Controllers

/**
 * @title IRateComputer
 * @notice An interface that defines a contract that computes rates.
 */
interface IRateComputer {
    /// @notice Computes the rate for a token.
    /// @param token The address of the token to compute the rate for.
    /// @return rate The rate for the token.
    function computeRate(address token) external view returns (uint64);
}

library RateLibrary {
    struct Rate {
        uint64 target;
        uint64 current;
        uint32 timestamp;
    }
}
 
/**
 * @title IHistoricalRates
 * @notice An interface that defines a contract that stores historical rates.
 */
interface IHistoricalRates {
    /// @notice Gets an rate for a token at a specific index.
    /// @param token The address of the token to get the rates for.
    /// @param index The index of the rate to get, where index 0 contains the latest rate, and the last
    ///   index contains the oldest rate (uses reverse chronological ordering).
    /// @return rate The rate for the token at the specified index.
    function getRateAt(address token, uint256 index) external view returns (RateLibrary.Rate memory);
 
    /// @notice Gets the latest rates for a token.
    /// @param token The address of the token to get the rates for.
    /// @param amount The number of rates to get.
    /// @return rates The latest rates for the token, in reverse chronological order, from newest to oldest.
    function getRates(address token, uint256 amount) external view returns (RateLibrary.Rate[] memory);
 
    /// @notice Gets the latest rates for a token.
    /// @param token The address of the token to get the rates for.
    /// @param amount The number of rates to get.
    /// @param offset The index of the first rate to get (default: 0).
    /// @param increment The increment between rates to get (default: 1).
    /// @return rates The latest rates for the token, in reverse chronological order, from newest to oldest.
    function getRates(
        address token,
        uint256 amount,
        uint256 offset,
        uint256 increment
    ) external view returns (RateLibrary.Rate[] memory);
 
    /// @notice Gets the number of rates for a token.
    /// @param token The address of the token to get the number of rates for.
    /// @return count The number of rates for the token.
    function getRatesCount(address token) external view returns (uint256);
 
    /// @notice Gets the capacity of rates for a token.
    /// @param token The address of the token to get the capacity of rates for.
    /// @return capacity The capacity of rates for the token.
    function getRatesCapacity(address token) external view returns (uint256);
 
    /// @notice Sets the capacity of rates for a token.
    /// @param token The address of the token to set the capacity of rates for.
    /// @param amount The new capacity of rates for the token.
    function setRatesCapacity(address token, uint256 amount) external;
}

/// @title IUpdateByToken
/// @notice An interface that defines a contract that is updateable as per the input data.
abstract contract IUpdateable {
/// @notice Performs an update as per the input data.
/// @param data Any data needed for the update.
/// @return b True if anything was updated; false otherwise.
function update(bytes memory data) public virtual returns (bool b);
 
    /// @notice Checks if an update needs to be performed.
    /// @param data Any data relating to the update.
    /// @return b True if an update needs to be performed; false otherwise.
    function needsUpdate(bytes memory data) public view virtual returns (bool b);
 
    /// @notice Check if an update can be performed by the caller (if needed).
    /// @dev Tries to determine if the caller can call update with a valid observation being stored.
    /// @dev This is not meant to be called by state-modifying functions.
    /// @param data Any data relating to the update.
    /// @return b True if an update can be performed by the caller; false otherwise.
    function canUpdate(bytes memory data) public view virtual returns (bool b);
 
    /// @notice Gets the timestamp of the last update.
    /// @param data Any data relating to the update.
    /// @return A unix timestamp.
    function lastUpdateTime(bytes memory data) public view virtual returns (uint256);
 
    /// @notice Gets the amount of time (in seconds) since the last update.
    /// @param data Any data relating to the update.
    /// @return Time in seconds.
    function timeSinceLastUpdate(bytes memory data) public view virtual returns (uint256);
 
}
 

/**
 * @title IPeriodic
 * @notice An interface that defines a contract containing a period.
 * @dev This typically refers to an update period.
 */
interface IPeriodic {
    /// @notice Gets the period, in seconds.
    /// @return periodSeconds The period, in seconds.
    function period() external view returns (uint256 periodSeconds);
 
    // @notice Gets the number of observations made every period.
    // @return granularity The number of observations made every period.
    function granularity() external view returns (uint256 granularity);
}

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);
}