Contract Source Code:

// SPDX-License-Identifier: BUSL-1.1

pragma solidity 0.8.24;

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

import "./Interfaces/ITroveManager.sol";
import "./Interfaces/IBoldToken.sol";
import "./Dependencies/Constants.sol";
import "./Dependencies/LiquityMath.sol";

import "./Interfaces/ICollateralRegistry.sol";

contract CollateralRegistry is ICollateralRegistry {
    // See: https://github.com/ethereum/solidity/issues/12587
    uint256 public immutable totalCollaterals;

    IERC20Metadata internal immutable token0;
    IERC20Metadata internal immutable token1;
    IERC20Metadata internal immutable token2;
    IERC20Metadata internal immutable token3;
    IERC20Metadata internal immutable token4;
    IERC20Metadata internal immutable token5;
    IERC20Metadata internal immutable token6;
    IERC20Metadata internal immutable token7;
    IERC20Metadata internal immutable token8;
    IERC20Metadata internal immutable token9;

    ITroveManager internal immutable troveManager0;
    ITroveManager internal immutable troveManager1;
    ITroveManager internal immutable troveManager2;
    ITroveManager internal immutable troveManager3;
    ITroveManager internal immutable troveManager4;
    ITroveManager internal immutable troveManager5;
    ITroveManager internal immutable troveManager6;
    ITroveManager internal immutable troveManager7;
    ITroveManager internal immutable troveManager8;
    ITroveManager internal immutable troveManager9;

    IBoldToken public immutable boldToken;

    uint256 public baseRate;

    // The timestamp of the latest fee operation (redemption or new Bold issuance)
    uint256 public lastFeeOperationTime = block.timestamp;

    event BaseRateUpdated(uint256 _baseRate);
    event LastFeeOpTimeUpdated(uint256 _lastFeeOpTime);

    constructor(IBoldToken _boldToken, IERC20Metadata[] memory _tokens, ITroveManager[] memory _troveManagers) {
        uint256 numTokens = _tokens.length;
        require(numTokens > 0, "Collateral list cannot be empty");
        require(numTokens <= 10, "Collateral list too long");
        totalCollaterals = numTokens;

        boldToken = _boldToken;

        token0 = _tokens[0];
        token1 = numTokens > 1 ? _tokens[1] : IERC20Metadata(address(0));
        token2 = numTokens > 2 ? _tokens[2] : IERC20Metadata(address(0));
        token3 = numTokens > 3 ? _tokens[3] : IERC20Metadata(address(0));
        token4 = numTokens > 4 ? _tokens[4] : IERC20Metadata(address(0));
        token5 = numTokens > 5 ? _tokens[5] : IERC20Metadata(address(0));
        token6 = numTokens > 6 ? _tokens[6] : IERC20Metadata(address(0));
        token7 = numTokens > 7 ? _tokens[7] : IERC20Metadata(address(0));
        token8 = numTokens > 8 ? _tokens[8] : IERC20Metadata(address(0));
        token9 = numTokens > 9 ? _tokens[9] : IERC20Metadata(address(0));

        troveManager0 = _troveManagers[0];
        troveManager1 = numTokens > 1 ? _troveManagers[1] : ITroveManager(address(0));
        troveManager2 = numTokens > 2 ? _troveManagers[2] : ITroveManager(address(0));
        troveManager3 = numTokens > 3 ? _troveManagers[3] : ITroveManager(address(0));
        troveManager4 = numTokens > 4 ? _troveManagers[4] : ITroveManager(address(0));
        troveManager5 = numTokens > 5 ? _troveManagers[5] : ITroveManager(address(0));
        troveManager6 = numTokens > 6 ? _troveManagers[6] : ITroveManager(address(0));
        troveManager7 = numTokens > 7 ? _troveManagers[7] : ITroveManager(address(0));
        troveManager8 = numTokens > 8 ? _troveManagers[8] : ITroveManager(address(0));
        troveManager9 = numTokens > 9 ? _troveManagers[9] : ITroveManager(address(0));

        // Initialize the baseRate state variable
        baseRate = INITIAL_BASE_RATE;
        emit BaseRateUpdated(INITIAL_BASE_RATE);
    }

    struct RedemptionTotals {
        uint256 numCollaterals;
        uint256 boldSupplyAtStart;
        uint256 unbacked;
        uint256 redeemedAmount;
    }

    function redeemCollateral(uint256 _boldAmount, uint256 _maxIterationsPerCollateral, uint256 _maxFeePercentage)
        external
    {
        _requireValidMaxFeePercentage(_maxFeePercentage);
        _requireAmountGreaterThanZero(_boldAmount);

        RedemptionTotals memory totals;

        totals.numCollaterals = totalCollaterals;
        uint256[] memory unbackedPortions = new uint256[](totals.numCollaterals);
        uint256[] memory prices = new uint256[](totals.numCollaterals);

        totals.boldSupplyAtStart = boldToken.totalSupply();
        // Decay the baseRate due to time passed, and then increase it according to the size of this redemption.
        // Use the saved total Bold supply value, from before it was reduced by the redemption.
        // We only compute it here, and update it at the end,
        // because the final redeemed amount may be less than the requested amount
        // Redeemers should take this into account in order to request the optimal amount to not overpay
        uint256 redemptionRate =
            _calcRedemptionRate(_getUpdatedBaseRateFromRedemption(_boldAmount, totals.boldSupplyAtStart));
        require(redemptionRate <= _maxFeePercentage, "CR: Fee exceeded provided maximum");
        // Implicit by the above and the _requireValidMaxFeePercentage checks
        //require(newBaseRate < DECIMAL_PRECISION, "CR: Fee would eat up all collateral");

        // Gather and accumulate unbacked portions
        for (uint256 index = 0; index < totals.numCollaterals; index++) {
            ITroveManager troveManager = getTroveManager(index);
            (uint256 unbackedPortion, uint256 price, bool redeemable) =
                troveManager.getUnbackedPortionPriceAndRedeemability();
            prices[index] = price;
            if (redeemable) {
                totals.unbacked += unbackedPortion;
                unbackedPortions[index] = unbackedPortion;
            }
        }

        // There’s an unlikely scenario where all the normally redeemable branches (i.e. having TCR > SCR) have 0 unbacked
        // In that case, we redeem proportinally to branch size
        if (totals.unbacked == 0) {
            unbackedPortions = new uint256[](totals.numCollaterals);
            for (uint256 index = 0; index < totals.numCollaterals; index++) {
                ITroveManager troveManager = getTroveManager(index);
                (,, bool redeemable) = troveManager.getUnbackedPortionPriceAndRedeemability();
                if (redeemable) {
                    uint256 unbackedPortion = troveManager.getEntireSystemDebt();
                    totals.unbacked += unbackedPortion;
                    unbackedPortions[index] = unbackedPortion;
                }
            }
        }

        // Compute redemption amount for each collateral and redeem against the corresponding TroveManager
        for (uint256 index = 0; index < totals.numCollaterals; index++) {
            //uint256 unbackedPortion = unbackedPortions[index];
            if (unbackedPortions[index] > 0) {
                uint256 redeemAmount = _boldAmount * unbackedPortions[index] / totals.unbacked;
                if (redeemAmount > 0) {
                    ITroveManager troveManager = getTroveManager(index);
                    uint256 redeemedAmount = troveManager.redeemCollateral(
                        msg.sender, redeemAmount, prices[index], redemptionRate, _maxIterationsPerCollateral
                    );
                    totals.redeemedAmount += redeemedAmount;
                }
            }
        }

        _updateBaseRateAndGetRedemptionRate(totals.redeemedAmount, totals.boldSupplyAtStart);

        // Burn the total Bold that is cancelled with debt
        if (totals.redeemedAmount > 0) {
            boldToken.burn(msg.sender, totals.redeemedAmount);
        }
    }

    // --- Internal fee functions ---

    // Update the last fee operation time only if time passed >= decay interval. This prevents base rate griefing.
    function _updateLastFeeOpTime() internal {
        uint256 timePassed = block.timestamp - lastFeeOperationTime;

        if (timePassed >= ONE_MINUTE) {
            lastFeeOperationTime = block.timestamp;
            emit LastFeeOpTimeUpdated(block.timestamp);
        }
    }

    function _minutesPassedSinceLastFeeOp() internal view returns (uint256) {
        return (block.timestamp - lastFeeOperationTime) / ONE_MINUTE;
    }

    // Updates the `baseRate` state with math from `_getUpdatedBaseRateFromRedemption`
    function _updateBaseRateAndGetRedemptionRate(uint256 _boldAmount, uint256 _totalBoldSupplyAtStart) internal {
        uint256 newBaseRate = _getUpdatedBaseRateFromRedemption(_boldAmount, _totalBoldSupplyAtStart);

        //assert(newBaseRate <= DECIMAL_PRECISION); // This is already enforced in `_getUpdatedBaseRateFromRedemption`

        // Update the baseRate state variable
        baseRate = newBaseRate;
        emit BaseRateUpdated(newBaseRate);

        _updateLastFeeOpTime();
    }

    /*
     * This function calculates the new baseRate in the following way:
     * 1) decays the baseRate based on time passed since last redemption or Bold borrowing operation.
     * then,
     * 2) increases the baseRate based on the amount redeemed, as a proportion of total supply
     */
    function _getUpdatedBaseRateFromRedemption(uint256 _redeemAmount, uint256 _totalBoldSupply)
        internal
        view
        returns (uint256)
    {
        // decay the base rate
        uint256 decayedBaseRate = _calcDecayedBaseRate();

        // get the fraction of total supply that was redeemed
        uint256 redeemedBoldFraction = _redeemAmount * DECIMAL_PRECISION / _totalBoldSupply;

        uint256 newBaseRate = decayedBaseRate + redeemedBoldFraction / REDEMPTION_BETA;
        newBaseRate = LiquityMath._min(newBaseRate, DECIMAL_PRECISION); // cap baseRate at a maximum of 100%

        return newBaseRate;
    }

    function _calcDecayedBaseRate() internal view returns (uint256) {
        uint256 minutesPassed = _minutesPassedSinceLastFeeOp();
        uint256 decayFactor = LiquityMath._decPow(REDEMPTION_MINUTE_DECAY_FACTOR, minutesPassed);

        return baseRate * decayFactor / DECIMAL_PRECISION;
    }

    function _calcRedemptionRate(uint256 _baseRate) internal pure returns (uint256) {
        return LiquityMath._min(
            REDEMPTION_FEE_FLOOR + _baseRate,
            DECIMAL_PRECISION // cap at a maximum of 100%
        );
    }

    function _calcRedemptionFee(uint256 _redemptionRate, uint256 _amount) internal pure returns (uint256) {
        uint256 redemptionFee = _redemptionRate * _amount / DECIMAL_PRECISION;
        return redemptionFee;
    }

    // external redemption rate/fee getters

    function getRedemptionRate() external view override returns (uint256) {
        return _calcRedemptionRate(baseRate);
    }

    function getRedemptionRateWithDecay() public view override returns (uint256) {
        return _calcRedemptionRate(_calcDecayedBaseRate());
    }

    function getRedemptionRateForRedeemedAmount(uint256 _redeemAmount) external view returns (uint256) {
        uint256 totalBoldSupply = boldToken.totalSupply();
        uint256 newBaseRate = _getUpdatedBaseRateFromRedemption(_redeemAmount, totalBoldSupply);
        return _calcRedemptionRate(newBaseRate);
    }

    function getRedemptionFeeWithDecay(uint256 _ETHDrawn) external view override returns (uint256) {
        return _calcRedemptionFee(getRedemptionRateWithDecay(), _ETHDrawn);
    }

    function getEffectiveRedemptionFeeInBold(uint256 _redeemAmount) external view override returns (uint256) {
        uint256 totalBoldSupply = boldToken.totalSupply();
        uint256 newBaseRate = _getUpdatedBaseRateFromRedemption(_redeemAmount, totalBoldSupply);
        return _calcRedemptionFee(_calcRedemptionRate(newBaseRate), _redeemAmount);
    }

    // getters

    function getToken(uint256 _index) external view returns (IERC20Metadata) {
        if (_index == 0) return token0;
        else if (_index == 1) return token1;
        else if (_index == 2) return token2;
        else if (_index == 3) return token3;
        else if (_index == 4) return token4;
        else if (_index == 5) return token5;
        else if (_index == 6) return token6;
        else if (_index == 7) return token7;
        else if (_index == 8) return token8;
        else if (_index == 9) return token9;
        else revert("Invalid index");
    }

    function getTroveManager(uint256 _index) public view returns (ITroveManager) {
        if (_index == 0) return troveManager0;
        else if (_index == 1) return troveManager1;
        else if (_index == 2) return troveManager2;
        else if (_index == 3) return troveManager3;
        else if (_index == 4) return troveManager4;
        else if (_index == 5) return troveManager5;
        else if (_index == 6) return troveManager6;
        else if (_index == 7) return troveManager7;
        else if (_index == 8) return troveManager8;
        else if (_index == 9) return troveManager9;
        else revert("Invalid index");
    }

    // require functions

    function _requireValidMaxFeePercentage(uint256 _maxFeePercentage) internal pure {
        require(
            _maxFeePercentage >= REDEMPTION_FEE_FLOOR && _maxFeePercentage <= DECIMAL_PRECISION,
            "Max fee percentage must be between 0.5% and 100%"
        );
    }

    function _requireAmountGreaterThanZero(uint256 _amount) internal pure {
        require(_amount > 0, "CollateralRegistry: Amount must be greater than zero");
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.20;

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

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

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

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

// SPDX-License-Identifier: MIT

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 {IERC20Metadata} from "openzeppelin-contracts/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import {IERC5267} from "openzeppelin-contracts/contracts/interfaces/IERC5267.sol";

interface IBoldToken is IERC20Metadata, 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: 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;

// 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 = _100pct;

// Batch management params
uint128 constant MAX_ANNUAL_BATCH_MANAGEMENT_FEE = uint128(_100pct);
uint128 constant MIN_INTEREST_RATE_CHANGE_PERIOD = 1 seconds; // prevents more than one adjustment per block

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 12h. 12h = 720 min
// (1/2) = d^720 => d = (1/2)^(1/720)
uint256 constant REDEMPTION_MINUTE_DECAY_FACTOR = 999037758833783000;

// 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 = 2;

// To prevent redemptions unless Bold depegs below 0.95 and allow the system to take off
uint256 constant INITIAL_BASE_RATE = 5 * _1pct - REDEMPTION_FEE_FLOOR; // 5% initial redemption rate

// Discount to be used once the shutdown thas been triggered
uint256 constant URGENT_REDEMPTION_BONUS = 1e16; // 1%

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 = 3 days;

uint256 constant SP_YIELD_SPLIT = 72 * _1pct; // 72%

// 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 {DECIMAL_PRECISION} from "./Constants.sol";

library LiquityMath {
    function _min(uint256 _a, uint256 _b) internal pure returns (uint256) {
        return (_a < _b) ? _a : _b;
    }

    function _max(uint256 _a, uint256 _b) internal pure returns (uint256) {
        return (_a >= _b) ? _a : _b;
    }

    function _sub_min_0(uint256 _a, uint256 _b) internal pure returns (uint256) {
        return (_a > _b) ? _a - _b : 0;
    }

    /* 
    * Multiply two decimal numbers and use normal rounding rules:
    * -round product up if 19'th mantissa digit >= 5
    * -round product down if 19'th mantissa digit < 5
    *
    * Used only inside the exponentiation, _decPow().
    */
    function decMul(uint256 x, uint256 y) internal pure returns (uint256 decProd) {
        uint256 prod_xy = x * y;

        decProd = (prod_xy + DECIMAL_PRECISION / 2) / DECIMAL_PRECISION;
    }

    /* 
    * _decPow: Exponentiation function for 18-digit decimal base, and integer exponent n.
    * 
    * Uses the efficient "exponentiation by squaring" algorithm. O(log(n)) complexity. 
    * 
    * Called by function CollateralRegistry._calcDecayedBaseRate, that represent time in units of minutes
    *
    * The exponent is capped to avoid reverting due to overflow. The cap 525600000 equals
    * "minutes in 1000 years": 60 * 24 * 365 * 1000
    * 
    * If a period of > 1000 years is ever used as an exponent in either of the above functions, the result will be
    * negligibly different from just passing the cap, since: 
    *
    * In function 1), the decayed base rate will be 0 for 1000 years or > 1000 years
    * In function 2), the difference in tokens issued at 1000 years and any time > 1000 years, will be negligible
    */
    function _decPow(uint256 _base, uint256 _minutes) internal pure returns (uint256) {
        if (_minutes > 525600000) _minutes = 525600000; // cap to avoid overflow

        if (_minutes == 0) return DECIMAL_PRECISION;

        uint256 y = DECIMAL_PRECISION;
        uint256 x = _base;
        uint256 n = _minutes;

        // Exponentiation-by-squaring
        while (n > 1) {
            if (n % 2 == 0) {
                x = decMul(x, x);
                n = n / 2;
            } else {
                // if (n % 2 != 0)
                y = decMul(x, y);
                x = decMul(x, x);
                n = (n - 1) / 2;
            }
        }

        return decMul(x, y);
    }

    function _getAbsoluteDifference(uint256 _a, uint256 _b) internal pure returns (uint256) {
        return (_a >= _b) ? _a - _b : _b - _a;
    }

    function _computeCR(uint256 _coll, uint256 _debt, uint256 _price) internal pure returns (uint256) {
        if (_debt > 0) {
            uint256 newCollRatio = _coll * _price / _debt;

            return newCollRatio;
        }
        // Return the maximal value for uint256 if the debt is 0. Represents "infinite" CR.
        else {
            // if (_debt == 0)
            return 2 ** 256 - 1;
        }
    }
}

// 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
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.20;

/**
 * @dev Interface of the ERC-20 standard as defined in the ERC.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

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

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

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

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

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

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

// SPDX-License-Identifier: MIT

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;

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 "./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;

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 "./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 0.8.24;

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 0.8.24;

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
// OpenZeppelin Contracts (last updated v5.0.0) (interfaces/IERC5267.sol)

pragma solidity ^0.8.20;

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

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 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

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
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC721/extensions/IERC721Metadata.sol)

pragma solidity ^0.8.20;

import {IERC721} from "../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 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 "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 ^0.8.0;

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

// 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: MIT

pragma solidity ^0.8.0;

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

// SPDX-License-Identifier: MIT

pragma solidity 0.8.24;

struct TroveChange {
    uint256 appliedRedistBoldDebtGain;
    uint256 appliedRedistCollGain;
    uint256 collIncrease;
    uint256 collDecrease;
    uint256 debtIncrease;
    uint256 debtDecrease;
    uint256 newWeightedRecordedDebt;
    uint256 oldWeightedRecordedDebt;
    uint256 upfrontFee;
    uint256 batchAccruedManagementFee;
    uint256 newWeightedRecordedBatchManagementFee;
    uint256 oldWeightedRecordedBatchManagementFee;
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC721/IERC721.sol)

pragma solidity ^0.8.20;

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

/**
 * @dev Required interface of an ERC-721 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 ERC-721 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 ERC-721
     * 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 address zero.
     *
     * 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 (last updated v5.1.0) (utils/introspection/IERC165.sol)

pragma solidity ^0.8.20;

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