import type { SmartLinkResponse } from '@atlaskit/linking-types/smart-link';
type CacheEntry = {
    data: SmartLinkResponse;
    timestamp: number;
};
/**
 * Singleton cache client for smart link responses. Uses sessionStorage for per-tab isolation (no cross-tab conflicts).
 * If switching to localStorage for cross-tab sharing, add a 'storage' event listener in the constructor to sync
 * memoryCache when other tabs modify the cache, preventing race conditions from concurrent writes.
 */
export declare class SmartCardLocalCacheClient {
    private static instance;
    private readonly storageClient;
    private maxItems;
    private memoryCache;
    private pendingWrite;
    private constructor();
    /**
     * Gets the singleton instance of SmartCardLocalCacheClient.
     * This ensures all callers share the same in-memory cache and prevents
     * race conditions when multiple instances write to the same storage key.
     * @param maxItems Maximum number of items to store in the cache (only used on first instantiation)
     * @returns The singleton instance
     */
    static getInstance(maxItems?: number): SmartCardLocalCacheClient;
    /**
     * Resets the singleton instance. Only intended for testing purposes.
     * @internal
     */
    static resetInstance(): void;
    /**
     * Retrieves the entire cache object from memory
     * @returns The entire cache object
     */
    getCache: () => Record<string, CacheEntry>;
    /**
     * Caches the SmartLinkResponse against the provided url in storage
     * @param url The url (key) to store the response against
     * @param response The SmartLinkResponse to be cached in storage
     */
    setItem: (url: string, response: SmartLinkResponse) => void;
    /**
     * Retrieves the cached SmartLinkResponse for the provided url from storage (if it exists)
     * @param url The url (key) to retrieve the cached response for
     * @returns The cached SmartLinkResponse if it exists, else undefined
     */
    getItem: (url: string | undefined) => SmartLinkResponse | undefined;
    /**
     * Checks if a cached entry exists for the provided url in storage
     * @param url The url (key) to check for existence in the cache
     * @returns True if a cached entry exists, else false
     */
    isUrlInCache: (url: string) => boolean;
}
export {};