/**
 * Message Acknowledgments
 *
 * Delivery confirmation for critical messages
 */
export declare interface AckConfig {
  enabled?: boolean
  timeout?: number
  retryAttempts?: number
}
export declare interface PendingAck {
  messageId: string
  channel: string
  event: string
  data: unknown
  socketId: string
  timestamp: number
  attempts: number
  resolve: (value: boolean) => void
  reject: (reason: Error) => void
}
export declare class AcknowledgmentManager {
  constructor(config?: AckConfig);
  isEnabled(): boolean;
  register(messageId: string, channel: string, event: string, data: unknown, socketId: string): Promise<boolean>;
  acknowledge(messageId: string): boolean;
  getPending(): PendingAck[];
  getPendingById(messageId: string): PendingAck | undefined;
  clear(): void;
  getStats(): { pending: number, oldest?: number };
}