// File: contracts/CyanPaymentPlanV1.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.13;

import '@openzeppelin/contracts/access/AccessControl.sol';
import '@openzeppelin/contracts/security/ReentrancyGuard.sol';
import '@openzeppelin/contracts/utils/cryptography/ECDSA.sol';

import './CyanWrappedNFTV1.sol';
import './CyanVaultV1.sol';

contract CyanPaymentPlanV1 is AccessControl, ReentrancyGuard {
    using ECDSA for bytes32;

    bytes32 public constant CYAN_ROLE = keccak256('CYAN_ROLE');
    uint256 private _claimableServiceFee;
    address private _cyanSigner;

    event CreatedBNPL(
        address indexed wNFTContract,
        uint256 indexed tokenId,
        uint256 amount,
        uint256 interestRate
    );
    event FundedBNPL(address indexed wNFTContract, uint256 indexed tokenId);
    event ActivatedBNPL(address indexed wNFTContract, uint256 indexed tokenId);
    event ActivatedAdminFundedBNPL(
        address indexed wNFTContract,
        uint256 indexed tokenId
    );
    event RejectedBNPL(address indexed wNFTContract, uint256 indexed tokenId);
    event CreatedPAWN(
        address indexed wNFTContract,
        uint256 indexed tokenId,
        uint256 amount,
        uint256 interestRate
    );
    event LiquidatedPaymentPlan(
        address indexed wNFTContract,
        uint256 indexed tokenId,
        uint256 estimatedPrice,
        uint256 unpaidAmount,
        address lastOwner
    );
    event Paid(
        address indexed wNFTContract,
        uint256 indexed tokenId,
        address indexed from,
        uint256 amount
    );
    event Completed(
        address indexed wNFTContract,
        uint256 indexed tokenId,
        address indexed from,
        uint256 amount,
        address receiver
    );

    enum PaymentPlanStatus {
        BNPL_CREATED,
        BNPL_FUNDED,
        BNPL_ACTIVE,
        BNPL_DEFAULTED,
        PAWN_ACTIVE,
        PAWN_DEFAULTED
    }
    struct PaymentPlan {
        uint256 amount;
        uint256 interestRate;
        uint256 createdDate;
        uint256 term;
        address createdUserAddress;
        uint8 totalNumberOfPayments;
        uint8 counterPaidPayments;
        PaymentPlanStatus status;
    }

    mapping(address => mapping(uint256 => PaymentPlan)) public _paymentPlan;

    constructor(address cyanSigner, address cyanSuperAdmin) {
        _claimableServiceFee = 0;
        _cyanSigner = cyanSigner;
        _setupRole(DEFAULT_ADMIN_ROLE, cyanSuperAdmin);
        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
    }

    /**
     * @notice Create BNPL payment plan
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     * @param amount Original price of the token
     * @param interestRate Cyan interest rate
     * @param signedBlockNum Signed block number
     * @param term Term of payment plan in seconds
     * @param totalNumberOfPayments Total number of payments required for completion
     * @param signature Signature signed by Cyan signer
     */
    function createBNPLPaymentPlan(
        address wNFTContract,
        uint256 wNFTTokenId,
        uint256 amount,
        uint256 interestRate,
        uint256 signedBlockNum,
        uint256 term,
        uint8 totalNumberOfPayments,
        bytes memory signature
    ) external payable nonReentrant {
        verifySignature(
            wNFTContract,
            wNFTTokenId,
            amount,
            interestRate,
            signedBlockNum,
            term,
            totalNumberOfPayments,
            signature
        );
        require(
            signedBlockNum <= block.number,
            'Signed block number must be older'
        );
        require(signedBlockNum + 50 >= block.number, 'Signature expired');
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments == 0,
            'Payment plan already exists'
        );
        require(amount > 0, 'Price of token is non-positive');
        require(interestRate > 0, 'Interest rate is non-positive');
        require(msg.value > 0, 'Downpayment amount is non-positive');
        require(term > 0, 'Term is non-positive');
        require(
            totalNumberOfPayments > 0,
            'Total number of payments is non-positive'
        );

        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == false,
            'Token is already wrapped'
        );

        _paymentPlan[wNFTContract][wNFTTokenId] = PaymentPlan(
            amount, //amount
            interestRate, //interestRate
            block.timestamp, // createdDate
            term, //term
            msg.sender, // createdUserAddress
            totalNumberOfPayments, // totalNumberOfPayments
            0, //counterPaidPayments
            PaymentPlanStatus.BNPL_CREATED // status
        );

        (, , , uint256 currentPayment, ) = getNextPayment(
            wNFTContract,
            wNFTTokenId
        );
        require(currentPayment == msg.value, 'Downpayment amount incorrect');

        _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments++;

        emit CreatedBNPL(wNFTContract, wNFTTokenId, amount, interestRate);
    }

    /**
     * @notice Lending ETH from Vault for BNPL payment plan
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     */
    function fundBNPL(address wNFTContract, uint256 wNFTTokenId)
        external
        nonReentrant
        onlyRole(CYAN_ROLE)
    {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments == 1,
            'Only downpayment must be paid'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.BNPL_CREATED,
            'BNPL payment plan must be at CREATED stage'
        );
        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == false,
            'Wrapped token exist'
        );

        _paymentPlan[wNFTContract][wNFTTokenId].status = PaymentPlanStatus
            .BNPL_FUNDED;

        address _cyanVaultAddress = _cyanWrappedNFTV1.getCyanVaultAddress();
        CyanVaultV1 _cyanVaultV1 = CyanVaultV1(payable(_cyanVaultAddress));
        _cyanVaultV1.lend(
            msg.sender,
            _paymentPlan[wNFTContract][wNFTTokenId].amount
        );

        emit FundedBNPL(wNFTContract, wNFTTokenId);
    }

    /**
     * @notice Activating a BNPL payment plan
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     */
    function activateBNPL(address wNFTContract, uint256 wNFTTokenId)
        external
        nonReentrant
        onlyRole(CYAN_ROLE)
    {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments == 1,
            'Only downpayment must be paid'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.BNPL_FUNDED,
            'BNPL payment plan must be at FUNDED stage'
        );
        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == false,
            'Wrapped token exist'
        );

        (
            uint256 payAmountForCollateral,
            uint256 payAmountForInterest,
            uint256 payAmountForService,
            ,

        ) = getNextPayment(wNFTContract, wNFTTokenId);

        _cyanWrappedNFTV1.wrap(
            msg.sender,
            _paymentPlan[wNFTContract][wNFTTokenId].createdUserAddress,
            wNFTTokenId
        );

        _paymentPlan[wNFTContract][wNFTTokenId].status = PaymentPlanStatus
            .BNPL_ACTIVE;

        _claimableServiceFee += payAmountForService;

        address _cyanVaultAddress = _cyanWrappedNFTV1.getCyanVaultAddress();
        transferEarnedAmountToCyanVault(
            _cyanVaultAddress,
            payAmountForCollateral,
            payAmountForInterest
        );

        emit ActivatedBNPL(wNFTContract, wNFTTokenId);
    }

    /**
     * @notice Activating a BNPL payment plan that admin funded
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     */
    function activateAdminFundedBNPL(address wNFTContract, uint256 wNFTTokenId)
        external
        nonReentrant
        onlyRole(CYAN_ROLE)
    {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments == 1,
            'Only downpayment must be paid'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.BNPL_CREATED,
            'BNPL payment plan must be at CREATED stage'
        );
        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == false,
            'Wrapped token exist'
        );

        (
            uint256 payAmountForCollateral,
            uint256 payAmountForInterest,
            uint256 payAmountForService,
            ,

        ) = getNextPayment(wNFTContract, wNFTTokenId);

        _cyanWrappedNFTV1.wrap(
            msg.sender,
            _paymentPlan[wNFTContract][wNFTTokenId].createdUserAddress,
            wNFTTokenId
        );

        _paymentPlan[wNFTContract][wNFTTokenId].status = PaymentPlanStatus
            .BNPL_ACTIVE;

        _claimableServiceFee += payAmountForService;

        address _cyanVaultAddress = _cyanWrappedNFTV1.getCyanVaultAddress();
        CyanVaultV1 _cyanVaultV1 = CyanVaultV1(payable(_cyanVaultAddress));
        // Admin already funded the plan, so Vault is transfering equal amount of ETH to admin.
        _cyanVaultV1.lend(
            msg.sender,
            _paymentPlan[wNFTContract][wNFTTokenId].amount
        );
        _cyanVaultV1.earn{value: payAmountForCollateral + payAmountForInterest}(
            payAmountForCollateral,
            payAmountForInterest
        );

        emit ActivatedAdminFundedBNPL(wNFTContract, wNFTTokenId);
    }

    /**
     * @notice Create PAWN payment plan
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     * @param amount Collateral amount
     * @param interestRate Cyan interest rate
     * @param signedBlockNum Signed block number
     * @param term Term of payment plan in seconds
     * @param totalNumberOfPayments Total number of payments required for completion
     * @param signature Signature signed by Cyan signer
     */
    function createPAWNPaymentPlan(
        address wNFTContract,
        uint256 wNFTTokenId,
        uint256 amount,
        uint256 interestRate,
        uint256 signedBlockNum,
        uint256 term,
        uint8 totalNumberOfPayments,
        bytes memory signature
    ) external nonReentrant {
        verifySignature(
            wNFTContract,
            wNFTTokenId,
            amount,
            interestRate,
            signedBlockNum,
            term,
            totalNumberOfPayments,
            signature
        );
        require(
            signedBlockNum <= block.number,
            'Signed block number must be older'
        );
        require(signedBlockNum + 50 >= block.number, 'Signature expired');
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments == 0,
            'Payment plan already exists'
        );
        require(amount > 0, 'Collateral amount is non-positive');
        require(interestRate > 0, 'Interest rate is non-positive');
        require(term > 0, 'Term is non-positive');
        require(
            totalNumberOfPayments > 0,
            'Total number of payments is non-positive'
        );

        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == false,
            'Token is already wrapped'
        );

        _paymentPlan[wNFTContract][wNFTTokenId] = PaymentPlan(
            amount, //amount
            interestRate, //interestRate
            block.timestamp + term, // createdDate
            term, //term
            msg.sender, // createdUserAddress
            totalNumberOfPayments, // totalNumberOfPayments
            0, // counterPaidPayments
            PaymentPlanStatus.PAWN_ACTIVE // status
        );

        _cyanWrappedNFTV1.wrap(msg.sender, msg.sender, wNFTTokenId);

        address _cyanVaultAddress = _cyanWrappedNFTV1.getCyanVaultAddress();
        CyanVaultV1 _cyanVaultV1 = CyanVaultV1(payable(_cyanVaultAddress));
        _cyanVaultV1.lend(msg.sender, amount);

        emit CreatedPAWN(wNFTContract, wNFTTokenId, amount, interestRate);
    }

    /**
     * @notice Liquidate defaulted payment plan
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     * @param estimatedTokenValue Estimated value of defaulted NFT
     */
    function liquidate(
        address wNFTContract,
        uint256 wNFTTokenId,
        uint256 estimatedTokenValue
    ) external nonReentrant onlyRole(CYAN_ROLE) {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments >
                _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments,
            'Total payment done'
        );
        (, , , , uint256 dueDate) = getNextPayment(wNFTContract, wNFTTokenId);

        require(dueDate < block.timestamp, 'Next payment is still due');

        uint256 unpaidAmount = 0;
        for (
            ;
            // Until the last payment
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments <
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments;
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments++
        ) {
            (uint256 payAmountForCollateral, , , , ) = getNextPayment(
                wNFTContract,
                wNFTTokenId
            );
            unpaidAmount += payAmountForCollateral;
        }
        require(unpaidAmount > 0, 'Unpaid is non-positive');

        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == true,
            "Wrapped token doesn't exist"
        );
        address lastOwner = _cyanWrappedNFTV1.ownerOf(wNFTTokenId);
        _cyanWrappedNFTV1.unwrap(
            wNFTTokenId,
            /* isDefaulted = */
            true
        );
        delete _paymentPlan[wNFTContract][wNFTTokenId];

        address _cyanVaultAddress = _cyanWrappedNFTV1.getCyanVaultAddress();
        require(_cyanVaultAddress != address(0), 'Cyan vault has zero address');
        CyanVaultV1 _cyanVaultV1 = CyanVaultV1(payable(_cyanVaultAddress));
        _cyanVaultV1.nftDefaulted(unpaidAmount, estimatedTokenValue);

        emit LiquidatedPaymentPlan(
            wNFTContract,
            wNFTTokenId,
            estimatedTokenValue,
            unpaidAmount,
            lastOwner
        );
    }

    /**
     * @notice Make a payment for the payment plan
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     */
    function pay(address wNFTContract, uint256 wNFTTokenId)
        external
        payable
        nonReentrant
    {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments >
                _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments,
            'Total payment done'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.BNPL_ACTIVE ||
                _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.PAWN_ACTIVE,
            'Payment plan must be at ACTIVE stage'
        );

        (
            uint256 payAmountForCollateral,
            uint256 payAmountForInterest,
            uint256 payAmountForService,
            uint256 currentPayment,
            uint256 dueDate
        ) = getNextPayment(wNFTContract, wNFTTokenId);

        require(currentPayment == msg.value, 'Wrong payment amount');
        require(dueDate >= block.timestamp, 'Payment due date is passed');
        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == true,
            "Wrapped token doesn't exist"
        );
        _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments++;
        _claimableServiceFee += payAmountForService;

        address _cyanVaultAddress = _cyanWrappedNFTV1.getCyanVaultAddress();
        transferEarnedAmountToCyanVault(
            _cyanVaultAddress,
            payAmountForCollateral,
            payAmountForInterest
        );
        if (
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments ==
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments
        ) {
            address receiver = _cyanWrappedNFTV1.ownerOf(wNFTTokenId);
            _cyanWrappedNFTV1.unwrap(
                wNFTTokenId,
                /* isDefaulted = */
                false
            );
            delete _paymentPlan[wNFTContract][wNFTTokenId];
            emit Completed(
                wNFTContract,
                wNFTTokenId,
                msg.sender,
                msg.value,
                receiver
            );
        } else {
            emit Paid(wNFTContract, wNFTTokenId, msg.sender, msg.value);
        }
    }

    /**
     * @notice Reject the payment plan
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     */
    function rejectBNPLPaymentPlan(address wNFTContract, uint256 wNFTTokenId)
        external
        nonReentrant
        onlyRole(CYAN_ROLE)
    {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments == 1,
            'Payment done other than downpayment for this plan'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.BNPL_CREATED,
            'BNPL payment plan must be at CREATED stage'
        );
        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == false,
            'Wrapped token exists'
        );

        (, , , uint256 currentPayment, ) = getNextPayment(
            wNFTContract,
            wNFTTokenId
        );

        // Returning downpayment to created user address
        payable(_paymentPlan[wNFTContract][wNFTTokenId].createdUserAddress)
            .transfer(currentPayment);
        delete _paymentPlan[wNFTContract][wNFTTokenId];

        emit RejectedBNPL(wNFTContract, wNFTTokenId);
    }

    /**
     * @notice Reject the payment plan after FUNDED
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     */
    function rejectBNPLPaymentPlanAfterFunded(
        address wNFTContract,
        uint256 wNFTTokenId
    ) external payable nonReentrant onlyRole(CYAN_ROLE) {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].counterPaidPayments == 1,
            'Payment done other than downpayment for this plan'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.BNPL_FUNDED,
            'BNPL payment plan must be at FUNDED stage'
        );
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].amount == msg.value,
            'Wrong fund return amount'
        );
        CyanWrappedNFTV1 _cyanWrappedNFTV1 = CyanWrappedNFTV1(wNFTContract);
        require(
            _cyanWrappedNFTV1.exists(wNFTTokenId) == false,
            'Wrapped token exists'
        );

        (, , , uint256 currentPayment, ) = getNextPayment(
            wNFTContract,
            wNFTTokenId
        );

        // Returning downpayment to created user address
        payable(_paymentPlan[wNFTContract][wNFTTokenId].createdUserAddress)
            .transfer(currentPayment);
        delete _paymentPlan[wNFTContract][wNFTTokenId];

        // Returning funded amount back to Vault
        address _cyanVaultAddress = _cyanWrappedNFTV1.getCyanVaultAddress();
        transferEarnedAmountToCyanVault(_cyanVaultAddress, msg.value, 0);

        emit RejectedBNPL(wNFTContract, wNFTTokenId);
    }

    /**
     * @notice Calculate payments for given amount and interest rate
     * @param amount amount of collateral
     * @param interestRate interest rate
     * @param numOfPayment Number of payments
     * @return First payment amount for collateral
     * @return Total payment amount for interest fee
     * @return First payment amount for interest fee
     * @return Total payment amount for service fee
     * @return First payment amount for service fee
     * @return First payment amount
     */
    function calculateIndividualPayments(
        uint256 amount,
        uint256 interestRate,
        uint8 numOfPayment
    )
        private
        pure
        returns (
            uint256,
            uint256,
            uint256,
            uint256,
            uint256,
            uint256
        )
    {
        // Payment amount for collateral
        uint256 payAmountForCollateral = amount / numOfPayment;

        // Calculating interest fee, Note that interest rate is x100
        uint256 interestFee = (amount * interestRate) / 10000;
        // Payment amount for interest fee payment
        uint256 payAmountForInterest = interestFee / numOfPayment;

        // Calculating 2.5% service fee
        uint256 serviceFee = amount / 40;
        // Payment amount for service fee payment
        uint256 payAmountForService = serviceFee / numOfPayment;

        // First amount
        uint256 currentPayment = payAmountForCollateral +
            payAmountForInterest +
            payAmountForService;

        return (
            payAmountForCollateral,
            interestFee,
            payAmountForInterest,
            serviceFee,
            payAmountForService,
            currentPayment
        );
    }

    /**
     * @notice Return next payment info
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     * @return Next payment amount for collateral
     * @return Next payment amount for interest fee
     * @return Next payment amount for service fee
     * @return Next payment amount
     * @return Due date
     */
    function getNextPayment(address wNFTContract, uint256 wNFTTokenId)
        public
        view
        returns (
            uint256,
            uint256,
            uint256,
            uint256,
            uint256
        )
    {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );
        PaymentPlan memory plan = _paymentPlan[wNFTContract][wNFTTokenId];
        (
            uint256 payAmountForCollateral,
            uint256 interestFee,
            uint256 payAmountForInterest,
            uint256 serviceFee,
            uint256 payAmountForService,
            uint256 currentPayment
        ) = calculateIndividualPayments(
                plan.amount,
                plan.interestRate,
                plan.totalNumberOfPayments
            );
        if (plan.counterPaidPayments + 1 == plan.totalNumberOfPayments) {
            // Last payment
            payAmountForCollateral =
                plan.amount -
                (payAmountForCollateral * plan.counterPaidPayments);
            payAmountForInterest =
                interestFee -
                (payAmountForInterest * plan.counterPaidPayments);
            payAmountForService =
                serviceFee -
                (payAmountForService * plan.counterPaidPayments);
            currentPayment =
                payAmountForCollateral +
                payAmountForInterest +
                payAmountForService;
        }

        return (
            payAmountForCollateral,
            payAmountForInterest,
            payAmountForService,
            currentPayment,
            plan.createdDate + plan.counterPaidPayments * plan.term
        );
    }

    /**
     * @notice Transfer earned amount to Cyan Vault
     * @param cyanVaultAddress Original price of the token
     * @param paidTokenPayment Paid token payment
     * @param paidInterestFee Paid interest fee
     */
    function transferEarnedAmountToCyanVault(
        address cyanVaultAddress,
        uint256 paidTokenPayment,
        uint256 paidInterestFee
    ) private {
        require(cyanVaultAddress != address(0), 'Cyan vault has zero address');
        CyanVaultV1 _cyanVaultV1 = CyanVaultV1(payable(cyanVaultAddress));
        _cyanVaultV1.earn{value: paidTokenPayment + paidInterestFee}(
            paidTokenPayment,
            paidInterestFee
        );
    }

    /**
     * @notice Return expected payment plan for given price and interest rate
     * @param amount Original price of the token
     * @param interestRate Interest rate
     * @param numOfPayment Number of payments
     * @return Original price of the token
     * @return Interest Fee
     * @return Service Fee
     * @return Downpayment amount
     * @return Total payment amount
     */
    function getExpectedPaymentPlan(
        uint256 amount,
        uint256 interestRate,
        uint8 numOfPayment
    )
        external
        pure
        returns (
            uint256,
            uint256,
            uint256,
            uint256,
            uint256
        )
    {
        (
            ,
            uint256 interestFee,
            ,
            uint256 serviceFee,
            ,
            uint256 currentPayment
        ) = calculateIndividualPayments(amount, interestRate, numOfPayment);

        uint256 totalPayment = amount + interestFee + serviceFee;
        return (amount, interestFee, serviceFee, currentPayment, totalPayment);
    }

    /**
     * @notice Check if payment plan is pending
     * @param wNFTContract Wrapped NFT contract address
     * @param wNFTTokenId Wrapped NFT token ID
     * @return PaymentPlanStatus
     */
    function getPaymentPlanStatus(address wNFTContract, uint256 wNFTTokenId)
        external
        view
        returns (PaymentPlanStatus)
    {
        require(
            _paymentPlan[wNFTContract][wNFTTokenId].totalNumberOfPayments != 0,
            'No payment plan found'
        );

        (, , , , uint256 dueDate) = getNextPayment(wNFTContract, wNFTTokenId);
        bool isDefaulted = block.timestamp > dueDate;

        if (isDefaulted == true) {
            if (
                _paymentPlan[wNFTContract][wNFTTokenId].status ==
                PaymentPlanStatus.PAWN_ACTIVE
            ) {
                return PaymentPlanStatus.PAWN_DEFAULTED;
            }
            return PaymentPlanStatus.BNPL_DEFAULTED;
        }
        return _paymentPlan[wNFTContract][wNFTTokenId].status;
    }

    /**
     * @notice Getting claimable service fee amount
     */
    function getClaimableServiceFee()
        external
        view
        onlyRole(CYAN_ROLE)
        returns (uint256)
    {
        return _claimableServiceFee;
    }

    /**
     * @notice Claiming collected service fee amount
     */
    function claimServiceFee()
        external
        nonReentrant
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        payable(msg.sender).transfer(_claimableServiceFee);
        _claimableServiceFee = 0;
    }

    function verifySignature(
        address wNFTContract,
        uint256 wNFTTokenId,
        uint256 amount,
        uint256 interestRate,
        uint256 timestamp,
        uint256 term,
        uint8 totalNumberOfPayments,
        bytes memory signature
    ) internal view {
        bytes32 msgHash = keccak256(
            abi.encodePacked(
                wNFTContract,
                wNFTTokenId,
                amount,
                interestRate,
                timestamp,
                term,
                totalNumberOfPayments
            )
        );
        bytes32 signedHash = keccak256(
            abi.encodePacked('\x19Ethereum Signed Message:\n32', msgHash)
        );
        require(
            signedHash.recover(signature) == _cyanSigner,
            'Invalid signature'
        );
    }

    function updateCyanSignerAddress(address cyanSigner)
        external
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        require(cyanSigner != address(0), 'Zero Cyan Signer address');
        _cyanSigner = cyanSigner;
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/AccessControl.sol)

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 revoked `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}.
     * ====
     *
     * NOTE: This function is deprecated in favor of {_grantRole}.
     */
    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);
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * Internal function without access restriction.
     */
    function _grantRole(bytes32 role, address account) internal virtual {
        if (!hasRole(role, account)) {
            _roles[role].members[account] = true;
            emit RoleGranted(role, account, _msgSender());
        }
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * Internal function without access restriction.
     */
    function _revokeRole(bytes32 role, address account) internal virtual {
        if (hasRole(role, account)) {
            _roles[role].members[account] = false;
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

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 making 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/cryptography/ECDSA.sol



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

pragma solidity ^0.8.0;

import "../Strings.sol";

/**
 * @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 Message, created from `s`. 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(bytes memory s) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
    }

    /**
     * @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/CyanWrappedNFTV1.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.13;

import '@openzeppelin/contracts/access/AccessControl.sol';
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC721/ERC721.sol';
import '@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol';
import '@openzeppelin/contracts/security/ReentrancyGuard.sol';

contract CyanWrappedNFTV1 is
    AccessControl,
    ERC721,
    ReentrancyGuard,
    ERC721Holder
{
    using Strings for uint256;

    bytes32 public constant CYAN_ROLE = keccak256('CYAN_ROLE');
    bytes32 public constant CYAN_PAYMENT_PLAN_ROLE =
        keccak256('CYAN_PAYMENT_PLAN_ROLE');

    string private baseURI;
    string private baseExtension;

    address private immutable _originalNFT;
    address private _cyanVaultAddress;
    ERC721 private immutable _originalNFTContract;

    event Wrap(
        address indexed from,
        address indexed to,
        uint256 indexed tokenId
    );
    event Unwrap(
        address indexed to,
        uint256 indexed tokenId,
        bool indexed isDefaulted
    );

    constructor(
        address originalNFT,
        address cyanVaultAddress,
        address cyanPaymentPlanContractAddress,
        address cyanSuperAdmin,
        string memory name,
        string memory symbol,
        string memory uri,
        string memory extension
    ) ERC721(name, symbol) {
        _originalNFT = originalNFT;
        _cyanVaultAddress = cyanVaultAddress;
        _originalNFTContract = ERC721(_originalNFT);

        baseURI = uri;
        baseExtension = extension;

        _setupRole(DEFAULT_ADMIN_ROLE, cyanSuperAdmin);
        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
        _setupRole(CYAN_PAYMENT_PLAN_ROLE, cyanPaymentPlanContractAddress);
    }

    function wrap(
        address from,
        address to,
        uint256 tokenId
    ) external nonReentrant onlyRole(CYAN_PAYMENT_PLAN_ROLE) {
        require(to != address(0), 'Wrap to the zero address');
        require(!_exists(tokenId), 'Token already wrapped');

        _safeMint(to, tokenId);
        _originalNFTContract.safeTransferFrom(from, address(this), tokenId);

        emit Wrap(from, to, tokenId);
    }

    function unwrap(uint256 tokenId, bool isDefaulted)
        external
        nonReentrant
        onlyRole(CYAN_PAYMENT_PLAN_ROLE)
    {
        require(_exists(tokenId), 'Token is not wrapped');

        address to;
        if (isDefaulted) {
            to = _cyanVaultAddress;
        } else {
            to = ownerOf(tokenId);
        }

        _burn(tokenId);
        _originalNFTContract.safeTransferFrom(address(this), to, tokenId);

        emit Unwrap(to, tokenId, isDefaulted);
    }

    function exists(uint256 tokenId) external view returns (bool) {
        return _exists(tokenId);
    }

    function getOriginalNFTAddress() external view returns (address) {
        return _originalNFT;
    }

    function getCyanVaultAddress() external view returns (address) {
        return _cyanVaultAddress;
    }

    function updateCyanVaultAddress(address cyanVaultAddress)
        external
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        require(cyanVaultAddress != address(0), 'Zero Cyan Vault address');
        _cyanVaultAddress = cyanVaultAddress;
    }

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

    function _baseExtension() internal view returns (string memory) {
        return baseExtension;
    }

    function setBaseURI(string calldata newBaseURI)
        external
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        baseURI = newBaseURI;
    }

    function setBaseExtension(string calldata newBaseExtension)
        public
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        baseExtension = newBaseExtension;
    }

    function tokenURI(uint256 tokenId)
        public
        view
        override
        returns (string memory)
    {
        string memory uri = _baseURI();
        if (bytes(uri).length > 0) {
            string memory extension = _baseExtension();
            if (bytes(extension).length > 0) {
                return
                    string(
                        abi.encodePacked(uri, tokenId.toString(), extension)
                    );
            }
            return string(abi.encodePacked(uri, tokenId.toString()));
        }

        return '';
    }

    function withdrawAirDroppedERC721(address contractAddress, uint256 tokenId)
        external
        nonReentrant
        onlyRole(CYAN_ROLE)
    {
        require(
            contractAddress != address(this),
            'Cannot withdraw own wrapped token'
        );
        require(
            contractAddress != _originalNFT,
            'Cannot withdraw original NFT of the wrapper contract'
        );
        ERC721 erc721Contract = ERC721(contractAddress);
        erc721Contract.safeTransferFrom(address(this), msg.sender, tokenId);
    }

    function withdrawAirDroppedERC20(address contractAddress, uint256 amount)
        external
        nonReentrant
        onlyRole(CYAN_ROLE)
    {
        IERC20 erc20Contract = IERC20(contractAddress);
        require(
            erc20Contract.balanceOf(address(this)) >= amount,
            'ERC20 balance not enough'
        );
        erc20Contract.transfer(msg.sender, amount);
    }

    function withdrawApprovedERC20(
        address contractAddress,
        address from,
        uint256 amount
    ) external nonReentrant onlyRole(CYAN_ROLE) {
        IERC20 erc20Contract = IERC20(contractAddress);
        require(
            erc20Contract.allowance(from, address(this)) >= amount,
            'ERC20 allowance not enough'
        );
        erc20Contract.transferFrom(from, msg.sender, amount);
    }

    function supportsInterface(bytes4 interfaceId)
        public
        view
        virtual
        override(ERC721, AccessControl)
        returns (bool)
    {
        return super.supportsInterface(interfaceId);
    }
}

// File: contracts/CyanVaultV1.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.13;

import "@openzeppelin/contracts/access/AccessControl.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import "@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol";
import "@openzeppelin/contracts/security/Pausable.sol";

import "./CyanVaultTokenV1.sol";
import "./IStableSwapSTETH.sol";

contract CyanVaultV1 is AccessControl, ReentrancyGuard, ERC721Holder, Pausable {
    bytes32 public constant CYAN_ROLE = keccak256("CYAN_ROLE");
    bytes32 public constant CYAN_PAYMENT_PLAN_ROLE =
        keccak256("CYAN_PAYMENT_PLAN_ROLE");
    bytes32 public constant CYAN_BALANCER_ROLE =
        keccak256("CYAN_BALANCER_ROLE");

    event DepositETH(
        address indexed from,
        uint256 ethAmount,
        uint256 tokenAmount
    );
    event Lend(address indexed to, uint256 amount);
    event Earn(uint256 paymentAmount, uint256 profitAmount);
    event NftDefaulted(uint256 unpaidAmount, uint256 estimatedPriceOfNFT);
    event NftLiquidated(uint256 defaultedAssetsAmount, uint256 soldAmount);
    event WithdrawETH(
        address indexed from,
        uint256 ethAmount,
        uint256 tokenAmount
    );
    event GetDefaultedNFT(
        address indexed to,
        address indexed contractAddress,
        uint256 indexed tokenId
    );
    event UpdatedDefaultedNFTAssetAmount(uint256 amount);
    event UpdatedServiceFeePercent(uint256 from, uint256 to);
    event UpdatedSafetyFundPercent(uint256 from, uint256 to);
    event ExchangedEthToStEth(uint256 ethAmount, uint256 receivedStEthAmount);
    event ExchangedStEthToEth(uint256 stEthAmount, uint256 receivedEthAmount);
    event ReceivedETH(uint256 amount, address indexed from);

    address public immutable _cyanVaultTokenAddress;
    CyanVaultTokenV1 private immutable _cyanVaultTokenContract;

    IERC20 private immutable _stEthTokenContract;
    IStableSwapSTETH private immutable _stableSwapSTETHContract;

    // Safety fund percent. (x100)
    uint256 public _safetyFundPercent;

    // Cyan service fee percent. (x100)
    uint256 public _serviceFeePercent;

    // Remaining amount of ETH
    uint256 private REMAINING_AMOUNT;

    // Total loaned amount
    uint256 private LOANED_AMOUNT;

    // Total defaulted NFT amount
    uint256 private DEFAULTED_NFT_ASSET_AMOUNT;

    // Cyan collected service fee
    uint256 private COLLECTED_SERVICE_FEE_AMOUNT;

    constructor(
        address cyanVaultTokenAddress,
        address cyanPaymentPlanAddress,
        address stEthTokenAddress,
        address curveStableSwapStEthAddress,
        address cyanSuperAdmin,
        uint256 safetyFundPercent,
        uint256 serviceFeePercent
    ) payable {
        _cyanVaultTokenAddress = cyanVaultTokenAddress;
        _cyanVaultTokenContract = CyanVaultTokenV1(_cyanVaultTokenAddress);
        _safetyFundPercent = safetyFundPercent;
        _serviceFeePercent = serviceFeePercent;

        LOANED_AMOUNT = 0;
        DEFAULTED_NFT_ASSET_AMOUNT = 0;
        REMAINING_AMOUNT = msg.value;

        _stEthTokenContract = IERC20(stEthTokenAddress);
        _stableSwapSTETHContract = IStableSwapSTETH(
            curveStableSwapStEthAddress
        );

        _setupRole(DEFAULT_ADMIN_ROLE, cyanSuperAdmin);
        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
        _setupRole(CYAN_PAYMENT_PLAN_ROLE, cyanPaymentPlanAddress);
    }

    // User stakes ETH
    function depositETH() external payable nonReentrant whenNotPaused {
        require(msg.value > 0, "Must deposit more than 0 ETH");

        // Cyan collecting service fee from deposits
        uint256 cyanServiceFee = (msg.value * _serviceFeePercent) / 10000;

        uint256 depositedAmount = msg.value - cyanServiceFee;
        uint256 mintAmount = calculateTokenByETH(depositedAmount);

        REMAINING_AMOUNT += depositedAmount;
        COLLECTED_SERVICE_FEE_AMOUNT += cyanServiceFee;
        _cyanVaultTokenContract.mint(msg.sender, mintAmount);

        emit DepositETH(msg.sender, depositedAmount, mintAmount);
    }

    // Cyan lends money from Vault to do BNPL or PAWN
    function lend(address to, uint256 amount)
        external
        nonReentrant
        whenNotPaused
        onlyRole(CYAN_PAYMENT_PLAN_ROLE)
    {
        uint256 maxWithdrableAmount = getMaxWithdrawableAmount();
        require(amount <= maxWithdrableAmount, "Not enough ETH in the Vault");

        LOANED_AMOUNT += amount;
        REMAINING_AMOUNT -= amount;
        payable(to).transfer(amount);

        emit Lend(to, amount);
    }

    // Cyan Payment Plan contract transfers paid amount back to Vault
    function earn(uint256 amount, uint256 profit)
        external
        payable
        nonReentrant
        onlyRole(CYAN_PAYMENT_PLAN_ROLE)
    {
        require(msg.value == amount + profit, "Wrong tranfer amount");

        REMAINING_AMOUNT += msg.value;
        if (LOANED_AMOUNT >= amount) {
            LOANED_AMOUNT -= amount;
        } else {
            LOANED_AMOUNT = 0;
        }

        emit Earn(amount, profit);
    }

    // When BNPL or PAWN plan defaults
    function nftDefaulted(uint256 unpaidAmount, uint256 estimatedPriceOfNFT)
        external
        nonReentrant
        onlyRole(CYAN_PAYMENT_PLAN_ROLE)
    {
        DEFAULTED_NFT_ASSET_AMOUNT += estimatedPriceOfNFT;

        if (LOANED_AMOUNT >= unpaidAmount) {
            LOANED_AMOUNT -= unpaidAmount;
        } else {
            LOANED_AMOUNT = 0;
        }

        emit NftDefaulted(unpaidAmount, estimatedPriceOfNFT);
    }

    // Liquidating defaulted BNPL or PAWN token and tranferred sold amount to Vault
    function liquidateNFT(uint256 totalDefaultedNFTAmount)
        external
        payable
        whenNotPaused
        onlyRole(CYAN_ROLE)
    {
        REMAINING_AMOUNT += msg.value;
        DEFAULTED_NFT_ASSET_AMOUNT = totalDefaultedNFTAmount;

        emit NftLiquidated(msg.value, totalDefaultedNFTAmount);
    }

    // User unstakes tokenAmount of tokens and gets back ETH
    function withdraw(uint256 amount) external nonReentrant whenNotPaused {
        require(amount > 0, "Non-positive token amount");

        uint256 balance = _cyanVaultTokenContract.balanceOf(msg.sender);
        require(balance >= amount, "Check the token balance");

        uint256 withdrawableTokenBalance = getWithdrawableBalance(msg.sender);
        require(
            amount <= withdrawableTokenBalance,
            "Not enough active balance in Cyan Vault"
        );

        uint256 withdrawETHAmount = calculateETHByToken(amount);

        REMAINING_AMOUNT -= withdrawETHAmount;
        _cyanVaultTokenContract.burn(msg.sender, amount);
        payable(msg.sender).transfer(withdrawETHAmount);

        emit WithdrawETH(msg.sender, withdrawETHAmount, amount);
    }

    // Cyan updating total amount of defaulted NFT assets
    function updateDefaultedNFTAssetAmount(uint256 amount)
        external
        whenNotPaused
        onlyRole(CYAN_ROLE)
    {
        DEFAULTED_NFT_ASSET_AMOUNT = amount;
        emit UpdatedDefaultedNFTAssetAmount(amount);
    }

    // Get defaulted NFT from Vault to Cyan Admin account
    function getDefaultedNFT(address contractAddress, uint256 tokenId)
        external
        nonReentrant
        whenNotPaused
        onlyRole(CYAN_ROLE)
    {
        require(contractAddress != address(0), "Zero contract address");

        IERC721 originalContract = IERC721(contractAddress);

        require(
            originalContract.ownerOf(tokenId) == address(this),
            "Vault isn't owner of the token"
        );

        originalContract.safeTransferFrom(address(this), msg.sender, tokenId);

        emit GetDefaultedNFT(msg.sender, contractAddress, tokenId);
    }

    function getWithdrawableBalance(address user)
        public
        view
        returns (uint256)
    {
        uint256 tokenBalance = _cyanVaultTokenContract.balanceOf(user);
        uint256 ethAmountForToken = calculateETHByToken(tokenBalance);
        uint256 maxWithdrawableAmount = getMaxWithdrawableAmount();

        if (ethAmountForToken <= maxWithdrawableAmount) {
            return tokenBalance;
        }
        return calculateTokenByETH(maxWithdrawableAmount);
    }

    function getMaxWithdrawableAmount() public view returns (uint256) {
        uint256 util = ((LOANED_AMOUNT + DEFAULTED_NFT_ASSET_AMOUNT) *
            _safetyFundPercent) / 10000;
        if (REMAINING_AMOUNT > util) {
            return REMAINING_AMOUNT - util;
        }
        return 0;
    }

    function getCurrentAssetAmounts()
        external
        view
        returns (
            uint256,
            uint256,
            uint256,
            uint256,
            uint256
        )
    {
        return (
            REMAINING_AMOUNT,
            LOANED_AMOUNT,
            DEFAULTED_NFT_ASSET_AMOUNT,
            COLLECTED_SERVICE_FEE_AMOUNT,
            _stEthTokenContract.balanceOf(address(this))
        );
    }

    function calculateTokenByETH(uint256 amount) public view returns (uint256) {
        (uint256 totalETH, uint256 totalToken) = getTotalEthAndToken();
        return (amount * totalToken) / totalETH;
    }

    function calculateETHByToken(uint256 amount) public view returns (uint256) {
        (uint256 totalETH, uint256 totalToken) = getTotalEthAndToken();
        return (amount * totalETH) / totalToken;
    }

    function getTotalEthAndToken() private view returns (uint256, uint256) {
        uint256 vaultStEthBalance = _stEthTokenContract.balanceOf(
            address(this)
        );
        uint256 stEthInEth = _stableSwapSTETHContract.get_dy(
            1,
            0,
            vaultStEthBalance
        );
        uint256 totalETH = REMAINING_AMOUNT +
            LOANED_AMOUNT +
            DEFAULTED_NFT_ASSET_AMOUNT +
            stEthInEth;
        uint256 totalToken = _cyanVaultTokenContract.totalSupply();

        return (totalETH, totalToken);
    }

    function exchangeEthToStEth(uint256 ethAmount, uint256 minStEthAmount)
        external
        nonReentrant
        onlyRole(CYAN_BALANCER_ROLE)
    {
        require(ethAmount > 0, "Exchanging ETH amount is zero");
        require(
            ethAmount <= REMAINING_AMOUNT,
            "Cannot exchange more than REMAINING_AMOUNT"
        );
        // Exchanging ETH to stETH
        uint256 receivedStEthAmount = _stableSwapSTETHContract.exchange{
            value: ethAmount
        }(0, 1, ethAmount, minStEthAmount);
        REMAINING_AMOUNT -= ethAmount;
        emit ExchangedEthToStEth(ethAmount, receivedStEthAmount);
    }

    function exchangeStEthToEth(uint256 stEthAmount, uint256 minEthAmount)
        external
        nonReentrant
        onlyRole(CYAN_BALANCER_ROLE)
    {
        require(stEthAmount > 0, "Exchanging stETH amount is zero");
        // Exchanging stETH to ETH
        _stEthTokenContract.approve(
            address(_stableSwapSTETHContract),
            stEthAmount
        );
        uint256 receivedEthAmount = _stableSwapSTETHContract.exchange(
            1,
            0,
            stEthAmount,
            minEthAmount
        );
        emit ExchangedStEthToEth(stEthAmount, receivedEthAmount);
    }

    function updateSafetyFundPercent(uint256 safetyFundPercent)
        external
        nonReentrant
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        require(
            safetyFundPercent <= 10000,
            "Safety fund percent must be equal or less than 100 percent"
        );
        emit UpdatedSafetyFundPercent(_safetyFundPercent, safetyFundPercent);
        _safetyFundPercent = safetyFundPercent;
    }

    function updateServiceFeePercent(uint256 serviceFeePercent)
        external
        nonReentrant
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        require(
            serviceFeePercent <= 200,
            "Service fee percent must not be greater than 2 percent"
        );
        emit UpdatedServiceFeePercent(_serviceFeePercent, serviceFeePercent);
        _serviceFeePercent = serviceFeePercent;
    }

    function collectServiceFee(uint256 amount)
        external
        nonReentrant
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        require(
            amount <= COLLECTED_SERVICE_FEE_AMOUNT,
            "Not enough collected service fee"
        );
        COLLECTED_SERVICE_FEE_AMOUNT -= amount;
        payable(msg.sender).transfer(amount);
    }

    function withdrawAirDroppedERC20(address contractAddress, uint256 amount)
        external
        nonReentrant
        onlyRole(CYAN_ROLE)
    {
        require(
            contractAddress != address(_stEthTokenContract),
            "Cannot withdraw stETH"
        );
        IERC20 erc20Contract = IERC20(contractAddress);
        require(
            erc20Contract.balanceOf(address(this)) >= amount,
            "ERC20 balance not enough"
        );
        erc20Contract.transfer(msg.sender, amount);
    }

    function withdrawApprovedERC20(
        address contractAddress,
        address from,
        uint256 amount
    ) external nonReentrant onlyRole(CYAN_ROLE) {
        require(
            contractAddress != address(_stEthTokenContract),
            "Cannot withdraw stETH"
        );
        IERC20 erc20Contract = IERC20(contractAddress);
        require(
            erc20Contract.allowance(from, address(this)) >= amount,
            "ERC20 allowance not enough"
        );
        erc20Contract.transferFrom(from, msg.sender, amount);
    }

    receive() external payable {
        REMAINING_AMOUNT += msg.value;
        emit ReceivedETH(msg.value, msg.sender);
    }

    fallback() external payable {
        REMAINING_AMOUNT += msg.value;
        emit ReceivedETH(msg.value, msg.sender);
    }

    function pause() external nonReentrant onlyRole(DEFAULT_ADMIN_ROLE) {
        _pause();
    }

    function unpause() external nonReentrant onlyRole(DEFAULT_ADMIN_ROLE) {
        _unpause();
    }
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)

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
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

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

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

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



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

pragma solidity ^0.8.0;

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

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

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

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

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

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



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

pragma solidity ^0.8.0;

import "./IERC165.sol";

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

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



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

pragma solidity ^0.8.0;

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

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)

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/token/ERC721/ERC721.sol



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

pragma solidity ^0.8.0;

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

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

    // Token name
    string private _name;

    // Token symbol
    string private _symbol;

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        _approve(to, tokenId);
    }

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

        return _tokenApprovals[tokenId];
    }

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

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

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

        _transfer(from, to, tokenId);
    }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

// File: @openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/utils/ERC721Holder.sol)

pragma solidity ^0.8.0;

import "../IERC721Receiver.sol";

/**
 * @dev Implementation of the {IERC721Receiver} interface.
 *
 * Accepts all token transfers.
 * Make sure the contract is able to use its token with {IERC721-safeTransferFrom}, {IERC721-approve} or {IERC721-setApprovalForAll}.
 */
contract ERC721Holder is IERC721Receiver {
    /**
     * @dev See {IERC721Receiver-onERC721Received}.
     *
     * Always returns `IERC721Receiver.onERC721Received.selector`.
     */
    function onERC721Received(
        address,
        address,
        uint256,
        bytes memory
    ) public virtual override returns (bytes4) {
        return this.onERC721Received.selector;
    }
}

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



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

pragma solidity ^0.8.0;

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

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

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

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

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

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

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
     * are aware of the ERC721 protocol to prevent tokens from being forever locked.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 tokenId
    ) external;

    /**
     * @dev Gives permission to `to` to transfer `tokenId` token to another account.
     * The approval is cleared when the token is transferred.
     *
     * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
     *
     * Requirements:
     *
     * - The caller must own the token or be an approved operator.
     * - `tokenId` must exist.
     *
     * Emits an {Approval} event.
     */
    function approve(address to, uint256 tokenId) external;

    /**
     * @dev Returns the account approved for `tokenId` token.
     *
     * Requirements:
     *
     * - `tokenId` must exist.
     */
    function getApproved(uint256 tokenId) external view returns (address operator);

    /**
     * @dev Approve or remove `operator` as an operator for the caller.
     * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
     *
     * Requirements:
     *
     * - The `operator` cannot be the caller.
     *
     * Emits an {ApprovalForAll} event.
     */
    function setApprovalForAll(address operator, bool _approved) external;

    /**
     * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
     *
     * See {setApprovalForAll}
     */
    function isApprovedForAll(address owner, address operator) external view returns (bool);

    /**
     * @dev Safely transfers `tokenId` token from `from` to `to`.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must exist and be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
     *
     * Emits a {Transfer} event.
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 tokenId,
        bytes calldata data
    ) external;
}

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



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

pragma solidity ^0.8.0;

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

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



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

pragma solidity ^0.8.0;

import "../IERC721.sol";

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

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

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

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



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

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/security/Pausable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/Pausable.sol)

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: contracts/CyanVaultTokenV1.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.13;

import '@openzeppelin/contracts/access/AccessControl.sol';
import '@openzeppelin/contracts/token/ERC20/ERC20.sol';

contract CyanVaultTokenV1 is AccessControl, ERC20 {
    bytes32 public constant CYAN_VAULT_ROLE = keccak256('CYAN_VAULT_ROLE');

    constructor(
        string memory name,
        string memory symbol,
        uint256 initialSupply,
        address cyanSuperAdmin
    ) ERC20(name, symbol) {
        _mint(cyanSuperAdmin, initialSupply);
        _setupRole(DEFAULT_ADMIN_ROLE, cyanSuperAdmin);
        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
    }

    function mint(address to, uint256 amount)
        external
        onlyRole(CYAN_VAULT_ROLE)
    {
        require(to != address(0), 'Mint to the zero address');
        _mint(to, amount);
    }

    function burn(address from, uint256 amount)
        external
        onlyRole(CYAN_VAULT_ROLE)
    {
        require(balanceOf(from) >= amount, 'Balance not enough');
        _burn(from, amount);
    }

    function burnAdminToken(uint256 amount)
        external
        onlyRole(DEFAULT_ADMIN_ROLE)
    {
        require(balanceOf(msg.sender) >= amount, 'Balance not enough');
        _burn(msg.sender, amount);
    }
}

// File: contracts/IStableSwapSTETH.sol



// SPDX-License-Identifier: MIT
pragma solidity 0.8.13;

interface IStableSwapSTETH {
    /**
     * @notice Perform an exchange between two coins
     * @dev Index values can be found via the `coins` public getter method
     * @param i Index value for the coin to send
     * @param j Index valie of the coin to recieve
     * @param dx Amount of `i` being exchanged
     * @param min_dy Minimum amount of `j` to receive
     * @return Actual amount of `j` received
     */
    function exchange(
        int128 i,
        int128 j,
        uint256 dx,
        uint256 min_dy
    ) external payable returns (uint256);

    function get_dy(
        int128 i,
        int128 j,
        uint256 dx
    ) external view returns (uint256);
}

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



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);

        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }

        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        uint256 currentAllowance = _allowances[_msgSender()][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(_msgSender(), spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**
     * @dev Moves `amount` of tokens from `sender` to `recipient`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        uint256 senderBalance = _balances[sender];
        require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] += amount;

        emit Transfer(sender, recipient, amount);

        _afterTokenTransfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens 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 amount
    ) internal virtual {}

    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been 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 _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}

// File: @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;

import "../IERC20.sol";

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

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

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}