// File: /contracts/EVADAO.sol



// SPDX-License-Identifier: MIT

// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWNNNNNNNNNNNNNNNNNNNNNNNNNNNWMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMXl'''''''''''''''''''''''''''lXMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; .:lllllllllc. .:lllllllc. ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMN: ,KMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMN: ,KMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMN: ,KMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMN: ,KMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMN: ,KMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMWklxNMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMK; ;XMMMMMMMMMMMMMMMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMNklkNMMMMMMMMMMMMMMMMMMMMMWklkNMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
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// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
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// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWNWMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNKOdl:'cXMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWNKkdl;'.  .';xNMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWX0kdoc;.. ..,:lxOKNMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWX0xoc,..  ..;cok0XWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMNd,'...':ldk0KNWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMK; 'ldkKWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMNx:,....,:lxkOKNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWXOxl:,.   .';ldkKNWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWXOkxoc,.. ..;cok0XWMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWX0koc,.. ..,dNMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWX0koc;lXMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWWMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
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// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMXc  .':ok0NWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX0xl:'. ..;clxOXWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNKx'  .....,cdkKNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,xO0xo:'...':ox0NWMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,kKMMMMWKOdl;'.',;xNMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,kKMMMMMMMMMN0xo; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,kKMMMWX0xl:'...':xNMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMN: 'dkkoc,.  .,cokKNMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWXOo.  .  ..;ldOXWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMWKko:,.  .':cox0NWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX:  .,cdOKWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMNkx0XWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMWWWWNKOkkkOXWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
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// MMMMMMMMMMMMMMMMMMMMMMMMNXNWWN0xxOKXXXNWWWWWWWWWWWWWWWWWWWWWMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMWWXXWWNNXXXNXXNWWWWWWWWWWWWWWWWWWWWWWNNXNWWMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMWNXXXKXXXXNNNNNNNXKXNNNWWWWWWWWWWWWWWWWWWWWNXXXWMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMWWWNNK0OO0000KKKXXXNNNNXKXNWWMMMWNNNWNNNWWWWWWWWWWWNNNWMMMMMMMMMMMMMM
// WWWWWWWWWWWWNNNXK0OkkkkkkO000KKKKKKKXK0KXXNNKKKKKXWX0XWWWWWWWWNNNNNNNNWMMMMMMMMMMMM
// WWWWWWWWNNNNNXXX0kxxxkOOOOOOO000K0000kkOOOOOxxOkkkOkddO000KXNNNNXXXXNNNWWMMMMMMMMMM
// WMMWWWWWNNNXXXXKkdddxkO0000000OOO0KXK0kkxxxkkkOkdl:;,;:loodkO0KKKKXXXXNXNWMMMMMMMMM
// WWWWWWNNXKKKKK0kooodxO00KKKKXNXOdONMMNKOxddxkO0Oxl;,,,,;:clddxkO0000KKXXKXWMMMMMMMM
// KKKK0OO00OOOkkdcclloxk0KXNNXXXNNOx0WMWNXK0OkOKXXKkl;;:::clloddxxkkkkO00KKKXMMMMMMMM
// kkkkkxxxxxddol:;:c::cldk0NWWX0O0NKxkNWNWNKkldKWWWNXKOkxxddooooooodxkkOOOOO0NMMMMMMM
// lllllllcc::;,'.',,,''',:ldkOOxlcdOkldO00OOl''o0XNNNWWNKOxocc::cllooodxkkkkkXMMMMMMM
// ;;,,,,,''................'',,,...,:,':lc;;;,'',:codddol:;;,,;;::::ccclodddx0WMMMMMM
// '.....................................''....................',,;;;;;;;:cclo0WMMMMMM
// ................................................................'''''..,;:oXMMMMMMM
// .........................................................................;OWMMMMMMM
// .........................................................................oNMMMMMMMM
// ........................................................................lXMMMMMMMMM
// ..........''',,'......................................................'dNMMMMMMMMMM
// lldddddoooll:;'.....................................................'l0WMMMMMMMMMMM
// MMMMMMMMMMMMWXKOxol:,'......,;,''.................................,cOWMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMWNKOdc;'.....''..............................',:dXMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMWKx;.................'''''..........',,;:ccdXMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMM0:.............',,,,,,'''...'',;cok00OkkkONMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMKl'.............;lllllloodxkO0KXWMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMWKkoc,.......:xNWWWWWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMN0kkOOOKWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
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// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMNx:::::::::::::::::::::::::::dNMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMK; .,;,;;,,;;;;;;;;;;,;;,;,. ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;KWWWWWWWWWWWWWWWWWWWWWX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMMMMMMMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ;XMMMMMMMMMMMMMMMMMMMMMX; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMN: '0MMMMMMMMMMMMMMMMMMMMM0' ;XMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMWd  oWMMMMMMMMMMMMMMMMMMMWo  oWMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX: .dNMMMMMMMMMMMMMMMMMNd. :XMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMK:  ;xXWMMMMMMMMMMMWXx;  cKMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNk;. .;lddxkOOkxdl;. .;kNMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMN0o:'.         .':d0WMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNX0OOkkkkO0KNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMXdcokKNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMNo.. .':lx0XWWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWX0xo:'.  .';ldOXWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMW0, .',.. .,cokKNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,kKN0koc,...':lx0XWMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,kKMMMMMWXOxl:,,,'oNMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,kKMMMMMMMWNKOxo; ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; ,kKMMWXOdl;'...':oOWMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; .coo:,.  .,cdkKNMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNKOd:.    .';lx0XWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMWOl:'.  .,codkKNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
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// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMWK0NWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
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// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWNXXK00KXNWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNOoc,.........,:oONMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMW0l'  .,:clooool:,.  .l0WMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMXl. .lkXWMMMMMMMMMWXkl' .lXMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMK; .oXMMMMMMMMMMMMMMMMMXo. ,KMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMNc .kWMMMMMMMMMMMMMMMMMMMWk. :XMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMk. lWMMMMMMMMMMMMMMMMMMMMMWo .kMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMd .xMMMMMMMMMMMMMMMMMMMMMMMx. dMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMk. oWMMMMMMMMMMMMMMMMMMMMMMd .xMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMX; '0MMMMMMMMMMMMMMMMMMMMM0, ,KMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMO. 'kWMMMMMMMMMMMMMMMMMWO, .kMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMW0; .;xXWMMMMMMMMMMMWXk:. ,OWMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNx;. .;ldxxOOOOkdl;.  ,xNMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMW0o:'.         .':oONMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNK0Okxxxxk0KNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
// MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM

pragma solidity ^0.8.0;

import "./ERC721EnumerableDelegable.sol";
import "@openzeppelin/contracts/interfaces/IERC2981.sol";
import "./BasisPoints.sol";
import "./IERC721Dispatcher.sol";

interface IEVADQ {
  function mint(address _owner, uint256 _tokenId) external;
}

/**
 * @title EVADAO
 * @dev EVADAO ERC721Delegable NFT contract.
 * @author 0xAnimist (kanon.art) for EVADAO
 */
contract EVADAO is ERC721EnumerableDelegable, IERC2981 {

  address public admin;

  IEVADQ private evaDQ;

  struct Artwork {
    address[] artists;
    string tokenUri;
    string gatedUri;
    bool gatedUriLocked;
  }

  mapping(uint256 => Artwork) private _artworks;

  struct RoyaltyInfo {
    address receiver;
    uint256 royaltyInBp;
  }

  mapping(uint256 => RoyaltyInfo) private _royaltyInfos;

  struct Artist {
    address wallet;
    uint256 mintStartWindow;
    uint256 mintEndWindow;
  }

  mapping(uint256 => Artist) private _artists;

  mapping(address => uint256) private _artistIndexByWallet;

  uint256 public artistsAdded = 0;

  uint256 public artistsRemoved = 0;

  modifier onlyAdmin() {
    require(_msgSender() == admin, "EVADAO: only admin");
    _;
  }

  modifier onlyArtistDuringWindow() {
    (address wallet, uint256 mintStartWindow, uint256 mintEndWindow) = getArtistInfo(_msgSender());

    require(wallet != address(0), "EVADAO: not an artist");
    require(mintStartWindow <= block.timestamp, "EVADAO: window not yet open");
    require(mintEndWindow >= block.timestamp, "EVADAO: window has expired");

    _;
  }

  constructor(address _evaDQContract) ERC721("EVADAO", "EVA") {
    admin = _msgSender();
    evaDQ = IEVADQ(_evaDQContract);
  }

  function setAdmin(address _admin) external onlyAdmin {
    admin = _admin;
  }

  function getAdmin() external view returns (address) {
    return admin;
  }

  function getArtistsByTokenId(uint256 _tokenId) external view returns (address[] memory artists) {
    require(_exists(_tokenId), "EVADAO: token does not exist");
    return _artworks[_tokenId].artists;
  }

  function tokenURI(uint256 _tokenId) public view override returns (string memory tokenUri) {
    require(_exists(_tokenId), "EVADAO: token does not exist");
    return _artworks[_tokenId].tokenUri;
  }

  function gatedURI(uint256 _tokenId) external view returns (string memory gatedUri) {
    require(_msgSender() == ownerOf(_tokenId), "EVADAO: sorry this is a secret");
    require(_exists(_tokenId), "EVADAO: token does not exist");
    return _artworks[_tokenId].gatedUri;
  }

  function getArtists() external view returns (address[] memory artists) {
    artists = new address[](artistsAdded - artistsRemoved);
    uint256 count;
    for(uint256 i = 0; i < artistsAdded; i++){
      if(_artists[i].wallet != address(0)){
        artists[count++] = _artists[i].wallet;
      }
    }
  }

  function getArtistInfo(address _wallet) public view returns (address wallet, uint256 mintStartWindow, uint256 mintEndWindow) {
    uint256 i = _artistIndexByWallet[_wallet];
    if(_artists[i].wallet == _wallet){
      return (_wallet, _artists[i].mintStartWindow, _artists[i].mintEndWindow);
    }
  }

  function addArtist(address _wallet) external onlyAdmin {
    addArtistWithWindow(_wallet, 0, 0);
  }

  function addArtistWithWindow(address _wallet, uint256 _mintStartWindow, uint256 _mintEndWindow) public onlyAdmin {
    (address wallet,,) = getArtistInfo(_wallet);
    require(wallet == address(0), "EVADAO: already added");

    //return to same index if re-adding an artist
    if(_artistIndexByWallet[_wallet] != 0){
      _artists[_artistIndexByWallet[_wallet]] = Artist(_wallet, _mintStartWindow, _mintEndWindow);
    }else{
      _artistIndexByWallet[_wallet] = artistsAdded;
      _artists[_artistIndexByWallet[_wallet]] = Artist(_wallet, _mintStartWindow, _mintEndWindow);
      artistsAdded++;
    }
  }

  function updateArtistMintWindow(address _wallet, uint256 _mintStartWindow, uint256 _mintEndWindow) external onlyAdmin {
    (address wallet,,) = getArtistInfo(_wallet);
    require(wallet != address(0), "EVADAO: artist does not exist");
    _artists[_artistIndexByWallet[_wallet]].mintStartWindow = _mintStartWindow;
    _artists[_artistIndexByWallet[_wallet]].mintEndWindow = _mintEndWindow;
  }

  function removeArtist(address _wallet) external onlyAdmin {
    (address wallet,,) = getArtistInfo(_wallet);
    require(wallet != address(0), "EVADAO: artist does not exist");
    _artists[_artistIndexByWallet[_wallet]].wallet = address(0);
    artistsRemoved++;
  }

  function mint(address[] memory _artworkArtists, address _royaltyReceiver, uint256 _royaltyInBp, string memory _tokenUri) external onlyArtistDuringWindow {
    mintWithGatedUri(_artworkArtists, _royaltyReceiver, _royaltyInBp, _tokenUri, "");
  }

  function mintWithGatedUri(address[] memory _artworkArtists, address _royaltyReceiver, uint256 _royaltyInBp, string memory _tokenUri, string memory _gatedUri) public onlyArtistDuringWindow {
    uint256 tokenId = totalSupply();
    _artworks[tokenId] = Artwork(_artworkArtists, _tokenUri, _gatedUri, false);
    _royaltyInfos[tokenId] = RoyaltyInfo(_royaltyReceiver, _royaltyInBp);
    _safeMint(_msgSender(), tokenId);

    evaDQ.mint(_msgSender(), tokenId);
  }

  function setGatedUri(string memory _gatedUri, uint256 _tokenId) external {
    require(_exists(_tokenId), "EVADAO: token does not exist");
    require(!_artworks[_tokenId].gatedUriLocked, "EVADAO: gatedUri is locked");
    require(_isArtistOfTokenId(_msgSender(), _tokenId), "EVADAO: an artist can set");
    _artworks[_tokenId].gatedUri = _gatedUri;
  }


  function lockGatedUri(uint256 _tokenId) external {
    require(_exists(_tokenId), "EVADAO: token does not exist");
    require(_msgSender() == ownerOf(_tokenId) || _isArtistOfTokenId(_msgSender(), _tokenId), "EVADAO: only owner or an artist can lock");
    _artworks[_tokenId].gatedUriLocked = true;
  }

  function _isArtistOfTokenId(address _artist, uint256 _tokenId) internal view returns (bool isArtist) {
    for(uint256 i = 0; i < _artworks[_tokenId].artists.length; i++){
      if(_artist == _artworks[_tokenId].artists[i]){
        return true;
      }
    }
  }

  /**
   * @dev See {IERC2981-royaltyInfo}.
   */
  function royaltyInfo(uint256 tokenId, uint256 salePrice) public view virtual override returns (address receiver, uint256 royaltyAmount) {
    receiver = _royaltyInfos[tokenId].receiver;
    royaltyAmount = BasisPoints.mulByBp(salePrice, _royaltyInfos[tokenId].royaltyInBp);
  }

  function updateRoyaltyReceiver(address _receiver, uint256 _tokenId) external {
    require(_msgSender() == _royaltyInfos[_tokenId].receiver, "EVADAO: only current receiver can change receiver");
    _royaltyInfos[_tokenId].receiver = _receiver;
  }

  /**
   * @dev Requests safeTransferFrom() of `_tokenId` token by first
   * requesting approval be set by the owner of the delegate token
   * with `_terms` terms.
   * @param _to address to transfer the token to
   * @param _tokenId token to transfer
   * @param _terms terms of the delegate approval request
   * @param _data data
   */
  function requestSafeTransferFrom (
    address _to,
    uint256 _tokenId,
    bytes memory _terms,
    bytes calldata _data)
  external virtual {
    _requestApproval(_to, _tokenId, _terms, _data);
    safeTransferFrom(ownerOf(_tokenId), _to, _tokenId, _data);
  }

  /**
   * @dev Requests approval be set for `_to` address by the owner
   * of the delegate token with `_terms` terms.
   * @param _to address to transfer the token to
   * @param _tokenId token to transfer
   * @param _terms terms of the delegate approval request
   * @param _data data
   */
  function _requestApproval(address _to, uint256 _tokenId, bytes memory _terms, bytes calldata _data) internal virtual {
    (address delegateContract, uint256 delegateToken) = getDelegateToken(_tokenId);
    address delegate = IERC721(delegateContract).ownerOf(delegateToken);
    //require(IERC165(delegate).supportsInterface(type(IERC721Dispatcher)), "RQ: not a valid dispatcher");

    IERC721Dispatcher(delegate).requestApproval(_msgSender(), _to, address(this), _tokenId, _terms, _data);
  }
}

// File: /contracts/IERC721Dispatcher.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;


/**
 * @title IERC721Dispatcher
 * @dev Interface for an ERC721Delegable token dispatcher.
 * @author 0xAnimist (kanon.art)
 */
interface IERC721Dispatcher {

  /**
   * @dev Emitted when a delegate token has been deposited.
   */
  event Deposited(address indexed sourceTokenContract, uint256 indexed sourceTokenId, uint256 tokenId, address depositedBy, bytes[] terms, bytes data);

  /**
   * @dev Emitted when a delegate token has been withdrawn.
   */
  event Withdrawn(address indexed sourceTokenContract, uint256 indexed sourceTokenId, uint256 tokenId, address withdrawnBy, bytes data);

  /**
   * @dev Emitted when an approval request has been granted.
   */
  event ApprovalGranted(address indexed sourceTokenContract, uint256 indexed sourceTokenId, address indexed to, address payee, bytes terms, bytes data);

  /**
   * @dev Emitted when terms are set for a token.
   */
  event TermsSet(address indexed owner, bytes[] terms, uint256 tokenId, bytes data);

  /**
   * @dev Deposits an array of delegate tokens of their corresponding delegable Tokens
   * in exchange for sDQ receipt tokens.
   *
   * Requirements:
   *
   * - must be the owner of the delegate token
   *
   * Emits a {Deposited} event.
   */
  function deposit(address[] memory _ERC721DelegableContract, uint256[] memory _ERC721DelegableTokenId, bytes[][] memory _terms, bytes calldata _data) external returns (uint256[] memory tokenIds);

  /**
   * @dev Withdraws a staked delegate token in exchange for `_tokenId` sDQ token receipt.
   *
   * Emits a {Withdrawn} event.
   */
  function withdraw(uint256 _tokenId, bytes calldata _data) external;

  /**
   * @dev Sets the terms by which an approval request will be granted.
   *
   * Emits a {TermsSet} event.
   */
  function setTerms(bytes[] memory _terms, uint256 _tokenId, bytes calldata _data) external;

  /**
   * @dev Gets the terms by which an approval request will be granted.
   */
  function getTerms(uint256 _tokenId) external view returns (bytes[] memory terms);

  /**
   * @dev Gets array of methodIds served by the dispatcher.
   */
  function getServedMethodIds() external view returns (bytes4[] memory methodIds);

  /**
   * @dev Gets source ERC721Delegable token for a given `_tokenId` token.
   */
  function getDepositByTokenId(uint256 _tokenId) external view returns (address contractAddress, uint256 tokenId);

  /**
   * @dev Gets tokenId` token ID for a given source ERC721Delegable token.
   */
  function getTokenIdByDeposit(address _ERC721DelegableContract, uint256 _ERC721DelegableTokenId) external view returns (bool success, uint256 tokenId);

  /**
   * @dev Requests dispatcher call approveByDelegate() on the source ERC721Delegable
   * token corresponding to `_tokenId` token for `_to` address with `_terms` terms.
   */
  function requestApproval(address _payee, address _to, address _ERC721DelegableContract, uint256 _ERC721DelegableTokenId, bytes memory _terms, bytes calldata _data) external payable;

  /**
   * @dev Withdraws fees accrued to all eligible recipients for `_tokenId` token without withdrawing the token itself.
   *
   * Requirements:
   *
   * - token must exist.
   *
   */
  function claimFeesAccrued(uint256 _tokenId) external returns (bool success, address currency);
}

// File: /contracts/IERC721Delegable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC721/IERC721.sol";

/**
 * @title IERC721Delegable
 * @dev Interface for a delegable ERC721 token contract
 * @author 0xAnimist (kanon.art)
 */
interface IERC721Delegable is IERC721 {
  /**
   * @dev Emitted when the delegate token is set for `tokenId` token.
   */
  event DelegateTokenSet(address indexed delegateContract, uint256 indexed delegateTokenId, uint256 indexed tokenId, address operator, bytes data);

  /**
   * @dev Sets the delegate NFT for `tokenId` token.
   *
   * Requirements:
   *
   * - `tokenId` must exist.
   *
   * Emits a {DelegateTokenSet} event.
   */
  function setDelegateToken(address _delegateContract, uint256 _delegateTokenId, uint256 _tokenId) external;

  /**
   * @dev Sets the delegate NFT for `tokenId` token.
   *
   * Requirements:
   *
   * - `tokenId` must exist.
   *
   * Emits a {DelegateTokenSet} event.
   */
  function setDelegateToken(address _delegateContract, uint256 _delegateTokenId, uint256 _tokenId, bytes calldata _data) external;

  /**
   * @dev Gets the delegate NFT for `tokenId` token.
   *
   * Requirements:
   *
   * - `tokenId` must exist.
   */
  function getDelegateToken(uint256 _tokenId) external view returns (address contractAddress, uint256 tokenId);

  /**
   * @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 delegate token.
   * - `tokenId` must exist.
   *
   * Emits an {Approval} event.
   */
  function approveByDelegate(address to, uint256 tokenId) external;
}

// File: /contracts/ERC721EnumerableDelegable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "./ERC721Delegable.sol";

/**
 * @title ERC721EnumerableDelegable
 * @dev Required interface of an ERC721RQ compliant contract.
 * @author 0xAnimist (kanon.art)
 */
abstract contract ERC721EnumerableDelegable is ERC721Enumerable, ERC721Delegable {

  /**
   * @dev See {IERC165-supportsInterface}.
   */
  function supportsInterface(bytes4 interfaceId) public view virtual override(ERC721Delegable, ERC721Enumerable) returns (bool) {
      return
        interfaceId == type(IERC721Delegable).interfaceId
        || interfaceId == type(IERC721Enumerable).interfaceId//TODO: REMOVE?
        || super.supportsInterface(interfaceId);
  }


  /**
   * @dev Hook that is called before any token transfer. This includes minting
   * and burning.
   *
   * Calling conditions:
   *
   * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
   * transferred to `to`.
   * - When `from` is zero, `tokenId` will be minted for `to`.
   * - When `to` is zero, ``from``'s `tokenId` will be burned.
   * - `from` cannot be the zero address.
   * - `to` cannot be the zero address.
   *
   * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
   */
  function _beforeTokenTransfer(
      address from,
      address to,
      uint256 tokenId
  ) internal virtual override(ERC721, ERC721Enumerable) {
      super._beforeTokenTransfer(from, to, tokenId);
  }

  function _burn(uint256 tokenId) internal virtual override(ERC721, ERC721Delegable) {
    super._burn(tokenId);
  }

}

// File: /contracts/ERC721Delegable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IERC721Delegable.sol";
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";

/**
 * @title ERC721Delegable
 * @dev Implementation of the IERC721Delegable interface, extending the
 * {ERC721} non-fungible token standard with the addition of a delegate token.
 * @author 0xAnimist (kanon.art)
 */
abstract contract ERC721Delegable is ERC721, IERC721Delegable {

  struct Delegate {
    address contractAddress;
    uint256 tokenId;
  }

  // Mapping token ID to delegate token
  mapping(uint256 => Delegate) private _delegates;

  /**
   * @dev See {IERC165-supportsInterface}.
   */
  function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
      return
        interfaceId == type(IERC721Delegable).interfaceId
        || super.supportsInterface(interfaceId);
  }

  /**
   * @dev See {IERC721Delegable-setDelegateToken}.
   */
  function setDelegateToken(address _delegateContract, uint256 _delegateTokenId, uint256 _tokenId) public virtual override {
    setDelegateToken(_delegateContract, _delegateTokenId, _tokenId, "");
  }

  /**
   * @dev See {IERC721Delegable-setDelegateToken}.
   */
  function setDelegateToken(address _delegateContract, uint256 _delegateTokenId, uint256 _tokenId, bytes memory _data) public virtual override {
    require(_isDelegateOrOwnerOfUndelegated(_msgSender(), _tokenId), "ERC721Q: not authorized to set delegate");

    _delegates[_tokenId] = Delegate(_delegateContract, _delegateTokenId);

    emit DelegateTokenSet(_delegateContract, _delegateTokenId, _tokenId, _msgSender(), _data);
  }

  /**
   * @dev See {IERC721Delegable-getDelegateToken}.
   */
  function getDelegateToken(uint256 _tokenId) public view virtual override returns (address contractAddress, uint256 tokenId) {
    return (_delegates[_tokenId].contractAddress, _delegates[_tokenId].tokenId);
  }

  /**
   * @dev See {IERC721Delegable-approveByDelegate}.
   */
  function approveByDelegate(address to, uint256 tokenId) public virtual override {
      address owner = ERC721.ownerOf(tokenId);
      require(to != owner, "ERC721: approval to current owner");

      require(_msgSender() == _getDelegateOwner(tokenId),"ERC721: approve caller is not owner nor approved for all nor delegate");

      _approve(to, tokenId);
  }

  /**
   * @dev Returns true if `_operator` is the owner of the delegate token of `_tokenId
   * token or, if and only if the delegate token has not been set (ie. is address(0)),
   * returns true if `_operator` is the owner of `_tokenId` token.
   */
  function _isDelegateOrOwnerOfUndelegated(address _operator, uint256 _tokenId) internal view virtual returns (bool) {
    address delegate = _getDelegateOwner(_tokenId);
    if(delegate != address(0)){//delegate has been set
      return _operator == delegate;
    }else{//delegate has not been set
      return _operator == ownerOf(_tokenId);
    }
  }

  /**
   * @dev Returns owner of the delegate token for `_tokenId` token, or address(0) if
   * no delegate token has been set.
   *
   * Requirements:
   *
   * - tokenId must exist
   */
  function _getDelegateOwner(uint256 _tokenId) internal view returns (address delegateOwner) {
    require(_exists(_tokenId), "ERC721Q: token does not exist");

    if(_delegates[_tokenId].contractAddress != address(0)){//delegate has been set
      return IERC721(_delegates[_tokenId].contractAddress).ownerOf(_delegates[_tokenId].tokenId);//fails if delegate token has been burnt
    }

    return address(0);//delegate has not been set
  }

  /**
   * @dev Burns `tokenId`. See {ERC721-_burn}.
   *
   * Requirements:
   *
   * - The caller must own `tokenId` or be an approved operator.
   */
  function _burn(uint256 tokenId) internal virtual override {
    setDelegateToken(address(0),0,tokenId);
    ERC721._burn(tokenId);
  }
}

// File: /contracts/BasisPoints.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @title BasisPoints
/// @notice Provides a function for multiplying in basis points
library BasisPoints {

  uint128 public constant BASE = 10000;

  /**  @notice Calculate _input * _basisPoints / _base rounding down
    *  @dev from Mikhail Vladimirov's response here: https://ethereum.stackexchange.com/questions/55701/how-to-do-solidity-percentage-calculation/55702
    */
  function mulByBp(uint256 _input, uint256 _basisPoints) public pure returns (uint256) {
    uint256 a = _input / BASE;
    uint256 b = _input % BASE;
    uint256 c = _basisPoints / BASE;
    uint256 d = _basisPoints % BASE;

    return a * c * BASE + a * d + b * c + b * d / BASE;
  }

}

// File: @openzeppelin/contracts/utils/introspection/IERC165.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// File: @openzeppelin/contracts/utils/introspection/ERC165.sol



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

pragma solidity ^0.8.0;

import "./IERC165.sol";

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

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



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

pragma solidity ^0.8.0;

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

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

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

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

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

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



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

pragma solidity ^0.8.0;

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

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library 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

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

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



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

pragma solidity ^0.8.0;

import "../IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Metadata is IERC721 {
    /**
     * @dev Returns the token collection name.
     */
    function name() external view returns (string memory);

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

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

// File: @openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol



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

pragma solidity ^0.8.0;

import "../IERC721.sol";

/**
 * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
 * @dev See https://eips.ethereum.org/EIPS/eip-721
 */
interface IERC721Enumerable is IERC721 {
    /**
     * @dev Returns the total amount of tokens stored by the contract.
     */
    function totalSupply() external view returns (uint256);

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

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

// File: @openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/ERC721Enumerable.sol)

pragma solidity ^0.8.0;

import "../ERC721.sol";
import "./IERC721Enumerable.sol";

/**
 * @dev This implements an optional extension of {ERC721} defined in the EIP that adds
 * enumerability of all the token ids in the contract as well as all token ids owned by each
 * account.
 */
abstract contract ERC721Enumerable is ERC721, IERC721Enumerable {
    // Mapping from owner to list of owned token IDs
    mapping(address => mapping(uint256 => uint256)) private _ownedTokens;

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

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

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

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC721) returns (bool) {
        return interfaceId == type(IERC721Enumerable).interfaceId || super.supportsInterface(interfaceId);
    }

    /**
     * @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
     */
    function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual override returns (uint256) {
        require(index < ERC721.balanceOf(owner), "ERC721Enumerable: owner index out of bounds");
        return _ownedTokens[owner][index];
    }

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

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

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

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

    /**
     * @dev Private function to add a token to this extension's ownership-tracking data structures.
     * @param to address representing the new owner of the given token ID
     * @param tokenId uint256 ID of the token to be added to the tokens list of the given address
     */
    function _addTokenToOwnerEnumeration(address to, uint256 tokenId) private {
        uint256 length = ERC721.balanceOf(to);
        _ownedTokens[to][length] = tokenId;
        _ownedTokensIndex[tokenId] = length;
    }

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

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

        uint256 lastTokenIndex = ERC721.balanceOf(from) - 1;
        uint256 tokenIndex = _ownedTokensIndex[tokenId];

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

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

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

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

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

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

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

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

// File: @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721Receiver.sol)

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface 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 `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

// File: @openzeppelin/contracts/token/ERC721/IERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

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

/**
 * @dev Required interface of an ERC721 compliant contract.
 */
interface IERC721 is IERC165 {
    /**
     * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
     */
    event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);

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

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

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

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

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, 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/token/ERC721/ERC721.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC721/ERC721.sol)

pragma solidity ^0.8.0;

import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/Strings.sol";
import "../../utils/introspection/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 ERC721 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) private _owners;

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

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

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

    /**
     * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
     */
    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: balance query for the zero address");
        return _balances[owner];
    }

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

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

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

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

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

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

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

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

        _approve(to, tokenId);
    }

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

        return _tokenApprovals[tokenId];
    }

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

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

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

        _transfer(from, to, tokenId);
    }

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

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

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

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

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

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

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

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

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

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

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

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

    /**
     * @dev Destroys `tokenId`.
     * The approval is cleared when the token is burned.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     *
     * Emits a {Transfer} event.
     */
    function _burn(uint256 tokenId) internal virtual {
        address owner = ERC721.ownerOf(tokenId);

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

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

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

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

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

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

        _beforeTokenTransfer(from, to, tokenId);

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

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

        emit Transfer(from, to, tokenId);

        _afterTokenTransfer(from, to, tokenId);
    }

    /**
     * @dev Approve `to` to operate on `tokenId`
     *
     * Emits a {Approval} event.
     */
    function _approve(address to, uint256 tokenId) internal virtual {
        _tokenApprovals[tokenId] = to;
        emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
    }

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

    /**
     * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
     * The call is not executed if the target address is not a contract.
     *
     * @param from address representing the previous owner of the given token ID
     * @param to target address that will receive the tokens
     * @param tokenId uint256 ID of the token to be transferred
     * @param _data bytes optional data to send along with the call
     * @return bool whether the call correctly returned the expected magic value
     */
    function _checkOnERC721Received(
        address from,
        address to,
        uint256 tokenId,
        bytes memory _data
    ) private returns (bool) {
        if (to.isContract()) {
            try 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 {
                    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: @openzeppelin/contracts/interfaces/IERC2981.sol



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

pragma solidity ^0.8.0;

import "./IERC165.sol";

/**
 * @dev Interface for the NFT Royalty Standard.
 *
 * A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal
 * support for royalty payments across all NFT marketplaces and ecosystem participants.
 *
 * _Available since v4.5._
 */
interface IERC2981 is IERC165 {
    /**
     * @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of
     * exchange. The royalty amount is denominated and should be payed in that same unit of exchange.
     */
    function royaltyInfo(uint256 tokenId, uint256 salePrice)
        external
        view
        returns (address receiver, uint256 royaltyAmount);
}

// File: @openzeppelin/contracts/interfaces/IERC165.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC165.sol)

pragma solidity ^0.8.0;

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