import { ApiClient } from "@lodestar/api";
import { BeaconConfig } from "@lodestar/config";
import { Root, RootHex, Slot } from "@lodestar/types";
import { Logger } from "@lodestar/utils";
import { ValidatorEventEmitter } from "./emitter.js";
export type HeadEventData = {
    slot: Slot;
    head: RootHex;
    previousDutyDependentRoot: RootHex;
    currentDutyDependentRoot: RootHex;
};
export type ExecutionPayloadAvailableEventData = {
    slot: Slot;
    blockRoot: RootHex;
};
type RunEveryFn = (event: HeadEventData) => Promise<void>;
/**
 * Track the head slot/root using the event stream api "head".
 */
export declare class ChainHeaderTracker {
    private readonly config;
    private readonly logger;
    private readonly api;
    private readonly emitter;
    private headBlockSlot;
    private headBlockRoot;
    private readonly fns;
    constructor(config: BeaconConfig, logger: Logger, api: ApiClient, emitter: ValidatorEventEmitter);
    start(signal: AbortSignal): void;
    getCurrentChainHead(slot: Slot): Root | null;
    runOnNewHead(fn: RunEveryFn): void;
    private onEvent;
}
export {};
//# sourceMappingURL=chainHeaderTracker.d.ts.map