Contract Address Details

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

import "./Marketplace.sol";

/**
 * @title MarketplaceTestnet
 * @notice SAMO ZA TESTNET (943). Enak kot Marketplace, le da je casovni zamik
 *         skrajsan na 10 minut, da je postopek napoved → izvedba mogoce
 *         preizkusiti v eni seji namesto v dveh dneh.
 *
 * ZAKAJ LOCENA POGODBA IN NE STIKALO:
 *   Stikalo bi bilo mogoce pomotoma nastaviti na mainnetu in nihce ne bi opazil —
 *   zamik bi bil videti prisoten, a bi bil brez ucinka. Locena pogodba tega ne
 *   dopusca: skrajsani zamik fizicno ne obstaja v Marketplace.sol. Isti prijem
 *   kot pri KYCWhitelistTestnet.
 *
 * ⚠️ Te pogodbe se NE deploya na mainnet (369).
 */
contract MarketplaceTestnet is Marketplace {
    constructor(address _usdc, address _feeRecipient, address _kyc)
        Marketplace(_usdc, _feeRecipient, _kyc)
    {}

    function zamik() public pure override returns (uint256) {
        return 10 minutes;
    }
}
        

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC165.sol)

pragma solidity >=0.4.16;

import {IERC165} from "../utils/introspection/IERC165.sol";
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC20/IERC20.sol)

pragma solidity >=0.4.16;

/**
 * @dev Interface of the ERC-20 standard as defined in the ERC.
 */
interface IERC20 {
    /**
     * @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);

    /**
     * @dev Returns the value of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)

pragma solidity ^0.8.20;

/**
 * @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;
    }

    function _contextSuffixLength() internal view virtual returns (uint256) {
        return 0;
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC1363.sol)

pragma solidity >=0.6.2;

import {IERC20} from "./IERC20.sol";
import {IERC165} from "./IERC165.sol";

/**
 * @title IERC1363
 * @dev Interface of the ERC-1363 standard as defined in the https://eips.ethereum.org/EIPS/eip-1363[ERC-1363].
 *
 * Defines an extension interface for ERC-20 tokens that supports executing code on a recipient contract
 * after `transfer` or `transferFrom`, or code on a spender contract after `approve`, in a single transaction.
 */
interface IERC1363 is IERC20, IERC165 {
    /*
     * Note: the ERC-165 identifier for this interface is 0xb0202a11.
     * 0xb0202a11 ===
     *   bytes4(keccak256('transferAndCall(address,uint256)')) ^
     *   bytes4(keccak256('transferAndCall(address,uint256,bytes)')) ^
     *   bytes4(keccak256('transferFromAndCall(address,address,uint256)')) ^
     *   bytes4(keccak256('transferFromAndCall(address,address,uint256,bytes)')) ^
     *   bytes4(keccak256('approveAndCall(address,uint256)')) ^
     *   bytes4(keccak256('approveAndCall(address,uint256,bytes)'))
     */

    /**
     * @dev Moves a `value` amount of tokens from the caller's account to `to`
     * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
     * @param to The address which you want to transfer to.
     * @param value The amount of tokens to be transferred.
     * @return A boolean value indicating whether the operation succeeded unless throwing.
     */
    function transferAndCall(address to, uint256 value) external returns (bool);

    /**
     * @dev Moves a `value` amount of tokens from the caller's account to `to`
     * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
     * @param to The address which you want to transfer to.
     * @param value The amount of tokens to be transferred.
     * @param data Additional data with no specified format, sent in call to `to`.
     * @return A boolean value indicating whether the operation succeeded unless throwing.
     */
    function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool);

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
     * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
     * @param from The address which you want to send tokens from.
     * @param to The address which you want to transfer to.
     * @param value The amount of tokens to be transferred.
     * @return A boolean value indicating whether the operation succeeded unless throwing.
     */
    function transferFromAndCall(address from, address to, uint256 value) external returns (bool);

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
     * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
     * @param from The address which you want to send tokens from.
     * @param to The address which you want to transfer to.
     * @param value The amount of tokens to be transferred.
     * @param data Additional data with no specified format, sent in call to `to`.
     * @return A boolean value indicating whether the operation succeeded unless throwing.
     */
    function transferFromAndCall(address from, address to, uint256 value, bytes calldata data) external returns (bool);

    /**
     * @dev Sets a `value` amount of tokens as the allowance of `spender` over the
     * caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
     * @param spender The address which will spend the funds.
     * @param value The amount of tokens to be spent.
     * @return A boolean value indicating whether the operation succeeded unless throwing.
     */
    function approveAndCall(address spender, uint256 value) external returns (bool);

    /**
     * @dev Sets a `value` amount of tokens as the allowance of `spender` over the
     * caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
     * @param spender The address which will spend the funds.
     * @param value The amount of tokens to be spent.
     * @param data Additional data with no specified format, sent in call to `spender`.
     * @return A boolean value indicating whether the operation succeeded unless throwing.
     */
    function approveAndCall(address spender, uint256 value, bytes calldata data) external returns (bool);
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/StorageSlot.sol)
// This file was procedurally generated from scripts/generate/templates/StorageSlot.js.

pragma solidity ^0.8.20;

/**
 * @dev Library for reading and writing primitive types to specific storage slots.
 *
 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
 * This library helps with reading and writing to such slots without the need for inline assembly.
 *
 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
 *
 * Example usage to set ERC-1967 implementation slot:
 * ```solidity
 * contract ERC1967 {
 *     // Define the slot. Alternatively, use the SlotDerivation library to derive the slot.
 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
 *
 *     function _getImplementation() internal view returns (address) {
 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
 *     }
 *
 *     function _setImplementation(address newImplementation) internal {
 *         require(newImplementation.code.length > 0);
 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
 *     }
 * }
 * ```
 *
 * TIP: Consider using this library along with {SlotDerivation}.
 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }

    struct BooleanSlot {
        bool value;
    }

    struct Bytes32Slot {
        bytes32 value;
    }

    struct Uint256Slot {
        uint256 value;
    }

    struct Int256Slot {
        int256 value;
    }

    struct StringSlot {
        string value;
    }

    struct BytesSlot {
        bytes value;
    }

    /**
     * @dev Returns an `AddressSlot` with member `value` located at `slot`.
     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        assembly ("memory-safe") {
            r.slot := slot
        }
    }

    /**
     * @dev Returns a `BooleanSlot` with member `value` located at `slot`.
     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        assembly ("memory-safe") {
            r.slot := slot
        }
    }

    /**
     * @dev Returns a `Bytes32Slot` with member `value` located at `slot`.
     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        assembly ("memory-safe") {
            r.slot := slot
        }
    }

    /**
     * @dev Returns a `Uint256Slot` with member `value` located at `slot`.
     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        assembly ("memory-safe") {
            r.slot := slot
        }
    }

    /**
     * @dev Returns a `Int256Slot` with member `value` located at `slot`.
     */
    function getInt256Slot(bytes32 slot) internal pure returns (Int256Slot storage r) {
        assembly ("memory-safe") {
            r.slot := slot
        }
    }

    /**
     * @dev Returns a `StringSlot` with member `value` located at `slot`.
     */
    function getStringSlot(bytes32 slot) internal pure returns (StringSlot storage r) {
        assembly ("memory-safe") {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `StringSlot` representation of the string storage pointer `store`.
     */
    function getStringSlot(string storage store) internal pure returns (StringSlot storage r) {
        assembly ("memory-safe") {
            r.slot := store.slot
        }
    }

    /**
     * @dev Returns a `BytesSlot` with member `value` located at `slot`.
     */
    function getBytesSlot(bytes32 slot) internal pure returns (BytesSlot storage r) {
        assembly ("memory-safe") {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `BytesSlot` representation of the bytes storage pointer `store`.
     */
    function getBytesSlot(bytes storage store) internal pure returns (BytesSlot storage r) {
        assembly ("memory-safe") {
            r.slot := store.slot
        }
    }
}
          

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

import "@openzeppelin/contracts/access/Ownable.sol";

/**
 * @title AdminZamik
 * @notice Casovni zamik na nevarne admin spremembe.
 *
 * ZAKAJ TO OBSTAJA
 * ----------------
 * Owner kljuc na tej platformi NE more krasti: ne more kovati zetonov, ne more
 * premikati tujih zetonov in ne more v escrow. Kar PA lahko, je tiho zamenjati
 * nastavitve pod nogami uporabnikov — KYC listo, placilni token, prijavljeno
 * vrednost sredstva.
 *
 * Vsi trije so napadi, ki jih je mogoce VIDETI VNAPREJ. Zato jih ne branimo z
 * multisigom (ki varuje lastnika kljuca), ampak s casovnim zamikom (ki varuje
 * UPORABNIKA): sprememba se mora najprej javno napovedati, sele po zamiku jo je
 * mogoce izvesti. Uporabnik ima ves ta cas, da spremembo vidi in izstopi.
 *
 * Namenoma NI zunanje timelock pogodbe kot lastnika. Tak vzorec doda tveganje
 * nedosegljivosti: ce lastniku kdaj ne uspe sestaviti transakcije skozi tujo
 * pogodbo, so kontrakti zamrznjeni za vedno. Tu je zamik vgrajen, lastnik pa
 * ostane navadna denarnica.
 *
 * KAJ ZAMIK NE POKRIVA (namerno)
 * ------------------------------
 *   - pause()   — zasilna zavora mora biti takojsnja, sicer ni zavora
 *   - unpause() — vrnitev v obratovanje naj bo hitra
 *   - odvzem pravice zaustavljalca — ob razkritem kljucu ga moras vreci TAKOJ
 * Nevarnost caka, zasilna zavora ne.
 */
abstract contract AdminZamik is Ownable {
    /// @notice Rok, v katerem je napoved uporabna. Po njem potece.
    /// @dev Brez tega bi stara napoved lezala na verigi kot nabita puska:
    ///      napoves nekaj neopaznega danes, izvedes cez pol leta, ko nihce vec
    ///      ne gleda. Napoved, ki ni bila izvedena v roku, je treba ponoviti.
    uint256 public constant ROK = 7 days;

    /// @notice id napovedi → cas, od katerega je izvedljiva (0 = ni napovedi)
    mapping(bytes32 => uint256) public izvedljivoOd;

    event SpremembaNapovedana(bytes32 indexed id, string kaj, uint256 izvedljivoOd, uint256 potece);
    event SpremembaIzvedena(bytes32 indexed id, string kaj);
    event SpremembaPreklicana(bytes32 indexed id, string kaj);

    /// @notice Koliko casa mora sprememba cakati. Na mainnetu 48 ur.
    /// @dev virtual samo zato, da lahko testnetna razlicica skrajsa cakanje na
    ///      minute. Skrajsana vrednost tako fizicno ne more priti na mainnet —
    ///      isti prijem kot pri KYCWhitelistTestnet.
    function zamik() public view virtual returns (uint256) {
        return 48 hours;
    }

    // ── Notranje ────────────────────────────────────────────────────────────

    /// @dev id MORA vsebovati tocne parametre spremembe, sicer bi lahko
    ///      napovedal nedolzno vrednost in izvedel skodljivo.
    function _napovej(bytes32 id, string memory kaj) internal {
        require(izvedljivoOd[id] == 0, "Ze napovedano");
        uint256 od = block.timestamp + zamik();
        izvedljivoOd[id] = od;
        emit SpremembaNapovedana(id, kaj, od, od + ROK);
    }

    function _porabi(bytes32 id, string memory kaj) internal {
        uint256 od = izvedljivoOd[id];
        require(od != 0, "Ni napovedano");
        require(block.timestamp >= od, "Zamik se ni potekel");
        require(block.timestamp <= od + ROK, "Napoved je potekla");
        delete izvedljivoOd[id];
        emit SpremembaIzvedena(id, kaj);
    }

    // ── Javno ───────────────────────────────────────────────────────────────

    /// @notice Preklic napovedane spremembe. Takojsen — premisliti se mora biti
    ///         mogoce hitreje, kot se izvede.
    function prekliciSpremembo(bytes32 id, string calldata kaj) external onlyOwner {
        require(izvedljivoOd[id] != 0, "Ni napovedano");
        delete izvedljivoOd[id];
        emit SpremembaPreklicana(id, kaj);
    }

    /// @notice Stanje napovedi — da ga stran in nadzorni sistem lahko prikazeta.
    function stanjeNapovedi(bytes32 id)
        external
        view
        returns (bool napovedana, uint256 od, uint256 potece, bool izvedljivaZdaj)
    {
        uint256 t = izvedljivoOd[id];
        if (t == 0) return (false, 0, 0, false);
        return (true, t, t + ROK, block.timestamp >= t && block.timestamp <= t + ROK);
    }
}
          

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/Pausable.sol";
import "./AdminZamik.sol";

/**
 * @title Marketplace
 * @notice Primarni in sekundarni trg za RWA tokene na mojdelez.si
 *
 * Tok:
 *   1. Prodajalec listira X RWA tokenov po ceni P USDC/token (opcijsko dovoli ponudbe)
 *   2. Kupec lahko kupi takoj (fiksna cena) ALI odda ponudbo (zaklene USDC v escrow)
 *   3. Prodajalec lahko ponudbo sprejme (prenos RWA kupcu, USDC prodajalcu)
 *   4. Portal zaračuna 0.5% marketplace fee na vsak uspešen nakup/sprejeto ponudbo
 *
 * Opomba: RWAToken._update zaračuna 0.5% transfer fee ob vsakem prenosu RWA tokenov.
 */
interface IKYCWhitelist {
    function isWhitelisted(address account) external view returns (bool);
}

contract Marketplace is Ownable, ReentrancyGuard, Pausable, AdminZamik {
    using SafeERC20 for IERC20;

    // --- Konstante ---
    uint256 public constant MARKETPLACE_FEE_BPS = 50; // 0.5%

    // --- State ---
    address public feeRecipient;
    address public usdc; // USDC contract na PulseChain
    address public kyc;  // KYCWhitelist; ce address(0), je KYC gating IZKLOPLJEN (testno)

    uint256 public nextListingId;
    uint256 public nextOfferId;

    // --- Escrow racunovodstvo (zascita pred dvigom tujih sredstev) ---
    /// @notice USDC, zaklenjen v aktivnih ponudbah kupcev.
    uint256 public escrowedUsdc;
    /// @notice RWA tokeni po naslovu, zaklenjeni v aktivnih listingih.
    mapping(address => uint256) public escrowedRwa;

    struct Listing {
        address seller;
        address rwaToken;       // kateri RWA asset
        uint256 amount;         // koliko RWA tokenov je na prodaj
        uint256 pricePerToken;  // cena v USDC (6 decimals) za 1 RWA token (18 decimals)
        bool active;
        bool isPrimary;         // true = prvotna prodaja od lastnika asseta
        bool acceptsOffers;     // NOVO: true = kupci lahko oddajo svoje ponudbe
    }

    struct Offer {
        address buyer;
        uint256 listingId;
        uint256 amount;         // količina RWA (18 decimals)
        uint256 pricePerToken;  // ponujena cena v USDC (6 decimals)
        uint256 lockedUsdc;     // dejanski znesek zaklenjenega USDC-ja (escrow)
        bool active;            // true = ponudba čaka na odgovor
    }

    mapping(uint256 => Listing) public listings;
    mapping(uint256 => Offer) public offers;

    // rwaToken → seznam aktivnih listing ID-jev
    mapping(address => uint256[]) public tokenListings;

    // listingId → seznam vseh ponudb (offer ID-jev)
    mapping(uint256 => uint256[]) public listingOffers;

    // --- Events ---
    event Listed(
        uint256 indexed listingId,
        address indexed seller,
        address indexed rwaToken,
        uint256 amount,
        uint256 pricePerToken,
        bool isPrimary,
        bool acceptsOffers
    );
    event Purchased(
        uint256 indexed listingId,
        address indexed buyer,
        uint256 amount,
        uint256 totalUsdc,
        uint256 fee
    );
    event ListingCancelled(uint256 indexed listingId, address indexed seller);
    event ListingUpdated(uint256 indexed listingId, uint256 newPrice, uint256 newAmount);
    event FeeRecipientUpdated(address indexed newRecipient);
    // Novi eventi za modul ponudb
    event OfferMade(
        uint256 indexed offerId,
        uint256 indexed listingId,
        address indexed buyer,
        uint256 amount,
        uint256 pricePerToken,
        uint256 lockedUsdc
    );
    event OfferAccepted(
        uint256 indexed offerId,
        uint256 indexed listingId,
        address indexed buyer,
        uint256 amount,
        uint256 lockedUsdc
    );
    event OfferCancelled(uint256 indexed offerId, address indexed by);

    // --- Constructor ---
    constructor(address _usdc, address _feeRecipient, address _kyc) Ownable(msg.sender) {
        require(_usdc != address(0), "USDC zero address");
        require(_feeRecipient != address(0), "Fee recipient zero address");
        usdc = _usdc;
        feeRecipient = _feeRecipient;
        kyc = _kyc; // lahko address(0) = KYC gating izklopljen (testno)
    }

    // --- KYC ---
    /// @notice Ce je kyc nastavljen, mora klicatelj biti na beli listi.
    modifier onlyVerified() {
        require(kyc == address(0) || IKYCWhitelist(kyc).isWhitelisted(msg.sender), "Zahtevan KYC pregled");
        _;
    }

    /// @notice 1. korak: javno napovej zamenjavo KYC liste.
    /// @dev Zamenjava KYC liste je najmocnejsa nastavitev, ki jo owner ima —
    ///      napacna ali podtaknjena lista lahko komurkoli odpre trgovanje ali
    ///      posteno preverjenim zapre. Zato javno in z zamikom.
    function napoviSetKyc(address _kyc) external onlyOwner {
        _napovej(keccak256(abi.encode("setKyc", _kyc)), "Marketplace.setKyc");
    }

    /// @notice 2. korak: izvedi, ko je zamik potekel. Velja SAMO za napovedani naslov.
    function setKyc(address _kyc) external onlyOwner {
        _porabi(keccak256(abi.encode("setKyc", _kyc)), "Marketplace.setKyc");
        kyc = _kyc;
    }

    // --- Listing ---

    /**
     * @notice Ustvari nov listing — primarni (prvotni lastnik) ali sekundarni (kupec naprej prodaja)
     * @param rwaToken naslov RWA ERC-20 kontrakta
     * @param amount število RWA tokenov za prodajo (18 decimals)
     * @param pricePerToken cena v USDC za 1 RWA token (6 decimals)
     * @param isPrimary true = prvotna tokenizacija, false = sekundarni trg
     * @param acceptsOffers true = omogoči zbiranje ponudb na oglasu
     *
     * @dev NAMERNO brez onlyVerified: kdor ima RWA tokene za listanje, je zaradi
     *      KYC restrikcije v RWAToken._update ze preverjen (nepreverjen naslov jih
     *      sploh ne more prejeti). Dodaten gating tu bi bil odvecen, prodajalcu pa
     *      bi lahko zaprl pot do prodaje. Preverjeno s testi 30.7.2026.
     */
    function list(
        address rwaToken,
        uint256 amount,
        uint256 pricePerToken,
        bool isPrimary,
        bool acceptsOffers
    ) external nonReentrant whenNotPaused returns (uint256 listingId) {
        require(rwaToken != address(0), "Invalid token");
        require(amount > 0, "Amount must be > 0");
        require(pricePerToken > 0, "Price must be > 0");

        // Preveri da prodajalec ima dovolj tokenov
        require(
            IERC20(rwaToken).balanceOf(msg.sender) >= amount,
            "Insufficient RWA balance"
        );

        // Escrow: prenesi RWA tokene v Marketplace kontrakt
        // (RWAToken._update bo zaračunal 0.5% transfer fee — tokeni prispejo zmanjšani)
        uint256 beforeBalance = IERC20(rwaToken).balanceOf(address(this));
        IERC20(rwaToken).safeTransferFrom(msg.sender, address(this), amount);
        uint256 afterBalance = IERC20(rwaToken).balanceOf(address(this));
        uint256 received = afterBalance - beforeBalance; // dejanski prejeti znesek (po RWA fee)

        escrowedRwa[rwaToken] += received;

        listingId = nextListingId++;

        listings[listingId] = Listing({
            seller: msg.sender,
            rwaToken: rwaToken,
            amount: received, // dejansko shranjeni tokeni (po 0.5% RWA transfer fee)
            pricePerToken: pricePerToken,
            active: true,
            isPrimary: isPrimary,
            acceptsOffers: acceptsOffers
        });

        tokenListings[rwaToken].push(listingId);

        emit Listed(listingId, msg.sender, rwaToken, received, pricePerToken, isPrimary, acceptsOffers);
    }

    /**
     * @notice Kupi RWA tokene iz listinga (Fiksna cena)
     */
    function buy(uint256 listingId, uint256 amount) external nonReentrant whenNotPaused onlyVerified {
        Listing storage l = listings[listingId];
        require(l.active, "Listing not active");
        require(amount > 0 && amount <= l.amount, "Invalid amount");
        require(msg.sender != l.seller, "Cannot buy your own listing");

        // Izračun USDC stroškov
        uint256 totalUsdc = amount * l.pricePerToken / 1e18;
        require(totalUsdc > 0, "Price too low");

        // Marketplace fee: 0.5% od kupca
        uint256 fee = totalUsdc * MARKETPLACE_FEE_BPS / 10_000;
        uint256 sellerReceives = totalUsdc - fee;

        // Kupec plača USDC
        IERC20(usdc).safeTransferFrom(msg.sender, l.seller, sellerReceives);
        IERC20(usdc).safeTransferFrom(msg.sender, feeRecipient, fee);

        // Posodobi listing
        l.amount -= amount;
        if (l.amount == 0) {
            l.active = false;
        }
        escrowedRwa[l.rwaToken] -= amount;

        // Pošlji RWA tokene kupcu
        IERC20(l.rwaToken).safeTransfer(msg.sender, amount);

        emit Purchased(listingId, msg.sender, amount, totalUsdc, fee);
    }

    /**
     * @notice Prekliči listing in vrni RWA tokene prodajalcu
     */
    function cancelListing(uint256 listingId) external nonReentrant {
        Listing storage l = listings[listingId];
        require(l.active, "Not active");
        require(msg.sender == l.seller || msg.sender == owner(), "Not authorized");

        l.active = false;

        // Vrni tokene prodajalcu
        uint256 vrniAmount = l.amount;
        l.amount = 0;
        escrowedRwa[l.rwaToken] -= vrniAmount;
        IERC20(l.rwaToken).safeTransfer(l.seller, vrniAmount);

        emit ListingCancelled(listingId, l.seller);
    }

    /**
     * @notice Posodobi ceno ali količino obstoječega listinga
     */
    function updateListing(
        uint256 listingId,
        uint256 newPricePerToken,
        uint256 additionalAmount
    ) external nonReentrant {
        Listing storage l = listings[listingId];
        require(l.active, "Not active");
        require(msg.sender == l.seller, "Not seller");
        require(newPricePerToken > 0, "Price must be > 0");

        if (newPricePerToken != l.pricePerToken) {
            l.pricePerToken = newPricePerToken;
        }

        if (additionalAmount > 0) {
            uint256 before = IERC20(l.rwaToken).balanceOf(address(this));
            IERC20(l.rwaToken).safeTransferFrom(msg.sender, address(this), additionalAmount);
            uint256 received = IERC20(l.rwaToken).balanceOf(address(this)) - before;
            l.amount += received;
            escrowedRwa[l.rwaToken] += received;
        }

        emit ListingUpdated(listingId, newPricePerToken, l.amount);
    }

    // --- Modul: Daj Ponudbo (Make an Offer) ---

    /**
     * @notice Kupec odda ponudbo in zaklene svoj USDC v pametno pogodbo
     */
    function makeOffer(uint256 listingId, uint256 amount, uint256 pricePerToken) external nonReentrant whenNotPaused onlyVerified {
        Listing storage l = listings[listingId];
        require(l.active, "Listing not active");
        require(l.acceptsOffers, "Offers not allowed on this listing");
        require(amount > 0 && amount <= l.amount, "Invalid amount");
        require(pricePerToken > 0, "Price must be > 0");
        require(msg.sender != l.seller, "Cannot bid on own listing");

        uint256 totalUsdc = amount * pricePerToken / 1e18;
        require(totalUsdc > 0, "Total USDC too low");

        uint256 offerId = nextOfferId++;

        // Escrow: Zakleni kupčev USDC v pogodbo
        IERC20(usdc).safeTransferFrom(msg.sender, address(this), totalUsdc);
        escrowedUsdc += totalUsdc;

        offers[offerId] = Offer({
            buyer: msg.sender,
            listingId: listingId,
            amount: amount,
            pricePerToken: pricePerToken,
            lockedUsdc: totalUsdc,
            active: true
        });

        listingOffers[listingId].push(offerId);

        emit OfferMade(offerId, listingId, msg.sender, amount, pricePerToken, totalUsdc);
    }

    /**
     * @notice Prodajalec sprejme ponudbo. RWA gre kupcu, USDC prodajalcu.
     */
    function acceptOffer(uint256 offerId) external nonReentrant whenNotPaused {
        Offer storage o = offers[offerId];
        require(o.active, "Offer not active");

        Listing storage l = listings[o.listingId];
        require(l.active, "Listing not active");
        require(msg.sender == l.seller, "Only seller can accept");

        // Če se je listing medtem delno razprodal, ponudba morda presega zalogo
        require(o.amount <= l.amount, "Offer amount exceeds available RWA");

        o.active = false;

        // Izračun feejev (od zaklenjenega USDC zneska)
        uint256 fee = o.lockedUsdc * MARKETPLACE_FEE_BPS / 10_000;
        uint256 sellerReceives = o.lockedUsdc - fee;

        // Posodobi zalogo v listingu
        l.amount -= o.amount;
        if (l.amount == 0) {
            l.active = false;
        }

        // Sprosti escrow racunovodstvo (USDC gre prodajalcu+fee, RWA kupcu)
        escrowedUsdc -= o.lockedUsdc;
        escrowedRwa[l.rwaToken] -= o.amount;

        // 1. Prenos USDC (iz escrowa pogodbe → prodajalcu in marketplaceu)
        IERC20(usdc).safeTransfer(l.seller, sellerReceives);
        IERC20(usdc).safeTransfer(feeRecipient, fee);

        // 2. Prenos RWA (iz escrowa pogodbe → kupcu)
        // Opozorilo: RWAToken pogodba bo kupcu odštela 0.5% pri prejemu,
        // ampak iz Marketplace pogodbe gre točen amount, kar ohranja natančno računovodstvo.
        IERC20(l.rwaToken).safeTransfer(o.buyer, o.amount);

        emit OfferAccepted(offerId, o.listingId, o.buyer, o.amount, o.lockedUsdc);
    }

    /**
     * @notice Kupec umakne ponudbo ali prodajalec zavrne ponudbo (USDC se vrne kupcu)
     */
    function cancelOffer(uint256 offerId) external nonReentrant {
        Offer storage o = offers[offerId];
        require(o.active, "Offer not active");

        Listing storage l = listings[o.listingId];
        // Preklic lahko sproži samo kupec ALI lastnik listinga (kot zavrnitev)
        require(msg.sender == o.buyer || msg.sender == l.seller, "Not authorized to cancel");

        o.active = false;

        // Vrni zaklenjeni USDC kupcu
        escrowedUsdc -= o.lockedUsdc;
        IERC20(usdc).safeTransfer(o.buyer, o.lockedUsdc);

        emit OfferCancelled(offerId, msg.sender);
    }

    // --- View funkcije ---

    /**
     * @notice Vrni vse aktivne listinge za določen RWA token
     */
    function getActiveListings(address rwaToken) external view returns (uint256[] memory activeIds) {
        uint256[] storage all = tokenListings[rwaToken];
        uint256 count = 0;
        for (uint256 i = 0; i < all.length; i++) {
            if (listings[all[i]].active) count++;
        }
        activeIds = new uint256[](count);
        uint256 idx = 0;
        for (uint256 i = 0; i < all.length; i++) {
            if (listings[all[i]].active) {
                activeIds[idx++] = all[i];
            }
        }
    }

    /**
     * @notice Vrni vse aktivne ponudbe za specifičen listing
     */
    function getActiveOffers(uint256 listingId) external view returns (uint256[] memory activeOfferIds) {
        uint256[] storage all = listingOffers[listingId];
        uint256 count = 0;
        for (uint256 i = 0; i < all.length; i++) {
            if (offers[all[i]].active) count++;
        }
        activeOfferIds = new uint256[](count);
        uint256 idx = 0;
        for (uint256 i = 0; i < all.length; i++) {
            if (offers[all[i]].active) {
                activeOfferIds[idx++] = all[i];
            }
        }
    }

    /**
     * @notice Izračun skupnega USDC za fiksni nakup
     */
    function quoteBuy(uint256 listingId, uint256 amount)
        external view
        returns (uint256 totalUsdc, uint256 fee, uint256 sellerReceives)
    {
        Listing storage l = listings[listingId];
        require(l.active, "Not active");
        require(amount <= l.amount, "Exceeds available");
        totalUsdc = amount * l.pricePerToken / 1e18;
        fee = totalUsdc * MARKETPLACE_FEE_BPS / 10_000;
        sellerReceives = totalUsdc - fee;
    }

    /**
     * @notice Izračun stroškov pri oddaji ponudbe brez predhodnega kreiranja
     */
    function quoteOffer(uint256 amount, uint256 pricePerToken)
        external pure
        returns (uint256 totalUsdc, uint256 fee, uint256 sellerReceives)
    {
        totalUsdc = amount * pricePerToken / 1e18;
        fee = totalUsdc * MARKETPLACE_FEE_BPS / 10_000;
        sellerReceives = totalUsdc - fee;
    }

    // --- Admin ---

    function napoviSetFeeRecipient(address _feeRecipient) external onlyOwner {
        require(_feeRecipient != address(0), "Zero address");
        _napovej(keccak256(abi.encode("setFeeRecipient", _feeRecipient)), "Marketplace.setFeeRecipient");
    }

    function setFeeRecipient(address _feeRecipient) external onlyOwner {
        require(_feeRecipient != address(0), "Zero address");
        _porabi(keccak256(abi.encode("setFeeRecipient", _feeRecipient)), "Marketplace.setFeeRecipient");
        feeRecipient = _feeRecipient;
        emit FeeRecipientUpdated(_feeRecipient);
    }

    /**
     * @notice Zamenjava placilnega tokena — dovoljena SAMO, ko ni zaklenjenega USDC.
     * @dev Prej je bila zamenjava mozna kadarkoli: ce bi owner zamenjal USDC med
     *      aktivnimi ponudbami, bi cancelOffer vracal NAPACEN token in kupcev
     *      USDC bi ostal ujet. Zdaj je to onemogoceno.
     */
    function napoviSetUsdc(address _usdc) external onlyOwner {
        require(_usdc != address(0), "Zero address");
        _napovej(keccak256(abi.encode("setUsdc", _usdc)), "Marketplace.setUsdc");
    }

    function setUsdc(address _usdc) external onlyOwner {
        require(_usdc != address(0), "Zero address");
        require(escrowedUsdc == 0, "Escrow ni prazen");
        _porabi(keccak256(abi.encode("setUsdc", _usdc)), "Marketplace.setUsdc");
        usdc = _usdc;
    }

    // --- Zasilna zavora ---

    /**
     * Zakaj ima pravico ustaviti VEC naslovov, spreminjati nastavitve pa samo owner:
     * skoda, ki jo zmore podtaknjen zaustavljalec, je ustavljeno trgovanje —
     * neprijetno, a ni kraje, in owner ga z unpause() takoj razveljavi. Skoda
     * zaradi PREPOZNE zaustavitve pa je lahko trajna. Zato je pri tej edini
     * funkciji hitrost vredna vec kot ozek dostop.
     *
     * Ledger je lahko v sefu; nadzorni sistem in rezervna denarnica ne.
     */
    mapping(address => bool) public jeZaustavljalec;
    event ZaustavljalecSpremenjen(address indexed kdo, bool lahko);

    /// @dev Takojsno v obe smeri. Podelitev je nizko tveganje, odvzem pa mora
    ///      biti hiter — ob razkritem kljucu ga ne smes cakati 48 ur odstraniti.
    function nastaviZaustavljalca(address kdo, bool lahko) external onlyOwner {
        require(kdo != address(0), "Zero address");
        jeZaustavljalec[kdo] = lahko;
        emit ZaustavljalecSpremenjen(kdo, lahko);
    }

    /// @notice Ustavi NOVE posle (list/buy/makeOffer/acceptOffer).
    /// @dev Izhodi (cancelListing, cancelOffer, updateListing) NAMERNO ostanejo
    ///      delujoci tudi med pavzo — uporabnik mora vedno lahko do svojih sredstev.
    function pause() external {
        require(msg.sender == owner() || jeZaustavljalec[msg.sender], "Ni pooblascen za zaustavitev");
        _pause();
    }

    /// @dev Zagon nazaj ostane samo pri ownerju: ustaviti mora biti lahko,
    ///      spet odpreti pa tezko.
    function unpause() external onlyOwner {
        _unpause();
    }

    /**
     * @notice Emergency: owner lahko dvigne SAMO presezek nad zaklenjenimi sredstvi
     *         (npr. pomotoma poslane tokene).
     * @dev POPRAVLJENO (30.7.2026): prej je ta funkcija lahko dvignila tudi USDC,
     *      zaklenjen v ponudbah kupcev, in RWA iz aktivnih listingov — torej TUJA
     *      sredstva. Zdaj escrow racunovodstvo (escrowedUsdc / escrowedRwa) tvori
     *      spodnjo mejo, ki je owner ne more prebiti.
     */
    function emergencyWithdraw(address token, uint256 amount) external onlyOwner {
        uint256 zaklenjeno = token == usdc ? escrowedUsdc : escrowedRwa[token];
        uint256 stanje = IERC20(token).balanceOf(address(this));
        require(stanje >= zaklenjeno, "Nekonsistenten escrow");
        require(stanje - zaklenjeno >= amount, "Presega prosti presezek");
        IERC20(token).safeTransfer(owner(), amount);
    }

    /// @notice Onemogoceno: pomotoma poslan renounceOwnership() bi trajno ubil
    ///         pause(), fee nastavitve in KYC preklop.
    function renounceOwnership() public pure override {
        revert("Renounce onemogocen");
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC20.sol)

pragma solidity >=0.4.16;

import {IERC20} from "../token/ERC20/IERC20.sol";
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.5.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.20;

import {IERC20} from "../IERC20.sol";
import {IERC1363} from "../../../interfaces/IERC1363.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC-20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    /**
     * @dev An operation with an ERC-20 token failed.
     */
    error SafeERC20FailedOperation(address token);

    /**
     * @dev Indicates a failed `decreaseAllowance` request.
     */
    error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease);

    /**
     * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        if (!_safeTransfer(token, to, value, true)) {
            revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
     * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
     */
    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        if (!_safeTransferFrom(token, from, to, value, true)) {
            revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Variant of {safeTransfer} that returns a bool instead of reverting if the operation is not successful.
     */
    function trySafeTransfer(IERC20 token, address to, uint256 value) internal returns (bool) {
        return _safeTransfer(token, to, value, false);
    }

    /**
     * @dev Variant of {safeTransferFrom} that returns a bool instead of reverting if the operation is not successful.
     */
    function trySafeTransferFrom(IERC20 token, address from, address to, uint256 value) internal returns (bool) {
        return _safeTransferFrom(token, from, to, value, false);
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     *
     * IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
     * smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
     * this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
     * that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
     */
    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 oldAllowance = token.allowance(address(this), spender);
        forceApprove(token, spender, oldAllowance + value);
    }

    /**
     * @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no
     * value, non-reverting calls are assumed to be successful.
     *
     * IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
     * smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
     * this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
     * that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
     */
    function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal {
        unchecked {
            uint256 currentAllowance = token.allowance(address(this), spender);
            if (currentAllowance < requestedDecrease) {
                revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease);
            }
            forceApprove(token, spender, currentAllowance - requestedDecrease);
        }
    }

    /**
     * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
     * to be set to zero before setting it to a non-zero value, such as USDT.
     *
     * NOTE: If the token implements ERC-7674, this function will not modify any temporary allowance. This function
     * only sets the "standard" allowance. Any temporary allowance will remain active, in addition to the value being
     * set here.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        if (!_safeApprove(token, spender, value, false)) {
            if (!_safeApprove(token, spender, 0, true)) revert SafeERC20FailedOperation(address(token));
            if (!_safeApprove(token, spender, value, true)) revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Performs an {ERC1363} transferAndCall, with a fallback to the simple {ERC20} transfer if the target has no
     * code. This can be used to implement an {ERC721}-like safe transfer that relies on {ERC1363} checks when
     * targeting contracts.
     *
     * Reverts if the returned value is other than `true`.
     */
    function transferAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
        if (to.code.length == 0) {
            safeTransfer(token, to, value);
        } else if (!token.transferAndCall(to, value, data)) {
            revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Performs an {ERC1363} transferFromAndCall, with a fallback to the simple {ERC20} transferFrom if the target
     * has no code. This can be used to implement an {ERC721}-like safe transfer that relies on {ERC1363} checks when
     * targeting contracts.
     *
     * Reverts if the returned value is other than `true`.
     */
    function transferFromAndCallRelaxed(
        IERC1363 token,
        address from,
        address to,
        uint256 value,
        bytes memory data
    ) internal {
        if (to.code.length == 0) {
            safeTransferFrom(token, from, to, value);
        } else if (!token.transferFromAndCall(from, to, value, data)) {
            revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Performs an {ERC1363} approveAndCall, with a fallback to the simple {ERC20} approve if the target has no
     * code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
     * targeting contracts.
     *
     * NOTE: When the recipient address (`to`) has no code (i.e. is an EOA), this function behaves as {forceApprove}.
     * Oppositely, when the recipient address (`to`) has code, this function only attempts to call {ERC1363-approveAndCall}
     * once without retrying, and relies on the returned value to be true.
     *
     * Reverts if the returned value is other than `true`.
     */
    function approveAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
        if (to.code.length == 0) {
            forceApprove(token, to, value);
        } else if (!token.approveAndCall(to, value, data)) {
            revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Imitates a Solidity `token.transfer(to, value)` call, relaxing the requirement on the return value: the
     * return value is optional (but if data is returned, it must not be false).
     *
     * @param token The token targeted by the call.
     * @param to The recipient of the tokens
     * @param value The amount of token to transfer
     * @param bubble Behavior switch if the transfer call reverts: bubble the revert reason or return a false boolean.
     */
    function _safeTransfer(IERC20 token, address to, uint256 value, bool bubble) private returns (bool success) {
        bytes4 selector = IERC20.transfer.selector;

        assembly ("memory-safe") {
            let fmp := mload(0x40)
            mstore(0x00, selector)
            mstore(0x04, and(to, shr(96, not(0))))
            mstore(0x24, value)
            success := call(gas(), token, 0, 0x00, 0x44, 0x00, 0x20)
            // if call success and return is true, all is good.
            // otherwise (not success or return is not true), we need to perform further checks
            if iszero(and(success, eq(mload(0x00), 1))) {
                // if the call was a failure and bubble is enabled, bubble the error
                if and(iszero(success), bubble) {
                    returndatacopy(fmp, 0x00, returndatasize())
                    revert(fmp, returndatasize())
                }
                // if the return value is not true, then the call is only successful if:
                // - the token address has code
                // - the returndata is empty
                success := and(success, and(iszero(returndatasize()), gt(extcodesize(token), 0)))
            }
            mstore(0x40, fmp)
        }
    }

    /**
     * @dev Imitates a Solidity `token.transferFrom(from, to, value)` call, relaxing the requirement on the return
     * value: the return value is optional (but if data is returned, it must not be false).
     *
     * @param token The token targeted by the call.
     * @param from The sender of the tokens
     * @param to The recipient of the tokens
     * @param value The amount of token to transfer
     * @param bubble Behavior switch if the transfer call reverts: bubble the revert reason or return a false boolean.
     */
    function _safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value,
        bool bubble
    ) private returns (bool success) {
        bytes4 selector = IERC20.transferFrom.selector;

        assembly ("memory-safe") {
            let fmp := mload(0x40)
            mstore(0x00, selector)
            mstore(0x04, and(from, shr(96, not(0))))
            mstore(0x24, and(to, shr(96, not(0))))
            mstore(0x44, value)
            success := call(gas(), token, 0, 0x00, 0x64, 0x00, 0x20)
            // if call success and return is true, all is good.
            // otherwise (not success or return is not true), we need to perform further checks
            if iszero(and(success, eq(mload(0x00), 1))) {
                // if the call was a failure and bubble is enabled, bubble the error
                if and(iszero(success), bubble) {
                    returndatacopy(fmp, 0x00, returndatasize())
                    revert(fmp, returndatasize())
                }
                // if the return value is not true, then the call is only successful if:
                // - the token address has code
                // - the returndata is empty
                success := and(success, and(iszero(returndatasize()), gt(extcodesize(token), 0)))
            }
            mstore(0x40, fmp)
            mstore(0x60, 0)
        }
    }

    /**
     * @dev Imitates a Solidity `token.approve(spender, value)` call, relaxing the requirement on the return value:
     * the return value is optional (but if data is returned, it must not be false).
     *
     * @param token The token targeted by the call.
     * @param spender The spender of the tokens
     * @param value The amount of token to transfer
     * @param bubble Behavior switch if the transfer call reverts: bubble the revert reason or return a false boolean.
     */
    function _safeApprove(IERC20 token, address spender, uint256 value, bool bubble) private returns (bool success) {
        bytes4 selector = IERC20.approve.selector;

        assembly ("memory-safe") {
            let fmp := mload(0x40)
            mstore(0x00, selector)
            mstore(0x04, and(spender, shr(96, not(0))))
            mstore(0x24, value)
            success := call(gas(), token, 0, 0x00, 0x44, 0x00, 0x20)
            // if call success and return is true, all is good.
            // otherwise (not success or return is not true), we need to perform further checks
            if iszero(and(success, eq(mload(0x00), 1))) {
                // if the call was a failure and bubble is enabled, bubble the error
                if and(iszero(success), bubble) {
                    returndatacopy(fmp, 0x00, returndatasize())
                    revert(fmp, returndatasize())
                }
                // if the return value is not true, then the call is only successful if:
                // - the token address has code
                // - the returndata is empty
                success := and(success, and(iszero(returndatasize()), gt(extcodesize(token), 0)))
            }
            mstore(0x40, fmp)
        }
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (utils/introspection/IERC165.sol)

pragma solidity >=0.4.16;

/**
 * @dev Interface of the ERC-165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[ERC].
 *
 * 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[ERC 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);
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.5.0) (utils/ReentrancyGuard.sol)

pragma solidity ^0.8.20;

import {StorageSlot} from "./StorageSlot.sol";

/**
 * @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 EIP-1153 (transient storage) is available on the chain you're deploying at,
 * consider using {ReentrancyGuardTransient} instead.
 *
 * 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].
 *
 * IMPORTANT: Deprecated. This storage-based reentrancy guard will be removed and replaced
 * by the {ReentrancyGuardTransient} variant in v6.0.
 *
 * @custom:stateless
 */
abstract contract ReentrancyGuard {
    using StorageSlot for bytes32;

    // keccak256(abi.encode(uint256(keccak256("openzeppelin.storage.ReentrancyGuard")) - 1)) & ~bytes32(uint256(0xff))
    bytes32 private constant REENTRANCY_GUARD_STORAGE =
        0x9b779b17422d0df92223018b32b4d1fa46e071723d6817e2486d003becc55f00;

    // 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;

    /**
     * @dev Unauthorized reentrant call.
     */
    error ReentrancyGuardReentrantCall();

    constructor() {
        _reentrancyGuardStorageSlot().getUint256Slot().value = 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() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    /**
     * @dev A `view` only version of {nonReentrant}. Use to block view functions
     * from being called, preventing reading from inconsistent contract state.
     *
     * CAUTION: This is a "view" modifier and does not change the reentrancy
     * status. Use it only on view functions. For payable or non-payable functions,
     * use the standard {nonReentrant} modifier instead.
     */
    modifier nonReentrantView() {
        _nonReentrantBeforeView();
        _;
    }

    function _nonReentrantBeforeView() private view {
        if (_reentrancyGuardEntered()) {
            revert ReentrancyGuardReentrantCall();
        }
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be NOT_ENTERED
        _nonReentrantBeforeView();

        // Any calls to nonReentrant after this point will fail
        _reentrancyGuardStorageSlot().getUint256Slot().value = ENTERED;
    }

    function _nonReentrantAfter() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _reentrancyGuardStorageSlot().getUint256Slot().value = NOT_ENTERED;
    }

    /**
     * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
     * `nonReentrant` function in the call stack.
     */
    function _reentrancyGuardEntered() internal view returns (bool) {
        return _reentrancyGuardStorageSlot().getUint256Slot().value == ENTERED;
    }

    function _reentrancyGuardStorageSlot() internal pure virtual returns (bytes32) {
        return REENTRANCY_GUARD_STORAGE;
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.3.0) (utils/Pausable.sol)

pragma solidity ^0.8.20;

import {Context} from "../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 {
    bool private _paused;

    /**
     * @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);

    /**
     * @dev The operation failed because the contract is paused.
     */
    error EnforcedPause();

    /**
     * @dev The operation failed because the contract is not paused.
     */
    error ExpectedPause();

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

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }

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

    /**
     * @dev Throws if the contract is paused.
     */
    function _requireNotPaused() internal view virtual {
        if (paused()) {
            revert EnforcedPause();
        }
    }

    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        if (!paused()) {
            revert ExpectedPause();
        }
    }

    /**
     * @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());
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)

pragma solidity ^0.8.20;

import {Context} from "../utils/Context.sol";

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

    /**
     * @dev The caller account is not authorized to perform an operation.
     */
    error OwnableUnauthorizedAccount(address account);

    /**
     * @dev The owner is not a valid owner account. (eg. `address(0)`)
     */
    error OwnableInvalidOwner(address owner);

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

    /**
     * @dev Initializes the contract setting the address provided by the deployer as the initial owner.
     */
    constructor(address initialOwner) {
        if (initialOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(initialOwner);
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

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

    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        if (owner() != _msgSender()) {
            revert OwnableUnauthorizedAccount(_msgSender());
        }
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby disabling any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        if (newOwner == address(0)) {
            revert OwnableInvalidOwner(address(0));
        }
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}