import type { Event } from "../event.js";
import { Level } from "../level.js";
import type { SpanAttributes } from "../span.js";
import type { ISubscriber } from "../subscriber.js";
type SpanNode = {
    id: symbol;
    attributes: SpanAttributes;
};
type PendingSpanNode = SpanNode & {
    parent: undefined;
};
type EnteredSpanNode = SpanNode & {
    parent: EnteredSpanNode | undefined;
};
/**
 * The ManagedSubscriber class is a base class for subscribers which manage spans across async contexts. It exposes
 * an ergonomic high-level API which makes it easy to create custom subscribers.
 *
 * @example
 * ```ts
 * import { ManagedSubscriber, Event, SpanAttributes, setDefaultGlobalSubscriber } from "@bcheidemann/tracing";
 *
 * class MySubscriber extends ManagedSubscriber {
 *   public static init(): MySubscriber {
 *     const subscriber = new MySubscriber();
 *     // Enter the new subscriber into the current async context
 *     setDefaultGlobalSubscriber(subscriber);
 *     return subscriber;
 *   }
 *
 *   protected onEvent(event: Event, spans: SpanAttributes[]): void {
 *     console.log(event, spans);
 *   }
 * }
 * ```
 */
export declare abstract class ManagedSubscriber implements ISubscriber<symbol> {
    private readonly _level;
    private _currentSpan;
    private readonly _pendingSpans;
    protected constructor(_level?: Level, _currentSpan?: EnteredSpanNode | undefined, _pendingSpans?: WeakMap<symbol, PendingSpanNode>);
    enabledForLevel(level: Level): boolean;
    enabled(_metadata: Event | SpanAttributes): boolean;
    newSpan(attributes: SpanAttributes): symbol;
    event(event: Event): void;
    enter(span: symbol): void;
    exit(span: symbol): void;
    record(spanId: symbol, key: string, value: unknown): void;
    currentSpan(): symbol | undefined;
    clone(): ISubscriber<symbol>;
    runInContext<TThis, TArgs extends unknown[], TReturn>(callback: (this: TThis, ...args: TArgs) => TReturn, thisArg: TThis, args: TArgs): TReturn;
    protected abstract onEvent(event: Event, spans: SpanAttributes[]): void;
}
export {};
//# sourceMappingURL=ManagedSubscriber.d.ts.map