// File: ShatteredOpportunities.sol



// SPDX-License-Identifier: Apache-2.0

/// @notice Shattered Opportunities by Tim Maxwell
/// @author transientlabs.xyz

/**
_____/\\\\\\\\\\\____/\\\________________________________________________________________________________________________________/\\\__                                            
 ___/\\\/////////\\\_\/\\\_______________________________________________________________________________________________________\/\\\__                                           
  __\//\\\______\///__\/\\\____________________________/\\\__________/\\\_________________________________________________________\/\\\__                                          
   ___\////\\\_________\/\\\__________/\\\\\\\\\_____/\\\\\\\\\\\__/\\\\\\\\\\\_____/\\\\\\\\___/\\/\\\\\\\______/\\\\\\\\_________\/\\\__                                         
    ______\////\\\______\/\\\\\\\\\\__\////////\\\___\////\\\////__\////\\\////____/\\\/////\\\_\/\\\/////\\\___/\\\/////\\\___/\\\\\\\\\__                                        
     _________\////\\\___\/\\\/////\\\___/\\\\\\\\\\_____\/\\\_________\/\\\_______/\\\\\\\\\\\__\/\\\___\///___/\\\\\\\\\\\___/\\\////\\\__                                       
      __/\\\______\//\\\__\/\\\___\/\\\__/\\\/////\\\_____\/\\\_/\\_____\/\\\_/\\__\//\\///////___\/\\\_________\//\\///////___\/\\\__\/\\\__                                      
       _\///\\\\\\\\\\\/___\/\\\___\/\\\_\//\\\\\\\\/\\____\//\\\\\______\//\\\\\____\//\\\\\\\\\\_\/\\\__________\//\\\\\\\\\\_\//\\\\\\\/\\_                                     
        ___\///////////_____\///____\///___\////////\//______\/////________\/////______\//////////__\///____________\//////////___\///////\//__                                                                                                                                                                                                                                                                                                                                                                                       
                                                                                                                                                                                   
_______/\\\\\______________________________________________________________________________________________________________________________________________________________        
 _____/\\\///\\\____________________________________________________________________________________________________________________________________________________________       
  ___/\\\/__\///\\\____/\\\\\\\\\____/\\\\\\\\\__________________________________/\\\___________________________________/\\\_____/\\\_______/\\\_____________________________      
   __/\\\______\//\\\__/\\\/////\\\__/\\\/////\\\_____/\\\\\_____/\\/\\\\\\\___/\\\\\\\\\\\__/\\\____/\\\__/\\/\\\\\\___\///___/\\\\\\\\\\\_\///______/\\\\\\\\___/\\\\\\\\\\_     
    _\/\\\_______\/\\\_\/\\\\\\\\\\__\/\\\\\\\\\\____/\\\///\\\__\/\\\/////\\\_\////\\\////__\/\\\___\/\\\_\/\\\////\\\___/\\\_\////\\\////___/\\\___/\\\/////\\\_\/\\\//////__    
     _\//\\\______/\\\__\/\\\//////___\/\\\//////____/\\\__\//\\\_\/\\\___\///_____\/\\\______\/\\\___\/\\\_\/\\\__\//\\\_\/\\\____\/\\\______\/\\\__/\\\\\\\\\\\__\/\\\\\\\\\\_   
      __\///\\\__/\\\____\/\\\_________\/\\\_________\//\\\__/\\\__\/\\\____________\/\\\_/\\__\/\\\___\/\\\_\/\\\___\/\\\_\/\\\____\/\\\_/\\__\/\\\_\//\\///////___\////////\\\_  
       ____\///\\\\\/_____\/\\\_________\/\\\__________\///\\\\\/___\/\\\____________\//\\\\\___\//\\\\\\\\\__\/\\\___\/\\\_\/\\\____\//\\\\\___\/\\\__\//\\\\\\\\\\__/\\\\\\\\\\_ 
        ______\/////_______\///__________\///_____________\/////_____\///______________\/////_____\/////////___\///____\///__\///______\/////____\///____\//////////__\//////////__
*/

pragma solidity 0.8.14;

import "ShatterV2.sol";

contract ShatteredOpportunities is ShatterV2 {

    constructor (
        address royaltyRecipient,
        uint256 royaltyPercentage,
        address admin,
        uint256 num,
        uint256 time
    )
    ShatterV2(
        "Shattered Opportunities",
        "SHOPP",
        royaltyRecipient,
        royaltyPercentage,
        admin,
        num,
        time
    )
    {}

}
// File: ShatterV2.sol



// SPDX-License-Identifier: Apache-2.0

/// @title Shatter V2
/// @notice Shatter V2 where the original pieces Shatters into unique 1/1's. No Fuse functionality and owners don't choose number to shatter
/// @author transientlabs.xyz

pragma solidity 0.8.14;

/*
_____/\\\\\\\\\\\____/\\\_________________________________________________________________________________        
 ___/\\\/////////\\\_\/\\\_________________________________________________________________________________       
  __\//\\\______\///__\/\\\____________________________/\\\__________/\\\___________________________________      
   ___\////\\\_________\/\\\__________/\\\\\\\\\_____/\\\\\\\\\\\__/\\\\\\\\\\\_____/\\\\\\\\___/\\/\\\\\\\__     
    ______\////\\\______\/\\\\\\\\\\__\////////\\\___\////\\\////__\////\\\////____/\\\/////\\\_\/\\\/////\\\_    
     _________\////\\\___\/\\\/////\\\___/\\\\\\\\\\_____\/\\\_________\/\\\_______/\\\\\\\\\\\__\/\\\___\///__   
      __/\\\______\//\\\__\/\\\___\/\\\__/\\\/////\\\_____\/\\\_/\\_____\/\\\_/\\__\//\\///////___\/\\\_________  
       _\///\\\\\\\\\\\/___\/\\\___\/\\\_\//\\\\\\\\/\\____\//\\\\\______\//\\\\\____\//\\\\\\\\\\_\/\\\_________ 
        ___\///////////_____\///____\///___\////////\//______\/////________\/////______\//////////__\///__________
   ___       _ __   __  ___  _ ______                 __ 
  / _ )__ __(_) /__/ / / _ \(_) _/ _/__ _______ ___  / /_
 / _  / // / / / _  / / // / / _/ _/ -_) __/ -_) _ \/ __/
/____/\_,_/_/_/\_,_/ /____/_/_//_/ \__/_/  \__/_//_/\__/                                                          
 ______                  _          __    __        __     
/_  __/______ ____  ___ (_)__ ___  / /_  / /  ___ _/ /  ___
 / / / __/ _ `/ _ \(_-</ / -_) _ \/ __/ / /__/ _ `/ _ \(_-<
/_/ /_/  \_,_/_//_/___/_/\__/_//_/\__/ /____/\_,_/_.__/___/                                                           
*/

import "ERC721S.sol";
import "EIP2981AllToken.sol";
import "Ownable.sol";

contract ShatterV2 is ERC721S, EIP2981AllToken, Ownable {

    bool public isShattered;
    uint256 public numShatters;
    uint256 public shatters;
    uint256 public shatterTime;
    address public adminAddress;
    address private _shatterAddress;
    string private _baseUri;

    event Shattered(address indexed user, uint256 indexed numShatters, uint256 indexed shatteredTime);

    modifier adminOrOwner {
        address sender = _msgSender();
        require(sender == adminAddress || sender == owner(), "Address not admin or owner");
        _;
    }

    modifier onlyAdmin {
        require(_msgSender() == adminAddress, "Address not admin");
        _;
    }

    /// @param name is the name of the contract
    /// @param symbol is the contract symbol
    /// @param royaltyRecipient is the royalty recipient
    /// @param royaltyPercentage is the royalty percentage to set
    /// @param admin is the admin address
    /// @param num is the number of shatters that will happen
    /// @param time is time after which shatter can occur
    constructor (
        string memory name,
        string memory symbol,
        address royaltyRecipient,
        uint256 royaltyPercentage,
        address admin,
        uint256 num,
        uint256 time
    )
        ERC721S(name, symbol)
        EIP2981AllToken(royaltyRecipient, royaltyPercentage)
        Ownable()
    {
        require(num >= 1, "Cannot deploy a shatter contract with 0 shatters");
        adminAddress = admin;
        numShatters = num;
        shatterTime = time;
    }

    /// @notice function to change the royalty info
    /// @dev requires owner
    /// @dev this is useful if the amount was set improperly at contract creation.
    /// @param newAddr is the new royalty payout addresss
    /// @param newPerc is the new royalty percentage, in basis points (out of 10,000)
    function setRoyaltyInfo(address newAddr, uint256 newPerc) external onlyOwner {
        _setRoyaltyInfo(newAddr, newPerc);
    }

    /// @notice function to renounce admin rights
    /// @dev requires only admin
    function renounceAdmin() external onlyAdmin {
        adminAddress = address(0);
    }

    /// @notice function to set the admin address on the contract
    /// @dev requires owner
    /// @param newAdmin is the new admin address
    function setAdminAddress(address newAdmin) external onlyOwner {
        require(newAdmin != address(0), "New admin cannot be the zero address");
        adminAddress = newAdmin;
    }

    /// @notice function to set base uri
    /// @dev requires owner
    /// @param newUri is the new base uri
    function setBaseURI(string memory newUri) public onlyOwner {
        _setBaseUri(newUri);
    }

    /// @notice function for minting the 1/1 to the owner's address
    /// @dev requires contract owner or admin
    /// @dev sets the description, image, animation url (if exists), and traits for the piece
    /// @dev requires that shatters is equal to 0 -> meaning no piece has been minted
    /// @dev using _mint function as owner() should always be an EOA or trusted entity
    function mint(string memory newUri) external adminOrOwner {
        require(shatters == 0, "Already minted the first piece");
        _setBaseUri(newUri);
        shatters = 1;
        _mint(owner(), 0);
    }

    /// @notice function for owner of token 0 to unlock the pieces
    /// @dev requires msg.sender to be the owner of token 0
    /// @dev shatters to specified number of shatters
    /// @dev requires isShattered to be false
    /// @dev requires block timestamp to be greater than or equal to shatterTime
    /// @dev purposefully not letting approved addresses shatter as we want owner to be the only one to shatter the token
    function shatter() external {
        address sender = _msgSender();
        require(!isShattered, "Already is shattered");
        require(sender == ownerOf(0), "Caller is not owner of token 0");
        require(block.timestamp >= shatterTime, "Cannot shatter prior to shatterTime");

        _burn(0);
        _batchMint(sender, numShatters);

        // no reentrancy so can set these after burning and minting
        isShattered = true;
        shatters = numShatters;

        emit Shattered(msg.sender, numShatters, block.timestamp);

    }

    /// @notice overrides supportsInterface function
    /// @param interfaceId is supplied from anyone/contract calling this function, as defined in ERC 165
    /// @return boolean saying if this contract supports the interface or not
    function supportsInterface(bytes4 interfaceId) public view override(ERC721S, EIP2981AllToken) returns (bool) {
        return ERC721S.supportsInterface(interfaceId) || EIP2981AllToken.supportsInterface(interfaceId);
    }

    /// @notice function to override ownerOf in ERC721S
    /// @dev if is shattered and not fused, checks to see if that token has been transferred or if it belongs to the shatterAddress.
    ///     Otherwise, returns result from ERC721S.
    function ownerOf(uint256 tokenId) public view virtual override(ERC721S) returns (address) {
        if (isShattered) {
            if (tokenId > 0 && tokenId <= shatters) {
                address owner = _owners[tokenId];
                if (owner == address(0)) {
                    return _shatterAddress;
                } else {
                    return owner;
                }
            } else {
                revert("Invalid token id");
            }
        } else {
            return ERC721S.ownerOf(tokenId);
        }
    }

    /// @notice function to override the _exists function in ERC721S
    /// @dev if is shattered and not fused, checks to see if tokenId is in the range of shatters
    ///     otherwise, returns result from ERC721S
    function _exists(uint256 tokenId) internal view virtual override(ERC721S) returns (bool) {
        if (isShattered) {
            if (tokenId > 0 && tokenId <= shatters) {
                return true;
            } else {
                return false;
            }
        } else {
            return ERC721S._exists(tokenId);
        }
    }

    /// @notice function to batch mint upon shatter
    /// @dev only mints tokenIds 1 -> quantity to shatterExecutor
    function _batchMint(address shatterExecutor, uint256 quantity) internal {
        _shatterAddress = shatterExecutor;
        _balances[shatterExecutor] += quantity;
        for (uint256 id = 1; id < quantity + 1; id++) {
            emit Transfer(address(0), shatterExecutor, id);
        }
        // TODO replace with consecutive transfer
    }

    /// @notice function to set base uri internally
    function _setBaseUri(string memory newUri) internal {
        _baseUri = newUri;
    }

    /// @notice override _baseURI() function from ERC721A
    function _baseURI() internal view override returns (string memory) {
        return _baseUri;
    }
}
// File: ERC721S.sol



// SPDX-License-Identifier: MIT

/// @title ERC721S - an implementation of ERC721 for use in Shatter
/// @author transientlabs.xyz
/// @dev Transient Labs fork of OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/ERC721.sol)
///     for use in Shatter contracts. Changes are as follows to achieve an efficient batch mint while keeping transfer fees low:
///         1. `_owners` and `_balances` variable scope are `internal`
///         2. all calls to `ERC721.ownerOf` are replaced with just `ownerOf`
/// @dev we decided not to write our own base ERC721 contract as OpenZeppelin's implementation is the standard in the space

pragma solidity ^0.8.0;

import "IERC721.sol";
import "IERC721Receiver.sol";
import "IERC721Metadata.sol";
import "Address.sol";
import "Context.sol";
import "Strings.sol";
import "ERC165.sol";

/**
 * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
 * the Metadata extension, but not including the Enumerable extension, which is available separately as
 * {ERC721Enumerable}.
 */
contract ERC721S is Context, ERC165, IERC721, IERC721Metadata {
    using Address for address;
    using Strings for uint256;

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

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

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

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

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

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
        return
            interfaceId == type(IERC721).interfaceId ||
            interfaceId == type(IERC721Metadata).interfaceId ||
            super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721-balanceOf}.
     */
    function balanceOf(address owner) public view virtual override returns (uint256) {
        require(owner != address(0), "ERC721: address zero is not a valid owner");
        return _balances[owner];
    }

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

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

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

    /**
     * @dev See {IERC721Metadata-tokenURI}.
     */
    function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
        _requireMinted(tokenId);

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

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

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

        require(
            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
            "ERC721: approve caller is not token owner or approved for all"
        );

        _approve(to, tokenId);
    }

    /**
     * @dev See {IERC721-getApproved}.
     */
    function getApproved(uint256 tokenId) public view virtual override returns (address) {
        _requireMinted(tokenId);

        return _tokenApprovals[tokenId];
    }

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

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

    /**
     * @dev See {IERC721-transferFrom}.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) public virtual override {
        //solhint-disable-next-line max-line-length
        require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or 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: caller is not token owner or approved");
        _safeTransfer(from, to, tokenId, data);
    }

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

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

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

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

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

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

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

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

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

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

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     * This is an internal function that does not check if the sender is authorized to operate on the token.
     *
     * 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
        delete _tokenApprovals[tokenId];

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

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

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

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

        _beforeTokenTransfer(from, to, tokenId);

        // Clear approvals from the previous owner
        delete _tokenApprovals[tokenId];

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

        emit Transfer(from, to, tokenId);

        _afterTokenTransfer(from, to, tokenId);
    }

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

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

    /**
     * @dev Reverts if the `tokenId` has not been minted yet.
     */
    function _requireMinted(uint256 tokenId) internal view virtual {
        require(_exists(tokenId), "ERC721: invalid token ID");
    }

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

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

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual {}
}
// File: IERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

import "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 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: 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: IERC721Receiver.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @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 `IERC721Receiver.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

// File: 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);
}

// File: Address.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)

pragma solidity ^0.8.1;

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

        return account.code.length > 0;
    }

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

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

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

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

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

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

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

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

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

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

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

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

    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: 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: Strings.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)

pragma solidity ^0.8.0;

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**
     * @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);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}

// File: 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: EIP2981AllToken.sol



// SPDX-License-Identifier: MIT
/**
*   @title EIP 2981 All Token
*   @notice implementation of EIP 2981, with all tokens having the same royalty amount
*   @author transientlabs.xyz
*/

/*
   ___       _ __   __  ___  _ ______                 __ 
  / _ )__ __(_) /__/ / / _ \(_) _/ _/__ _______ ___  / /_
 / _  / // / / / _  / / // / / _/ _/ -_) __/ -_) _ \/ __/
/____/\_,_/_/_/\_,_/ /____/_/_//_/ \__/_/  \__/_//_/\__/                                                          
 ______                  _          __    __        __     
/_  __/______ ____  ___ (_)__ ___  / /_  / /  ___ _/ /  ___
 / / / __/ _ `/ _ \(_-</ / -_) _ \/ __/ / /__/ _ `/ _ \(_-<
/_/ /_/  \_,_/_//_/___/_/\__/_//_/\__/ /____/\_,_/_.__/___/ 
*/

pragma solidity >0.8.9 <0.9.0;

import "ERC165.sol";
import "IEIP2981.sol";

abstract contract EIP2981AllToken is IEIP2981, ERC165 {

    address internal _royaltyAddr;
    uint256 internal _royaltyPerc; // percentage in basis (out of 10,000)

    /**
    *   @param recipient is the royalty recipient
    *   @param percentage is the royalty percentage
    */
    constructor(address recipient, uint256 percentage) {
        _setRoyaltyInfo(recipient, percentage);
    }
    
    /**
    *   @notice EIP 2981 royalty support
    *   @dev royalty amount not dependent on _tokenId
    */
    function royaltyInfo(uint256 _tokenId, uint256 _salePrice) external view virtual override returns (address receiver, uint256 royaltyAmount) {
        return (_royaltyAddr, _royaltyPerc * _salePrice / 10000);
    }

    /**
    *   @notice override ERC 165 implementation of this function
    *   @dev if using this contract with another contract that suppports ERC 265, will have to override in the inheriting contract
    */
    function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165) returns (bool) {
        return interfaceId == type(IEIP2981).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
    *   @notice function to set royalty information
    *   @dev to be called by inheriting contract
    *   @param addr is the royalty payout address for this token id
    *   @param perc is the royalty percentage (out of 10,000) to set for this token id
    */
    function _setRoyaltyInfo(address addr, uint256 perc) internal virtual {
        require(addr != address(0), "EIP2981AllToken: Cannot set royalty receipient to the zero address");
        require(perc < 10000, "EIP2981AllToken: Cannot set royalty percentage above 10000");
        _royaltyAddr = addr;
        _royaltyPerc = perc;
    }
}
// File: IEIP2981.sol



// SPDX-License-Identifier: MIT

pragma solidity >0.8.9 <0.9.0;

///
/// @dev Interface for the NFT Royalty Standard
///
interface IEIP2981 {
    /// ERC165 bytes to add to interface array - set in parent contract
    /// implementing this standard
    ///
    /// bytes4(keccak256("royaltyInfo(uint256,uint256)")) == 0x2a55205a

    /// @notice Called with the sale price to determine how much royalty
    //          is owed and to whom.
    /// @param _tokenId - the NFT asset queried for royalty information
    /// @param _salePrice - the sale price of the NFT asset specified by _tokenId
    /// @return receiver - address of who should be sent the royalty payment
    /// @return royaltyAmount - the royalty payment amount for _salePrice
    function royaltyInfo(uint256 _tokenId, uint256 _salePrice) external view returns (address receiver,uint256 royaltyAmount);
}
// File: Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

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

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

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

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

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