import { VideoQuality } from './types';
export declare class SimpleLRUCache<V> {
    private max;
    private ttlMs;
    private map;
    constructor(max: number, ttlMs: number);
    get(key: string): V | undefined;
    set(key: string, value: V): void;
    clear(): void;
}
export declare class ConcurrencyLimiter {
    private max;
    private running;
    private queue;
    constructor(max: number);
    acquire(): Promise<void>;
    release(): void;
}
export declare function formatDuration(seconds: number): string;
export declare function formatPublishTime(ms: number): string;
export declare function pickBestQuality(videoBackup: any[]): VideoQuality[];
export declare function getNestedValue(obj: any, path: string): any;
export declare function getFirst(obj: any, paths: string[], fallback?: any): any;
export declare function safeJsonParse(data: any): any;
export declare function normalizeUrl(url: any): string;
export declare function parseCount(val: any): number;
export declare const delay: (ms: number) => Promise<unknown>;
export declare function getErrorMessage(error: unknown): string;
export declare function parseFieldMapping(mappingStr: string): Record<string, string> | undefined;