/**
 * SMTP Logging Utilities
 * Provides structured logging for SMTP server components
 */
import * as plugins from '../../../../plugins.js';
import { SecurityLogLevel, SecurityEventType } from '../constants.js';
import type { ISmtpSession } from '../interfaces.js';
/**
 * SMTP connection metadata to include in logs
 */
export interface IConnectionMetadata {
    remoteAddress?: string;
    remotePort?: number;
    socketId?: string;
    secure?: boolean;
    sessionId?: string;
}
/**
 * Log levels for SMTP server
 */
export type LogLevel = 'debug' | 'info' | 'warn' | 'error';
/**
 * Options for SMTP log
 */
export interface ISmtpLogOptions {
    level?: LogLevel;
    sessionId?: string;
    sessionState?: string;
    remoteAddress?: string;
    remotePort?: number;
    command?: string;
    error?: Error;
    [key: string]: any;
}
/**
 * SMTP logger - provides structured logging for SMTP server
 */
export declare class SmtpLogger {
    /**
     * Log a message with context
     * @param level - Log level
     * @param message - Log message
     * @param options - Additional log options
     */
    static log(level: LogLevel, message: string, options?: ISmtpLogOptions): void;
    /**
     * Log debug level message
     * @param message - Log message
     * @param options - Additional log options
     */
    static debug(message: string, options?: ISmtpLogOptions): void;
    /**
     * Log info level message
     * @param message - Log message
     * @param options - Additional log options
     */
    static info(message: string, options?: ISmtpLogOptions): void;
    /**
     * Log warning level message
     * @param message - Log message
     * @param options - Additional log options
     */
    static warn(message: string, options?: ISmtpLogOptions): void;
    /**
     * Log error level message
     * @param message - Log message
     * @param options - Additional log options
     */
    static error(message: string, options?: ISmtpLogOptions): void;
    /**
     * Log command received from client
     * @param command - The command string
     * @param socket - The client socket
     * @param session - The SMTP session
     */
    static logCommand(command: string, socket: plugins.net.Socket | plugins.tls.TLSSocket, session?: ISmtpSession): void;
    /**
     * Log response sent to client
     * @param response - The response string
     * @param socket - The client socket
     */
    static logResponse(response: string, socket: plugins.net.Socket | plugins.tls.TLSSocket): void;
    /**
     * Log client connection event
     * @param socket - The client socket
     * @param eventType - Type of connection event (connect, close, error)
     * @param session - The SMTP session
     * @param error - Optional error object for error events
     */
    static logConnection(socket: plugins.net.Socket | plugins.tls.TLSSocket, eventType: 'connect' | 'close' | 'error', session?: ISmtpSession, error?: Error): void;
    /**
     * Log security event
     * @param level - Security log level
     * @param type - Security event type
     * @param message - Log message
     * @param details - Event details
     * @param ipAddress - Client IP address
     * @param domain - Optional domain involved
     * @param success - Whether the security check was successful
     */
    static logSecurityEvent(level: SecurityLogLevel, type: SecurityEventType, message: string, details: Record<string, any>, ipAddress?: string, domain?: string, success?: boolean): void;
}
/**
 * Default instance for backward compatibility
 */
export declare const smtpLogger: typeof SmtpLogger;