import type { MultiCacheInstances } from '../types/index.js';
import type { CacheTagRegistry } from '../types/CacheTagRegistry.js';
/**
 * A helper class to debounce cache tag invalidation.
 *
 * This prevents having too many invalidation requests coming in at once that
 * could lead to performance issues since tag invalidation can be very
 * inefficient.
 */
export declare class CacheTagInvalidator {
    /**
     * The caches.
     */
    private cache;
    /**
     * The cache tag registry.
     */
    private cacheTagRegistry;
    /**
     * Buffer of tags to invalidate in the next run.
     */
    private tags;
    /**
     * The current timeout ID for the next run. Reset after each run.
     */
    private timeout;
    constructor(
    /**
     * The caches.
     */
    cache: MultiCacheInstances, 
    /**
     * The cache tag registry.
     */
    cacheTagRegistry: CacheTagRegistry | null);
    /**
     * Add tags to be purged.
     */
    add(tags?: string[]): void;
    getCacheTags(cacheName: keyof MultiCacheInstances, key: string): Promise<string[] | undefined>;
    /**
     * Invalidate the tags in the buffer.
     */
    invalidate(): Promise<boolean>;
}