// File: contracts/drops/GiftContractV2.sol



//SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.4;
import "@openzeppelin/contracts/access/AccessControl.sol";
//import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "erc721a/contracts/IERC721A.sol";
import "../interfaces/IMembershipNFT.sol";
import "../interfaces/IGiftContract.sol";

contract GiftContractV2 is IGiftContract, AccessControl {
    uint256 public confirmsRequired;
    uint8 private constant ID_MOG = 0;
    uint8 private constant ID_INV = 1;

    bytes32 public constant MINTER_ROLE = keccak256("MINTER_ROLE");
    bytes32 public constant OWNER_ROLE = keccak256("OWNER_ROLE");

    mapping(uint8 => uint16) public giftLimit;
    mapping(uint8 => uint16) public giftReserves;
    mapping(uint8 => uint256) internal _giftSupply;
    mapping(address => mapping(uint8 => uint256)) public giftList;

    bool private _initialized;

    address public nftToken;
    address public tokenPool;

    struct Txn {
        address to;
        uint256[] amounts;
        bytes data;
        bool executed;
        uint256 confirms;
    }

    // mapping from tx index => owner => bool
    mapping(uint256 => mapping(address => bool)) public isConfirmed;

    Txn[] public txns;
    modifier onlyOwner() {
        address account = msg.sender;
        require(
            hasRole(DEFAULT_ADMIN_ROLE, account) ||
                hasRole(MINTER_ROLE, account) ||
                hasRole(OWNER_ROLE, account),
            "Not admin"
        );
        _;
    }

    modifier txExists(uint256 _txIndex) {
        require(_txIndex < txns.length, "tx does not exist");
        _;
    }

    modifier notExecuted(uint256 _txIndex) {
        require(!txns[_txIndex].executed, "tx already executed");
        _;
    }

    modifier notConfirmed(uint256 _txIndex) {
        require(!isConfirmed[_txIndex][msg.sender], "tx already confirmed");
        _;
    }
    modifier initializer() {
        require(!_initialized, "GIFT_ALREADY_INITIALIZED");
        _initialized = true;
        _;
    }

    constructor() {
        _grantRole(DEFAULT_ADMIN_ROLE, msg.sender);
        _grantRole(MINTER_ROLE, msg.sender);
        _grantRole(OWNER_ROLE, msg.sender);
    }

    function initialize(address token, address pool)
        external
        initializer
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        require(
            token != address(0) && pool != address(0),
            "GIFT_INIT_ZERO_ADDRESS"
        );
        nftToken = token;
        tokenPool = pool;
        setGiftLimit(ID_MOG, 1);
        setGiftLimit(ID_INV, 1);
        giftReserves[ID_MOG] = 4;
        giftReserves[ID_INV] = 5;
        confirmsRequired = 2;
    }

    function setGiftLimit(uint8 tierIndex, uint8 limit) public onlyOwner {
        unchecked {
            giftLimit[tierIndex] = limit;
        }
        emit UpdateGiftLimit(msg.sender, tierIndex, limit);
    }

    function setGiftReserve(uint16[] memory reserves) public onlyOwner {
        unchecked {
            for (uint8 i = 0; i < reserves.length; i++) {
                giftReserves[i] = reserves[i];
            }
        }
        emit UpdateGiftReserves(msg.sender, reserves);
    }

    function setNumConfirms(uint256 number) public onlyOwner {
        unchecked {
            confirmsRequired = number;
        }
    }

    function getTransactionCount() public view returns (uint256) {
        return txns.length;
    }

    function getTransaction(uint256 _txIndex)
        public
        view
        returns (
            address to,
            uint256[] memory amounts,
            bytes memory data,
            bool executed,
            uint256 numConfirmations
        )
    {
        Txn storage transaction = txns[_txIndex];

        return (
            transaction.to,
            transaction.amounts,
            transaction.data,
            transaction.executed,
            transaction.confirms
        );
    }

    /**
    Muti Signature Txn Functions
 */
    function _submit(
        address _to,
        uint8 _tierIndex,
        uint256 _amount,
        bytes memory _data
    ) internal returns (uint256) {
        uint256 txIndex = txns.length;

        uint256 giftTierSupply = _giftSupply[_tierIndex];
        uint256 giftReserve = giftReserves[_tierIndex];

        require(_amount > 0, "GIFT_INVAID_AMOUNT");
        require(giftTierSupply + _amount <= giftReserve, "GIFT_OUT_OF_STOCK");
        require(
            giftList[_to][_tierIndex] + _amount <= giftLimit[_tierIndex],
            "GIFT_EXCEED_ALLOC"
        );
        uint256[] memory _amounts = new uint256[](2);
        _amounts[_tierIndex] = _amount;

        txns.push(
            Txn({
                to: _to,
                amounts: _amounts,
                data: _data,
                executed: false,
                confirms: 0
            })
        );
        return txIndex;
    }

    function _confirm(uint256 _txIndex) internal {
        Txn storage transaction = txns[_txIndex];
        transaction.confirms += 1;
        isConfirmed[_txIndex][msg.sender] = true;
    }

    function _execute(uint256 _txIndex) internal {
        Txn storage transaction = txns[_txIndex];
        uint256[] memory amounts = transaction.amounts;
        IMembershipNFT nftContract = IMembershipNFT(nftToken);

        require(transaction.confirms >= confirmsRequired, "cannot execute tx");

        transaction.executed = true;
        for (uint8 i = 0; i < amounts.length; i++) {
            uint256 giftTierSupply = _giftSupply[i];
            uint256 startId = nftContract.tierStartId(i);
            for (uint256 j = 0; j < amounts[i]; j++) {
                (bool success, ) = address(nftToken).call(
                    abi.encodeWithSignature(
                        "safeTransferFrom(address,address,uint256)",
                        tokenPool,
                        transaction.to,
                        startId + giftTierSupply + j
                    )
                );
                require(success, "tx failed");
            }
            _giftSupply[i] += amounts[i];
            giftList[transaction.to][i] += amounts[i];
        }
    }

    function _revoke(uint256 _txIndex) internal {
        Txn storage transaction = txns[_txIndex];

        require(isConfirmed[_txIndex][msg.sender], "tx not confirmed");

        transaction.confirms -= 1;
        isConfirmed[_txIndex][msg.sender] = false;
    }

    function submit(
        address _to,
        uint8 _tierIndex,
        uint256 _amount,
        bytes memory _data
    ) public onlyOwner {
        uint256 txIndex = txns.length;
        _submit(_to, _tierIndex, _amount, _data);
        emit Submit(msg.sender, txIndex, _to, _tierIndex, _amount, _data);
    }

    function confirm(uint256 _txIndex)
        public
        onlyOwner
        txExists(_txIndex)
        notExecuted(_txIndex)
        notConfirmed(_txIndex)
    {
        Txn storage transaction = txns[_txIndex];
        transaction.confirms += 1;
        isConfirmed[_txIndex][msg.sender] = true;

        emit Confirm(msg.sender, _txIndex);
    }

    function execute(uint256 _txIndex)
        public
        onlyOwner
        txExists(_txIndex)
        notExecuted(_txIndex)
    {
        _execute(_txIndex);
        emit Execute(msg.sender, _txIndex);
    }

    function revoke(uint256 _txIndex)
        public
        onlyOwner
        txExists(_txIndex)
        notExecuted(_txIndex)
    {
        _revoke(_txIndex);
        emit Revoke(msg.sender, _txIndex);
    }

    function submitAndConfirm(
        address _to,
        uint8 _tierIndex,
        uint256 _amount,
        bytes memory _data
    ) public onlyOwner {
        uint txIndex = _submit(_to, _tierIndex, _amount, _data);
        _confirm(txIndex);
        emit SubmitAndConfirm(msg.sender, txIndex, _to, _tierIndex, _amount, _data);
    }
        function confirmAndExecute(uint256 _txIndex)
        public
        onlyOwner
        txExists(_txIndex)
        notConfirmed(_txIndex)
        notExecuted(_txIndex)
    {
        _confirm(_txIndex);
        _execute(_txIndex);
        emit ConfirmAndExecute(msg.sender, _txIndex);
    }
    //--------------------------------------------------------------
    function totalSupply(uint8 tierIndex)
        public
        view
        override
        returns (uint256)
    {
        return _giftSupply[tierIndex];
    }

    function getNftToken() public view override returns (address) {
        require(nftToken != address(0), "TOKEN_ZERO_ADDRESS");
        return nftToken;
    }

    function getTokenPool() public view override returns (address) {
        require(tokenPool != address(0), "ACCOUNT_ZERO_ADDRESS");
        return tokenPool;
    }

    function balanceOf(address owner, uint8 tierIndex)
        public
        view
        override
        returns (uint256)
    {
        require(owner != address(0), "OWNER_ZERO_ADDRESS");
        return giftList[owner][tierIndex];
    }
}

// File: @openzeppelin/contracts/access/AccessControl.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (access/AccessControl.sol)

pragma solidity ^0.8.0;

import "./IAccessControl.sol";
import "../utils/Context.sol";
import "../utils/Strings.sol";
import "../utils/introspection/ERC165.sol";

/**
 * @dev Contract module that allows children to implement role-based access
 * control mechanisms. This is a lightweight version that doesn't allow enumerating role
 * members except through off-chain means by accessing the contract event logs. Some
 * applications may benefit from on-chain enumerability, for those cases see
 * {AccessControlEnumerable}.
 *
 * 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, IAccessControl, ERC165 {
    struct RoleData {
        mapping(address => bool) members;
        bytes32 adminRole;
    }

    mapping(bytes32 => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /**
     * @dev Modifier that checks that an account has a specific role. Reverts
     * with a standardized message including the required role.
     *
     * The format of the revert reason is given by the following regular expression:
     *
     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
     *
     * _Available since v4.1._
     */
    modifier onlyRole(bytes32 role) {
        _checkRole(role);
        _;
    }

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

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
        return _roles[role].members[account];
    }

    /**
     * @dev Revert with a standard message if `_msgSender()` is missing `role`.
     * Overriding this function changes the behavior of the {onlyRole} modifier.
     *
     * Format of the revert message is described in {_checkRole}.
     *
     * _Available since v4.6._
     */
    function _checkRole(bytes32 role) internal view virtual {
        _checkRole(role, _msgSender());
    }

    /**
     * @dev Revert with a standard message if `account` is missing `role`.
     *
     * The format of the revert reason is given by the following regular expression:
     *
     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
     */
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!hasRole(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "AccessControl: account ",
                        Strings.toHexString(uint160(account), 20),
                        " is missing role ",
                        Strings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }

    /**
     * @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 virtual override 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 override onlyRole(getRoleAdmin(role)) {
        _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 override onlyRole(getRoleAdmin(role)) {
        _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 revoked `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) public virtual override {
        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}.
     * ====
     *
     * NOTE: This function is deprecated in favor of {_grantRole}.
     */
    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 {
        bytes32 previousAdminRole = getRoleAdmin(role);
        _roles[role].adminRole = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * Internal function without access restriction.
     */
    function _grantRole(bytes32 role, address account) internal virtual {
        if (!hasRole(role, account)) {
            _roles[role].members[account] = true;
            emit RoleGranted(role, account, _msgSender());
        }
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * Internal function without access restriction.
     */
    function _revokeRole(bytes32 role, address account) internal virtual {
        if (hasRole(role, account)) {
            _roles[role].members[account] = false;
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

// File: erc721a/contracts/IERC721A.sol



// SPDX-License-Identifier: MIT
// ERC721A Contracts v3.3.0
// Creator: Chiru Labs

pragma solidity ^0.8.4;

import '@openzeppelin/contracts/token/ERC721/IERC721.sol';
import '@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol';

/**
 * @dev Interface of an ERC721A compliant contract.
 */
interface IERC721A is IERC721, IERC721Metadata {
    /**
     * The caller must own the token or be an approved operator.
     */
    error ApprovalCallerNotOwnerNorApproved();

    /**
     * The token does not exist.
     */
    error ApprovalQueryForNonexistentToken();

    /**
     * The caller cannot approve to their own address.
     */
    error ApproveToCaller();

    /**
     * The caller cannot approve to the current owner.
     */
    error ApprovalToCurrentOwner();

    /**
     * Cannot query the balance for the zero address.
     */
    error BalanceQueryForZeroAddress();

    /**
     * Cannot mint to the zero address.
     */
    error MintToZeroAddress();

    /**
     * The quantity of tokens minted must be more than zero.
     */
    error MintZeroQuantity();

    /**
     * The token does not exist.
     */
    error OwnerQueryForNonexistentToken();

    /**
     * The caller must own the token or be an approved operator.
     */
    error TransferCallerNotOwnerNorApproved();

    /**
     * The token must be owned by `from`.
     */
    error TransferFromIncorrectOwner();

    /**
     * Cannot safely transfer to a contract that does not implement the ERC721Receiver interface.
     */
    error TransferToNonERC721ReceiverImplementer();

    /**
     * Cannot transfer to the zero address.
     */
    error TransferToZeroAddress();

    /**
     * The token does not exist.
     */
    error URIQueryForNonexistentToken();

    // Compiler will pack this into a single 256bit word.
    struct TokenOwnership {
        // The address of the owner.
        address addr;
        // Keeps track of the start time of ownership with minimal overhead for tokenomics.
        uint64 startTimestamp;
        // Whether the token has been burned.
        bool burned;
    }

    // Compiler will pack this into a single 256bit word.
    struct AddressData {
        // Realistically, 2**64-1 is more than enough.
        uint64 balance;
        // Keeps track of mint count with minimal overhead for tokenomics.
        uint64 numberMinted;
        // Keeps track of burn count with minimal overhead for tokenomics.
        uint64 numberBurned;
        // For miscellaneous variable(s) pertaining to the address
        // (e.g. number of whitelist mint slots used).
        // If there are multiple variables, please pack them into a uint64.
        uint64 aux;
    }

    /**
     * @dev Returns the total amount of tokens stored by the contract.
     * 
     * Burned tokens are calculated here, use `_totalMinted()` if you want to count just minted tokens.
     */
    function totalSupply() external view returns (uint256);
}

// File: contracts/interfaces/IMembershipNFT.sol



//SPDX-License-Identifier: Unlicense
// Creator: Dai
pragma solidity ^0.8.4;

interface IMembershipNFT {
    event Mint(
        address indexed operator,
        address indexed to,
        uint256 quantity,
        uint256 tierIndex
    );
    event Burn(address indexed operator, uint256 tokenID);
    event UpdateMetadataImage(string[]);
    event UpdateMetadataExternalUrl(string[]);
    event UpdateMetadataAnimationUrl(string[]);
    event SetupPool(address indexed operator, address pool);
    event Locked(address indexed operator, bool locked);
    event MintToPool(address indexed operator);

    function tierSupply(uint8) external view returns (uint256);

    function tierName(uint8) external view returns (string memory);

    function tierCount(uint8) external view returns (uint256);

    function tierStartId(uint8) external view returns (uint256);

    function tierEndId(uint8) external view returns (uint256);

    function numberTiers() external view returns (uint256);
}

// File: contracts/interfaces/IGiftContract.sol



//SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.4;

interface IGiftContract {
    event Gift(address indexed to, uint8 tierIndex, uint256 quantity);
    event UpdateGiftLimit(
        address indexed operator,
        uint8 tierIndex,
        uint256 limit
    );
    event UpdateGiftReserves(address operator, uint16[] reserves);

    event GiftToAll(address[] receivers, uint256[] tokenQuantities);
    event GiftEx(address receiver, uint256[] tokenQuantities);

    event Submit(
        address indexed owner,
        uint256 indexed txIndex,
        address indexed to,
        uint8 tierIndex,
        uint256 amount,
        bytes data
    );
    event SubmitAndConfirm(
        address indexed owner,
        uint256 indexed txIndex,
        address indexed to,
        uint8 tierIndex,
        uint256 amount,
        bytes data
    );
    event Confirm(address indexed owner, uint256 indexed txIndex);
    event ConfirmAndExecute(address indexed owner, uint256 indexed txIndex);

    event Revoke(address indexed owner, uint256 indexed txIndex);
    event Execute(address indexed owner, uint256 indexed txIndex);

    function totalSupply(uint8 tierIndex) external view returns (uint256);

    function getNftToken() external view returns (address);

    function getTokenPool() external view returns (address);

    function balanceOf(address user, uint8 tierIndex)
        external
        view
        returns (uint256);
}

// File: @openzeppelin/contracts/access/IAccessControl.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)

pragma solidity ^0.8.0;

/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IAccessControl {
    /**
     * @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 {AccessControl-_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) external view returns (bool);

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**
     * @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) external;

    /**
     * @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) external;

    /**
     * @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) external;
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

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

// File: @openzeppelin/contracts/utils/Strings.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)

pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library Strings {
    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: @openzeppelin/contracts/utils/introspection/ERC165.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

pragma solidity ^0.8.0;

import "./IERC165.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 ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

// File: @openzeppelin/contracts/utils/introspection/IERC165.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 IERC165 {
    /**
     * @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: @openzeppelin/contracts/token/ERC721/IERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

import "../../utils/introspection/IERC165.sol";

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @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`.
     *
     * 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;

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

    /**
     * @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);
}

// File: @openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Metadata is IERC721 {
    /**
     * @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);
}