// File: contracts/LoanCore.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import "@openzeppelin/contracts/access/AccessControlEnumerable.sol";
import "@openzeppelin/contracts/security/Pausable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/Counters.sol";

import "./interfaces/ILoanCore.sol";
import "./interfaces/ICallDelegator.sol";
import "./interfaces/IPromissoryNote.sol";

import "./PromissoryNote.sol";
import "./libraries/InterestCalculator.sol";
import "./vault/OwnableERC721.sol";
import {
    LC_ZeroAddress,
    LC_ReusedNote,
    LC_CannotSettle,
    LC_CannotWithdraw,
    LC_ZeroAmount,
    LC_ArrayLengthMismatch,
    LC_OverMaxSplit,
    LC_CollateralInUse,
    LC_InvalidState,
    LC_NotExpired,
    LC_NonceUsed,
    LC_AffiliateCodeAlreadySet,
    LC_CallerNotLoanCore,
    LC_NoReceipt,
    LC_Shutdown
} from "./errors/Lending.sol";

/**
 * @title LoanCore
 * @author Non-Fungible Technologies, Inc.
 *
 * The LoanCore lending contract is the heart of the Arcade.xyz lending protocol.
 * It stores and maintains loan state, enforces loan lifecycle invariants, takes
 * escrow of assets during an active loans, governs the release of collateral on
 * repayment or default, and tracks signature nonces for loan consent.
 *
 * Also contains logic for approving Asset Vault calls using the
 * ICallDelegator interface.
 */
contract LoanCore is
    ILoanCore,
    InterestCalculator,
    AccessControlEnumerable,
    Pausable,
    ReentrancyGuard,
    ICallDelegator
{
    using Counters for Counters.Counter;
    using SafeERC20 for IERC20;

    // ============================================ STATE ==============================================

    // =================== Constants =====================

    bytes32 public constant ADMIN_ROLE = keccak256("ADMIN");
    bytes32 public constant ORIGINATOR_ROLE = keccak256("ORIGINATOR");
    bytes32 public constant REPAYER_ROLE = keccak256("REPAYER");
    bytes32 public constant AFFILIATE_MANAGER_ROLE = keccak256("AFFILIATE_MANAGER");
    bytes32 public constant FEE_CLAIMER_ROLE = keccak256("FEE_CLAIMER");
    bytes32 public constant SHUTDOWN_ROLE = keccak256("SHUTDOWN");

    /// @dev Max split any affiliate can earn.
    uint96 private constant MAX_AFFILIATE_SPLIT = 50_00;

    /// @dev Grace period for repaying a loan after loan duration.
    uint256 public constant GRACE_PERIOD = 10 minutes;

    // =============== Contract References ================

    IPromissoryNote public immutable override borrowerNote;
    IPromissoryNote public immutable override lenderNote;

    // =================== Loan State =====================

    /// @dev Counter for serial IDs of all loans created.
    Counters.Counter private loanIdTracker;

    /// @dev Lookup table storing loan data structure.
    mapping(uint256 => LoanLibrary.LoanData) private loans;

    /// @dev Lookup table showing what collateral is currently being escrowed.
    ///      Key is hash of (collateralAddress, collateralId).
    mapping(bytes32 => bool) private collateralInUse;

    /// @dev Lookup table showing for which user, which nonces have been used.
    ///      user => nonce => isUsed
    mapping(address => mapping(uint160 => bool)) public usedNonces;

    // =================== Fee Management =====================

    /// @dev affiliate code => affiliate split
    ///      split contains payout address and a feeShare in bps
    mapping(bytes32 => AffiliateSplit) public affiliateSplits;

    /// @dev token => user => amount fees
    mapping(address => mapping(address => uint256)) public feesWithdrawable;

    /// @dev tokenId => {token, amount}
    ///      can be withdrawn by burning LenderNote of matching tokenId
    mapping(uint256 => NoteReceipt) public noteReceipts;

    // ========================================== CONSTRUCTOR ===========================================

    /**
     * @notice Deploys the loan core contract, by setting up roles and external
     *         contract references.
     *
     * @param _borrowerNote       The address of the PromissoryNote contract representing borrower obligation.
     * @param _lenderNote         The address of the PromissoryNote contract representing lender obligation.
     */
    constructor(IPromissoryNote _borrowerNote, IPromissoryNote _lenderNote) {
        if (address(_borrowerNote) == address(0)) revert LC_ZeroAddress("borrowerNote");
        if (address(_lenderNote) == address(0)) revert LC_ZeroAddress("lenderNote");
        if (address(_borrowerNote) == address(_lenderNote)) revert LC_ReusedNote();

        _setupRole(ADMIN_ROLE, msg.sender);
        _setRoleAdmin(ADMIN_ROLE, ADMIN_ROLE);
        _setRoleAdmin(ORIGINATOR_ROLE, ADMIN_ROLE);
        _setRoleAdmin(REPAYER_ROLE, ADMIN_ROLE);
        _setRoleAdmin(FEE_CLAIMER_ROLE, ADMIN_ROLE);
        _setRoleAdmin(AFFILIATE_MANAGER_ROLE, ADMIN_ROLE);
        _setRoleAdmin(SHUTDOWN_ROLE, ADMIN_ROLE);

        /// @dev Although using references for both promissory notes, these
        ///      must be fresh versions and cannot be re-used across multiple
        ///      loanCore instances, to ensure loanId <> tokenID parity. This is
        ///      enforced via deployment processes.
        borrowerNote = _borrowerNote;
        lenderNote = _lenderNote;

        // Avoid having loanId = 0
        loanIdTracker.increment();
    }

    // ====================================== LIFECYCLE OPERATIONS ======================================

    /**
     * @notice Start a loan, matching a set of terms, with a given
     *         lender and borrower. Collects collateral and distributes
     *         principal, along with collecting an origination fee for the
     *         protocol and/or affiliate. Can only be called by OriginationController.
     *
     * @param lender                The lender for the loan.
     * @param borrower              The borrower for the loan.
     * @param terms                 The terms of the loan.
     * @param _amountFromLender     The amount of principal to be collected from the lender.
     * @param _amountToBorrower     The amount of principal to be distributed to the borrower (net after fees).
     *
     * @return loanId               The ID of the newly created loan.
     */
    function startLoan(
        address lender,
        address borrower,
        LoanLibrary.LoanTerms calldata terms,
        uint256 _amountFromLender,
        uint256 _amountToBorrower,
        LoanLibrary.FeeSnapshot calldata _feeSnapshot
    ) external override whenNotPaused onlyRole(ORIGINATOR_ROLE) nonReentrant returns (uint256 loanId) {
        // Check collateral is not already used in a loan
        bytes32 collateralKey = keccak256(abi.encode(terms.collateralAddress, terms.collateralId));
        if (collateralInUse[collateralKey]) revert LC_CollateralInUse(terms.collateralAddress, terms.collateralId);

        // Check that we will not net lose tokens
        if (_amountToBorrower > _amountFromLender) revert LC_CannotSettle(_amountToBorrower, _amountFromLender);

        // Mark collateral as escrowed
        collateralInUse[collateralKey] = true;

        // Assign fees for withdrawal
        uint256 feesEarned;
        unchecked { feesEarned = _amountFromLender - _amountToBorrower; }
        (uint256 protocolFee, uint256 affiliateFee, address affiliate) =
            _getAffiliateSplit(feesEarned, terms.affiliateCode);

        if (protocolFee > 0) feesWithdrawable[terms.payableCurrency][address(this)] += protocolFee;
        if (affiliateFee > 0) feesWithdrawable[terms.payableCurrency][affiliate] += affiliateFee;

        // Get current loanId and increment for next function call
        loanId = loanIdTracker.current();
        loanIdTracker.increment();

        // Initiate loan state
        loans[loanId] = LoanLibrary.LoanData({
            terms: terms,
            startDate: uint160(block.timestamp),
            state: LoanLibrary.LoanState.Active,
            feeSnapshot: _feeSnapshot
        });

        // Distribute notes and principal
        _mintLoanNotes(loanId, borrower, lender);

        // Collect collateral from borrower
        IERC721(terms.collateralAddress).transferFrom(borrower, address(this), terms.collateralId);

        // Collect principal from lender and send net (minus fees) amount to borrower
        _collectIfNonzero(IERC20(terms.payableCurrency), lender, _amountFromLender);
        _transferIfNonzero(IERC20(terms.payableCurrency), borrower, _amountToBorrower);

        emit LoanStarted(loanId, lender, borrower);
    }

    /**
     * @notice Repay the given loan. Can only be called by RepaymentController,
     *         which verifies repayment conditions. This method will collect
     *         the total interest due from the borrower  and redistribute
     *         principal + interest to the lender, and collateral to the borrower.
     *         All promissory notes will be burned and the loan will be marked as complete.
     *
     * @param loanId                The ID of the loan to repay.
     * @param payer                 The party repaying the loan.
     * @param _amountFromPayer      The amount of tokens to be collected from the repayer.
     * @param _amountToLender       The amount of tokens to be distributed to the lender (net after fees).
     */
    function repay(
        uint256 loanId,
        address payer,
        uint256 _amountFromPayer,
        uint256 _amountToLender
    ) external override onlyRole(REPAYER_ROLE) nonReentrant {
        LoanLibrary.LoanData memory data = _handleRepay(loanId, _amountFromPayer, _amountToLender);

        // Get promissory notes from two parties involved, then burn
        address lender = lenderNote.ownerOf(loanId);
        address borrower = borrowerNote.ownerOf(loanId);
        _burnLoanNotes(loanId);

        // Send collected principal + interest, less fees, to lender
        _collectIfNonzero(IERC20(data.terms.payableCurrency), payer, _amountFromPayer);
        _transferIfNonzero(IERC20(data.terms.payableCurrency), lender, _amountToLender);

        // Redistribute collateral
        IERC721(data.terms.collateralAddress).safeTransferFrom(address(this), borrower, data.terms.collateralId);

        emit LoanRepaid(loanId);
    }

    /**
     * @notice Let the borrower repay the given loan, but do not release principal to the lender:
     *         instead, make it available for withdrawal. Should be used in cases where the borrower wants
     *         to fulfill loan obligations but the lender cannot receive tokens (due to malicious or
     *         accidental behavior, token blacklisting etc).
     *
     * @param loanId                The ID of the loan to repay.
     * @param payer                 The party repaying the loan.
     * @param _amountFromPayer      The amount of tokens to be collected from the repayer.
     * @param _amountToLender       The amount of tokens to be distributed to the lender (net after fees).
     */
    function forceRepay(
        uint256 loanId,
        address payer,
        uint256 _amountFromPayer,
        uint256 _amountToLender
    ) external override onlyRole(REPAYER_ROLE) nonReentrant {
        LoanLibrary.LoanData memory data = _handleRepay(loanId, _amountFromPayer, _amountToLender);

        // Do not send collected principal, but make it available for withdrawal by a holder of the lender note
        noteReceipts[loanId] = NoteReceipt({
            token: data.terms.payableCurrency,
            amount: _amountToLender
        });

        // Get promissory notes from two parties involved, then burn
        // borrower note _only_ - do not burn lender note until receipt
        // is redeemed
        address borrower = borrowerNote.ownerOf(loanId);
        borrowerNote.burn(loanId);

        // Collect from borrower and redistribute collateral
        _collectIfNonzero(IERC20(data.terms.payableCurrency), payer, _amountFromPayer);
        IERC721(data.terms.collateralAddress).safeTransferFrom(address(this), borrower, data.terms.collateralId);

        emit LoanRepaid(loanId);
        emit ForceRepay(loanId);
    }

    /**
     * @notice Claim collateral on a given loan. Can only be called by RepaymentController,
     *         which verifies claim conditions. This method validates that the loan's due
     *         date has passed, and the grace period of 10 mins has also passed. Then it distributes
     *         collateral to the lender. All promissory notes will be burned and the loan
     *         will be marked as complete.
     *
     * @param loanId                              The ID of the loan to claim.
     * @param _amountFromLender                   Any claiming fees to be collected from the lender.
     */
    function claim(uint256 loanId, uint256 _amountFromLender)
        external
        override
        whenNotPaused
        onlyRole(REPAYER_ROLE)
        nonReentrant
    {
        LoanLibrary.LoanData memory data = loans[loanId];
        // Ensure valid initial loan state when claiming loan
        if (data.state != LoanLibrary.LoanState.Active) revert LC_InvalidState(data.state);

        // First check if the call is being made after the due date plus 10 min grace period.
        uint256 dueDate = data.startDate + data.terms.durationSecs + GRACE_PERIOD;
        if (dueDate >= block.timestamp) revert LC_NotExpired(dueDate);

        // State changes and cleanup
        loans[loanId].state = LoanLibrary.LoanState.Defaulted;
        collateralInUse[keccak256(abi.encode(data.terms.collateralAddress, data.terms.collateralId))] = false;

        if (_amountFromLender > 0) {
            // Assign fees for withdrawal
            (uint256 protocolFee, uint256 affiliateFee, address affiliate) =
                _getAffiliateSplit(_amountFromLender, data.terms.affiliateCode);

            mapping(address => uint256) storage _feesWithdrawable = feesWithdrawable[data.terms.payableCurrency];
            if (protocolFee > 0) _feesWithdrawable[address(this)] += protocolFee;
            if (affiliateFee > 0) _feesWithdrawable[affiliate] += affiliateFee;
        }

        // Get promissory notes from two parties involved, then burn
        address lender = lenderNote.ownerOf(loanId);
        _burnLoanNotes(loanId);

        // Collateral redistribution
        IERC721(data.terms.collateralAddress).safeTransferFrom(address(this), lender, data.terms.collateralId);

        // Collect claim fee from lender
        _collectIfNonzero(IERC20(data.terms.payableCurrency), lender, _amountFromLender);

        emit LoanClaimed(loanId);
    }

    /**
     * @notice Burn a lender note, for an already-completed loan, in order to receive
     *         held tokens already paid back by the borrower. Can only be called by the
     *         owner of the note.
     *
     * @param loanId                    The ID of the lender note to redeem.
     * @param _amountFromLender         Any redemption fees to be collected from the lender.
     * @param to                        The address to receive the held tokens.
     */
    function redeemNote(
        uint256 loanId,
        uint256 _amountFromLender,
        address to
    ) external override onlyRole(REPAYER_ROLE) nonReentrant {
        NoteReceipt memory receipt = noteReceipts[loanId];
        (address token, uint256 amount) = (receipt.token, receipt.amount);
        if (token == address(0) || amount == 0) revert LC_NoReceipt(loanId);

        // Deduct the redeem fee from the amount and assign for withdrawal
        amount -= _amountFromLender;

        // Assign fees for withdrawal
        (uint256 protocolFee, uint256 affiliateFee, address affiliate) =
            _getAffiliateSplit(_amountFromLender, loans[loanId].terms.affiliateCode);

        mapping(address => uint256) storage _feesWithdrawable = feesWithdrawable[token];
        if (protocolFee > 0) _feesWithdrawable[address(this)] += protocolFee;
        if (affiliateFee > 0) _feesWithdrawable[affiliate] += affiliateFee;

        // Delete the receipt
        delete noteReceipts[loanId];

        // Burn the note
        address lender = lenderNote.ownerOf(loanId);
        lenderNote.burn(loanId);

        // Transfer the held tokens to the lender-specified address
        _transferIfNonzero(IERC20(token), to, amount);

        emit NoteRedeemed(token, lender, to, loanId, amount);
    }

    /**
     * @notice Roll over a loan, atomically closing one and re-opening a new one with the
     *         same collateral. Instead of full repayment, only net payments from each
     *         party are required. Each rolled-over loan is marked as complete, and the new
     *         loan is given a new unique ID and notes. At the time of calling, any needed
     *         net payments have been collected by the RepaymentController for withdrawal.
     *
     * @param oldLoanId             The ID of the old loan.
     * @param borrower              The borrower for the loan.
     * @param lender                The lender for the old loan.
     * @param terms                 The terms of the new loan.
     * @param _settledAmount        The amount LoanCore needs to withdraw to settle.
     * @param _amountToOldLender    The payment to the old lender (if lenders are changing).
     * @param _amountToLender       The payment to the lender (if same as old lender).
     * @param _amountToBorrower     The payment to the borrower (in the case of leftover principal).
     *
     * @return newLoanId            The ID of the new loan.
     */
    function rollover(
        uint256 oldLoanId,
        address borrower,
        address lender,
        LoanLibrary.LoanTerms calldata terms,
        uint256 _settledAmount,
        uint256 _amountToOldLender,
        uint256 _amountToLender,
        uint256 _amountToBorrower
    ) external override whenNotPaused onlyRole(ORIGINATOR_ROLE) nonReentrant returns (uint256 newLoanId) {
        LoanLibrary.LoanData storage data = loans[oldLoanId];
        // Ensure valid loan state for old loan
        if (data.state != LoanLibrary.LoanState.Active) revert LC_InvalidState(data.state);

        // State change for old loan
        data.state = LoanLibrary.LoanState.Repaid;

        address oldLender = lenderNote.ownerOf(oldLoanId);
        IERC20 payableCurrency = IERC20(data.terms.payableCurrency);

        // Check that contract will not net lose tokens
        if (_amountToOldLender + _amountToLender + _amountToBorrower > _settledAmount)
            revert LC_CannotSettle(_amountToOldLender + _amountToLender + _amountToBorrower, _settledAmount);
        {
            // Assign fees for withdrawal
            uint256 feesEarned;
            unchecked { feesEarned = _settledAmount - _amountToOldLender - _amountToLender - _amountToBorrower; }

            // Make sure split goes to affiliate code from _new_ terms
            (uint256 protocolFee, uint256 affiliateFee, address affiliate) =
                _getAffiliateSplit(feesEarned, terms.affiliateCode);

            // Assign fees for withdrawal
            mapping(address => uint256) storage _feesWithdrawable = feesWithdrawable[address(payableCurrency)];
            if (protocolFee > 0) _feesWithdrawable[address(this)] += protocolFee;
            if (affiliateFee > 0) _feesWithdrawable[affiliate] += affiliateFee;
        }

        // Set up new loan
        newLoanId = loanIdTracker.current();
        loanIdTracker.increment();

        loans[newLoanId] = LoanLibrary.LoanData({
            terms: terms,
            state: LoanLibrary.LoanState.Active,
            startDate: uint160(block.timestamp),
            feeSnapshot: data.feeSnapshot
        });

        // Burn old notes
        _burnLoanNotes(oldLoanId);

        // Mint new notes
        _mintLoanNotes(newLoanId, borrower, lender);

        // Perform net settlement operations
        _collectIfNonzero(payableCurrency, msg.sender, _settledAmount);
        _transferIfNonzero(payableCurrency, oldLender, _amountToOldLender);
        _transferIfNonzero(payableCurrency, lender, _amountToLender);
        _transferIfNonzero(payableCurrency, borrower, _amountToBorrower);

        emit LoanRepaid(oldLoanId);
        emit LoanStarted(newLoanId, lender, borrower);
        emit LoanRolledOver(oldLoanId, newLoanId);
    }

    // ======================================== NONCE MANAGEMENT ========================================

    /**
     * @notice Mark a nonce as used in the context of starting a loan. Reverts if
     *         nonce has already been used. Can only be called by Origination Controller.
     *
     * @param user                  The user for whom to consume a nonce.
     * @param nonce                 The nonce to consume.
     */
    function consumeNonce(address user, uint160 nonce) external override whenNotPaused onlyRole(ORIGINATOR_ROLE) {
        _useNonce(user, nonce);
    }

    /**
     * @notice Mark a nonce as used in order to invalidate signatures with the nonce.
     *         Does not allow specifying the user, and automatically consumes the nonce
     *         of the caller.
     *
     * @param nonce                 The nonce to consume.
     */
    function cancelNonce(uint160 nonce) external override {
        _useNonce(msg.sender, nonce);
    }

    // ========================================= VIEW FUNCTIONS =========================================

    /**
     * @notice Returns the LoanData struct for the specified loan ID.
     *
     * @param loanId                The ID of the given loan.
     *
     * @return loanData             The struct containing loan state and terms.
     */
    function getLoan(uint256 loanId) external view override returns (LoanLibrary.LoanData memory loanData) {
        return loans[loanId];
    }

    /**
     * @notice Returns the note receipt data for a given loan ID. Does
     *         not revert, returns 0 if no receipt.
     *
     * @param loanId                The ID of the given loan.
     *
     * @return token                The address of the token for the note.
     * @return amount               The amount of the note.
     */
    function getNoteReceipt(uint256 loanId) external view override returns (address, uint256) {
        NoteReceipt storage receipt = noteReceipts[loanId];
        return (receipt.token, receipt.amount);
    }

    /**
     * @notice Reports if the caller is allowed to call functions on the given vault.
     *         Determined by if they are the borrower for the loan, defined by ownership
     *         of the relevant BorrowerNote.
     *
     * @dev Implemented as part of the ICallDelegator interface.
     *
     * @param caller                The user that wants to call a function.
     * @param vault                 The vault that the caller wants to call a function on.
     *
     * @return allowed              True if the caller is allowed to call on the vault.
     */
    function canCallOn(address caller, address vault) external view override whenNotPaused returns (bool) {
        // if the collateral is not currently being used in a loan, disallow
        if (!collateralInUse[keccak256(abi.encode(OwnableERC721(vault).ownershipToken(), uint256(uint160(vault))))]) {
            return false;
        }

        uint256 noteCount = borrowerNote.balanceOf(caller);
        for (uint256 i = 0; i < noteCount;) {
            uint256 loanId = borrowerNote.tokenOfOwnerByIndex(caller, i);
            LoanLibrary.LoanTerms storage terms = loans[loanId].terms;

            // if the borrower is currently borrowing against this vault,
            // return true
            if (
                terms.collateralAddress == OwnableERC721(vault).ownershipToken() &&
                terms.collateralId == uint256(uint160(vault))
            ) {
                return true;
            }

            // Can never overflow bc balanceOf is bounded by uint256
            unchecked {
                i++;
            }
        }
        return false;
    }

    /**
     * @notice Reports whether the given nonce has been previously used by a user. Returning
     *         false does not mean that the nonce will not clash with another potential off-chain
     *         signature that is stored somewhere.
     *
     * @param user                  The user to check the nonce for.
     * @param nonce                 The nonce to check.
     *
     * @return used                 Whether the nonce has been used.
     */
    function isNonceUsed(address user, uint160 nonce) external view override returns (bool) {
        return usedNonces[user][nonce];
    }

    // ========================================= FEE MANAGEMENT =========================================

    /**
     * @notice Claim any feesWithdrawable balance pending for the caller, as specified by token.
     *         This may accumulate from either affiliate fee shares or borrower forced repayments.
     *
     * @param token                 The contract address of the token to claim tokens for.
     * @param amount                The amount of tokens to claim.
     * @param to                    The address to send the tokens to.
     */
    function withdraw(address token, uint256 amount, address to) external override nonReentrant {
        if (token == address(0)) revert LC_ZeroAddress("token");
        if (amount == 0) revert LC_ZeroAmount();
        if (to == address(0)) revert LC_ZeroAddress("to");

        // any token balances remaining on this contract are fees owned by the protocol
        mapping(address => uint256) storage _feesWithdrawable = feesWithdrawable[token];

        uint256 available = _feesWithdrawable[msg.sender];
        if (amount > available) revert LC_CannotWithdraw(amount, available);

        unchecked { _feesWithdrawable[msg.sender] -= amount; }

        _transferIfNonzero(IERC20(token), to, amount);

        emit FeesWithdrawn(token, msg.sender, to, amount);
    }

    /**
     * @notice Claim the protocol fees for the given token. Any token used as principal
     *         for a loan will have accumulated fees. Must be called by contract owner.
     *
     * @param token                     The contract address of the token to claim fees for.
     * @param to                        The address to send the fees to.
     */
    function withdrawProtocolFees(address token, address to) external override nonReentrant onlyRole(FEE_CLAIMER_ROLE) {
        if (token == address(0)) revert LC_ZeroAddress("token");
        if (to == address(0)) revert LC_ZeroAddress("to");

        // any token balances remaining on this contract are fees owned by the protocol
        mapping(address => uint256) storage _feesWithdrawable = feesWithdrawable[token];
        uint256 amount = _feesWithdrawable[address(this)];
        _feesWithdrawable[address(this)] = 0;

        _transferIfNonzero(IERC20(token), to, amount);

        emit FeesWithdrawn(token, msg.sender, to, amount);
    }

    // ======================================== ADMIN FUNCTIONS =========================================

    /**
     * @notice Set the affiliate fee splits for the batch of affiliate codes. Codes and splits should
     *         be matched index-wise. Can only be called by protocol admin.
     *
     * @param codes                     The affiliate code to set the split for.
     * @param splits                    The splits to set for the given codes.
     */
    function setAffiliateSplits(
        bytes32[] calldata codes,
        AffiliateSplit[] calldata splits
    ) external override onlyRole(AFFILIATE_MANAGER_ROLE) {
        if (codes.length != splits.length) revert LC_ArrayLengthMismatch();

        for (uint256 i = 0; i < codes.length;) {
            if (splits[i].splitBps > MAX_AFFILIATE_SPLIT)
                revert LC_OverMaxSplit(splits[i].splitBps, MAX_AFFILIATE_SPLIT);

            if (affiliateSplits[codes[i]].affiliate != address(0))
                revert LC_AffiliateCodeAlreadySet(codes[i]);

            affiliateSplits[codes[i]] = splits[i];
            emit AffiliateSet(codes[i], splits[i].affiliate, splits[i].splitBps);

            // codes is calldata, overflow is impossible bc of calldata
            // size limits vis-a-vis gas
            unchecked {
                i++;
            }
        }
    }

    /**
     * @notice Shuts down the contract, callable by a designated role. Irreversible.
     *         When the contract is shutdown, loans can only be repaid.
     *         New loans cannot be started, defaults cannot be claimed,
     *         loans cannot be rolled over, and vault utility cannot be
     *         employed. This is an emergency recovery feature.
     */
    function shutdown() external onlyRole(SHUTDOWN_ROLE) {
        _pause();
    }

    // ============================================= HELPERS ============================================


    /**
     * @dev Perform shared logic across repay operations repay and forceRepay - all "checks" and "effects".
     *      Will validate loan state, perform accounting calculations, update storage and burn loan notes.
     *      Transfers should occur in the calling function.
     *
     * @param loanId                The ID of the loan to repay.
     * @param _amountFromPayer      The amount of tokens to be collected from the repayer.
     * @param _amountToLender       The amount of tokens to be distributed to the lender (net after fees).
     *
     * @return data                 The loan data for the repay operation.
     */
    function _handleRepay(
        uint256 loanId,
        uint256 _amountFromPayer,
        uint256 _amountToLender
    ) internal returns (LoanLibrary.LoanData memory data) {
        data = loans[loanId];
        // Ensure valid initial loan state when repaying loan
        if (data.state != LoanLibrary.LoanState.Active) revert LC_InvalidState(data.state);

        // Check that we will not net lose tokens.
        if (_amountToLender > _amountFromPayer) revert LC_CannotSettle(_amountToLender, _amountFromPayer);

        uint256 feesEarned;
        unchecked { feesEarned = _amountFromPayer - _amountToLender; }

        (uint256 protocolFee, uint256 affiliateFee, address affiliate) =
            _getAffiliateSplit(feesEarned, data.terms.affiliateCode);

        // Assign fees for withdrawal
        mapping(address => uint256) storage _feesWithdrawable = feesWithdrawable[data.terms.payableCurrency];
        if (protocolFee > 0) _feesWithdrawable[address(this)] += protocolFee;
        if (affiliateFee > 0) _feesWithdrawable[affiliate] += affiliateFee;

        // State changes and cleanup
        loans[loanId].state = LoanLibrary.LoanState.Repaid;
        collateralInUse[keccak256(abi.encode(data.terms.collateralAddress, data.terms.collateralId))] = false;
    }

    /**
     * @dev Lookup the submitted affiliateCode for a split value, and return the amount
     *      going to protocol and the amount going to the affiliate, along with destination.
     *
     * @param amount                The amount to split.
     * @param affiliateCode         The affiliate code to lookup.
     *
     * @return protocolFee          The amount going to protocol.
     * @return affiliateFee         The amount going to the affiliate.
     * @return affiliate            The address of the affiliate.
     */
    function _getAffiliateSplit(
        uint256 amount,
        bytes32 affiliateCode
    ) internal view returns (uint256 protocolFee, uint256 affiliateFee, address affiliate) {
        AffiliateSplit memory split = affiliateSplits[affiliateCode];

        if (split.affiliate == address(0)) {
            return (amount, 0, address(0));
        }

        affiliate = split.affiliate;
        affiliateFee = amount * split.splitBps / BASIS_POINTS_DENOMINATOR;
        unchecked { protocolFee = amount - affiliateFee; }
    }

    /**
     * @dev Consume a nonce, by marking it as used for that user. Reverts if the nonce
     *      has already been used.
     *
     * @param user                  The user for whom to consume a nonce.
     * @param nonce                 The nonce to consume.
     */
    function _useNonce(address user, uint160 nonce) internal {
        mapping(uint160 => bool) storage _usedNonces = usedNonces[user];

        if (_usedNonces[nonce]) revert LC_NonceUsed(user, nonce);
        // set nonce to used
        _usedNonces[nonce] = true;

        emit NonceUsed(user, nonce);
    }

    /**
     * @dev Mint a borrower and lender note together - easier to make sure
     *      they are synchronized.
     *
     * @param loanId                The token ID to mint.
     * @param borrower              The address of the recipient of the borrower note.
     * @param lender                The address of the recipient of the lender note.
     */
    function _mintLoanNotes(
        uint256 loanId,
        address borrower,
        address lender
    ) internal {
        borrowerNote.mint(borrower, loanId);
        lenderNote.mint(lender, loanId);
    }

    /**
     * @dev Burn a borrower and lender note together - easier to make sure
     *      they are synchronized.
     *
     * @param loanId                The token ID to burn.
     */
    function _burnLoanNotes(uint256 loanId) internal {
        lenderNote.burn(loanId);
        borrowerNote.burn(loanId);
    }

    /**
     * @dev Perform an ERC20 transfer, if the specified amount is nonzero - else no-op.
     *
     * @param token                 The token to transfer.
     * @param to                    The address receiving the tokens.
     * @param amount                The amount of tokens to transfer.
     */
    function _transferIfNonzero(
        IERC20 token,
        address to,
        uint256 amount
    ) internal {
        if (amount > 0) token.safeTransfer(to, amount);
    }

    /**
     * @dev Perform an ERC20 transferFrom, if the specified amount is nonzero - else no-op.
     *
     * @param token                 The token to transfer.
     * @param from                  The address sending the tokens.
     * @param amount                The amount of tokens to transfer.
     */
    function _collectIfNonzero(
        IERC20 token,
        address from,
        uint256 amount
    ) internal {
        if (amount > 0) token.safeTransferFrom(from, address(this), amount);
    }

    /**
     * @dev Blocks the contract from unpausing once paused.
     */
    function _unpause() internal override whenPaused {
        revert LC_Shutdown();
    }
}

// File: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../IERC20.sol";
import "../../../utils/Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// 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/access/AccessControlEnumerable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IAccessControlEnumerable.sol";
import "./AccessControl.sol";
import "../utils/structs/EnumerableSet.sol";

/**
 * @dev Extension of {AccessControl} that allows enumerating the members of each role.
 */
abstract contract AccessControlEnumerable is IAccessControlEnumerable, AccessControl {
    using EnumerableSet for EnumerableSet.AddressSet;

    mapping(bytes32 => EnumerableSet.AddressSet) private _roleMembers;

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

    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) public view override returns (address) {
        return _roleMembers[role].at(index);
    }

    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) public view override returns (uint256) {
        return _roleMembers[role].length();
    }

    /**
     * @dev Overload {grantRole} to track enumerable memberships
     */
    function grantRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        super.grantRole(role, account);
        _roleMembers[role].add(account);
    }

    /**
     * @dev Overload {revokeRole} to track enumerable memberships
     */
    function revokeRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        super.revokeRole(role, account);
        _roleMembers[role].remove(account);
    }

    /**
     * @dev Overload {renounceRole} to track enumerable memberships
     */
    function renounceRole(bytes32 role, address account) public virtual override(AccessControl, IAccessControl) {
        super.renounceRole(role, account);
        _roleMembers[role].remove(account);
    }

    /**
     * @dev Overload {_setupRole} to track enumerable memberships
     */
    function _setupRole(bytes32 role, address account) internal virtual override {
        super._setupRole(role, account);
        _roleMembers[role].add(account);
    }
}

// File: @openzeppelin/contracts/security/Pausable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor() {
        _paused = false;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        require(!paused(), "Pausable: paused");
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        require(paused(), "Pausable: not paused");
        _;
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

// File: @openzeppelin/contracts/security/ReentrancyGuard.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

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

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

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

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

// File: contracts/interfaces/ILoanCore.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

import "../libraries/LoanLibrary.sol";
import "./IPromissoryNote.sol";

interface ILoanCore {

    // ================ Data Types =================

    struct AffiliateSplit {
        address affiliate;
        uint96 splitBps;
    }

    struct NoteReceipt {
        address token;
        uint256 amount;
    }

    // ================ Events =================

    event LoanStarted(uint256 loanId, address lender, address borrower);
    event LoanRepaid(uint256 loanId);
    event ForceRepay(uint256 loanId);
    event LoanRolledOver(uint256 oldLoanId, uint256 newLoanId);
    event LoanClaimed(uint256 loanId);
    event NoteRedeemed(address indexed token, address indexed caller, address indexed to, uint256 tokenId, uint256 amount);
    event NonceUsed(address indexed user, uint160 nonce);

    event FeesWithdrawn(address indexed token, address indexed caller, address indexed to, uint256 amount);
    event AffiliateSet(bytes32 indexed code, address indexed affiliate, uint96 splitBps);

    // ============== Lifecycle Operations ==============

    function startLoan(
        address lender,
        address borrower,
        LoanLibrary.LoanTerms calldata terms,
        uint256 _amountFromLender,
        uint256 _amountToBorrower,
        LoanLibrary.FeeSnapshot calldata feeSnapshot
    ) external returns (uint256 loanId);

    function repay(
        uint256 loanId,
        address payer,
        uint256 _amountFromPayer,
        uint256 _amountToLender
    ) external;

    function forceRepay(
        uint256 loanId,
        address payer,
        uint256 _amountFromPayer,
        uint256 _amountToLender
    ) external;

    function claim(
        uint256 loanId,
        uint256 _amountFromLender
    ) external;

    function redeemNote(
        uint256 loanId,
        uint256 _amountFromLender,
        address to
    ) external;

    function rollover(
        uint256 oldLoanId,
        address borrower,
        address lender,
        LoanLibrary.LoanTerms calldata terms,
        uint256 _settledAmount,
        uint256 _amountToOldLender,
        uint256 _amountToLender,
        uint256 _amountToBorrower
    ) external returns (uint256 newLoanId);

    // ============== Nonce Management ==============

    function consumeNonce(address user, uint160 nonce) external;

    function cancelNonce(uint160 nonce) external;

    // ============== Fee Management ==============

    function withdraw(address token, uint256 amount, address to) external;

    function withdrawProtocolFees(address token, address to) external;

    // ============== Admin Operations ==============

    function setAffiliateSplits(bytes32[] calldata codes, AffiliateSplit[] calldata splits) external;

    // ============== View Functions ==============

    function getLoan(uint256 loanId) external view returns (LoanLibrary.LoanData calldata loanData);

    function getNoteReceipt(uint256 loanId) external view returns (address token, uint256 amount);

    function isNonceUsed(address user, uint160 nonce) external view returns (bool);

    function borrowerNote() external view returns (IPromissoryNote);

    function lenderNote() external view returns (IPromissoryNote);

}

// File: contracts/interfaces/ICallDelegator.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

interface ICallDelegator {
    // ============== View Functions ==============

    function canCallOn(address caller, address vault) external view returns (bool);
}

// File: contracts/interfaces/IPromissoryNote.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol";

import "./INFTWithDescriptor.sol";

interface IPromissoryNote is INFTWithDescriptor, IERC721Enumerable {
    // ============== Token Operations ==============

    function mint(address to, uint256 loanId) external returns (uint256);

    function burn(uint256 tokenId) external;

    // ============== Initializer ==============

    function initialize(address loanCore) external;
}

// File: contracts/PromissoryNote.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/utils/introspection/IERC165.sol";
import "@openzeppelin/contracts/access/AccessControlEnumerable.sol";
import "@openzeppelin/contracts/utils/Counters.sol";

import "./interfaces/IPromissoryNote.sol";
import "./interfaces/ILoanCore.sol";
import "./interfaces/INFTDescriptor.sol";
import "./nft/ERC721Permit.sol";

import {
    PN_ZeroAddress,
    PN_MintingRole,
    PN_BurningRole,
    PN_DoesNotExist
} from "./errors/Lending.sol";

/**
 * @title PromissoryNote
 * @author Non-Fungible Technologies, Inc.
 *
 * Built off Openzeppelin's ERC721Enumerable. Used for
 * representing rights and obligations in the context of a loan - the
 * right to claim collateral for lenders (instantiated as LenderNote),
 * and the right to recover collateral upon repayment for borrowers
 * (instantiated as BorrowerNote).
 *
 * @dev {ERC721} token, including:
 *
 *  - ability for holders to burn (destroy) their tokens
 *  - a minter role that allows for token minting (creation)
 *  - token ID and URI autogeneration
 *
 * This contract uses {AccessControlEnumerable} to lock permissioned functions using the
 * different roles - head to its documentation for details.
 *
 * The account that deploys the contract will be granted the minter and pauser
 * roles, as well as the admin role, which will let it grant both minter
 * and pauser roles to other accounts.
 */
contract PromissoryNote is
    Context,
    AccessControlEnumerable,
    ERC721Enumerable,
    ERC721Permit,
    IPromissoryNote
{
    using Counters for Counters.Counter;

    // ============================================ STATE ==============================================

    // =================== Constants =====================

    /// @dev After loanCore initialization, admin role is permanently revoked.
    bytes32 public constant ADMIN_ROLE = keccak256("ADMIN");
    bytes32 public constant MINT_BURN_ROLE = keccak256("MINT/BURN");
    bytes32 public constant RESOURCE_MANAGER_ROLE = keccak256("RESOURCE_MANAGER");

    // ================= State Variables ==================

    /// @dev Contract for returning tokenURI resources.
    INFTDescriptor public descriptor;

    // ========================================= CONSTRUCTOR ===========================================

    /**
     * @dev Creates the promissory note contract, granting minter, burner
     *      and pauser roles to the specified owner address (which in practice
     *      will be LoanCore).
     *
     * @param name                  The name of the token (see ERC721).
     * @param symbol                The symbol of the token (see ERC721).
     * @param _descriptor           The resource descriptor contract.
     */
    constructor(
        string memory name,
        string memory symbol,
        address _descriptor
    ) ERC721(name, symbol) ERC721Permit(name) {
        if (_descriptor == address(0)) revert PN_ZeroAddress("descriptor");

        descriptor = INFTDescriptor(_descriptor);

        _setupRole(ADMIN_ROLE, msg.sender);
        _setupRole(RESOURCE_MANAGER_ROLE, msg.sender);

        // Allow admin to set mint/burn role, which they will do
        // during initialize. After initialize, admin role is
        // permanently revoked, so mint/burn role becomes immutable
        // and initialize cannot be called again.
        // Do not set role admin for admin role.
        _setRoleAdmin(MINT_BURN_ROLE, ADMIN_ROLE);
        _setRoleAdmin(RESOURCE_MANAGER_ROLE, RESOURCE_MANAGER_ROLE);
    }

    /**
     * @notice Grants mint/burn access to the specified address, which should be an
     *         instance of LoanCore. Once role is set, it is immutable,
     *         and cannot be set again.
     *
     * @param loanCore              The address of the admin.
     */
    function initialize(address loanCore) external onlyRole(ADMIN_ROLE) {
        // Grant mint/burn role to loanCore
        _setupRole(MINT_BURN_ROLE, loanCore);

        // Revoke admin role from msg.sender. Since there is no ROLE_ADMIN,
        // nobody can ever get ADMIN_ROLE again.
        renounceRole(ADMIN_ROLE, msg.sender);
    }

    // ======================================= TOKEN OPERATIONS =========================================

    /**
     * @notice Create a new token and assign it to a specified owner. The token ID
     *         should match the loan ID, and can only be called by the minter. Also
     *         updates the mapping to lookup loan IDs by note IDs.
     *
     * @dev See {ERC721-_safeMint}.
     *
     * @param to                    The owner of the minted token.
     * @param loanId                The ID of the token to mint, should match a loan.
     *
     * @return tokenId              The newly minted token ID.
     */
    function mint(address to, uint256 loanId) external override returns (uint256) {
        if (!hasRole(MINT_BURN_ROLE, msg.sender)) revert PN_MintingRole(msg.sender);

        _safeMint(to, loanId);

        return loanId;
    }

    /**
     * @notice Burn a token assigned to a specified owner. The token ID should match a loan ID,
     *         and can only be called by a burner - in practice LoanCore, which burns notes when
     *         a loan ends.
     *
     * @dev See {ERC721-_burn}.
     *
     * @param tokenId               The ID of the token to burn, should match a loan.
     */
    function burn(uint256 tokenId) external override {
        if (!hasRole(MINT_BURN_ROLE, msg.sender)) revert PN_BurningRole(msg.sender);
        _burn(tokenId);
    }

    // ===================================== ERC721 UTILITIES ============================================

    /**
     * @notice Getter of specific URI for an ERC721 token ID.
     *
     * @param tokenId               The ID of the token to get the URI for.
     *
     * @return                      The token ID's URI.
     */
    function tokenURI(uint256 tokenId) public view override(INFTWithDescriptor, ERC721) returns (string memory) {
        if (!_exists(tokenId)) revert PN_DoesNotExist(tokenId);

        return descriptor.tokenURI(address(this), tokenId);
    }

    /**
     * @notice Changes the descriptor contract for reporting tokenURI
     *         resources. Can only be called by a resource manager.
     *
     * @param _descriptor           The new descriptor contract.
     */
    function setDescriptor(address _descriptor) external onlyRole(RESOURCE_MANAGER_ROLE) {
        if (_descriptor == address(0)) revert PN_ZeroAddress("descriptor");

        descriptor = INFTDescriptor(_descriptor);

        emit SetDescriptor(msg.sender, _descriptor);
    }

    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId)
        public
        view
        virtual
        override(AccessControlEnumerable, ERC721, ERC721Enumerable, IERC165)
        returns (bool)
    {
        return super.supportsInterface(interfaceId);
    }

    /**
     * @dev Hook that is called before any token transfer.
     *      This notifies the promissory note about the ownership transfer.
     *
     * @param from                  The previous owner of the token.
     * @param to                    The owner of the token after transfer.
     * @param tokenId               The token ID.
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 tokenId
    ) internal virtual override(ERC721, ERC721Enumerable) {
        super._beforeTokenTransfer(from, to, tokenId);
    }
}

// File: contracts/libraries/InterestCalculator.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

/**
 * @title InterestCalculator
 * @author Non-Fungible Technologies, Inc.
 *
 * Interface for calculating the interest amount
 * given an interest rate and principal amount. Assumes
 * that the interestRate is already expressed over the desired
 * time period.
 */
abstract contract InterestCalculator {
    // ============================================ STATE ==============================================

    /// @dev The units of precision equal to the minimum interest of 1 basis point.
    uint256 public constant INTEREST_RATE_DENOMINATOR = 1e18;

    uint256 public constant BASIS_POINTS_DENOMINATOR = 1e4;

    // ======================================== CALCULATIONS ===========================================

    /**
     * @notice Calculate the interest due over a full term.
     *
     * @dev Interest and principal must be entered with 18 units of
     *      precision from the basis point unit (e.g. 1e18 == 0.01%)
     *
     * @param principal                             Principal amount in the loan terms.
     * @param proratedInterestRate                  Interest rate in the loan terms, prorated over loan duration.
     *
     * @return interest                             The amount of interest due.
     */
    function getInterestAmount(uint256 principal, uint256 proratedInterestRate) public pure returns (uint256) {
        return principal * proratedInterestRate / (INTEREST_RATE_DENOMINATOR * BASIS_POINTS_DENOMINATOR);
    }
}

// File: contracts/vault/OwnableERC721.sol



// SPDX-License-Identifier: GPL-3.0-only

pragma solidity 0.8.18;

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

import { OERC721_CallerNotOwner } from "../errors/Vault.sol";

/**
 * @title OwnableERC721
 * @author Non-Fungible Technologies, Inc.
 *
 * Uses ERC721 ownership for access control to a set of contracts.
 * Ownership of underlying contract determined by ownership of a token ID,
 * where the token ID converts to an on-chain address.
 */
abstract contract OwnableERC721 {
    event SetOwnershipToken(address indexed caller, address indexed ownershipToken);

    // ============================================ STATE ==============================================

    /// @dev The ERC721 token that contract owners should have ownership of.
    address public ownershipToken;

    // ========================================= VIEW FUNCTIONS =========================================

    /**
     * @notice Specifies the owner of the underlying token ID, derived
     *         from the contract address of the contract implementing.
     *
     * @return ownerAddress         The owner of the underlying token derived from
     *                              the calling address.
     */
    function owner() public view virtual returns (address ownerAddress) {
        return IERC721(ownershipToken).ownerOf(uint256(uint160(address(this))));
    }

    // ============================================ HELPERS =============================================

    /**
     * @dev Set the ownership token - the ERC721 that specified who controls
     *      defined addresses.
     *
     * @param _ownershipToken       The address of the ERC721 token that defines ownership.
     */
    function _setNFT(address _ownershipToken) internal {
        ownershipToken = _ownershipToken;

        emit SetOwnershipToken(msg.sender, _ownershipToken);
    }

    /**
     * @dev Similar to Ownable - checks the method is being called by the owner,
     *      where the owner is defined by the token ID in the ownership token which
     *      maps to the calling contract address.
     */
    modifier onlyOwner() {
        if (owner() != msg.sender) revert OERC721_CallerNotOwner(msg.sender);
        _;
    }
}

// File: contracts/errors/Lending.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

import "../libraries/LoanLibrary.sol";

/**
 * @title LendingErrors
 * @author Non-Fungible Technologies, Inc.
 *
 * This file contains custom errors for the core lending protocol contracts, with errors
 * prefixed by the contract that throws them (e.g., "OC_" for OriginationController).
 * Errors located in one place to make it possible to holistically look at all
 * protocol failure cases.
 */

// ==================================== ORIGINATION CONTROLLER ======================================
/// @notice All errors prefixed with OC_, to separate from other contracts in the protocol.

/**
 * @notice Zero address passed in where not allowed.
 *
 * @param addressType                  The name of the parameter for which a zero address was provided.
 */
error OC_ZeroAddress(string addressType);

/**
 * @notice Ensure valid loan state for loan lifceycle operations.
 *
 * @param state                         Current state of a loan according to LoanState enum.
 */
error OC_InvalidState(LoanLibrary.LoanState state);

/**
 * @notice Loan duration must be greater than 1hr and less than 3yrs.
 *
 * @param durationSecs                 Total amount of time in seconds.
 */
error OC_LoanDuration(uint256 durationSecs);

/**
 * @notice Interest must be greater than 0.01% and less than 10,000%. (interestRate / 1e18 >= 1)
 *
 * @param interestRate                  InterestRate with 1e18 multiplier.
 */
error OC_InterestRate(uint256 interestRate);

/**
 * @notice One of the predicates for item verification failed.
 *
 * @param borrower                      The address of the borrower.
 * @param lender                        The address of the lender.
 * @param verifier                      The address of the verifier contract.
 * @param collateralAddress             The address of the collateral token.
 * @param collateralId                  The token ID of the collateral.
 * @param data                          The verification data (to be parsed by verifier).
 */
error OC_PredicateFailed(
    address borrower,
    address lender,
    address verifier,
    address collateralAddress,
    uint256 collateralId,
    bytes data
);

/**
 * @notice The predicates array is empty.
 */
error OC_PredicatesArrayEmpty();

/**
 * @notice A caller attempted to approve themselves.
 *
 * @param caller                        The caller of the approve function.
 */
error OC_SelfApprove(address caller);

/**
 * @notice A caller attempted to originate a loan with their own signature.
 *
 * @param caller                        The caller of the approve function, who was also the signer.
 */
error OC_ApprovedOwnLoan(address caller);

/**
 * @notice The signature could not be recovered to the counterparty or approved party.
 *
 * @param target                        The target party of the signature, which should either be the signer,
 *                                      or someone who has approved the signer.
 * @param signer                        The signer determined from ECDSA.recover.
 */
error OC_InvalidSignature(address target, address signer);

/**
 * @notice The verifier contract specified in a predicate has not been whitelisted.
 *
 * @param verifier                      The verifier the caller attempted to use.
 */
error OC_InvalidVerifier(address verifier);

/**
 * @notice The function caller was neither borrower or lender, and was not approved by either.
 *
 * @param caller                        The unapproved function caller.
 */
error OC_CallerNotParticipant(address caller);

/**
 * @notice Signer is attempting to take the wrong side of the loan.
 *
 * @param signer                       The address of the external signer.
 */
error OC_SideMismatch(address signer);

/**
 * @notice Two related parameters for batch operations did not match in length.
 */
error OC_BatchLengthMismatch();

/**
 * @notice Principal must be greater than 9999 Wei.
 *
 * @param principal                     Principal in ether.
 */
error OC_PrincipalTooLow(uint256 principal);

/**
 * @notice Signature must not be expired.
 *
 * @param deadline                      Deadline in seconds.
 */
error OC_SignatureIsExpired(uint256 deadline);

/**
 * @notice New currency does not match for a loan rollover request.
 *
 * @param oldCurrency                   The currency of the active loan.
 * @param newCurrency                   The currency of the new loan.
 */
error OC_RolloverCurrencyMismatch(address oldCurrency, address newCurrency);

/**
 * @notice New currency does not match for a loan rollover request.
 *
 * @param oldCollateralAddress          The address of the active loan's collateral.
 * @param newCollateralAddress          The token ID of the active loan's collateral.
 * @param oldCollateralId               The address of the new loan's collateral.
 * @param newCollateralId               The token ID of the new loan's collateral.
 */
error OC_RolloverCollateralMismatch(
    address oldCollateralAddress,
    uint256 oldCollateralId,
    address newCollateralAddress,
    uint256 newCollateralId
);

/**
 * @notice Provided payable currency address is not approved for lending.
 *
 * @param payableCurrency       ERC20 token address supplied in loan terms.
 */
error OC_InvalidCurrency(address payableCurrency);

/**
 * @notice Provided collateral address is not approved for lending.
 *
 * @param collateralAddress       ERC721 or ERC1155 token address supplied in loan terms.
 */
error OC_InvalidCollateral(address collateralAddress);

/**
 * @notice Provided token array does not hold any token addresses.
 */
error OC_ZeroArrayElements();

/**
 * @notice Provided token array holds more than 50 token addresses.
 */
error OC_ArrayTooManyElements();

// ==================================== ITEMS VERIFIER ======================================
/// @notice All errors prefixed with IV_, to separate from other contracts in the protocol.

/**
 * @notice The predicate payload was decoded successfully, but list of predicates is empty.
 */
error IV_NoPredicates();

/**
 * @notice Provided SignatureItem is missing an address.
 */
error IV_ItemMissingAddress();

/**
 * @notice Provided SignatureItem has an invalid collateral type.
 * @dev    Should never actually fire, since cType is defined by an enum, so will fail on decode.
 *
 * @param asset                        The NFT contract being checked.
 * @param cType                        The collateralTytpe provided.
 */
error IV_InvalidCollateralType(address asset, uint256 cType);

/**
 * @notice Provided signature item with no required amount. For single ERC721s, specify 1.
 *
 * @param asset                         The NFT contract being checked.
 * @param amount                        The amount provided (should be 0).
 */
error IV_NoAmount(address asset, uint256 amount);

/**
 * @notice Provided a wildcard for a non-ERC721.
 *
 * @param asset                         The NFT contract being checked.
 */
error IV_InvalidWildcard(address asset);

/**
 * @notice The provided token ID is out of bounds for the given collection.
 *
 * @param tokenId                       The token ID provided.
 */
error IV_InvalidTokenId(int256 tokenId);

/**
 * @notice The provided project ID does not exist on the target contract. Only
 *         used for ArtBlocks.
 *
 * @param projectId                     The project ID provided.
 * @param nextProjectId                 The contract's reported nextProjectId.
 */
error IV_InvalidProjectId(uint256 projectId, uint256 nextProjectId);

/**
 * @notice The provided collateralId converts to a vault, but
 *         the vault's address does not convert back to the provided collateralId
 *         when casted to a uint256.
 */
error IV_InvalidCollateralId(uint256 collateralId);

// ==================================== REPAYMENT CONTROLLER ======================================
/// @notice All errors prefixed with RC_, to separate from other contracts in the protocol.

/**
 * @notice Zero address passed in where not allowed.
 *
 * @param addressType                  The name of the parameter for which a zero address was provided.
 */
error RC_ZeroAddress(string addressType);

/**
 * @notice Could not dereference loan from loan ID.
 *
 * @param target                     The loanId being checked.
 */
error RC_CannotDereference(uint256 target);

/**
 * @notice Ensure valid loan state for loan lifceycle operations.
 *
 * @param state                         Current state of a loan according to LoanState enum.
 */
error RC_InvalidState(LoanLibrary.LoanState state);

/**
 * @notice Caller is not the owner of lender note.
 *
 * @param lender                     The owner of the lender note.
 * @param caller                     Msg.sender of the function call.
 */
error RC_OnlyLender(address lender, address caller);

// ==================================== Loan Core ======================================
/// @notice All errors prefixed with LC_, to separate from other contracts in the protocol.

/**
 * @notice Zero address passed in where not allowed.
 *
 * @param addressType                  The name of the parameter for which a zero address was provided.
 */
error LC_ZeroAddress(string addressType);

/// @notice Borrower address is same as lender address.
error LC_ReusedNote();

/// @notice Zero amount passed in where not allowed.
error LC_ZeroAmount();

/**
 * @notice Check collateral is not already used in a active loan.
 *
 * @param collateralAddress             Address of the collateral.
 * @param collateralId                  ID of the collateral token.
 */
error LC_CollateralInUse(address collateralAddress, uint256 collateralId);

/**
 * @notice The reported settlements are invalid, and LoanCore would lose tokens
 *         attempting to perform the requested operations.
 *
 *
 * @param payout                        Amount of tokens to be paid out.
 * @param collected                     Amount of tokens to collect - should be fewer than payout.
 */
error LC_CannotSettle(uint256 payout, uint256 collected);

/**
 * @notice User attempted to withdraw a pending balance that was in excess
 *         of what is available.
 *
 * @param amount                        Amount of tokens to be withdrawn.
 * @param available                     Amount of tokens available to withdraw.
 */
error LC_CannotWithdraw(uint256 amount, uint256 available);

/**
 * @notice Two arrays were provided that must be of matching length, but were not.
 *
 */
error LC_ArrayLengthMismatch();

/**
 * @notice A proposed affiliate split was submitted that is over the maximum.
 *
 * @param splitBps                     The proposed affiliate split.
 * @param maxSplitBps                  The maximum allowed affiliate split.
 *
 */
error LC_OverMaxSplit(uint96 splitBps, uint96 maxSplitBps);

/**
 * @notice Ensure valid loan state for loan lifceycle operations.
 *
 * @param state                         Current state of a loan according to LoanState enum.
 */
error LC_InvalidState(LoanLibrary.LoanState state);

/**
 * @notice Loan duration has not expired.
 *
 * @param dueDate                       Timestamp of the end of the loan duration.
 */
error LC_NotExpired(uint256 dueDate);

/**
 * @notice User address and the specified nonce have already been used.
 *
 * @param user                          Address of collateral owner.
 * @param nonce                         Represents the number of transactions sent by address.
 */
error LC_NonceUsed(address user, uint160 nonce);

/**
 * @notice Protocol attempted to set an affiliate code which already exists. Affiliate
 *         codes are immutable.
 *
 * @param affiliateCode                 The affiliate code being set.
 */
error LC_AffiliateCodeAlreadySet(bytes32 affiliateCode);

/**
 * @notice Specified note token ID does not have a redeemable receipt.
 *
 * @param loanId                     The loanId being checked.
 */
error LC_NoReceipt(uint256 loanId);

/**
 * @notice Only Loan Core contract can call this function.
 */
error LC_CallerNotLoanCore();

/**
 * @notice The loan core contract has been irreversibly shut down.
 */
error LC_Shutdown();

// ==================================== Promissory Note ======================================
/// @notice All errors prefixed with PN_, to separate from other contracts in the protocol.

/**
 * @notice Zero address passed in where not allowed.
 *
 * @param addressType                  The name of the parameter for which a zero address was provided.
 */
error PN_ZeroAddress(string addressType);

/**
 * @notice Caller of mint function must have the MINTER_ROLE in AccessControl.
 *
 * @param caller                        Address of the function caller.
 */
error PN_MintingRole(address caller);

/**
 * @notice Caller of burn function must have the BURNER_ROLE in AccessControl.
 *
 * @param caller                        Address of the function caller.
 */
error PN_BurningRole(address caller);

/**
 * @notice Non-existant token id provided as argument.
 *
 * @param tokenId                       The ID of the token to lookup the URI for.
 */
error PN_DoesNotExist(uint256 tokenId);

// ==================================== Fee Controller ======================================
/// @notice All errors prefixed with FC_, to separate from other contracts in the protocol.

/**
 * @notice Caller attempted to set a lending fee which is larger than the global maximum.
 */
error FC_LendingFeeOverMax(bytes32 selector, uint256 fee, uint256 maxFee);

/**
 * @notice Caller attempted to set a vault mint fee which is larger than the global maximum.
 */
error FC_VaultMintFeeOverMax(uint256 fee, uint256 maxFee);

// ==================================== ERC721 Permit ======================================
/// @notice All errors prefixed with ERC721P_, to separate from other contracts in the protocol.

/**
 * @notice Deadline for the permit has expired.
 *
 * @param deadline                      Permit deadline parameter as a timestamp.
 */
error ERC721P_DeadlineExpired(uint256 deadline);

/**
 * @notice Address of the owner to also be the owner of the tokenId.
 *
 * @param owner                        Owner parameter for the function call.
 */
error ERC721P_NotTokenOwner(address owner);

/**
 * @notice Invalid signature.
 *
 * @param signer                        Signer recovered from ECDSA sugnature hash.
 */
error ERC721P_InvalidSignature(address signer);



// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

// File: @openzeppelin/contracts/utils/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/access/IAccessControlEnumerable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IAccessControl.sol";

/**
 * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
 */
interface IAccessControlEnumerable is IAccessControl {
    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) external view returns (address);

    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) external view returns (uint256);
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IAccessControl.sol";
import "../utils/Context.sol";
import "../utils/Strings.sol";
import "../utils/introspection/ERC165.sol";

/**
 * @dev Contract module that allows children to implement role-based access
 * control mechanisms. This is a lightweight version that doesn't allow enumerating role
 * members except through off-chain means by accessing the contract event logs. Some
 * applications may benefit from on-chain enumerability, for those cases see
 * {AccessControlEnumerable}.
 *
 * Roles are referred to by their `bytes32` identifier. These should be exposed
 * in the external API and be unique. The best way to achieve this is by
 * using `public constant` hash digests:
 *
 * ```
 * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
 * ```
 *
 * Roles can be used to represent a set of permissions. To restrict access to a
 * function call, use {hasRole}:
 *
 * ```
 * function foo() public {
 *     require(hasRole(MY_ROLE, msg.sender));
 *     ...
 * }
 * ```
 *
 * Roles can be granted and revoked dynamically via the {grantRole} and
 * {revokeRole} functions. Each role has an associated admin role, and only
 * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
 *
 * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
 * that only accounts with this role will be able to grant or revoke other
 * roles. More complex role relationships can be created by using
 * {_setRoleAdmin}.
 *
 * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
 * grant and revoke this role. Extra precautions should be taken to secure
 * accounts that have been granted it.
 */
abstract contract AccessControl is Context, IAccessControl, ERC165 {
    struct RoleData {
        mapping(address => bool) members;
        bytes32 adminRole;
    }

    mapping(bytes32 => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /**
     * @dev Modifier that checks that an account has a specific role. Reverts
     * with a standardized message including the required role.
     *
     * The format of the revert reason is given by the following regular expression:
     *
     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
     *
     * _Available since v4.1._
     */
    modifier onlyRole(bytes32 role) {
        _checkRole(role, _msgSender());
        _;
    }

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

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) public view override returns (bool) {
        return _roles[role].members[account];
    }

    /**
     * @dev Revert with a standard message if `account` is missing `role`.
     *
     * The format of the revert reason is given by the following regular expression:
     *
     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
     */
    function _checkRole(bytes32 role, address account) internal view {
        if (!hasRole(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "AccessControl: account ",
                        Strings.toHexString(uint160(account), 20),
                        " is missing role ",
                        Strings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) public view override returns (bytes32) {
        return _roles[role].adminRole;
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
        _grantRole(role, account);
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
        _revokeRole(role, account);
    }

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) public virtual override {
        require(account == _msgSender(), "AccessControl: can only renounce roles for self");

        _revokeRole(role, account);
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event. Note that unlike {grantRole}, this function doesn't perform any
     * checks on the calling account.
     *
     * [WARNING]
     * ====
     * This function should only be called from the constructor when setting
     * up the initial roles for the system.
     *
     * Using this function in any other way is effectively circumventing the admin
     * system imposed by {AccessControl}.
     * ====
     */
    function _setupRole(bytes32 role, address account) internal virtual {
        _grantRole(role, account);
    }

    /**
     * @dev Sets `adminRole` as ``role``'s admin role.
     *
     * Emits a {RoleAdminChanged} event.
     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = getRoleAdmin(role);
        _roles[role].adminRole = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }

    function _grantRole(bytes32 role, address account) private {
        if (!hasRole(role, account)) {
            _roles[role].members[account] = true;
            emit RoleGranted(role, account, _msgSender());
        }
    }

    function _revokeRole(bytes32 role, address account) private {
        if (hasRole(role, account)) {
            _roles[role].members[account] = false;
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

// File: @openzeppelin/contracts/utils/structs/EnumerableSet.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
 * and `uint256` (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;
        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping(bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

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

        if (valueIndex != 0) {
            // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            if (lastIndex != toDeleteIndex) {
                bytes32 lastvalue = set._values[lastIndex];

                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastvalue;
                // Update the index for the moved value
                set._indexes[lastvalue] = valueIndex; // Replace lastvalue's index to valueIndex
            }

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

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

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        return set._values[index];
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function _values(Set storage set) private view returns (bytes32[] memory) {
        return set._values;
    }

    // Bytes32Set

    struct Bytes32Set {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _add(set._inner, value);
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
        return _remove(set._inner, value);
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
        return _contains(set._inner, value);
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(Bytes32Set storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
        return _at(set._inner, index);
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
        return _values(set._inner);
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(uint160(value))));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(uint160(value))));
    }

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

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint160(uint256(_at(set._inner, index))));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(AddressSet storage set) internal view returns (address[] memory) {
        bytes32[] memory store = _values(set._inner);
        address[] memory result;

        assembly {
            result := store
        }

        return result;
    }

    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

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

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

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

    /**
     * @dev Returns the value stored at position `index` in the set. O(1).
     *
     * Note that there are no guarantees on the ordering of values inside the
     * array, and it may change when more values are added or removed.
     *
     * Requirements:
     *
     * - `index` must be strictly less than {length}.
     */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }

    /**
     * @dev Return the entire set in an array
     *
     * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
     * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
     * this function has an unbounded cost, and using it as part of a state-changing function may render the function
     * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
     */
    function values(UintSet storage set) internal view returns (uint256[] memory) {
        bytes32[] memory store = _values(set._inner);
        uint256[] memory result;

        assembly {
            result := store
        }

        return result;
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev External interface of AccessControl declared to support ERC165 detection.
 */
interface IAccessControl {
    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {AccessControl-_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) external view returns (bool);

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {AccessControl-_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) external;

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) external;
}

// 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/Strings.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

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

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

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

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

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

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IERC165.sol";

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

// File: contracts/libraries/LoanLibrary.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

/**
 * @title LoanLibrary
 * @author Non-Fungible Technologies, Inc.
 *
 * Contains all data types used across Arcade lending contracts.
 */
library LoanLibrary {
    /**
     * @dev Enum describing the current state of a loan.
     * State change flow:
     * Created -> Active -> Repaid
     *                   -> Defaulted
     */
    enum LoanState {
        // We need a default that is not 'Created' - this is the zero value
        DUMMY_DO_NOT_USE,
        // The loan has been initialized, funds have been delivered to the borrower and the collateral is held.
        Active,
        // The loan has been repaid, and the collateral has been returned to the borrower. This is a terminal state.
        Repaid,
        // The loan was delinquent and collateral claimed by the lender. This is a terminal state.
        Defaulted
    }

    /**
     * @dev The raw terms of a loan.
     */
    struct LoanTerms {
        // Interest expressed as a rate, unlike V1 gross value.
        // Input conversion: 0.01% = (1 * 10**18) ,  10.00% = (1000 * 10**18)
        // This represents the rate over the lifetime of the loan, not APR.
        // 0.01% is the minimum interest rate allowed by the protocol.
        uint256 proratedInterestRate;
        /// @dev Full-slot variables
        // The amount of principal in terms of the payableCurrency.
        uint256 principal;
        // The token ID of the address holding the collateral.
        /// @dev Can be an AssetVault, or the NFT contract for unbundled collateral
        address collateralAddress;
        /// @dev Packed variables
        // The number of seconds representing relative due date of the loan.
        /// @dev Max is 94,608,000, fits in 96 bits
        uint96 durationSecs;
        // The token ID of the collateral.
        uint256 collateralId;
        // The payable currency for the loan principal and interest.
        address payableCurrency;
        // Timestamp for when signature for terms expires
        uint96 deadline;
        // Affiliate code used to start the loan.
        bytes32 affiliateCode;
    }

    /**
     * @dev Modification of loan terms, used for signing only.
     *      Instead of a collateralId, a list of predicates
     *      is defined by 'bytes' in items.
     */
    struct LoanTermsWithItems {
        // Interest expressed as a rate, unlike V1 gross value.
        // Input conversion: 0.01% = (1 * 10**18) ,  10.00% = (1000 * 10**18)
        // This represents the rate over the lifetime of the loan, not APR.
        // 0.01% is the minimum interest rate allowed by the protocol.
        uint256 proratedInterestRate;
        /// @dev Full-slot variables
        // The amount of principal in terms of the payableCurrency.
        uint256 principal;
        // The tokenID of the address holding the collateral
        address collateralAddress;
        /// @dev Packed variables
        // The number of seconds representing relative due date of the loan.
        /// @dev Max is 94,608,000, fits in 96 bits
        uint96 durationSecs;
        // An encoded list of predicates, along with their verifiers.
        bytes items;
        // The payable currency for the loan principal and interest.
        address payableCurrency;
        // Timestamp for when signature for terms expires
        uint96 deadline;
        // Affiliate code used to start the loan.
        bytes32 affiliateCode;
    }

    /**
     * @dev Predicate for item-based verifications
     */
    struct Predicate {
        // The encoded predicate, to decoded and parsed by the verifier contract.
        bytes data;
        // The verifier contract.
        address verifier;
    }

    /**
     * @dev Snapshot of lending fees at the time of loan creation.
     */
    struct FeeSnapshot {
        // The fee taken when lender claims defaulted collateral.
        uint16 lenderDefaultFee;
        // The fee taken from the borrower's interest repayment.
        uint16 lenderInterestFee;
        // The fee taken from the borrower's principal repayment.
        uint16 lenderPrincipalFee;
    }

    /**
     * @dev The data of a loan. This is stored once the loan is Active
     */
    struct LoanData {
        /// @dev Packed variables
        // The current state of the loan.
        LoanState state;
        // Start date of the loan, using block.timestamp.
        uint160 startDate;
        /// @dev Full-slot variables
        // The raw terms of the loan.
        LoanTerms terms;
        // Record of lending fees at the time of loan creation.
        FeeSnapshot feeSnapshot;
    }
}

// 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: contracts/interfaces/INFTWithDescriptor.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

interface INFTWithDescriptor {
    // ============= Events ==============

    event SetDescriptor(address indexed caller, address indexed descriptor);

    // ================ Resource Metadata ================

    function tokenURI(uint256 tokenId) external view returns (string memory);

    function setDescriptor(address descriptor) external;
}

// 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: contracts/interfaces/INFTDescriptor.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

interface INFTDescriptor {
    function tokenURI(address token, uint256 tokenId) external view returns (string memory);
}
// File: contracts/nft/ERC721Permit.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/utils/cryptography/draft-EIP712.sol";
import "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
import "@openzeppelin/contracts/utils/Counters.sol";

import "../interfaces/IERC721Permit.sol";

import {
    ERC721P_DeadlineExpired,
    ERC721P_NotTokenOwner,
    ERC721P_InvalidSignature
} from "../errors/Lending.sol";

/**
 * @title ERC721Permit
 * @author Non-Fungible Technologies, Inc.
 *
 * @dev Implementation of the ERC721 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * See https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/draft-EIP712.sol
 *
 * Adds the {permit} method, which can be used to change an account's ERC721 allowance (see {IERC721-allowance}) by
 * presenting a message signed by the account. By not relying on `{IERC721-approve}`, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * _Available since v3.4._
 */
abstract contract ERC721Permit is ERC721, IERC721Permit, EIP712 {
    using Counters for Counters.Counter;

    // ============================================ STATE ==============================================

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private immutable _PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 tokenId,uint256 nonce,uint256 deadline)");

    /// @dev Nonce for permit signatures.
    mapping(address => Counters.Counter) private _nonces;

    // ========================================== CONSTRUCTOR ===========================================

    /**
     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
     *
     * It's a good idea to use the same `name` that is defined as the ERC721 token name.
     *
     * @param name                  The name of the signing domain.
     */
    constructor(string memory name) EIP712(name, "1") {}

    // ===================================== PERMIT FUNCTIONALITY =======================================

    /**
     * @notice Allows the spender to spend the token ID which is owned by owner,
     * given owner's signed approval.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `owner` must be the owner of `tokenId`.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     *
     * @param owner                 The owner of the token being permitted.
     * @param spender               The address allowed to spend the token.
     * @param tokenId               The token ID of the given asset.
     * @param deadline              The maximum timestamp the signature is valid for.
     * @param v                     Component of the signature.
     * @param r                     Component of the signature.
     * @param s                     Component of the signature.
     */
    function permit(
        address owner,
        address spender,
        uint256 tokenId,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual override {
        if (block.timestamp > deadline) revert ERC721P_DeadlineExpired(deadline);

        address tokenOwner = ownerOf(tokenId);
        if (owner != tokenOwner && !isApprovedForAll(tokenOwner, owner)) revert ERC721P_NotTokenOwner(owner);

        bytes32 structHash = keccak256(
            abi.encode(_PERMIT_TYPEHASH, owner, spender, tokenId, _useNonce(owner), deadline)
        );

        bytes32 hash = _hashTypedDataV4(structHash);

        address signer = ECDSA.recover(hash, v, r, s);
        if (signer != owner) revert ERC721P_InvalidSignature(signer);

        _approve(spender, tokenId);
    }

    /**
     * @notice Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated.
     *
     * Every successful call to permit increases the owner's nonce by one. This
     * prevents a signature from being used multiple times.
     *
     * @param owner                 The given owner to check the nonce for.
     *
     * @return current              The current nonce for the owner.
     */
    function nonces(address owner) public view virtual override returns (uint256) {
        return _nonces[owner].current();
    }

    /**
     * @notice Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     *
     * @return separator             The bytes for the domain separator.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view override returns (bytes32) {
        return _domainSeparatorV4();
    }

    /**
     * @dev Consumes the nonce - returns the current value and increments.
     *
     * @param owner                 The address of the user to consume a nonce for.
     *
     * @return current              The current nonce, before incrementation.
     */
    function _useNonce(address owner) internal virtual returns (uint256 current) {
        Counters.Counter storage nonce = _nonces[owner];
        current = nonce.current();
        nonce.increment();
    }
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/Strings.sol";
import "../../utils/introspection/ERC165.sol";

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

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        _approve(to, tokenId);
    }

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

        return _tokenApprovals[tokenId];
    }

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

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

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

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

        _transfer(from, to, tokenId);
    }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        _beforeTokenTransfer(from, to, tokenId);

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

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

        emit Transfer(from, to, tokenId);
    }

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

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

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

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
interface IERC721Receiver {
    /**
     * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
     * by `operator` from `from`, this function is called.
     *
     * It must return its Solidity selector to confirm the token transfer.
     * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
     *
     * The selector can be obtained in Solidity with `IERC721.onERC721Received.selector`.
     */
    function onERC721Received(
        address operator,
        address from,
        uint256 tokenId,
        bytes calldata data
    ) external returns (bytes4);
}

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



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../IERC721.sol";

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

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

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

// File: @openzeppelin/contracts/utils/cryptography/draft-EIP712.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./ECDSA.sol";

/**
 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
 *
 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
 * they need in their contracts using a combination of `abi.encode` and `keccak256`.
 *
 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
 * ({_hashTypedDataV4}).
 *
 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
 * the chain id to protect against replay attacks on an eventual fork of the chain.
 *
 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
 *
 * _Available since v3.4._
 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
    uint256 private immutable _CACHED_CHAIN_ID;

    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;

    /* solhint-enable var-name-mixedcase */

    /**
     * @dev Initializes the domain separator and parameter caches.
     *
     * The meaning of `name` and `version` is specified in
     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
     *
     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
     * - `version`: the current major version of the signing domain.
     *
     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
     * contract upgrade].
     */
    constructor(string memory name, string memory version) {
        bytes32 hashedName = keccak256(bytes(name));
        bytes32 hashedVersion = keccak256(bytes(version));
        bytes32 typeHash = keccak256(
            "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
        );
        _HASHED_NAME = hashedName;
        _HASHED_VERSION = hashedVersion;
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
        _TYPE_HASH = typeHash;
    }

    /**
     * @dev Returns the domain separator for the current chain.
     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
        }
    }

    function _buildDomainSeparator(
        bytes32 typeHash,
        bytes32 nameHash,
        bytes32 versionHash
    ) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
    }

    /**
     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
     * function returns the hash of the fully encoded EIP712 message for this domain.
     *
     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
     *
     * ```solidity
     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
     *     keccak256("Mail(address to,string contents)"),
     *     mailTo,
     *     keccak256(bytes(mailContents))
     * )));
     * address signer = ECDSA.recover(digest, signature);
     * ```
     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
    }
}

// File: @openzeppelin/contracts/utils/cryptography/ECDSA.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
 *
 * These functions can be used to verify that a message was signed by the holder
 * of the private keys of a given address.
 */
library ECDSA {
    enum RecoverError {
        NoError,
        InvalidSignature,
        InvalidSignatureLength,
        InvalidSignatureS,
        InvalidSignatureV
    }

    function _throwError(RecoverError error) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert("ECDSA: invalid signature");
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert("ECDSA: invalid signature length");
        } else if (error == RecoverError.InvalidSignatureS) {
            revert("ECDSA: invalid signature 's' value");
        } else if (error == RecoverError.InvalidSignatureV) {
            revert("ECDSA: invalid signature 'v' value");
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature` or error string. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     *
     * Documentation for signature generation:
     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
     *
     * _Available since v4.3._
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        // Check the signature length
        // - case 65: r,s,v signature (standard)
        // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else if (signature.length == 64) {
            bytes32 r;
            bytes32 vs;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            assembly {
                r := mload(add(signature, 0x20))
                vs := mload(add(signature, 0x40))
            }
            return tryRecover(hash, r, vs);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, signature);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
     *
     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
     *
     * _Available since v4.3._
     */
    function tryRecover(
        bytes32 hash,
        bytes32 r,
        bytes32 vs
    ) internal pure returns (address, RecoverError) {
        bytes32 s;
        uint8 v;
        assembly {
            s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
            v := add(shr(255, vs), 27)
        }
        return tryRecover(hash, v, r, s);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
     *
     * _Available since v4.2._
     */
    function recover(
        bytes32 hash,
        bytes32 r,
        bytes32 vs
    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, r, vs);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
     * `r` and `s` signature fields separately.
     *
     * _Available since v4.3._
     */
    function tryRecover(
        bytes32 hash,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address, RecoverError) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return (address(0), RecoverError.InvalidSignatureS);
        }
        if (v != 27 && v != 28) {
            return (address(0), RecoverError.InvalidSignatureV);
        }

        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            return (address(0), RecoverError.InvalidSignature);
        }

        return (signer, RecoverError.NoError);
    }

    /**
     * @dev Overload of {ECDSA-recover} that receives the `v`,
     * `r` and `s` signature fields separately.
     */
    function recover(
        bytes32 hash,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
        _throwError(error);
        return recovered;
    }

    /**
     * @dev Returns an Ethereum Signed Message, created from a `hash`. This
     * produces hash corresponding to the one signed with the
     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
     * JSON-RPC method as part of EIP-191.
     *
     * See {recover}.
     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
    }

    /**
     * @dev Returns an Ethereum Signed Typed Data, created from a
     * `domainSeparator` and a `structHash`. This produces hash corresponding
     * to the one signed with the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
     * JSON-RPC method as part of EIP-712.
     *
     * See {recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
    }
}

// File: contracts/interfaces/IERC721Permit.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

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

interface IERC721Permit is IERC721 {
    // ================ Permit Functionality ================

    function permit(
        address owner,
        address spender,
        uint256 tokenId,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    // ================ View Functions ================

    function nonces(address owner) external view returns (uint256);

    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// File: contracts/errors/Vault.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

/**
 * @title VaultErrors
 * @author Non-Fungible Technologies, Inc.
 *
 * This file contains all custom errors for vault contracts used by the protocol.
 * All errors prefixed by the contract that throws them (e.g., "AV_" for Asset Vault).
 * Errors located in one place to make it possible to holistically look at all
 * asset vault failure cases.
 */

// ==================================== Asset Vault ======================================
/// @notice All errors prefixed with AV_, to separate from other contracts in the protocol.

/**
 * @notice Vault withdraws must be enabled.
 */
error AV_WithdrawsDisabled();

/**
 * @notice Vault withdraws enabled.
 */
error AV_WithdrawsEnabled();

/**
 * @notice Asset vault already initialized.
 *
 * @param ownershipToken                    Caller of initialize function in asset vault contract.
 */
error AV_AlreadyInitialized(address ownershipToken);

/**
 * @notice CanCallOn authorization returned false.
 *
 * @param caller                             Msg.sender of the function call.
 */
error AV_MissingAuthorization(address caller);

/**
 * @notice Call disallowed.
 *
 * @param to                                The contract address to call.
 * @param data                              The data to call the contract with.
 */
error AV_NonWhitelistedCall(address to, bytes4 data);

/**
 * @notice Approval disallowed.
 *
 * @param token                             The token to approve.
 * @param spender                           The spender to approve.
 */
error AV_NonWhitelistedApproval(address token, address spender);

/**
 * @notice Cannot withdraw more than 25 items from a vault at a time.
 *
 * @param arrayLength                  Total elements provided.
 */
error AV_TooManyItems(uint256 arrayLength);

/**
 * @notice The length of either the tokenIds or tokenTypes array does not match
 *         the length of the tokenAddress array.
 *
 * @param arrayType                    Array type that does not match tokenAddress array length.
 */
error AV_LengthMismatch(string arrayType);

/**
 * @notice Zero address passed in where not allowed.
 *
 * @param addressType                  The name of the parameter for which a zero address was provided.
 */
error AV_ZeroAddress(string addressType);

/**
 * @notice Delegation disallowed.
 *
 * @param token                             The token to delegate.
 */
error AV_NonWhitelistedDelegation(address token);

// ==================================== Ownable ERC721 ======================================
/// @notice All errors prefixed with OERC721_, to separate from other contracts in the protocol.

/**
 * @notice Function caller is not the owner.
 *
 * @param caller                             Msg.sender of the function call.
 */
error OERC721_CallerNotOwner(address caller);

// ==================================== Vault Factory ======================================
/// @notice All errors prefixed with VF_, to separate from other contracts in the protocol.

/**
 * @notice Zero address passed in where not allowed.
 *
 * @param addressType                  The name of the parameter for which a zero address was provided.
 */
error VF_ZeroAddress(string addressType);

/**
 * @notice Global index out of bounds.
 *
 * @param tokenId                            AW-V2 tokenId of the asset vault.
 */
error VF_TokenIdOutOfBounds(uint256 tokenId);

/**
 * @notice Cannot transfer with withdraw enabled.
 *
 * @param tokenId                            AW-V2 tokenId of the asset vault.
 */
error VF_NoTransferWithdrawEnabled(uint256 tokenId);

/**
 * @notice Not enough msg.value sent for the required mint fee.
 *
 * @param value                              The msg.value.
 * @param requiredMintFee                    The required mint fee.
 */
error VF_InsufficientMintFee(uint256 value, uint256 requiredMintFee);

/**
 * @notice Non-existant token id provided as argument.
 *
 * @param tokenId                       The ID of the token to lookup the URI for.
 */
error VF_DoesNotExist(uint256 tokenId);

// ================================== Call Whitelist ======================================
/// @notice All errors prefixed with CW_, to separate from other contracts in the protocol.

/**
 * @notice Cannot whitelist a call which has already been whitelisted.
 *
 * @param callee                             The contract to be added to CallWhitelist mapping.
 * @param selector                           The function selector to be added to CallWhitelist mapping.
 */
error CW_AlreadyWhitelisted(address callee, bytes4 selector);

/**
 * @notice Cannot remove a call from the CallWhitelist that has not yet been added.
 *
 * @param callee                             The contract to be removed from CallWhitelist mapping.
 * @param selector                           The function selector to be removed from CallWhitelist mapping.
 */
error CW_NotWhitelisted(address callee, bytes4 selector);

// ================================== Call Whitelist Delegation ======================================

/**
 * @notice Zero address passed in the constructor.
 */
error CWD_ZeroAddress();

/**
 * @notice The registry address provided is currently set as the registry.
 */
error CWD_RegistryAlreadySet();