// File: contracts/loveletters_V2.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.0;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import 'base64-sol/base64.sol';


interface DamienInterface{
  function getDamien() external view returns (string memory);
}

contract LoveLetters is Ownable, ERC721Enumerable {

    DamienInterface private _damienContract;

    using Counters for Counters.Counter;
    //Relevant mappings
    Counters.Counter private _tokenIdTracker;
    // initilization inputs
    uint256 private _price;
    uint256 public maxSupply;


    mapping(uint256 => string) private tokenIdToLetter;
    mapping(uint256 => string) private tokenIdToSenderName;
    mapping(uint256 => string) private tokenIdToRecipientName;

    address public constant staffVaultAddress =
        0x8Cd4af5786685a458e7A16CF456887364eB6277d;

    event LetterWritten(
        uint256 letterid,
        address author_address,
        address to_address,
        string author_name,
        string recipient_name,
        string content
    );

    function toString(uint256 value) internal pure returns (string memory) {
    // Inspired by OraclizeAPI's implementation - MIT license
    // 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);
    }

    //Constructor
    constructor(
        string memory name_,
        string memory symbol_,
        uint256 maxSupply_,
        uint256 price_,
        address damienAddress_
    ) ERC721(name_, symbol_) {
        maxSupply = maxSupply_;
        _price = price_;
        _damienContract = DamienInterface(damienAddress_);
         _tokenIdTracker.increment();
    }

    function mint(address to) internal {
        _safeMint(to, _tokenIdTracker.current());
        _tokenIdTracker.increment();
    }

    function writeLetter(
        string memory letter,
        address to,
        string memory recipientName,
        string memory senderName
    ) public payable {
        require(to != msg.sender);
        require(msg.value >= _price);
        require(totalSupply() + 1 <= maxSupply);
        tokenIdToLetter[_tokenIdTracker.current()] = letter;
        tokenIdToRecipientName[_tokenIdTracker.current()] = recipientName;
        tokenIdToSenderName[_tokenIdTracker.current()] = senderName;
        mint(to);

        emit LetterWritten(
            _tokenIdTracker.current() - 1,
            msg.sender,
            to,
            senderName,
            recipientName,
            letter
        );
    }


    function readLetter(uint256 tokenId) public view returns (string memory) {
        return string(tokenIdToLetter[tokenId]);
    }

    function withdrawAll() public payable onlyOwner {
        uint256 balance = address(this).balance;
        payable(staffVaultAddress).transfer(balance);
    }


    //tokenURI function
    function tokenURI(uint256 tokenId)
        public
        view
        override
        returns (string memory)
    {
        string[11] memory parts;
        parts[
            0
        ] = '<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 256 239" preserveAspectRatio="xMinYMin meet" fill="none" xmlns:v="https://vecta.io/nano"><defs><style>@font-face{font-family:"Damion";src:url(';


        parts[1] = _damienContract.getDamien();

        parts[2] = ') format("woff"); font-weight:normal;font-style:normal;}</style></defs><style><![CDATA[.B,.d{font-family:Damion}.C{fill:#3116da}.D,.d{font-size:12px}]]></style><path d="M256 0H0V239H256V0Z" fill="#000"/><path d="M192.4.3c-1 .4-1.7 1-2.4 2.6-.6 1.3-1.3 2.2-2 2.5-.3.1-1.7.3-3.2.4l-2.7.1-.8-.5c-1-.7-1.6-1.5-2-3-.2-.6-.6-1-.8-1.2-.2-.1-1 0-1.8.1-1.7.3-3 1-3 1.8 0 1.5-2.4 3-5 3-1.6 0-2.8-.3-6.6-1.6l-4-1.3c-.4-.1-.8.1-1.5 1-1.3 1.2-2.8 1.8-4.7 1.8-2.3 0-4.3-1-5.2-2.3-.5-.7-1.7-1.2-3-1.2-1.4 0-2 .3-3.2 1.7-1.4 1.5-2.3 2-4.5 2-1.3 0-2-.1-2.8-.4-1.4-.6-2.8-2-2.8-2.6 0-.8-1-1.5-2.3-1.5-.6 0-1.5.1-2 .2-1 .2-1 .3-1.3 1.3-.5 1.3-1.2 2-2.5 2.5-3 1.2-7 .3-8-1.8l-.7-1c-.3-.3-2-.3-3.4 0-1 .2-1.3.3-2 1.3-1.3 1.5-2 1.8-4.6 1.8-2.5 0-3.4-.3-4.8-1.6-.7-.7-1-1-2.2-1.2-1-.3-1.5-.2-2.6 0-.8.2-1.5.5-1.7.7-.6.7-3 1.8-4 2-1.4.2-3.5-.1-4.5-.7-.4-.2-1-1-1.4-1.6C81.4 2 81 1.8 80 2.6c-.4.3-1.5.7-2.3 1s-2 .6-2.7 1c-2.4 1-4.8 1.2-6.6.8-1.2-.3-2.5-1-2.5-1.4 0-.7-1-1.5-2.2-2-2-.7-4.2-.1-4.2 1 0 .6-1.4 1.7-2.7 2-2 .6-4.5.4-6-.6-.3-.2-1-.7-1.2-1-.8-1-2-1.4-3.5-1.4-1.6 0-2 .2-3.2 1.6-.4.5-1.2 1-1.7 1.3-.8.4-1 .4-2.8.3-4-.2-4.5-.5-5-2-.6-1.6-.8-1.7-2.6-1.7-2.2 0-3 .4-4.5 2-.7.8-1.5 1.4-2 1.6-1 .4-3.2.5-4.7.1C18 4.8 16 3.4 16 3c0-.5-1-.8-3-.8-2 0-2.4.1-2.4.7 0 .8-4.5 3.5-6 3.5-.2 0-.8-.2-1.2-.4s-1-.4-1-.4c-.1 0-.6.4-1 1C1 7.2 1 7.7.7 9.2c-.1 1.2 0 2 .2 2.2.2.3 1.2.8 2.3 1.3 1.3.5 2.2 1 2.5 1.5.6.8 1 3.2.4 4-.2.2-1.4 1-2.7 1.8C1.2 21 1 21.2 1 22c-.2 1 .3 2.3 1 2.5.3.1 1.2.4 2 .8 2 1 2.6 2 2.6 4 0 1.7-.4 2.2-2.8 3.4-1.8 1-2.2 1.4-2.2 3 0 .7.1 1 .7 1.2.4.2.8.4 1 .4.7 0 2 .7 2.5 1.4.7 1 1 2.7.6 3.6-.4 1-2.3 2.5-3.8 2.8-1 .2-1.2.4-1.7 1.3-.3.6-.6 1.4-.7 1.8L0 49h1.5c2 0 3.5.5 4.3 1.6C7 52 6.4 54 4.2 56c-1.8 1.6-2.2 2.2-2.5 3.2-.3 1 0 1.8 1 2 2.2.6 3 1 3.4 1.5.7 1 1 2 .4 3.2-.5 1.3-.6 1.3-2.5 3-1.6 1.2-2 2-1.7 3 .2.8 1 1.4 2 1.6 1.2.3 1.8 1 2 2.3.3 2-1 3.2-3 3.2-2.6 0-3 .7-2 3.3 1 2.3 1 2.6 2 2.8 1 .2 2 1 2.6 2 1.4 2.2-.1 4.8-3 5.4-2.7.5-3 1-1.7 2.7.7 1 1 1.4 2.4 2 2 1 2.3 1.3 2.6 2 1 2.3-.3 4.5-3 5.7-1 .5-1.8 1.4-1.8 2.4 0 1 .5 1.3 2 2 3.7 1.4 4 4 1 6-1 .6-1.3 1-1.7 2-1 2.4-.5 3.7 2 4.5 1 .3 1.7 1.4 1.8 3 .1 1 0 1.3-.7 2.2-.6.7-1 1-2 1.5-2 .7-2.3 1-2.3 2.4s.6 2 2.4 2.8c2 1 3 2.2 2.8 3.8-.1.5-.3 1.2-.6 1.5-.6.8-2.3 2-3.4 2.6-1.2.5-1.3.7-1.3 1.5 0 .7.4 1 3.2 3 1.8 1 2.3 3.5 1.2 5.3-.5.7-1.3 1-2.4 1-1 0-1.5.4-1.7 1.6l-.3 2c-.1.8.1 1 1.2 1.3 1.7.3 3.2 2 3.4 3.7.2 1.6-.2 2.3-2 3.2-1.8 1-2 1.4-2.6 3.2-.4 1.4-.2 2 .5 1.8.6-.2 2.7.8 3.6 1.8.5.5.6.8.6 2 0 .7-.1 1.6-.3 1.8-.2.3-1 1-2 1.7-1.8 1.3-3 2.6-3.2 3.8-.2.7.1 1 1.6 1.2 1 .2 2.6 1.2 3 2 .6 1 1 2.5.6 3.4-.4 1-1.8 2-3.5 2.4-1.2.3-1.5.4-1.8 1-.7 1.2.2 2.5 2 3 1.8.6 2.8 1.4 3.3 2.5.8 2-.6 4.4-3 4.8-2.4.4-3 1.4-2.3 3.2.4 1 .6 1 2 1.8 2 1 3 1.6 3.4 2.3.5.7.5 2.6-.1 3.5-.4.7-1 1-3.7 1.7-1.2.3-1.4.5-1.6 1.8-.2 1.6.1 2 2.4 3 2.5 1 3 1.8 3 4 0 1.8-.2 2-2.3 3.2-1.7 1-2.6 1.8-3 2.7-.3 1 0 1.2 1.7 1.7 1.5.4 3.4 1.6 3.4 2.2 0 .1.6 1 1.4 1.6a9 9 0 0 1 1.6 1.8c.3.7.8 1 2 1.4 1.6.4 2.3.2 4-1.7 2.2-2 2.4-2.3 4.3-2.4 2.5-.2 3.2.3 4 3 .3 1 .5 1 1 1.3 1 .3 4 .2 5-.2.4-.1 1.3-1 2-1.6 2.2-2.2 2.6-2.4 5-2.4 2 0 2.2 0 3 .5 1 .7 2.3 2.2 2.4 3.3.2 1 .8 1.3 2.4 1.2 1.5-.2 2.4-1 3.5-2.6 1-1.4 1-1.6 2-2 1.2-.4 2-.5 3.8-.2 2.3.4 3.7 1.3 4 3 .2.7.6 1 1.6 1.4 1.2.4 2.3.6 3.4.3 1-.2 1-.3 1.4-1.8.2-1 1.4-2.4 2.4-2.6.4-.1 1.5-.2 2.5-.3 1.4-.1 2 0 2.8.2 1.5.5 1.8.8 2.4 2.3l.5 1.3h1c2.3 0 3.2-.3 4.8-1.8 1.7-1.5 2.8-2 4.2-2.3 1.8-.2 2.6 0 4.5 1.4 2 1.4 3.3 2 5 2.2 1.3.2 1.5.1 2-1 .7-1.5 3-2.6 5.7-2.6 2.3 0 4.5 1 4.5 2 0 .7.6 1.8 1.2 2 .7.3 2 .3 3 0a16 16 0 0 0 4.3-3.3c1-.8 4.3-1 5.4-.1.3.2 1 .8 1.4 1.5 1 1.2 1 1.2 2.3 1.4.8.1 2 .1 2.5.1 1.2-.1 1.6-.4 3.4-2 1.5-1.5 3.2-1.8 5.6-1.3 1 .2 1.3.5 2 1.2 1.8 2 4 3 6 2.4 1-.3 1.2-.4 2-2 .5-1 2.2-1.6 4-1.8 2.8-.2 5.2.8 5.5 2.3.1.4.3 1 .4 1a15 15 0 0 0 2.1.6c1 .2 1.8.5 1.8.6s.3.2.6.1c.5-.1.6-.2.7-1 .3-2 2.8-3.6 5.5-3.6 1.8 0 2.4.3 3 1.6.8 2 2.7 3 5.4 3 1.8 0 2-.2 2.3-1 .5-2 4.2-4 7-3.7 1.2.1 3 1.5 3.6 2.6.3.5.8 1 1.3 1.2 1.8.8 3.5 1.3 4 1.3.2-.1.4-.5.5-1 .3-1.8 1.7-3.2 3.6-3.6 1.2-.2 3.8-.2 4.5 0 1 .4 2.3 1.4 3 2.4.7 1 1.6 1.5 3.6 1.7 1.3.1 1.3.1 2.4-2 .5-1 2-2 3.3-2.3 2-.5 5 .2 5.8 1.4.2.3.4 1 .5 1.8.2 1.4 1 2.3 2 2.7 1.4.5 1.7.4 3-1.6 1.5-2 3.6-4 5-4.2 1-.2 4.3.2 5 .5.2.1.7.8 1 1.4 1 1.5 1.8 2.2 3.2 2.6 1.3.4 2.2.3 2.6-.3 2-3 2-3.2 3.2-3.8 1.6-.7 3.5-.7 5.4 0 1.8.7 2.4.6 2.4-.4 0-1-.8-2-2.2-2.8-1-.6-1.3-.8-1.8-2-.5-1.4-.6-1.5-.2-2.4.5-1.3 1.4-2 3.7-2.5l2-.5v-1c.1-1.4-.2-1.8-2.4-3.2-2-1.3-2.8-2-3-3-.2-1 .2-2 1-2.7.3-.2 1.4-.7 2.8-1 2.7-.7 2.8-1 1.7-2.7-.7-1-1-1.3-2.6-2.2-1.2-.7-2-1.3-2.4-1.8-.6-1-.8-2.3-.4-3.3.3-1 1.7-1.8 3-2 2.6-.5 2.5-.4 2.4-1.8-.1-.7-.2-1.6-.2-2 0-.8-.1-1-2.4-2.6l-2.4-1.7V190c0-1.4 0-1.4 1-2 1-.7 2.5-1 4.5-1 1.6 0 1.8-.2 1-1-.2-.2-.4-.7-.4-1 0-1-1-2-2.2-2.3-3-.7-4.4-2-4.4-4 0-2 1.5-3.3 4.3-3.5 1.7-.1 2-.4 2-1-.3-1-1.5-2.7-1.8-2.7-.5 0-3-2-3.4-2.7-.2-.4-.5-1.5-.5-2.5-.1-2-.1-2 2.7-2.8 1.8-.4 2-.6 2.3-2 .3-1.7-.7-3-3.4-4-1-.4-1.3-.6-1.7-1.2-.8-1.5-.4-2.7 1.7-4.5 1.4-1 2-2.5 1.8-3.7-.1-.6-.5-1-1.5-2-2.6-2.2-3.2-3.5-2-5.2.6-1 1.7-1.4 4-1.7 2.4-.4 2.5-.4 2.3-3-.1-1.7-.3-2.3-.6-2.5-.2-.1-1-.2-2-.2-1.3 0-1.6-.1-2.2-.5-2-1.5-2-4-.1-5.6.3-.2 1-.6 1.8-.7 1.4-.3 1.7-.7 1.7-1.7 0-1.3-.8-2.4-2.2-3-2-.8-2.5-1.3-2.7-2.5-.2-1.3.2-2.5 1-3.2.7-.5 3-1.4 3.8-1.4s1-1 .8-2.5a3 3 0 0 0-2.6-2.4c-2.8-.6-4-3-2.5-5.2.8-1.2 1.4-1.5 3.3-1.6.8-.1 1.6-.2 1.8-.4.6-.3.8-1.6.3-2.7-.4-.8-.8-1.2-2.6-2.3-1.2-.8-2.3-1.6-2.5-1.8-.3-.3-.4-1-.4-2 0-1.3.1-1.6.5-2 .3-.2.5-.3.6-.2.3.2 2-.1 2.8-.7 1.4-1 1.7-2.7.7-4-.2-.3-1-.7-2.2-1-2.3-.8-2.6-1.2-2.7-3.4-.1-2 1-3.6 2.5-3.6 1 0 2.3-.6 2.6-1.3.5-1 0-2-1.2-3-.6-.5-1.5-1-2-1.2-1-.3-1.8-1.3-2.2-2.8-.6-2 .4-3.3 3-4 2-.5 3-1.6 3-3 0-.7-1-1.3-3-2.2-2-.8-2.7-1.6-2.7-3.5 0-1.2.1-1.5.8-2.2.7-.8 1-1 2.3-1.2 2-.4 3-1 3-1.7 0-.4-.2-1-.4-1.6-.5-1-.6-1-3-1.8-1.6-.5-2-1-2.3-3-.2-1.4-.2-1.7.2-2.5.3-.5.8-1 1.2-1.5.7-.6 1-.6 2-.6 2 0 2.2-.1 2-2.4-.2-1.7-.3-2-.8-2.3-.3-.2-1-.4-1.2-.4-2.3 0-4-2.3-3.4-4.6.4-1.3 1-1.7 3-2.3 2.8-.7 3-1 2.3-2.7-.4-1-.8-1.2-3.7-3l-1-.8v-2c-.1-2-.1-2 .5-2.5.3-.3 1.4-.8 2.4-1.2 2.2-1 3-1.7 2.4-2.8-.3-.7-.6-1-3.6-2.2-1.2-.5-2-1.8-2.2-3.2-.1-1 0-1.3.7-2.4l.8-1.2-.8-.2c-.4-.1-1.3-.3-2-.4-1.3-.1-1.7-.3-3.5-2-1.5-1.4-2.6-1.8-4.3-1.6-1 .1-2.2 1-2.2 1.8 0 .6-1.2 1.4-2.7 1.8-1.6.3-2.3.3-4 0-1.7-.4-3-1.2-3.4-2.2-.3-1-1-1-3-1-2 0-2.7.2-3 1-.5 1.4-1.5 2-3.8 2.5-2.7.4-5.3-.4-6.2-2-1-1.6-1.6-1.8-4-1-1 .3-1.8.7-3 1.7-1.5 1-2 1.3-3 1.4-1.4.1-3 0-4-.4-1.4-.6-3-3-2.7-4 .1-.3 0-.7-.2-1-.4-.6-1.5-.7-2.8-.2z" fill="#fff"/><text xml:space="preserve" style="white-space:pre" letter-spacing="0em" class="B C D"><tspan x="18" y="58.9">Dear  </tspan></text><text fill="#000" xml:space="preserve" style="white-space:pre" letter-spacing="0em" class="B D"><tspan x="46.7" y="58.9">';

        parts[3] = tokenIdToRecipientName[tokenId];

        parts[
            4
        ] = ',</tspan></text><text xml:space="preserve" style="white-space:pre" letter-spacing="0em" class="B C D"><tspan x="18" y="200.9">Love,</tspan></text><text fill="#000" xml:space="preserve" style="white-space:pre" letter-spacing="0em" class="B D"><tspan x="18" y="216.9">';

        parts[5] = tokenIdToSenderName[tokenId];

        parts[
            6
        ] = '</tspan></text><path d="M19 22.6l5.6-3.7 5 3.7-3.2 3-7.4-3z" fill="#e4a649"/><path d="M43 23.2L36.2 19l-2 6.7 8.6-2.5z" fill="#b5f42e"/><path d="M19 31.4L36.2 19l-3 12.5H19z" fill="#e6f15f"/><path d="M19 30.5v-7.7l7.7 2.7-7.7 5z" fill="#bb3030"/><path d="M30.3 40L19 31.4h8.6l2.7 8.7z" fill="#801ecd"/><path d="M43 31.4H28.5L31 40 43 31.4z" class="C"/><path d="M33.3 31.4l1.7-6 8-2.7v8.6h-9.6z" fill="#42da51"/><path d="M36 18l-5.6 4-5.6-4-7 4.4v8.7L30.5 41 43 31.2v-8.7L36 18zm-11 7.7l-5.8 4v-6l5.8 2zm5.3-2l4.6-3.3-2.6 9.8H20.7l9.7-6.6h0zm6-3.8l4.3 2.8-5.5 2 1.2-4.7zm-9 11.7l2 6.8-8.6-6.8h6.8zm1.4 0h11.6L30.8 39l-2-7.5zm12.8-1.4h-7.8l1-4 6.7-2.3v6.4zm-12.3-7.4l-2.8 2-6.3-2 4.6-3 4.5 3.2z" fill="#000"/><text xml:space="preserve" style="white-space:pre" font-size="24" letter-spacing="0em" class="B C"><tspan x="50" y="36.2">#';

        parts[7] = toString(tokenId);

        parts[
            8
        ] = '</tspan></text><foreignObject class="d" x="18" y="68.9" width="220px" height="110px"><div xmlns="http://www.w3.org/1999/xhtml" style="text-overflow: ellipsis; display: -webkit-box; color: rgba(0,0,0,0.7); -webkit-line-clamp: 6; -webkit-box-orient: vertical">I love you because ';

        parts[9] = tokenIdToLetter[tokenId];

        parts[
            10
        ] = '</div></foreignObject><path d="M218 18h24v24h-24zm0 179h24v24h-24z" class="C"/></svg>';
        string memory output = string(
            abi.encodePacked(
                parts[0],
                parts[1],
                parts[2],
                parts[3],
                parts[4],
                parts[5],
                parts[6],
                parts[7],
                parts[8]
            )
        );
        output = string(abi.encodePacked(output, parts[9], parts[10]));


        string memory json = Base64.encode(
            bytes(
                string(
                    abi.encodePacked(
                        '{"name": "Letter #',
                        toString(tokenId),
                        '", "description": "On-chain Letters of Love", "image": "data:image/svg+xml;base64,',
                        Base64.encode(bytes(output)),
                        '"}'
                    )
                )
            )
        );
        output = string(
            abi.encodePacked("data:application/json;base64,", json)
        );

        return output;
    }



  }

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/Context.sol";

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

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

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

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

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

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

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

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



// SPDX-License-Identifier: MIT

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/utils/Counters.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @title Counters
 * @author Matt Condon (@shrugs)
 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
 * of elements in a mapping, issuing ERC721 ids, or counting request ids.
 *
 * Include with `using Counters for Counters.Counter;`
 */
library Counters {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }

    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }

    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }

    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }

    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}

// File: base64-sol/base64.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0;

/// @title Base64
/// @author Brecht Devos - <brecht@loopring.org>
/// @notice Provides functions for encoding/decoding base64
library Base64 {
    string internal constant TABLE_ENCODE = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
    bytes  internal constant TABLE_DECODE = hex"0000000000000000000000000000000000000000000000000000000000000000"
                                            hex"00000000000000000000003e0000003f3435363738393a3b3c3d000000000000"
                                            hex"00000102030405060708090a0b0c0d0e0f101112131415161718190000000000"
                                            hex"001a1b1c1d1e1f202122232425262728292a2b2c2d2e2f303132330000000000";

    function encode(bytes memory data) internal pure returns (string memory) {
        if (data.length == 0) return '';

        // load the table into memory
        string memory table = TABLE_ENCODE;

        // multiply by 4/3 rounded up
        uint256 encodedLen = 4 * ((data.length + 2) / 3);

        // add some extra buffer at the end required for the writing
        string memory result = new string(encodedLen + 32);

        assembly {
            // set the actual output length
            mstore(result, encodedLen)

            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            // run over the input, 3 bytes at a time
            for {} lt(dataPtr, endPtr) {}
            {
                // read 3 bytes
                dataPtr := add(dataPtr, 3)
                let input := mload(dataPtr)

                // write 4 characters
                mstore8(resultPtr, mload(add(tablePtr, and(shr(18, input), 0x3F))))
                resultPtr := add(resultPtr, 1)
                mstore8(resultPtr, mload(add(tablePtr, and(shr(12, input), 0x3F))))
                resultPtr := add(resultPtr, 1)
                mstore8(resultPtr, mload(add(tablePtr, and(shr( 6, input), 0x3F))))
                resultPtr := add(resultPtr, 1)
                mstore8(resultPtr, mload(add(tablePtr, and(        input,  0x3F))))
                resultPtr := add(resultPtr, 1)
            }

            // padding with '='
            switch mod(mload(data), 3)
            case 1 { mstore(sub(resultPtr, 2), shl(240, 0x3d3d)) }
            case 2 { mstore(sub(resultPtr, 1), shl(248, 0x3d)) }
        }

        return result;
    }

    function decode(string memory _data) internal pure returns (bytes memory) {
        bytes memory data = bytes(_data);

        if (data.length == 0) return new bytes(0);
        require(data.length % 4 == 0, "invalid base64 decoder input");

        // load the table into memory
        bytes memory table = TABLE_DECODE;

        // every 4 characters represent 3 bytes
        uint256 decodedLen = (data.length / 4) * 3;

        // add some extra buffer at the end required for the writing
        bytes memory result = new bytes(decodedLen + 32);

        assembly {
            // padding with '='
            let lastBytes := mload(add(data, mload(data)))
            if eq(and(lastBytes, 0xFF), 0x3d) {
                decodedLen := sub(decodedLen, 1)
                if eq(and(lastBytes, 0xFFFF), 0x3d3d) {
                    decodedLen := sub(decodedLen, 1)
                }
            }

            // set the actual output length
            mstore(result, decodedLen)

            // prepare the lookup table
            let tablePtr := add(table, 1)

            // input ptr
            let dataPtr := data
            let endPtr := add(dataPtr, mload(data))

            // result ptr, jump over length
            let resultPtr := add(result, 32)

            // run over the input, 4 characters at a time
            for {} lt(dataPtr, endPtr) {}
            {
               // read 4 characters
               dataPtr := add(dataPtr, 4)
               let input := mload(dataPtr)

               // write 3 bytes
               let output := add(
                   add(
                       shl(18, and(mload(add(tablePtr, and(shr(24, input), 0xFF))), 0xFF)),
                       shl(12, and(mload(add(tablePtr, and(shr(16, input), 0xFF))), 0xFF))),
                   add(
                       shl( 6, and(mload(add(tablePtr, and(shr( 8, input), 0xFF))), 0xFF)),
                               and(mload(add(tablePtr, and(        input , 0xFF))), 0xFF)
                    )
                )
                mstore(resultPtr, shl(232, output))
                resultPtr := add(resultPtr, 3)
            }
        }

        return result;
    }
}

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



// SPDX-License-Identifier: MIT

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/token/ERC721/ERC721.sol



// SPDX-License-Identifier: MIT

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 {
        require(operator != _msgSender(), "ERC721: approve to caller");

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

    /**
     * @dev See {IERC721-isApprovedForAll}.
     */
    function isApprovedForAll(address owner, address operator) public view 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);
    }

    /**
     * @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);
    }

    /**
     * @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 of token that is not own");
        require(to != address(0), "ERC721: transfer to the zero address");

        _beforeTokenTransfer(from, to, tokenId);

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

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

        emit Transfer(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 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 {}
}

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



// SPDX-License-Identifier: MIT

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 tokenId);

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

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



// SPDX-License-Identifier: MIT

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/IERC721Receiver.sol



// SPDX-License-Identifier: MIT

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/extensions/IERC721Metadata.sol



// SPDX-License-Identifier: MIT

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/utils/Address.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

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

        (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/utils/Strings.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

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

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

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

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

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IERC165.sol";

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

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



// SPDX-License-Identifier: MIT

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);
}