import { CLSGuardConfig, CLSGuardInterface, CLSMeasurement, Dimensions, LayoutReservation, ReservationStrategy } from './types';
/**
 * CLS Guard implementation that prevents layout shifts through
 * reservations and monitors actual CLS scores.
 *
 * @example
 * ```typescript
 * const guard = createCLSGuard({ maxCLS: 0.05 });
 *
 * // Reserve space for an image
 * const reservation = guard.createReservation('hero-image', {
 *   width: 1200,
 *   height: 600
 * }, 'skeleton');
 *
 * // Monitor CLS
 * const unsubscribe = guard.observeCLS((measurement) => {
 *   if (measurement.thresholdExceeded) {
 *     console.warn('CLS threshold exceeded:', measurement.score);
 *   }
 * });
 * ```
 */
export declare class CLSGuard implements CLSGuardInterface {
    private readonly _reservations;
    private readonly _reservationElements;
    private readonly _measurements;
    private readonly _callbacks;
    private _observer;
    private _sessionEntries;
    private _sessionStart;
    private _destroyed;
    constructor(config?: Partial<CLSGuardConfig>);
    private _config;
    /**
     * Current configuration.
     */
    get config(): CLSGuardConfig;
    private _currentScore;
    /**
     * Current CLS score.
     */
    get currentScore(): number;
    /**
     * Updates the guard configuration.
     */
    configure(config: Partial<CLSGuardConfig>): void;
    /**
     * Creates a layout reservation to prevent CLS.
     *
     * @param id - Unique identifier for the reservation
     * @param dimensions - Dimensions to reserve
     * @param strategy - Reservation strategy (defaults to config)
     * @returns The created reservation
     */
    createReservation(id: string, dimensions: Dimensions, strategy?: ReservationStrategy): LayoutReservation;
    /**
     * Releases a layout reservation.
     *
     * @param id - The reservation ID to release
     */
    releaseReservation(id: string): void;
    /**
     * Measures the current CLS score.
     *
     * @returns CLS measurement result
     */
    measureCLS(): CLSMeasurement;
    /**
     * Subscribes to CLS updates.
     *
     * @param callback - Callback for CLS measurements
     * @returns Unsubscribe function
     */
    observeCLS(callback: (measurement: CLSMeasurement) => void): () => void;
    /**
     * Cleans up all resources.
     */
    destroy(): void;
    /**
     * Gets the reservation element for a given ID.
     *
     * @param id - Reservation ID
     * @returns The reservation element or undefined
     */
    getReservationElement(id: string): HTMLElement | undefined;
    /**
     * Inserts a reservation element at a specific location.
     *
     * @param id - Reservation ID
     * @param container - Container element to insert into
     * @param position - Insert position
     */
    insertReservationElement(id: string, container: HTMLElement, position?: 'prepend' | 'append' | 'before' | 'after'): void;
    /**
     * Initializes the Performance Observer for CLS tracking.
     */
    private _initializeObserver;
    /**
     * Processes a layout shift entry.
     */
    private _processLayoutShift;
    /**
     * Extracts element ID from layout shift sources.
     */
    private _extractElementId;
    /**
     * Creates a reservation element in the DOM.
     */
    private _createReservationElement;
    /**
     * Asserts that the guard has not been destroyed.
     */
    private _assertNotDestroyed;
}
/**
 * Creates a new CLSGuard instance.
 *
 * @param config - Optional configuration overrides
 * @returns A new CLSGuard instance
 */
export declare function createCLSGuard(config?: Partial<CLSGuardConfig>): CLSGuardInterface;
/**
 * Calculates the predicted CLS impact of a layout change.
 *
 * @param beforeRects - Element positions before change
 * @param afterRects - Element positions after change
 * @param viewportDimensions - Viewport dimensions
 * @returns Predicted CLS score
 */
export declare function predictCLSImpact(beforeRects: ReadonlyMap<string, DOMRect>, afterRects: ReadonlyMap<string, DOMRect>, viewportDimensions: Dimensions): number;
/**
 * Creates optimized dimension reservations based on content hints.
 *
 * @param contentHints - Array of content hints with expected dimensions
 * @returns Array of optimized reservations
 */
export declare function createOptimizedReservations(contentHints: Array<{
    id: string;
    type: 'image' | 'video' | 'text' | 'custom';
    expectedDimensions?: Dimensions;
    aspectRatio?: number;
}>): Array<{
    id: string;
    dimensions: Dimensions;
    strategy: ReservationStrategy;
}>;