// SPDX-License-Identifier: BUSL-1.1

pragma solidity 0.8.24;

import "../Interfaces/IAddRemoveManagers.sol";
import "../Interfaces/IAddressesRegistry.sol";
import "../Interfaces/ITroveNFT.sol";

contract AddRemoveManagers is IAddRemoveManagers {
    ITroveNFT internal immutable troveNFT;

    struct RemoveManagerReceiver {
        address manager;
        address receiver;
    }

    /*
     * Mapping from TroveId to granted address for operations that "give" money to the trove (add collateral, pay debt).
     * Useful for instance for cold/hot wallet setups.
     * If its value is zero address, any address is allowed to do those operations on behalf of trove owner.
     * Otherwise, only the address in this mapping (and the trove owner) will be allowed.
     * To restrict this permission to no one, trove owner should be set in this mapping.
     */
    mapping(uint256 => address) public addManagerOf;

    /*
     * Mapping from TroveId to granted addresses for operations that "withdraw" money from the trove (withdraw collateral, borrow),
     * and for each of those addresses another address for the receiver of those withdrawn funds.
     * Useful for instance for cold/hot wallet setups or for automations.
     * Only the address in this mapping, if any, and the trove owner, will be allowed.
     * Therefore, by default this permission is restricted to no one.
     * If the receiver is zero, the owner is assumed as the receiver.
     */
    mapping(uint256 => RemoveManagerReceiver) public removeManagerReceiverOf;

    error EmptyManager();
    error NotBorrower();
    error NotOwnerNorAddManager();
    error NotOwnerNorRemoveManager();

    event TroveNFTAddressChanged(address _newTroveNFTAddress);
    event AddManagerUpdated(uint256 indexed _troveId, address _newAddManager);
    event RemoveManagerAndReceiverUpdated(uint256 indexed _troveId, address _newRemoveManager, address _newReceiver);

    constructor(IAddressesRegistry _addressesRegistry) {
        troveNFT = _addressesRegistry.troveNFT();
        emit TroveNFTAddressChanged(address(troveNFT));
    }

    function setAddManager(uint256 _troveId, address _manager) external {
        _requireCallerIsBorrower(_troveId);
        _setAddManager(_troveId, _manager);
    }

    function _setAddManager(uint256 _troveId, address _manager) internal {
        addManagerOf[_troveId] = _manager;
        emit AddManagerUpdated(_troveId, _manager);
    }

    function setRemoveManager(uint256 _troveId, address _manager) external {
        setRemoveManagerWithReceiver(_troveId, _manager, troveNFT.ownerOf(_troveId));
    }

    function setRemoveManagerWithReceiver(uint256 _troveId, address _manager, address _receiver) public {
        _requireCallerIsBorrower(_troveId);
        _setRemoveManagerAndReceiver(_troveId, _manager, _receiver);
    }

    function _setRemoveManagerAndReceiver(uint256 _troveId, address _manager, address _receiver) internal {
        _requireNonZeroManagerUnlessWiping(_manager, _receiver);
        removeManagerReceiverOf[_troveId].manager = _manager;
        removeManagerReceiverOf[_troveId].receiver = _receiver;
        emit RemoveManagerAndReceiverUpdated(_troveId, _manager, _receiver);
    }

    function _wipeAddRemoveManagers(uint256 _troveId) internal {
        delete addManagerOf[_troveId];
        delete removeManagerReceiverOf[_troveId];
        emit AddManagerUpdated(_troveId, address(0));
        emit RemoveManagerAndReceiverUpdated(_troveId, address(0), address(0));
    }

    function _requireNonZeroManagerUnlessWiping(address _manager, address _receiver) internal pure {
        if (_manager == address(0) && _receiver != address(0)) {
            revert EmptyManager();
        }
    }

    function _requireCallerIsBorrower(uint256 _troveId) internal view {
        if (msg.sender != troveNFT.ownerOf(_troveId)) {
            revert NotBorrower();
        }
    }

    function _requireSenderIsOwnerOrAddManager(uint256 _troveId, address _owner) internal view {
        address addManager = addManagerOf[_troveId];
        if (msg.sender != _owner && addManager != address(0) && msg.sender != addManager) {
            revert NotOwnerNorAddManager();
        }
    }

    function _requireSenderIsOwnerOrRemoveManagerAndGetReceiver(uint256 _troveId, address _owner)
        internal
        view
        returns (address)
    {
        address manager = removeManagerReceiverOf[_troveId].manager;
        address receiver = removeManagerReceiverOf[_troveId].receiver;
        if (msg.sender != _owner && msg.sender != manager) {
            revert NotOwnerNorRemoveManager();
        }
        if (receiver == address(0) || msg.sender != manager) {
            return _owner;
        }
        return receiver;
    }
}

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

pragma solidity ^0.8.1;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     *
     * Furthermore, `isContract` will also return true if the target contract within
     * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
     * which only has an effect at the end of a transaction.
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://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/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) 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(errorMessage);
        }
    }
}

// SPDX-License-Identifier: MIT

pragma solidity 0.8.24;

type BatchId is address;

using {equals as ==, notEquals as !=, isZero, isNotZero} for BatchId global;

function equals(BatchId a, BatchId b) pure returns (bool) {
    return BatchId.unwrap(a) == BatchId.unwrap(b);
}

function notEquals(BatchId a, BatchId b) pure returns (bool) {
    return !(a == b);
}

function isZero(BatchId x) pure returns (bool) {
    return x == BATCH_ID_ZERO;
}

function isNotZero(BatchId x) pure returns (bool) {
    return !x.isZero();
}

BatchId constant BATCH_ID_ZERO = BatchId.wrap(address(0));

// SPDX-License-Identifier: BUSL-1.1

pragma solidity 0.8.24;

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

import "./Interfaces/IBorrowerOperations.sol";
import "./Interfaces/IAddressesRegistry.sol";
import "./Interfaces/ITroveManager.sol";
import "./Interfaces/IBoldToken.sol";
import "./Interfaces/ICollSurplusPool.sol";
import "./Interfaces/ISortedTroves.sol";
import "./Dependencies/LiquityBase.sol";
import "./Dependencies/AddRemoveManagers.sol";
import "./Types/LatestTroveData.sol";
import "./Types/LatestBatchData.sol";

contract BorrowerOperations is LiquityBase, AddRemoveManagers, IBorrowerOperations {
    using SafeERC20 for IERC20;

    // --- Connected contract declarations ---

    IERC20 internal immutable collToken;
    ITroveManager internal troveManager;
    address internal gasPoolAddress;
    ICollSurplusPool internal collSurplusPool;
    IBoldToken internal boldToken;
    // A doubly linked list of Troves, sorted by their collateral ratios
    ISortedTroves internal sortedTroves;
    // Wrapped ETH for liquidation reserve (gas compensation)
    IWETH internal immutable WETH;

    // Critical system collateral ratio. If the system's total collateral ratio (TCR) falls below the CCR, some borrowing operation restrictions are applied
    uint256 public immutable CCR;

    // Shutdown system collateral ratio. If the system's total collateral ratio (TCR) for a given collateral falls below the SCR,
    // the protocol triggers the shutdown of the borrow market and permanently disables all borrowing operations except for closing Troves.
    uint256 public immutable SCR;
    bool public hasBeenShutDown;

    // Minimum collateral ratio for individual troves
    uint256 public immutable MCR;

    /*
    * Mapping from TroveId to individual delegate for interest rate setting.
    *
    * This address then has the ability to update the borrower’s interest rate, but not change its debt or collateral.
    * Useful for instance for cold/hot wallet setups.
    */
    mapping(uint256 => InterestIndividualDelegate) private interestIndividualDelegateOf;

    /*
     * Mapping from TroveId to granted address for interest rate setting (batch manager).
     *
     * Batch managers set the interest rate for every Trove in the batch. The interest rate is the same for all Troves in the batch.
     */
    mapping(uint256 => address) public interestBatchManagerOf;

    // List of registered Interest Batch Managers
    mapping(address => InterestBatchManager) private interestBatchManagers;

    /* --- Variable container structs  ---

    Used to hold, return and assign variables inside a function, in order to avoid the error:
    "CompilerError: Stack too deep". */

    struct OpenTroveVars {
        ITroveManager troveManager;
        uint256 troveId;
        TroveChange change;
        LatestBatchData batch;
    }

    struct LocalVariables_openTrove {
        ITroveManager troveManager;
        IActivePool activePool;
        IBoldToken boldToken;
        uint256 troveId;
        uint256 price;
        uint256 avgInterestRate;
        uint256 entireDebt;
        uint256 ICR;
        uint256 newTCR;
        bool newOracleFailureDetected;
    }

    struct LocalVariables_adjustTrove {
        IActivePool activePool;
        IBoldToken boldToken;
        LatestTroveData trove;
        uint256 price;
        bool isBelowCriticalThreshold;
        uint256 newICR;
        uint256 newDebt;
        uint256 newColl;
        bool newOracleFailureDetected;
    }

    struct LocalVariables_setInterestBatchManager {
        ITroveManager troveManager;
        IActivePool activePool;
        ISortedTroves sortedTroves;
        address oldBatchManager;
        LatestTroveData trove;
        LatestBatchData oldBatch;
        LatestBatchData newBatch;
    }

    struct LocalVariables_removeFromBatch {
        ITroveManager troveManager;
        ISortedTroves sortedTroves;
        address batchManager;
        LatestTroveData trove;
        LatestBatchData batch;
        uint256 newBatchDebt;
    }

    error IsShutDown();
    error TCRNotBelowSCR();
    error ZeroAdjustment();
    error NotOwnerNorInterestManager();
    error TroveInBatch();
    error TroveNotInBatch();
    error InterestNotInRange();
    error BatchInterestRateChangePeriodNotPassed();
    error DelegateInterestRateChangePeriodNotPassed();
    error TroveExists();
    error TroveNotOpen();
    error TroveNotActive();
    error TroveNotZombie();
    error TroveWithZeroDebt();
    error UpfrontFeeTooHigh();
    error ICRBelowMCR();
    error RepaymentNotMatchingCollWithdrawal();
    error TCRBelowCCR();
    error DebtBelowMin();
    error CollWithdrawalTooHigh();
    error NotEnoughBoldBalance();
    error InterestRateTooLow();
    error InterestRateTooHigh();
    error InterestRateNotNew();
    error InvalidInterestBatchManager();
    error BatchManagerExists();
    error BatchManagerNotNew();
    error NewFeeNotLower();
    error CallerNotTroveManager();
    error CallerNotPriceFeed();
    error MinGeMax();
    error AnnualManagementFeeTooHigh();
    error MinInterestRateChangePeriodTooLow();
    error NewOracleFailureDetected();

    event TroveManagerAddressChanged(address _newTroveManagerAddress);
    event GasPoolAddressChanged(address _gasPoolAddress);
    event CollSurplusPoolAddressChanged(address _collSurplusPoolAddress);
    event SortedTrovesAddressChanged(address _sortedTrovesAddress);
    event BoldTokenAddressChanged(address _boldTokenAddress);

    event ShutDown(uint256 _tcr);

    constructor(IAddressesRegistry _addressesRegistry)
        AddRemoveManagers(_addressesRegistry)
        LiquityBase(_addressesRegistry)
    {
        // This makes impossible to open a trove with zero withdrawn Bold
        assert(MIN_DEBT > 0);

        collToken = _addressesRegistry.collToken();

        WETH = _addressesRegistry.WETH();

        CCR = _addressesRegistry.CCR();
        SCR = _addressesRegistry.SCR();
        MCR = _addressesRegistry.MCR();

        troveManager = _addressesRegistry.troveManager();
        gasPoolAddress = _addressesRegistry.gasPoolAddress();
        collSurplusPool = _addressesRegistry.collSurplusPool();
        sortedTroves = _addressesRegistry.sortedTroves();
        boldToken = _addressesRegistry.boldToken();

        emit TroveManagerAddressChanged(address(troveManager));
        emit GasPoolAddressChanged(gasPoolAddress);
        emit CollSurplusPoolAddressChanged(address(collSurplusPool));
        emit SortedTrovesAddressChanged(address(sortedTroves));
        emit BoldTokenAddressChanged(address(boldToken));

        // Allow funds movements between Liquity contracts
        collToken.approve(address(activePool), type(uint256).max);
    }

    // --- Borrower Trove Operations ---

    function openTrove(
        address _owner,
        uint256 _ownerIndex,
        uint256 _collAmount,
        uint256 _boldAmount,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _annualInterestRate,
        uint256 _maxUpfrontFee,
        address _addManager,
        address _removeManager,
        address _receiver
    ) external override returns (uint256) {
        _requireValidAnnualInterestRate(_annualInterestRate);

        OpenTroveVars memory vars;

        vars.troveId = _openTrove(
            _owner,
            _ownerIndex,
            _collAmount,
            _boldAmount,
            _annualInterestRate,
            address(0),
            0,
            0,
            _maxUpfrontFee,
            _addManager,
            _removeManager,
            _receiver,
            vars.change
        );

        // Set the stored Trove properties and mint the NFT
        troveManager.onOpenTrove(_owner, vars.troveId, vars.change, _annualInterestRate);

        sortedTroves.insert(vars.troveId, _annualInterestRate, _upperHint, _lowerHint);

        return vars.troveId;
    }

    function openTroveAndJoinInterestBatchManager(OpenTroveAndJoinInterestBatchManagerParams calldata _params)
        external
        override
        returns (uint256)
    {
        _requireValidInterestBatchManager(_params.interestBatchManager);

        OpenTroveVars memory vars;
        vars.troveManager = troveManager;

        vars.batch = vars.troveManager.getLatestBatchData(_params.interestBatchManager);

        // We set old weighted values here, as it’s only necessary for batches, so we don’t need to pass them to _openTrove func
        vars.change.batchAccruedManagementFee = vars.batch.accruedManagementFee;
        vars.change.oldWeightedRecordedDebt = vars.batch.weightedRecordedDebt;
        vars.change.oldWeightedRecordedBatchManagementFee = vars.batch.weightedRecordedBatchManagementFee;
        vars.troveId = _openTrove(
            _params.owner,
            _params.ownerIndex,
            _params.collAmount,
            _params.boldAmount,
            vars.batch.annualInterestRate,
            _params.interestBatchManager,
            vars.batch.entireDebtWithoutRedistribution,
            vars.batch.annualManagementFee,
            _params.maxUpfrontFee,
            _params.addManager,
            _params.removeManager,
            _params.receiver,
            vars.change
        );

        interestBatchManagerOf[vars.troveId] = _params.interestBatchManager;

        // Set the stored Trove properties and mint the NFT
        vars.troveManager.onOpenTroveAndJoinBatch(
            _params.owner,
            vars.troveId,
            vars.change,
            _params.interestBatchManager,
            vars.batch.entireCollWithoutRedistribution,
            vars.batch.entireDebtWithoutRedistribution
        );

        sortedTroves.insertIntoBatch(
            vars.troveId,
            BatchId.wrap(_params.interestBatchManager),
            vars.batch.annualInterestRate,
            _params.upperHint,
            _params.lowerHint
        );

        return vars.troveId;
    }

    function _openTrove(
        address _owner,
        uint256 _ownerIndex,
        uint256 _collAmount,
        uint256 _boldAmount,
        uint256 _annualInterestRate,
        address _interestBatchManager,
        uint256 _batchEntireDebt,
        uint256 _batchManagementAnnualFee,
        uint256 _maxUpfrontFee,
        address _addManager,
        address _removeManager,
        address _receiver,
        TroveChange memory _change
    ) internal returns (uint256) {
        _requireIsNotShutDown();

        LocalVariables_openTrove memory vars;

        // stack too deep not allowing to reuse troveManager from outer functions
        vars.troveManager = troveManager;
        vars.activePool = activePool;
        vars.boldToken = boldToken;

        vars.price = _requireOraclesLive();

        // --- Checks ---

        vars.troveId = uint256(keccak256(abi.encode(_owner, _ownerIndex)));
        _requireTroveDoesNotExists(vars.troveManager, vars.troveId);

        _change.collIncrease = _collAmount;
        _change.debtIncrease = _boldAmount;

        // For simplicity, we ignore the fee when calculating the approx. interest rate
        _change.newWeightedRecordedDebt = (_batchEntireDebt + _change.debtIncrease) * _annualInterestRate;

        vars.avgInterestRate = vars.activePool.getNewApproxAvgInterestRateFromTroveChange(_change);
        _change.upfrontFee = _calcUpfrontFee(_change.debtIncrease, vars.avgInterestRate);
        _requireUserAcceptsUpfrontFee(_change.upfrontFee, _maxUpfrontFee);

        vars.entireDebt = _change.debtIncrease + _change.upfrontFee;
        _requireAtLeastMinDebt(vars.entireDebt);

        // Recalculate newWeightedRecordedDebt, now taking into account the upfront fee, and the batch fee if needed
        if (_interestBatchManager == address(0)) {
            _change.newWeightedRecordedDebt = vars.entireDebt * _annualInterestRate;
        } else {
            // old values have been set outside, before calling this function
            _change.newWeightedRecordedDebt = (_batchEntireDebt + vars.entireDebt) * _annualInterestRate;
            _change.newWeightedRecordedBatchManagementFee =
                (_batchEntireDebt + vars.entireDebt) * _batchManagementAnnualFee;
        }

        // ICR is based on the requested Bold amount + upfront fee.
        vars.ICR = LiquityMath._computeCR(_collAmount, vars.entireDebt, vars.price);
        _requireICRisAboveMCR(vars.ICR);

        vars.newTCR = _getNewTCRFromTroveChange(_change, vars.price);
        _requireNewTCRisAboveCCR(vars.newTCR);

        // --- Effects & interactions ---

        // Set add/remove managers
        _setAddManager(vars.troveId, _addManager);
        _setRemoveManagerAndReceiver(vars.troveId, _removeManager, _receiver);

        vars.activePool.mintAggInterestAndAccountForTroveChange(_change, _interestBatchManager);

        // Pull coll tokens from sender and move them to the Active Pool
        _pullCollAndSendToActivePool(vars.activePool, _collAmount);

        // Mint the requested _boldAmount to the borrower and mint the gas comp to the GasPool
        vars.boldToken.mint(msg.sender, _boldAmount);
        WETH.transferFrom(msg.sender, gasPoolAddress, ETH_GAS_COMPENSATION);

        return vars.troveId;
    }

    // Send collateral to a trove
    function addColl(uint256 _troveId, uint256 _collAmount) external override {
        ITroveManager troveManagerCached = troveManager;
        _requireTroveIsActive(troveManagerCached, _troveId);

        TroveChange memory troveChange;
        troveChange.collIncrease = _collAmount;

        _adjustTrove(
            troveManagerCached,
            _troveId,
            troveChange,
            0 // _maxUpfrontFee
        );
    }

    // Withdraw collateral from a trove
    function withdrawColl(uint256 _troveId, uint256 _collWithdrawal) external override {
        ITroveManager troveManagerCached = troveManager;
        _requireTroveIsActive(troveManagerCached, _troveId);

        TroveChange memory troveChange;
        troveChange.collDecrease = _collWithdrawal;

        _adjustTrove(
            troveManagerCached,
            _troveId,
            troveChange,
            0 // _maxUpfrontFee
        );
    }

    // Withdraw Bold tokens from a trove: mint new Bold tokens to the owner, and increase the trove's debt accordingly
    function withdrawBold(uint256 _troveId, uint256 _boldAmount, uint256 _maxUpfrontFee) external override {
        ITroveManager troveManagerCached = troveManager;
        _requireTroveIsActive(troveManagerCached, _troveId);

        TroveChange memory troveChange;
        troveChange.debtIncrease = _boldAmount;
        _adjustTrove(troveManagerCached, _troveId, troveChange, _maxUpfrontFee);
    }

    // Repay Bold tokens to a Trove: Burn the repaid Bold tokens, and reduce the trove's debt accordingly
    function repayBold(uint256 _troveId, uint256 _boldAmount) external override {
        ITroveManager troveManagerCached = troveManager;
        _requireTroveIsActive(troveManagerCached, _troveId);

        TroveChange memory troveChange;
        troveChange.debtDecrease = _boldAmount;

        _adjustTrove(
            troveManagerCached,
            _troveId,
            troveChange,
            0 // _maxUpfrontFee
        );
    }

    function _initTroveChange(
        TroveChange memory _troveChange,
        uint256 _collChange,
        bool _isCollIncrease,
        uint256 _boldChange,
        bool _isDebtIncrease
    ) internal pure {
        if (_isCollIncrease) {
            _troveChange.collIncrease = _collChange;
        } else {
            _troveChange.collDecrease = _collChange;
        }

        if (_isDebtIncrease) {
            _troveChange.debtIncrease = _boldChange;
        } else {
            _troveChange.debtDecrease = _boldChange;
        }
    }

    function adjustTrove(
        uint256 _troveId,
        uint256 _collChange,
        bool _isCollIncrease,
        uint256 _boldChange,
        bool _isDebtIncrease,
        uint256 _maxUpfrontFee
    ) external override {
        ITroveManager troveManagerCached = troveManager;
        _requireTroveIsActive(troveManagerCached, _troveId);

        TroveChange memory troveChange;
        _initTroveChange(troveChange, _collChange, _isCollIncrease, _boldChange, _isDebtIncrease);
        _adjustTrove(troveManagerCached, _troveId, troveChange, _maxUpfrontFee);
    }

    function adjustZombieTrove(
        uint256 _troveId,
        uint256 _collChange,
        bool _isCollIncrease,
        uint256 _boldChange,
        bool _isDebtIncrease,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external override {
        ITroveManager troveManagerCached = troveManager;
        _requireTroveIsZombie(troveManagerCached, _troveId);

        TroveChange memory troveChange;
        _initTroveChange(troveChange, _collChange, _isCollIncrease, _boldChange, _isDebtIncrease);
        _adjustTrove(troveManagerCached, _troveId, troveChange, _maxUpfrontFee);

        troveManagerCached.setTroveStatusToActive(_troveId);

        address batchManager = interestBatchManagerOf[_troveId];
        uint256 batchAnnualInterestRate;
        if (batchManager != address(0)) {
            LatestBatchData memory batch = troveManagerCached.getLatestBatchData(batchManager);
            batchAnnualInterestRate = batch.annualInterestRate;
        }
        _reInsertIntoSortedTroves(
            _troveId,
            troveManagerCached.getTroveAnnualInterestRate(_troveId),
            _upperHint,
            _lowerHint,
            batchManager,
            batchAnnualInterestRate
        );
    }

    function adjustTroveInterestRate(
        uint256 _troveId,
        uint256 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external {
        _requireIsNotShutDown();

        ITroveManager troveManagerCached = troveManager;

        _requireValidAnnualInterestRate(_newAnnualInterestRate);
        _requireIsNotInBatch(_troveId);
        _requireSenderIsOwnerOrInterestManager(_troveId);
        _requireTroveIsActive(troveManagerCached, _troveId);

        LatestTroveData memory trove = troveManagerCached.getLatestTroveData(_troveId);
        _requireValidDelegateAdustment(_troveId, trove.lastInterestRateAdjTime, _newAnnualInterestRate);
        _requireAnnualInterestRateIsNew(trove.annualInterestRate, _newAnnualInterestRate);

        uint256 newDebt = trove.entireDebt;

        TroveChange memory troveChange;
        troveChange.appliedRedistBoldDebtGain = trove.redistBoldDebtGain;
        troveChange.appliedRedistCollGain = trove.redistCollGain;
        troveChange.newWeightedRecordedDebt = newDebt * _newAnnualInterestRate;
        troveChange.oldWeightedRecordedDebt = trove.weightedRecordedDebt;

        // Apply upfront fee on premature adjustments
        if (
            trove.annualInterestRate != _newAnnualInterestRate
                && block.timestamp < trove.lastInterestRateAdjTime + INTEREST_RATE_ADJ_COOLDOWN
        ) {
            newDebt = _applyUpfrontFee(trove.entireColl, newDebt, troveChange, _maxUpfrontFee);
        }

        // Recalculate newWeightedRecordedDebt, now taking into account the upfront fee
        troveChange.newWeightedRecordedDebt = newDebt * _newAnnualInterestRate;

        activePool.mintAggInterestAndAccountForTroveChange(troveChange, address(0));

        sortedTroves.reInsert(_troveId, _newAnnualInterestRate, _upperHint, _lowerHint);
        troveManagerCached.onAdjustTroveInterestRate(
            _troveId, trove.entireColl, newDebt, _newAnnualInterestRate, troveChange
        );
    }

    /*
    * _adjustTrove(): Alongside a debt change, this function can perform either a collateral top-up or a collateral withdrawal.
    */
    function _adjustTrove(
        ITroveManager _troveManager,
        uint256 _troveId,
        TroveChange memory _troveChange,
        uint256 _maxUpfrontFee
    ) internal {
        _requireIsNotShutDown();

        LocalVariables_adjustTrove memory vars;
        vars.activePool = activePool;
        vars.boldToken = boldToken;

        vars.price = _requireOraclesLive();
        vars.isBelowCriticalThreshold = _checkBelowCriticalThreshold(vars.price, CCR);

        // --- Checks ---

        _requireTroveIsOpen(_troveManager, _troveId);

        address owner = troveNFT.ownerOf(_troveId);
        address receiver = owner; // If it’s a withdrawal, and manager has receive privilege, manager would be the receiver

        if (_troveChange.collDecrease > 0 || _troveChange.debtIncrease > 0) {
            receiver = _requireSenderIsOwnerOrRemoveManagerAndGetReceiver(_troveId, owner);
        }

        if (_troveChange.collIncrease > 0 || _troveChange.debtDecrease > 0) {
            _requireSenderIsOwnerOrAddManager(_troveId, owner);
        }

        vars.trove = _troveManager.getLatestTroveData(_troveId);

        // When the adjustment is a debt repayment, check it's a valid amount and that the caller has enough Bold
        if (_troveChange.debtDecrease > 0) {
            uint256 maxRepayment = vars.trove.entireDebt > MIN_DEBT ? vars.trove.entireDebt - MIN_DEBT : 0;
            if (_troveChange.debtDecrease > maxRepayment) {
                _troveChange.debtDecrease = maxRepayment;
            }
            _requireSufficientBoldBalance(vars.boldToken, msg.sender, _troveChange.debtDecrease);
        }

        _requireNonZeroAdjustment(_troveChange);

        // When the adjustment is a collateral withdrawal, check that it's no more than the Trove's entire collateral
        if (_troveChange.collDecrease > 0) {
            _requireValidCollWithdrawal(vars.trove.entireColl, _troveChange.collDecrease);
        }

        vars.newColl = vars.trove.entireColl + _troveChange.collIncrease - _troveChange.collDecrease;
        vars.newDebt = vars.trove.entireDebt + _troveChange.debtIncrease - _troveChange.debtDecrease;

        address batchManager = interestBatchManagerOf[_troveId];
        bool isTroveInBatch = batchManager != address(0);
        LatestBatchData memory batch;
        uint256 batchFutureDebt;
        if (isTroveInBatch) {
            batch = _troveManager.getLatestBatchData(batchManager);

            batchFutureDebt = batch.entireDebtWithoutRedistribution + vars.trove.redistBoldDebtGain
                + _troveChange.debtIncrease - _troveChange.debtDecrease;

            _troveChange.appliedRedistBoldDebtGain = vars.trove.redistBoldDebtGain;
            _troveChange.appliedRedistCollGain = vars.trove.redistCollGain;
            _troveChange.batchAccruedManagementFee = batch.accruedManagementFee;
            _troveChange.oldWeightedRecordedDebt = batch.weightedRecordedDebt;
            _troveChange.newWeightedRecordedDebt = batchFutureDebt * batch.annualInterestRate;
            _troveChange.oldWeightedRecordedBatchManagementFee = batch.weightedRecordedBatchManagementFee;
            _troveChange.newWeightedRecordedBatchManagementFee = batchFutureDebt * batch.annualManagementFee;
        } else {
            _troveChange.appliedRedistBoldDebtGain = vars.trove.redistBoldDebtGain;
            _troveChange.appliedRedistCollGain = vars.trove.redistCollGain;
            _troveChange.oldWeightedRecordedDebt = vars.trove.weightedRecordedDebt;
            _troveChange.newWeightedRecordedDebt = vars.newDebt * vars.trove.annualInterestRate;
        }

        // Pay an upfront fee on debt increases
        if (_troveChange.debtIncrease > 0) {
            uint256 avgInterestRate = vars.activePool.getNewApproxAvgInterestRateFromTroveChange(_troveChange);
            _troveChange.upfrontFee = _calcUpfrontFee(_troveChange.debtIncrease, avgInterestRate);
            _requireUserAcceptsUpfrontFee(_troveChange.upfrontFee, _maxUpfrontFee);

            vars.newDebt += _troveChange.upfrontFee;
            if (isTroveInBatch) {
                batchFutureDebt += _troveChange.upfrontFee;
                // Recalculate newWeightedRecordedDebt, now taking into account the upfront fee
                _troveChange.newWeightedRecordedDebt = batchFutureDebt * batch.annualInterestRate;
                _troveChange.newWeightedRecordedBatchManagementFee = batchFutureDebt * batch.annualManagementFee;
            } else {
                // Recalculate newWeightedRecordedDebt, now taking into account the upfront fee
                _troveChange.newWeightedRecordedDebt = vars.newDebt * vars.trove.annualInterestRate;
            }
        }

        // Make sure the Trove doesn't end up zombie
        // Now the max repayment is capped to stay above MIN_DEBT, so this only applies to adjustZombieTrove
        _requireAtLeastMinDebt(vars.newDebt);

        vars.newICR = LiquityMath._computeCR(vars.newColl, vars.newDebt, vars.price);

        // Check the adjustment satisfies all conditions for the current system mode
        _requireValidAdjustmentInCurrentMode(_troveChange, vars);

        // --- Effects and interactions ---

        if (isTroveInBatch) {
            _troveManager.onAdjustTroveInsideBatch(
                _troveId,
                vars.newColl,
                vars.newDebt,
                _troveChange,
                batchManager,
                batch.entireCollWithoutRedistribution,
                batch.entireDebtWithoutRedistribution
            );
        } else {
            _troveManager.onAdjustTrove(_troveId, vars.newColl, vars.newDebt, _troveChange);
        }

        vars.activePool.mintAggInterestAndAccountForTroveChange(_troveChange, batchManager);
        _moveTokensFromAdjustment(receiver, _troveChange, vars.boldToken, vars.activePool);
    }

    function closeTrove(uint256 _troveId) external override {
        ITroveManager troveManagerCached = troveManager;
        IActivePool activePoolCached = activePool;
        IBoldToken boldTokenCached = boldToken;

        // --- Checks ---

        address owner = troveNFT.ownerOf(_troveId);
        address receiver = _requireSenderIsOwnerOrRemoveManagerAndGetReceiver(_troveId, owner);
        _requireTroveIsOpen(troveManagerCached, _troveId);

        LatestTroveData memory trove = troveManagerCached.getLatestTroveData(_troveId);

        // The borrower must repay their entire debt including accrued interest, batch fee and redist. gains
        _requireSufficientBoldBalance(boldTokenCached, msg.sender, trove.entireDebt);

        TroveChange memory troveChange;
        troveChange.appliedRedistBoldDebtGain = trove.redistBoldDebtGain;
        troveChange.appliedRedistCollGain = trove.redistCollGain;
        troveChange.collDecrease = trove.entireColl;
        troveChange.debtDecrease = trove.entireDebt;

        address batchManager = interestBatchManagerOf[_troveId];
        LatestBatchData memory batch;
        if (batchManager != address(0)) {
            batch = troveManagerCached.getLatestBatchData(batchManager);
            uint256 batchFutureDebt =
                batch.entireDebtWithoutRedistribution - (trove.entireDebt - trove.redistBoldDebtGain);
            troveChange.batchAccruedManagementFee = batch.accruedManagementFee;
            troveChange.oldWeightedRecordedDebt = batch.weightedRecordedDebt;
            troveChange.newWeightedRecordedDebt = batchFutureDebt * batch.annualInterestRate;
            troveChange.oldWeightedRecordedBatchManagementFee = batch.weightedRecordedBatchManagementFee;
            troveChange.newWeightedRecordedBatchManagementFee = batchFutureDebt * batch.annualManagementFee;
        } else {
            troveChange.oldWeightedRecordedDebt = trove.weightedRecordedDebt;
            // troveChange.newWeightedRecordedDebt = 0;
        }

        (uint256 price,) = priceFeed.fetchPrice();
        uint256 newTCR = _getNewTCRFromTroveChange(troveChange, price);
        if (!hasBeenShutDown) _requireNewTCRisAboveCCR(newTCR);

        troveManagerCached.onCloseTrove(
            _troveId,
            troveChange,
            batchManager,
            batch.entireCollWithoutRedistribution,
            batch.entireDebtWithoutRedistribution
        );

        // If trove is in batch
        if (batchManager != address(0)) {
            // Unlink here in BorrowerOperations
            interestBatchManagerOf[_troveId] = address(0);
        }

        activePoolCached.mintAggInterestAndAccountForTroveChange(troveChange, batchManager);

        // Return ETH gas compensation
        WETH.transferFrom(gasPoolAddress, receiver, ETH_GAS_COMPENSATION);
        // Burn the remainder of the Trove's entire debt from the user
        boldTokenCached.burn(msg.sender, trove.entireDebt);

        // Send the collateral back to the user
        activePoolCached.sendColl(receiver, trove.entireColl);

        _wipeTroveMappings(_troveId);
    }

    function applyPendingDebt(uint256 _troveId, uint256 _lowerHint, uint256 _upperHint) public {
        _requireIsNotShutDown();

        ITroveManager troveManagerCached = troveManager;

        _requireTroveIsOpen(troveManagerCached, _troveId);

        LatestTroveData memory trove = troveManagerCached.getLatestTroveData(_troveId);
        _requireNonZeroDebt(trove.entireDebt);

        TroveChange memory change;
        change.appliedRedistBoldDebtGain = trove.redistBoldDebtGain;
        change.appliedRedistCollGain = trove.redistCollGain;

        address batchManager = interestBatchManagerOf[_troveId];
        LatestBatchData memory batch;

        if (batchManager == address(0)) {
            change.oldWeightedRecordedDebt = trove.weightedRecordedDebt;
            change.newWeightedRecordedDebt = trove.entireDebt * trove.annualInterestRate;
        } else {
            batch = troveManagerCached.getLatestBatchData(batchManager);
            change.batchAccruedManagementFee = batch.accruedManagementFee;
            change.oldWeightedRecordedDebt = batch.weightedRecordedDebt;
            change.newWeightedRecordedDebt =
                (batch.entireDebtWithoutRedistribution + trove.redistBoldDebtGain) * batch.annualInterestRate;
            change.oldWeightedRecordedBatchManagementFee = batch.weightedRecordedBatchManagementFee;
            change.newWeightedRecordedBatchManagementFee =
                (batch.entireDebtWithoutRedistribution + trove.redistBoldDebtGain) * batch.annualManagementFee;
        }

        troveManagerCached.onApplyTroveInterest(
            _troveId,
            trove.entireColl,
            trove.entireDebt,
            batchManager,
            batch.entireCollWithoutRedistribution,
            batch.entireDebtWithoutRedistribution,
            change
        );
        activePool.mintAggInterestAndAccountForTroveChange(change, batchManager);

        // If the trove was zombie, and now it’s not anymore, put it back in the list
        if (_checkTroveIsZombie(troveManagerCached, _troveId) && trove.entireDebt >= MIN_DEBT) {
            troveManagerCached.setTroveStatusToActive(_troveId);
            _reInsertIntoSortedTroves(
                _troveId, trove.annualInterestRate, _upperHint, _lowerHint, batchManager, batch.annualInterestRate
            );
        }
    }

    function getInterestIndividualDelegateOf(uint256 _troveId)
        external
        view
        returns (InterestIndividualDelegate memory)
    {
        return interestIndividualDelegateOf[_troveId];
    }

    function setInterestIndividualDelegate(
        uint256 _troveId,
        address _delegate,
        uint128 _minInterestRate,
        uint128 _maxInterestRate,
        // only needed if trove was previously in a batch:
        uint256 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee,
        uint256 _minInterestRateChangePeriod
    ) external {
        _requireIsNotShutDown();
        _requireTroveIsActive(troveManager, _troveId);
        _requireCallerIsBorrower(_troveId);
        _requireValidAnnualInterestRate(_minInterestRate);
        _requireValidAnnualInterestRate(_maxInterestRate);
        // With the check below, it could only be ==
        _requireOrderedRange(_minInterestRate, _maxInterestRate);

        interestIndividualDelegateOf[_troveId] =
            InterestIndividualDelegate(_delegate, _minInterestRate, _maxInterestRate, _minInterestRateChangePeriod);
        // Can’t have both individual delegation and batch manager
        if (interestBatchManagerOf[_troveId] != address(0)) {
            // Not needed, implicitly checked in removeFromBatch
            //_requireValidAnnualInterestRate(_newAnnualInterestRate);
            removeFromBatch(_troveId, _newAnnualInterestRate, _upperHint, _lowerHint, _maxUpfrontFee);
        }
    }

    function removeInterestIndividualDelegate(uint256 _troveId) external {
        _requireCallerIsBorrower(_troveId);
        delete interestIndividualDelegateOf[_troveId];
    }

    function getInterestBatchManager(address _account) external view returns (InterestBatchManager memory) {
        return interestBatchManagers[_account];
    }

    function registerBatchManager(
        uint128 _minInterestRate,
        uint128 _maxInterestRate,
        uint128 _currentInterestRate,
        uint128 _annualManagementFee,
        uint128 _minInterestRateChangePeriod
    ) external {
        _requireIsNotShutDown();
        _requireNonExistentInterestBatchManager(msg.sender);
        _requireValidAnnualInterestRate(_minInterestRate);
        _requireValidAnnualInterestRate(_maxInterestRate);
        // With the check below, it could only be ==
        _requireOrderedRange(_minInterestRate, _maxInterestRate);
        _requireInterestRateInRange(_currentInterestRate, _minInterestRate, _maxInterestRate);
        // Not needed, implicitly checked in the condition above:
        //_requireValidAnnualInterestRate(_currentInterestRate);
        if (_annualManagementFee > MAX_ANNUAL_BATCH_MANAGEMENT_FEE) revert AnnualManagementFeeTooHigh();
        if (_minInterestRateChangePeriod < MIN_INTEREST_RATE_CHANGE_PERIOD) revert MinInterestRateChangePeriodTooLow();

        interestBatchManagers[msg.sender] =
            InterestBatchManager(_minInterestRate, _maxInterestRate, _minInterestRateChangePeriod);

        troveManager.onRegisterBatchManager(msg.sender, _currentInterestRate, _annualManagementFee);
    }

    function lowerBatchManagementFee(uint256 _newAnnualManagementFee) external {
        _requireIsNotShutDown();
        _requireValidInterestBatchManager(msg.sender);

        ITroveManager troveManagerCached = troveManager;

        LatestBatchData memory batch = troveManagerCached.getLatestBatchData(msg.sender);
        if (_newAnnualManagementFee >= batch.annualManagementFee) {
            revert NewFeeNotLower();
        }

        // Lower batch fee on TM
        troveManagerCached.onLowerBatchManagerAnnualFee(
            msg.sender,
            batch.entireCollWithoutRedistribution,
            batch.entireDebtWithoutRedistribution,
            _newAnnualManagementFee
        );

        // active pool mint
        TroveChange memory batchChange;
        batchChange.batchAccruedManagementFee = batch.accruedManagementFee;
        batchChange.oldWeightedRecordedDebt = batch.weightedRecordedDebt;
        batchChange.newWeightedRecordedDebt = batch.entireDebtWithoutRedistribution * batch.annualInterestRate;
        batchChange.oldWeightedRecordedBatchManagementFee = batch.weightedRecordedBatchManagementFee;
        batchChange.newWeightedRecordedBatchManagementFee =
            batch.entireDebtWithoutRedistribution * _newAnnualManagementFee;

        activePool.mintAggInterestAndAccountForTroveChange(batchChange, msg.sender);
    }

    function setBatchManagerAnnualInterestRate(
        uint128 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external {
        _requireIsNotShutDown();
        _requireValidInterestBatchManager(msg.sender);
        _requireInterestRateInBatchManagerRange(msg.sender, _newAnnualInterestRate);
        // Not needed, implicitly checked in the condition above:
        //_requireValidAnnualInterestRate(_newAnnualInterestRate);

        ITroveManager troveManagerCached = troveManager;
        IActivePool activePoolCached = activePool;

        LatestBatchData memory batch = troveManagerCached.getLatestBatchData(msg.sender);
        _requireBatchInterestRateChangePeriodPassed(msg.sender, uint256(batch.lastInterestRateAdjTime));

        uint256 newDebt = batch.entireDebtWithoutRedistribution;

        TroveChange memory batchChange;
        batchChange.batchAccruedManagementFee = batch.accruedManagementFee;
        batchChange.oldWeightedRecordedDebt = batch.weightedRecordedDebt;
        batchChange.newWeightedRecordedDebt = newDebt * _newAnnualInterestRate;
        batchChange.oldWeightedRecordedBatchManagementFee = batch.weightedRecordedBatchManagementFee;
        batchChange.newWeightedRecordedBatchManagementFee = newDebt * batch.annualManagementFee;

        // Apply upfront fee on premature adjustments
        if (
            batch.annualInterestRate != _newAnnualInterestRate
                && block.timestamp < batch.lastInterestRateAdjTime + INTEREST_RATE_ADJ_COOLDOWN
        ) {
            uint256 price = _requireOraclesLive();

            uint256 avgInterestRate = activePoolCached.getNewApproxAvgInterestRateFromTroveChange(batchChange);
            batchChange.upfrontFee = _calcUpfrontFee(newDebt, avgInterestRate);
            _requireUserAcceptsUpfrontFee(batchChange.upfrontFee, _maxUpfrontFee);

            newDebt += batchChange.upfrontFee;

            // Recalculate the batch's weighted terms, now taking into account the upfront fee
            batchChange.newWeightedRecordedDebt = newDebt * _newAnnualInterestRate;
            batchChange.newWeightedRecordedBatchManagementFee = newDebt * batch.annualManagementFee;

            // Disallow a premature adjustment if it would result in TCR < CCR
            // (which includes the case when TCR is already below CCR before the adjustment).
            uint256 newTCR = _getNewTCRFromTroveChange(batchChange, price);
            _requireNewTCRisAboveCCR(newTCR);
        }

        activePoolCached.mintAggInterestAndAccountForTroveChange(batchChange, msg.sender);

        // Check batch is not empty, and then reinsert in sorted list
        if (!sortedTroves.isEmptyBatch(BatchId.wrap(msg.sender))) {
            sortedTroves.reInsertBatch(BatchId.wrap(msg.sender), _newAnnualInterestRate, _upperHint, _lowerHint);
        }

        troveManagerCached.onSetBatchManagerAnnualInterestRate(
            msg.sender, batch.entireCollWithoutRedistribution, newDebt, _newAnnualInterestRate, batchChange.upfrontFee
        );
    }

    function setInterestBatchManager(
        uint256 _troveId,
        address _newBatchManager,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) public override {
        _requireIsNotShutDown();
        LocalVariables_setInterestBatchManager memory vars;
        vars.troveManager = troveManager;
        vars.activePool = activePool;
        vars.sortedTroves = sortedTroves;

        _requireTroveIsActive(vars.troveManager, _troveId);
        _requireCallerIsBorrower(_troveId);
        _requireValidInterestBatchManager(_newBatchManager);
        _requireIsNotInBatch(_troveId);

        interestBatchManagerOf[_troveId] = _newBatchManager;
        // Can’t have both individual delegation and batch manager
        if (interestIndividualDelegateOf[_troveId].account != address(0)) delete interestIndividualDelegateOf[_troveId];

        vars.trove = vars.troveManager.getLatestTroveData(_troveId);
        vars.newBatch = vars.troveManager.getLatestBatchData(_newBatchManager);

        TroveChange memory newBatchTroveChange;
        newBatchTroveChange.appliedRedistBoldDebtGain = vars.trove.redistBoldDebtGain;
        newBatchTroveChange.appliedRedistCollGain = vars.trove.redistCollGain;
        newBatchTroveChange.batchAccruedManagementFee = vars.newBatch.accruedManagementFee;
        newBatchTroveChange.oldWeightedRecordedDebt =
            vars.newBatch.weightedRecordedDebt + vars.trove.weightedRecordedDebt;
        newBatchTroveChange.newWeightedRecordedDebt =
            (vars.newBatch.entireDebtWithoutRedistribution + vars.trove.entireDebt) * vars.newBatch.annualInterestRate;

        // An upfront fee is always charged upon joining a batch to ensure that borrowers can not game the fee logic
        // and gain free interest rate updates (e.g. if they also manage the batch they joined)
        vars.trove.entireDebt =
            _applyUpfrontFee(vars.trove.entireColl, vars.trove.entireDebt, newBatchTroveChange, _maxUpfrontFee);

        // Recalculate newWeightedRecordedDebt, now taking into account the upfront fee
        newBatchTroveChange.newWeightedRecordedDebt =
            (vars.newBatch.entireDebtWithoutRedistribution + vars.trove.entireDebt) * vars.newBatch.annualInterestRate;

        // Add batch fees
        newBatchTroveChange.oldWeightedRecordedBatchManagementFee = vars.newBatch.weightedRecordedBatchManagementFee;
        newBatchTroveChange.newWeightedRecordedBatchManagementFee =
            (vars.newBatch.entireDebtWithoutRedistribution + vars.trove.entireDebt) * vars.newBatch.annualManagementFee;
        vars.activePool.mintAggInterestAndAccountForTroveChange(newBatchTroveChange, _newBatchManager);

        vars.troveManager.onSetInterestBatchManager(
            ITroveManager.OnSetInterestBatchManagerParams({
                troveId: _troveId,
                troveColl: vars.trove.entireColl,
                troveDebt: vars.trove.entireDebt,
                troveChange: newBatchTroveChange,
                newBatchAddress: _newBatchManager,
                newBatchColl: vars.newBatch.entireCollWithoutRedistribution,
                newBatchDebt: vars.newBatch.entireDebtWithoutRedistribution
            })
        );

        vars.sortedTroves.remove(_troveId);
        vars.sortedTroves.insertIntoBatch(
            _troveId, BatchId.wrap(_newBatchManager), vars.newBatch.annualInterestRate, _upperHint, _lowerHint
        );
    }

    function removeFromBatch(
        uint256 _troveId,
        uint256 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) public override {
        _requireIsNotShutDown();

        LocalVariables_removeFromBatch memory vars;
        vars.troveManager = troveManager;
        vars.sortedTroves = sortedTroves;

        _requireTroveIsActive(vars.troveManager, _troveId);
        _requireCallerIsBorrower(_troveId);
        _requireValidAnnualInterestRate(_newAnnualInterestRate);

        vars.batchManager = _requireIsInBatch(_troveId);
        delete interestBatchManagerOf[_troveId];

        // Remove trove from Batch in SortedTroves
        vars.sortedTroves.removeFromBatch(_troveId);
        // Reinsert as single trove
        vars.sortedTroves.insert(_troveId, _newAnnualInterestRate, _upperHint, _lowerHint);

        vars.trove = vars.troveManager.getLatestTroveData(_troveId);
        vars.batch = vars.troveManager.getLatestBatchData(vars.batchManager);

        uint256 batchFutureDebt =
            vars.batch.entireDebtWithoutRedistribution - (vars.trove.entireDebt - vars.trove.redistBoldDebtGain);

        TroveChange memory batchChange;
        batchChange.appliedRedistBoldDebtGain = vars.trove.redistBoldDebtGain;
        batchChange.appliedRedistCollGain = vars.trove.redistCollGain;
        batchChange.batchAccruedManagementFee = vars.batch.accruedManagementFee;
        batchChange.oldWeightedRecordedDebt = vars.batch.weightedRecordedDebt;
        batchChange.newWeightedRecordedDebt =
            batchFutureDebt * vars.batch.annualInterestRate + vars.trove.entireDebt * _newAnnualInterestRate;

        // Apply upfront fee on premature adjustments
        if (
            vars.batch.annualInterestRate != _newAnnualInterestRate
                && block.timestamp < vars.trove.lastInterestRateAdjTime + INTEREST_RATE_ADJ_COOLDOWN
        ) {
            vars.trove.entireDebt =
                _applyUpfrontFee(vars.trove.entireColl, vars.trove.entireDebt, batchChange, _maxUpfrontFee);
        }

        // Recalculate newWeightedRecordedDebt, now taking into account the upfront fee
        batchChange.newWeightedRecordedDebt =
            batchFutureDebt * vars.batch.annualInterestRate + vars.trove.entireDebt * _newAnnualInterestRate;
        // Add batch fees
        batchChange.oldWeightedRecordedBatchManagementFee = vars.batch.weightedRecordedBatchManagementFee;
        batchChange.newWeightedRecordedBatchManagementFee = batchFutureDebt * vars.batch.annualManagementFee;

        activePool.mintAggInterestAndAccountForTroveChange(batchChange, vars.batchManager);

        vars.troveManager.onRemoveFromBatch(
            _troveId,
            vars.trove.entireColl,
            vars.trove.entireDebt,
            batchChange,
            vars.batchManager,
            vars.batch.entireCollWithoutRedistribution,
            vars.batch.entireDebtWithoutRedistribution,
            _newAnnualInterestRate
        );
    }

    function switchBatchManager(
        uint256 _troveId,
        uint256 _removeUpperHint,
        uint256 _removeLowerHint,
        address _newBatchManager,
        uint256 _addUpperHint,
        uint256 _addLowerHint,
        uint256 _maxUpfrontFee
    ) external override {
        address oldBatchManager = _requireIsInBatch(_troveId);
        _requireNewInterestBatchManager(oldBatchManager, _newBatchManager);

        LatestBatchData memory oldBatch = troveManager.getLatestBatchData(oldBatchManager);

        removeFromBatch(_troveId, oldBatch.annualInterestRate, _removeUpperHint, _removeLowerHint, 0);
        setInterestBatchManager(_troveId, _newBatchManager, _addUpperHint, _addLowerHint, _maxUpfrontFee);
    }

    function _applyUpfrontFee(
        uint256 _troveEntireColl,
        uint256 _troveEntireDebt,
        TroveChange memory _troveChange,
        uint256 _maxUpfrontFee
    ) internal returns (uint256) {
        uint256 price = _requireOraclesLive();

        uint256 avgInterestRate = activePool.getNewApproxAvgInterestRateFromTroveChange(_troveChange);
        _troveChange.upfrontFee = _calcUpfrontFee(_troveEntireDebt, avgInterestRate);
        _requireUserAcceptsUpfrontFee(_troveChange.upfrontFee, _maxUpfrontFee);

        _troveEntireDebt += _troveChange.upfrontFee;

        // ICR is based on the requested Bold amount + upfront fee.
        uint256 newICR = LiquityMath._computeCR(_troveEntireColl, _troveEntireDebt, price);
        _requireICRisAboveMCR(newICR);

        // Disallow a premature adjustment if it would result in TCR < CCR
        // (which includes the case when TCR is already below CCR before the adjustment).
        uint256 newTCR = _getNewTCRFromTroveChange(_troveChange, price);
        _requireNewTCRisAboveCCR(newTCR);

        return _troveEntireDebt;
    }

    function _calcUpfrontFee(uint256 _debt, uint256 _avgInterestRate) internal pure returns (uint256) {
        return _calcInterest(_debt * _avgInterestRate, UPFRONT_INTEREST_PERIOD);
    }

    // Call from TM to clean state here
    function onLiquidateTrove(uint256 _troveId) external {
        _requireCallerIsTroveManager();

        _wipeTroveMappings(_troveId);
    }

    function _wipeTroveMappings(uint256 _troveId) internal {
        delete interestIndividualDelegateOf[_troveId];
        delete interestBatchManagerOf[_troveId];
        _wipeAddRemoveManagers(_troveId);
    }

    /**
     * Claim remaining collateral from a liquidation with ICR exceeding the liquidation penalty
     */
    function claimCollateral() external override {
        // send coll from CollSurplus Pool to owner
        collSurplusPool.claimColl(msg.sender);
    }

    function shutdown() external {
        if (hasBeenShutDown) revert IsShutDown();

        uint256 totalColl = getEntireSystemColl();
        uint256 totalDebt = getEntireSystemDebt();
        (uint256 price, bool newOracleFailureDetected) = priceFeed.fetchPrice();
        // If the oracle failed, the above call to PriceFeed will have shut this branch down
        if (newOracleFailureDetected) return;

        // Otherwise, proceed with the TCR check:
        uint256 TCR = LiquityMath._computeCR(totalColl, totalDebt, price);
        if (TCR >= SCR) revert TCRNotBelowSCR();

        _applyShutdown();

        emit ShutDown(TCR);
    }

    // Not technically a "Borrower op", but seems best placed here given current shutdown logic.
    function shutdownFromOracleFailure() external {
        _requireCallerIsPriceFeed();

        // No-op rather than revert here, so that the outer function call which fetches the price does not revert
        // if the system is already shut down.
        if (hasBeenShutDown) return;

        _applyShutdown();
    }

    function _applyShutdown() internal {
        activePool.mintAggInterest();
        hasBeenShutDown = true;
        troveManager.shutdown();
    }

    // --- Helper functions ---

    function _reInsertIntoSortedTroves(
        uint256 _troveId,
        uint256 _troveAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        address _batchManager,
        uint256 _batchAnnualInterestRate
    ) internal {
        // If it was in a batch, we need to put it back, otherwise we insert it normally
        if (_batchManager == address(0)) {
            sortedTroves.insert(_troveId, _troveAnnualInterestRate, _upperHint, _lowerHint);
        } else {
            sortedTroves.insertIntoBatch(
                _troveId, BatchId.wrap(_batchManager), _batchAnnualInterestRate, _upperHint, _lowerHint
            );
        }
    }

    // This function mints the BOLD corresponding to the borrower's chosen debt increase
    // (it does not mint the accrued interest).
    function _moveTokensFromAdjustment(
        address withdrawalReceiver,
        TroveChange memory _troveChange,
        IBoldToken _boldToken,
        IActivePool _activePool
    ) internal {
        if (_troveChange.debtIncrease > 0) {
            _boldToken.mint(withdrawalReceiver, _troveChange.debtIncrease);
        } else if (_troveChange.debtDecrease > 0) {
            _boldToken.burn(msg.sender, _troveChange.debtDecrease);
        }

        if (_troveChange.collIncrease > 0) {
            // Pull coll tokens from sender and move them to the Active Pool
            _pullCollAndSendToActivePool(_activePool, _troveChange.collIncrease);
        } else if (_troveChange.collDecrease > 0) {
            // Pull Coll from Active Pool and decrease its recorded Coll balance
            _activePool.sendColl(withdrawalReceiver, _troveChange.collDecrease);
        }
    }

    function _pullCollAndSendToActivePool(IActivePool _activePool, uint256 _amount) internal {
        // Send Coll tokens from sender to active pool
        collToken.safeTransferFrom(msg.sender, address(_activePool), _amount);
        // Make sure Active Pool accountancy is right
        _activePool.accountForReceivedColl(_amount);
    }

    function checkBatchManagerExists(address _batchManager) external view returns (bool) {
        return interestBatchManagers[_batchManager].maxInterestRate > 0;
    }

    // --- 'Require' wrapper functions ---

    function _requireIsNotShutDown() internal view {
        if (hasBeenShutDown) {
            revert IsShutDown();
        }
    }

    function _requireNonZeroAdjustment(TroveChange memory _troveChange) internal pure {
        if (
            _troveChange.collIncrease == 0 && _troveChange.collDecrease == 0 && _troveChange.debtIncrease == 0
                && _troveChange.debtDecrease == 0
        ) {
            revert ZeroAdjustment();
        }
    }

    function _requireSenderIsOwnerOrInterestManager(uint256 _troveId) internal view {
        address owner = troveNFT.ownerOf(_troveId);
        if (msg.sender != owner && msg.sender != interestIndividualDelegateOf[_troveId].account) {
            revert NotOwnerNorInterestManager();
        }
    }

    function _requireValidDelegateAdustment(
        uint256 _troveId,
        uint256 _lastInterestRateAdjTime,
        uint256 _annualInterestRate
    ) internal view {
        InterestIndividualDelegate memory individualDelegate = interestIndividualDelegateOf[_troveId];
        // We have previously checked that sender is either owner or delegate
        // If it’s owner, this restriction doesn’t apply
        if (individualDelegate.account == msg.sender) {
            _requireInterestRateInRange(
                _annualInterestRate, individualDelegate.minInterestRate, individualDelegate.maxInterestRate
            );
            _requireDelegateInterestRateChangePeriodPassed(
                _lastInterestRateAdjTime, individualDelegate.minInterestRateChangePeriod
            );
        }
    }

    function _requireIsNotInBatch(uint256 _troveId) internal view {
        if (interestBatchManagerOf[_troveId] != address(0)) {
            revert TroveInBatch();
        }
    }

    function _requireIsInBatch(uint256 _troveId) internal view returns (address) {
        address batchManager = interestBatchManagerOf[_troveId];
        if (batchManager == address(0)) {
            revert TroveNotInBatch();
        }

        return batchManager;
    }

    function _requireTroveDoesNotExists(ITroveManager _troveManager, uint256 _troveId) internal view {
        ITroveManager.Status status = _troveManager.getTroveStatus(_troveId);
        if (status != ITroveManager.Status.nonExistent) {
            revert TroveExists();
        }
    }

    function _requireTroveIsOpen(ITroveManager _troveManager, uint256 _troveId) internal view {
        ITroveManager.Status status = _troveManager.getTroveStatus(_troveId);
        if (status != ITroveManager.Status.active && status != ITroveManager.Status.zombie) {
            revert TroveNotOpen();
        }
    }

    function _requireTroveIsActive(ITroveManager _troveManager, uint256 _troveId) internal view {
        ITroveManager.Status status = _troveManager.getTroveStatus(_troveId);
        if (status != ITroveManager.Status.active) {
            revert TroveNotActive();
        }
    }

    function _requireTroveIsZombie(ITroveManager _troveManager, uint256 _troveId) internal view {
        if (!_checkTroveIsZombie(_troveManager, _troveId)) {
            revert TroveNotZombie();
        }
    }

    function _checkTroveIsZombie(ITroveManager _troveManager, uint256 _troveId) internal view returns (bool) {
        ITroveManager.Status status = _troveManager.getTroveStatus(_troveId);
        return status == ITroveManager.Status.zombie;
    }

    function _requireNonZeroDebt(uint256 _troveDebt) internal pure {
        if (_troveDebt == 0) {
            revert TroveWithZeroDebt();
        }
    }

    function _requireUserAcceptsUpfrontFee(uint256 _fee, uint256 _maxFee) internal pure {
        if (_fee > _maxFee) {
            revert UpfrontFeeTooHigh();
        }
    }

    function _requireValidAdjustmentInCurrentMode(
        TroveChange memory _troveChange,
        LocalVariables_adjustTrove memory _vars
    ) internal view {
        /*
        * Below Critical Threshold, it is not permitted:
        *
        * - Borrowing, unless it brings TCR up to CCR again
        * - Collateral withdrawal except accompanied by a debt repayment of at least the same value
        *
        * In Normal Mode, ensure:
        *
        * - The adjustment won't pull the TCR below CCR
        *
        * In Both cases:
        * - The new ICR is above MCR
        */
        _requireICRisAboveMCR(_vars.newICR);

        uint256 newTCR = _getNewTCRFromTroveChange(_troveChange, _vars.price);
        if (_vars.isBelowCriticalThreshold) {
            _requireNoBorrowingUnlessNewTCRisAboveCCR(_troveChange.debtIncrease, newTCR);
            _requireDebtRepaymentGeCollWithdrawal(_troveChange, _vars.price);
        } else {
            // if Normal Mode
            _requireNewTCRisAboveCCR(newTCR);
        }
    }

    function _requireICRisAboveMCR(uint256 _newICR) internal view {
        if (_newICR < MCR) {
            revert ICRBelowMCR();
        }
    }

    function _requireNoBorrowingUnlessNewTCRisAboveCCR(uint256 _debtIncrease, uint256 _newTCR) internal view {
        if (_debtIncrease > 0 && _newTCR < CCR) {
            revert TCRBelowCCR();
        }
    }

    function _requireDebtRepaymentGeCollWithdrawal(TroveChange memory _troveChange, uint256 _price) internal pure {
        if ((_troveChange.debtDecrease * DECIMAL_PRECISION < _troveChange.collDecrease * _price)) {
            revert RepaymentNotMatchingCollWithdrawal();
        }
    }

    function _requireNewTCRisAboveCCR(uint256 _newTCR) internal view {
        if (_newTCR < CCR) {
            revert TCRBelowCCR();
        }
    }

    function _requireAtLeastMinDebt(uint256 _debt) internal pure {
        if (_debt < MIN_DEBT) {
            revert DebtBelowMin();
        }
    }

    function _requireValidCollWithdrawal(uint256 _currentColl, uint256 _collWithdrawal) internal pure {
        if (_collWithdrawal > _currentColl) {
            revert CollWithdrawalTooHigh();
        }
    }

    function _requireSufficientBoldBalance(IBoldToken _boldToken, address _borrower, uint256 _debtRepayment)
        internal
        view
    {
        if (_boldToken.balanceOf(_borrower) < _debtRepayment) {
            revert NotEnoughBoldBalance();
        }
    }

    function _requireValidAnnualInterestRate(uint256 _annualInterestRate) internal pure {
        if (_annualInterestRate < MIN_ANNUAL_INTEREST_RATE) {
            revert InterestRateTooLow();
        }
        if (_annualInterestRate > MAX_ANNUAL_INTEREST_RATE) {
            revert InterestRateTooHigh();
        }
    }

    function _requireAnnualInterestRateIsNew(uint256 _oldAnnualInterestRate, uint256 _newAnnualInterestRate)
        internal
        pure
    {
        if (_oldAnnualInterestRate == _newAnnualInterestRate) {
            revert InterestRateNotNew();
        }
    }

    function _requireOrderedRange(uint256 _minInterestRate, uint256 _maxInterestRate) internal pure {
        if (_minInterestRate >= _maxInterestRate) revert MinGeMax();
    }

    function _requireInterestRateInBatchManagerRange(address _interestBatchManagerAddress, uint256 _annualInterestRate)
        internal
        view
    {
        InterestBatchManager memory interestBatchManager = interestBatchManagers[_interestBatchManagerAddress];
        _requireInterestRateInRange(
            _annualInterestRate, interestBatchManager.minInterestRate, interestBatchManager.maxInterestRate
        );
    }

    function _requireInterestRateInRange(
        uint256 _annualInterestRate,
        uint256 _minInterestRate,
        uint256 _maxInterestRate
    ) internal pure {
        if (_minInterestRate > _annualInterestRate || _annualInterestRate > _maxInterestRate) {
            revert InterestNotInRange();
        }
    }

    function _requireBatchInterestRateChangePeriodPassed(
        address _interestBatchManagerAddress,
        uint256 _lastInterestRateAdjTime
    ) internal view {
        InterestBatchManager memory interestBatchManager = interestBatchManagers[_interestBatchManagerAddress];
        if (block.timestamp < _lastInterestRateAdjTime + uint256(interestBatchManager.minInterestRateChangePeriod)) {
            revert BatchInterestRateChangePeriodNotPassed();
        }
    }

    function _requireDelegateInterestRateChangePeriodPassed(
        uint256 _lastInterestRateAdjTime,
        uint256 _minInterestRateChangePeriod
    ) internal view {
        if (block.timestamp < _lastInterestRateAdjTime + _minInterestRateChangePeriod) {
            revert DelegateInterestRateChangePeriodNotPassed();
        }
    }

    function _requireValidInterestBatchManager(address _interestBatchManagerAddress) internal view {
        if (interestBatchManagers[_interestBatchManagerAddress].maxInterestRate == 0) {
            revert InvalidInterestBatchManager();
        }
    }

    function _requireNonExistentInterestBatchManager(address _interestBatchManagerAddress) internal view {
        if (interestBatchManagers[_interestBatchManagerAddress].maxInterestRate > 0) {
            revert BatchManagerExists();
        }
    }

    function _requireNewInterestBatchManager(address _oldBatchManagerAddress, address _newBatchManagerAddress)
        internal
        pure
    {
        if (_oldBatchManagerAddress == _newBatchManagerAddress) {
            revert BatchManagerNotNew();
        }
    }

    function _requireCallerIsTroveManager() internal view {
        if (msg.sender != address(troveManager)) {
            revert CallerNotTroveManager();
        }
    }

    function _requireCallerIsPriceFeed() internal view {
        if (msg.sender != address(priceFeed)) {
            revert CallerNotPriceFeed();
        }
    }

    function _requireOraclesLive() internal returns (uint256) {
        (uint256 price, bool newOracleFailureDetected) = priceFeed.fetchPrice();
        if (newOracleFailureDetected) {
            revert NewOracleFailureDetected();
        }

        return price;
    }

    // --- ICR and TCR getters ---

    function _getNewTCRFromTroveChange(TroveChange memory _troveChange, uint256 _price)
        internal
        view
        returns (uint256 newTCR)
    {
        uint256 totalColl = getEntireSystemColl();
        totalColl += _troveChange.collIncrease;
        totalColl -= _troveChange.collDecrease;

        uint256 totalDebt = getEntireSystemDebt();
        totalDebt += _troveChange.debtIncrease;
        totalDebt += _troveChange.upfrontFee;
        totalDebt -= _troveChange.debtDecrease;

        newTCR = LiquityMath._computeCR(totalColl, totalDebt, _price);
    }
}

// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.24;

address constant ZERO_ADDRESS = address(0);

uint256 constant MAX_UINT256 = type(uint256).max;

uint256 constant DECIMAL_PRECISION = 1e18;
uint256 constant _100pct = DECIMAL_PRECISION;
uint256 constant _1pct = DECIMAL_PRECISION / 100;

// Amount of ETH to be locked in gas pool on opening troves
uint256 constant ETH_GAS_COMPENSATION = 0.0375 ether;

// Liquidation
uint256 constant MIN_LIQUIDATION_PENALTY_SP = 5e16; // 5%
uint256 constant MAX_LIQUIDATION_PENALTY_REDISTRIBUTION = 20e16; // 20%

// Fraction of collateral awarded to liquidator
uint256 constant COLL_GAS_COMPENSATION_DIVISOR = 200; // dividing by 200 yields 0.5%
uint256 constant COLL_GAS_COMPENSATION_CAP = 2 ether; // Max coll gas compensation capped at 2 ETH

// Minimum amount of net Bold debt a trove must have
uint256 constant MIN_DEBT = 2000e18;

uint256 constant MIN_ANNUAL_INTEREST_RATE = _1pct / 2; // 0.5%
uint256 constant MAX_ANNUAL_INTEREST_RATE = 250 * _1pct;

// Batch management params
uint128 constant MAX_ANNUAL_BATCH_MANAGEMENT_FEE = uint128(_100pct / 10); // 10%
uint128 constant MIN_INTEREST_RATE_CHANGE_PERIOD = 1 hours; // only applies to batch managers / batched Troves

uint256 constant REDEMPTION_FEE_FLOOR = _1pct / 2; // 0.5%

// For the debt / shares ratio to increase by a factor 1e9
// at a average annual debt increase (compounded interest + fees) of 10%, it would take more than 217 years (log(1e9)/log(1.1))
// at a average annual debt increase (compounded interest + fees) of 50%, it would take more than 51 years (log(1e9)/log(1.5))
// The increase pace could be forced to be higher through an inflation attack,
// but precisely the fact that we have this max value now prevents the attack
uint256 constant MAX_BATCH_SHARES_RATIO = 1e9;

// Half-life of 6h. 6h = 360 min
// (1/2) = d^360 => d = (1/2)^(1/360)
uint256 constant REDEMPTION_MINUTE_DECAY_FACTOR = 998076443575628800;

// BETA: 18 digit decimal. Parameter by which to divide the redeemed fraction, in order to calc the new base rate from a redemption.
// Corresponds to (1 / ALPHA) in the white paper.
uint256 constant REDEMPTION_BETA = 1;

// To prevent redemptions unless Bold depegs below 0.95 and allow the system to take off
uint256 constant INITIAL_BASE_RATE = _100pct; // 100% initial redemption rate

// Discount to be used once the shutdown thas been triggered
uint256 constant URGENT_REDEMPTION_BONUS = 2e16; // 2%

uint256 constant ONE_MINUTE = 1 minutes;
uint256 constant ONE_YEAR = 365 days;
uint256 constant UPFRONT_INTEREST_PERIOD = 7 days;
uint256 constant INTEREST_RATE_ADJ_COOLDOWN = 7 days;

uint256 constant SP_YIELD_SPLIT = 75 * _1pct; // 75%

// Dummy contract that lets legacy Hardhat tests query some of the constants
contract Constants {
    uint256 public constant _ETH_GAS_COMPENSATION = ETH_GAS_COMPENSATION;
    uint256 public constant _MIN_DEBT = MIN_DEBT;
}

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

import "lib/Solady/src/utils/SSTORE2.sol";

contract FixedAssetReader {
    struct Asset {
        uint128 start;
        uint128 end;
    }

    address public immutable pointer;

    mapping(bytes4 => Asset) public assets;

    function readAsset(bytes4 _sig) public view returns (string memory) {
        return string(SSTORE2.read(pointer, uint256(assets[_sig].start), uint256(assets[_sig].end)));
    }

    constructor(address _pointer, bytes4[] memory _sigs, Asset[] memory _assets) {
        pointer = _pointer;
        require(_sigs.length == _assets.length, "FixedAssetReader: Invalid input");
        for (uint256 i = 0; i < _sigs.length; i++) {
            assets[_sigs[i]] = _assets[i];
        }
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IInterestRouter.sol";
import "./IBoldRewardsReceiver.sol";
import "../Types/TroveChange.sol";

interface IActivePool {
    function defaultPoolAddress() external view returns (address);
    function borrowerOperationsAddress() external view returns (address);
    function troveManagerAddress() external view returns (address);
    function interestRouter() external view returns (IInterestRouter);
    // We avoid IStabilityPool here in order to prevent creating a dependency cycle that would break flattening
    function stabilityPool() external view returns (IBoldRewardsReceiver);

    function getCollBalance() external view returns (uint256);
    function getBoldDebt() external view returns (uint256);
    function lastAggUpdateTime() external view returns (uint256);
    function aggRecordedDebt() external view returns (uint256);
    function aggWeightedDebtSum() external view returns (uint256);
    function aggBatchManagementFees() external view returns (uint256);
    function aggWeightedBatchManagementFeeSum() external view returns (uint256);
    function calcPendingAggInterest() external view returns (uint256);
    function calcPendingSPYield() external view returns (uint256);
    function calcPendingAggBatchManagementFee() external view returns (uint256);
    function getNewApproxAvgInterestRateFromTroveChange(TroveChange calldata _troveChange)
        external
        view
        returns (uint256);

    function mintAggInterest() external;
    function mintAggInterestAndAccountForTroveChange(TroveChange calldata _troveChange, address _batchManager)
        external;
    function mintBatchManagementFeeAndAccountForChange(TroveChange calldata _troveChange, address _batchAddress)
        external;

    function setShutdownFlag() external;
    function hasBeenShutDown() external view returns (bool);
    function shutdownTime() external view returns (uint256);

    function sendColl(address _account, uint256 _amount) external;
    function sendCollToDefaultPool(uint256 _amount) external;
    function receiveColl(uint256 _amount) external;
    function accountForReceivedColl(uint256 _amount) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IAddRemoveManagers {
    function setAddManager(uint256 _troveId, address _manager) external;
    function setRemoveManager(uint256 _troveId, address _manager) external;
    function setRemoveManagerWithReceiver(uint256 _troveId, address _manager, address _receiver) external;
    function addManagerOf(uint256 _troveId) external view returns (address);
    function removeManagerReceiverOf(uint256 _troveId) external view returns (address, address);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IActivePool.sol";
import "./IBoldToken.sol";
import "./IBorrowerOperations.sol";
import "./ICollSurplusPool.sol";
import "./IDefaultPool.sol";
import "./IHintHelpers.sol";
import "./IMultiTroveGetter.sol";
import "./ISortedTroves.sol";
import "./IStabilityPool.sol";
import "./ITroveManager.sol";
import "./ITroveNFT.sol";
import {IMetadataNFT} from "../NFTMetadata/MetadataNFT.sol";
import "./ICollateralRegistry.sol";
import "./IInterestRouter.sol";
import "./IPriceFeed.sol";

interface IAddressesRegistry {
    struct AddressVars {
        IERC20Metadata collToken;
        IBorrowerOperations borrowerOperations;
        ITroveManager troveManager;
        ITroveNFT troveNFT;
        IMetadataNFT metadataNFT;
        IStabilityPool stabilityPool;
        IPriceFeed priceFeed;
        IActivePool activePool;
        IDefaultPool defaultPool;
        address gasPoolAddress;
        ICollSurplusPool collSurplusPool;
        ISortedTroves sortedTroves;
        IInterestRouter interestRouter;
        IHintHelpers hintHelpers;
        IMultiTroveGetter multiTroveGetter;
        ICollateralRegistry collateralRegistry;
        IBoldToken boldToken;
        IWETH WETH;
    }

    function CCR() external returns (uint256);
    function SCR() external returns (uint256);
    function MCR() external returns (uint256);
    function LIQUIDATION_PENALTY_SP() external returns (uint256);
    function LIQUIDATION_PENALTY_REDISTRIBUTION() external returns (uint256);

    function collToken() external view returns (IERC20Metadata);
    function borrowerOperations() external view returns (IBorrowerOperations);
    function troveManager() external view returns (ITroveManager);
    function troveNFT() external view returns (ITroveNFT);
    function metadataNFT() external view returns (IMetadataNFT);
    function stabilityPool() external view returns (IStabilityPool);
    function priceFeed() external view returns (IPriceFeed);
    function activePool() external view returns (IActivePool);
    function defaultPool() external view returns (IDefaultPool);
    function gasPoolAddress() external view returns (address);
    function collSurplusPool() external view returns (ICollSurplusPool);
    function sortedTroves() external view returns (ISortedTroves);
    function interestRouter() external view returns (IInterestRouter);
    function hintHelpers() external view returns (IHintHelpers);
    function multiTroveGetter() external view returns (IMultiTroveGetter);
    function collateralRegistry() external view returns (ICollateralRegistry);
    function boldToken() external view returns (IBoldToken);
    function WETH() external returns (IWETH);

    function setAddresses(AddressVars memory _vars) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IBoldRewardsReceiver {
    function triggerBoldRewards(uint256 _boldYield) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import "openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Permit.sol";
import "openzeppelin-contracts/contracts/interfaces/IERC5267.sol";

interface IBoldToken is IERC20Metadata, IERC20Permit, IERC5267 {
    function setBranchAddresses(
        address _troveManagerAddress,
        address _stabilityPoolAddress,
        address _borrowerOperationsAddress,
        address _activePoolAddress
    ) external;

    function setCollateralRegistry(address _collateralRegistryAddress) external;

    function mint(address _account, uint256 _amount) external;

    function burn(address _account, uint256 _amount) external;

    function sendToPool(address _sender, address poolAddress, uint256 _amount) external;

    function returnFromPool(address poolAddress, address user, uint256 _amount) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./ILiquityBase.sol";
import "./IAddRemoveManagers.sol";
import "./IBoldToken.sol";
import "./IPriceFeed.sol";
import "./ISortedTroves.sol";
import "./ITroveManager.sol";
import "./IWETH.sol";

// Common interface for the Borrower Operations.
interface IBorrowerOperations is ILiquityBase, IAddRemoveManagers {
    function CCR() external view returns (uint256);
    function MCR() external view returns (uint256);
    function SCR() external view returns (uint256);

    function openTrove(
        address _owner,
        uint256 _ownerIndex,
        uint256 _ETHAmount,
        uint256 _boldAmount,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _annualInterestRate,
        uint256 _maxUpfrontFee,
        address _addManager,
        address _removeManager,
        address _receiver
    ) external returns (uint256);

    struct OpenTroveAndJoinInterestBatchManagerParams {
        address owner;
        uint256 ownerIndex;
        uint256 collAmount;
        uint256 boldAmount;
        uint256 upperHint;
        uint256 lowerHint;
        address interestBatchManager;
        uint256 maxUpfrontFee;
        address addManager;
        address removeManager;
        address receiver;
    }

    function openTroveAndJoinInterestBatchManager(OpenTroveAndJoinInterestBatchManagerParams calldata _params)
        external
        returns (uint256);

    function addColl(uint256 _troveId, uint256 _ETHAmount) external;

    function withdrawColl(uint256 _troveId, uint256 _amount) external;

    function withdrawBold(uint256 _troveId, uint256 _amount, uint256 _maxUpfrontFee) external;

    function repayBold(uint256 _troveId, uint256 _amount) external;

    function closeTrove(uint256 _troveId) external;

    function adjustTrove(
        uint256 _troveId,
        uint256 _collChange,
        bool _isCollIncrease,
        uint256 _debtChange,
        bool isDebtIncrease,
        uint256 _maxUpfrontFee
    ) external;

    function adjustZombieTrove(
        uint256 _troveId,
        uint256 _collChange,
        bool _isCollIncrease,
        uint256 _boldChange,
        bool _isDebtIncrease,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external;

    function adjustTroveInterestRate(
        uint256 _troveId,
        uint256 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external;

    function applyPendingDebt(uint256 _troveId, uint256 _lowerHint, uint256 _upperHint) external;

    function onLiquidateTrove(uint256 _troveId) external;

    function claimCollateral() external;

    function hasBeenShutDown() external view returns (bool);
    function shutdown() external;
    function shutdownFromOracleFailure() external;

    function checkBatchManagerExists(address _batchMananger) external view returns (bool);

    // -- individual delegation --
    struct InterestIndividualDelegate {
        address account;
        uint128 minInterestRate;
        uint128 maxInterestRate;
        uint256 minInterestRateChangePeriod;
    }

    function getInterestIndividualDelegateOf(uint256 _troveId)
        external
        view
        returns (InterestIndividualDelegate memory);
    function setInterestIndividualDelegate(
        uint256 _troveId,
        address _delegate,
        uint128 _minInterestRate,
        uint128 _maxInterestRate,
        // only needed if trove was previously in a batch:
        uint256 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee,
        uint256 _minInterestRateChangePeriod
    ) external;
    function removeInterestIndividualDelegate(uint256 _troveId) external;

    // -- batches --
    struct InterestBatchManager {
        uint128 minInterestRate;
        uint128 maxInterestRate;
        uint256 minInterestRateChangePeriod;
    }

    function registerBatchManager(
        uint128 minInterestRate,
        uint128 maxInterestRate,
        uint128 currentInterestRate,
        uint128 fee,
        uint128 minInterestRateChangePeriod
    ) external;
    function lowerBatchManagementFee(uint256 _newAnnualFee) external;
    function setBatchManagerAnnualInterestRate(
        uint128 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external;
    function interestBatchManagerOf(uint256 _troveId) external view returns (address);
    function getInterestBatchManager(address _account) external view returns (InterestBatchManager memory);
    function setInterestBatchManager(
        uint256 _troveId,
        address _newBatchManager,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external;
    function removeFromBatch(
        uint256 _troveId,
        uint256 _newAnnualInterestRate,
        uint256 _upperHint,
        uint256 _lowerHint,
        uint256 _maxUpfrontFee
    ) external;
    function switchBatchManager(
        uint256 _troveId,
        uint256 _removeUpperHint,
        uint256 _removeLowerHint,
        address _newBatchManager,
        uint256 _addUpperHint,
        uint256 _addLowerHint,
        uint256 _maxUpfrontFee
    ) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface ICollSurplusPool {
    function getCollBalance() external view returns (uint256);

    function getCollateral(address _account) external view returns (uint256);

    function accountSurplus(address _account, uint256 _amount) external;

    function claimColl(address _account) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import "./IBoldToken.sol";
import "./ITroveManager.sol";

interface ICollateralRegistry {
    function baseRate() external view returns (uint256);
    function lastFeeOperationTime() external view returns (uint256);

    function redeemCollateral(uint256 _boldamount, uint256 _maxIterations, uint256 _maxFeePercentage) external;
    // getters
    function totalCollaterals() external view returns (uint256);
    function getToken(uint256 _index) external view returns (IERC20Metadata);
    function getTroveManager(uint256 _index) external view returns (ITroveManager);
    function boldToken() external view returns (IBoldToken);

    function getRedemptionRate() external view returns (uint256);
    function getRedemptionRateWithDecay() external view returns (uint256);
    function getRedemptionRateForRedeemedAmount(uint256 _redeemAmount) external view returns (uint256);

    function getRedemptionFeeWithDecay(uint256 _ETHDrawn) external view returns (uint256);
    function getEffectiveRedemptionFeeInBold(uint256 _redeemAmount) external view returns (uint256);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IDefaultPool {
    function troveManagerAddress() external view returns (address);
    function activePoolAddress() external view returns (address);
    // --- Functions ---
    function getCollBalance() external view returns (uint256);
    function getBoldDebt() external view returns (uint256);
    function sendCollToActivePool(uint256 _amount) external;
    function receiveColl(uint256 _amount) external;

    function increaseBoldDebt(uint256 _amount) external;
    function decreaseBoldDebt(uint256 _amount) external;
}

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

pragma solidity ^0.8.0;

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @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 amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

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

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

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

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

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

pragma solidity ^0.8.0;

import "../IERC20.sol";

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

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

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

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)

pragma solidity ^0.8.0;

/**
 * @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 v4.9.0) (interfaces/IERC5267.sol)

pragma solidity ^0.8.0;

interface IERC5267 {
    /**
     * @dev MAY be emitted to signal that the domain could have changed.
     */
    event EIP712DomainChanged();

    /**
     * @dev returns the fields and values that describe the domain separator used by this contract for EIP-712
     * signature.
     */
    function eip712Domain()
        external
        view
        returns (
            bytes1 fields,
            string memory name,
            string memory version,
            uint256 chainId,
            address verifyingContract,
            bytes32 salt,
            uint256[] memory extensions
        );
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.0;

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

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

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

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

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

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

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

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

    /**
     * @dev Transfers `tokenId` token from `from` to `to`.
     *
     * WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC721
     * or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
     * understand this adds an external call which potentially creates a reentrancy vulnerability.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `tokenId` token must be owned by `from`.
     * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address from, address to, uint256 tokenId) external;

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

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

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

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

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

pragma solidity ^0.8.0;

import "../IERC721.sol";

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

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

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

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IHintHelpers {
    function getApproxHint(uint256 _collIndex, uint256 _interestRate, uint256 _numTrials, uint256 _inputRandomSeed)
        external
        view
        returns (uint256 hintId, uint256 diff, uint256 latestRandomSeed);

    function predictOpenTroveUpfrontFee(uint256 _collIndex, uint256 _borrowedAmount, uint256 _interestRate)
        external
        view
        returns (uint256);

    function predictAdjustInterestRateUpfrontFee(uint256 _collIndex, uint256 _troveId, uint256 _newInterestRate)
        external
        view
        returns (uint256);

    function forcePredictAdjustInterestRateUpfrontFee(uint256 _collIndex, uint256 _troveId, uint256 _newInterestRate)
        external
        view
        returns (uint256);

    function predictAdjustTroveUpfrontFee(uint256 _collIndex, uint256 _troveId, uint256 _debtIncrease)
        external
        view
        returns (uint256);

    function predictAdjustBatchInterestRateUpfrontFee(
        uint256 _collIndex,
        address _batchAddress,
        uint256 _newInterestRate
    ) external view returns (uint256);

    function predictJoinBatchInterestRateUpfrontFee(uint256 _collIndex, uint256 _troveId, address _batchAddress)
        external
        view
        returns (uint256);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IInterestRouter {
// Currently the Interest Router doesn’t need any specific function
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IActivePool.sol";
import "./IDefaultPool.sol";
import "./IPriceFeed.sol";

interface ILiquityBase {
    function activePool() external view returns (IActivePool);
    function getEntireSystemDebt() external view returns (uint256);
    function getEntireSystemColl() external view returns (uint256);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IMultiTroveGetter {
    struct CombinedTroveData {
        uint256 id;
        uint256 debt;
        uint256 coll;
        uint256 stake;
        uint256 annualInterestRate;
        uint256 lastDebtUpdateTime;
        uint256 lastInterestRateAdjTime;
        address interestBatchManager;
        uint256 batchDebtShares;
        uint256 batchCollShares;
        uint256 snapshotETH;
        uint256 snapshotBoldDebt;
    }

    struct DebtPerInterestRate {
        address interestBatchManager;
        uint256 interestRate;
        uint256 debt;
    }

    function getMultipleSortedTroves(uint256 _collIndex, int256 _startIdx, uint256 _count)
        external
        view
        returns (CombinedTroveData[] memory _troves);

    function getDebtPerInterestRateAscending(uint256 _collIndex, uint256 _startId, uint256 _maxIterations)
        external
        view
        returns (DebtPerInterestRate[] memory, uint256 currId);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

interface IPriceFeed {
    function fetchPrice() external returns (uint256, bool);
    function fetchRedemptionPrice() external returns (uint256, bool);
    function lastGoodPrice() external view returns (uint256);
    function setAddresses(address _borrowerOperationsAddress) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./ITroveManager.sol";
import {BatchId, BATCH_ID_ZERO} from "../Types/BatchId.sol";

interface ISortedTroves {
    // -- Mutating functions (permissioned) --
    function insert(uint256 _id, uint256 _annualInterestRate, uint256 _prevId, uint256 _nextId) external;
    function insertIntoBatch(
        uint256 _troveId,
        BatchId _batchId,
        uint256 _annualInterestRate,
        uint256 _prevId,
        uint256 _nextId
    ) external;

    function remove(uint256 _id) external;
    function removeFromBatch(uint256 _id) external;

    function reInsert(uint256 _id, uint256 _newAnnualInterestRate, uint256 _prevId, uint256 _nextId) external;
    function reInsertBatch(BatchId _id, uint256 _newAnnualInterestRate, uint256 _prevId, uint256 _nextId) external;

    // -- View functions --

    function contains(uint256 _id) external view returns (bool);
    function isBatchedNode(uint256 _id) external view returns (bool);
    function isEmptyBatch(BatchId _id) external view returns (bool);

    function isEmpty() external view returns (bool);
    function getSize() external view returns (uint256);

    function getFirst() external view returns (uint256);
    function getLast() external view returns (uint256);
    function getNext(uint256 _id) external view returns (uint256);
    function getPrev(uint256 _id) external view returns (uint256);

    function validInsertPosition(uint256 _annualInterestRate, uint256 _prevId, uint256 _nextId)
        external
        view
        returns (bool);
    function findInsertPosition(uint256 _annualInterestRate, uint256 _prevId, uint256 _nextId)
        external
        view
        returns (uint256, uint256);

    // Public state variable getters
    function borrowerOperationsAddress() external view returns (address);
    function troveManager() external view returns (ITroveManager);
    function size() external view returns (uint256);
    function nodes(uint256 _id) external view returns (uint256 nextId, uint256 prevId, BatchId batchId, bool exists);
    function batches(BatchId _id) external view returns (uint256 head, uint256 tail);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IActivePool.sol";
import "./ILiquityBase.sol";
import "./IBoldToken.sol";
import "./ITroveManager.sol";
import "./IBoldRewardsReceiver.sol";

/*
 * The Stability Pool holds Bold tokens deposited by Stability Pool depositors.
 *
 * When a trove is liquidated, then depending on system conditions, some of its Bold debt gets offset with
 * Bold in the Stability Pool:  that is, the offset debt evaporates, and an equal amount of Bold tokens in the Stability Pool is burned.
 *
 * Thus, a liquidation causes each depositor to receive a Bold loss, in proportion to their deposit as a share of total deposits.
 * They also receive an Coll gain, as the collateral of the liquidated trove is distributed among Stability depositors,
 * in the same proportion.
 *
 * When a liquidation occurs, it depletes every deposit by the same fraction: for example, a liquidation that depletes 40%
 * of the total Bold in the Stability Pool, depletes 40% of each deposit.
 *
 * A deposit that has experienced a series of liquidations is termed a "compounded deposit": each liquidation depletes the deposit,
 * multiplying it by some factor in range ]0,1[
 *
 * Please see the implementation spec in the proof document, which closely follows on from the compounded deposit / Coll gain derivations:
 * https://github.com/liquity/liquity/blob/master/papers/Scalable_Reward_Distribution_with_Compounding_Stakes.pdf
 *
*/
interface IStabilityPool is ILiquityBase, IBoldRewardsReceiver {
    function boldToken() external view returns (IBoldToken);
    function troveManager() external view returns (ITroveManager);

    /*  provideToSP():
    * - Calculates depositor's Coll gain
    * - Calculates the compounded deposit
    * - Increases deposit, and takes new snapshots of accumulators P and S
    * - Sends depositor's accumulated Coll gains to depositor
    */
    function provideToSP(uint256 _amount, bool _doClaim) external;

    /*  withdrawFromSP():
    * - Calculates depositor's Coll gain
    * - Calculates the compounded deposit
    * - Sends the requested BOLD withdrawal to depositor
    * - (If _amount > userDeposit, the user withdraws all of their compounded deposit)
    * - Decreases deposit by withdrawn amount and takes new snapshots of accumulators P and S
    */
    function withdrawFromSP(uint256 _amount, bool doClaim) external;

    function claimAllCollGains() external;

    /*
     * Initial checks:
     * - Caller is TroveManager
     * ---
     * Cancels out the specified debt against the Bold contained in the Stability Pool (as far as possible)
     * and transfers the Trove's collateral from ActivePool to StabilityPool.
     * Only called by liquidation functions in the TroveManager.
     */
    function offset(uint256 _debt, uint256 _coll) external;

    function deposits(address _depositor) external view returns (uint256 initialValue);
    function stashedColl(address _depositor) external view returns (uint256);

    /*
     * Returns the total amount of Coll held by the pool, accounted in an internal variable instead of `balance`,
     * to exclude edge cases like Coll received from a self-destruct.
     */
    function getCollBalance() external view returns (uint256);

    /*
     * Returns Bold held in the pool. Changes when users deposit/withdraw, and when Trove debt is offset.
     */
    function getTotalBoldDeposits() external view returns (uint256);

    function getYieldGainsOwed() external view returns (uint256);
    function getYieldGainsPending() external view returns (uint256);

    /*
     * Calculates the Coll gain earned by the deposit since its last snapshots were taken.
     */
    function getDepositorCollGain(address _depositor) external view returns (uint256);

    /*
     * Calculates the BOLD yield gain earned by the deposit since its last snapshots were taken.
     */
    function getDepositorYieldGain(address _depositor) external view returns (uint256);

    /*
     * Calculates what `getDepositorYieldGain` will be if interest is minted now.
     */
    function getDepositorYieldGainWithPending(address _depositor) external view returns (uint256);

    /*
     * Return the user's compounded deposit.
     */
    function getCompoundedBoldDeposit(address _depositor) external view returns (uint256);

    function epochToScaleToS(uint128 _epoch, uint128 _scale) external view returns (uint256);

    function epochToScaleToB(uint128 _epoch, uint128 _scale) external view returns (uint256);

    function P() external view returns (uint256);
    function currentScale() external view returns (uint128);
    function currentEpoch() external view returns (uint128);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./ILiquityBase.sol";
import "./ITroveNFT.sol";
import "./IBorrowerOperations.sol";
import "./IStabilityPool.sol";
import "./IBoldToken.sol";
import "./ISortedTroves.sol";
import "../Types/LatestTroveData.sol";
import "../Types/LatestBatchData.sol";

// Common interface for the Trove Manager.
interface ITroveManager is ILiquityBase {
    enum Status {
        nonExistent,
        active,
        closedByOwner,
        closedByLiquidation,
        zombie
    }

    function shutdownTime() external view returns (uint256);

    function troveNFT() external view returns (ITroveNFT);
    function stabilityPool() external view returns (IStabilityPool);
    //function boldToken() external view returns (IBoldToken);
    function sortedTroves() external view returns (ISortedTroves);
    function borrowerOperations() external view returns (IBorrowerOperations);

    function Troves(uint256 _id)
        external
        view
        returns (
            uint256 debt,
            uint256 coll,
            uint256 stake,
            Status status,
            uint64 arrayIndex,
            uint64 lastDebtUpdateTime,
            uint64 lastInterestRateAdjTime,
            uint256 annualInterestRate,
            address interestBatchManager,
            uint256 batchDebtShares
        );

    function rewardSnapshots(uint256 _id) external view returns (uint256 coll, uint256 boldDebt);

    function getTroveIdsCount() external view returns (uint256);

    function getTroveFromTroveIdsArray(uint256 _index) external view returns (uint256);

    function getCurrentICR(uint256 _troveId, uint256 _price) external view returns (uint256);

    function lastZombieTroveId() external view returns (uint256);

    function batchLiquidateTroves(uint256[] calldata _troveArray) external;

    function redeemCollateral(
        address _sender,
        uint256 _boldAmount,
        uint256 _price,
        uint256 _redemptionRate,
        uint256 _maxIterations
    ) external returns (uint256 _redemeedAmount);

    function shutdown() external;
    function urgentRedemption(uint256 _boldAmount, uint256[] calldata _troveIds, uint256 _minCollateral) external;

    function getUnbackedPortionPriceAndRedeemability() external returns (uint256, uint256, bool);

    function getLatestTroveData(uint256 _troveId) external view returns (LatestTroveData memory);
    function getTroveAnnualInterestRate(uint256 _troveId) external view returns (uint256);

    function getTroveStatus(uint256 _troveId) external view returns (Status);

    function getLatestBatchData(address _batchAddress) external view returns (LatestBatchData memory);

    // -- permissioned functions called by BorrowerOperations

    function onOpenTrove(address _owner, uint256 _troveId, TroveChange memory _troveChange, uint256 _annualInterestRate)
        external;
    function onOpenTroveAndJoinBatch(
        address _owner,
        uint256 _troveId,
        TroveChange memory _troveChange,
        address _batchAddress,
        uint256 _batchColl,
        uint256 _batchDebt
    ) external;

    // Called from `adjustZombieTrove()`
    function setTroveStatusToActive(uint256 _troveId) external;

    function onAdjustTroveInterestRate(
        uint256 _troveId,
        uint256 _newColl,
        uint256 _newDebt,
        uint256 _newAnnualInterestRate,
        TroveChange calldata _troveChange
    ) external;

    function onAdjustTrove(uint256 _troveId, uint256 _newColl, uint256 _newDebt, TroveChange calldata _troveChange)
        external;

    function onAdjustTroveInsideBatch(
        uint256 _troveId,
        uint256 _newTroveColl,
        uint256 _newTroveDebt,
        TroveChange memory _troveChange,
        address _batchAddress,
        uint256 _newBatchColl,
        uint256 _newBatchDebt
    ) external;

    function onApplyTroveInterest(
        uint256 _troveId,
        uint256 _newTroveColl,
        uint256 _newTroveDebt,
        address _batchAddress,
        uint256 _newBatchColl,
        uint256 _newBatchDebt,
        TroveChange calldata _troveChange
    ) external;

    function onCloseTrove(
        uint256 _troveId,
        TroveChange memory _troveChange, // decrease vars: entire, with interest, batch fee and redistribution
        address _batchAddress,
        uint256 _newBatchColl,
        uint256 _newBatchDebt // entire, with interest and batch fee
    ) external;

    // -- batches --
    function onRegisterBatchManager(address _batchAddress, uint256 _annualInterestRate, uint256 _annualFee) external;
    function onLowerBatchManagerAnnualFee(
        address _batchAddress,
        uint256 _newColl,
        uint256 _newDebt,
        uint256 _newAnnualManagementFee
    ) external;
    function onSetBatchManagerAnnualInterestRate(
        address _batchAddress,
        uint256 _newColl,
        uint256 _newDebt,
        uint256 _newAnnualInterestRate,
        uint256 _upfrontFee // needed by BatchUpdated event
    ) external;

    struct OnSetInterestBatchManagerParams {
        uint256 troveId;
        uint256 troveColl; // entire, with redistribution
        uint256 troveDebt; // entire, with interest, batch fee and redistribution
        TroveChange troveChange;
        address newBatchAddress;
        uint256 newBatchColl; // updated collateral for new batch manager
        uint256 newBatchDebt; // updated debt for new batch manager
    }

    function onSetInterestBatchManager(OnSetInterestBatchManagerParams calldata _params) external;
    function onRemoveFromBatch(
        uint256 _troveId,
        uint256 _newTroveColl, // entire, with redistribution
        uint256 _newTroveDebt, // entire, with interest, batch fee and redistribution
        TroveChange memory _troveChange,
        address _batchAddress,
        uint256 _newBatchColl,
        uint256 _newBatchDebt, // entire, with interest and batch fee
        uint256 _newAnnualInterestRate
    ) external;

    // -- end of permissioned functions --
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "openzeppelin-contracts/contracts/token/ERC721/extensions/IERC721Metadata.sol";

import "./ITroveManager.sol";

interface ITroveNFT is IERC721Metadata {
    function mint(address _owner, uint256 _troveId) external;
    function burn(uint256 _troveId) external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol";

interface IWETH is IERC20Metadata {
    function deposit() external payable;
    function withdraw(uint256 wad) external;
}

//SPDX-License-Identifier: MIT
pragma solidity ^0.8.12;

// JSON utilities for base64 encoded ERC721 JSON metadata scheme
library json {
    /////////////////////////////////////////////////////////////////////////////////////////////////////////////
    /// @dev JSON requires that double quotes be escaped or JSONs will not build correctly
    /// string.concat also requires an escape, use \\" or the constant DOUBLE_QUOTES to represent " in JSON
    /////////////////////////////////////////////////////////////////////////////////////////////////////////////

    string constant DOUBLE_QUOTES = '\\"';

    function formattedMetadata(
        string memory name,
        string memory description,
        string memory svgImg,
        string memory attributes
    ) internal pure returns (string memory) {
        return string.concat(
            "data:application/json;base64,",
            encode(
                bytes(
                    string.concat(
                        "{",
                        _prop("name", name),
                        _prop("description", description),
                        _xmlImage(svgImg),
                        ',"attributes":',
                        attributes,
                        "}"
                    )
                )
            )
        );
    }

    function _xmlImage(string memory _svgImg) internal pure returns (string memory) {
        return _prop("image", string.concat("data:image/svg+xml;base64,", encode(bytes(_svgImg))), true);
    }

    function _prop(string memory _key, string memory _val) internal pure returns (string memory) {
        return string.concat('"', _key, '": ', '"', _val, '", ');
    }

    function _prop(string memory _key, string memory _val, bool last) internal pure returns (string memory) {
        if (last) {
            return string.concat('"', _key, '": ', '"', _val, '"');
        } else {
            return string.concat('"', _key, '": ', '"', _val, '", ');
        }
    }

    function _object(string memory _key, string memory _val) internal pure returns (string memory) {
        return string.concat('"', _key, '": ', "{", _val, "}");
    }

    /**
     * taken from Openzeppelin
     * @dev Base64 Encoding/Decoding Table
     */
    string internal constant _TABLE = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

    /**
     * @dev Converts a `bytes` to its Bytes64 `string` representation.
     */
    function encode(bytes memory data) internal pure returns (string memory) {
        /**
         * Inspired by Brecht Devos (Brechtpd) implementation - MIT licence
         * https://github.com/Brechtpd/base64/blob/e78d9fd951e7b0977ddca77d92dc85183770daf4/base64.sol
         */
        if (data.length == 0) return "";

        // Loads the table into memory
        string memory table = _TABLE;

        // Encoding takes 3 bytes chunks of binary data from `bytes` data parameter
        // and split into 4 numbers of 6 bits.
        // The final Base64 length should be `bytes` data length multiplied by 4/3 rounded up
        // - `data.length + 2`  -> Round up
        // - `/ 3`              -> Number of 3-bytes chunks
        // - `4 *`              -> 4 characters for each chunk
        string memory result = new string(4 * ((data.length + 2) / 3));

        assembly {
            // Prepare the lookup table (skip the first "length" byte)
            let tablePtr := add(table, 1)

            // Prepare result pointer, jump over length
            let resultPtr := add(result, 32)

            // Run over the input, 3 bytes at a time
            for {
                let dataPtr := data
                let endPtr := add(data, mload(data))
            } lt(dataPtr, endPtr) {} {
                // Advance 3 bytes
                dataPtr := add(dataPtr, 3)
                let input := mload(dataPtr)

                // To write each character, shift the 3 bytes (18 bits) chunk
                // 4 times in blocks of 6 bits for each character (18, 12, 6, 0)
                // and apply logical AND with 0x3F which is the number of
                // the previous character in the ASCII table prior to the Base64 Table
                // The result is then added to the table to get the character to write,
                // and finally write it in the result pointer but with a left shift
                // of 256 (1 byte) - 8 (1 ASCII char) = 248 bits

                mstore8(resultPtr, mload(add(tablePtr, and(shr(18, input), 0x3F))))
                resultPtr := add(resultPtr, 1) // Advance

                mstore8(resultPtr, mload(add(tablePtr, and(shr(12, input), 0x3F))))
                resultPtr := add(resultPtr, 1) // Advance

                mstore8(resultPtr, mload(add(tablePtr, and(shr(6, input), 0x3F))))
                resultPtr := add(resultPtr, 1) // Advance

                mstore8(resultPtr, mload(add(tablePtr, and(input, 0x3F))))
                resultPtr := add(resultPtr, 1) // Advance
            }

            // When data `bytes` is not exactly 3 bytes long
            // it is padded with `=` characters at the end
            switch mod(mload(data), 3)
            case 1 {
                mstore8(sub(resultPtr, 1), 0x3d)
                mstore8(sub(resultPtr, 2), 0x3d)
            }
            case 2 { mstore8(sub(resultPtr, 1), 0x3d) }
        }

        return result;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity 0.8.24;

struct LatestBatchData {
    uint256 entireDebtWithoutRedistribution;
    uint256 entireCollWithoutRedistribution;
    uint256 accruedInterest;
    uint256 recordedDebt;
    uint256 annualInterestRate;
    uint256 weightedRecordedDebt;
    uint256 annualManagementFee;
    uint256 accruedManagementFee;
    uint256 weightedRecordedBatchManagementFee;
    uint256 lastDebtUpdateTime;
    uint256 lastInterestRateAdjTime;
}

// SPDX-License-Identifier: MIT

pragma solidity 0.8.24;

struct LatestTroveData {
    uint256 entireDebt;
    uint256 entireColl;
    uint256 redistBoldDebtGain;
    uint256 redistCollGain;
    uint256 accruedInterest;
    uint256 recordedDebt;
    uint256 annualInterestRate;
    uint256 weightedRecordedDebt;
    uint256 accruedBatchManagementFee;
    uint256 lastInterestRateAdjTime;
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

/// @notice Library for converting numbers into strings and other string operations.
/// @author Solady (https://github.com/vectorized/solady/blob/main/src/utils/LibString.sol)
/// @author Modified from Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/LibString.sol)
///
/// @dev Note:
/// For performance and bytecode compactness, most of the string operations are restricted to
/// byte strings (7-bit ASCII), except where otherwise specified.
/// Usage of byte string operations on charsets with runes spanning two or more bytes
/// can lead to undefined behavior.
library LibString {
    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                        CUSTOM ERRORS                       */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The length of the output is too small to contain all the hex digits.
    error HexLengthInsufficient();

    /// @dev The length of the string is more than 32 bytes.
    error TooBigForSmallString();

    /// @dev The input string must be a 7-bit ASCII.
    error StringNot7BitASCII();

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                         CONSTANTS                          */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev The constant returned when the `search` is not found in the string.
    uint256 internal constant NOT_FOUND = type(uint256).max;

    /// @dev Lookup for '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'.
    uint128 internal constant ALPHANUMERIC_7_BIT_ASCII = 0x7fffffe07fffffe03ff000000000000;

    /// @dev Lookup for 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'.
    uint128 internal constant LETTERS_7_BIT_ASCII = 0x7fffffe07fffffe0000000000000000;

    /// @dev Lookup for 'abcdefghijklmnopqrstuvwxyz'.
    uint128 internal constant LOWERCASE_7_BIT_ASCII = 0x7fffffe000000000000000000000000;

    /// @dev Lookup for 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'.
    uint128 internal constant UPPERCASE_7_BIT_ASCII = 0x7fffffe0000000000000000;

    /// @dev Lookup for '0123456789'.
    uint128 internal constant DIGITS_7_BIT_ASCII = 0x3ff000000000000;

    /// @dev Lookup for '0123456789abcdefABCDEF'.
    uint128 internal constant HEXDIGITS_7_BIT_ASCII = 0x7e0000007e03ff000000000000;

    /// @dev Lookup for '01234567'.
    uint128 internal constant OCTDIGITS_7_BIT_ASCII = 0xff000000000000;

    /// @dev Lookup for '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~ \t\n\r\x0b\x0c'.
    uint128 internal constant PRINTABLE_7_BIT_ASCII = 0x7fffffffffffffffffffffff00003e00;

    /// @dev Lookup for '!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~'.
    uint128 internal constant PUNCTUATION_7_BIT_ASCII = 0x78000001f8000001fc00fffe00000000;

    /// @dev Lookup for ' \t\n\r\x0b\x0c'.
    uint128 internal constant WHITESPACE_7_BIT_ASCII = 0x100003e00;

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                     DECIMAL OPERATIONS                     */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the base 10 decimal representation of `value`.
    function toString(uint256 value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            // The maximum value of a uint256 contains 78 digits (1 byte per digit), but
            // we allocate 0xa0 bytes to keep the free memory pointer 32-byte word aligned.
            // We will need 1 word for the trailing zeros padding, 1 word for the length,
            // and 3 words for a maximum of 78 digits.
            str := add(mload(0x40), 0x80)
            mstore(0x40, add(str, 0x20)) // Allocate the memory.
            mstore(str, 0) // Zeroize the slot after the string.

            let end := str // Cache the end of the memory to calculate the length later.
            let w := not(0) // Tsk.
            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for { let temp := value } 1 {} {
                str := add(str, w) // `sub(str, 1)`.
                // Store the character to the pointer.
                // The ASCII index of the '0' character is 48.
                mstore8(str, add(48, mod(temp, 10)))
                temp := div(temp, 10) // Keep dividing `temp` until zero.
                if iszero(temp) { break }
            }
            let length := sub(end, str)
            str := sub(str, 0x20) // Move the pointer 32 bytes back to make room for the length.
            mstore(str, length) // Store the length.
        }
    }

    /// @dev Returns the base 10 decimal representation of `value`.
    function toString(int256 value) internal pure returns (string memory str) {
        if (value >= 0) return toString(uint256(value));
        unchecked {
            str = toString(~uint256(value) + 1);
        }
        /// @solidity memory-safe-assembly
        assembly {
            // We still have some spare memory space on the left,
            // as we have allocated 3 words (96 bytes) for up to 78 digits.
            let length := mload(str) // Load the string length.
            mstore(str, 0x2d) // Store the '-' character.
            str := sub(str, 1) // Move back the string pointer by a byte.
            mstore(str, add(length, 1)) // Update the string length.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   HEXADECIMAL OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the hexadecimal representation of `value`,
    /// left-padded to an input length of `length` bytes.
    /// The output is prefixed with "0x" encoded using 2 hexadecimal digits per byte,
    /// giving a total length of `length * 2 + 2` bytes.
    /// Reverts if `length` is too small for the output to contain all the digits.
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value, length);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Store the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Store the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`,
    /// left-padded to an input length of `length` bytes.
    /// The output is prefixed with "0x" encoded using 2 hexadecimal digits per byte,
    /// giving a total length of `length * 2` bytes.
    /// Reverts if `length` is too small for the output to contain all the digits.
    function toHexStringNoPrefix(uint256 value, uint256 length)
        internal
        pure
        returns (string memory str)
    {
        /// @solidity memory-safe-assembly
        assembly {
            // We need 0x20 bytes for the trailing zeros padding, `length * 2` bytes
            // for the digits, 0x02 bytes for the prefix, and 0x20 bytes for the length.
            // We add 0x20 to the total and round down to a multiple of 0x20.
            // (0x20 + 0x20 + 0x02 + 0x20) = 0x62.
            str := add(mload(0x40), and(add(shl(1, length), 0x42), not(0x1f)))
            mstore(0x40, add(str, 0x20)) // Allocate the memory.
            mstore(str, 0) // Zeroize the slot after the string.

            let end := str // Cache the end to calculate the length later.
            // Store "0123456789abcdef" in scratch space.
            mstore(0x0f, 0x30313233343536373839616263646566)

            let start := sub(str, add(length, length))
            let w := not(1) // Tsk.
            let temp := value
            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for {} 1 {} {
                str := add(str, w) // `sub(str, 2)`.
                mstore8(add(str, 1), mload(and(temp, 15)))
                mstore8(str, mload(and(shr(4, temp), 15)))
                temp := shr(8, temp)
                if iszero(xor(str, start)) { break }
            }
            if temp {
                mstore(0x00, 0x2194895a) // `HexLengthInsufficient()`.
                revert(0x1c, 0x04)
            }
            let strLength := sub(end, str)
            str := sub(str, 0x20)
            mstore(str, strLength) // Store the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x" and encoded using 2 hexadecimal digits per byte.
    /// As address are 20 bytes long, the output will left-padded to have
    /// a length of `20 * 2 + 2` bytes.
    function toHexString(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Store the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Store the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x".
    /// The output excludes leading "0" from the `toHexString` output.
    /// `0x00: "0x0", 0x01: "0x1", 0x12: "0x12", 0x123: "0x123"`.
    function toMinimalHexString(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let o := eq(byte(0, mload(add(str, 0x20))), 0x30) // Whether leading zero is present.
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(add(str, o), 0x3078) // Store the "0x" prefix, accounting for leading zero.
            str := sub(add(str, o), 2) // Move the pointer, accounting for leading zero.
            mstore(str, sub(strLength, o)) // Store the length, accounting for leading zero.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output excludes leading "0" from the `toHexStringNoPrefix` output.
    /// `0x00: "0", 0x01: "1", 0x12: "12", 0x123: "123"`.
    function toMinimalHexStringNoPrefix(uint256 value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let o := eq(byte(0, mload(add(str, 0x20))), 0x30) // Whether leading zero is present.
            let strLength := mload(str) // Get the length.
            str := add(str, o) // Move the pointer, accounting for leading zero.
            mstore(str, sub(strLength, o)) // Store the length, accounting for leading zero.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is encoded using 2 hexadecimal digits per byte.
    /// As address are 20 bytes long, the output will left-padded to have
    /// a length of `20 * 2` bytes.
    function toHexStringNoPrefix(uint256 value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            // We need 0x20 bytes for the trailing zeros padding, 0x20 bytes for the length,
            // 0x02 bytes for the prefix, and 0x40 bytes for the digits.
            // The next multiple of 0x20 above (0x20 + 0x20 + 0x02 + 0x40) is 0xa0.
            str := add(mload(0x40), 0x80)
            mstore(0x40, add(str, 0x20)) // Allocate the memory.
            mstore(str, 0) // Zeroize the slot after the string.

            let end := str // Cache the end to calculate the length later.
            mstore(0x0f, 0x30313233343536373839616263646566) // Store the "0123456789abcdef" lookup.

            let w := not(1) // Tsk.
            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for { let temp := value } 1 {} {
                str := add(str, w) // `sub(str, 2)`.
                mstore8(add(str, 1), mload(and(temp, 15)))
                mstore8(str, mload(and(shr(4, temp), 15)))
                temp := shr(8, temp)
                if iszero(temp) { break }
            }
            let strLength := sub(end, str)
            str := sub(str, 0x20)
            mstore(str, strLength) // Store the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x", encoded using 2 hexadecimal digits per byte,
    /// and the alphabets are capitalized conditionally according to
    /// https://eips.ethereum.org/EIPS/eip-55
    function toHexStringChecksummed(address value) internal pure returns (string memory str) {
        str = toHexString(value);
        /// @solidity memory-safe-assembly
        assembly {
            let mask := shl(6, div(not(0), 255)) // `0b010000000100000000 ...`
            let o := add(str, 0x22)
            let hashed := and(keccak256(o, 40), mul(34, mask)) // `0b10001000 ... `
            let t := shl(240, 136) // `0b10001000 << 240`
            for { let i := 0 } 1 {} {
                mstore(add(i, i), mul(t, byte(i, hashed)))
                i := add(i, 1)
                if eq(i, 20) { break }
            }
            mstore(o, xor(mload(o), shr(1, and(mload(0x00), and(mload(o), mask)))))
            o := add(o, 0x20)
            mstore(o, xor(mload(o), shr(1, and(mload(0x20), and(mload(o), mask)))))
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is prefixed with "0x" and encoded using 2 hexadecimal digits per byte.
    function toHexString(address value) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(value);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Store the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Store the length.
        }
    }

    /// @dev Returns the hexadecimal representation of `value`.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(address value) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            str := mload(0x40)
            // Allocate the memory.
            // We need 0x20 bytes for the trailing zeros padding, 0x20 bytes for the length,
            // 0x02 bytes for the prefix, and 0x28 bytes for the digits.
            // The next multiple of 0x20 above (0x20 + 0x20 + 0x02 + 0x28) is 0x80.
            mstore(0x40, add(str, 0x80))
            mstore(0x0f, 0x30313233343536373839616263646566) // Store the "0123456789abcdef" lookup.

            str := add(str, 2)
            mstore(str, 40) // Store the length.
            let o := add(str, 0x20)
            mstore(add(o, 40), 0) // Zeroize the slot after the string.
            value := shl(96, value)
            // We write the string from rightmost digit to leftmost digit.
            // The following is essentially a do-while loop that also handles the zero case.
            for { let i := 0 } 1 {} {
                let p := add(o, add(i, i))
                let temp := byte(i, value)
                mstore8(add(p, 1), mload(and(temp, 15)))
                mstore8(p, mload(shr(4, temp)))
                i := add(i, 1)
                if eq(i, 20) { break }
            }
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexString(bytes memory raw) internal pure returns (string memory str) {
        str = toHexStringNoPrefix(raw);
        /// @solidity memory-safe-assembly
        assembly {
            let strLength := add(mload(str), 2) // Compute the length.
            mstore(str, 0x3078) // Store the "0x" prefix.
            str := sub(str, 2) // Move the pointer.
            mstore(str, strLength) // Store the length.
        }
    }

    /// @dev Returns the hex encoded string from the raw bytes.
    /// The output is encoded using 2 hexadecimal digits per byte.
    function toHexStringNoPrefix(bytes memory raw) internal pure returns (string memory str) {
        /// @solidity memory-safe-assembly
        assembly {
            let length := mload(raw)
            str := add(mload(0x40), 2) // Skip 2 bytes for the optional prefix.
            mstore(str, add(length, length)) // Store the length of the output.

            mstore(0x0f, 0x30313233343536373839616263646566) // Store the "0123456789abcdef" lookup.
            let o := add(str, 0x20)
            let end := add(raw, length)
            for {} iszero(eq(raw, end)) {} {
                raw := add(raw, 1)
                mstore8(add(o, 1), mload(and(mload(raw), 15)))
                mstore8(o, mload(and(shr(4, mload(raw)), 15)))
                o := add(o, 2)
            }
            mstore(o, 0) // Zeroize the slot after the string.
            mstore(0x40, add(o, 0x20)) // Allocate the memory.
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   RUNE STRING OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    /// @dev Returns the number of UTF characters in the string.
    function runeCount(string memory s) internal pure returns (uint256 result) {
        /// @solidity memory-safe-assembly
        assembly {
            if mload(s) {
                mstore(0x00, div(not(0), 255))
                mstore(0x20, 0x0202020202020202020202020202020202020202020202020303030304040506)
                let o := add(s, 0x20)
                let end := add(o, mload(s))
                for { result := 1 } 1 { result := add(result, 1) } {
                    o := add(o, byte(0, mload(shr(250, mload(o)))))
                    if iszero(lt(o, end)) { break }
                }
            }
        }
    }

    /// @dev Returns if this string is a 7-bit ASCII string.
    /// (i.e. all characters codes are in [0..127])
    function is7BitASCII(string memory s) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            let mask := shl(7, div(not(0), 255))
            result := 1
            let n := mload(s)
            if n {
                let o := add(s, 0x20)
                let end := add(o, n)
                let last := mload(end)
                mstore(end, 0)
                for {} 1 {} {
                    if and(mask, mload(o)) {
                        result := 0
                        break
                    }
                    o := add(o, 0x20)
                    if iszero(lt(o, end)) { break }
                }
                mstore(end, last)
            }
        }
    }

    /// @dev Returns if this string is a 7-bit ASCII string,
    /// AND all characters are in the `allowed` lookup.
    /// Note: If `s` is empty, returns true regardless of `allowed`.
    function is7BitASCII(string memory s, uint128 allowed) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := 1
            if mload(s) {
                let allowed_ := shr(128, shl(128, allowed))
                let o := add(s, 0x20)
                let end := add(o, mload(s))
                for {} 1 {} {
                    result := and(result, shr(byte(0, mload(o)), allowed_))
                    o := add(o, 1)
                    if iszero(and(result, lt(o, end))) { break }
                }
            }
        }
    }

    /// @dev Converts the bytes in the 7-bit ASCII string `s` to
    /// an allowed lookup for use in `is7BitASCII(s, allowed)`.
    /// To save runtime gas, you can cache the result in an immutable variable.
    function to7BitASCIIAllowedLookup(string memory s) internal pure returns (uint128 result) {
        /// @solidity memory-safe-assembly
        assembly {
            if mload(s) {
                let o := add(s, 0x20)
                let end := add(o, mload(s))
                for {} 1 {} {
                    result := or(result, shl(byte(0, mload(o)), 1))
                    o := add(o, 1)
                    if iszero(lt(o, end)) { break }
                }
                if shr(128, result) {
                    mstore(0x00, 0xc9807e0d) // `StringNot7BitASCII()`.
                    revert(0x1c, 0x04)
                }
            }
        }
    }

    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
    /*                   BYTE STRING OPERATIONS                   */
    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/

    // For performance and bytecode compactness, byte string operations are restricted
    // to 7-bit ASCII strings. All offsets are byte offsets, not UTF character offsets.
    // Usage of byte string operations on charsets with runes spanning two or more bytes
    // can lead to undefined behavior.

    /// @dev Returns `subject` all occurrences of `search` replaced with `replacement`.
    function replace(string memory subject, string memory search, string memory replacement)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            let searchLength := mload(search)
            let replacementLength := mload(replacement)

            subject := add(subject, 0x20)
            search := add(search, 0x20)
            replacement := add(replacement, 0x20)
            result := add(mload(0x40), 0x20)

            let subjectEnd := add(subject, subjectLength)
            if iszero(gt(searchLength, subjectLength)) {
                let subjectSearchEnd := add(sub(subjectEnd, searchLength), 1)
                let h := 0
                if iszero(lt(searchLength, 0x20)) { h := keccak256(search, searchLength) }
                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(search)
                for {} 1 {} {
                    let t := mload(subject)
                    // Whether the first `searchLength % 32` bytes of
                    // `subject` and `search` matches.
                    if iszero(shr(m, xor(t, s))) {
                        if h {
                            if iszero(eq(keccak256(subject, searchLength), h)) {
                                mstore(result, t)
                                result := add(result, 1)
                                subject := add(subject, 1)
                                if iszero(lt(subject, subjectSearchEnd)) { break }
                                continue
                            }
                        }
                        // Copy the `replacement` one word at a time.
                        for { let o := 0 } 1 {} {
                            mstore(add(result, o), mload(add(replacement, o)))
                            o := add(o, 0x20)
                            if iszero(lt(o, replacementLength)) { break }
                        }
                        result := add(result, replacementLength)
                        subject := add(subject, searchLength)
                        if searchLength {
                            if iszero(lt(subject, subjectSearchEnd)) { break }
                            continue
                        }
                    }
                    mstore(result, t)
                    result := add(result, 1)
                    subject := add(subject, 1)
                    if iszero(lt(subject, subjectSearchEnd)) { break }
                }
            }

            let resultRemainder := result
            result := add(mload(0x40), 0x20)
            let k := add(sub(resultRemainder, result), sub(subjectEnd, subject))
            // Copy the rest of the string one word at a time.
            for {} lt(subject, subjectEnd) {} {
                mstore(resultRemainder, mload(subject))
                resultRemainder := add(resultRemainder, 0x20)
                subject := add(subject, 0x20)
            }
            result := sub(result, 0x20)
            let last := add(add(result, 0x20), k) // Zeroize the slot after the string.
            mstore(last, 0)
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
            mstore(result, k) // Store the length.
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from left to right, starting from `from`.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function indexOf(string memory subject, string memory search, uint256 from)
        internal
        pure
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            for { let subjectLength := mload(subject) } 1 {} {
                if iszero(mload(search)) {
                    if iszero(gt(from, subjectLength)) {
                        result := from
                        break
                    }
                    result := subjectLength
                    break
                }
                let searchLength := mload(search)
                let subjectStart := add(subject, 0x20)

                result := not(0) // Initialize to `NOT_FOUND`.
                subject := add(subjectStart, from)
                let end := add(sub(add(subjectStart, subjectLength), searchLength), 1)

                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(add(search, 0x20))

                if iszero(and(lt(subject, end), lt(from, subjectLength))) { break }

                if iszero(lt(searchLength, 0x20)) {
                    for { let h := keccak256(add(search, 0x20), searchLength) } 1 {} {
                        if iszero(shr(m, xor(mload(subject), s))) {
                            if eq(keccak256(subject, searchLength), h) {
                                result := sub(subject, subjectStart)
                                break
                            }
                        }
                        subject := add(subject, 1)
                        if iszero(lt(subject, end)) { break }
                    }
                    break
                }
                for {} 1 {} {
                    if iszero(shr(m, xor(mload(subject), s))) {
                        result := sub(subject, subjectStart)
                        break
                    }
                    subject := add(subject, 1)
                    if iszero(lt(subject, end)) { break }
                }
                break
            }
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from left to right.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function indexOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256 result)
    {
        result = indexOf(subject, search, 0);
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from right to left, starting from `from`.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function lastIndexOf(string memory subject, string memory search, uint256 from)
        internal
        pure
        returns (uint256 result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            for {} 1 {} {
                result := not(0) // Initialize to `NOT_FOUND`.
                let searchLength := mload(search)
                if gt(searchLength, mload(subject)) { break }
                let w := result

                let fromMax := sub(mload(subject), searchLength)
                if iszero(gt(fromMax, from)) { from := fromMax }

                let end := add(add(subject, 0x20), w)
                subject := add(add(subject, 0x20), from)
                if iszero(gt(subject, end)) { break }
                // As this function is not too often used,
                // we shall simply use keccak256 for smaller bytecode size.
                for { let h := keccak256(add(search, 0x20), searchLength) } 1 {} {
                    if eq(keccak256(subject, searchLength), h) {
                        result := sub(subject, add(end, 1))
                        break
                    }
                    subject := add(subject, w) // `sub(subject, 1)`.
                    if iszero(gt(subject, end)) { break }
                }
                break
            }
        }
    }

    /// @dev Returns the byte index of the first location of `search` in `subject`,
    /// searching from right to left.
    /// Returns `NOT_FOUND` (i.e. `type(uint256).max`) if the `search` is not found.
    function lastIndexOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256 result)
    {
        result = lastIndexOf(subject, search, uint256(int256(-1)));
    }

    /// @dev Returns true if `search` is found in `subject`, false otherwise.
    function contains(string memory subject, string memory search) internal pure returns (bool) {
        return indexOf(subject, search) != NOT_FOUND;
    }

    /// @dev Returns whether `subject` starts with `search`.
    function startsWith(string memory subject, string memory search)
        internal
        pure
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let searchLength := mload(search)
            // Just using keccak256 directly is actually cheaper.
            // forgefmt: disable-next-item
            result := and(
                iszero(gt(searchLength, mload(subject))),
                eq(
                    keccak256(add(subject, 0x20), searchLength),
                    keccak256(add(search, 0x20), searchLength)
                )
            )
        }
    }

    /// @dev Returns whether `subject` ends with `search`.
    function endsWith(string memory subject, string memory search)
        internal
        pure
        returns (bool result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let searchLength := mload(search)
            let subjectLength := mload(subject)
            // Whether `search` is not longer than `subject`.
            let withinRange := iszero(gt(searchLength, subjectLength))
            // Just using keccak256 directly is actually cheaper.
            // forgefmt: disable-next-item
            result := and(
                withinRange,
                eq(
                    keccak256(
                        // `subject + 0x20 + max(subjectLength - searchLength, 0)`.
                        add(add(subject, 0x20), mul(withinRange, sub(subjectLength, searchLength))),
                        searchLength
                    ),
                    keccak256(add(search, 0x20), searchLength)
                )
            )
        }
    }

    /// @dev Returns `subject` repeated `times`.
    function repeat(string memory subject, uint256 times)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            if iszero(or(iszero(times), iszero(subjectLength))) {
                subject := add(subject, 0x20)
                result := mload(0x40)
                let output := add(result, 0x20)
                for {} 1 {} {
                    // Copy the `subject` one word at a time.
                    for { let o := 0 } 1 {} {
                        mstore(add(output, o), mload(add(subject, o)))
                        o := add(o, 0x20)
                        if iszero(lt(o, subjectLength)) { break }
                    }
                    output := add(output, subjectLength)
                    times := sub(times, 1)
                    if iszero(times) { break }
                }
                mstore(output, 0) // Zeroize the slot after the string.
                let resultLength := sub(output, add(result, 0x20))
                mstore(result, resultLength) // Store the length.
                mstore(0x40, add(result, add(resultLength, 0x40))) // Allocate the memory.
            }
        }
    }

    /// @dev Returns a copy of `subject` sliced from `start` to `end` (exclusive).
    /// `start` and `end` are byte offsets.
    function slice(string memory subject, uint256 start, uint256 end)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            if iszero(gt(subjectLength, end)) { end := subjectLength }
            if iszero(gt(subjectLength, start)) { start := subjectLength }
            if lt(start, end) {
                result := mload(0x40)
                let resultLength := sub(end, start)
                mstore(result, resultLength)
                subject := add(subject, start)
                let w := not(0x1f)
                // Copy the `subject` one word at a time, backwards.
                for { let o := and(add(resultLength, 0x1f), w) } 1 {} {
                    mstore(add(result, o), mload(add(subject, o)))
                    o := add(o, w) // `sub(o, 0x20)`.
                    if iszero(o) { break }
                }
                // Zeroize the slot after the string.
                mstore(add(add(result, 0x20), resultLength), 0)
                mstore(0x40, add(result, add(resultLength, 0x40))) // Allocate the memory.
            }
        }
    }

    /// @dev Returns a copy of `subject` sliced from `start` to the end of the string.
    /// `start` is a byte offset.
    function slice(string memory subject, uint256 start)
        internal
        pure
        returns (string memory result)
    {
        result = slice(subject, start, uint256(int256(-1)));
    }

    /// @dev Returns all the indices of `search` in `subject`.
    /// The indices are byte offsets.
    function indicesOf(string memory subject, string memory search)
        internal
        pure
        returns (uint256[] memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let subjectLength := mload(subject)
            let searchLength := mload(search)

            if iszero(gt(searchLength, subjectLength)) {
                subject := add(subject, 0x20)
                search := add(search, 0x20)
                result := add(mload(0x40), 0x20)

                let subjectStart := subject
                let subjectSearchEnd := add(sub(add(subject, subjectLength), searchLength), 1)
                let h := 0
                if iszero(lt(searchLength, 0x20)) { h := keccak256(search, searchLength) }
                let m := shl(3, sub(0x20, and(searchLength, 0x1f)))
                let s := mload(search)
                for {} 1 {} {
                    let t := mload(subject)
                    // Whether the first `searchLength % 32` bytes of
                    // `subject` and `search` matches.
                    if iszero(shr(m, xor(t, s))) {
                        if h {
                            if iszero(eq(keccak256(subject, searchLength), h)) {
                                subject := add(subject, 1)
                                if iszero(lt(subject, subjectSearchEnd)) { break }
                                continue
                            }
                        }
                        // Append to `result`.
                        mstore(result, sub(subject, subjectStart))
                        result := add(result, 0x20)
                        // Advance `subject` by `searchLength`.
                        subject := add(subject, searchLength)
                        if searchLength {
                            if iszero(lt(subject, subjectSearchEnd)) { break }
                            continue
                        }
                    }
                    subject := add(subject, 1)
                    if iszero(lt(subject, subjectSearchEnd)) { break }
                }
                let resultEnd := result
                // Assign `result` to the free memory pointer.
                result := mload(0x40)
                // Store the length of `result`.
                mstore(result, shr(5, sub(resultEnd, add(result, 0x20))))
                // Allocate memory for result.
                // We allocate one more word, so this array can be recycled for {split}.
                mstore(0x40, add(resultEnd, 0x20))
            }
        }
    }

    /// @dev Returns a arrays of strings based on the `delimiter` inside of the `subject` string.
    function split(string memory subject, string memory delimiter)
        internal
        pure
        returns (string[] memory result)
    {
        uint256[] memory indices = indicesOf(subject, delimiter);
        /// @solidity memory-safe-assembly
        assembly {
            let w := not(0x1f)
            let indexPtr := add(indices, 0x20)
            let indicesEnd := add(indexPtr, shl(5, add(mload(indices), 1)))
            mstore(add(indicesEnd, w), mload(subject))
            mstore(indices, add(mload(indices), 1))
            let prevIndex := 0
            for {} 1 {} {
                let index := mload(indexPtr)
                mstore(indexPtr, 0x60)
                if iszero(eq(index, prevIndex)) {
                    let element := mload(0x40)
                    let elementLength := sub(index, prevIndex)
                    mstore(element, elementLength)
                    // Copy the `subject` one word at a time, backwards.
                    for { let o := and(add(elementLength, 0x1f), w) } 1 {} {
                        mstore(add(element, o), mload(add(add(subject, prevIndex), o)))
                        o := add(o, w) // `sub(o, 0x20)`.
                        if iszero(o) { break }
                    }
                    // Zeroize the slot after the string.
                    mstore(add(add(element, 0x20), elementLength), 0)
                    // Allocate memory for the length and the bytes,
                    // rounded up to a multiple of 32.
                    mstore(0x40, add(element, and(add(elementLength, 0x3f), w)))
                    // Store the `element` into the array.
                    mstore(indexPtr, element)
                }
                prevIndex := add(index, mload(delimiter))
                indexPtr := add(indexPtr, 0x20)
                if iszero(lt(indexPtr, indicesEnd)) { break }
            }
            result := indices
            if iszero(mload(delimiter)) {
                result := add(indices, 0x20)
                mstore(result, sub(mload(indices), 2))
            }
        }
    }

    /// @dev Returns a concatenated string of `a` and `b`.
    /// Cheaper than `string.concat()` and does not de-align the free memory pointer.
    function concat(string memory a, string memory b)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let w := not(0x1f)
            result := mload(0x40)
            let aLength := mload(a)
            // Copy `a` one word at a time, backwards.
            for { let o := and(add(aLength, 0x20), w) } 1 {} {
                mstore(add(result, o), mload(add(a, o)))
                o := add(o, w) // `sub(o, 0x20)`.
                if iszero(o) { break }
            }
            let bLength := mload(b)
            let output := add(result, aLength)
            // Copy `b` one word at a time, backwards.
            for { let o := and(add(bLength, 0x20), w) } 1 {} {
                mstore(add(output, o), mload(add(b, o)))
                o := add(o, w) // `sub(o, 0x20)`.
                if iszero(o) { break }
            }
            let totalLength := add(aLength, bLength)
            let last := add(add(result, 0x20), totalLength)
            mstore(last, 0) // Zeroize the slot after the string.
            mstore(result, totalLength) // Store the length.
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
        }
    }

    /// @dev Returns a copy of the string in either lowercase or UPPERCASE.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function toCase(string memory subject, bool toUpper)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let length := mload(subject)
            if length {
                result := add(mload(0x40), 0x20)
                subject := add(subject, 1)
                let flags := shl(add(70, shl(5, toUpper)), 0x3ffffff)
                let w := not(0)
                for { let o := length } 1 {} {
                    o := add(o, w)
                    let b := and(0xff, mload(add(subject, o)))
                    mstore8(add(result, o), xor(b, and(shr(b, flags), 0x20)))
                    if iszero(o) { break }
                }
                result := mload(0x40)
                mstore(result, length) // Store the length.
                let last := add(add(result, 0x20), length)
                mstore(last, 0) // Zeroize the slot after the string.
                mstore(0x40, add(last, 0x20)) // Allocate the memory.
            }
        }
    }

    /// @dev Returns a string from a small bytes32 string.
    /// `s` must be null-terminated, or behavior will be undefined.
    function fromSmallString(bytes32 s) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40)
            let n := 0
            for {} byte(n, s) { n := add(n, 1) } {} // Scan for '\0'.
            mstore(result, n) // Store the length.
            let o := add(result, 0x20)
            mstore(o, s) // Store the bytes of the string.
            mstore(add(o, n), 0) // Zeroize the slot after the string.
            mstore(0x40, add(result, 0x40)) // Allocate the memory.
        }
    }

    /// @dev Returns the small string, with all bytes after the first null byte zeroized.
    function normalizeSmallString(bytes32 s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            for {} byte(result, s) { result := add(result, 1) } {} // Scan for '\0'.
            mstore(0x00, s)
            mstore(result, 0x00)
            result := mload(0x00)
        }
    }

    /// @dev Returns the string as a normalized null-terminated small string.
    function toSmallString(string memory s) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(s)
            if iszero(lt(result, 33)) {
                mstore(0x00, 0xec92f9a3) // `TooBigForSmallString()`.
                revert(0x1c, 0x04)
            }
            result := shl(shl(3, sub(32, result)), mload(add(s, result)))
        }
    }

    /// @dev Returns a lowercased copy of the string.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function lower(string memory subject) internal pure returns (string memory result) {
        result = toCase(subject, false);
    }

    /// @dev Returns an UPPERCASED copy of the string.
    /// WARNING! This function is only compatible with 7-bit ASCII strings.
    function upper(string memory subject) internal pure returns (string memory result) {
        result = toCase(subject, true);
    }

    /// @dev Escapes the string to be used within HTML tags.
    function escapeHTML(string memory s) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            let end := add(s, mload(s))
            result := add(mload(0x40), 0x20)
            // Store the bytes of the packed offsets and strides into the scratch space.
            // `packed = (stride << 5) | offset`. Max offset is 20. Max stride is 6.
            mstore(0x1f, 0x900094)
            mstore(0x08, 0xc0000000a6ab)
            // Store "&quot;&amp;&#39;&lt;&gt;" into the scratch space.
            mstore(0x00, shl(64, 0x2671756f743b26616d703b262333393b266c743b2667743b))
            for {} iszero(eq(s, end)) {} {
                s := add(s, 1)
                let c := and(mload(s), 0xff)
                // Not in `["\"","'","&","<",">"]`.
                if iszero(and(shl(c, 1), 0x500000c400000000)) {
                    mstore8(result, c)
                    result := add(result, 1)
                    continue
                }
                let t := shr(248, mload(c))
                mstore(result, mload(and(t, 0x1f)))
                result := add(result, shr(5, t))
            }
            let last := result
            mstore(last, 0) // Zeroize the slot after the string.
            result := mload(0x40)
            mstore(result, sub(last, add(result, 0x20))) // Store the length.
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
        }
    }

    /// @dev Escapes the string to be used within double-quotes in a JSON.
    /// If `addDoubleQuotes` is true, the result will be enclosed in double-quotes.
    function escapeJSON(string memory s, bool addDoubleQuotes)
        internal
        pure
        returns (string memory result)
    {
        /// @solidity memory-safe-assembly
        assembly {
            let end := add(s, mload(s))
            result := add(mload(0x40), 0x20)
            if addDoubleQuotes {
                mstore8(result, 34)
                result := add(1, result)
            }
            // Store "\\u0000" in scratch space.
            // Store "0123456789abcdef" in scratch space.
            // Also, store `{0x08:"b", 0x09:"t", 0x0a:"n", 0x0c:"f", 0x0d:"r"}`.
            // into the scratch space.
            mstore(0x15, 0x5c75303030303031323334353637383961626364656662746e006672)
            // Bitmask for detecting `["\"","\\"]`.
            let e := or(shl(0x22, 1), shl(0x5c, 1))
            for {} iszero(eq(s, end)) {} {
                s := add(s, 1)
                let c := and(mload(s), 0xff)
                if iszero(lt(c, 0x20)) {
                    if iszero(and(shl(c, 1), e)) {
                        // Not in `["\"","\\"]`.
                        mstore8(result, c)
                        result := add(result, 1)
                        continue
                    }
                    mstore8(result, 0x5c) // "\\".
                    mstore8(add(result, 1), c)
                    result := add(result, 2)
                    continue
                }
                if iszero(and(shl(c, 1), 0x3700)) {
                    // Not in `["\b","\t","\n","\f","\d"]`.
                    mstore8(0x1d, mload(shr(4, c))) // Hex value.
                    mstore8(0x1e, mload(and(c, 15))) // Hex value.
                    mstore(result, mload(0x19)) // "\\u00XX".
                    result := add(result, 6)
                    continue
                }
                mstore8(result, 0x5c) // "\\".
                mstore8(add(result, 1), mload(add(c, 8)))
                result := add(result, 2)
            }
            if addDoubleQuotes {
                mstore8(result, 34)
                result := add(1, result)
            }
            let last := result
            mstore(last, 0) // Zeroize the slot after the string.
            result := mload(0x40)
            mstore(result, sub(last, add(result, 0x20))) // Store the length.
            mstore(0x40, add(last, 0x20)) // Allocate the memory.
        }
    }

    /// @dev Escapes the string to be used within double-quotes in a JSON.
    function escapeJSON(string memory s) internal pure returns (string memory result) {
        result = escapeJSON(s, false);
    }

    /// @dev Returns whether `a` equals `b`.
    function eq(string memory a, string memory b) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := eq(keccak256(add(a, 0x20), mload(a)), keccak256(add(b, 0x20), mload(b)))
        }
    }

    /// @dev Returns whether `a` equals `b`, where `b` is a null-terminated small string.
    function eqs(string memory a, bytes32 b) internal pure returns (bool result) {
        /// @solidity memory-safe-assembly
        assembly {
            // These should be evaluated on compile time, as far as possible.
            let m := not(shl(7, div(not(iszero(b)), 255))) // `0x7f7f ...`.
            let x := not(or(m, or(b, add(m, and(b, m)))))
            let r := shl(7, iszero(iszero(shr(128, x))))
            r := or(r, shl(6, iszero(iszero(shr(64, shr(r, x))))))
            r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
            r := or(r, shl(4, lt(0xffff, shr(r, x))))
            r := or(r, shl(3, lt(0xff, shr(r, x))))
            // forgefmt: disable-next-item
            result := gt(eq(mload(a), add(iszero(x), xor(31, shr(3, r)))),
                xor(shr(add(8, r), b), shr(add(8, r), mload(add(a, 0x20)))))
        }
    }

    /// @dev Packs a single string with its length into a single word.
    /// Returns `bytes32(0)` if the length is zero or greater than 31.
    function packOne(string memory a) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            // We don't need to zero right pad the string,
            // since this is our own custom non-standard packing scheme.
            result :=
                mul(
                    // Load the length and the bytes.
                    mload(add(a, 0x1f)),
                    // `length != 0 && length < 32`. Abuses underflow.
                    // Assumes that the length is valid and within the block gas limit.
                    lt(sub(mload(a), 1), 0x1f)
                )
        }
    }

    /// @dev Unpacks a string packed using {packOne}.
    /// Returns the empty string if `packed` is `bytes32(0)`.
    /// If `packed` is not an output of {packOne}, the output behavior is undefined.
    function unpackOne(bytes32 packed) internal pure returns (string memory result) {
        /// @solidity memory-safe-assembly
        assembly {
            result := mload(0x40) // Grab the free memory pointer.
            mstore(0x40, add(result, 0x40)) // Allocate 2 words (1 for the length, 1 for the bytes).
            mstore(result, 0) // Zeroize the length slot.
            mstore(add(result, 0x1f), packed) // Store the length and bytes.
            mstore(add(add(result, 0x20), mload(result)), 0) // Right pad with zeroes.
        }
    }

    /// @dev Packs two strings with their lengths into a single word.
    /// Returns `bytes32(0)` if combined length is zero or greater than 30.
    function packTwo(string memory a, string memory b) internal pure returns (bytes32 result) {
        /// @solidity memory-safe-assembly
        assembly {
            let aLength := mload(a)
            // We don't need to zero right pad the strings,
            // since this is our own custom non-standard packing scheme.
            result :=
                mul(
                    or( // Load the length and the bytes of `a` and `b`.
                        shl(shl(3, sub(0x1f, aLength)), mload(add(a, aLength))),
                        mload(sub(add(b, 0x1e), aLength))
                    ),
                    // `totalLength != 0 && totalLength < 31`. Abuses underflow.
                    // Assumes that the lengths are valid and within the block gas limit.
                    lt(sub(add(aLength, mload(b)), 1), 0x1e)
                )
        }
    }

    /// @dev Unpacks strings packed using {packTwo}.
    /// Returns the empty strings if `packed` is `bytes32(0)`.
    /// If `packed` is not an output of {packTwo}, the output behavior is undefined.
    function unpackTwo(bytes32 packed)
        internal
        pure
        returns (string memory resultA, string memory resultB)
    {
        /// @solidity memory-safe-assembly
        assembly {
            resultA := mload(0x40) // Grab the free memory pointer.
            resultB := add(resultA, 0x40)
            // Allocate 2 words for each string (1 for the length, 1 for the byte). Total 4 words.
            mstore(0x40, add(resultB, 0x40))
            // Zeroize the length slots.
            mstore(resultA, 0)
            mstore(resultB, 0)
            // Store the lengths and bytes.
            mstore(add(resultA, 0x1f), packed)
            mstore(add(resultB, 0x1f), mload(add(add(resultA, 0x20), mload(resultA))))
            // Right pad with zeroes.
            mstore(add(add(resultA, 0x20), mload(resultA)), 0)
            mstore(add(add(resultB, 0x20), mload(resultB)), 0)
        }
    }

    /// @dev Directly returns `a` without copying.
    function directReturn(string memory a) internal pure {
        assembly {
            // Assumes that the string does not start from the scratch space.
            let retStart := sub(a, 0x20)
            let retUnpaddedSize := add(mload(a), 0x40)
            // Right pad with zeroes. Just in case the string is produced
            // by a method that doesn't zero right pad.
            mstore(add(retStart, retUnpaddedSize), 0)
            mstore(retStart, 0x20) // Store the return offset.
            // End the transaction, returning the string.
            return(retStart, and(not(0x1f), add(0x1f, retUnpaddedSize)))
        }
    }
}