import { MimeType } from '../types/course';

/**
 * Formats file size in bytes to a human-readable string
 */
export declare function formatFileSize(size: number): string;
/**
 * Returns icon information based on file type
 */
export declare function getFileTypeIcon(fileType: MimeType): {
    icon: string;
    color: string;
};
/**
 * Returns accepted file types based on upload type
 */
export declare function getAcceptedFileTypes(type: MimeType): string;
/**
 * Returns human-readable formats for each upload type
 */
export declare function getReadableFormats(type: MimeType): string;
/**
 * Extracts the first frame of a video file as a thumbnail image
 */
export declare const extractThumbnailFromVideo: (videoFile: File) => Promise<File | null>;
export declare const fetchThumbnailFile: (imageUrl: string) => Promise<{
    id: string;
    fileName: string;
    size: number;
    mimeType: MimeType;
    file: File;
} | null>;
/**
 * Gets the duration of a video file in seconds
 */
export declare const getVideoDuration: (videoFile: File) => Promise<number>;
/**
 * Formats a duration in seconds to a human-readable string.
 * - If seconds < 60: "SS seconds" (e.g., "32 seconds")
 * - If 60 <= seconds < 3600: "MM:SS min" (e.g., "01:30 min")
 * - If seconds >= 3600: "HH:MM hr" (e.g., "01:30 hr")
 */
export declare function formatDuration(totalSeconds: number): string;