/**
 * Comprehensive logging system for the General Translation library.
 * Provides structured logging with multiple levels and configurable output.
 */
export type LogLevel = 'debug' | 'info' | 'warn' | 'error' | 'off';
export type LogMetadataValue = string | number | boolean | null | undefined | Date | Error | LogMetadataValue[] | {
    [key: string]: LogMetadataValue;
};
export type LogMetadata = Record<string, LogMetadataValue>;
export interface LogEntry {
    level: LogLevel;
    message: string;
    timestamp: Date;
    context?: string;
    metadata?: LogMetadata;
}
export interface LoggerConfig {
    /** Minimum log level to output. */
    level: LogLevel;
    /** Whether to include timestamps in log output. */
    includeTimestamp: boolean;
    /** Whether to include context information. */
    includeContext: boolean;
    /** Custom prefix for all log messages. */
    prefix?: string;
    /** Whether to output to console (default: true) */
    enableConsole: boolean;
    /** Custom log handlers. */
    handlers?: LogHandler[];
}
export interface LogHandler {
    handle(entry: LogEntry): void;
}
/**
 * Console log handler that outputs formatted messages to console
 */
export declare class ConsoleLogHandler implements LogHandler {
    private config;
    constructor(config: LoggerConfig);
    handle(entry: LogEntry): void;
}
/**
 * Main Logger class providing structured logging capabilities.
 */
export declare class Logger {
    private config;
    private handlers;
    constructor(config?: Partial<LoggerConfig>);
    /**
     * Add a custom log handler
     */
    addHandler(handler: LogHandler): void;
    /**
     * Remove a log handler
     */
    removeHandler(handler: LogHandler): void;
    /**
     * Update logger configuration
     */
    configure(config: Partial<LoggerConfig>): void;
    /**
     * Check if a log level should be output based on current configuration
     */
    private shouldLog;
    /**
     * Internal logging method that creates log entries and passes them to handlers
     */
    private log;
    /**
     * Log a debug message
     * Used for detailed diagnostic information, typically of interest only when diagnosing problems
     */
    debug(message: string, context?: string, metadata?: LogMetadata): void;
    /**
     * Log an info message
     * Used for general information about application operation.
     */
    info(message: string, context?: string, metadata?: LogMetadata): void;
    /**
     * Log a warning message
     * Used for potentially problematic situations that don't prevent operation
     */
    warn(message: string, context?: string, metadata?: LogMetadata): void;
    /**
     * Log an error message
     * Used for error events that might still allow the application to continue.
     */
    error(message: string, context?: string, metadata?: LogMetadata): void;
    /**
     * Create a child logger with a specific context
     */
    child(context: string): ContextLogger;
    /**
     * Get current logger configuration
     */
    getConfig(): LoggerConfig;
}
/**
 * Context logger that automatically includes context information.
 */
export declare class ContextLogger {
    private logger;
    private context;
    constructor(logger: Logger, context: string);
    debug(message: string, metadata?: LogMetadata): void;
    info(message: string, metadata?: LogMetadata): void;
    warn(message: string, metadata?: LogMetadata): void;
    error(message: string, metadata?: LogMetadata): void;
    child(childContext: string): ContextLogger;
}
export declare const defaultLogger: Logger;
export declare const debug: (message: string, context?: string, metadata?: LogMetadata) => void;
export declare const info: (message: string, context?: string, metadata?: LogMetadata) => void;
export declare const warn: (message: string, context?: string, metadata?: LogMetadata) => void;
export declare const error: (message: string, context?: string, metadata?: LogMetadata) => void;
export declare const fetchLogger: ContextLogger;
export declare const gtInstanceLogger: ContextLogger;
export { Logger as GTLogger };