import type { AnyActivityDefinition } from '../types.ts';
import { type EngineCleanupIntervalDisposalTracker } from './engine-leak-warnings.ts';
import type { Engine } from './index.ts';
import { type EngineInternals } from './internals.ts';
import type { SecondInstanceDetector } from './second-instance-detector.ts';
export declare function isActivityDefinition(value: unknown): value is AnyActivityDefinition;
type EngineCreateBackgroundTaskOptions = {
    backgroundTasks?: 'automatic' | 'manual' | undefined;
    recover?: boolean | undefined;
    startScheduler?: boolean | undefined;
};
export declare function validateEngineCreateBackgroundTaskOptions(options: EngineCreateBackgroundTaskOptions): void;
export declare function shouldStartEngineScheduler(options: EngineCreateBackgroundTaskOptions, backgroundTaskMode: 'automatic' | 'manual'): boolean;
export declare function createQueuedInlineWorkflowStartHandler<TWorkflows extends object, TActivities extends object>(weakEngine: WeakRef<Engine<TWorkflows, TActivities>>, channel: MessageChannel): () => void;
/**
 * Drain pending inline launches for `engine` before teardown. Built with the
 * same inline-launch-queue callbacks as the scheduled flush handler so a drained
 * start advances identically to a normally-flushed one. Called from
 * `[Symbol.asyncDispose]` ahead of synchronous disposal (which aborts the signal
 * and would otherwise discard the queue).
 */
export declare function drainQueuedInlineWorkflowStartsForEngine<TWorkflows extends object, TActivities extends object>(engine: Engine<TWorkflows, TActivities>, options?: {
    abortStartedWorkflows?: boolean;
}): Promise<void>;
export declare function createCleanupIntervalTick<TWorkflows extends object, TActivities extends object>(weakEngine: WeakRef<Engine<TWorkflows, TActivities>>, tracker: EngineCleanupIntervalDisposalTracker): () => void;
/**
 * Build the resolver the second-instance detection interval uses to find its live
 * detector. Returns `null` when the engine has been garbage-collected or disposed
 * (so the tick is skipped), otherwise the engine's current detector. Extracted
 * here — like {@link createCleanupIntervalTick} — so the deref/disposed guard is
 * directly testable without driving a real interval.
 */
export declare function createSecondInstanceDetectorResolver<TWorkflows extends object, TActivities extends object>(weakEngine: WeakRef<Engine<TWorkflows, TActivities>>): () => SecondInstanceDetector | null;
export declare function disposeEngineCleanupInterval(internals: EngineInternals): void;
export {};