import { Seconds } from '@thermopylae/core.declarations';
import { GarbageCollector } from '../../garbage-collectors/interface';
import { AbstractExpirationPolicy, ExpirableCacheEntry } from './abstract';
import { EntryValidity } from '../../contracts/cache-replacement-policy';
/**
 * @private
 */
declare const TIME_SPAN_SYM: unique symbol;
/**
 * @private
 */
interface ExpirableSlidingCacheEntry<Key, Value> extends ExpirableCacheEntry<Key, Value> {
    [TIME_SPAN_SYM]?: Seconds;
}
interface SlidingExpirationPolicyArgsBundle {
    /**
     * Time span identifies how long the data should remain in the cache
     * after the data was last accessed.
     */
    timeSpan?: Seconds;
}
/**
 * Expiration policy which evicts keys based on time span access. <br/>
 * If key wasn't accessed in the specified {@link SlidingExpirationPolicyArgsBundle.timeSpan},
 * it will be evicted by {@link GarbageCollector} in the background. <br/>
 * If key was accessed in that time span, it's expiration time will be increased with the value of time span.
 *
 * @template Key				Type of the key.
 * @template Value				Type of the value.
 * @template ArgumentsBundle	Type of the arguments bundle.
 */
declare class SlidingProactiveExpirationPolicy<Key, Value, ArgumentsBundle extends SlidingExpirationPolicyArgsBundle = SlidingExpirationPolicyArgsBundle> extends AbstractExpirationPolicy<Key, Value, ArgumentsBundle> {
    /**
     * @private
     */
    private readonly gc;
    constructor(gc?: GarbageCollector<any>);
    /**
     * Get the number of tracked for expiration keys.
     */
    get size(): number;
    /**
     * Check whether GC is idle.
     */
    get idle(): boolean;
    /**
     * @inheritDoc
     */
    onHit(entry: ExpirableSlidingCacheEntry<Key, Value>): EntryValidity;
    /**
     * @inheritDoc
     */
    onSet(entry: ExpirableSlidingCacheEntry<Key, Value>, options?: ArgumentsBundle): void;
    /**
     * @inheritDoc
     */
    onUpdate(entry: ExpirableSlidingCacheEntry<Key, Value>, options?: ArgumentsBundle): void;
    /**
     * @inheritDoc
     */
    onDelete(entry: ExpirableSlidingCacheEntry<Key, Value>): void;
    /**
     * @inheritDoc
     */
    onClear(): void;
    private scheduleEviction;
    private static storeExpirationMetadata;
    private static isNonExpirable;
}
export { SlidingProactiveExpirationPolicy, ExpirableSlidingCacheEntry, SlidingExpirationPolicyArgsBundle, TIME_SPAN_SYM };