/**
 * Memory Storage Adapter
 *
 * In-memory storage implementation for development and testing.
 * Supports TTL, pattern matching, pub/sub via EventEmitter.
 */
import { BaseStorageAdapter } from './base';
import type { MemoryAdapterOptions, SetOptions, MessageHandler, Unsubscribe } from '../types';
/**
 * In-memory storage adapter.
 *
 * Features:
 * - TTL support with lazy expiration + optional background sweeper
 * - Pattern matching for keys() with ReDoS protection
 * - Pub/sub via EventEmitter
 * - Optional LRU eviction
 *
 * @example
 * ```typescript
 * const adapter = new MemoryStorageAdapter({
 *   enableSweeper: true,
 *   sweepIntervalSeconds: 60,
 * });
 *
 * await adapter.connect();
 * await adapter.set('key', 'value', { ttlSeconds: 300 });
 * const value = await adapter.get('key');
 * await adapter.disconnect();
 * ```
 */
export declare class MemoryStorageAdapter extends BaseStorageAdapter {
    protected readonly backendName = "memory";
    private readonly store;
    private readonly emitter;
    private sweepInterval?;
    private readonly options;
    private accessOrder;
    constructor(options?: MemoryAdapterOptions);
    connect(): Promise<void>;
    disconnect(): Promise<void>;
    ping(): Promise<boolean>;
    get(key: string): Promise<string | null>;
    protected doSet(key: string, value: string, options?: SetOptions): Promise<void>;
    delete(key: string): Promise<boolean>;
    exists(key: string): Promise<boolean>;
    expire(key: string, ttlSeconds: number): Promise<boolean>;
    ttl(key: string): Promise<number | null>;
    keys(pattern?: string): Promise<string[]>;
    incr(key: string): Promise<number>;
    decr(key: string): Promise<number>;
    incrBy(key: string, amount: number): Promise<number>;
    supportsPubSub(): boolean;
    publish(channel: string, message: string): Promise<number>;
    subscribe(channel: string, handler: MessageHandler): Promise<Unsubscribe>;
    /**
     * Delete an entry and clear its timeout.
     */
    private deleteEntry;
    /**
     * Clear timeout for an entry.
     */
    private clearEntryTimeout;
    /**
     * Clear all timeouts.
     */
    private clearAllTimeouts;
    /**
     * Update LRU access order.
     */
    private touchLRU;
    /**
     * Remove key from LRU tracking.
     */
    private removeLRU;
    /**
     * Evict oldest entry (LRU).
     */
    private evictOldest;
    /**
     * Start background sweeper.
     */
    private startSweeper;
    /**
     * Stop background sweeper.
     */
    private stopSweeper;
    /**
     * Sweep expired entries.
     */
    private sweep;
    /**
     * Get storage statistics.
     */
    getStats(): {
        size: number;
        maxEntries: number;
        sweeperActive: boolean;
    };
}