import { LogEntry, LogLevel, LogMiddleware, MiddlewareContext } from '../types';
export interface LogMetrics {
    totalLogs: number;
    logsByLevel: Record<LogLevel, number>;
    errorCount: number;
    averageLogSize: number;
    lastLogTime: Date | null;
    logFrequency: number;
}
export declare class MetricsMiddleware implements LogMiddleware {
    private options;
    readonly name = "MetricsMiddleware";
    private metrics;
    private logHistory;
    private totalLogSize;
    constructor(options?: {
        trackFrequency?: boolean;
        frequencyWindowMinutes?: number;
    });
    execute(entry: LogEntry, context: MiddlewareContext, next: () => Promise<void> | void): Promise<void>;
    private updateLogFrequency;
    getMetrics(): LogMetrics;
    resetMetrics(): void;
}