/**
 * Structured logging utility for cache operations
 *
 * Provides structured logging with log levels (INFO, DEBUG, WARN, ERROR)
 * and support for metrics (counts, durations, etc.)
 *
 * @module cache-logger
 */
/**
 * Log levels
 */
export declare enum LogLevel {
    DEBUG = 0,
    INFO = 1,
    WARN = 2,
    ERROR = 3
}
/**
 * Log entry structure
 */
export interface LogEntry {
    level: LogLevel;
    message: string;
    context?: string;
    metrics?: Record<string, number | string | boolean>;
    error?: Error;
    timestamp: number;
}
/**
 * Structured logger for cache operations
 */
declare class CacheLogger {
    private config;
    private readonly debugMode;
    constructor();
    /**
     * Logs a message with the specified level
     */
    private log;
    /**
     * Logs to console in a human-readable format (backward compatible)
     */
    private logToConsole;
    /**
     * Logs structured output (JSON format)
     */
    private logStructured;
    /**
     * Determines if structured logging should be used for this level
     */
    private shouldLogStructured;
    /**
     * Logs a DEBUG message
     */
    debug(message: string, context?: string, metrics?: Record<string, any>): void;
    /**
     * Logs an INFO message with optional metrics
     */
    info(message: string, context?: string, metrics?: Record<string, any>): void;
    /**
     * Logs a WARN message
     */
    warn(message: string, context?: string, metrics?: Record<string, any>): void;
    /**
     * Logs an ERROR message
     */
    error(message: string, context?: string, metrics?: Record<string, any>, error?: Error): void;
}
export declare const cacheLogger: CacheLogger;
export {};