC721Metadata {
      // Token name
      string private _name;
    
      // Token symbol
      string private _symbol;
    
      // Optional mapping for token URIs
      mapping(uint256 => string) private _tokenURIs;
    
      bytes4 private constant InterfaceId_ERC721Metadata = 0x5b5e139f;
      /**
       * 0x5b5e139f ===
       *   bytes4(keccak256('name()')) ^
       *   bytes4(keccak256('symbol()')) ^
       *   bytes4(keccak256('tokenURI(uint256)'))
       */
    
      /**
       * @dev Constructor function
       */
      constructor(string name, string symbol) public {
        _name = name;
        _symbol = symbol;
    
        // register the supported interfaces to conform to ERC721 via ERC165
        _registerInterface(InterfaceId_ERC721Metadata);
      }
    
      /**
       * @dev Gets the token name
       * @return string representing the token name
       */
      function name() external view returns (string) {
        return _name;
      }
    
      /**
       * @dev Gets the token symbol
       * @return string representing the token symbol
       */
      function symbol() external view returns (string) {
        return _symbol;
      }
    
      /**
       * @dev Returns an URI for a given token ID
       * Throws if the token ID does not exist. May return an empty string.
       * @param tokenId uint256 ID of the token to query
       */
      function tokenURI(uint256 tokenId) external view returns (string) {
        require(_exists(tokenId));
        return _tokenURIs[tokenId];
      }
    
      /**
       * @dev Internal function to set the token URI for a given token
       * Reverts if the token ID does not exist
       * @param tokenId uint256 ID of the token to set its URI
       * @param uri string URI to assign
       */
      function _setTokenURI(uint256 tokenId, string uri) internal {
        require(_exists(tokenId));
        _tokenURIs[tokenId] = uri;
      }
    
      /**
       * @dev Internal function to burn a specific token
       * Reverts if the token does not exist
       * @param owner owner of the token to burn
       * @param tokenId uint256 ID of the token being burned by the msg.sender
       */
      function _burn(address owner, uint256 tokenId) internal {
        super._burn(owner, tokenId);
    
        // Clear metadata (if any)
        if (bytes(_tokenURIs[tokenId]).length != 0) {
          delete _tokenURIs[tokenId];
        }
      }
    }
    
    /**
     * @title Ownable
     * @dev The Ownable contract has an owner address, and provides basic authorization control
     * functions, this simplifies the implementation of "user permissions".
     */
    contract Ownable {
      address private _owner;
    
      event OwnershipTransferred(
        address indexed previousOwner,
        address indexed newOwner
      );
    
      /**
       * @dev The Ownable constructor sets the original `owner` of the contract to the sender
       * account.
       */
      constructor() internal {
        _owner = msg.sender;
        emit OwnershipTransferred(address(0), _owner);
      }
    
      /**
       * @return the address of the owner.
       */
      function owner() public view returns(address) {
        return _owner;
      }
    
      /**
       * @dev Throws if called by any account other than the owner.
       */
      modifier onlyOwner() {
        require(isOwner());
        _;
      }
    
      /**
       * @return true if `msg.sender` is the owner of the contract.
       */
      function isOwner() public view returns(bool) {
        return msg.sender == _owner;
      }
    
      /**
       * @dev Allows the current owner to relinquish control of the contract.
       * @notice Renouncing to ownership will leave the contract without an owner.
       * It will not be possible to call the functions with the `onlyOwner`
       * modifier anymore.
       */
      function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
      }
    
      /**
       * @dev Allows the current owner to transfer control of the contract to a newOwner.
       * @param newOwner The address to transfer ownership to.
       */
      function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
      }
    
      /**
       * @dev Transfers control of the contract to a newOwner.
       * @param newOwner The address to transfer ownership to.
       */
      function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0));
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
      }
    }
    
    contract Whitelist is Ownable {
        // Mapping of address to boolean indicating whether the address is whitelisted
        mapping(address => bool) private whitelistMap;
    
        // flag controlling whether whitelist is enabled.
        bool private whitelistEnabled = true;
    
        event AddToWhitelist(address indexed _newAddress);
        event RemoveFromWhitelist(address indexed _removedAddress);
    
        /**
       * @dev Enable or disable the whitelist
       * @param _enabled bool of whether to enable the whitelist.
       */
        function enableWhitelist(bool _enabled) public onlyOwner {
            whitelistEnabled = _enabled;
        }
    
        /**
       * @dev Adds the provided address to the whitelist
       * @param _newAddress address to be added to the whitelist
       */
        function addToWhitelist(address _newAddress) public onlyOwner {
            _whitelist(_newAddress);
            emit AddToWhitelist(_newAddress);
        }
    
        /**
       * @dev Removes the provided address to the whitelist
       * @param _removedAddress address to be removed from the whitelist
       */
        function removeFromWhitelist(address _removedAddress) public onlyOwner {
            _unWhitelist(_removedAddress);
            emit RemoveFromWhitelist(_removedAddress);
        }
    
        /**
       * @dev Returns whether the address is whitelisted
       * @param _address address to check
       * @return bool
       */
        function isWhitelisted(address _address) public view returns (bool) {
            if (whitelistEnabled) {
                return whitelistMap[_address];
            } else {
                return true;
            }
        }
    
        /**
       * @dev Internal function for removing an address from the whitelist
       * @param _removedAddress address to unwhitelisted
       */
        function _unWhitelist(address _removedAddress) internal {
            whitelistMap[_removedAddress] = false;
        }
    
        /**
       * @dev Internal function for adding the provided address to the whitelist
       * @param _newAddress address to be added to the whitelist
       */
        function _whitelist(address _newAddress) internal {
            whitelistMap[_newAddress] = true;
        }
    }
    
    /**
     * @title Full ERC721 Token
     * This implementation includes all the required and some optional functionality of the ERC721 standard
     * Moreover, it includes approve all functionality using operator terminology
     * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
     */
    contract ERC721Full is ERC721, ERC721Enumerable, ERC721Metadata {
      constructor(string name, string symbol) ERC721Metadata(name, symbol)
        public
      {
      }
    }
    
    
    contract SuperRareV2 is ERC721Full, IERC721Creator, Ownable, Whitelist {
        using SafeMath for uint256;
    
        // Mapping from token ID to the creator's address.
        mapping(uint256 => address) private tokenCreators;
    
        // Counter for creating token IDs
        uint256 private idCounter;
    
        // Old SuperRare contract to look up token details.
        ISuperRare private oldSuperRare;
    
        // Event indicating metadata was updated.
        event TokenURIUpdated(uint256 indexed _tokenId, string  _uri);
    
        constructor(
          string _name,
          string _symbol,
          address _oldSuperRare
        )
        ERC721Full(_name, _symbol)
        {
          // Get reference to old SR contract.
          oldSuperRare = ISuperRare(_oldSuperRare);
    
          uint256 oldSupply = oldSuperRare.totalSupply();
          // Set id counter to be continuous with SuperRare.
          idCounter = oldSupply + 1;
        }
    
        /**
         * @dev Whitelists a bunch of addresses.
         * @param _whitelistees address[] of addresses to whitelist.
         */
        function initWhitelist(address[] _whitelistees) public onlyOwner {
          // Add all whitelistees.
          for (uint256 i = 0; i < _whitelistees.length; i++) {
            address creator = _whitelistees[i];
            if (!isWhitelisted(creator)) {
              _whitelist(creator);
            }
          }
        }
    
        /**
         * @dev Checks that the token is owned by the sender.
         * @param _tokenId uint256 ID of the token.
         */
        modifier onlyTokenOwner(uint256 _tokenId) {
          address owner = ownerOf(_tokenId);
          require(owner == msg.sender, "must be the owner of the token");
          _;
        }
    
        /**
         * @dev Checks that the token was created by the sender.
         * @param _tokenId uint256 ID of the token.
         */
        modifier onlyTokenCreator(uint256 _tokenId) {
          address creator = tokenCreator(_tokenId);
          require(creator == msg.sender, "must be the creator of the token");
          _;
        }
    
        /**
         * @dev Adds a new unique token to the supply.
         * @param _uri string metadata uri associated with the token.
         */
        function addNewToken(string _uri) public {
          require(isWhitelisted(msg.sender), "must be whitelisted to create tokens");
          _createToken(_uri, msg.sender);
        }
    
        /**
         * @dev Deletes the token with the provided ID.
         * @param _tokenId uint256 ID of the token.
         */
        function deleteToken(uint256 _tokenId) public onlyTokenOwner(_tokenId) {
          _burn(msg.sender, _tokenId);
        }
    
        /**
         * @dev Updates the token metadata if the owner is also the
         *      creator.
         * @param _tokenId uint256 ID of the token.
         * @param _uri string metadata URI.
         */
        function updateTokenMetadata(uint256 _tokenId, string _uri)
          public
          onlyTokenOwner(_tokenId)
          onlyTokenCreator(_tokenId)
        {
          _setTokenURI(_tokenId, _uri);
          emit TokenURIUpdated(_tokenId, _uri);
        }
    
        /**
        * @dev Gets the creator of the token.
        * @param _tokenId uint256 ID of the token.
        * @return address of the creator.
        */
        function tokenCreator(uint256 _tokenId) public view returns (address) {
            return tokenCreators[_tokenId];
        }
    
        /**
         * @dev Internal function for setting the token's creator.
         * @param _tokenId uint256 id of the token.
         * @param _creator address of the creator of the token.
         */
        function _setTokenCreator(uint256 _tokenId, address _creator) internal {
          tokenCreators[_tokenId] = _creator;
        }
    
        /**
         * @dev Internal function creating a new token.
         * @param _uri string metadata uri associated with the token
         * @param _creator address of the creator of the token.
         */
        function _createToken(string _uri, address _creator) internal returns (uint256) {
          uint256 newId = idCounter;
          idCounter++;
          _mint(_creator, newId);
          _setTokenURI(newId, _uri);
          _setTokenCreator(newId, _creator);
          return newId;
        }
    }