/**
 * Time-bucketed aggregation for log10x_backfill_metric.
 *
 * Takes a list of events (from the Retriever) and produces a time-series
 * of `(timestamp, labels, value)` points suitable for emission to a TSDB.
 *
 * Aggregation types:
 *   count             — number of events in the bucket
 *   sum_bytes         — total byte size of events in the bucket
 *   unique_values     — cardinality of a named dimension in the bucket
 *   rate_per_second   — events per second (count / bucket_seconds)
 *
 * Grouping dimensions come from the Retriever event's `enrichedFields`
 * (severity, service, tenant_id, http_code, ...). If the caller passes a
 * group_by that is not present on any event, the aggregator treats the
 * dimension as an empty string so the caller still gets a single series
 * rather than a silent drop.
 */
import type { RetrieverEvent } from './retriever-api.js';
export type AggregationType = 'count' | 'sum_bytes' | 'unique_values' | 'rate_per_second';
export interface AggregatorOptions {
    bucketSize: string;
    aggregation: AggregationType;
    /** Fields to group on — each combination becomes its own time series. */
    groupBy?: string[];
    /** For unique_values aggregation: the field whose cardinality is counted per bucket. */
    uniqueField?: string;
}
export interface MetricPoint {
    /** UNIX seconds since epoch. */
    timestamp: number;
    /** Labels identifying the time series. */
    labels: Record<string, string>;
    value: number;
}
export interface AggregatedSeries {
    points: MetricPoint[];
    seriesCount: number;
    bucketSeconds: number;
    eventCount: number;
}
export declare function aggregate(events: RetrieverEvent[], options: AggregatorOptions): AggregatedSeries;
/** Parse `5m` / `1h` / `1d` into seconds. */
export declare function parseBucketSize(s: string): number;