/**
 * Print Statistics Service
 *
 * Tracks and aggregates print job statistics including success rates,
 * performance metrics, and breakdowns by date/driver.
 *
 * @example
 * ```typescript
 * const stats = new PrintStatistics();
 * stats.trackJobStart('job-1', { driver: 'EscPos' });
 * stats.trackJobComplete('job-1', 1024, 500);
 * const report = stats.getStatistics();
 * const json = stats.exportToJSON();
 * ```
 */
/**
 * Print statistics data interface (returned by getStatistics)
 */
export interface PrintStatisticsData {
    /** Total jobs submitted */
    totalJobs: number;
    /** Successfully completed jobs */
    completedJobs: number;
    /** Failed jobs */
    failedJobs: number;
    /** Cancelled jobs */
    cancelledJobs: number;
    /** Total bytes printed */
    totalBytes: number;
    /** Average print time in milliseconds */
    averagePrintTime: number;
    /** Success rate (0-1) */
    successRate: number;
    /** Breakdown by date (YYYY-MM-DD) */
    byDate: Record<string, {
        completed: number;
        failed: number;
    }>;
    /** Breakdown by driver name */
    byDriver: Record<string, {
        completed: number;
        failed: number;
    }>;
}
/**
 * Job tracking metadata
 */
export interface JobTrackingMeta {
    /** Driver name */
    driver?: string;
    /** Device ID */
    deviceId?: string;
    /** Device name */
    deviceName?: string;
    /** Priority */
    priority?: number;
    /** Additional metadata */
    [key: string]: unknown;
}
/**
 * Internal job record
 */
interface JobRecord {
    id: string;
    status: 'started' | 'completed' | 'failed' | 'cancelled';
    startedAt: number;
    completedAt?: number;
    bytes?: number;
    duration?: number;
    error?: string;
    driver?: string;
    deviceId?: string;
    deviceName?: string;
    metadata?: Record<string, unknown>;
}
/**
 * Print Statistics Service
 *
 * Collects and aggregates print job metrics for analytics and monitoring.
 * Provides breakdown by date and driver for detailed reporting.
 */
export declare class PrintStatistics {
    private readonly logger;
    /** Internal job records map */
    private readonly jobs;
    /** Statistics counters */
    private totalJobs;
    private completedJobs;
    private failedJobs;
    private cancelledJobs;
    private totalBytes;
    private totalPrintTime;
    /** Date-based breakdown: YYYY-MM-DD -> { completed, failed } */
    private byDate;
    /** Driver-based breakdown: driverName -> { completed, failed } */
    private byDriver;
    /**
     * Track a job start event
     *
     * @param jobId - Unique job identifier
     * @param metadata - Optional job metadata (driver, device info, etc.)
     */
    trackJobStart(jobId: string, metadata?: JobTrackingMeta): void;
    /**
     * Track a job completion event
     *
     * @param jobId - Unique job identifier
     * @param bytes - Number of bytes printed
     * @param duration - Print duration in milliseconds
     */
    trackJobComplete(jobId: string, bytes: number, duration: number): void;
    /**
     * Track a job failure event
     *
     * @param jobId - Unique job identifier
     * @param error - Error message or error object
     */
    trackJobFail(jobId: string, error: unknown): void;
    /**
     * Track a job cancellation event
     *
     * @param jobId - Unique job identifier
     */
    trackJobCancel(jobId: string): void;
    /**
     * Get current statistics
     *
     * @returns Complete statistics object
     */
    getStatistics(): PrintStatisticsData;
    /**
     * Export statistics as JSON string
     *
     * @param pretty - Whether to format with indentation (default: true)
     * @returns JSON string representation
     */
    exportToJSON(pretty?: boolean): string;
    /**
     * Import statistics from JSON string
     *
     * @param json - JSON string to import
     * @returns Number of records imported
     */
    importFromJSON(json: string): number;
    /**
     * Get statistics for a specific date range
     *
     * @param startDate - Start date (timestamp or Date)
     * @param endDate - End date (timestamp or Date)
     * @returns Filtered statistics
     */
    getStatisticsByDateRange(startDate: Date | number, endDate: Date | number): PrintStatisticsData;
    /**
     * Get breakdown by date
     *
     * @returns Date-based breakdown object
     */
    getByDate(): Record<string, {
        completed: number;
        failed: number;
    }>;
    /**
     * Get breakdown by driver
     *
     * @returns Driver-based breakdown object
     */
    getByDriver(): Record<string, {
        completed: number;
        failed: number;
    }>;
    /**
     * Reset all statistics
     */
    reset(): void;
    /**
     * Get job record by ID
     *
     * @param jobId - Job identifier
     * @returns Job record or undefined
     */
    getJobRecord(jobId: string): JobRecord | undefined;
    private formatDateKey;
    private formatError;
    private aggregateByDate;
    private aggregateByDriver;
    /**
     * Generic aggregation helper. Groups jobs by a key function and counts
     * completed/failed per group. Skips jobs whose key is null/undefined.
     */
    private aggregateByKey;
    /**
     * Update driver and date breakdown stats for a job record.
     * Shared by trackJobComplete and trackJobFail.
     */
    private incrementBreakdownStats;
}
/** Singleton instance for convenience */
export declare const printStatistics: PrintStatistics;
export {};