Contract Address Details

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

import "https://raw.githubusercontent.com/OpenZeppelin/openzeppelin-contracts/v5.0.2/contracts/utils/ReentrancyGuard.sol";
import "https://raw.githubusercontent.com/OpenZeppelin/openzeppelin-contracts/v5.0.2/contracts/access/Ownable.sol";
import "https://raw.githubusercontent.com/OpenZeppelin/openzeppelin-contracts/v5.0.2/contracts/token/ERC20/IERC20.sol";
import "https://raw.githubusercontent.com/OpenZeppelin/openzeppelin-contracts/v5.0.2/contracts/token/ERC20/utils/SafeERC20.sol";
import "https://raw.githubusercontent.com/OpenZeppelin/openzeppelin-contracts/v5.0.2/contracts/utils/cryptography/ECDSA.sol";
import "https://raw.githubusercontent.com/OpenZeppelin/openzeppelin-contracts/v5.0.2/contracts/utils/cryptography/MessageHashUtils.sol";

// ─────────────────────────────────────────────────────────────────────────────
//  StreamingRewardsV6
//
//  WHAT CHANGED FROM V5
//  ─────────────────────
//  V5 managed 17 token reward pools with price feeds, pending rewards,
//  claim functions, and runway monitoring. All of that is removed.
//
//  V6 has one job on each stream update: call ArtistTokenFactory.mintForStream().
//  The factory handles all token minting, creator payments, and LP fees.
//
//  Everything else is identical to V5:
//    • Streak system (shields, milestones, celebrations)
//    • Dedicated Listener (total seconds per artist, frame tiers)
//    • Weekly MEFI jackpot (competitive streaming leaderboard)
//    • Shield purchases (MEFI → jackpot pool)
//    • MysteryBoxV3 ABI compatibility (getStreakInfo 10-field layout)
//    • Oracle signature verification with 48h signer timelock
//    • Pause system
//    • Migration from V5
//
//  ORACLE FLOW
//  ─────────────
//  Every ~60s oracle calls updateStream(user, deltaSeconds, boostedDelta,
//    creatorAddress, trackId, sessionId, nonce, signature)
//  Contract:
//    1. Verifies signature
//    2. Calls factory.mintForStream(user, creatorAddress, boostedDelta)
//    3. Updates weeklyBoostedSeconds[user]
//    4. Updates streak + dedicated listener
//
//  MEFI JACKPOT FLOW
//  ─────────────────
//  BatchBuyer sends MEFI → notifyMyfiReceived() or fundJackpot()
//  Oracle calls distributeWeeklyJackpot() each Sunday
//  Top streamers by weeklyBoostedSeconds win MEFI prizes
// ─────────────────────────────────────────────────────────────────────────────

interface IKEYStaking {
    function getBoostBps(address user) external view returns (uint256);
    function getTierId(address user) external view returns (uint8);
}

interface IArtistTokenFactory {
    function mintForStream(address user, address artist, uint256 boostedDelta) external;
}

contract StreamingRewardsV6 is Ownable, ReentrancyGuard {
    using SafeERC20 for IERC20;
    using ECDSA for bytes32;
    using MessageHashUtils for bytes32;

    // ─── Constants ────────────────────────────────────────────────────────────

    uint256 public constant BPS_DENOMINATOR  = 10000;
    uint256 public constant SECONDS_PER_WEEK = 604800;

    // ─── Configurable ─────────────────────────────────────────────────────────

    uint256 public signatureWindow   = 600;    // 10 min replay window
    uint256 public oracleChangeDelay = 172800; // 48h timelock

    // ─── User State ───────────────────────────────────────────────────────────

    mapping(address => uint256) public weeklyBoostedSeconds;
    mapping(address => uint256) public totalLifetimeBoostedSeconds;
    mapping(address => uint256) public userNonces;

    // ─── Dedicated Listener ───────────────────────────────────────────────────
    // Total seconds streamed per (user, artist) — cumulative, never resets.
    // Drives tiered avatar frames the artist customises for their fans.
    // Tiers match KEY staking names:
    //   Fan (1h) → Collector (5h) → Curator (20h) → Legend (100h)

    mapping(address => mapping(address => uint256)) public artistTotalSeconds;

    mapping(address => mapping(address => bool)) public dedicatedFanClaimed;
    mapping(address => mapping(address => bool)) public dedicatedCollectorClaimed;
    mapping(address => mapping(address => bool)) public dedicatedCuratorClaimed;
    mapping(address => mapping(address => bool)) public dedicatedLegendClaimed;

    uint256 public dedicatedFanThreshold       =   3_600;
    uint256 public dedicatedCollectorThreshold =  18_000;
    uint256 public dedicatedCuratorThreshold   =  72_000;
    uint256 public dedicatedLegendThreshold    = 360_000;

    mapping(address => address) public activeFrameArtist;
    mapping(address => uint8)   public activeFrameTier;

    // ─── Streak ───────────────────────────────────────────────────────────────

    struct StreakInfo {
        uint256 streakDays;
        uint256 lastStreamDay;
        uint256 missedDays;
        uint256 shields;
        uint256 purchasedShieldsCount;
        bool    milestone7Claimed;
        bool    milestone30Claimed;
        bool    milestone90Claimed;
        bool    milestone180Claimed;
    }
    mapping(address => StreakInfo) public streaks;

    uint256 public shieldCostMyfi = 10 * 1e18;
    uint256 public maxShields     = 3;

    // ─── Weekly Jackpot ───────────────────────────────────────────────────────

    uint256 public weekNumber;
    uint256 public lastJackpotSettlement;
    uint256 public minJackpotSize;

    address public jackpotToken; // MEFI

    /// @notice Live MEFI jackpot balance — reads contract balance directly.
    ///         BatchBuyer raw transfers and graduation payments count automatically.
    function jackpotPool() public view returns (uint256) {
        if (jackpotToken == address(0)) return 0;
        return IERC20(jackpotToken).balanceOf(address(this));
    }

    uint256 public legendPoolBps = 500;
    address[] public legendStakerList;
    mapping(address => bool) public isLegendStaker;
    uint8 public legendTierId = 3;

    // ─── External Contracts ───────────────────────────────────────────────────

    IKEYStaking         public keyStaking;
    IArtistTokenFactory public artistFactory;

    // ─── Oracle Signer ────────────────────────────────────────────────────────

    address public oracleSigner;
    address public pendingOracleSigner;
    uint256 public oracleSignerChangeTime;

    // ─── Pause ────────────────────────────────────────────────────────────────

    bool public paused;

    // ─── Events ───────────────────────────────────────────────────────────────

    event StreamUpdated(address indexed user, uint256 boostedDelta, uint256 weeklyTotal);
    event FactoryMintCalled(address indexed user, address indexed artist, uint256 boostedDelta);
    event FactoryMintFailed(address indexed user, address indexed artist, string reason);

    event WeeklyJackpotDistributed(address[] winners, uint256[] amounts, uint256 weekNumber, uint256 totalPaid);
    event WeeklyJackpotRolledOver(uint256 amount, uint256 newTotal);
    event JackpotFunded(uint256 amount, uint256 newTotal);
    event ShieldPurchased(address indexed user, uint256 cost, uint256 newShieldCount);

    event StreakUpdated(address indexed user, uint256 streakDays);
    event StreakMilestone(address indexed user, uint256 day, uint256 shieldsEarned);
    event StreakCelebration(address indexed user, uint256 day);

    event DedicatedListenerFrame(address indexed user, address indexed artist, uint8 frameTier, uint256 totalSeconds, uint256 timestamp);
    event ActiveFrameSet(address indexed user, address indexed artist, uint8 frameTier);
    event DedicatedListener(address indexed user, address indexed topArtist, uint256 streakDays, uint256 timestamp);
    event TopArtistsUpdated(address indexed user, address artist1, address artist2, address artist3, uint256 timestamp);

    event OracleSignerProposed(address indexed proposed, uint256 executeAfter);
    event OracleSignerChanged(address indexed oldSigner, address indexed newSigner);
    event MigrationLocked();

    // ─── Constructor ──────────────────────────────────────────────────────────

    constructor(
        address _oracleSigner,
        address _keyStaking,
        address _artistFactory,
        address _jackpotToken,
        address initialOwner
    ) Ownable(initialOwner) {
        require(_oracleSigner != address(0), "Zero oracle");
        oracleSigner          = _oracleSigner;
        keyStaking            = IKEYStaking(_keyStaking);
        artistFactory         = IArtistTokenFactory(_artistFactory);
        jackpotToken          = _jackpotToken;
        lastJackpotSettlement = block.timestamp;
        weekNumber            = 1;
        minJackpotSize        = 1e18;
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  ORACLE — updateStream
    // ─────────────────────────────────────────────────────────────────────────

    /**
     * @notice Oracle calls this every ~60s per active streaming session.
     *
     * @param user           Streamer wallet
     * @param deltaSeconds   Raw seconds since last update
     * @param boostedDelta   deltaSeconds × KEY tier multiplier (oracle-computed)
     * @param creatorAddress Creator of the currently playing track
     * @param trackId        keccak256(trackUUID) — for future Song Drops
     * @param sessionId      Unique per-session identifier
     * @param nonce          userNonces[user] + 1
     * @param signature      Oracle signature over all params
     */
    function updateStream(
        address user,
        uint256 deltaSeconds,
        uint256 boostedDelta,
        address creatorAddress,
        bytes32 trackId,
        uint256 sessionId,
        uint256 nonce,
        bytes   calldata signature
    ) external nonReentrant {
        require(!paused,                       "Paused");
        require(boostedDelta > 0,              "Zero delta");
        require(nonce == userNonces[user] + 1, "Bad nonce");

        _verifySignature(
            user, deltaSeconds, boostedDelta,
            creatorAddress, trackId, sessionId, nonce, signature
        );

        userNonces[user] = nonce;

        // Call factory to mint artist tokens — try/catch so a factory
        // failure never blocks streak or jackpot updates
        if (address(artistFactory) != address(0) && creatorAddress != address(0)) {
            try artistFactory.mintForStream(user, creatorAddress, boostedDelta) {
                emit FactoryMintCalled(user, creatorAddress, boostedDelta);
            } catch Error(string memory reason) {
                emit FactoryMintFailed(user, creatorAddress, reason);
            } catch {
                emit FactoryMintFailed(user, creatorAddress, "Unknown");
            }
        }

        // Weekly leaderboard tracking
        weeklyBoostedSeconds[user]        += boostedDelta;
        totalLifetimeBoostedSeconds[user] += boostedDelta;

        // Streak + dedicated listener
        _updateStreak(user, deltaSeconds, creatorAddress);

        emit StreamUpdated(user, boostedDelta, weeklyBoostedSeconds[user]);
    }

    function _verifySignature(
        address user,
        uint256 deltaSeconds,
        uint256 boostedDelta,
        address creatorAddress,
        bytes32 trackId,
        uint256 sessionId,
        uint256 nonce,
        bytes calldata signature
    ) internal view {
        uint256 window  = block.timestamp / signatureWindow;
        bytes32 msgHash = keccak256(abi.encode(
            user, deltaSeconds, boostedDelta,
            creatorAddress, trackId,
            sessionId, nonce, window
        ));
        address signer = msgHash.toEthSignedMessageHash().recover(signature);
        require(signer == oracleSigner, "Bad sig");
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  STREAK
    // ─────────────────────────────────────────────────────────────────────────

    function _updateStreak(address user, uint256 deltaSeconds, address creatorAddress) internal {
        if (deltaSeconds == 0) return;

        StreakInfo storage s = streaks[user];
        uint256 today = block.timestamp / 86400;

        if (s.lastStreamDay == today) {
            if (creatorAddress != address(0))
                _updateDedicatedListener(user, creatorAddress, deltaSeconds);
            return;
        }

        if (s.lastStreamDay == 0) {
            s.streakDays = 1;
        } else if (s.lastStreamDay == today - 1) {
            s.streakDays++;
        } else {
            uint256 daysMissed = today - s.lastStreamDay - 1;
            if (s.shields > 0 && daysMissed == 1) {
                s.shields--;
                s.streakDays++;
            } else {
                s.missedDays += daysMissed;
                s.streakDays = 1;
            }
        }

        s.lastStreamDay = today;
        _checkStreakMilestones(user, s.streakDays);

        if (creatorAddress != address(0))
            _updateDedicatedListener(user, creatorAddress, deltaSeconds);

        emit StreakUpdated(user, s.streakDays);
    }

    function _checkStreakMilestones(address user, uint256 day) internal {
        StreakInfo storage s = streaks[user];
        uint256 earned = 0;
        if (day == 7   && !s.milestone7Claimed)   { s.milestone7Claimed   = true; earned++; }
        if (day == 30  && !s.milestone30Claimed)  { s.milestone30Claimed  = true; earned++; }
        if (day == 90  && !s.milestone90Claimed)  { s.milestone90Claimed  = true; earned++; }
        if (day == 180 && !s.milestone180Claimed) { s.milestone180Claimed = true; earned++; }
        if (earned > 0) {
            s.shields += earned;
            if (s.shields > maxShields) s.shields = maxShields;
            emit StreakMilestone(user, day, earned);
        }
        if (day == 45 || day == 60) {
            emit StreakCelebration(user, day);
        }
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  DEDICATED LISTENER
    // ─────────────────────────────────────────────────────────────────────────

    function _updateDedicatedListener(address user, address artist, uint256 deltaSeconds) internal {
        if (artist == address(0) || deltaSeconds == 0) return;
        artistTotalSeconds[user][artist] += deltaSeconds;
        _checkDedicatedMilestones(user, artist, artistTotalSeconds[user][artist]);
    }

    function _checkDedicatedMilestones(address user, address artist, uint256 total) internal {
        if (total >= dedicatedFanThreshold && !dedicatedFanClaimed[user][artist]) {
            dedicatedFanClaimed[user][artist] = true;
            emit DedicatedListenerFrame(user, artist, 0, total, block.timestamp);
        }
        if (total >= dedicatedCollectorThreshold && !dedicatedCollectorClaimed[user][artist]) {
            dedicatedCollectorClaimed[user][artist] = true;
            emit DedicatedListenerFrame(user, artist, 1, total, block.timestamp);
        }
        if (total >= dedicatedCuratorThreshold && !dedicatedCuratorClaimed[user][artist]) {
            dedicatedCuratorClaimed[user][artist] = true;
            emit DedicatedListenerFrame(user, artist, 2, total, block.timestamp);
        }
        if (total >= dedicatedLegendThreshold && !dedicatedLegendClaimed[user][artist]) {
            dedicatedLegendClaimed[user][artist] = true;
            emit DedicatedListenerFrame(user, artist, 3, total, block.timestamp);
        }
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  SHIELD PURCHASE
    // ─────────────────────────────────────────────────────────────────────────

    function purchaseShield(uint256 myfiAmount) external nonReentrant returns (uint256 newShieldCount) {
        require(!paused,                              "Paused");
        require(address(jackpotToken) != address(0), "MEFI not set");
        require(myfiAmount == shieldCostMyfi,         "Wrong amount");

        StreakInfo storage s = streaks[msg.sender];
        require(s.shields < maxShields, "Max shields held");

        IERC20(jackpotToken).safeTransferFrom(msg.sender, address(this), myfiAmount);

        s.shields++;
        s.purchasedShieldsCount++;
        newShieldCount = s.shields;

        emit ShieldPurchased(msg.sender, myfiAmount, newShieldCount);
        emit JackpotFunded(myfiAmount, jackpotPool());
    }

    function getShieldCost() external view returns (uint256) { return shieldCostMyfi; }

    // ─────────────────────────────────────────────────────────────────────────
    //  WEEKLY JACKPOT
    // ─────────────────────────────────────────────────────────────────────────

    /**
     * @notice Oracle settles the weekly jackpot each Sunday.
     *         5% → Legend KEY stakers equally
     *         95% → top streamers by boostedSeconds (oracle-ranked)
     *         ALL participants' weeklyBoostedSeconds reset.
     */
    function distributeWeeklyJackpot(
        address[] calldata winners,
        uint256[] calldata amounts,
        address[] calldata allParticipants
    ) external nonReentrant {
        require(msg.sender == oracleSigner || msg.sender == owner(), "Auth");
        require(winners.length == amounts.length, "Mismatch");
        require(winners.length > 0,               "No winners");
        require(block.timestamp >= lastJackpotSettlement + 6 days, "Too soon");

        // Always reset all participants before pool check (prevents carry-forward bug)
        for (uint256 i = 0; i < allParticipants.length; i++) {
            weeklyBoostedSeconds[allParticipants[i]] = 0;
        }

        uint256 pool = jackpotPool();
        if (pool < minJackpotSize) {
            emit WeeklyJackpotRolledOver(pool, pool);
            lastJackpotSettlement = block.timestamp;
            weekNumber++;
            return;
        }

        IERC20 mefi = IERC20(jackpotToken);

        // Legend staker split (5%)
        uint256 legendPool_       = (pool * legendPoolBps) / BPS_DENOMINATOR;
        uint256 activeLegendCount = _countActiveLegendStakers();
        if (legendPool_ > 0 && activeLegendCount > 0) {
            uint256 perLegend = legendPool_ / activeLegendCount;
            if (perLegend > 0) {
                for (uint256 i = 0; i < legendStakerList.length; i++) {
                    if (!_isActiveLegend(legendStakerList[i])) continue;
                    mefi.safeTransfer(legendStakerList[i], perLegend);
                }
            }
        }

        // Competitive payout
        uint256 totalPayout = 0;
        for (uint256 i = 0; i < amounts.length; i++) totalPayout += amounts[i];
        require(totalPayout <= pool, "Exceeds pool");

        for (uint256 i = 0; i < winners.length; i++) {
            if (amounts[i] > 0 && winners[i] != address(0)) {
                mefi.safeTransfer(winners[i], amounts[i]);
            }
        }

        emit WeeklyJackpotDistributed(winners, amounts, weekNumber, totalPayout);
        lastJackpotSettlement = block.timestamp;
        weekNumber++;
    }

    function _countActiveLegendStakers() internal view returns (uint256 count) {
        for (uint256 i = 0; i < legendStakerList.length; i++) {
            if (_isActiveLegend(legendStakerList[i])) count++;
        }
    }

    function _isActiveLegend(address staker) internal view returns (bool) {
        if (address(keyStaking) == address(0)) return false;
        try keyStaking.getTierId(staker) returns (uint8 tierId) {
            return tierId == legendTierId;
        } catch { return false; }
    }

    function syncLegendStakers(address[] calldata stakers) external {
        require(msg.sender == oracleSigner || msg.sender == owner(), "Auth");
        for (uint256 i = 0; i < legendStakerList.length; i++) {
            isLegendStaker[legendStakerList[i]] = false;
        }
        delete legendStakerList;
        for (uint256 i = 0; i < stakers.length; i++) {
            if (!isLegendStaker[stakers[i]]) {
                legendStakerList.push(stakers[i]);
                isLegendStaker[stakers[i]] = true;
            }
        }
    }

    function fundJackpot(uint256 amount) external nonReentrant {
        IERC20(jackpotToken).safeTransferFrom(msg.sender, address(this), amount);
        emit JackpotFunded(amount, jackpotPool());
    }

    function notifyMyfiReceived(uint256 amount) external nonReentrant {
        require(msg.sender == oracleSigner || msg.sender == owner(), "Auth");
        // MEFI already transferred to this contract by caller
        emit JackpotFunded(amount, jackpotPool());
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  DEDICATED LISTENER — oracle + user functions
    // ─────────────────────────────────────────────────────────────────────────

    function recordTopArtists(
        address user,
        address artist1,
        address artist2,
        address artist3
    ) external {
        require(msg.sender == oracleSigner || msg.sender == owner(), "Auth");
        require(artist1 != address(0), "Must have at least one artist");
        uint256 sd = streaks[user].streakDays;
        emit TopArtistsUpdated(user, artist1, artist2, artist3, block.timestamp);
        emit DedicatedListener(user, artist1, sd, block.timestamp);
        if (artist2 != address(0)) emit DedicatedListener(user, artist2, sd, block.timestamp);
        if (artist3 != address(0)) emit DedicatedListener(user, artist3, sd, block.timestamp);
    }

    function recordDedicatedListener(address user, address topArtist) external {
        require(msg.sender == oracleSigner || msg.sender == owner(), "Auth");
        require(topArtist != address(0), "Bad artist");
        emit DedicatedListener(user, topArtist, streaks[user].streakDays, block.timestamp);
    }

    function getDedicatedListenerInfo(address user, address artist) external view returns (
        uint256 totalSeconds,
        bool    fanEarned,
        bool    collectorEarned,
        bool    curatorEarned,
        bool    legendEarned
    ) {
        return (
            artistTotalSeconds[user][artist],
            dedicatedFanClaimed[user][artist],
            dedicatedCollectorClaimed[user][artist],
            dedicatedCuratorClaimed[user][artist],
            dedicatedLegendClaimed[user][artist]
        );
    }

    function setActiveFrame(address artist, uint8 frameTier) external {
        require(frameTier <= 3, "Invalid tier");
        if (artist == address(0)) {
            activeFrameArtist[msg.sender] = address(0);
            activeFrameTier[msg.sender]   = 0;
            emit ActiveFrameSet(msg.sender, address(0), 0);
            return;
        }
        if (frameTier == 0) require(dedicatedFanClaimed[msg.sender][artist],       "Fan frame not earned");
        if (frameTier == 1) require(dedicatedCollectorClaimed[msg.sender][artist], "Collector frame not earned");
        if (frameTier == 2) require(dedicatedCuratorClaimed[msg.sender][artist],   "Curator frame not earned");
        if (frameTier == 3) require(dedicatedLegendClaimed[msg.sender][artist],    "Legend frame not earned");
        activeFrameArtist[msg.sender] = artist;
        activeFrameTier[msg.sender]   = frameTier;
        emit ActiveFrameSet(msg.sender, artist, frameTier);
    }

    function getActiveFrame(address user) external view returns (address artist, uint8 frameTier) {
        return (activeFrameArtist[user], activeFrameTier[user]);
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  VIEW FUNCTIONS
    // ─────────────────────────────────────────────────────────────────────────

    /**
     * @notice 10-field streak info — preserves MysteryBoxV3 ABI compatibility.
     *         Field 1 (streakMultiplierBps) always returns 0 — deprecated.
     */
    function getStreakInfo(address user) external view returns (
        uint256 streakDays,
        uint256 streakMultiplierBps,
        uint256 lastStreamDay,
        uint256 missedDays,
        uint256 shields,
        uint256 purchasedShieldsCount,
        bool    milestone7Claimed,
        bool    milestone30Claimed,
        bool    milestone90Claimed,
        bool    milestone180Claimed
    ) {
        StreakInfo storage s = streaks[user];
        return (
            s.streakDays,
            0,
            s.lastStreamDay,
            s.missedDays,
            s.shields,
            s.purchasedShieldsCount,
            s.milestone7Claimed,
            s.milestone30Claimed,
            s.milestone90Claimed,
            s.milestone180Claimed
        );
    }

    function getSystemStatus() external view returns (
        uint256 jackpotBalance,
        uint256 nextJackpotTime,
        uint256 currentWeek,
        bool    isPaused,
        address factory_,
        uint256 shieldCost,
        uint256 maxShields_,
        uint256 legendPoolBps_
    ) {
        return (
            jackpotPool(),
            lastJackpotSettlement + SECONDS_PER_WEEK,
            weekNumber,
            paused,
            address(artistFactory),
            shieldCostMyfi,
            maxShields,
            legendPoolBps
        );
    }

    /**
     * @notice Single call for the jackpot page — all competition data in one read.
     */
    function getJackpotInfo() external view returns (
        uint256 pool,
        uint256 nextDistribution,
        uint256 week,
        uint256 minSize,
        uint256 legendShare,
        uint256 shieldCost_,
        uint256 maxShields_
    ) {
        return (
            jackpotPool(),
            lastJackpotSettlement + SECONDS_PER_WEEK,
            weekNumber,
            minJackpotSize,
            legendPoolBps,
            shieldCostMyfi,
            maxShields
        );
    }

    /**
     * @notice Streak and boosted seconds summary for the profile page.
     */
    function getUserStreakInfo(address user) external view returns (
        uint256 streakDays_,
        uint256 shields_,
        uint256 weeklyBoosted,
        uint256 lifetimeBoosted,
        bool    milestone7,
        bool    milestone30,
        bool    milestone90,
        bool    milestone180
    ) {
        StreakInfo storage s = streaks[user];
        return (
            s.streakDays,
            s.shields,
            weeklyBoostedSeconds[user],
            totalLifetimeBoostedSeconds[user],
            s.milestone7Claimed,
            s.milestone30Claimed,
            s.milestone90Claimed,
            s.milestone180Claimed
        );
    }

    /**
     * @notice Active frame and leaderboard data for the profile page.
     */
    function getUserFrameInfo(address user) external view returns (
        address activeFrameArtist_,
        uint8   activeFrameTier_,
        uint256 weeklyBoosted,
        uint256 lifetimeBoosted
    ) {
        return (
            activeFrameArtist[user],
            activeFrameTier[user],
            weeklyBoostedSeconds[user],
            totalLifetimeBoostedSeconds[user]
        );
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  ADMIN
    // ─────────────────────────────────────────────────────────────────────────

    function setArtistFactory(address _factory) external onlyOwner {
        artistFactory = IArtistTokenFactory(_factory);
    }

    function setKeyStaking(address _ks) external onlyOwner {
        keyStaking = IKEYStaking(_ks);
    }

    function setJackpotToken(address _t)       external onlyOwner { jackpotToken  = _t; }
    function setMinJackpotSize(uint256 _m)     external onlyOwner { minJackpotSize = _m; }
    function setShieldCost(uint256 _costMyfi)  external onlyOwner { shieldCostMyfi = _costMyfi; }
    function setMaxShields(uint256 _max)       external onlyOwner {
        require(_max >= 1 && _max <= 5, "Out of range");
        maxShields = _max;
    }

    function setLegendPoolBps(uint256 _bps) external onlyOwner {
        require(_bps <= 2000, "Max 20%");
        legendPoolBps = _bps;
    }

    function setLegendTierId(uint8 _tierId) external onlyOwner { legendTierId = _tierId; }

    function setDedicatedListenerThresholds(
        uint256 fanSecs,
        uint256 collectorSecs,
        uint256 curatorSecs,
        uint256 legendSecs
    ) external onlyOwner {
        require(
            fanSecs < collectorSecs &&
            collectorSecs < curatorSecs &&
            curatorSecs < legendSecs,
            "Bad order"
        );
        dedicatedFanThreshold       = fanSecs;
        dedicatedCollectorThreshold = collectorSecs;
        dedicatedCuratorThreshold   = curatorSecs;
        dedicatedLegendThreshold    = legendSecs;
    }

    function setSignatureWindow(uint256 _seconds) external onlyOwner {
        require(_seconds >= 60 && _seconds <= 3600, "Bad window");
        signatureWindow = _seconds;
    }

    function setOracleChangeDelay(uint256 _seconds) external onlyOwner {
        require(_seconds >= 3600, "Bad delay");
        oracleChangeDelay = _seconds;
    }

    function setPaused(bool _paused) external onlyOwner { paused = _paused; }

    function proposeOracleSignerChange(address newSigner) external onlyOwner {
        require(newSigner != address(0), "Zero addr");
        pendingOracleSigner    = newSigner;
        oracleSignerChangeTime = block.timestamp + oracleChangeDelay;
        emit OracleSignerProposed(newSigner, oracleSignerChangeTime);
    }

    function executeOracleSignerChange() external onlyOwner {
        require(pendingOracleSigner != address(0),         "No change");
        require(block.timestamp >= oracleSignerChangeTime, "Locked");
        address old         = oracleSigner;
        oracleSigner        = pendingOracleSigner;
        pendingOracleSigner = address(0);
        emit OracleSignerChanged(old, oracleSigner);
    }

    function cancelOracleSignerChange() external onlyOwner {
        pendingOracleSigner = address(0);
    }

    function rescueToken(address token, uint256 amount) external onlyOwner {
        require(token != jackpotToken, "Cannot rescue jackpot token");
        IERC20(token).safeTransfer(owner(), amount);
    }

    // ─────────────────────────────────────────────────────────────────────────
    //  MIGRATION — V5 state import
    // ─────────────────────────────────────────────────────────────────────────

    bool public migrationOpen = true;

    modifier onlyDuringMigration() {
        require(migrationOpen,         "Locked");
        require(msg.sender == owner(), "Auth");
        _;
    }

    function lockMigration() external onlyOwner {
        migrationOpen = false;
        emit MigrationLocked();
    }

    function migrateNonces(
        address[] calldata users,
        uint256[] calldata nonces
    ) external onlyDuringMigration {
        require(users.length == nonces.length, "Mismatch");
        for (uint256 i = 0; i < users.length; i++) {
            if (nonces[i] > userNonces[users[i]])
                userNonces[users[i]] = nonces[i];
        }
    }

    function migrateStreamingHistory(
        address[] calldata users,
        uint256[] calldata lifetimeSecs,
        uint256[] calldata weeklySecs
    ) external onlyDuringMigration {
        require(
            users.length == lifetimeSecs.length &&
            users.length == weeklySecs.length,
            "Mismatch"
        );
        for (uint256 i = 0; i < users.length; i++) {
            totalLifetimeBoostedSeconds[users[i]] += lifetimeSecs[i];
            weeklyBoostedSeconds[users[i]]        += weeklySecs[i];
        }
    }

    function migrateStreaks(
        address[] calldata users,
        StreakInfo[] calldata streakData
    ) external onlyDuringMigration {
        require(users.length == streakData.length, "Mismatch");
        for (uint256 i = 0; i < users.length; i++) {
            streaks[users[i]] = streakData[i];
        }
    }

    function migrateArtistSeconds(
        address[] calldata users,
        address[] calldata artists,
        uint256[] calldata seconds_
    ) external onlyDuringMigration {
        require(
            users.length == artists.length &&
            users.length == seconds_.length,
            "Mismatch"
        );
        for (uint256 i = 0; i < users.length; i++) {
            artistTotalSeconds[users[i]][artists[i]] += seconds_[i];
        }
    }
}
        

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (utils/math/SignedMath.sol)

pragma solidity ^0.8.20;

/**
 * @dev Standard signed math utilities missing in the Solidity language.
 */
library SignedMath {
    /**
     * @dev Returns the largest of two signed numbers.
     */
    function max(int256 a, int256 b) internal pure returns (int256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two signed numbers.
     */
    function min(int256 a, int256 b) internal pure returns (int256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two signed numbers without overflow.
     * The result is rounded towards zero.
     */
    function average(int256 a, int256 b) internal pure returns (int256) {
        // Formula from the book "Hacker's Delight"
        int256 x = (a & b) + ((a ^ b) >> 1);
        return x + (int256(uint256(x) >> 255) & (a ^ b));
    }

    /**
     * @dev Returns the absolute unsigned value of a signed value.
     */
    function abs(int256 n) internal pure returns (uint256) {
        unchecked {
            // must be unchecked in order to support `n = type(int256).min`
            return uint256(n >= 0 ? n : -n);
        }
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (utils/math/Math.sol)

pragma solidity ^0.8.20;

/**
 * @dev Standard math utilities missing in the Solidity language.
 */
library Math {
    /**
     * @dev Muldiv operation overflow.
     */
    error MathOverflowedMulDiv();

    enum Rounding {
        Floor, // Toward negative infinity
        Ceil, // Toward positive infinity
        Trunc, // Toward zero
        Expand // Away from zero
    }

    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @dev Returns the largest of two numbers.
     */
    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    /**
     * @dev Returns the smallest of two numbers.
     */
    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        return a < b ? a : b;
    }

    /**
     * @dev Returns the average of two numbers. The result is rounded towards
     * zero.
     */
    function average(uint256 a, uint256 b) internal pure returns (uint256) {
        // (a + b) / 2 can overflow.
        return (a & b) + (a ^ b) / 2;
    }

    /**
     * @dev Returns the ceiling of the division of two numbers.
     *
     * This differs from standard division with `/` in that it rounds towards infinity instead
     * of rounding towards zero.
     */
    function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        if (b == 0) {
            // Guarantee the same behavior as in a regular Solidity division.
            return a / b;
        }

        // (a + b - 1) / b can overflow on addition, so we distribute.
        return a == 0 ? 0 : (a - 1) / b + 1;
    }

    /**
     * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or
     * denominator == 0.
     * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv) with further edits by
     * Uniswap Labs also under MIT license.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
        unchecked {
            // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
            // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = prod1 * 2^256 + prod0.
            uint256 prod0 = x * y; // Least significant 256 bits of the product
            uint256 prod1; // Most significant 256 bits of the product
            assembly {
                let mm := mulmod(x, y, not(0))
                prod1 := sub(sub(mm, prod0), lt(mm, prod0))
            }

            // Handle non-overflow cases, 256 by 256 division.
            if (prod1 == 0) {
                // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                // The surrounding unchecked block does not change this fact.
                // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                return prod0 / denominator;
            }

            // Make sure the result is less than 2^256. Also prevents denominator == 0.
            if (denominator <= prod1) {
                revert MathOverflowedMulDiv();
            }

            ///////////////////////////////////////////////
            // 512 by 256 division.
            ///////////////////////////////////////////////

            // Make division exact by subtracting the remainder from [prod1 prod0].
            uint256 remainder;
            assembly {
                // Compute remainder using mulmod.
                remainder := mulmod(x, y, denominator)

                // Subtract 256 bit number from 512 bit number.
                prod1 := sub(prod1, gt(remainder, prod0))
                prod0 := sub(prod0, remainder)
            }

            // Factor powers of two out of denominator and compute largest power of two divisor of denominator.
            // Always >= 1. See https://cs.stackexchange.com/q/138556/92363.

            uint256 twos = denominator & (0 - denominator);
            assembly {
                // Divide denominator by twos.
                denominator := div(denominator, twos)

                // Divide [prod1 prod0] by twos.
                prod0 := div(prod0, twos)

                // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                twos := add(div(sub(0, twos), twos), 1)
            }

            // Shift in bits from prod1 into prod0.
            prod0 |= prod1 * twos;

            // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
            // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
            // four bits. That is, denominator * inv = 1 mod 2^4.
            uint256 inverse = (3 * denominator) ^ 2;

            // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also
            // works in modular arithmetic, doubling the correct bits in each step.
            inverse *= 2 - denominator * inverse; // inverse mod 2^8
            inverse *= 2 - denominator * inverse; // inverse mod 2^16
            inverse *= 2 - denominator * inverse; // inverse mod 2^32
            inverse *= 2 - denominator * inverse; // inverse mod 2^64
            inverse *= 2 - denominator * inverse; // inverse mod 2^128
            inverse *= 2 - denominator * inverse; // inverse mod 2^256

            // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
            // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
            // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
            // is no longer required.
            result = prod0 * inverse;
            return result;
        }
    }

    /**
     * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
     */
    function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
        uint256 result = mulDiv(x, y, denominator);
        if (unsignedRoundsUp(rounding) && mulmod(x, y, denominator) > 0) {
            result += 1;
        }
        return result;
    }

    /**
     * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded
     * towards zero.
     *
     * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
     */
    function sqrt(uint256 a) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
        //
        // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
        // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
        //
        // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
        // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
        // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
        //
        // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
        uint256 result = 1 << (log2(a) >> 1);

        // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
        // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
        // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
        // into the expected uint128 result.
        unchecked {
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            result = (result + a / result) >> 1;
            return min(result, a / result);
        }
    }

    /**
     * @notice Calculates sqrt(a), following the selected rounding direction.
     */
    function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = sqrt(a);
            return result + (unsignedRoundsUp(rounding) && result * result < a ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 2 of a positive value rounded towards zero.
     * Returns 0 if given 0.
     */
    function log2(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 128;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 64;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 32;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 16;
            }
            if (value >> 8 > 0) {
                value >>= 8;
                result += 8;
            }
            if (value >> 4 > 0) {
                value >>= 4;
                result += 4;
            }
            if (value >> 2 > 0) {
                value >>= 2;
                result += 2;
            }
            if (value >> 1 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log2(value);
            return result + (unsignedRoundsUp(rounding) && 1 << result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 10 of a positive value rounded towards zero.
     * Returns 0 if given 0.
     */
    function log10(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >= 10 ** 64) {
                value /= 10 ** 64;
                result += 64;
            }
            if (value >= 10 ** 32) {
                value /= 10 ** 32;
                result += 32;
            }
            if (value >= 10 ** 16) {
                value /= 10 ** 16;
                result += 16;
            }
            if (value >= 10 ** 8) {
                value /= 10 ** 8;
                result += 8;
            }
            if (value >= 10 ** 4) {
                value /= 10 ** 4;
                result += 4;
            }
            if (value >= 10 ** 2) {
                value /= 10 ** 2;
                result += 2;
            }
            if (value >= 10 ** 1) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log10(value);
            return result + (unsignedRoundsUp(rounding) && 10 ** result < value ? 1 : 0);
        }
    }

    /**
     * @dev Return the log in base 256 of a positive value rounded towards zero.
     * Returns 0 if given 0.
     *
     * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
     */
    function log256(uint256 value) internal pure returns (uint256) {
        uint256 result = 0;
        unchecked {
            if (value >> 128 > 0) {
                value >>= 128;
                result += 16;
            }
            if (value >> 64 > 0) {
                value >>= 64;
                result += 8;
            }
            if (value >> 32 > 0) {
                value >>= 32;
                result += 4;
            }
            if (value >> 16 > 0) {
                value >>= 16;
                result += 2;
            }
            if (value >> 8 > 0) {
                result += 1;
            }
        }
        return result;
    }

    /**
     * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
     * Returns 0 if given 0.
     */
    function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
        unchecked {
            uint256 result = log256(value);
            return result + (unsignedRoundsUp(rounding) && 1 << (result << 3) < value ? 1 : 0);
        }
    }

    /**
     * @dev Returns whether a provided rounding mode is considered rounding up for unsigned integers.
     */
    function unsignedRoundsUp(Rounding rounding) internal pure returns (bool) {
        return uint8(rounding) % 2 == 1;
    }
}
          

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

pragma solidity ^0.8.20;

import {Math} from "./math/Math.sol";
import {SignedMath} from "./math/SignedMath.sol";

/**
 * @dev String operations.
 */
library Strings {
    bytes16 private constant HEX_DIGITS = "0123456789abcdef";
    uint8 private constant ADDRESS_LENGTH = 20;

    /**
     * @dev The `value` string doesn't fit in the specified `length`.
     */
    error StringsInsufficientHexLength(uint256 value, uint256 length);

    /**
     * @dev Converts a `uint256` to its ASCII `string` decimal representation.
     */
    function toString(uint256 value) internal pure returns (string memory) {
        unchecked {
            uint256 length = Math.log10(value) + 1;
            string memory buffer = new string(length);
            uint256 ptr;
            /// @solidity memory-safe-assembly
            assembly {
                ptr := add(buffer, add(32, length))
            }
            while (true) {
                ptr--;
                /// @solidity memory-safe-assembly
                assembly {
                    mstore8(ptr, byte(mod(value, 10), HEX_DIGITS))
                }
                value /= 10;
                if (value == 0) break;
            }
            return buffer;
        }
    }

    /**
     * @dev Converts a `int256` to its ASCII `string` decimal representation.
     */
    function toStringSigned(int256 value) internal pure returns (string memory) {
        return string.concat(value < 0 ? "-" : "", toString(SignedMath.abs(value)));
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        unchecked {
            return toHexString(value, Math.log256(value) + 1);
        }
    }

    /**
     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        uint256 localValue = value;
        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_DIGITS[localValue & 0xf];
            localValue >>= 4;
        }
        if (localValue != 0) {
            revert StringsInsufficientHexLength(value, length);
        }
        return string(buffer);
    }

    /**
     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal
     * representation.
     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), ADDRESS_LENGTH);
    }

    /**
     * @dev Returns true if the two strings are equal.
     */
    function equal(string memory a, string memory b) internal pure returns (bool) {
        return bytes(a).length == bytes(b).length && keccak256(bytes(a)) == keccak256(bytes(b));
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (utils/cryptography/MessageHashUtils.sol)

pragma solidity ^0.8.20;

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

/**
 * @dev Signature message hash utilities for producing digests to be consumed by {ECDSA} recovery or signing.
 *
 * The library provides methods for generating a hash of a message that conforms to the
 * https://eips.ethereum.org/EIPS/eip-191[EIP 191] and https://eips.ethereum.org/EIPS/eip-712[EIP 712]
 * specifications.
 */
library MessageHashUtils {
    /**
     * @dev Returns the keccak256 digest of an EIP-191 signed data with version
     * `0x45` (`personal_sign` messages).
     *
     * The digest is calculated by prefixing a bytes32 `messageHash` with
     * `"\x19Ethereum Signed Message:\n32"` and hashing the result. It corresponds with the
     * hash signed when using the https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`] JSON-RPC method.
     *
     * NOTE: The `messageHash` parameter is intended to be the result of hashing a raw message with
     * keccak256, although any bytes32 value can be safely used because the final digest will
     * be re-hashed.
     *
     * See {ECDSA-recover}.
     */
    function toEthSignedMessageHash(bytes32 messageHash) internal pure returns (bytes32 digest) {
        /// @solidity memory-safe-assembly
        assembly {
            mstore(0x00, "\x19Ethereum Signed Message:\n32") // 32 is the bytes-length of messageHash
            mstore(0x1c, messageHash) // 0x1c (28) is the length of the prefix
            digest := keccak256(0x00, 0x3c) // 0x3c is the length of the prefix (0x1c) + messageHash (0x20)
        }
    }

    /**
     * @dev Returns the keccak256 digest of an EIP-191 signed data with version
     * `0x45` (`personal_sign` messages).
     *
     * The digest is calculated by prefixing an arbitrary `message` with
     * `"\x19Ethereum Signed Message:\n" + len(message)` and hashing the result. It corresponds with the
     * hash signed when using the https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`] JSON-RPC method.
     *
     * See {ECDSA-recover}.
     */
    function toEthSignedMessageHash(bytes memory message) internal pure returns (bytes32) {
        return
            keccak256(bytes.concat("\x19Ethereum Signed Message:\n", bytes(Strings.toString(message.length)), message));
    }

    /**
     * @dev Returns the keccak256 digest of an EIP-191 signed data with version
     * `0x00` (data with intended validator).
     *
     * The digest is calculated by prefixing an arbitrary `data` with `"\x19\x00"` and the intended
     * `validator` address. Then hashing the result.
     *
     * See {ECDSA-recover}.
     */
    function toDataWithIntendedValidatorHash(address validator, bytes memory data) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked(hex"19_00", validator, data));
    }

    /**
     * @dev Returns the keccak256 digest of an EIP-712 typed data (EIP-191 version `0x01`).
     *
     * The digest is calculated from a `domainSeparator` and a `structHash`, by prefixing them with
     * `\x19\x01` and hashing the result. It corresponds to the hash signed by the
     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] JSON-RPC method as part of EIP-712.
     *
     * See {ECDSA-recover}.
     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 digest) {
        /// @solidity memory-safe-assembly
        assembly {
            let ptr := mload(0x40)
            mstore(ptr, hex"19_01")
            mstore(add(ptr, 0x02), domainSeparator)
            mstore(add(ptr, 0x22), structHash)
            digest := keccak256(ptr, 0x42)
        }
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.20;

/**
 * @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
    }

    /**
     * @dev The signature derives the `address(0)`.
     */
    error ECDSAInvalidSignature();

    /**
     * @dev The signature has an invalid length.
     */
    error ECDSAInvalidSignatureLength(uint256 length);

    /**
     * @dev The signature has an S value that is in the upper half order.
     */
    error ECDSAInvalidSignatureS(bytes32 s);

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with `signature` or an error. This will not
     * return address(0) without also returning an error description. Errors are documented using an enum (error type)
     * and a bytes32 providing additional information about the error.
     *
     * If no error is returned, then the address can be used for verification purposes.
     *
     * The `ecrecover` EVM precompile 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 {MessageHashUtils-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]
     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError, bytes32) {
        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.
            /// @solidity memory-safe-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 {
            return (address(0), RecoverError.InvalidSignatureLength, bytes32(signature.length));
        }
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM precompile 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 {MessageHashUtils-toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error, bytes32 errorArg) = tryRecover(hash, signature);
        _throwError(error, errorArg);
        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]
     */
    function tryRecover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address, RecoverError, bytes32) {
        unchecked {
            bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
            // We do not check for an overflow here since the shift operation results in 0 or 1.
            uint8 v = uint8((uint256(vs) >> 255) + 27);
            return tryRecover(hash, v, r, s);
        }
    }

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

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

        // 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, bytes32(0));
        }

        return (signer, RecoverError.NoError, bytes32(0));
    }

    /**
     * @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, bytes32 errorArg) = tryRecover(hash, v, r, s);
        _throwError(error, errorArg);
        return recovered;
    }

    /**
     * @dev Optionally reverts with the corresponding custom error according to the `error` argument provided.
     */
    function _throwError(RecoverError error, bytes32 errorArg) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert ECDSAInvalidSignature();
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert ECDSAInvalidSignatureLength(uint256(errorArg));
        } else if (error == RecoverError.InvalidSignatureS) {
            revert ECDSAInvalidSignatureS(errorArg);
        }
    }
}
          

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

pragma solidity ^0.8.20;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev The ETH balance of the account is not enough to perform the operation.
     */
    error AddressInsufficientBalance(address account);

    /**
     * @dev There's no code at `target` (it is not a contract).
     */
    error AddressEmptyCode(address target);

    /**
     * @dev A call to an address target failed. The target may have reverted.
     */
    error FailedInnerCall();

    /**
     * @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://consensys.net/diligence/blog/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/v0.8.20/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        if (address(this).balance < amount) {
            revert AddressInsufficientBalance(address(this));
        }

        (bool success, ) = recipient.call{value: amount}("");
        if (!success) {
            revert FailedInnerCall();
        }
    }

    /**
     * @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 or custom error, it is bubbled
     * up by this function (like regular Solidity function calls). However, if
     * the call reverted with no returned reason, this function reverts with a
     * {FailedInnerCall} error.
     *
     * 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.
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0);
    }

    /**
     * @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`.
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        if (address(this).balance < value) {
            revert AddressInsufficientBalance(address(this));
        }
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and reverts if the target
     * was not a contract or bubbling up the revert reason (falling back to {FailedInnerCall}) in case of an
     * unsuccessful call.
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata
    ) internal view returns (bytes memory) {
        if (!success) {
            _revert(returndata);
        } else {
            // only check if target is a contract if the call was successful and the return data is empty
            // otherwise we already know that it was a contract
            if (returndata.length == 0 && target.code.length == 0) {
                revert AddressEmptyCode(target);
            }
            return returndata;
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and reverts if it wasn't, either by bubbling the
     * revert reason or with a default {FailedInnerCall} error.
     */
    function verifyCallResult(bool success, bytes memory returndata) internal pure returns (bytes memory) {
        if (!success) {
            _revert(returndata);
        } else {
            return returndata;
        }
    }

    /**
     * @dev Reverts with returndata if present. Otherwise reverts with {FailedInnerCall}.
     */
    function _revert(bytes memory returndata) private pure {
        // 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
            /// @solidity memory-safe-assembly
            assembly {
                let returndata_size := mload(returndata)
                revert(add(32, returndata), returndata_size)
            }
        } else {
            revert FailedInnerCall();
        }
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 *
 * ==== Security Considerations
 *
 * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
 * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
 * considered as an intention to spend the allowance in any specific way. The second is that because permits have
 * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
 * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
 * generally recommended is:
 *
 * ```solidity
 * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
 *     try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
 *     doThing(..., value);
 * }
 *
 * function doThing(..., uint256 value) public {
 *     token.safeTransferFrom(msg.sender, address(this), value);
 *     ...
 * }
 * ```
 *
 * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
 * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
 * {SafeERC20-safeTransferFrom}).
 *
 * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
 * contracts should have entry points that don't rely on permit.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     *
     * CAUTION: See Security Considerations above.
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.20;

import {IERC20} from "../IERC20.sol";
import {IERC20Permit} from "../extensions/IERC20Permit.sol";
import {Address} from "../../../utils/Address.sol";

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

    /**
     * @dev An operation with an ERC20 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 {
        _callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value)));
    }

    /**
     * @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 {
        _callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value)));
    }

    /**
     * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
     * non-reverting calls are assumed to be successful.
     */
    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.
     */
    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.
     */
    function forceApprove(IERC20 token, address spender, uint256 value) internal {
        bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value));

        if (!_callOptionalReturnBool(token, approvalCall)) {
            _callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0)));
            _callOptionalReturn(token, approvalCall);
        }
    }

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

        bytes memory returndata = address(token).functionCall(data);
        if (returndata.length != 0 && !abi.decode(returndata, (bool))) {
            revert SafeERC20FailedOperation(address(token));
        }
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     *
     * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
        // and not revert is the subcall reverts.

        (bool success, bytes memory returndata) = address(token).call(data);
        return success && (returndata.length == 0 || abi.decode(returndata, (bool))) && address(token).code.length > 0;
    }
}
          

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
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 v5.0.0) (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);
    }
}
          

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

pragma solidity ^0.8.20;

/**
 * @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;

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

    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() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be NOT_ENTERED
        if (_status == ENTERED) {
            revert ReentrancyGuardReentrantCall();
        }

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

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