/**
 * EphemeralStore - In-memory store for transient data like presence
 *
 * Data stored here is not persisted to database and expires after TTL.
 * Used for presence, awareness, and other real-time ephemeral data.
 */
export interface EphemeralEntry<T = any> {
    data: T;
    userId: string;
    clientId: string;
    channel: string;
    expiresAt: number;
    updatedAt: number;
}
export interface EphemeralStoreOptions {
    /** Time-to-live in milliseconds (default: 60000 = 60s) */
    ttl?: number;
    /** Cleanup interval in milliseconds (default: 30000 = 30s) */
    cleanupInterval?: number;
    /** Callback when an entry expires */
    onExpire?: (entry: EphemeralEntry) => void;
}
/**
 * Generic in-memory store for ephemeral data
 */
export declare class EphemeralStore<T = any> {
    private store;
    private ttl;
    private cleanupInterval;
    private onExpire?;
    constructor(options?: EphemeralStoreOptions);
    /**
     * Store or update an entry
     */
    set(key: string, entry: Omit<EphemeralEntry<T>, 'expiresAt' | 'updatedAt'>): void;
    /**
     * Get an entry by key
     * Returns null if not found or expired
     */
    get(key: string): T | null;
    /**
     * Get full entry with metadata
     */
    getEntry(key: string): EphemeralEntry<T> | null;
    /**
     * Delete an entry
     * Returns true if entry existed
     */
    delete(key: string): boolean;
    /**
     * Get all entries for a specific channel
     */
    getByChannel(channel: string): EphemeralEntry<T>[];
    /**
     * Get all entries for a specific user across all channels
     */
    getByUser(userId: string): EphemeralEntry<T>[];
    /**
     * Get all data values in a channel (without metadata)
     * Optionally exclude a specific client
     */
    getAllInChannel(channel: string, excludeClientId?: string): T[];
    /**
     * Get entry by channel and user
     */
    getByChannelAndUser(channel: string, userId: string): EphemeralEntry<T> | null;
    /**
     * Remove all entries for a specific client
     */
    removeByClient(clientId: string): number;
    /**
     * Remove all entries in a channel
     */
    removeByChannel(channel: string): number;
    /**
     * Clean up expired entries
     * Called automatically on interval
     */
    cleanup(): void;
    /**
     * Get the number of entries in the store
     */
    size(): number;
    /**
     * Clear all entries
     */
    clear(): void;
    /**
     * Stop cleanup interval and clear store
     */
    destroy(): void;
}