> For the complete documentation index, see [llms.txt](https://docs.fluidnft.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fluidnft.org/technical-resources/developers/contract-reference/stable-debt-tokens/ivariabledebttoken.md).

# IVariableDebtToken

{% tabs %}
{% tab title="IVariableDebtToken.sol" %}

```solidity
// SPDX-License-Identifier: AGPL-3.0
pragma solidity 0.8.16;

import {IAddressProvider} from "../interfaces/IAddressProvider.sol";
import {IPoolIncentivesController} from "./IPoolIncentivesController.sol";
import {IScaledBalanceToken} from "./IScaledBalanceToken.sol";


import {IERC20Upgradeable} from "@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol";
import {IERC20MetadataUpgradeable} from "@openzeppelin/contracts-upgradeable/token/ERC20/extensions/IERC20MetadataUpgradeable.sol";


interface IVariableDebtToken is IScaledBalanceToken, IERC20Upgradeable, IERC20MetadataUpgradeable {
    /**
    * @dev Emitted when a debt token is initialized
    * @param underlyingCollateral The address of the underlying collateral
    * @param underlyingAsset The address of the underlying asset
    * @param pool The address of the associated lend pool
    * @param incentivesController The address of the incentives controller
    * @param debtTokenDecimals the decimals of the debt token
    * @param debtTokenName the name of the debt token
    * @param debtTokenSymbol the symbol of the debt token
    **/
    event Initialized(
        address indexed underlyingCollateral,
        address indexed underlyingAsset,
        address indexed pool,
        address incentivesController,
        uint8 debtTokenDecimals,
        string debtTokenName,
        string debtTokenSymbol
    );

    /**
    * @dev Emitted after the mint action
    * @param from The address performing the mint
    * @param value The amount to be minted
    * @param index The last index of the reserve
    **/
    event Mint(address indexed from, uint256 value, uint256 index);

    /**
    * @dev Emitted when variable debt is burnt
    * @param user The user which debt has been burned
    * @param amount The amount of debt being burned
    * @param index The index of the user
    **/
    event Burn(address indexed user, uint256 amount, uint256 index);

    function initialize(
        address addressProvider,
        address underlyingCollateral,
        address underlyingAsset,
        uint256 underlyingMaxTokenId,
        uint256 underlyingMinTokenId,
        uint8 debtTokenDecimals,
        string memory debtTokenName,
        string memory debtTokenSymbol
    ) external;
    
    function mint(
        address user,
        address onBehalfOf,
        uint256 amount,
        uint256 index
    ) external returns (bool);

    function burn(
        address user,
        uint256 amount,
        uint256 index
    ) external returns (bool);

    function getPoolIncentivesController() external view returns (IPoolIncentivesController);

    function scaledTotalSupply() external view returns (uint256);
}
```

{% endtab %}

{% tab title="IAddressProvider.sol" %}

```solidity
// SPDX-License-Identifier: AGPL-3.0
pragma solidity 0.8.16;

/**
 * @title AddressProvider contract
 * @dev Main registry of addresses part of or connected to the protocol, including permissioned roles
 * - Acting also as factory of proxies and admin of those, so with right to change its implementations
 * - Owned by the FluidNFT Governance
 * @author FluidNFT
 **/
interface IAddressProvider {
    event MarketIdSet(string newMarketId);
    event AddressSet(bytes32 id, address indexed newAddress, bool hasProxy);
    event ExecutionDelegateUpdated(address indexed newAddress);
    event ExecutionManagerUpdated(address indexed newAddress);
    event LendingUpdated(address indexed newAddress);
    event PromissoryNoteUpdated(address indexed newAddress);
    event PromissoryNoteBundleUpdated(address indexed newAddress);
    event ObligationReceiptUpdated(address indexed newAddress);
    event ObligationReceiptBundleUpdated(address indexed newAddress);
    event LendingPoolUpdated(address indexed newAddress);
    event ConfiguratorUpdated(address indexed newAddress);
    event CollateralManagerUpdated(address indexed newAddress);
    event PeerAdminUpdated(address indexed newAddress);
    event PoolAdminUpdated(address indexed newAddress);
    event EmergencyAdminUpdated(address indexed newAddress);
    event PriceConsumerUpdated(address indexed newAddress);
    event FluidTokenUpdated(address indexed newAddress);
    event PoolIncentivesControllerUpdated(address indexed newAddress);
    event PeerIncentivesControllerUpdated(address indexed newAddress);
    event ReferralManagerUpdated(address indexed newAddress);
    event TreasuryUpdated(address indexed newAddress);
    event DelegationRegistryUpdated(address indexed newAddress);
    event ProxyCreated(bytes32 id, address indexed newAddress);
    event FTokenImplUpdated(address indexed newAddress);
    event DebtTokenImplUpdated(address indexed newAddress);
    event NFTPriceOracleUpdated(address indexed newAddress);
    event LendingRateManagerUpdated(address indexed newAddress);
    event WETHUpdated(address indexed newAddress);
    event WETHGatewayUpdated(address indexed newAddress);

    function getMarketId() external view returns (string memory);

    function setMarketId(string calldata marketId) external;

    function getAddress(bytes32 id) external view returns (address);

    function setAddress(bytes32 id, address newAddress) external;

    function setAddressAsProxy(
        bytes32 id,
        address impl
    ) external;

    function getExecutionDelegate() external view returns (address);

    function setExecutionDelegate(address executionDelegate) external;

    function getExecutionManager() external view returns (address);

    function setExecutionManager(address executionManager) external;

    function getLending() external view returns (address);

    function setLending(address lending) external;

    function getPromissoryNote() external view returns (address);

    function setPromissoryNote(address promissoryNote) external;

    function getPromissoryNoteBundle() external view returns (address);

    function setPromissoryNoteBundle(address promissoryNote) external;

    function getObligationReceipt() external view returns (address);

    function setObligationReceipt(address obligationReceipt) external;

    function getObligationReceiptBundle() external view returns (address);

    function setObligationReceiptBundle(address obligationReceipt) external;

    function getLendingPool() external view returns (address);

    function setLendingPool(address pool) external;

    function getConfigurator() external view returns (address);

    function setConfigurator(address configurator) external;

    function setConfiguratorImpl(address configurator) external;

    function getCollateralManager() external view returns (address);

    function setCollateralManager(address collateralManager) external;

    function getPeerAdmin() external view returns (address);

    function setPeerAdmin(address admin) external;

    function getPoolAdmin() external view returns (address);

    function setPoolAdmin(address admin) external;

    function getEmergencyAdmin() external view returns (address);

    function setEmergencyAdmin(address admin) external;

    function getNFTPriceOracle() external view returns (address);

    function setNFTPriceOracle(address nftPriceOracle) external;

    function getLendingRateManager() external view returns (address);

    function setLendingRateManager(address lendingRateManager) external;

    function getPriceConsumerV3() external view returns (address);

    function setPriceConsumerV3(address priceConsumerV3) external;

    function getFluidToken() external view returns (address);

    function setFluidToken(address fluidToken) external;

    function getPoolIncentivesController() external view returns (address);

    function setPoolIncentivesController(address controller) external;

    function getPeerIncentivesController() external view returns (address);

    function setPeerIncentivesController(address controller) external;

    function getReferralManager() external view returns (address);

    function setReferralManager(address referralManager) external;

    function getTreasury() external view returns (address);

    function setTreasury(address treasury) external;

    function getDelegationRegistry() external view returns (address);

    function setDelegationRegistry(address delegationRegistry) external;

    function getFTokenImpl() external view returns (address);

    function setFTokenImpl(address fTokenImpl) external;

    function getDebtTokenImpl() external view returns (address);

    function setDebtTokenImpl(address debtTokenImpl) external;

    function getWETH() external view returns (address);

    function setWETH(address weth) external;

    function getWETHGateway() external view returns (address);

    function setWETHGateway(address weth) external;
}
```

{% endtab %}

{% tab title="IPoolIncentivesController.sol" %}

```solidity
// SPDX-License-Identifier: AGPL-3.0
pragma solidity 0.8.16;
pragma abicoder v2;

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

interface IPoolIncentivesController {
    event RewardsAccrued(address indexed _user, uint256 _amount);

    event RewardsClaimed(address indexed _user, uint256 _amount);

    /**
     * @dev Configure assets for a certain rewards emission
     * @param _assets The assets to incentivize
     * @param _emissionsPerSecond The emission for each asset
     */
    function configureAssets(
        IScaledBalanceToken[] calldata _assets,
        uint256[] calldata _emissionsPerSecond
    ) external;

    /**
     * @dev Called by the corresponding asset on any update that affects the rewards distribution
     * @param _user The address of the user
     * @param _totalSupply The total supply of the asset in the lending pool
     * @param _userBalance The balance of the user of the asset in the lending pool
     **/
    function handleAction(
        address _user,
        uint256 _totalSupply,
        uint256 _userBalance
    ) external;

    /**
     * @dev Returns the total of rewards of an user, already accrued + not yet accrued
     * @param _assets The assets to incentivize
     * @param _user The address of the user
     * @return The rewards
     **/
    function getRewardsBalance(
        IScaledBalanceToken[] calldata _assets,
        address _user
    ) external view returns (uint256);

    /**
     * @dev Claims reward for an user, on all the assets of the lending pool, accumulating the pending rewards
     * @param _assets The assets to incentivize
     * @param _amount Amount of rewards to claim
     * @return Rewards claimed
     **/
    function claimRewards(
        IScaledBalanceToken[] calldata _assets,
        uint256 _amount
    ) external returns (uint256);

    /**
     * @dev returns the unclaimed rewards of the user
     * @param _user the address of the user
     * @return the unclaimed user rewards
     */
    function getUserUnclaimedRewards(address _user)
        external
        view
        returns (uint256);
}
```

{% endtab %}

{% tab title="IScaledBalanceToken.sol" %}

```solidity
// SPDX-License-Identifier: AGPL-3.0
pragma solidity 0.8.16;

interface IScaledBalanceToken {
  /**
   * @dev Returns the scaled balance of the user. The scaled balance is the sum of all the
   * updated stored balance divided by the reserve's liquidity index at the moment of the update
   * @param user The user whose balance is calculated
   * @return The scaled balance of the user
   **/
  function scaledBalanceOf(address user) external view returns (uint256);

  /**
   * @dev Returns the scaled balance of the user and the scaled total supply.
   * @param user The address of the user
   * @return The scaled balance of the user
   * @return The scaled balance and the scaled total supply
   **/
  function getScaledUserBalanceAndSupply(address user) external view returns (uint256, uint256);

  /**
   * @dev Returns the scaled total supply of the variable debt token. Represents sum(debt/index)
   * @return The scaled total supply
   **/
  function scaledTotalSupply() external view returns (uint256);
}
```

{% endtab %}
{% endtabs %}