// File: /contracts/resolvers/PxgResolverV1.sol



pragma solidity >=0.8.0;
pragma abicoder v2;

import "@openzeppelin/contracts/utils/introspection/ERC165Storage.sol";
import "./PublicResolver.sol";
import "../PxgRegistrar.sol";

interface NFTInterface {
  function ownerOf(uint256 tokenId) external view returns (address);
}

interface Punks {
  function punkIndexToAddress(uint256 index) external view returns (address);
}

contract PxgResolverV1 is ERC165Storage, PublicResolver {
  PxgRegistrar registrar;

  mapping(address => bool) private admin;

  constructor(
    address ens,
    address registrarAddress,
    address initialAdmin
  ) PublicResolver(ens, registrarAddress) {
    registrar = PxgRegistrar(registrarAddress);
    admin[initialAdmin] = true;
  }

  event ModifyAdmin(address adminAddr, bool value);

  modifier onlyAdmin() {
    require(admin[msg.sender], "Not admin");
    _;
  }

  function modifyAdmin(address adminAddr, bool value) public onlyAdmin {
    admin[adminAddr] = value;
    emit ModifyAdmin(adminAddr, value);
  }

  /**
   * Returns the address associated with an ENS node. Will default to owner of NFT
   * if no address has been set.
   * @param node The ENS node to query.
   * @return The associated address.
   */
  function addr(bytes32 node) public view override returns (address payable) {
    try nameWrapper.ownerOf(uint256(node)) returns (address nameOwner) {
      return payable(nameOwner);
    } catch Error(string memory) {
      // no op
    } catch (bytes memory) {
      // no op
    }
    return payable(0);
  }

  address PUNK_ADDRESS = 0xb47e3cd837dDF8e4c57F05d70Ab865de6e193BBB;

  struct NFT {
    address collectionAddress;
    uint256 tokenId;
    bool exists;
  }

  struct Sale {
    NFT nft;
    uint256 price;
  }

  // node to default avatar
  mapping(bytes32 => NFT) defaultAvatar;
  // node to gallery
  mapping(bytes32 => NFT[5]) gallery;

  event DefaultAvatarSet(
    bytes32 indexed node,
    address collection,
    uint256 tokenId
  );

  /**
    @notice Get the length of gallery array.
    @dev Can use length to iterate gallery items on client
    @param node The ENS node
    @return Returns the length of gallery array
   */
  function getGalleryLength(bytes32 node) public view returns (uint256) {
    return gallery[node].length;
  }

  function getGalleryItemAtIndex(bytes32 node, uint256 idx)
    public
    view
    returns (address, uint256)
  {
    if (
      !gallery[node][idx].exists ||
      !_isValidOwner(
        node,
        gallery[node][idx].collectionAddress,
        gallery[node][idx].tokenId
      )
    ) {
      return (address(0), uint256(0));
    }

    return _validateNftData(node, gallery[node][idx]);
  }

  function setManyGalleryItems(
    bytes32 node,
    address[] memory collections,
    uint256[] memory ids,
    uint256[] memory idx
  ) public {
    require(collections.length == ids.length);
    require(collections.length == idx.length);
    require(collections.length <= 5);

    for (uint256 i; i < collections.length; i++) {
      setGalleryItem(node, collections[i], ids[i], idx[i]);
    }
  }

  /**
    @notice Allows a node owner to set a gallery NFT.
    @dev Verifies that the owner of the ENS nodes owns the NFT. 
    @param node The ENS node
    @param collectionAddress The NFT collection address
    @param tokenId The NFT ID
    @param idx The index at which to set the gallery item
   */
  function setGalleryItem(
    bytes32 node,
    address collectionAddress,
    uint256 tokenId,
    uint256 idx
  ) public {
    require(idx <= 4, "Index out of bounds");
    require(
      _isValidOwner(node, collectionAddress, tokenId),
      "Not a valid owner"
    );
    require(isAuthorised(node), "Not authorized");
    gallery[node][idx].collectionAddress = collectionAddress;
    gallery[node][idx].tokenId = tokenId;
    gallery[node][idx].exists = true;
  }

  /**
    @notice Removes an NFT from an owners gallery.
    @param node ENS node
    @param collectionAddress NFT collection address
    @param tokenId NFT ID
    @param idx Index of gallery item to remove
   */
  function removeGalleryItem(
    bytes32 node,
    address collectionAddress,
    uint256 tokenId,
    uint256 idx
  ) public {
    require(idx <= 4, "Index out of bounds");
    require(
      _isValidOwner(node, collectionAddress, tokenId),
      "Not a valid owner"
    );
    require(isAuthorised(node), "Not authorized");
    require(gallery[node][idx].exists == true, "Index does not exist");
    // remove if last index of array
    if (idx == gallery[node].length - 1) {
      delete gallery[node][gallery[node].length - 1];
    } else {
      // Swap idx item with last item and remove last item
      gallery[node][idx] = gallery[node][gallery[node].length - 1];
      delete gallery[node][gallery[node].length - 1];
    }
  }

  /**
    @notice Checks to see if node owner is the owner of the given NFT.
    @param node The ENS node
    @param collection The NFT collection address
    @param tokenId The NFT ID
   */
  function _isValidOwner(
    bytes32 node,
    address collection,
    uint256 tokenId
  ) internal view returns (bool) {
    if (collection == PUNK_ADDRESS) {
      return Punks(PUNK_ADDRESS).punkIndexToAddress(tokenId) == addr(node);
    } else {
      try NFTInterface(collection).ownerOf(tokenId) returns (
        address ownerAddr
      ) {
        return ownerAddr == addr(node);
      } catch Error(
        string memory /*reason*/
      ) {
        return false;
      } catch Panic(
        uint256 /*errorCode*/
      ) {
        return false;
      } catch (
        bytes memory /*lowLevelData*/
      ) {
        return false;
      }
    }
  }

  /**
    @notice Validates that the node owner is the owner of the NFT
    @dev May return address 0 uint 0
    @param node ENS node
    @param nft NFT struct
    @return Returns the NFT address and ID 
   */
  function _validateNftData(bytes32 node, NFT memory nft)
    internal
    view
    returns (address, uint256)
  {
    if (nft.exists && _isValidOwner(node, nft.collectionAddress, nft.tokenId)) {
      return (nft.collectionAddress, nft.tokenId);
    }
    return (address(0), uint256(0));
  }

  /**
    @notice Get the default avatar.
    @dev May return address 0 and uint 0 if not set, or now longer owner
    @param node ENS node
    @return Returns the address of the collection and NFT token ID
   */
  function getDefaultAvatar(bytes32 node)
    public
    view
    returns (address, uint256)
  {
    NFT memory nft = defaultAvatar[node];
    return _validateNftData(node, nft);
  }

  /**
    @notice Sets the default NFT avatar for a given node. 
    @dev Emits event
    @param node The ENS node
    @param collection The NFT collection address
    @param tokenId The NFT ID
   */
  function setDefaultAvatar(
    bytes32 node,
    address collection,
    uint256 tokenId
  ) public {
    require(isAuthorised(node), "Unauthorized");
    require(
      registrar.supportsCollection(collection),
      "Collection not supported"
    );
    require(_isValidOwner(node, collection, tokenId), "Not valid owner");
    defaultAvatar[node] = NFT(collection, tokenId, true);
    emit DefaultAvatarSet(node, collection, tokenId);
  }

  function supportsInterface(bytes4 interfaceID)
    public
    pure
    virtual
    override(ERC165Storage, PublicResolver)
    returns (bool)
  {
    return super.supportsInterface(interfaceID);
  }
}

// File: /contracts/resolvers/profiles/TextResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";

abstract contract TextResolver is ResolverBase {
    bytes4 constant private TEXT_INTERFACE_ID = 0x59d1d43c;

    event TextChanged(bytes32 indexed node, string indexed indexedKey, string key);

    mapping(bytes32=>mapping(string=>string)) texts;

    /**
     * Sets the text data associated with an ENS node and key.
     * May only be called by the owner of that node in the ENS registry.
     * @param node The node to update.
     * @param key The key to set.
     * @param value The text data value to set.
     */
    function setText(bytes32 node, string calldata key, string calldata value) external authorised(node) {
        texts[node][key] = value;
        emit TextChanged(node, key, key);
    }

    /**
     * Returns the text data associated with an ENS node and key.
     * @param node The ENS node to query.
     * @param key The text data key to query.
     * @return The associated text data.
     */
    function text(bytes32 node, string calldata key) external view returns (string memory) {
        return texts[node][key];
    }

    function supportsInterface(bytes4 interfaceID) virtual override public pure returns(bool) {
        return interfaceID == TEXT_INTERFACE_ID || super.supportsInterface(interfaceID);
    }
}

// File: /contracts/resolvers/profiles/PubkeyResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";

abstract contract PubkeyResolver is ResolverBase {
    bytes4 constant private PUBKEY_INTERFACE_ID = 0xc8690233;

    event PubkeyChanged(bytes32 indexed node, bytes32 x, bytes32 y);

    struct PublicKey {
        bytes32 x;
        bytes32 y;
    }

    mapping(bytes32=>PublicKey) pubkeys;

    /**
     * Sets the SECP256k1 public key associated with an ENS node.
     * @param node The ENS node to query
     * @param x the X coordinate of the curve point for the public key.
     * @param y the Y coordinate of the curve point for the public key.
     */
    function setPubkey(bytes32 node, bytes32 x, bytes32 y) external authorised(node) {
        pubkeys[node] = PublicKey(x, y);
        emit PubkeyChanged(node, x, y);
    }

    /**
     * Returns the SECP256k1 public key associated with an ENS node.
     * Defined in EIP 619.
     * @param node The ENS node to query
     * @return x The X coordinate of the curve point for the public key.
     * @return y The Y coordinate of the curve point for the public key.
     */
    function pubkey(bytes32 node) external view returns (bytes32 x, bytes32 y) {
        return (pubkeys[node].x, pubkeys[node].y);
    }

    function supportsInterface(bytes4 interfaceID) virtual override public pure returns(bool) {
        return interfaceID == PUBKEY_INTERFACE_ID || super.supportsInterface(interfaceID);
    }
}

// File: /contracts/resolvers/profiles/NameResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";

abstract contract NameResolver is ResolverBase {
    bytes4 constant private NAME_INTERFACE_ID = 0x691f3431;

    event NameChanged(bytes32 indexed node, string name);

    mapping(bytes32=>string) names;

    /**
     * Sets the name associated with an ENS node, for reverse records.
     * May only be called by the owner of that node in the ENS registry.
     * @param node The node to update.
     * @param name The name to set.
     */
    function setName(bytes32 node, string calldata name) external authorised(node) {
        names[node] = name;
        emit NameChanged(node, name);
    }

    /**
     * Returns the name associated with an ENS node, for reverse records.
     * Defined in EIP181.
     * @param node The ENS node to query.
     * @return The associated name.
     */
    function name(bytes32 node) external view returns (string memory) {
        return names[node];
    }

    function supportsInterface(bytes4 interfaceID) virtual override public pure returns(bool) {
        return interfaceID == NAME_INTERFACE_ID || super.supportsInterface(interfaceID);
    }
}

// File: /contracts/resolvers/profiles/InterfaceResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";
import "./AddrResolver.sol";

abstract contract InterfaceResolver is ResolverBase, AddrResolver {
    bytes4 constant private INTERFACE_INTERFACE_ID = bytes4(keccak256("interfaceImplementer(bytes32,bytes4)"));
    bytes4 private constant INTERFACE_META_ID = 0x01ffc9a7;

    event InterfaceChanged(bytes32 indexed node, bytes4 indexed interfaceID, address implementer);

    mapping(bytes32=>mapping(bytes4=>address)) interfaces;

    /**
     * Sets an interface associated with a name.
     * Setting the address to 0 restores the default behaviour of querying the contract at `addr()` for interface support.
     * @param node The node to update.
     * @param interfaceID The EIP 165 interface ID.
     * @param implementer The address of a contract that implements this interface for this node.
     */
    function setInterface(bytes32 node, bytes4 interfaceID, address implementer) external authorised(node) {
        interfaces[node][interfaceID] = implementer;
        emit InterfaceChanged(node, interfaceID, implementer);
    }

    /**
     * Returns the address of a contract that implements the specified interface for this name.
     * If an implementer has not been set for this interfaceID and name, the resolver will query
     * the contract at `addr()`. If `addr()` is set, a contract exists at that address, and that
     * contract implements EIP165 and returns `true` for the specified interfaceID, its address
     * will be returned.
     * @param node The ENS node to query.
     * @param interfaceID The EIP 165 interface ID to check for.
     * @return The address that implements this interface, or 0 if the interface is unsupported.
     */
    function interfaceImplementer(bytes32 node, bytes4 interfaceID) external view returns (address) {
        address implementer = interfaces[node][interfaceID];
        if(implementer != address(0)) {
            return implementer;
        }

        address a = addr(node);
        if(a == address(0)) {
            return address(0);
        }

        (bool success, bytes memory returnData) = a.staticcall(abi.encodeWithSignature("supportsInterface(bytes4)", INTERFACE_META_ID));
        if(!success || returnData.length < 32 || returnData[31] == 0) {
            // EIP 165 not supported by target
            return address(0);
        }

        (success, returnData) = a.staticcall(abi.encodeWithSignature("supportsInterface(bytes4)", interfaceID));
        if(!success || returnData.length < 32 || returnData[31] == 0) {
            // Specified interface not supported by target
            return address(0);
        }

        return a;
    }

    function supportsInterface(bytes4 interfaceID) virtual override(AddrResolver, ResolverBase) public pure returns(bool) {
        return interfaceID == INTERFACE_INTERFACE_ID || super.supportsInterface(interfaceID);
    }
}

// File: /contracts/resolvers/profiles/DNSResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";
import "../../dnssec-oracle/RRUtils.sol";

abstract contract DNSResolver is ResolverBase {
    using RRUtils for *;
    using BytesUtils for bytes;

    bytes4 constant private DNS_RECORD_INTERFACE_ID = 0xa8fa5682;
    bytes4 constant private DNS_ZONE_INTERFACE_ID = 0x5c47637c;

    // DNSRecordChanged is emitted whenever a given node/name/resource's RRSET is updated.
    event DNSRecordChanged(bytes32 indexed node, bytes name, uint16 resource, bytes record);
    // DNSRecordDeleted is emitted whenever a given node/name/resource's RRSET is deleted.
    event DNSRecordDeleted(bytes32 indexed node, bytes name, uint16 resource);
    // DNSZoneCleared is emitted whenever a given node's zone information is cleared.
    event DNSZoneCleared(bytes32 indexed node);

    // DNSZonehashChanged is emitted whenever a given node's zone hash is updated.
    event DNSZonehashChanged(bytes32 indexed node, bytes lastzonehash, bytes zonehash);

    // Zone hashes for the domains.
    // A zone hash is an EIP-1577 content hash in binary format that should point to a
    // resource containing a single zonefile.
    // node => contenthash
    mapping(bytes32=>bytes) private zonehashes;

    // Version the mapping for each zone.  This allows users who have lost
    // track of their entries to effectively delete an entire zone by bumping
    // the version number.
    // node => version
    mapping(bytes32=>uint256) private versions;

    // The records themselves.  Stored as binary RRSETs
    // node => version => name => resource => data
    mapping(bytes32=>mapping(uint256=>mapping(bytes32=>mapping(uint16=>bytes)))) private records;

    // Count of number of entries for a given name.  Required for DNS resolvers
    // when resolving wildcards.
    // node => version => name => number of records
    mapping(bytes32=>mapping(uint256=>mapping(bytes32=>uint16))) private nameEntriesCount;

    /**
     * Set one or more DNS records.  Records are supplied in wire-format.
     * Records with the same node/name/resource must be supplied one after the
     * other to ensure the data is updated correctly. For example, if the data
     * was supplied:
     *     a.example.com IN A 1.2.3.4
     *     a.example.com IN A 5.6.7.8
     *     www.example.com IN CNAME a.example.com.
     * then this would store the two A records for a.example.com correctly as a
     * single RRSET, however if the data was supplied:
     *     a.example.com IN A 1.2.3.4
     *     www.example.com IN CNAME a.example.com.
     *     a.example.com IN A 5.6.7.8
     * then this would store the first A record, the CNAME, then the second A
     * record which would overwrite the first.
     *
     * @param node the namehash of the node for which to set the records
     * @param data the DNS wire format records to set
     */
    function setDNSRecords(bytes32 node, bytes calldata data) external authorised(node) {
        uint16 resource = 0;
        uint256 offset = 0;
        bytes memory name;
        bytes memory value;
        bytes32 nameHash;
        // Iterate over the data to add the resource records
        for (RRUtils.RRIterator memory iter = data.iterateRRs(0); !iter.done(); iter.next()) {
            if (resource == 0) {
                resource = iter.dnstype;
                name = iter.name();
                nameHash = keccak256(abi.encodePacked(name));
                value = bytes(iter.rdata());
            } else {
                bytes memory newName = iter.name();
                if (resource != iter.dnstype || !name.equals(newName)) {
                    setDNSRRSet(node, name, resource, data, offset, iter.offset - offset, value.length == 0);
                    resource = iter.dnstype;
                    offset = iter.offset;
                    name = newName;
                    nameHash = keccak256(name);
                    value = bytes(iter.rdata());
                }
            }
        }
        if (name.length > 0) {
            setDNSRRSet(node, name, resource, data, offset, data.length - offset, value.length == 0);
        }
    }

    /**
     * Obtain a DNS record.
     * @param node the namehash of the node for which to fetch the record
     * @param name the keccak-256 hash of the fully-qualified name for which to fetch the record
     * @param resource the ID of the resource as per https://en.wikipedia.org/wiki/List_of_DNS_record_types
     * @return the DNS record in wire format if present, otherwise empty
     */
    function dnsRecord(bytes32 node, bytes32 name, uint16 resource) public view returns (bytes memory) {
        return records[node][versions[node]][name][resource];
    }

    /**
     * Check if a given node has records.
     * @param node the namehash of the node for which to check the records
     * @param name the namehash of the node for which to check the records
     */
    function hasDNSRecords(bytes32 node, bytes32 name) public view returns (bool) {
        return (nameEntriesCount[node][versions[node]][name] != 0);
    }

    /**
     * Clear all information for a DNS zone.
     * @param node the namehash of the node for which to clear the zone
     */
    function clearDNSZone(bytes32 node) public authorised(node) {
        versions[node]++;
        emit DNSZoneCleared(node);
    }

    /**
     * setZonehash sets the hash for the zone.
     * May only be called by the owner of that node in the ENS registry.
     * @param node The node to update.
     * @param hash The zonehash to set
     */
    function setZonehash(bytes32 node, bytes calldata hash) external authorised(node) {
        bytes memory oldhash = zonehashes[node];
        zonehashes[node] = hash;
        emit DNSZonehashChanged(node, oldhash, hash);
    }

    /**
     * zonehash obtains the hash for the zone.
     * @param node The ENS node to query.
     * @return The associated contenthash.
     */
    function zonehash(bytes32 node) external view returns (bytes memory) {
        return zonehashes[node];
    }

    function supportsInterface(bytes4 interfaceID) virtual override public pure returns(bool) {
        return interfaceID == DNS_RECORD_INTERFACE_ID ||
               interfaceID == DNS_ZONE_INTERFACE_ID ||
               super.supportsInterface(interfaceID);
    }

    function setDNSRRSet(
        bytes32 node,
        bytes memory name,
        uint16 resource,
        bytes memory data,
        uint256 offset,
        uint256 size,
        bool deleteRecord) private
    {
        uint256 version = versions[node];
        bytes32 nameHash = keccak256(name);
        bytes memory rrData = data.substring(offset, size);
        if (deleteRecord) {
            if (records[node][version][nameHash][resource].length != 0) {
                nameEntriesCount[node][version][nameHash]--;
            }
            delete(records[node][version][nameHash][resource]);
            emit DNSRecordDeleted(node, name, resource);
        } else {
            if (records[node][version][nameHash][resource].length == 0) {
                nameEntriesCount[node][version][nameHash]++;
            }
            records[node][version][nameHash][resource] = rrData;
            emit DNSRecordChanged(node, name, resource, rrData);
        }
    }
}

// File: /contracts/resolvers/profiles/ContentHashResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";

abstract contract ContentHashResolver is ResolverBase {
    bytes4 constant private CONTENT_HASH_INTERFACE_ID = 0xbc1c58d1;

    event ContenthashChanged(bytes32 indexed node, bytes hash);

    mapping(bytes32=>bytes) hashes;

    /**
     * Sets the contenthash associated with an ENS node.
     * May only be called by the owner of that node in the ENS registry.
     * @param node The node to update.
     * @param hash The contenthash to set
     */
    function setContenthash(bytes32 node, bytes calldata hash) external authorised(node) {
        hashes[node] = hash;
        emit ContenthashChanged(node, hash);
    }

    /**
     * Returns the contenthash associated with an ENS node.
     * @param node The ENS node to query.
     * @return The associated contenthash.
     */
    function contenthash(bytes32 node) external view returns (bytes memory) {
        return hashes[node];
    }

    function supportsInterface(bytes4 interfaceID) virtual override public pure returns(bool) {
        return interfaceID == CONTENT_HASH_INTERFACE_ID || super.supportsInterface(interfaceID);
    }
}

// File: /contracts/resolvers/profiles/AddrResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";

abstract contract AddrResolver is ResolverBase {
  bytes4 private constant ADDR_INTERFACE_ID = 0x3b3b57de;
  bytes4 private constant ADDRESS_INTERFACE_ID = 0xf1cb7e06;
  uint256 constant COIN_TYPE_ETH = 60;

  event AddrChanged(bytes32 indexed node, address a);
  event AddressChanged(
    bytes32 indexed node,
    uint256 coinType,
    bytes newAddress
  );

  mapping(bytes32 => mapping(uint256 => bytes)) _addresses;

  /**
   * Returns the address associated with an ENS node.
   * @param node The ENS node to query.
   * @return The associated address.
   */
  function addr(bytes32 node) public view virtual returns (address payable) {
    bytes memory a = addr(node, COIN_TYPE_ETH);
    if (a.length == 0) {
      return payable(0);
    }
    return bytesToAddress(a);
  }

  function addr(bytes32 node, uint256 coinType)
    public
    view
    virtual
    returns (bytes memory)
  {
    return _addresses[node][coinType];
  }

  function supportsInterface(bytes4 interfaceID)
    public
    pure
    virtual
    override
    returns (bool)
  {
    return
      interfaceID == ADDR_INTERFACE_ID ||
      interfaceID == ADDRESS_INTERFACE_ID ||
      super.supportsInterface(interfaceID);
  }
}

// File: /contracts/resolvers/profiles/ABIResolver.sol



pragma solidity >=0.8.4;
import "../ResolverBase.sol";

abstract contract ABIResolver is ResolverBase {
    bytes4 constant private ABI_INTERFACE_ID = 0x2203ab56;

    event ABIChanged(bytes32 indexed node, uint256 indexed contentType);

    mapping(bytes32=>mapping(uint256=>bytes)) abis;

    /**
     * Sets the ABI associated with an ENS node.
     * Nodes may have one ABI of each content type. To remove an ABI, set it to
     * the empty string.
     * @param node The node to update.
     * @param contentType The content type of the ABI
     * @param data The ABI data.
     */
    function setABI(bytes32 node, uint256 contentType, bytes calldata data) external authorised(node) {
        // Content types must be powers of 2
        require(((contentType - 1) & contentType) == 0);

        abis[node][contentType] = data;
        emit ABIChanged(node, contentType);
    }

    /**
     * Returns the ABI associated with an ENS node.
     * Defined in EIP205.
     * @param node The ENS node to query
     * @param contentTypes A bitwise OR of the ABI formats accepted by the caller.
     * @return contentType The content type of the return value
     * @return data The ABI data
     */
    function ABI(bytes32 node, uint256 contentTypes) external view returns (uint256, bytes memory) {
        mapping(uint256=>bytes) storage abiset = abis[node];

        for (uint256 contentType = 1; contentType <= contentTypes; contentType <<= 1) {
            if ((contentType & contentTypes) != 0 && abiset[contentType].length > 0) {
                return (contentType, abiset[contentType]);
            }
        }

        return (0, bytes(""));
    }

    function supportsInterface(bytes4 interfaceID) virtual override public pure returns(bool) {
        return interfaceID == ABI_INTERFACE_ID || super.supportsInterface(interfaceID);
    }
}

// File: /contracts/resolvers/ResolverBase.sol



pragma solidity >=0.8.4;
abstract contract ResolverBase {
    bytes4 private constant INTERFACE_META_ID = 0x01ffc9a7;

    function supportsInterface(bytes4 interfaceID) virtual public pure returns(bool) {
        return interfaceID == INTERFACE_META_ID;
    }

    function isAuthorised(bytes32 node) internal virtual view returns(bool);

    modifier authorised(bytes32 node) {
        require(isAuthorised(node));
        _;
    }

    function bytesToAddress(bytes memory b) internal pure returns(address payable a) {
        require(b.length == 20);
        assembly {
            a := div(mload(add(b, 32)), exp(256, 12))
        }
    }

    function addressToBytes(address a) internal pure returns(bytes memory b) {
        b = new bytes(20);
        assembly {
            mstore(add(b, 32), mul(a, exp(256, 12)))
        }
    }
}

// File: /contracts/resolvers/PublicResolver.sol



pragma solidity >=0.8.4;

import "../ENS.sol";
import "./profiles/ABIResolver.sol";
import "./profiles/AddrResolver.sol";
import "./profiles/ContentHashResolver.sol";
import "./profiles/DNSResolver.sol";
import "./profiles/InterfaceResolver.sol";
import "./profiles/NameResolver.sol";
import "./profiles/PubkeyResolver.sol";
import "./profiles/TextResolver.sol";

interface INameWrapper {
  function ownerOf(uint256 id) external view returns (address);
}

/**'fis
 * A simple resolver anyone can use; only allows the owner of a node to set its
 * address.
 */
contract PublicResolver is
  ABIResolver,
  AddrResolver,
  ContentHashResolver,
  DNSResolver,
  InterfaceResolver,
  NameResolver,
  PubkeyResolver,
  TextResolver
{
  ENS ens;
  INameWrapper nameWrapper;

  /**
   * A mapping of operators. An address that is authorised for an address
   * may make any changes to the name that the owner could, but may not update
   * the set of authorisations.
   * (owner, operator) => approved
   */
  mapping(address => mapping(address => bool)) private _operatorApprovals;

  // Logged when an operator is added or removed.
  event ApprovalForAll(
    address indexed owner,
    address indexed operator,
    bool approved
  );

  constructor(address _ens, address wrapperAddress) {
    ens = ENS(_ens);
    nameWrapper = INameWrapper(wrapperAddress);
  }

  function isAuthorised(bytes32 node) internal view override returns (bool) {
    return msg.sender == addr(node);
  }

  function multicall(bytes[] calldata data)
    external
    returns (bytes[] memory results)
  {
    results = new bytes[](data.length);
    for (uint256 i = 0; i < data.length; i++) {
      (bool success, bytes memory result) = address(this).delegatecall(data[i]);
      require(success);
      results[i] = result;
    }
    return results;
  }

  function supportsInterface(bytes4 interfaceID)
    public
    pure
    virtual
    override(
      ABIResolver,
      AddrResolver,
      ContentHashResolver,
      DNSResolver,
      InterfaceResolver,
      NameResolver,
      PubkeyResolver,
      TextResolver
    )
    returns (bool)
  {
    return super.supportsInterface(interfaceID);
  }
}

// File: /contracts/dnssec-oracle/RRUtils.sol



pragma solidity ^0.8.4;

import "./BytesUtils.sol";
import "@ensdomains/buffer/contracts/Buffer.sol";

/**
 * @dev RRUtils is a library that provides utilities for parsing DNS resource records.
 */
library RRUtils {
  using BytesUtils for *;
  using Buffer for *;

  /**
   * @dev Returns the number of bytes in the DNS name at 'offset' in 'self'.
   * @param self The byte array to read a name from.
   * @param offset The offset to start reading at.
   * @return The length of the DNS name at 'offset', in bytes.
   */
  function nameLength(bytes memory self, uint256 offset)
    internal
    pure
    returns (uint256)
  {
    uint256 idx = offset;
    while (true) {
      assert(idx < self.length);
      uint256 labelLen = self.readUint8(idx);
      idx += labelLen + 1;
      if (labelLen == 0) {
        break;
      }
    }
    return idx - offset;
  }

  /**
   * @dev Returns a DNS format name at the specified offset of self.
   * @param self The byte array to read a name from.
   * @param offset The offset to start reading at.
   * @return ret The name.
   */
  function readName(bytes memory self, uint256 offset)
    internal
    pure
    returns (bytes memory ret)
  {
    uint256 len = nameLength(self, offset);
    return self.substring(offset, len);
  }

  /**
   * @dev Returns the number of labels in the DNS name at 'offset' in 'self'.
   * @param self The byte array to read a name from.
   * @param offset The offset to start reading at.
   * @return The number of labels in the DNS name at 'offset', in bytes.
   */
  function labelCount(bytes memory self, uint256 offset)
    internal
    pure
    returns (uint256)
  {
    uint256 count = 0;
    while (true) {
      assert(offset < self.length);
      uint256 labelLen = self.readUint8(offset);
      offset += labelLen + 1;
      if (labelLen == 0) {
        break;
      }
      count += 1;
    }
    return count;
  }

  uint256 constant RRSIG_TYPE = 0;
  uint256 constant RRSIG_ALGORITHM = 2;
  uint256 constant RRSIG_LABELS = 3;
  uint256 constant RRSIG_TTL = 4;
  uint256 constant RRSIG_EXPIRATION = 8;
  uint256 constant RRSIG_INCEPTION = 12;
  uint256 constant RRSIG_KEY_TAG = 16;
  uint256 constant RRSIG_SIGNER_NAME = 18;

  struct SignedSet {
    uint16 typeCovered;
    uint8 algorithm;
    uint8 labels;
    uint32 ttl;
    uint32 expiration;
    uint32 inception;
    uint16 keytag;
    bytes signerName;
    bytes data;
    bytes name;
  }

  function readSignedSet(bytes memory data)
    internal
    pure
    returns (SignedSet memory self)
  {
    self.typeCovered = data.readUint16(RRSIG_TYPE);
    self.algorithm = data.readUint8(RRSIG_ALGORITHM);
    self.labels = data.readUint8(RRSIG_LABELS);
    self.ttl = data.readUint32(RRSIG_TTL);
    self.expiration = data.readUint32(RRSIG_EXPIRATION);
    self.inception = data.readUint32(RRSIG_INCEPTION);
    self.keytag = data.readUint16(RRSIG_KEY_TAG);
    self.signerName = readName(data, RRSIG_SIGNER_NAME);
    self.data = data.substring(
      RRSIG_SIGNER_NAME + self.signerName.length,
      data.length - RRSIG_SIGNER_NAME - self.signerName.length
    );
  }

  function rrs(SignedSet memory rrset)
    internal
    pure
    returns (RRIterator memory)
  {
    return iterateRRs(rrset.data, 0);
  }

  /**
   * @dev An iterator over resource records.
   */
  struct RRIterator {
    bytes data;
    uint256 offset;
    uint16 dnstype;
    uint16 class;
    uint32 ttl;
    uint256 rdataOffset;
    uint256 nextOffset;
  }

  /**
   * @dev Begins iterating over resource records.
   * @param self The byte string to read from.
   * @param offset The offset to start reading at.
   * @return ret An iterator object.
   */
  function iterateRRs(bytes memory self, uint256 offset)
    internal
    pure
    returns (RRIterator memory ret)
  {
    ret.data = self;
    ret.nextOffset = offset;
    next(ret);
  }

  /**
   * @dev Returns true iff there are more RRs to iterate.
   * @param iter The iterator to check.
   * @return True iff the iterator has finished.
   */
  function done(RRIterator memory iter) internal pure returns (bool) {
    return iter.offset >= iter.data.length;
  }

  /**
   * @dev Moves the iterator to the next resource record.
   * @param iter The iterator to advance.
   */
  function next(RRIterator memory iter) internal pure {
    iter.offset = iter.nextOffset;
    if (iter.offset >= iter.data.length) {
      return;
    }

    // Skip the name
    uint256 off = iter.offset + nameLength(iter.data, iter.offset);

    // Read type, class, and ttl
    iter.dnstype = iter.data.readUint16(off);
    off += 2;
    iter.class = iter.data.readUint16(off);
    off += 2;
    iter.ttl = iter.data.readUint32(off);
    off += 4;

    // Read the rdata
    uint256 rdataLength = iter.data.readUint16(off);
    off += 2;
    iter.rdataOffset = off;
    iter.nextOffset = off + rdataLength;
  }

  /**
   * @dev Returns the name of the current record.
   * @param iter The iterator.
   * @return A new bytes object containing the owner name from the RR.
   */
  function name(RRIterator memory iter) internal pure returns (bytes memory) {
    return iter.data.substring(iter.offset, nameLength(iter.data, iter.offset));
  }

  /**
   * @dev Returns the rdata portion of the current record.
   * @param iter The iterator.
   * @return A new bytes object containing the RR's RDATA.
   */
  function rdata(RRIterator memory iter) internal pure returns (bytes memory) {
    return
      iter.data.substring(iter.rdataOffset, iter.nextOffset - iter.rdataOffset);
  }

  uint256 constant DNSKEY_FLAGS = 0;
  uint256 constant DNSKEY_PROTOCOL = 2;
  uint256 constant DNSKEY_ALGORITHM = 3;
  uint256 constant DNSKEY_PUBKEY = 4;

  struct DNSKEY {
    uint16 flags;
    uint8 protocol;
    uint8 algorithm;
    bytes publicKey;
  }

  function readDNSKEY(
    bytes memory data,
    uint256 offset,
    uint256 length
  ) internal pure returns (DNSKEY memory self) {
    self.flags = data.readUint16(offset + DNSKEY_FLAGS);
    self.protocol = data.readUint8(offset + DNSKEY_PROTOCOL);
    self.algorithm = data.readUint8(offset + DNSKEY_ALGORITHM);
    self.publicKey = data.substring(
      offset + DNSKEY_PUBKEY,
      length - DNSKEY_PUBKEY
    );
  }

  uint256 constant DS_KEY_TAG = 0;
  uint256 constant DS_ALGORITHM = 2;
  uint256 constant DS_DIGEST_TYPE = 3;
  uint256 constant DS_DIGEST = 4;

  struct DS {
    uint16 keytag;
    uint8 algorithm;
    uint8 digestType;
    bytes digest;
  }

  function readDS(
    bytes memory data,
    uint256 offset,
    uint256 length
  ) internal pure returns (DS memory self) {
    self.keytag = data.readUint16(offset + DS_KEY_TAG);
    self.algorithm = data.readUint8(offset + DS_ALGORITHM);
    self.digestType = data.readUint8(offset + DS_DIGEST_TYPE);
    self.digest = data.substring(offset + DS_DIGEST, length - DS_DIGEST);
  }

  struct NSEC3 {
    uint8 hashAlgorithm;
    uint8 flags;
    uint16 iterations;
    bytes salt;
    bytes32 nextHashedOwnerName;
    bytes typeBitmap;
  }

  uint256 constant NSEC3_HASH_ALGORITHM = 0;
  uint256 constant NSEC3_FLAGS = 1;
  uint256 constant NSEC3_ITERATIONS = 2;
  uint256 constant NSEC3_SALT_LENGTH = 4;
  uint256 constant NSEC3_SALT = 5;

  function readNSEC3(
    bytes memory data,
    uint256 offset,
    uint256 length
  ) internal pure returns (NSEC3 memory self) {
    uint256 end = offset + length;
    self.hashAlgorithm = data.readUint8(offset + NSEC3_HASH_ALGORITHM);
    self.flags = data.readUint8(offset + NSEC3_FLAGS);
    self.iterations = data.readUint16(offset + NSEC3_ITERATIONS);
    uint8 saltLength = data.readUint8(offset + NSEC3_SALT_LENGTH);
    offset = offset + NSEC3_SALT;
    self.salt = data.substring(offset, saltLength);
    offset += saltLength;
    uint8 nextLength = data.readUint8(offset);
    require(nextLength <= 32);
    offset += 1;
    self.nextHashedOwnerName = data.readBytesN(offset, nextLength);
    offset += nextLength;
    self.typeBitmap = data.substring(offset, end - offset);
  }

  function checkTypeBitmap(NSEC3 memory self, uint16 rrtype)
    internal
    pure
    returns (bool)
  {
    return checkTypeBitmap(self.typeBitmap, 0, rrtype);
  }

  /**
   * @dev Checks if a given RR type exists in a type bitmap.
   * @param bitmap The byte string to read the type bitmap from.
   * @param offset The offset to start reading at.
   * @param rrtype The RR type to check for.
   * @return True if the type is found in the bitmap, false otherwise.
   */
  function checkTypeBitmap(
    bytes memory bitmap,
    uint256 offset,
    uint16 rrtype
  ) internal pure returns (bool) {
    uint8 typeWindow = uint8(rrtype >> 8);
    uint8 windowByte = uint8((rrtype & 0xff) / 8);
    uint8 windowBitmask = uint8(uint8(1) << (uint8(7) - uint8(rrtype & 0x7)));
    for (uint256 off = offset; off < bitmap.length; ) {
      uint8 window = bitmap.readUint8(off);
      uint8 len = bitmap.readUint8(off + 1);
      if (typeWindow < window) {
        // We've gone past our window; it's not here.
        return false;
      } else if (typeWindow == window) {
        // Check this type bitmap
        if (len <= windowByte) {
          // Our type is past the end of the bitmap
          return false;
        }
        return (bitmap.readUint8(off + windowByte + 2) & windowBitmask) != 0;
      } else {
        // Skip this type bitmap
        off += len + 2;
      }
    }

    return false;
  }

  function compareNames(bytes memory self, bytes memory other)
    internal
    pure
    returns (int256)
  {
    if (self.equals(other)) {
      return 0;
    }

    uint256 off;
    uint256 otheroff;
    uint256 prevoff;
    uint256 otherprevoff;
    uint256 counts = labelCount(self, 0);
    uint256 othercounts = labelCount(other, 0);

    // Keep removing labels from the front of the name until both names are equal length
    while (counts > othercounts) {
      prevoff = off;
      off = progress(self, off);
      counts--;
    }

    while (othercounts > counts) {
      otherprevoff = otheroff;
      otheroff = progress(other, otheroff);
      othercounts--;
    }

    // Compare the last nonequal labels to each other
    while (counts > 0 && !self.equals(off, other, otheroff)) {
      prevoff = off;
      off = progress(self, off);
      otherprevoff = otheroff;
      otheroff = progress(other, otheroff);
      counts -= 1;
    }

    if (off == 0) {
      return -1;
    }
    if (otheroff == 0) {
      return 1;
    }

    return
      self.compare(
        prevoff + 1,
        self.readUint8(prevoff),
        other,
        otherprevoff + 1,
        other.readUint8(otherprevoff)
      );
  }

  /**
   * @dev Compares two serial numbers using RFC1982 serial number math.
   */
  function serialNumberGte(uint32 i1, uint32 i2) internal pure returns (bool) {
    return int32(i1) - int32(i2) >= 0;
  }

  function progress(bytes memory body, uint256 off)
    internal
    pure
    returns (uint256)
  {
    return off + 1 + body.readUint8(off);
  }
}

// File: /contracts/dnssec-oracle/BytesUtils.sol



pragma solidity ^0.8.4;

library BytesUtils {
    /*
    * @dev Returns the keccak-256 hash of a byte range.
    * @param self The byte string to hash.
    * @param offset The position to start hashing at.
    * @param len The number of bytes to hash.
    * @return The hash of the byte range.
    */
    function keccak(bytes memory self, uint offset, uint len) internal pure returns (bytes32 ret) {
        require(offset + len <= self.length);
        assembly {
            ret := keccak256(add(add(self, 32), offset), len)
        }
    }


    /*
    * @dev Returns a positive number if `other` comes lexicographically after
    *      `self`, a negative number if it comes before, or zero if the
    *      contents of the two bytes are equal.
    * @param self The first bytes to compare.
    * @param other The second bytes to compare.
    * @return The result of the comparison.
    */
    function compare(bytes memory self, bytes memory other) internal pure returns (int) {
        return compare(self, 0, self.length, other, 0, other.length);
    }

    /*
    * @dev Returns a positive number if `other` comes lexicographically after
    *      `self`, a negative number if it comes before, or zero if the
    *      contents of the two bytes are equal. Comparison is done per-rune,
    *      on unicode codepoints.
    * @param self The first bytes to compare.
    * @param offset The offset of self.
    * @param len    The length of self.
    * @param other The second bytes to compare.
    * @param otheroffset The offset of the other string.
    * @param otherlen    The length of the other string.
    * @return The result of the comparison.
    */
    function compare(bytes memory self, uint offset, uint len, bytes memory other, uint otheroffset, uint otherlen) internal pure returns (int) {
        uint shortest = len;
        if (otherlen < len)
        shortest = otherlen;

        uint selfptr;
        uint otherptr;

        assembly {
            selfptr := add(self, add(offset, 32))
            otherptr := add(other, add(otheroffset, 32))
        }
        for (uint idx = 0; idx < shortest; idx += 32) {
            uint a;
            uint b;
            assembly {
                a := mload(selfptr)
                b := mload(otherptr)
            }
            if (a != b) {
                // Mask out irrelevant bytes and check again
                uint mask;
                if (shortest > 32) {
                    mask = type(uint256).max;
                } else {
                    mask = ~(2 ** (8 * (32 - shortest + idx)) - 1);
                }
                int diff = int(a & mask) - int(b & mask);
                if (diff != 0)
                return diff;
            }
            selfptr += 32;
            otherptr += 32;
        }

        return int(len) - int(otherlen);
    }

    /*
    * @dev Returns true if the two byte ranges are equal.
    * @param self The first byte range to compare.
    * @param offset The offset into the first byte range.
    * @param other The second byte range to compare.
    * @param otherOffset The offset into the second byte range.
    * @param len The number of bytes to compare
    * @return True if the byte ranges are equal, false otherwise.
    */
    function equals(bytes memory self, uint offset, bytes memory other, uint otherOffset, uint len) internal pure returns (bool) {
        return keccak(self, offset, len) == keccak(other, otherOffset, len);
    }

    /*
    * @dev Returns true if the two byte ranges are equal with offsets.
    * @param self The first byte range to compare.
    * @param offset The offset into the first byte range.
    * @param other The second byte range to compare.
    * @param otherOffset The offset into the second byte range.
    * @return True if the byte ranges are equal, false otherwise.
    */
    function equals(bytes memory self, uint offset, bytes memory other, uint otherOffset) internal pure returns (bool) {
        return keccak(self, offset, self.length - offset) == keccak(other, otherOffset, other.length - otherOffset);
    }

    /*
    * @dev Compares a range of 'self' to all of 'other' and returns True iff
    *      they are equal.
    * @param self The first byte range to compare.
    * @param offset The offset into the first byte range.
    * @param other The second byte range to compare.
    * @return True if the byte ranges are equal, false otherwise.
    */
    function equals(bytes memory self, uint offset, bytes memory other) internal pure returns (bool) {
        return self.length >= offset + other.length && equals(self, offset, other, 0, other.length);
    }

    /*
    * @dev Returns true if the two byte ranges are equal.
    * @param self The first byte range to compare.
    * @param other The second byte range to compare.
    * @return True if the byte ranges are equal, false otherwise.
    */
    function equals(bytes memory self, bytes memory other) internal pure returns(bool) {
        return self.length == other.length && equals(self, 0, other, 0, self.length);
    }

    /*
    * @dev Returns the 8-bit number at the specified index of self.
    * @param self The byte string.
    * @param idx The index into the bytes
    * @return The specified 8 bits of the string, interpreted as an integer.
    */
    function readUint8(bytes memory self, uint idx) internal pure returns (uint8 ret) {
        return uint8(self[idx]);
    }

    /*
    * @dev Returns the 16-bit number at the specified index of self.
    * @param self The byte string.
    * @param idx The index into the bytes
    * @return The specified 16 bits of the string, interpreted as an integer.
    */
    function readUint16(bytes memory self, uint idx) internal pure returns (uint16 ret) {
        require(idx + 2 <= self.length);
        assembly {
            ret := and(mload(add(add(self, 2), idx)), 0xFFFF)
        }
    }

    /*
    * @dev Returns the 32-bit number at the specified index of self.
    * @param self The byte string.
    * @param idx The index into the bytes
    * @return The specified 32 bits of the string, interpreted as an integer.
    */
    function readUint32(bytes memory self, uint idx) internal pure returns (uint32 ret) {
        require(idx + 4 <= self.length);
        assembly {
            ret := and(mload(add(add(self, 4), idx)), 0xFFFFFFFF)
        }
    }

    /*
    * @dev Returns the 32 byte value at the specified index of self.
    * @param self The byte string.
    * @param idx The index into the bytes
    * @return The specified 32 bytes of the string.
    */
    function readBytes32(bytes memory self, uint idx) internal pure returns (bytes32 ret) {
        require(idx + 32 <= self.length);
        assembly {
            ret := mload(add(add(self, 32), idx))
        }
    }

    /*
    * @dev Returns the 32 byte value at the specified index of self.
    * @param self The byte string.
    * @param idx The index into the bytes
    * @return The specified 32 bytes of the string.
    */
    function readBytes20(bytes memory self, uint idx) internal pure returns (bytes20 ret) {
        require(idx + 20 <= self.length);
        assembly {
            ret := and(mload(add(add(self, 32), idx)), 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF000000000000000000000000)
        }
    }

    /*
    * @dev Returns the n byte value at the specified index of self.
    * @param self The byte string.
    * @param idx The index into the bytes.
    * @param len The number of bytes.
    * @return The specified 32 bytes of the string.
    */
    function readBytesN(bytes memory self, uint idx, uint len) internal pure returns (bytes32 ret) {
        require(len <= 32);
        require(idx + len <= self.length);
        assembly {
            let mask := not(sub(exp(256, sub(32, len)), 1))
            ret := and(mload(add(add(self, 32), idx)),  mask)
        }
    }

    function memcpy(uint dest, uint src, uint len) private pure {
        // Copy word-length chunks while possible
        for (; len >= 32; len -= 32) {
            assembly {
                mstore(dest, mload(src))
            }
            dest += 32;
            src += 32;
        }

        // Copy remaining bytes
        unchecked {
            uint mask = (256 ** (32 - len)) - 1;
            assembly {
                let srcpart := and(mload(src), not(mask))
                let destpart := and(mload(dest), mask)
                mstore(dest, or(destpart, srcpart))
            }
        }
    }

    /*
    * @dev Copies a substring into a new byte string.
    * @param self The byte string to copy from.
    * @param offset The offset to start copying at.
    * @param len The number of bytes to copy.
    */
    function substring(bytes memory self, uint offset, uint len) internal pure returns(bytes memory) {
        require(offset + len <= self.length);

        bytes memory ret = new bytes(len);
        uint dest;
        uint src;

        assembly {
            dest := add(ret, 32)
            src := add(add(self, 32), offset)
        }
        memcpy(dest, src, len);

        return ret;
    }

    // Maps characters from 0x30 to 0x7A to their base32 values.
    // 0xFF represents invalid characters in that range.
    bytes constant base32HexTable = hex'00010203040506070809FFFFFFFFFFFFFF0A0B0C0D0E0F101112131415161718191A1B1C1D1E1FFFFFFFFFFFFFFFFFFFFF0A0B0C0D0E0F101112131415161718191A1B1C1D1E1F';

    /**
     * @dev Decodes unpadded base32 data of up to one word in length.
     * @param self The data to decode.
     * @param off Offset into the string to start at.
     * @param len Number of characters to decode.
     * @return The decoded data, left aligned.
     */
    function base32HexDecodeWord(bytes memory self, uint off, uint len) internal pure returns(bytes32) {
        require(len <= 52);

        uint ret = 0;
        uint8 decoded;
        for(uint i = 0; i < len; i++) {
            bytes1 char = self[off + i];
            require(char >= 0x30 && char <= 0x7A);
            decoded = uint8(base32HexTable[uint(uint8(char)) - 0x30]);
            require(decoded <= 0x20);
            if(i == len - 1) {
                break;
            }
            ret = (ret << 5) | decoded;
        }

        uint bitlen = len * 5;
        if(len % 8 == 0) {
            // Multiple of 8 characters, no padding
            ret = (ret << 5) | decoded;
        } else if(len % 8 == 2) {
            // Two extra characters - 1 byte
            ret = (ret << 3) | (decoded >> 2);
            bitlen -= 2;
        } else if(len % 8 == 4) {
            // Four extra characters - 2 bytes
            ret = (ret << 1) | (decoded >> 4);
            bitlen -= 4;
        } else if(len % 8 == 5) {
            // Five extra characters - 3 bytes
            ret = (ret << 4) | (decoded >> 1);
            bitlen -= 1;
        } else if(len % 8 == 7) {
            // Seven extra characters - 4 bytes
            ret = (ret << 2) | (decoded >> 3);
            bitlen -= 3;
        } else {
            revert();
        }

        return bytes32(ret << (256 - bitlen));
    }
}
// File: /contracts/PxgRegistrar.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "./ENS.sol";

/**
______________  ___________     _________________________ ___  
\______   \   \/  /  _____/     \_   _____/\__    ___/   |   \ 
 |     ___/\     /   \  ___      |    __)_   |    | /    ~    \
 |    |    /     \    \_\  \     |        \  |    | \    Y    /
 |____|   /___/\  \______  / /\ /_______  /  |____|  \___|_  / 
                \_/      \/  \/         \/                 \/  

www.pixelglyphs.io
*/

// ENS ADDRESS (Used on all networks) 0x00000000000C2E074eC69A0dFb2997BA6C7d2e1e

contract PxgRegistrar is ERC721Enumerable, Ownable {
  string BASE_URI;
  address RESOLVER;
  bytes32 public ROOT_NODE;
  uint256 PRICE;
  bool publicRegistrationOpen = false;
  ENS ens;
  ERC721 glyphs;

  mapping(uint256 => bool) public claimedGlyphIds;
  mapping(uint256 => address) public resolvers;
  uint256 public currentResolverVersion;
  uint256 count;

  constructor(
    string memory baseUri,
    address ensAddr,
    address glyphAddr,
    bytes32 node
  ) ERC721("PXG.ETH", "PXG.ETH") {
    BASE_URI = baseUri;
    ROOT_NODE = node;
    ens = ENS(ensAddr);
    glyphs = ERC721(glyphAddr);
    admin[msg.sender] = true;
  }

  function addResolverVersion(address resolver) public onlyOwner {
    resolvers[++currentResolverVersion] = resolver;
    RESOLVER = resolver;
  }

  function setBaseUri(string memory baseUri) public onlyOwner {
    BASE_URI = baseUri;
  }

  function _baseURI() internal view virtual override returns (string memory) {
    return BASE_URI;
  }

  function openReg() public onlyOwner {
    publicRegistrationOpen = true;
  }

  function updatePrice(uint256 price) public onlyOwner {
    PRICE = price;
  }

  function getTokenIdFromNode(bytes32 node) public pure returns (uint256) {
    return uint256(node);
  }

  function getOwnerFromNode(bytes32 node) public view returns (address) {
    return _exists(uint256(node)) ? ownerOf(uint256(node)) : address(0);
  }

  function setResolver(bytes32 node, uint256 version) public {
    require(resolvers[version] != address(0), "PXG: Resolver does not exist");
    require(
      getOwnerFromNode(node) == msg.sender,
      "PXG: Only owner can set resolver"
    );
    ens.setResolver(node, resolvers[version]);
  }

  mapping(bytes32 => string) public nodeToLabel;

  // root node is pxg.eth subnode is subdomain label
  function _register(string calldata subdomain) internal {
    bytes32 subdomainLabel = keccak256(bytes(subdomain));
    bytes32 node = keccak256(abi.encodePacked(ROOT_NODE, subdomainLabel));

    address currentOwner = ens.owner(node);

    require(currentOwner == address(0), "PXG: Name already claimed");
    require(
      resolvers[currentResolverVersion] != address(0),
      "PXG: No resolver set"
    );

    // pxg.eth, mysubdomain, address
    ens.setSubnodeOwner(ROOT_NODE, subdomainLabel, address(this));
    ens.setResolver(node, RESOLVER);
    _safeMint(msg.sender, uint256(node));
    nodeToLabel[node] = subdomain;
    count++;
  }

  function resolver(bytes32 node) external view returns (address) {
    return ens.resolver(node);
  }

  mapping(address => bool) private admin;

  modifier onlyAdmin() {
    require(admin[msg.sender], "Not admin");
    _;
  }

  event CollectionSupportAdded(address collection);

  event ModifyAdmin(address adminAddr, bool value);

  function modifyAdmin(address adminAddr, bool value) public onlyAdmin {
    admin[adminAddr] = value;
    emit ModifyAdmin(adminAddr, value);
  }

  mapping(address => bool) supportedCollections;

  function addCollectionSupport(address collection) public onlyAdmin {
    supportedCollections[collection] = true;
    emit CollectionSupportAdded(collection);
  }

  function supportsCollection(address collection) public view returns (bool) {
    return supportedCollections[collection];
  }

  event ClaimedGlyph(uint256 indexed glyphId);

  function claimGlyph(string calldata subdomain, uint256 glyphId) public {
    require(
      glyphs.ownerOf(glyphId) == msg.sender &&
        claimedGlyphIds[glyphId] == false,
      "PXG: Unauthorized"
    );

    claimedGlyphIds[glyphId] = true;
    _register(subdomain);
    emit ClaimedGlyph(glyphId);
  }

  function register(string calldata subdomain) public payable {
    require(publicRegistrationOpen || count >= 10000, "Not allowed");
    // uint256 len = bytes(subdomain).length;
    require(msg.value == PRICE, "PXG: Invalid value");
    _register(subdomain);
  }
}

// File: /contracts/ENS.sol



pragma solidity >=0.8.0;

interface ENS {
  // Logged when the owner of a node assigns a new owner to a subnode.
  event NewOwner(bytes32 indexed node, bytes32 indexed label, address owner);

  // Logged when the owner of a node transfers ownership to a new account.
  event Transfer(bytes32 indexed node, address owner);

  // Logged when the resolver for a node changes.
  event NewResolver(bytes32 indexed node, address resolver);

  // Logged when the TTL of a node changes
  event NewTTL(bytes32 indexed node, uint64 ttl);

  // Logged when an operator is added or removed.
  event ApprovalForAll(
    address indexed owner,
    address indexed operator,
    bool approved
  );

  function setRecord(
    bytes32 node,
    address owner,
    address resolver,
    uint64 ttl
  ) external virtual;

  function setSubnodeRecord(
    bytes32 node,
    bytes32 label,
    address owner,
    address resolver,
    uint64 ttl
  ) external virtual;

  function setSubnodeOwner(
    bytes32 node,
    bytes32 label,
    address owner
  ) external virtual returns (bytes32);

  function setResolver(bytes32 node, address resolver) external virtual;

  function setOwner(bytes32 node, address owner) external virtual;

  function setTTL(bytes32 node, uint64 ttl) external virtual;

  function setApprovalForAll(address operator, bool approved) external virtual;

  function owner(bytes32 node) external view virtual returns (address);

  function resolver(bytes32 node) external view virtual returns (address);

  function ttl(bytes32 node) external view virtual returns (uint64);

  function recordExists(bytes32 node) external view virtual returns (bool);

  function isApprovedForAll(address owner, address operator)
    external
    view
    virtual
    returns (bool);
}

// 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);
}

// File: @openzeppelin/contracts/utils/introspection/ERC165Storage.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./ERC165.sol";

/**
 * @dev Storage based implementation of the {IERC165} interface.
 *
 * Contracts may inherit from this and call {_registerInterface} to declare
 * their support of an interface.
 */
abstract contract ERC165Storage is ERC165 {
    /**
     * @dev Mapping of interface ids to whether or not it's supported.
     */
    mapping(bytes4 => bool) private _supportedInterfaces;

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

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

// 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/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/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/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);
    }

    function _verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) private pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                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

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

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/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/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/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/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(to).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/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: @ensdomains/buffer/contracts/Buffer.sol



pragma solidity ^0.8.4;

/**
* @dev A library for working with mutable byte buffers in Solidity.
*
* Byte buffers are mutable and expandable, and provide a variety of primitives
* for writing to them. At any time you can fetch a bytes object containing the
* current contents of the buffer. The bytes object should not be stored between
* operations, as it may change due to resizing of the buffer.
*/
library Buffer {
    /**
    * @dev Represents a mutable buffer. Buffers have a current value (buf) and
    *      a capacity. The capacity may be longer than the current value, in
    *      which case it can be extended without the need to allocate more memory.
    */
    struct buffer {
        bytes buf;
        uint capacity;
    }

    /**
    * @dev Initializes a buffer with an initial capacity.
    * @param buf The buffer to initialize.
    * @param capacity The number of bytes of space to allocate the buffer.
    * @return The buffer, for chaining.
    */
    function init(buffer memory buf, uint capacity) internal pure returns(buffer memory) {
        if (capacity % 32 != 0) {
            capacity += 32 - (capacity % 32);
        }
        // Allocate space for the buffer data
        buf.capacity = capacity;
        assembly {
            let ptr := mload(0x40)
            mstore(buf, ptr)
            mstore(ptr, 0)
            mstore(0x40, add(32, add(ptr, capacity)))
        }
        return buf;
    }

    /**
    * @dev Initializes a new buffer from an existing bytes object.
    *      Changes to the buffer may mutate the original value.
    * @param b The bytes object to initialize the buffer with.
    * @return A new buffer.
    */
    function fromBytes(bytes memory b) internal pure returns(buffer memory) {
        buffer memory buf;
        buf.buf = b;
        buf.capacity = b.length;
        return buf;
    }

    function resize(buffer memory buf, uint capacity) private pure {
        bytes memory oldbuf = buf.buf;
        init(buf, capacity);
        append(buf, oldbuf);
    }

    function max(uint a, uint b) private pure returns(uint) {
        if (a > b) {
            return a;
        }
        return b;
    }

    /**
    * @dev Sets buffer length to 0.
    * @param buf The buffer to truncate.
    * @return The original buffer, for chaining..
    */
    function truncate(buffer memory buf) internal pure returns (buffer memory) {
        assembly {
            let bufptr := mload(buf)
            mstore(bufptr, 0)
        }
        return buf;
    }

    /**
    * @dev Writes a byte string to a buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param off The start offset to write to.
    * @param data The data to append.
    * @param len The number of bytes to copy.
    * @return The original buffer, for chaining.
    */
    function write(buffer memory buf, uint off, bytes memory data, uint len) internal pure returns(buffer memory) {
        require(len <= data.length);

        if (off + len > buf.capacity) {
            resize(buf, max(buf.capacity, len + off) * 2);
        }

        uint dest;
        uint src;
        assembly {
            // Memory address of the buffer data
            let bufptr := mload(buf)
            // Length of existing buffer data
            let buflen := mload(bufptr)
            // Start address = buffer address + offset + sizeof(buffer length)
            dest := add(add(bufptr, 32), off)
            // Update buffer length if we're extending it
            if gt(add(len, off), buflen) {
                mstore(bufptr, add(len, off))
            }
            src := add(data, 32)
        }

        // Copy word-length chunks while possible
        for (; len >= 32; len -= 32) {
            assembly {
                mstore(dest, mload(src))
            }
            dest += 32;
            src += 32;
        }

        // Copy remaining bytes
        unchecked {
            uint mask = (256 ** (32 - len)) - 1;
            assembly {
                let srcpart := and(mload(src), not(mask))
                let destpart := and(mload(dest), mask)
                mstore(dest, or(destpart, srcpart))
            }
        }

        return buf;
    }

    /**
    * @dev Appends a byte string to a buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @param len The number of bytes to copy.
    * @return The original buffer, for chaining.
    */
    function append(buffer memory buf, bytes memory data, uint len) internal pure returns (buffer memory) {
        return write(buf, buf.buf.length, data, len);
    }

    /**
    * @dev Appends a byte string to a buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function append(buffer memory buf, bytes memory data) internal pure returns (buffer memory) {
        return write(buf, buf.buf.length, data, data.length);
    }

    /**
    * @dev Writes a byte to the buffer. Resizes if doing so would exceed the
    *      capacity of the buffer.
    * @param buf The buffer to append to.
    * @param off The offset to write the byte at.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function writeUint8(buffer memory buf, uint off, uint8 data) internal pure returns(buffer memory) {
        if (off >= buf.capacity) {
            resize(buf, buf.capacity * 2);
        }

        assembly {
            // Memory address of the buffer data
            let bufptr := mload(buf)
            // Length of existing buffer data
            let buflen := mload(bufptr)
            // Address = buffer address + sizeof(buffer length) + off
            let dest := add(add(bufptr, off), 32)
            mstore8(dest, data)
            // Update buffer length if we extended it
            if eq(off, buflen) {
                mstore(bufptr, add(buflen, 1))
            }
        }
        return buf;
    }

    /**
    * @dev Appends a byte to the buffer. Resizes if doing so would exceed the
    *      capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function appendUint8(buffer memory buf, uint8 data) internal pure returns(buffer memory) {
        return writeUint8(buf, buf.buf.length, data);
    }

    /**
    * @dev Writes up to 32 bytes to the buffer. Resizes if doing so would
    *      exceed the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param off The offset to write at.
    * @param data The data to append.
    * @param len The number of bytes to write (left-aligned).
    * @return The original buffer, for chaining.
    */
    function write(buffer memory buf, uint off, bytes32 data, uint len) private pure returns(buffer memory) {
        if (len + off > buf.capacity) {
            resize(buf, (len + off) * 2);
        }

        unchecked {
            uint mask = (256 ** len) - 1;
            // Right-align data
            data = data >> (8 * (32 - len));
            assembly {
                // Memory address of the buffer data
                let bufptr := mload(buf)
                // Address = buffer address + sizeof(buffer length) + off + len
                let dest := add(add(bufptr, off), len)
                mstore(dest, or(and(mload(dest), not(mask)), data))
                // Update buffer length if we extended it
                if gt(add(off, len), mload(bufptr)) {
                    mstore(bufptr, add(off, len))
                }
            }
        }
        return buf;
    }

    /**
    * @dev Writes a bytes20 to the buffer. Resizes if doing so would exceed the
    *      capacity of the buffer.
    * @param buf The buffer to append to.
    * @param off The offset to write at.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function writeBytes20(buffer memory buf, uint off, bytes20 data) internal pure returns (buffer memory) {
        return write(buf, off, bytes32(data), 20);
    }

    /**
    * @dev Appends a bytes20 to the buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chhaining.
    */
    function appendBytes20(buffer memory buf, bytes20 data) internal pure returns (buffer memory) {
        return write(buf, buf.buf.length, bytes32(data), 20);
    }

    /**
    * @dev Appends a bytes32 to the buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param data The data to append.
    * @return The original buffer, for chaining.
    */
    function appendBytes32(buffer memory buf, bytes32 data) internal pure returns (buffer memory) {
        return write(buf, buf.buf.length, data, 32);
    }

    /**
    * @dev Writes an integer to the buffer. Resizes if doing so would exceed
    *      the capacity of the buffer.
    * @param buf The buffer to append to.
    * @param off The offset to write at.
    * @param data The data to append.
    * @param len The number of bytes to write (right-aligned).
    * @return The original buffer, for chaining.
    */
    function writeInt(buffer memory buf, uint off, uint data, uint len) private pure returns(buffer memory) {
        if (len + off > buf.capacity) {
            resize(buf, (len + off) * 2);
        }

        uint mask = (256 ** len) - 1;
        assembly {
            // Memory address of the buffer data
            let bufptr := mload(buf)
            // Address = buffer address + off + sizeof(buffer length) + len
            let dest := add(add(bufptr, off), len)
            mstore(dest, or(and(mload(dest), not(mask)), data))
            // Update buffer length if we extended it
            if gt(add(off, len), mload(bufptr)) {
                mstore(bufptr, add(off, len))
            }
        }
        return buf;
    }

    /**
     * @dev Appends a byte to the end of the buffer. Resizes if doing so would
     * exceed the capacity of the buffer.
     * @param buf The buffer to append to.
     * @param data The data to append.
     * @return The original buffer.
     */
    function appendInt(buffer memory buf, uint data, uint len) internal pure returns(buffer memory) {
        return writeInt(buf, buf.buf.length, data, len);
    }
}