/**
 * Ensure that a directory exists, create it recursively if it doesn't.
 *
 * @param dirPath - Absolute or relative path to the directory.
 */
export declare function ensureDirectoryExists(dirPath: string): Promise<void>;
/**
 * Append a log message to a file.
 * - Automatically trims old log files if total log size exceeds threshold.
 *
 * @param dir - Directory path to save logs.
 * @param filename - File name (e.g., 2025-04-05.log).
 * @param content - Log message to write.
 */
export declare function appendToFile(dir: string, filename: string, content: string): Promise<void>;
/**
 * Check total directory size and delete oldest files if limit exceeded.
 *
 * @param dir - Log directory.
 * @param maxSizeBytes - Size threshold in bytes.
 */
export declare function trimLogsIfTooLarge(dir: string, maxSizeBytes: number): Promise<void>;
/**
 * Reads a file as UTF-8 encoded text.
 *
 * @param filePath - The absolute or relative path to the file.
 * @returns A promise that resolves to the file contents as a string.
 */
export declare function readFile(filePath: string): Promise<string>;
/**
 * Checks whether a file exists at the given path.
 *
 * @param filePath - The path to the file to check.
 * @returns A promise that resolves to true if the file exists, false otherwise.
 */
export declare function exists(filePath: string): Promise<boolean>;
/**
 * Remove directory from directory path
 *
 * @param dirPath  - The path to remove target of diretory path
 */
export declare function removeDirectory(dirPath: string): Promise<void>;