// File: contracts/RepaymentController.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

import "./interfaces/IRepaymentController.sol";
import "./interfaces/IPromissoryNote.sol";
import "./interfaces/ILoanCore.sol";
import "./interfaces/IFeeController.sol";

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

import {
    RC_ZeroAddress,
    RC_CannotDereference,
    RC_InvalidState,
    RC_OnlyLender
} from "./errors/Lending.sol";

/**
 * @title RepaymentController
 * @author Non-Fungible Technologies, Inc.
 *
 * The Repayment Controller is the entry point for all loan lifecycle
 * operations in the Arcade.xyz lending protocol once a loan has begun.
 * This contract allows a caller to calculate an amount due on a loan,
 * repay an open loan, and claim collateral on a defaulted loan. It
 * is this contract's responsibility to verify loan conditions before
 * calling LoanCore.
 */
contract RepaymentController is IRepaymentController, InterestCalculator, FeeLookups {
    using SafeERC20 for IERC20;

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

    ILoanCore private immutable loanCore;
    IPromissoryNote private immutable lenderNote;
    IFeeController private immutable feeController;

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

    /**
     * @notice Creates a new repayment controller contract.
     *
     * @dev For this controller to work, it needs to be granted the REPAYER_ROLE
     *      in loan core after deployment.
     *
     * @param _loanCore                     The address of the loan core logic of the protocol.
     * @param _feeController                The address of the fee logic of the protocol.
     */
    constructor(address _loanCore, address _feeController) {
        if (_loanCore == address(0)) revert RC_ZeroAddress("loanCore");
        if (_feeController == address(0)) revert RC_ZeroAddress("feeController");

        loanCore = ILoanCore(_loanCore);
        lenderNote = loanCore.lenderNote();
        feeController = IFeeController(_feeController);
    }

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

    /**
     * @notice Repay an active loan, referenced by borrower note ID (equivalent to loan ID). The interest for a loan
     *         is calculated, and the principal plus interest is withdrawn from the caller.
     *         Anyone can repay a loan. Control is passed to LoanCore to complete repayment.
     *
     * @param  loanId               The ID of the loan.
     */
    function repay(uint256 loanId) external override {
        (uint256 amountFromBorrower, uint256 amountToLender) = _prepareRepay(loanId);

        // call repay function in loan core -  msg.sender will pay the amountFromBorrower
        loanCore.repay(loanId, msg.sender, amountFromBorrower, amountToLender);
    }

    /**
     * @notice Repay an active loan, referenced by borrower note ID (equivalent to loan ID). The interest for a loan
     *         is calculated, and the principal plus interest is withdrawn from the caller. Anyone can repay a loan.
     *         Using forceRepay will not send funds to the lender: instead, those funds will be made
     *         available for withdrawal in LoanCore. Can be used in cases where a borrower has funds to repay
     *         but the lender is not able to receive those tokens (e.g. token blacklist).
     *
     * @param  loanId               The ID of the loan.
     */
    function forceRepay(uint256 loanId) external override {
        (uint256 amountFromBorrower, uint256 amountToLender) = _prepareRepay(loanId);

        // call repay function in loan core -  msg.sender will pay the amountFromBorrower
        loanCore.forceRepay(loanId, msg.sender, amountFromBorrower, amountToLender);
    }

    /**
     * @notice Claim collateral on an active loan, referenced by lender note ID (equivalent to loan ID).
     *         The loan must be past the due date. No funds are collected
     *         from the borrower.
     *
     * @param  loanId               The ID of the loan.
     */
    function claim(uint256 loanId) external override {
        LoanLibrary.LoanData memory data = loanCore.getLoan(loanId);
        if (data.state == LoanLibrary.LoanState.DUMMY_DO_NOT_USE) revert RC_CannotDereference(loanId);

        // make sure that caller owns lender note
        // Implicitly checks if loan is active - if inactive, note will not exist
        address lender = lenderNote.ownerOf(loanId);
        if (lender != msg.sender) revert RC_OnlyLender(lender, msg.sender);

        LoanLibrary.LoanTerms memory terms = data.terms;
        uint256 interest = getInterestAmount(terms.principal, terms.proratedInterestRate);
        uint256 totalOwed = terms.principal + interest;

        uint256 claimFee = (totalOwed * data.feeSnapshot.lenderDefaultFee) / BASIS_POINTS_DENOMINATOR;

        loanCore.claim(loanId, claimFee);
    }

    /**
     * @notice Redeem a lender note for a completed return in return for funds repaid in an earlier
     *         transaction via forceRepay. The lender note must be owned by the caller.
     *
     * @param loanId                    The ID of the lender note to redeem.
     */
    function redeemNote(uint256 loanId, address to) external override {
        if (to == address(0)) revert RC_ZeroAddress("to");

        LoanLibrary.LoanData memory data = loanCore.getLoan(loanId);
        (, uint256 amountOwed) = loanCore.getNoteReceipt(loanId);

        if (data.state != LoanLibrary.LoanState.Repaid) revert RC_InvalidState(data.state);
        address lender = lenderNote.ownerOf(loanId);
        if (lender != msg.sender) revert RC_OnlyLender(lender, msg.sender);

        uint256 redeemFee = (amountOwed * feeController.getLendingFee(FL_08)) / BASIS_POINTS_DENOMINATOR;

        loanCore.redeemNote(loanId, redeemFee, to);
    }

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

    /**
     * @dev Shared logic to perform validation and calculations for repay and forceRepay.
     *
     * @param loanId               The ID of the loan.
     *
     * @return amountFromBorrower   The amount to collect from the borrower.
     * @return amountToLender       The amount owed to the lender.
     */
    function _prepareRepay(uint256 loanId) internal view returns (uint256 amountFromBorrower, uint256 amountToLender) {
        LoanLibrary.LoanData memory data = loanCore.getLoan(loanId);
        if (data.state == LoanLibrary.LoanState.DUMMY_DO_NOT_USE) revert RC_CannotDereference(loanId);
        if (data.state != LoanLibrary.LoanState.Active) revert RC_InvalidState(data.state);

        LoanLibrary.LoanTerms memory terms = data.terms;

        uint256 interest = getInterestAmount(terms.principal, terms.proratedInterestRate);

        uint256 interestFee = (interest * data.feeSnapshot.lenderInterestFee) / BASIS_POINTS_DENOMINATOR;
        uint256 principalFee = (terms.principal * data.feeSnapshot.lenderPrincipalFee) / BASIS_POINTS_DENOMINATOR;

        amountFromBorrower = terms.principal + interest;
        amountToLender = amountFromBorrower - interestFee - principalFee;
    }
}

// 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: contracts/interfaces/IRepaymentController.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

interface IRepaymentController {
    // ============== Lifeycle Operations ==============

    function repay(uint256 loanId) external;

    function forceRepay(uint256 loanId) external;

    function claim(uint256 loanId) external;

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

// 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/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/IFeeController.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

interface IFeeController {
    // ================ Structs ================

    struct FeesOrigination {
        uint16 borrowerOriginationFee;
        uint16 lenderOriginationFee;
        uint16 lenderDefaultFee;
        uint16 lenderInterestFee;
        uint16 lenderPrincipalFee;
    }

    struct FeesRollover {
        uint16 borrowerRolloverFee;
        uint16 lenderRolloverFee;
    }

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

    event SetLendingFee(bytes32 indexed id, uint16 fee);

    event SetVaultMintFee(uint64 fee);

    // ================ Getter/Setter =================

    function setLendingFee(bytes32 id, uint16 fee) external;

    function setVaultMintFee(uint64 fee) external;

    function getLendingFee(bytes32 id) external view returns (uint16);

    function getVaultMintFee() external view returns (uint64);

    function getFeesOrigination() external view returns (FeesOrigination memory);

    function getFeesRollover() external view returns (FeesRollover memory);

    function getMaxLendingFee(bytes32 id) external view returns (uint16);

    function getMaxVaultMintFee() external view returns (uint64);
}
// 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/libraries/FeeLookups.sol



// SPDX-License-Identifier: MIT

pragma solidity 0.8.18;

/**
 * @title FeeLookups
 * @author Non-Fungible Technologies, Inc.
 *
 * Enumerates unique identifiers for fee identifiers
 * that the lending protocol uses.
 */
abstract contract FeeLookups {
    /// @dev Origination fees: amount in bps, payable in loan token
    bytes32 public constant FL_01 = keccak256("BORROWER_ORIGINATION_FEE");
    bytes32 public constant FL_02 = keccak256("LENDER_ORIGINATION_FEE");

    /// @dev Rollover fees: amount in bps, payable in loan token
    bytes32 public constant FL_03 = keccak256("BORROWER_ROLLOVER_FEE");
    bytes32 public constant FL_04 = keccak256("LENDER_ROLLOVER_FEE");

    /// @dev Loan closure fees: amount in bps, payable in loan token
    bytes32 public constant FL_05 = keccak256("LENDER_DEFAULT_FEE");
    bytes32 public constant FL_06 = keccak256("LENDER_INTEREST_FEE");
    bytes32 public constant FL_07 = keccak256("LENDER_PRINCIPAL_FEE");
    bytes32 public constant FL_08 = keccak256("LENDER_REDEEM_FEE");
}

// 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: 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/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/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/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);
}