import { TranscriptConfig, TranscriptSegment, TranscriptResult, CaptionTrackInfo } from './types';
/**
 * Fetches YouTube video transcripts and caption metadata using the Innertube API.
 *
 * Can be used as an instance (with shared config) or via static/convenience methods.
 *
 * @example
 * ```typescript
 * // Instance usage with shared config
 * const yt = new YoutubeTranscript({ lang: 'en' });
 * const transcript = await yt.fetchTranscript('dQw4w9WgXcQ');
 * const languages = await yt.listLanguages('dQw4w9WgXcQ');
 *
 * // Static method
 * const transcript = await YoutubeTranscript.fetchTranscript('dQw4w9WgXcQ', { lang: 'en' });
 *
 * // Opt-in to video details
 * const { videoDetails, segments } = await YoutubeTranscript.fetchTranscript('dQw4w9WgXcQ', {
 *   videoDetails: true,
 * });
 *
 * // Convenience export
 * const transcript = await fetchTranscript('dQw4w9WgXcQ');
 * const languages = await listLanguages('dQw4w9WgXcQ');
 * ```
 */
export declare class YoutubeTranscript {
    private config?;
    constructor(config?: TranscriptConfig | undefined);
    /**
     * Fetch caption tracks and the player response from the Innertube player API.
     * Shared logic used by both fetchTranscript and listLanguages.
     */
    private _fetchCaptionTracks;
    /**
     * Extract VideoDetails from the Innertube player response.
     */
    private _extractVideoDetails;
    /**
     * Fetch the transcript for a YouTube video.
     *
     * When `videoDetails` is set to `true` in the config, returns a {@link TranscriptResult}
     * containing both video metadata and transcript segments. Otherwise returns an array of
     * {@link TranscriptSegment} objects.
     *
     * **Note:** The instance method returns a union type because `videoDetails` is set at
     * construction time. For automatic type narrowing, use the static method or the
     * `fetchTranscript` convenience export instead.
     *
     * @param videoId - A YouTube video ID (11 characters) or full YouTube URL.
     * @returns An array of transcript segments, or a TranscriptResult if `videoDetails` is enabled.
     * @throws {@link YoutubeTranscriptInvalidVideoIdError} if the video ID/URL is invalid.
     * @throws {@link YoutubeTranscriptVideoUnavailableError} if the video is unavailable.
     * @throws {@link YoutubeTranscriptDisabledError} if transcripts are disabled.
     * @throws {@link YoutubeTranscriptNotAvailableError} if no transcript is available.
     * @throws {@link YoutubeTranscriptNotAvailableLanguageError} if the requested language is unavailable.
     * @throws {@link YoutubeTranscriptTooManyRequestError} if rate-limited by YouTube.
     */
    fetchTranscript(videoId: string): Promise<TranscriptSegment[] | TranscriptResult>;
    /**
     * List available caption languages for a YouTube video.
     *
     * Queries the Innertube player API to discover what caption tracks exist,
     * without downloading any transcript data.
     *
     * @param videoId - A YouTube video ID (11 characters) or full YouTube URL.
     * @returns An array of available caption track info objects.
     * @throws {@link YoutubeTranscriptInvalidVideoIdError} if the video ID/URL is invalid.
     * @throws {@link YoutubeTranscriptVideoUnavailableError} if the video is unavailable.
     * @throws {@link YoutubeTranscriptDisabledError} if transcripts are disabled.
     * @throws {@link YoutubeTranscriptNotAvailableError} if no captions are available.
     * @throws {@link YoutubeTranscriptTooManyRequestError} if rate-limited by YouTube.
     *
     * @example
     * ```typescript
     * const yt = new YoutubeTranscript();
     * const languages = await yt.listLanguages('dQw4w9WgXcQ');
     * // [
     * //   { languageCode: 'en', languageName: 'English', isAutoGenerated: false },
     * //   { languageCode: 'es', languageName: 'Spanish (auto-generated)', isAutoGenerated: true },
     * // ]
     * ```
     */
    listLanguages(videoId: string): Promise<CaptionTrackInfo[]>;
    /**
     * Static convenience method to fetch a transcript without creating an instance.
     *
     * @param videoId - A YouTube video ID (11 characters) or full YouTube URL.
     * @param config - Optional configuration options.
     * @returns An array of transcript segments, or a {@link TranscriptResult} when `videoDetails: true`.
     */
    static fetchTranscript(videoId: string): Promise<TranscriptSegment[]>;
    static fetchTranscript(videoId: string, config: TranscriptConfig & {
        videoDetails: true;
    }): Promise<TranscriptResult>;
    static fetchTranscript(videoId: string, config: TranscriptConfig): Promise<TranscriptSegment[]>;
    /**
     * Static convenience method to list available caption languages without creating an instance.
     *
     * @param videoId - A YouTube video ID (11 characters) or full YouTube URL.
     * @param config - Optional configuration options.
     * @returns An array of available caption track info objects.
     */
    static listLanguages(videoId: string, config?: TranscriptConfig): Promise<CaptionTrackInfo[]>;
}
export type { CacheStrategy, CaptionTrackInfo, Thumbnail, TranscriptConfig, TranscriptResponse, TranscriptResult, TranscriptSegment, VideoDetails, FetchParams, } from './types';
export { InMemoryCache, FsCache } from './cache';
export { toSRT, toVTT, toPlainText } from './formatters';
export * from './errors';
/**
 * Convenience function to fetch a YouTube video transcript.
 *
 * @param videoId - A YouTube video ID (11 characters) or full YouTube URL.
 * @param config - Optional configuration options.
 * @returns An array of transcript segments, or a {@link TranscriptResult} when `videoDetails: true`.
 *
 * @example
 * ```typescript
 * import { fetchTranscript } from 'youtube-transcript-plus';
 *
 * // Returns TranscriptSegment[]
 * const transcript = await fetchTranscript('dQw4w9WgXcQ');
 *
 * // Returns TranscriptResult with video details
 * const { videoDetails, segments } = await fetchTranscript('dQw4w9WgXcQ', {
 *   videoDetails: true,
 * });
 * ```
 */
export declare function fetchTranscript(videoId: string): Promise<TranscriptSegment[]>;
export declare function fetchTranscript(videoId: string, config: TranscriptConfig & {
    videoDetails: true;
}): Promise<TranscriptResult>;
export declare function fetchTranscript(videoId: string, config: TranscriptConfig): Promise<TranscriptSegment[]>;
/**
 * Convenience function to list available caption languages for a YouTube video.
 *
 * @param videoId - A YouTube video ID (11 characters) or full YouTube URL.
 * @param config - Optional configuration options.
 * @returns An array of available caption track info objects.
 *
 * @example
 * ```typescript
 * import { listLanguages } from 'youtube-transcript-plus';
 * const languages = await listLanguages('dQw4w9WgXcQ');
 * ```
 */
export declare const listLanguages: typeof YoutubeTranscript.listLanguages;