import { TranscriptConfig, TranscriptSegment } from './types.js';
/**
 * Service class for fetching YouTube video transcripts
 */
export declare class YoutubeTranscript {
    /**
     * Fetches the transcript for a YouTube video
     * @param videoId Video URL or ID
     * @param config Configuration options
     * @returns Array of transcript segments
     */
    static fetchTranscript(videoId: string, config?: TranscriptConfig): Promise<TranscriptSegment[]>;
    /**
     * Creates fetch options with proxy configuration if provided
     */
    private static getFetchOptions;
    /**
     * Fetches the video page content
     */
    private static fetchVideoPage;
    /**
     * Extracts and validates captions data from the video page
     */
    private static parseCaptionsData;
    /**
     * Extracts captions JSON data from the page content
     */
    private static extractCaptionsJson;
    /**
     * Handles various error cases from the video page
     */
    private static handlePageErrors;
    /**
     * Gets the URL for the transcript in the requested language
     */
    private static getTranscriptUrl;
    /**
     * Validates that the requested language is available
     */
    private static validateLanguageAvailability;
    /**
     * Fetches and parses the transcript XML
     */
    private static fetchAndParseTranscript;
    /**
     * Extracts the video ID from either a full URL or direct ID
     */
    private static retrieveVideoId;
}