/**
 * File helper functions for Telegram Bot API
 * @module helpers/file-helpers
 */
import type { TelegramBotClient } from '../client/TelegramBotClient.js';
import type { HttpRequestOptions } from '../types/http-client.types.js';
/**
 * Get Telegram file download URL
 * Retrieves file_path from Telegram API and constructs download URL
 *
 * @param fileId - Telegram file_id
 * @param client - TelegramBotClient instance
 * @param routeId - Route ID for multi-token setup (optional)
 * @returns Download URL for the file
 *
 * @throws {Error} If file_path is not available in response
 *
 * @example
 * ```typescript
 * const url = await getFileUrl(fileId, bot);
 * console.log('Download from:', url);
 * // "https://api.telegram.org/file/bot<token>/photos/file_123.jpg"
 * ```
 */
export declare function getFileUrl(fileId: string, client: TelegramBotClient, routeId?: string): Promise<string>;
/**
 * Download Telegram file as Buffer
 * Combines getFile API call with file download using HTTP client
 *
 * @param fileId - Telegram file_id
 * @param client - TelegramBotClient instance
 * @param routeId - Route ID for multi-token setup (optional)
 * @param options - Download options (timeout, retries)
 * @returns File content as Buffer
 *
 * @example
 * ```typescript
 * // With default settings
 * const buffer = await getTelegramFileBuffer(fileId, bot);
 * await fs.writeFile('photo.jpg', buffer);
 *
 * // With custom timeout for large files
 * const buffer = await getTelegramFileBuffer(fileId, bot, undefined, {
 *   timeout: 120000,  // 2 minutes
 *   retries: 5
 * });
 * ```
 */
export declare function getTelegramFileBuffer(fileId: string, client: TelegramBotClient, routeId?: string, options?: HttpRequestOptions): Promise<Buffer>;
/**
 * Download Telegram file as ReadableStream
 * Useful for large files or streaming to destination
 *
 * @param fileId - Telegram file_id
 * @param client - TelegramBotClient instance
 * @param routeId - Route ID for multi-token setup (optional)
 * @param options - Download options (only timeout is used for streams)
 * @returns File content as ReadableStream
 *
 * @example
 * ```typescript
 * import { pipeline } from 'stream/promises';
 * import { Readable } from 'stream';
 *
 * const stream = await getTelegramFileStream(fileId, bot);
 * await pipeline(
 *   Readable.fromWeb(stream),
 *   fs.createWriteStream('video.mp4')
 * );
 * ```
 */
export declare function getTelegramFileStream(fileId: string, client: TelegramBotClient, routeId?: string, options?: HttpRequestOptions): Promise<ReadableStream>;
/**
 * Download file from any URL as Buffer
 * Not Telegram-specific, uses HTTP client for retry/timeout logic
 *
 * @param url - File URL to download
 * @param client - TelegramBotClient instance (for HTTP client access)
 * @param options - Download options (timeout, retries)
 * @returns File content as Buffer
 *
 * @example
 * ```typescript
 * // Download external file
 * const buffer = await downloadFileBuffer(
 *   'https://example.com/report.pdf',
 *   bot,
 *   { timeout: 60000, retries: 3 }
 * );
 * ```
 */
export declare function downloadFileBuffer(url: string, client: TelegramBotClient, options?: HttpRequestOptions): Promise<Buffer>;
/**
 * Download file from any URL as ReadableStream
 * Not Telegram-specific
 *
 * @param url - File URL to download
 * @param client - TelegramBotClient instance
 * @param options - Download options (only timeout)
 * @returns File content as ReadableStream
 *
 * @example
 * ```typescript
 * import { pipeline } from 'stream/promises';
 * import { Readable } from 'stream';
 *
 * const stream = await downloadFileStream(url, bot);
 * await pipeline(
 *   Readable.fromWeb(stream),
 *   fs.createWriteStream('file.pdf')
 * );
 * ```
 */
export declare function downloadFileStream(url: string, client: TelegramBotClient, options?: HttpRequestOptions): Promise<ReadableStream>;
/** @deprecated Use getTelegramFileBuffer instead */
export declare const getFileBuffer: typeof getTelegramFileBuffer;
/** @deprecated Use getTelegramFileStream instead */
export declare const getFileStream: typeof getTelegramFileStream;