Forkchoice Ethereum Mainnet

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.30;

/*──────────────────────────────────────────────────────────────────────────────
 * DSF White-Label Vault (WL) — accounting of the deposit principal in USDT (settleIndex)
 *
 * Public methods are identical to DSF by signatures:
 *   - deposit(uint256[POOL_ASSETS] memory amounts)
 *   - withdraw(uint256 lpShares, uint256[POOL_ASSETS] memory tokenAmounts,
 *              IStrategy.WithdrawalType withdrawalType, uint128 tokenIndex)
 *
 * Calculation order:
 *   1) totalGrossSettle       = previewTotalGrossPerToken()[settleIndex] for the entire WL
 *   2) pendingVaultFeeSettle  = uncrystallized HWM fee of the WL
 *   3) totalHoldingsSettle    = totalGrossSettle - pendingVaultFeeSettle
 *   4) LPprice                = totalHoldingsSettle / totalSupply
 *   5) userNet                = wlShares * LPprice
 *
 * Principal accounting (in USDT):
 *   - Deposit:    userPrincipalSettle += availableToWithdrawal(wlMint)
 *   - Withdrawal: we compute availableToWithdrawal(wlShares),
 *                 split it into principal / profit, decrease userPrincipalSettle
 *                 only by the “principal” part.
 *   - Transfer:   proportionally move part of userPrincipalSettle from → to.
 *
 * User transaction history (always in the settle token, e.g. USDT):
 *   kind:
 *     0 = deposit      (amountSettle = NET deposit in settle)
 *     1 = withdrawal   (amountSettle = NET withdrawal in settle)
 *     2 = OUT transfer (from → to, amountSettle = NET settle-value of WL shares sent from `from`)
 *     3 = IN transfer  (to ← from, amountSettle = NET settle-value of WL shares received by `to`)
 *
 * Future income (CRV + CVX and others):
 *   - External contract futureIncomeSource provides futureIncome() — GROSS income
 *     for ALL DSF LP (for dsfLp.totalSupply()), in the settle token.
 *   - WL share (GROSS): futureGrossWL = futureTotal * dsfLpBalance(WL) / dsfLpTotalSupply
 *   - WL users’ share (NET of WL fee):
 *         totalFutureIncomeUsers = futureGrossWL * (DENOM - partnerFeeBps) / DENOM
 *   - User share:
 *         userFuture = totalFutureIncomeUsers * wlUser / totalSupply
 *
 * IMPORTANT: Slippage protection is fully implemented in the main DSF contracts.
 * WL only forwards parameters.
 *──────────────────────────────────────────────────────────────────────────────*/

import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {Pausable} from "@openzeppelin/contracts/security/Pausable.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";

/* ── Mini-interfaces to the already deployed DSF ───────────────────────────── */

interface IDSF {
    enum WithdrawalType { Base, OneCoin }

    function deposit(uint256[3] calldata amounts) external returns (uint256 lpMinted);

    function withdraw(
        uint256 lpShares,
        uint256[3] calldata minOut,
        WithdrawalType wType,
        uint128 tokenIndex
    ) external;

    function defaultWithdrawPid() external view returns (uint256);
    function poolInfo(uint256 pid)
        external
        view
        returns (address strategy, uint256 startTime, uint256 lpShares);
}

// Only to keep enum in the signature identical to DSF
interface IStrategy {
    enum WithdrawalType { Base, OneCoin }
}

// DSF Strategy: one-coin preview by LP share (1e18)
interface IStrategyView {
    function calcWithdrawOneCoin(uint256 lpShareRatio1e18, uint128 tokenIndex)
        external
        view
        returns (uint256 tokenAmount);
}

/**
 * @dev External contract that provides total future income for DSF LP (CRV+CVX etc.)
 *      in the settle token (USDT).
 *
 * Semantics:
 *  - futureIncome() = future income for the entire dsfLp.totalSupply() (GROSS).
 */
interface IFutureIncome {
    function futureIncome() external view returns (uint256);
}

contract DsfWhiteLabelVault_USDT is ERC20, Ownable, Pausable, ReentrancyGuard {
    using SafeERC20 for IERC20;

    // ───────── Constants / parameters
    uint8   public constant POOL_ASSETS = 3;
    uint256 public constant DENOM       = 10_000;   // bps
    uint256 public constant USER_COOLDOWN_BLOCKS = 1;

    /// @notice Threshold for HWM-skim, GROSS WL price growth in bps
    uint256 public minSkimGainBps = 1; // 0.01%

    // ───────── External addresses
    IDSF   public immutable dsf;
    IERC20 public immutable dsfLp;
    IERC20[POOL_ASSETS] public tokens;     // [DAI, USDC, USDT]

    /// @notice Index of the settle token (0..2) — by default USDT
    uint128 public settleIndex = 2;

    /// @notice Treasury of the WL owner (receives fee in DSF LP)
    address public principalTreasury;

    /// @notice WL owner fee (HWM fee), in bps (e.g., 3000 = 30%)
    uint16 public partnerFeeBps;

    /// @notice External source of future income (in the settle token)
    IFutureIncome public futureIncomeSource;

    // ───────── Accounting / anti-MEV
    uint256 public HWM_settlePerWL;          // high-water mark (GROSS settle per WL)
    uint256 public lastNavTouchBlock;        // NAV protection within a single block
    mapping(address => uint256) public lastUserActionBlock; // per-user cooldown

    /// @notice Total crystallized fee (in settle token equivalent) — analytics only
    uint256 public ownerCrystallizedSettle;

    /// @notice User deposit principal (“body”) in the settle token (NET)
    mapping(address => uint256) public userPrincipalSettle;

    // ───────── User operation history (always in the settle token)
    struct TxRecord {
        uint8   kind;         // 0=deposit, 1=withdraw, 2=transferOut, 3=transferIn
        uint64  timestamp;    // block.timestamp
        uint256 amountSettle; // amount in settle token (USDT equivalent), NET at operation time
    }

    mapping(address => TxRecord[]) private _userTxHistory;

    // ───────── Events
    event DepositWL(address indexed user, uint256[3] amounts, uint256 wlMinted, uint256 dsfLpGained);
    event WithdrawWL(address indexed user, uint256 wlBurned, uint256 dsfLpSpent, uint256[3] paidToUser);

    event SkimPrincipal(uint256 feeSettle, uint256 dsfLpFeeToPrincipal, uint256 newHwmPriceSettlePerWL);

    event UpdatePartnerFeeBps(uint16 newBps);
    event UpdatePrincipalTreasury(address newTreasury);
    event UpdateMinSkimGainBps(uint256 newMinBps);
    event UpdateSettleIndex(uint128 newIndex);
    event UpdateFutureIncomeSource(address newSource);

    event PrincipalSettleIncreased(address indexed user, uint256 addedSettle, uint256 newPrincipalSettle);
    event WithdrawBreakdownSettle(
        address indexed user,
        uint256 wlBurned,
        uint256 previewSettleOutNet,
        uint256 principalSettlePortion,
        uint256 profitSettlePortion
    );

    constructor(
        address _dsf,
        address _dsfLp,
        address[POOL_ASSETS] memory _tokens,
        address _principalTreasury,
        uint16  _partnerFeeBps,
        uint128 _settleIndex,
        address _futureIncomeSource   // can be address(0) if not configured yet
    )
        Ownable(msg.sender)
        ERC20("DSF WL Shares", "DSFWL")
    {
        require(_dsf != address(0) && _dsfLp != address(0), "WL: bad DSF addrs");
        require(_principalTreasury != address(0), "WL: bad treasury");
        require(_partnerFeeBps <= DENOM, "WL: fee too high");
        require(_settleIndex < POOL_ASSETS, "WL: bad settle index");

        dsf = IDSF(_dsf);
        dsfLp = IERC20(_dsfLp);
        principalTreasury = _principalTreasury;
        partnerFeeBps = _partnerFeeBps;
        settleIndex = _settleIndex;

        for (uint i = 0; i < POOL_ASSETS; i++) {
            require(_tokens[i] != address(0), "WL: bad token");
            tokens[i] = IERC20(_tokens[i]);
        }

        if (_futureIncomeSource != address(0)) {
            futureIncomeSource = IFutureIncome(_futureIncomeSource);
        }

        HWM_settlePerWL = 0; // will be set on first deposit
    }

    // ───────── Admin settings

    function setPartnerFeeBps(uint16 bps) external onlyOwner {
        require(bps <= DENOM, "WL: fee too high");
        partnerFeeBps = bps;
        emit UpdatePartnerFeeBps(bps);
    }

    function setPrincipalTreasury(address t) external onlyOwner {
        require(t != address(0), "WL: bad treasury");
        principalTreasury = t;
        emit UpdatePrincipalTreasury(t);
    }

    function setMinSkimGainBps(uint256 bps) external onlyOwner {
        minSkimGainBps = bps;
        emit UpdateMinSkimGainBps(bps);
    }

    /// Recommendation: change settleIndex only when WL is empty (require can be uncommented)
    function setSettleIndex(uint128 idx) external onlyOwner {
        require(idx < POOL_ASSETS, "WL: bad settle index");
        // require(totalSupply() == 0, "WL: change settleIndex only when empty");
        settleIndex = idx;
        emit UpdateSettleIndex(idx);
    }

    /// @notice Set external source of future income (DSF / strategy / analytics)
    function setFutureIncomeSource(address src) external onlyOwner {
        // address(0) — disable future income accounting
        futureIncomeSource = IFutureIncome(src);
        emit UpdateFutureIncomeSource(src);
    }

    function pause() external onlyOwner { _pause(); }
    function unpause() external onlyOwner { _unpause(); }

    // ───────── Internal utilities / cooldown

    function _touchNav() internal {
        lastNavTouchBlock = block.number;
    }

    modifier userCooldown() {
        require(block.number > lastUserActionBlock[msg.sender] + USER_COOLDOWN_BLOCKS, "WL: cooldown");
        _;
        lastUserActionBlock[msg.sender] = block.number;
    }

    function _amountsMask(
        uint256[POOL_ASSETS] memory amounts,
        IStrategy.WithdrawalType wType,
        uint128 tokenIdx
    ) internal pure returns (uint256[POOL_ASSETS] memory out) {
        if (wType == IStrategy.WithdrawalType.OneCoin) {
            for (uint i = 0; i < POOL_ASSETS; i++) out[i] = 0;
            out[uint256(tokenIdx)] = amounts[uint256(tokenIdx)];
        } else {
            return amounts;
        }
    }

    // ───────── NAV / GROSS / NET (preview through DSF strategy)

    /// @dev GROSS preview: how much of each token [0..2] WL would receive
    ///      if it withdrew ALL dsfLp as one-coin via defaultWithdrawPid.
    function _previewTotalGrossPerToken()
        internal
        view
        returns (uint256[POOL_ASSETS] memory grossAll)
    {
        uint256 lpBalance = dsfLp.balanceOf(address(this));
        if (lpBalance == 0) return grossAll;

        uint256 pid = dsf.defaultWithdrawPid();
        (address strat,, uint256 poolLpShares) = dsf.poolInfo(pid);
        if (poolLpShares == 0) return grossAll;

        uint256 ratio1e18 = (lpBalance * 1e18) / poolLpShares;
        if (ratio1e18 == 0) return grossAll;
        if (ratio1e18 > 1e18) ratio1e18 = 1e18;

        for (uint i = 0; i < POOL_ASSETS; i++) {
            grossAll[i] = IStrategyView(strat).calcWithdrawOneCoin(ratio1e18, uint128(i));
        }
    }

    /// @dev GROSS NAV of WL in the settle token (before WL fee)
    function totalGrossSettle() public view returns (uint256) {
        uint256[POOL_ASSETS] memory grossAll = _previewTotalGrossPerToken();
        return grossAll[settleIndex];
    }

    /// @dev GROSS price of 1 WL share in the settle token
    function wlPriceGrossSettle() public view returns (uint256) {
        uint256 ts = totalSupply();
        if (ts == 0) return 0;
        uint256 g = totalGrossSettle();
        return g / ts;
    }

    /// @dev Uncrystallized WL HWM fee (in the settle token)
    function pendingVaultFeeSettle() public view returns (uint256) {
        uint256 ts = totalSupply();
        if (ts == 0 || HWM_settlePerWL == 0) return 0;

        uint256 priceGross = wlPriceGrossSettle();
        if (priceGross <= HWM_settlePerWL) return 0;

        uint256 profit = (priceGross - HWM_settlePerWL) * ts;
        return (profit * partnerFeeBps) / DENOM;
    }

    /// @notice NET total holdings of all WL users in the settle token
    function totalHoldingsSettle() public view returns (uint256) {
        uint256 g = totalGrossSettle();
        uint256 f = pendingVaultFeeSettle();
        return g > f ? g - f : 0;
    }

    /// @notice NET price of 1 WL share (LPprice) in the settle token, 1e18 precision
    function LPprice() public view returns (uint256) {
        uint256 ts = totalSupply();
        if (ts == 0) return 0;
        return (totalHoldingsSettle() * 1e18) / ts;
    }

    /// @notice NET value of `wlShares` in the settle token (what can be withdrawn now)
    function availableToWithdrawal(uint256 wlShares) public view returns (uint256) {
        uint256 px = LPprice();
        return (wlShares * px) / 1e18;
    }

    /// @notice NET value of `wlShares` expressed in each of the three tokens (DAI/USDC/USDT)
    function availableToWithdrawalPerToken(uint256 wlShares)
        public
        view
        returns (uint256[POOL_ASSETS] memory out)
    {
        if (wlShares == 0) return out;

        uint256[POOL_ASSETS] memory grossAll = _previewTotalGrossPerToken();
        uint256 ts = totalSupply();
        if (ts == 0) return out;

        uint256 grossSettle = grossAll[settleIndex];
        uint256 feeSettle   = pendingVaultFeeSettle();

        if (grossSettle == 0) return out;

        uint256 netSettleAll_ = grossSettle > feeSettle ? grossSettle - feeSettle : 0;
        if (netSettleAll_ == 0) return out;

        // netFactor ~= NET/GROSS in settle; apply it as a factor to all tokens
        for (uint i = 0; i < POOL_ASSETS; i++) {
            uint256 netAllToken = (grossAll[i] * netSettleAll_) / grossSettle;
            out[i] = (wlShares * netAllToken) / ts;
        }
    }

    // ───────── User views (current NAV / PnL)

    function userAvailableNow(address user) external view returns (uint256) {
        return availableToWithdrawal(balanceOf(user));
    }

    /// @notice Current NET user value per three tokens (DAI/USDC/USDT)
    function userAvailableNowPerToken(address user)
        external
        view
        returns (uint256[POOL_ASSETS] memory)
    {
        return availableToWithdrawalPerToken(balanceOf(user));
    }

    /// @notice Current user deposit principal in the settle token
    function userDepositeNow(address user) external view returns (uint256) {
        return userPrincipalSettle[user];
    }

    /// @notice Current NET profit of the user in the settle token (NAV - principal)
    function userNetProfit(address user) external view returns (uint256) {
        uint256 bal = balanceOf(user);
        if (bal == 0) return 0;
        uint256 totalSettle = availableToWithdrawal(bal);
        uint256 principal   = userPrincipalSettle[user];
        return totalSettle > principal ? totalSettle - principal : 0;
    }

    // ───────── Future income (CRV+CVX+...), NET user income only

    /// @dev Internal GROSS future income of WL (before WL fee), in the settle token
    function _totalFutureIncomeGross() internal view returns (uint256) {
        IFutureIncome src = futureIncomeSource;
        if (address(src) == address(0)) return 0;

        uint256 futureTotal = src.futureIncome(); // income for the entire dsfLp.totalSupply()
        if (futureTotal == 0) return 0;

        uint256 lpBalance     = dsfLp.balanceOf(address(this));
        uint256 lpTotalSupply = dsfLp.totalSupply();
        if (lpBalance == 0 || lpTotalSupply == 0) return 0;

        // GROSS WL share in the total future DSF LP income
        return (futureTotal * lpBalance) / lpTotalSupply;
    }

    /// @notice NET future income of WL users (after WL fee), in the settle token
    function totalFutureIncomeUsers() public view returns (uint256) {
        uint256 gross = _totalFutureIncomeGross();
        if (gross == 0) return 0;
        // Users’ net share: (DENOM - partnerFeeBps) / DENOM
        return (gross * (DENOM - partnerFeeBps)) / DENOM;
    }

    /// @notice Split of future income: users’ share and WL owner’s share (estimated)
    function futureIncomeSplit()
        external
        view
        returns (uint256 usersFutureSettle, uint256 ownerFutureSettle)
    {
        uint256 gross = _totalFutureIncomeGross();
        if (gross == 0) return (0, 0);

        ownerFutureSettle = (gross * partnerFeeBps) / DENOM;
        usersFutureSettle = gross - ownerFutureSettle;
    }

    /// @notice NET future income per 1 WL share, 1e18 precision
    function futureIncomePerShare1e18() public view returns (uint256) {
        uint256 ts = totalSupply();
        if (ts == 0) return 0;
        return (totalFutureIncomeUsers() * 1e18) / ts;
    }

    /// @notice Future income of a specific user (NET, after WL fee), in the settle token
    function userFutureIncome(address user) public view returns (uint256) {
        uint256 wl = balanceOf(user);
        if (wl == 0) return 0;
        uint256 px = futureIncomePerShare1e18();
        return (wl * px) / 1e18;
    }

    /// @notice totalWithFuture: current NET + future income for the user (all in settle token)
    function userTotalWithFuture(address user)
        external
        view
        returns (uint256 currentNet, uint256 futureNet, uint256 total)
    {
        uint256 wl = balanceOf(user);
        if (wl == 0) return (0, 0, 0);

        currentNet = availableToWithdrawal(wl);
        futureNet  = userFutureIncome(user);
        total      = currentNet + futureNet;
    }

    // ───────── User history

    function getUserTxCount(address user) external view returns (uint256) {
        return _userTxHistory[user].length;
    }

    function getUserTx(address user, uint256 index)
        external
        view
        returns (uint8 kind, uint64 timestamp, uint256 amountSettle)
    {
        TxRecord storage r = _userTxHistory[user][index];
        return (r.kind, r.timestamp, r.amountSettle);
    }

    /// Return the entire history (for off-chain reading)
    function getUserTxHistory(address user) external view returns (TxRecord[] memory history) {
        uint256 len = _userTxHistory[user].length;
        history = new TxRecord[](len);
        for (uint256 i = 0; i < len; i++) {
            history[i] = _userTxHistory[user][i];
        }
    }

    // ───────── soft auto-skim (crystallization of HWM fee in DSF LP)

    function _trySkim() internal {
        if (block.number <= lastNavTouchBlock) return;

        uint256 ts = totalSupply();
        if (ts == 0) { HWM_settlePerWL = 0; return; }

        uint256 priceGross = wlPriceGrossSettle();
        if (HWM_settlePerWL == 0) { HWM_settlePerWL = priceGross; return; }

        if (priceGross * DENOM < HWM_settlePerWL * (DENOM + minSkimGainBps)) return;

        uint256 feeSettle = pendingVaultFeeSettle();
        if (feeSettle == 0) { HWM_settlePerWL = priceGross; return; }

        uint256 lpBalance   = dsfLp.balanceOf(address(this));
        uint256 grossSettle = totalGrossSettle();
        if (grossSettle == 0 || lpBalance == 0) { HWM_settlePerWL = priceGross; return; }

        // feeLp = feeSettle * lpBalance / grossSettle
        uint256 feeLp = (feeSettle * lpBalance) / grossSettle;
        uint256 balLp = dsfLp.balanceOf(address(this));
        if (feeLp > balLp) feeLp = balLp;

        if (feeLp > 0) {
            dsfLp.safeTransfer(principalTreasury, feeLp);
            ownerCrystallizedSettle += feeSettle;
            _touchNav();
        }

        HWM_settlePerWL = priceGross;
        emit SkimPrincipal(feeSettle, feeLp, priceGross);
    }

    // ───────── DEPOSIT (signature identical to DSF)

    function deposit(uint256[POOL_ASSETS] memory amounts)
        external
        nonReentrant
        whenNotPaused
        userCooldown
    {
        _trySkim(); 

        // 1) Pull tokens from the user
        for (uint i = 0; i < POOL_ASSETS; i++) {
            if (amounts[i] > 0) {
                tokens[i].safeTransferFrom(msg.sender, address(this), amounts[i]);
            }
        }
        // 2) Approve DSF and call deposit
        for (uint i = 0; i < POOL_ASSETS; i++) {
            if (amounts[i] > 0) {
                tokens[i].forceApprove(address(dsf), 0);
                tokens[i].forceApprove(address(dsf), amounts[i]);
            }
        }

        uint256 lpBefore = dsfLp.balanceOf(address(this));
        dsf.deposit(amounts); // slippage checks are inside DSF
        uint256 lpAfter  = dsfLp.balanceOf(address(this));
        uint256 lpGained = lpAfter - lpBefore;
        require(lpGained > 0, "WL: no dsf lp");

        // 3) Mint WL shares proportionally to DSF LP
        uint256 tsBefore = totalSupply();
        uint256 wlMint;
        if (tsBefore == 0) {
            wlMint = lpGained; // start 1:1 WL↔LP
        } else {
            wlMint = (tsBefore * lpGained) / lpBefore;
        }
        _mint(msg.sender, wlMint);

        // 4) Fix deposit principal in the settle token at CURRENT NET price
        uint256 addedPrincipalSettle = availableToWithdrawal(wlMint);
        if (addedPrincipalSettle > 0) {
            userPrincipalSettle[msg.sender] += addedPrincipalSettle;
            emit PrincipalSettleIncreased(msg.sender, addedPrincipalSettle, userPrincipalSettle[msg.sender]);

            // History: deposit (kind = 0), amountSettle = NET deposit in settle
            _userTxHistory[msg.sender].push(
                TxRecord({
                    kind: 0,
                    timestamp: uint64(block.timestamp),
                    amountSettle: addedPrincipalSettle
                })
            );
        }

        // 5) If this is the first deposit — set HWM by GROSS price
        if (tsBefore == 0) {
            HWM_settlePerWL = wlPriceGrossSettle();
        }

        _touchNav();
        emit DepositWL(msg.sender, amounts, wlMint, lpGained);
    }

    // ───────── WITHDRAW (signature identical to DSF)

    /// @param lpShares Amount of WL shares to burn (name kept for DSF compatibility)
    /// @param tokenAmounts In DSF this is minOut per token — forwarded as is
    /// @param withdrawalType DSF mode: Base/OneCoin — forwarded as is
    /// @param tokenIndex Index for OneCoin — forwarded as is (0..2)
    function withdraw(
        uint256 lpShares,
        uint256[POOL_ASSETS] memory tokenAmounts,
        IStrategy.WithdrawalType withdrawalType,
        uint128 tokenIndex
    )
        external
        nonReentrant
        whenNotPaused
        userCooldown
    {
        require(
            withdrawalType == IStrategy.WithdrawalType.OneCoin,
            "WL: only one-coin"
        );
        _trySkim();

        require(lpShares > 0 && balanceOf(msg.sender) >= lpShares, "WL: bad shares");

        // NET preview in the settle token for these WL shares
        uint256 previewSettleOutNet = availableToWithdrawal(lpShares);

        // Split into principal/profit in the user’s accounting
        uint256 principalSettlePortion =
            previewSettleOutNet <= userPrincipalSettle[msg.sender]
                ? previewSettleOutNet
                : userPrincipalSettle[msg.sender];
        uint256 profitSettlePortion = previewSettleOutNet - principalSettlePortion;

        if (principalSettlePortion > 0) {
            userPrincipalSettle[msg.sender] -= principalSettlePortion;
        }

        uint256 tsBefore    = totalSupply();
        uint256 lpBalBefore = dsfLp.balanceOf(address(this));
        require(tsBefore > 0 && lpBalBefore > 0, "WL: empty");

        // Proportional WL → DSF LP conversion
        uint256 dsfLpRedeem = (lpBalBefore * lpShares) / tsBefore;
        require(dsfLpRedeem > 0, "WL: zero redeem");

        _burn(msg.sender, lpShares);

        uint256[POOL_ASSETS] memory balBefore;
        for (uint i = 0; i < POOL_ASSETS; i++) {
            balBefore[i] = IERC20(tokens[i]).balanceOf(address(this));
        }

        dsfLp.forceApprove(address(dsf), 0);
        dsfLp.forceApprove(address(dsf), dsfLpRedeem);

        // All slippage and minOut conditions are inside DSF
        dsf.withdraw(
            dsfLpRedeem,
            _amountsMask(tokenAmounts, withdrawalType, tokenIndex),
            withdrawalType == IStrategy.WithdrawalType.Base ? IDSF.WithdrawalType.Base : IDSF.WithdrawalType.OneCoin,
            tokenIndex
        );

        uint256[POOL_ASSETS] memory got;
        for (uint i = 0; i < POOL_ASSETS; i++) {
            uint256 balAfter = IERC20(tokens[i]).balanceOf(address(this));
            uint256 delta = balAfter - balBefore[i];
            got[i] = delta;
            if (delta > 0) tokens[i].safeTransfer(msg.sender, delta);
        }

        _touchNav();

        // History: withdraw (kind = 1), log NET in settle token
        _userTxHistory[msg.sender].push(
            TxRecord({
                kind: 1,
                timestamp: uint64(block.timestamp),
                amountSettle: previewSettleOutNet
            })
        );

        emit WithdrawWL(msg.sender, lpShares, dsfLpRedeem, got);
        emit WithdrawBreakdownSettle(
            msg.sender,
            lpShares,
            previewSettleOutNet,
            principalSettlePortion,
            profitSettlePortion
        );
    }

    // ───────── Override transfer logic to account principal and history
    /// ERC20 v5: _update is called on mint/burn/transfer
    function _update(address from, address to, uint256 value) internal override {
        // Mint
        if (from == address(0)) {
            super._update(from, to, value);
            return;
        }

        // Burn
        if (to == address(0)) {
            super._update(from, to, value);
            return;
        }

        // Regular transfer: move proportional principal + log history in settle token
        if (value > 0) {
            uint256 fromBalanceBefore = balanceOf(from);
            uint256 fromPrincipal     = userPrincipalSettle[from];

            // Proportional principal transfer from `from` → `to`
            if (fromBalanceBefore > 0 && fromPrincipal > 0) {
                uint256 movedPrincipal = (fromPrincipal * value) / fromBalanceBefore;
                if (movedPrincipal > 0) {
                    userPrincipalSettle[from] = fromPrincipal - movedPrincipal;
                    userPrincipalSettle[to]   += movedPrincipal;
                }
            }

            // Log transfer volume in the settle token at current NET WL price
            uint256 transferNetSettle = availableToWithdrawal(value);
            if (transferNetSettle > 0) {
                // OUT - from
                _userTxHistory[from].push(
                    TxRecord({
                        kind: 2,
                        timestamp: uint64(block.timestamp),
                        amountSettle: transferNetSettle
                    })
                );
                // IN - to
                _userTxHistory[to].push(
                    TxRecord({
                        kind: 3,
                        timestamp: uint64(block.timestamp),
                        amountSettle: transferNetSettle
                    })
                );
            }
        }

        super._update(from, to, value);
    }

    // ───────── Manual HWM-skim

    function skimPrincipalFeeInDsfLp() external onlyOwner nonReentrant whenNotPaused {
        require(block.number > lastNavTouchBlock, "WL: nav touched");

        uint256 ts = totalSupply();
        if (ts == 0) { HWM_settlePerWL = 0; return; }

        uint256 priceGross = wlPriceGrossSettle();
        if (HWM_settlePerWL == 0) { HWM_settlePerWL = priceGross; return; }

        if (priceGross * DENOM < HWM_settlePerWL * (DENOM + minSkimGainBps)) return;

        uint256 feeSettle = pendingVaultFeeSettle();
        if (feeSettle == 0) { HWM_settlePerWL = priceGross; return; }

        uint256 lpBalance   = dsfLp.balanceOf(address(this));
        uint256 grossSettle = totalGrossSettle();
        if (grossSettle == 0 || lpBalance == 0) { HWM_settlePerWL = priceGross; return; }

        uint256 feeLp = (feeSettle * lpBalance) / grossSettle;
        uint256 balLp = dsfLp.balanceOf(address(this));
        if (feeLp > balLp) feeLp = balLp;

        if (feeLp > 0) {
            dsfLp.safeTransfer(principalTreasury, feeLp);
            ownerCrystallizedSettle += feeSettle;
            _touchNav();
        }

        HWM_settlePerWL = priceGross;
        emit SkimPrincipal(feeSettle, feeLp, priceGross);
    }

    // ───────── emergency sweep (tokens other than DSF LP and pool tokens)

    function sweep(address token, address to, uint256 amount) external onlyOwner {
        require(to != address(0), "WL: bad to");
        for (uint i = 0; i < POOL_ASSETS; i++) {
            require(token != address(tokens[i]), "WL: pool token");
        }
        require(token != address(dsfLp), "WL: dsf lp");
        IERC20(token).safeTransfer(to, amount);
    }

    // ───────── Debug view for calculations

    function debugPreviewAllAndUser(uint256 wlShares)
        external
        view
        returns (uint256 grossAll, uint256 feeUncrystallized, uint256 netAll, uint256 userNet)
    {
        grossAll = totalGrossSettle();
        feeUncrystallized = pendingVaultFeeSettle();
        netAll = grossAll > feeUncrystallized ? grossAll - feeUncrystallized : 0;
        if (totalSupply() == 0) return (grossAll, feeUncrystallized, netAll, 0);
        userNet = (wlShares * netAll) / totalSupply();
    }

    /// @notice Full snapshot for a user:
    /// - principalSettle: deposit principal (“body”) in the settle token
    /// - netNowSettle: current NET (NAV) in the settle token, if fully withdrawn now
    /// - futureIncomeSettle: user’s future income (CRV+CVX+...) in the settle token, already NET
    /// - totalWithFutureSettle: netNow + futureIncome
    /// - perTokenNet: current NET per each of the three tokens [DAI, USDC, USDT]
    /// - walletTokenBalances: user wallet balances in [DAI, USDC, USDT]
    /// - walletTokenAllowances: user allowances for this contract in [DAI, USDC, USDT]
    /// - ethBalance: user’s ETH balance
    function userFullView(address user)
        external
        view
        returns (
            uint256 principalSettle,
            uint256 netNowSettle,
            uint256 futureIncomeSettle,
            uint256 totalWithFutureSettle,
            uint256[POOL_ASSETS] memory perTokenNet,
            uint256[POOL_ASSETS] memory walletTokenBalances,
            uint256[POOL_ASSETS] memory walletTokenAllowances,
            uint256 ethBalance
        )
    {
        principalSettle = userPrincipalSettle[user];

        // Wallet balances and allowances per the three tokens
        for (uint256 i = 0; i < POOL_ASSETS; i++) {
            IERC20 t = tokens[i];
            walletTokenBalances[i]   = t.balanceOf(user);
            walletTokenAllowances[i] = t.allowance(user, address(this));
        }

        // ETH balance
        ethBalance = user.balance;

        uint256 wl = balanceOf(user);
        if (wl == 0) {
            // perTokenNet is zero-initialized by default
            return (
                principalSettle,
                0,
                0,
                0,
                perTokenNet,
                walletTokenBalances,
                walletTokenAllowances,
                ethBalance
            );
        }

        // Current NET in the settle token
        netNowSettle = availableToWithdrawal(wl);

        // Future user yield (NET, after WL fee) in the settle token
        futureIncomeSettle = userFutureIncome(user);

        // Total potential (current + future)
        totalWithFutureSettle = netNowSettle + futureIncomeSettle;

        // NET per each of the three tokens
        perTokenNet = availableToWithdrawalPerToken(wl);
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

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

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

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }

    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // 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;
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)

pragma solidity ^0.8.0;

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

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

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

    bool private _paused;

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

    /**
     * @dev 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 {
        require(!paused(), "Pausable: paused");
    }

    /**
     * @dev Throws if the contract is not paused.
     */
    function _requirePaused() internal view virtual {
        require(paused(), "Pausable: not paused");
    }

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

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

// 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 v5.3.0) (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 {
        _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 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 _callOptionalReturnBool(token, abi.encodeCall(token.transfer, (to, value)));
    }

    /**
     * @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 _callOptionalReturnBool(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.
     *
     * 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 {
        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 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 rely 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 rely 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}.
     * Opposedly, 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 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 {_callOptionalReturnBool} that reverts if call fails to meet the requirements.
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        uint256 returnSize;
        uint256 returnValue;
        assembly ("memory-safe") {
            let success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
            // bubble errors
            if iszero(success) {
                let ptr := mload(0x40)
                returndatacopy(ptr, 0, returndatasize())
                revert(ptr, returndatasize())
            }
            returnSize := returndatasize()
            returnValue := mload(0)
        }

        if (returnSize == 0 ? address(token).code.length == 0 : returnValue != 1) {
            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 silently catches all reverts and returns a bool instead.
     */
    function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
        bool success;
        uint256 returnSize;
        uint256 returnValue;
        assembly ("memory-safe") {
            success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
            returnSize := returndatasize()
            returnValue := mload(0)
        }
        return success && (returnSize == 0 ? address(token).code.length > 0 : returnValue == 1);
    }
}

// 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 v5.4.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.20;

import {IERC20} from "./IERC20.sol";
import {IERC20Metadata} from "./extensions/IERC20Metadata.sol";
import {Context} from "../../utils/Context.sol";
import {IERC20Errors} from "../../interfaces/draft-IERC6093.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * The default value of {decimals} is 18. To change this, you should override
 * this function so it returns a different value.
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC-20
 * applications.
 */
abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors {
    mapping(address account => uint256) private _balances;

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

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * Both values are immutable: they can only be set once during construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

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

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

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

    /// @inheritdoc IERC20
    function totalSupply() public view virtual returns (uint256) {
        return _totalSupply;
    }

    /// @inheritdoc IERC20
    function balanceOf(address account) public view virtual returns (uint256) {
        return _balances[account];
    }

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

    /// @inheritdoc IERC20
    function allowance(address owner, address spender) public view virtual returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `value` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 value) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, value);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Skips emitting an {Approval} event indicating an allowance update. This is not
     * required by the ERC. See {xref-ERC20-_approve-address-address-uint256-bool-}[_approve].
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `value`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `value`.
     */
    function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, value);
        _transfer(from, to, value);
        return true;
    }

    /**
     * @dev Moves a `value` amount of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _transfer(address from, address to, uint256 value) internal {
        if (from == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        if (to == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(from, to, value);
    }

    /**
     * @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from`
     * (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding
     * this function.
     *
     * Emits a {Transfer} event.
     */
    function _update(address from, address to, uint256 value) internal virtual {
        if (from == address(0)) {
            // Overflow check required: The rest of the code assumes that totalSupply never overflows
            _totalSupply += value;
        } else {
            uint256 fromBalance = _balances[from];
            if (fromBalance < value) {
                revert ERC20InsufficientBalance(from, fromBalance, value);
            }
            unchecked {
                // Overflow not possible: value <= fromBalance <= totalSupply.
                _balances[from] = fromBalance - value;
            }
        }

        if (to == address(0)) {
            unchecked {
                // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.
                _totalSupply -= value;
            }
        } else {
            unchecked {
                // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.
                _balances[to] += value;
            }
        }

        emit Transfer(from, to, value);
    }

    /**
     * @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0).
     * Relies on the `_update` mechanism
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead.
     */
    function _mint(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidReceiver(address(0));
        }
        _update(address(0), account, value);
    }

    /**
     * @dev Destroys a `value` amount of tokens from `account`, lowering the total supply.
     * Relies on the `_update` mechanism.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * NOTE: This function is not virtual, {_update} should be overridden instead
     */
    function _burn(address account, uint256 value) internal {
        if (account == address(0)) {
            revert ERC20InvalidSender(address(0));
        }
        _update(account, address(0), value);
    }

    /**
     * @dev Sets `value` as the allowance of `spender` over the `owner`'s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     *
     * Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
     */
    function _approve(address owner, address spender, uint256 value) internal {
        _approve(owner, spender, value, true);
    }

    /**
     * @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.
     *
     * By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by
     * `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any
     * `Approval` event during `transferFrom` operations.
     *
     * Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to
     * true using the following override:
     *
     * ```solidity
     * function _approve(address owner, address spender, uint256 value, bool) internal virtual override {
     *     super._approve(owner, spender, value, true);
     * }
     * ```
     *
     * Requirements are the same as {_approve}.
     */
    function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {
        if (owner == address(0)) {
            revert ERC20InvalidApprover(address(0));
        }
        if (spender == address(0)) {
            revert ERC20InvalidSpender(address(0));
        }
        _allowances[owner][spender] = value;
        if (emitEvent) {
            emit Approval(owner, spender, value);
        }
    }

    /**
     * @dev Updates `owner`'s allowance for `spender` based on spent `value`.
     *
     * Does not update the allowance value in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Does not emit an {Approval} event.
     */
    function _spendAllowance(address owner, address spender, uint256 value) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance < type(uint256).max) {
            if (currentAllowance < value) {
                revert ERC20InsufficientAllowance(spender, currentAllowance, value);
            }
            unchecked {
                _approve(owner, spender, currentAllowance - value, false);
            }
        }
    }
}

// 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 v5.4.0) (interfaces/draft-IERC6093.sol)
pragma solidity >=0.8.4;

/**
 * @dev Standard ERC-20 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-20 tokens.
 */
interface IERC20Errors {
    /**
     * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param balance Current balance for the interacting account.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC20InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC20InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     * @param allowance Amount of tokens a `spender` is allowed to operate with.
     * @param needed Minimum amount required to perform a transfer.
     */
    error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC20InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `spender` to be approved. Used in approvals.
     * @param spender Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC20InvalidSpender(address spender);
}

/**
 * @dev Standard ERC-721 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-721 tokens.
 */
interface IERC721Errors {
    /**
     * @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in ERC-20.
     * Used in balance queries.
     * @param owner Address of the current owner of a token.
     */
    error ERC721InvalidOwner(address owner);

    /**
     * @dev Indicates a `tokenId` whose `owner` is the zero address.
     * @param tokenId Identifier number of a token.
     */
    error ERC721NonexistentToken(uint256 tokenId);

    /**
     * @dev Indicates an error related to the ownership over a particular token. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param tokenId Identifier number of a token.
     * @param owner Address of the current owner of a token.
     */
    error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC721InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC721InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     * @param tokenId Identifier number of a token.
     */
    error ERC721InsufficientApproval(address operator, uint256 tokenId);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC721InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC721InvalidOperator(address operator);
}

/**
 * @dev Standard ERC-1155 Errors
 * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-1155 tokens.
 */
interface IERC1155Errors {
    /**
     * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     * @param balance Current balance for the interacting account.
     * @param needed Minimum amount required to perform a transfer.
     * @param tokenId Identifier number of a token.
     */
    error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);

    /**
     * @dev Indicates a failure with the token `sender`. Used in transfers.
     * @param sender Address whose tokens are being transferred.
     */
    error ERC1155InvalidSender(address sender);

    /**
     * @dev Indicates a failure with the token `receiver`. Used in transfers.
     * @param receiver Address to which tokens are being transferred.
     */
    error ERC1155InvalidReceiver(address receiver);

    /**
     * @dev Indicates a failure with the `operator`’s approval. Used in transfers.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     * @param owner Address of the current owner of a token.
     */
    error ERC1155MissingApprovalForAll(address operator, address owner);

    /**
     * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
     * @param approver Address initiating an approval operation.
     */
    error ERC1155InvalidApprover(address approver);

    /**
     * @dev Indicates a failure with the `operator` to be approved. Used in approvals.
     * @param operator Address that may be allowed to operate on tokens without being their owner.
     */
    error ERC1155InvalidOperator(address operator);

    /**
     * @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
     * Used in batch transfers.
     * @param idsLength Length of the array of token identifiers
     * @param valuesLength Length of the array of token amounts
     */
    error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}

// 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) (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity >=0.6.2;

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

/**
 * @dev Interface for the optional metadata functions from the ERC-20 standard.
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

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

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

// 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) (interfaces/IERC20.sol)

pragma solidity >=0.4.16;

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

// 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);
}