import type { LogLevel } from '../core/types';
/**
 * Log message formatter function signature.
 */
export type LogFormatter = (level: LogLevel, message: string, args: unknown[], appName?: string) => string;
/**
 * Format additional arguments for logging in a structured way.
 *
 * @param args - Array of arguments to format
 * @returns Formatted string representation of arguments
 */
export declare const formatArgs: (args: unknown[]) => string;
/**
 * Next.js specific formatter with time-only timestamps and cleaner format
 */
export declare const nextjsFormatter: LogFormatter;
/**
 * Register a custom formatter for log messages.
 *
 * @param name - Name to identify the formatter
 * @param formatter - The formatter function
 */
export declare const registerFormatter: (name: string, formatter: LogFormatter) => void;
/**
 * Get a formatter by name, falling back to default if not found.
 *
 * @param name - The formatter name to retrieve
 * @returns The formatter function
 */
export declare const getFormatter: (name?: string) => LogFormatter;
/**
 * Format a log message using the specified formatter.
 *
 * @param level - Log level
 * @param message - Log message
 * @param args - Additional log arguments
 * @param formatterName - Name of formatter to use
 * @param appName - Optional application name
 * @returns Formatted log message
 */
export declare const formatMessage: (level: LogLevel, message: string, args?: unknown[], formatterName?: string, appName?: string) => string;