/**
 * Formats a byte value into a human-readable string with units.
 *
 * @param receivedBytes - The number of bytes to format (as number or string)
 * @param decimals - The number of decimal places to display (default: 0)
 * @returns A formatted string with value and unit (e.g., "1.5MB")
 *
 * @example
 * ```ts
 * formatBytes(1024) // '1KB'
 * formatBytes(1536, 1) // '1.5KB'
 * ```
 */
export declare function formatBytes(receivedBytes: number | string, decimals?: number): string;
/**
 * Extracts the file extension from a string, removing the leading dot if present.
 *
 * @param ext - The file extension string (may include leading dot)
 * @returns The extension without leading dot, or the original value if no dot
 *
 * @example
 * ```ts
 * getFileExtension('.jpg') // 'jpg'
 * getFileExtension('png') // 'png'
 * ```
 */
export declare const getFileExtension: (ext?: string | null) => string | null | undefined;
/**
 * Prefixes a relative file URL with the backend URL if needed.
 *
 * @param fileURL - The file URL to potentially prefix
 * @returns The full URL with backend prefix if it was relative, otherwise unchanged
 *
 * @example
 * ```ts
 * prefixFileUrlWithBackendUrl('/uploads/image.jpg') // 'http://localhost:1337/uploads/image.jpg'
 * prefixFileUrlWithBackendUrl('https://cdn.example.com/image.jpg') // 'https://cdn.example.com/image.jpg'
 * ```
 */
export declare const prefixFileUrlWithBackendUrl: (fileURL?: string) => string | undefined;
/**
 * Extracts a filename from a URL's pathname.
 *
 * @param url - The URL to extract the filename from
 * @returns The filename extracted from the URL path, or 'file' if none found
 *
 * @example
 * ```ts
 * getFilenameFromUrl('https://example.com/images/photo.jpg') // 'photo.jpg'
 * getFilenameFromUrl('https://example.com/') // 'file'
 * ```
 */
export declare function getFilenameFromUrl(url: string): string;
/**
 * Validates a newline-separated string of URLs.
 *
 * @param urlsString - A string containing URLs separated by newlines
 * @returns An object with validated URLs array and optional error message
 *
 * @example
 * ```ts
 * const { urls, error } = validateUrls('https://example.com/a.jpg\nhttps://example.com/b.jpg');
 * if (error) {
 *   console.error(error);
 * } else {
 *   console.log(urls); // ['https://example.com/a.jpg', 'https://example.com/b.jpg']
 * }
 * ```
 */
export declare function validateUrls(urlsString: string): {
    urls: string[];
    error: string | null;
};