// File: contracts/FNDNFT721.sol



/*
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             .------------::::--  `oys+/::/+shhhhhhhdddddddddy/-////+shhhhhhhhhhhhhhhhhhhhhy
            .--------------:::::-` +ys+////+yhhhhhhhddddddddhy:-////+yhhhhhhhhhhhhhhhhhhhhhy
          `----------------::::::-`.ss+/:::+oyhhhhhhhhhhhhhhho`-////+shhhhhhhhhhhhhhhhhhhhhy
         .------------------:::::::.-so//::/+osyyyhhhhhhhhhys` -////+shhhhhhhhhhhhhhhhhhhhhy
       `.-------------------::/:::::..+o+////+oosssyyyyyyys+`  .////+shhhhhhhhhhhhhhhhhhhhhy
       .--------------------::/:::.`   -+o++++++oooosssss/.     `-//+shhhhhhhhhhhhhhhhhhhhyo
     .-------   ``````.......--`        `-/+ooooosso+/-`          `./++++///:::--...``hhhhyo
                                              `````
   *　
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*/

// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "@openzeppelin/contracts-upgradeable/introspection/ERC165Upgradeable.sol";
import "./mixins/OZ/ERC721Upgradeable.sol";

import "./mixins/FoundationTreasuryNode.sol";
import "./mixins/roles/FoundationAdminRole.sol";
import "./mixins/HasSecondarySaleFees.sol";
import "./mixins/NFT721Core.sol";
import "./mixins/NFT721Market.sol";
import "./mixins/NFT721Creator.sol";
import "./mixins/NFT721Metadata.sol";
import "./mixins/NFT721Mint.sol";

/**
 * @title Foundation NFTs implemented using the ERC-721 standard.
 * @dev This top level file holds no data directly to ease future upgrades.
 */
contract FNDNFT721 is
  FoundationTreasuryNode,
  FoundationAdminRole,
  ERC165Upgradeable,
  HasSecondarySaleFees,
  ERC721Upgradeable,
  NFT721Core,
  NFT721Creator,
  NFT721Market,
  NFT721Metadata,
  NFT721Mint
{
  /**
   * @notice Called once to configure the contract after the initial deployment.
   * @dev This farms the initialize call out to inherited contracts as needed.
   */
  function initialize(
    address payable treasury,
    string memory name,
    string memory symbol
  ) public initializer {
    FoundationTreasuryNode._initializeFoundationTreasuryNode(treasury);

    ERC721Upgradeable.__ERC721_init(name, symbol);
    HasSecondarySaleFees._initializeHasSecondarySaleFees();
    NFT721Creator._initializeNFT721Creator();
    NFT721Mint._initializeNFT721Mint();
  }

  /**
   * @notice Allows a Foundation admin to update NFT config variables.
   * @dev This must be called right after the initial call to `initialize`.
   */
  function adminUpdateConfig(address _nftMarket, string memory baseURI) public onlyFoundationAdmin {
    _updateNFTMarket(_nftMarket);
    _updateBaseURI(baseURI);
  }

  /**
   * @dev This is a no-op, just an explicit override to address compile errors due to inheritance.
   */
  function _burn(uint256 tokenId)
    internal
    virtual
    override(ERC721Upgradeable, NFT721Creator, NFT721Metadata, NFT721Mint)
  {
    super._burn(tokenId);
  }
}

// File: @openzeppelin/contracts-upgradeable/introspection/ERC165Upgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

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

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts may inherit from this and call {_registerInterface} to declare
 * their support of an interface.
 */
abstract contract ERC165Upgradeable is Initializable, IERC165Upgradeable {
    /*
     * bytes4(keccak256('supportsInterface(bytes4)')) == 0x01ffc9a7
     */
    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;

    /**
     * @dev Mapping of interface ids to whether or not it's supported.
     */
    mapping(bytes4 => bool) private _supportedInterfaces;

    function __ERC165_init() internal initializer {
        __ERC165_init_unchained();
    }

    function __ERC165_init_unchained() internal initializer {
        // Derived contracts need only register support for their own interfaces,
        // we register support for ERC165 itself here
        _registerInterface(_INTERFACE_ID_ERC165);
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     *
     * Time complexity O(1), guaranteed to always use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return _supportedInterfaces[interfaceId];
    }

    /**
     * @dev Registers the contract as an implementer of the interface defined by
     * `interfaceId`. Support of the actual ERC165 interface is automatic and
     * registering its interface id is not required.
     *
     * See {IERC165-supportsInterface}.
     *
     * Requirements:
     *
     * - `interfaceId` cannot be the ERC165 invalid interface (`0xffffffff`).
     */
    function _registerInterface(bytes4 interfaceId) internal virtual {
        require(interfaceId != 0xffffffff, "ERC165: invalid interface id");
        _supportedInterfaces[interfaceId] = true;
    }
    uint256[49] private __gap;
}

// File: contracts/mixins/OZ/ERC721Upgradeable.sol



// SPDX-License-Identifier: MIT
// solhint-disable

/**
 * Copied from the OpenZeppelin repository in order to make `_tokenURIs` internal instead of private.
 */

pragma solidity >=0.6.0 <0.8.0;

import "@openzeppelin/contracts-upgradeable/token/ERC721/IERC721Upgradeable.sol";
import "@openzeppelin/contracts-upgradeable/token/ERC721/IERC721MetadataUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/token/ERC721/IERC721EnumerableUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/token/ERC721/IERC721ReceiverUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/introspection/ERC165Upgradeable.sol";
import "@openzeppelin/contracts-upgradeable/math/SafeMathUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/ContextUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/EnumerableSetUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/EnumerableMapUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/StringsUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";

/**
 * @title ERC721 Non-Fungible Token Standard basic implementation
 * @dev see https://eips.ethereum.org/EIPS/eip-721
 */
contract ERC721Upgradeable is
  Initializable,
  ContextUpgradeable,
  ERC165Upgradeable,
  IERC721Upgradeable,
  IERC721MetadataUpgradeable,
  IERC721EnumerableUpgradeable
{
  using SafeMathUpgradeable for uint256;
  using AddressUpgradeable for address;
  using EnumerableSetUpgradeable for EnumerableSetUpgradeable.UintSet;
  using EnumerableMapUpgradeable for EnumerableMapUpgradeable.UintToAddressMap;
  using StringsUpgradeable for uint256;

  // 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 holder address to their (enumerable) set of owned tokens
  mapping(address => EnumerableSetUpgradeable.UintSet) private _holderTokens;

  // Enumerable mapping from token ids to their owners
  EnumerableMapUpgradeable.UintToAddressMap private _tokenOwners;

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

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

  // Token name
  string private _name;

  // Token symbol
  string private _symbol;

  // Optional mapping for token URIs
  mapping(uint256 => string) internal _tokenURIs;

  // Base URI
  string private _baseURI;

  /*
   *     bytes4(keccak256('balanceOf(address)')) == 0x70a08231
   *     bytes4(keccak256('ownerOf(uint256)')) == 0x6352211e
   *     bytes4(keccak256('approve(address,uint256)')) == 0x095ea7b3
   *     bytes4(keccak256('getApproved(uint256)')) == 0x081812fc
   *     bytes4(keccak256('setApprovalForAll(address,bool)')) == 0xa22cb465
   *     bytes4(keccak256('isApprovedForAll(address,address)')) == 0xe985e9c5
   *     bytes4(keccak256('transferFrom(address,address,uint256)')) == 0x23b872dd
   *     bytes4(keccak256('safeTransferFrom(address,address,uint256)')) == 0x42842e0e
   *     bytes4(keccak256('safeTransferFrom(address,address,uint256,bytes)')) == 0xb88d4fde
   *
   *     => 0x70a08231 ^ 0x6352211e ^ 0x095ea7b3 ^ 0x081812fc ^
   *        0xa22cb465 ^ 0xe985e9c5 ^ 0x23b872dd ^ 0x42842e0e ^ 0xb88d4fde == 0x80ac58cd
   */
  bytes4 private constant _INTERFACE_ID_ERC721 = 0x80ac58cd;

  /*
   *     bytes4(keccak256('name()')) == 0x06fdde03
   *     bytes4(keccak256('symbol()')) == 0x95d89b41
   *     bytes4(keccak256('tokenURI(uint256)')) == 0xc87b56dd
   *
   *     => 0x06fdde03 ^ 0x95d89b41 ^ 0xc87b56dd == 0x5b5e139f
   */
  bytes4 private constant _INTERFACE_ID_ERC721_METADATA = 0x5b5e139f;

  /*
   *     bytes4(keccak256('totalSupply()')) == 0x18160ddd
   *     bytes4(keccak256('tokenOfOwnerByIndex(address,uint256)')) == 0x2f745c59
   *     bytes4(keccak256('tokenByIndex(uint256)')) == 0x4f6ccce7
   *
   *     => 0x18160ddd ^ 0x2f745c59 ^ 0x4f6ccce7 == 0x780e9d63
   */
  bytes4 private constant _INTERFACE_ID_ERC721_ENUMERABLE = 0x780e9d63;

  /**
   * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
   */
  function __ERC721_init(string memory name_, string memory symbol_) internal initializer {
    __Context_init_unchained();
    __ERC165_init_unchained();
    __ERC721_init_unchained(name_, symbol_);
  }

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

    // register the supported interfaces to conform to ERC721 via ERC165
    _registerInterface(_INTERFACE_ID_ERC721);
    _registerInterface(_INTERFACE_ID_ERC721_METADATA);
    _registerInterface(_INTERFACE_ID_ERC721_ENUMERABLE);
  }

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

    return _holderTokens[owner].length();
  }

  /**
   * @dev See {IERC721-ownerOf}.
   */
  function ownerOf(uint256 tokenId) public view override returns (address) {
    return _tokenOwners.get(tokenId, "ERC721: owner query for nonexistent token");
  }

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

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

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

    string memory _tokenURI = _tokenURIs[tokenId];

    // If there is no base URI, return the token URI.
    if (bytes(_baseURI).length == 0) {
      return _tokenURI;
    }
    // If both are set, concatenate the baseURI and tokenURI (via abi.encodePacked).
    if (bytes(_tokenURI).length > 0) {
      return string(abi.encodePacked(_baseURI, _tokenURI));
    }
    // If there is a baseURI but no tokenURI, concatenate the tokenID to the baseURI.
    return string(abi.encodePacked(_baseURI, tokenId.toString()));
  }

  /**
   * @dev Returns the base URI set via {_setBaseURI}. This will be
   * automatically added as a prefix in {tokenURI} to each token's URI, or
   * to the token ID if no specific URI is set for that token ID.
   */
  function baseURI() public view returns (string memory) {
    return _baseURI;
  }

  /**
   * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
   */
  function tokenOfOwnerByIndex(address owner, uint256 index) public view override returns (uint256) {
    return _holderTokens[owner].at(index);
  }

  /**
   * @dev See {IERC721Enumerable-totalSupply}.
   */
  function totalSupply() public view override returns (uint256) {
    // _tokenOwners are indexed by tokenIds, so .length() returns the number of tokenIds
    return _tokenOwners.length();
  }

  /**
   * @dev See {IERC721Enumerable-tokenByIndex}.
   */
  function tokenByIndex(uint256 index) public view override returns (uint256) {
    (uint256 tokenId, ) = _tokenOwners.at(index);
    return tokenId;
  }

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

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

    _approve(to, tokenId);
  }

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

    return _tokenApprovals[tokenId];
  }

  /**
   * @dev See {IERC721-setApprovalForAll}.
   */
  function setApprovalForAll(address operator, bool approved) public virtual override {
    require(operator != _msgSender(), "ERC721: approve to caller");

    _operatorApprovals[_msgSender()][operator] = approved;
    emit ApprovalForAll(_msgSender(), operator, approved);
  }

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

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

    _transfer(from, to, tokenId);
  }

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

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

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

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

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

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

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

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

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

    _holderTokens[to].add(tokenId);

    _tokenOwners.set(tokenId, to);

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

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

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

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

    // Clear metadata (if any)
    if (bytes(_tokenURIs[tokenId]).length != 0) {
      delete _tokenURIs[tokenId];
    }

    _holderTokens[owner].remove(tokenId);

    _tokenOwners.remove(tokenId);

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

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

    _beforeTokenTransfer(from, to, tokenId);

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

    _holderTokens[from].remove(tokenId);
    _holderTokens[to].add(tokenId);

    _tokenOwners.set(tokenId, to);

    emit Transfer(from, to, tokenId);
  }

  /**
   * @dev Sets `_tokenURI` as the tokenURI of `tokenId`.
   *
   * Requirements:
   *
   * - `tokenId` must exist.
   */
  function _setTokenURI(uint256 tokenId, string memory _tokenURI) internal virtual {
    require(_exists(tokenId), "ERC721Metadata: URI set of nonexistent token");
    _tokenURIs[tokenId] = _tokenURI;
  }

  /**
   * @dev Internal function to set the base URI for all token IDs. It is
   * automatically added as a prefix to the value returned in {tokenURI},
   * or to the token ID if {tokenURI} is empty.
   */
  function _setBaseURI(string memory baseURI_) internal virtual {
    _baseURI = baseURI_;
  }

  /**
   * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
   * The call is not executed if the target address is not a contract.
   *
   * @param from address representing the previous owner of the given token ID
   * @param to target address that will receive the tokens
   * @param tokenId uint256 ID of the token to be transferred
   * @param _data bytes optional data to send along with the call
   * @return bool whether the call correctly returned the expected magic value
   */
  function _checkOnERC721Received(
    address from,
    address to,
    uint256 tokenId,
    bytes memory _data
  ) private returns (bool) {
    if (!to.isContract()) {
      return true;
    }
    bytes memory returndata =
      to.functionCall(
        abi.encodeWithSelector(
          IERC721ReceiverUpgradeable(to).onERC721Received.selector,
          _msgSender(),
          from,
          tokenId,
          _data
        ),
        "ERC721: transfer to non ERC721Receiver implementer"
      );
    bytes4 retval = abi.decode(returndata, (bytes4));
    return (retval == _ERC721_RECEIVED);
  }

  function _approve(address to, uint256 tokenId) private {
    _tokenApprovals[tokenId] = to;
    emit Approval(ownerOf(tokenId), to, tokenId);
  }

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

  uint256[41] private __gap;
}

// File: contracts/mixins/FoundationTreasuryNode.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";
import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";

/**
 * @notice A mixin that stores a reference to the Foundation treasury contract.
 */
abstract contract FoundationTreasuryNode is Initializable {
  using AddressUpgradeable for address payable;

  address payable private treasury;

  /**
   * @dev Called once after the initial deployment to set the Foundation treasury address.
   */
  function _initializeFoundationTreasuryNode(address payable _treasury) internal initializer {
    require(_treasury.isContract(), "FoundationTreasuryNode: Address is not a contract");
    treasury = _treasury;
  }

  /**
   * @notice Returns the address of the Foundation treasury.
   */
  function getFoundationTreasury() public view returns (address payable) {
    return treasury;
  }

  // `______gap` is added to each mixin to allow adding new data slots or additional mixins in an upgrade-safe way.
  uint256[2000] private __gap;
}

// File: contracts/mixins/roles/FoundationAdminRole.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "../../interfaces/IAdminRole.sol";

import "../FoundationTreasuryNode.sol";

/**
 * @notice Allows a contract to leverage an admin role defined by the Foundation contract.
 */
abstract contract FoundationAdminRole is FoundationTreasuryNode {
  // This file uses 0 data slots (other than what's included via FoundationTreasuryNode)

  modifier onlyFoundationAdmin() {
    require(
      IAdminRole(getFoundationTreasury()).isAdmin(msg.sender),
      "FoundationAdminRole: caller does not have the Admin role"
    );
    _;
  }
}

// File: contracts/mixins/HasSecondarySaleFees.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "@openzeppelin/contracts-upgradeable/introspection/ERC165Upgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";

/**
 * @notice An interface for communicating fees to 3rd party marketplaces.
 * @dev Originally implemented in mainnet contract 0x44d6e8933f8271abcf253c72f9ed7e0e4c0323b3
 */
abstract contract HasSecondarySaleFees is Initializable, ERC165Upgradeable {
  /*
   * bytes4(keccak256('getFeeBps(uint256)')) == 0x0ebd4c7f
   * bytes4(keccak256('getFeeRecipients(uint256)')) == 0xb9c4d9fb
   *
   * => 0x0ebd4c7f ^ 0xb9c4d9fb == 0xb7799584
   */
  bytes4 private constant _INTERFACE_ID_FEES = 0xb7799584;

  /**
   * @dev Called once after the initial deployment to register the interface with ERC165.
   */
  function _initializeHasSecondarySaleFees() internal initializer {
    _registerInterface(_INTERFACE_ID_FEES);
  }

  function getFeeRecipients(uint256 id) public view virtual returns (address payable[] memory);

  function getFeeBps(uint256 id) public view virtual returns (uint256[] memory);
}

// File: contracts/mixins/NFT721Core.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

/**
 * @notice A place for common modifiers and functions used by various NFT721 mixins, if any.
 * @dev This also leaves a gap which can be used to add a new mixin to the top of the inheritance tree.
 */
abstract contract NFT721Core {
  uint256[1000] private ______gap;
}

// File: contracts/mixins/NFT721Market.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";

import "../interfaces/IFNDNFTMarket.sol";

import "./FoundationTreasuryNode.sol";
import "./HasSecondarySaleFees.sol";
import "./NFT721Creator.sol";

/**
 * @notice Holds a reference to the Foundation Market and communicates fees to 3rd party marketplaces.
 */
abstract contract NFT721Market is FoundationTreasuryNode, HasSecondarySaleFees, NFT721Creator {
  using AddressUpgradeable for address;

  event NFTMarketUpdated(address indexed nftMarket);

  IFNDNFTMarket private nftMarket;

  /**
   * @notice Returns the address of the Foundation NFTMarket contract.
   */
  function getNFTMarket() public view returns (address) {
    return address(nftMarket);
  }

  function _updateNFTMarket(address _nftMarket) internal {
    require(_nftMarket.isContract(), "NFT721Market: Market address is not a contract");
    nftMarket = IFNDNFTMarket(_nftMarket);

    emit NFTMarketUpdated(_nftMarket);
  }

  /**
   * @notice Returns an array of recipient addresses to which fees should be sent.
   * The expected fee amount is communicated with `getFeeBps`.
   */
  function getFeeRecipients(uint256 id) public view override returns (address payable[] memory) {
    require(_exists(id), "ERC721Metadata: Query for nonexistent token");

    address payable[] memory result = new address payable[](2);
    result[0] = getFoundationTreasury();
    result[1] = getTokenCreatorPaymentAddress(id);
    return result;
  }

  /**
   * @notice Returns an array of fees in basis points.
   * The expected recipients is communicated with `getFeeRecipients`.
   */
  function getFeeBps(
    uint256 /* id */
  ) public view override returns (uint256[] memory) {
    (, uint256 secondaryF8nFeeBasisPoints, uint256 secondaryCreatorFeeBasisPoints) = nftMarket.getFeeConfig();
    uint256[] memory result = new uint256[](2);
    result[0] = secondaryF8nFeeBasisPoints;
    result[1] = secondaryCreatorFeeBasisPoints;
    return result;
  }

  /**
   * @notice Get fee recipients and fees in a single call.
   * The data is the same as when calling getFeeRecipients and getFeeBps separately.
   */
  function getFees(uint256 tokenId)
    public
    view
    returns (address payable[2] memory recipients, uint256[2] memory feesInBasisPoints)
  {
    require(_exists(tokenId), "ERC721Metadata: Query for nonexistent token");

    recipients[0] = getFoundationTreasury();
    recipients[1] = getTokenCreatorPaymentAddress(tokenId);
    (, uint256 secondaryF8nFeeBasisPoints, uint256 secondaryCreatorFeeBasisPoints) = nftMarket.getFeeConfig();
    feesInBasisPoints[0] = secondaryF8nFeeBasisPoints;
    feesInBasisPoints[1] = secondaryCreatorFeeBasisPoints;
  }

  uint256[1000] private ______gap;
}

// File: contracts/mixins/NFT721Creator.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";
import "./OZ/ERC721Upgradeable.sol";

/**
 * @notice Allows each token to be associated with a creator.
 */
abstract contract NFT721Creator is Initializable, ERC721Upgradeable {
  mapping(uint256 => address payable) private tokenIdToCreator;

  /**
   * @dev Stores an optional alternate address to receive creator revenue and royalty payments.
   */
  mapping(uint256 => address payable) private tokenIdToCreatorPaymentAddress;

  event TokenCreatorUpdated(address indexed fromCreator, address indexed toCreator, uint256 indexed tokenId);

  event TokenCreatorPaymentAddressSet(
    address indexed fromPaymentAddress,
    address indexed toPaymentAddress,
    uint256 indexed tokenId
  );

  /*
   * bytes4(keccak256('tokenCreator(uint256)')) == 0x40c1a064
   */
  bytes4 private constant _INTERFACE_TOKEN_CREATOR = 0x40c1a064;

  /*
   * bytes4(keccak256('getTokenCreatorPaymentAddress(uint256)')) == 0xec5f752e;
   */
  bytes4 private constant _INTERFACE_TOKEN_CREATOR_PAYMENT_ADDRESS = 0xec5f752e;

  modifier onlyCreatorAndOwner(uint256 tokenId) {
    require(tokenIdToCreator[tokenId] == msg.sender, "NFT721Creator: Caller is not creator");
    require(ownerOf(tokenId) == msg.sender, "NFT721Creator: Caller does not own the NFT");
    _;
  }

  /**
   * @dev Called once after the initial deployment to register the interface with ERC165.
   */
  function _initializeNFT721Creator() internal initializer {
    _registerInterface(_INTERFACE_TOKEN_CREATOR);
  }

  /**
   * @notice Allows ERC165 interfaces which were not included originally to be registered.
   * @dev Currently this is the only new interface, but later other mixins can overload this function to do the same.
   */
  function registerInterfaces() public {
    _registerInterface(_INTERFACE_TOKEN_CREATOR_PAYMENT_ADDRESS);
  }

  /**
   * @notice Returns the creator's address for a given tokenId.
   */
  function tokenCreator(uint256 tokenId) public view returns (address payable) {
    return tokenIdToCreator[tokenId];
  }

  /**
   * @notice Returns the payment address for a given tokenId.
   * @dev If an alternate address was not defined, the creator is returned instead.
   */
  function getTokenCreatorPaymentAddress(uint256 tokenId)
    public
    view
    returns (address payable tokenCreatorPaymentAddress)
  {
    tokenCreatorPaymentAddress = tokenIdToCreatorPaymentAddress[tokenId];
    if (tokenCreatorPaymentAddress == address(0)) {
      tokenCreatorPaymentAddress = tokenIdToCreator[tokenId];
    }
  }

  function _updateTokenCreator(uint256 tokenId, address payable creator) internal {
    emit TokenCreatorUpdated(tokenIdToCreator[tokenId], creator, tokenId);

    tokenIdToCreator[tokenId] = creator;
  }

  /**
   * @dev Allow setting a different address to send payments to for both primary sale revenue
   * and secondary sales royalties.
   * This is immutable since it's only exposed publicly when minting a new NFT.
   */
  function _setTokenCreatorPaymentAddress(uint256 tokenId, address payable tokenCreatorPaymentAddress) internal {
    if (tokenCreatorPaymentAddress != address(0)) {
      tokenIdToCreatorPaymentAddress[tokenId] = tokenCreatorPaymentAddress;
      emit TokenCreatorPaymentAddressSet(address(0), tokenCreatorPaymentAddress, tokenId);
    }
  }

  /**
   * @notice Allows the creator to burn if they currently own the NFT.
   */
  function burn(uint256 tokenId) public onlyCreatorAndOwner(tokenId) {
    _burn(tokenId);
  }

  /**
   * @dev Remove the creator record when burned.
   */
  function _burn(uint256 tokenId) internal virtual override {
    delete tokenIdToCreator[tokenId];

    super._burn(tokenId);
  }

  uint256[999] private ______gap;
}

// File: contracts/mixins/NFT721Metadata.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "@openzeppelin/contracts-upgradeable/utils/StringsUpgradeable.sol";

import "./NFT721Core.sol";
import "./NFT721Creator.sol";

/**
 * @notice A mixin to extend the OpenZeppelin metadata implementation.
 */
abstract contract NFT721Metadata is NFT721Creator {
  using StringsUpgradeable for uint256;

  /**
   * @dev Stores hashes minted by a creator to prevent duplicates.
   */
  mapping(address => mapping(string => bool)) private creatorToIPFSHashToMinted;

  event BaseURIUpdated(string baseURI);
  event TokenIPFSPathUpdated(uint256 indexed tokenId, string indexed indexedTokenIPFSPath, string tokenIPFSPath);
  // This event was used in an order version of the contract
  event NFTMetadataUpdated(string name, string symbol, string baseURI);

  /**
   * @notice Returns the IPFSPath to the metadata JSON file for a given NFT.
   */
  function getTokenIPFSPath(uint256 tokenId) public view returns (string memory) {
    return _tokenURIs[tokenId];
  }

  /**
   * @notice Checks if the creator has already minted a given NFT.
   */
  function getHasCreatorMintedIPFSHash(address creator, string memory tokenIPFSPath) public view returns (bool) {
    return creatorToIPFSHashToMinted[creator][tokenIPFSPath];
  }

  function _updateBaseURI(string memory _baseURI) internal {
    _setBaseURI(_baseURI);

    emit BaseURIUpdated(_baseURI);
  }

  /**
   * @dev The IPFS path should be the CID + file.extension, e.g.
   * `QmfPsfGwLhiJrU8t9HpG4wuyjgPo9bk8go4aQqSu9Qg4h7/metadata.json`
   */
  function _setTokenIPFSPath(uint256 tokenId, string memory _tokenIPFSPath) internal {
    // 46 is the minimum length for an IPFS content hash, it may be longer if paths are used
    require(bytes(_tokenIPFSPath).length >= 46, "NFT721Metadata: Invalid IPFS path");
    require(!creatorToIPFSHashToMinted[msg.sender][_tokenIPFSPath], "NFT721Metadata: NFT was already minted");

    creatorToIPFSHashToMinted[msg.sender][_tokenIPFSPath] = true;
    _setTokenURI(tokenId, _tokenIPFSPath);
  }

  /**
   * @dev When a token is burned, remove record of it allowing that creator to re-mint the same NFT again in the future.
   */
  function _burn(uint256 tokenId) internal virtual override {
    delete creatorToIPFSHashToMinted[msg.sender][_tokenURIs[tokenId]];
    super._burn(tokenId);
  }

  uint256[999] private ______gap;
}

// File: contracts/mixins/NFT721Mint.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

import "./OZ/ERC721Upgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";
import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";

import "./NFT721Creator.sol";
import "./NFT721Market.sol";
import "./NFT721Metadata.sol";

/**
 * @notice Allows creators to mint NFTs.
 */
abstract contract NFT721Mint is Initializable, ERC721Upgradeable, NFT721Creator, NFT721Market, NFT721Metadata {
  using AddressUpgradeable for address;

  uint256 private nextTokenId;

  event Minted(
    address indexed creator,
    uint256 indexed tokenId,
    string indexed indexedTokenIPFSPath,
    string tokenIPFSPath
  );

  /**
   * @notice Gets the tokenId of the next NFT minted.
   */
  function getNextTokenId() public view returns (uint256) {
    return nextTokenId;
  }

  /**
   * @dev Called once after the initial deployment to set the initial tokenId.
   */
  function _initializeNFT721Mint() internal initializer {
    // Use ID 1 for the first NFT tokenId
    nextTokenId = 1;
  }

  /**
   * @notice Allows a creator to mint an NFT.
   */
  function mint(string memory tokenIPFSPath) public returns (uint256 tokenId) {
    tokenId = nextTokenId++;
    _mint(msg.sender, tokenId);
    _updateTokenCreator(tokenId, msg.sender);
    _setTokenIPFSPath(tokenId, tokenIPFSPath);
    emit Minted(msg.sender, tokenId, tokenIPFSPath, tokenIPFSPath);
  }

  /**
   * @notice Allows a creator to mint an NFT and set approval for the Foundation marketplace.
   * This can be used by creators the first time they mint an NFT to save having to issue a separate
   * approval transaction before starting an auction.
   */
  function mintAndApproveMarket(string memory tokenIPFSPath) public returns (uint256 tokenId) {
    tokenId = mint(tokenIPFSPath);
    setApprovalForAll(getNFTMarket(), true);
  }

  /**
   * @notice Allows a creator to mint an NFT and have creator revenue/royalties sent to an alternate address.
   */
  function mintWithCreatorPaymentAddress(string memory tokenIPFSPath, address payable tokenCreatorPaymentAddress)
    public
    returns (uint256 tokenId)
  {
    require(tokenCreatorPaymentAddress != address(0), "NFT721Mint: tokenCreatorPaymentAddress is required");
    tokenId = mint(tokenIPFSPath);
    _setTokenCreatorPaymentAddress(tokenId, tokenCreatorPaymentAddress);
  }

  /**
   * @notice Allows a creator to mint an NFT and have creator revenue/royalties sent to an alternate address.
   * Also sets approval for the Foundation marketplace.  This can be used by creators the first time they mint an NFT to
   * save having to issue a separate approval transaction before starting an auction.
   */
  function mintWithCreatorPaymentAddressAndApproveMarket(
    string memory tokenIPFSPath,
    address payable tokenCreatorPaymentAddress
  ) public returns (uint256 tokenId) {
    tokenId = mintWithCreatorPaymentAddress(tokenIPFSPath, tokenCreatorPaymentAddress);
    setApprovalForAll(getNFTMarket(), true);
  }

  /**
   * @notice Allows a creator to mint an NFT and have creator revenue/royalties sent to an alternate address
   * which is defined by a contract call, typically a proxy contract address representing the payment terms.
   */
  function mintWithCreatorPaymentFactory(
    string memory tokenIPFSPath,
    address paymentAddressFactory,
    bytes memory paymentAddressCallData
  ) public returns (uint256 tokenId) {
    bytes memory returnData = paymentAddressFactory.functionCall(paymentAddressCallData);
    address payable tokenCreatorPaymentAddress;
    // solhint-disable-next-line no-inline-assembly
    assembly {
      tokenCreatorPaymentAddress := mload(add(returnData, 32))
    }
    tokenId = mintWithCreatorPaymentAddress(tokenIPFSPath, tokenCreatorPaymentAddress);
  }

  /**
   * @notice Allows a creator to mint an NFT and have creator revenue/royalties sent to an alternate address
   * which is defined by a contract call, typically a proxy contract address representing the payment terms.
   * Also sets approval for the Foundation marketplace.  This can be used by creators the first time they mint an NFT to
   * save having to issue a separate approval transaction before starting an auction.
   */
  function mintWithCreatorPaymentFactoryAndApproveMarket(
    string memory tokenIPFSPath,
    address paymentAddressFactory,
    bytes memory paymentAddressCallData
  ) public returns (uint256 tokenId) {
    tokenId = mintWithCreatorPaymentFactory(tokenIPFSPath, paymentAddressFactory, paymentAddressCallData);
    setApprovalForAll(getNFTMarket(), true);
  }

  /**
   * @dev Explicit override to address compile errors.
   */
  function _burn(uint256 tokenId) internal virtual override(ERC721Upgradeable, NFT721Creator, NFT721Metadata) {
    super._burn(tokenId);
  }

  uint256[1000] private ______gap;
}

// File: @openzeppelin/contracts-upgradeable/introspection/IERC165Upgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

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

// File: @openzeppelin/contracts-upgradeable/proxy/Initializable.sol



// SPDX-License-Identifier: MIT

// solhint-disable-next-line compiler-version
pragma solidity >=0.4.24 <0.8.0;

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

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {UpgradeableProxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 */
abstract contract Initializable {

    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

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

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        require(_initializing || _isConstructor() || !_initialized, "Initializable: contract is already initialized");

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

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }

    /// @dev Returns true if and only if the function is running in the constructor
    function _isConstructor() private view returns (bool) {
        return !AddressUpgradeable.isContract(address(this));
    }
}

// File: @openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Collection of functions related to the address type
 */
library AddressUpgradeable {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    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);
    }

    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: @openzeppelin/contracts-upgradeable/token/ERC721/IERC721Upgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

// File: @openzeppelin/contracts-upgradeable/token/ERC721/IERC721MetadataUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "./IERC721Upgradeable.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721MetadataUpgradeable is IERC721Upgradeable {

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

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

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

// File: @openzeppelin/contracts-upgradeable/token/ERC721/IERC721EnumerableUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

import "./IERC721Upgradeable.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721EnumerableUpgradeable is IERC721Upgradeable {

    /**
     * @dev Returns the total amount of tokens stored by the contract.
     */
    function totalSupply() external view returns (uint256);

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

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

// File: @openzeppelin/contracts-upgradeable/token/ERC721/IERC721ReceiverUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

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

// File: @openzeppelin/contracts-upgradeable/math/SafeMathUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMathUpgradeable {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts-upgradeable/utils/ContextUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;
import "../proxy/Initializable.sol";

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with 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 ContextUpgradeable is Initializable {
    function __Context_init() internal initializer {
        __Context_init_unchained();
    }

    function __Context_init_unchained() internal initializer {
    }
    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;
    }
    uint256[50] private __gap;
}

// File: @openzeppelin/contracts-upgradeable/utils/EnumerableSetUpgradeable.sol



// 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 EnumerableSetUpgradeable {
    // 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));
    }
}

// File: @openzeppelin/contracts-upgradeable/utils/EnumerableMapUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev Library for managing an enumerable variant of Solidity's
 * https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`]
 * type.
 *
 * Maps have the following properties:
 *
 * - Entries are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Entries are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableMap for EnumerableMap.UintToAddressMap;
 *
 *     // Declare a set state variable
 *     EnumerableMap.UintToAddressMap private myMap;
 * }
 * ```
 *
 * As of v3.0.0, only maps of type `uint256 -> address` (`UintToAddressMap`) are
 * supported.
 */
library EnumerableMapUpgradeable {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Map type with
    // bytes32 keys and values.
    // The Map implementation uses private functions, and user-facing
    // implementations (such as Uint256ToAddressMap) are just wrappers around
    // the underlying Map.
    // This means that we can only create new EnumerableMaps for types that fit
    // in bytes32.

    struct MapEntry {
        bytes32 _key;
        bytes32 _value;
    }

    struct Map {
        // Storage of map keys and values
        MapEntry[] _entries;

        // Position of the entry defined by a key in the `entries` array, plus 1
        // because index 0 means a key is not in the map.
        mapping (bytes32 => uint256) _indexes;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function _set(Map storage map, bytes32 key, bytes32 value) private returns (bool) {
        // We read and store the key's index to prevent multiple reads from the same storage slot
        uint256 keyIndex = map._indexes[key];

        if (keyIndex == 0) { // Equivalent to !contains(map, key)
            map._entries.push(MapEntry({ _key: key, _value: value }));
            // The entry is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            map._indexes[key] = map._entries.length;
            return true;
        } else {
            map._entries[keyIndex - 1]._value = value;
            return false;
        }
    }

    /**
     * @dev Removes a key-value pair from a map. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function _remove(Map storage map, bytes32 key) private returns (bool) {
        // We read and store the key's index to prevent multiple reads from the same storage slot
        uint256 keyIndex = map._indexes[key];

        if (keyIndex != 0) { // Equivalent to contains(map, key)
            // To delete a key-value pair from the _entries array in O(1), we swap the entry to delete with the last one
            // in the array, and then remove the last entry (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = keyIndex - 1;
            uint256 lastIndex = map._entries.length - 1;

            // When the entry 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.

            MapEntry storage lastEntry = map._entries[lastIndex];

            // Move the last entry to the index where the entry to delete is
            map._entries[toDeleteIndex] = lastEntry;
            // Update the index for the moved entry
            map._indexes[lastEntry._key] = toDeleteIndex + 1; // All indexes are 1-based

            // Delete the slot where the moved entry was stored
            map._entries.pop();

            // Delete the index for the deleted slot
            delete map._indexes[key];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function _contains(Map storage map, bytes32 key) private view returns (bool) {
        return map._indexes[key] != 0;
    }

    /**
     * @dev Returns the number of key-value pairs in the map. O(1).
     */
    function _length(Map storage map) private view returns (uint256) {
        return map._entries.length;
    }

   /**
    * @dev Returns the key-value pair stored at position `index` in the map. O(1).
    *
    * Note that there are no guarantees on the ordering of entries inside the
    * array, and it may change when more entries are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Map storage map, uint256 index) private view returns (bytes32, bytes32) {
        require(map._entries.length > index, "EnumerableMap: index out of bounds");

        MapEntry storage entry = map._entries[index];
        return (entry._key, entry._value);
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     */
    function _tryGet(Map storage map, bytes32 key) private view returns (bool, bytes32) {
        uint256 keyIndex = map._indexes[key];
        if (keyIndex == 0) return (false, 0); // Equivalent to contains(map, key)
        return (true, map._entries[keyIndex - 1]._value); // All indexes are 1-based
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function _get(Map storage map, bytes32 key) private view returns (bytes32) {
        uint256 keyIndex = map._indexes[key];
        require(keyIndex != 0, "EnumerableMap: nonexistent key"); // Equivalent to contains(map, key)
        return map._entries[keyIndex - 1]._value; // All indexes are 1-based
    }

    /**
     * @dev Same as {_get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {_tryGet}.
     */
    function _get(Map storage map, bytes32 key, string memory errorMessage) private view returns (bytes32) {
        uint256 keyIndex = map._indexes[key];
        require(keyIndex != 0, errorMessage); // Equivalent to contains(map, key)
        return map._entries[keyIndex - 1]._value; // All indexes are 1-based
    }

    // UintToAddressMap

    struct UintToAddressMap {
        Map _inner;
    }

    /**
     * @dev Adds a key-value pair to a map, or updates the value for an existing
     * key. O(1).
     *
     * Returns true if the key was added to the map, that is if it was not
     * already present.
     */
    function set(UintToAddressMap storage map, uint256 key, address value) internal returns (bool) {
        return _set(map._inner, bytes32(key), bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the key was removed from the map, that is if it was present.
     */
    function remove(UintToAddressMap storage map, uint256 key) internal returns (bool) {
        return _remove(map._inner, bytes32(key));
    }

    /**
     * @dev Returns true if the key is in the map. O(1).
     */
    function contains(UintToAddressMap storage map, uint256 key) internal view returns (bool) {
        return _contains(map._inner, bytes32(key));
    }

    /**
     * @dev Returns the number of elements in the map. O(1).
     */
    function length(UintToAddressMap storage map) internal view returns (uint256) {
        return _length(map._inner);
    }

   /**
    * @dev Returns the element 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(UintToAddressMap storage map, uint256 index) internal view returns (uint256, address) {
        (bytes32 key, bytes32 value) = _at(map._inner, index);
        return (uint256(key), address(uint160(uint256(value))));
    }

    /**
     * @dev Tries to returns the value associated with `key`.  O(1).
     * Does not revert if `key` is not in the map.
     *
     * _Available since v3.4._
     */
    function tryGet(UintToAddressMap storage map, uint256 key) internal view returns (bool, address) {
        (bool success, bytes32 value) = _tryGet(map._inner, bytes32(key));
        return (success, address(uint160(uint256(value))));
    }

    /**
     * @dev Returns the value associated with `key`.  O(1).
     *
     * Requirements:
     *
     * - `key` must be in the map.
     */
    function get(UintToAddressMap storage map, uint256 key) internal view returns (address) {
        return address(uint160(uint256(_get(map._inner, bytes32(key)))));
    }

    /**
     * @dev Same as {get}, with a custom error message when `key` is not in the map.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryGet}.
     */
    function get(UintToAddressMap storage map, uint256 key, string memory errorMessage) internal view returns (address) {
        return address(uint160(uint256(_get(map._inner, bytes32(key), errorMessage))));
    }
}

// File: @openzeppelin/contracts-upgradeable/utils/StringsUpgradeable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.7.0;

/**
 * @dev String operations.
 */
library StringsUpgradeable {
    /**
     * @dev Converts a `uint256` to its ASCII `string` 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);
        uint256 index = digits - 1;
        temp = value;
        while (temp != 0) {
            buffer[index--] = bytes1(uint8(48 + temp % 10));
            temp /= 10;
        }
        return string(buffer);
    }
}

// File: contracts/interfaces/IAdminRole.sol



// SPDX-License-Identifier: MIT OR Apache-2.0

pragma solidity ^0.7.0;

/**
 * @notice Interface for AdminRole which wraps the default admin role from
 * OpenZeppelin's AccessControl for easy integration.
 */
interface IAdminRole {
  function isAdmin(address account) external view returns (bool);
}

// File: contracts/interfaces/IFNDNFTMarket.sol



// SPDX-License-Identifier: MIT OR Apache-2.0
// solhint-disable

pragma solidity ^0.7.0;

interface IFNDNFTMarket {
  function getFeeConfig()
    external
    view
    returns (
      uint256 primaryF8nFeeBasisPoints,
      uint256 secondaryF8nFeeBasisPoints,
      uint256 secondaryCreatorFeeBasisPoints
    );
}