import { EntitySubscriberInterface, InsertEvent } from 'typeorm';
import DBSubmission from "./db-submission";
import DBComment from "./db-comment";
import { DBEntity } from "./db-entity";
import { DBPost } from "../db";
import DBUrl from "./db-url";
import { DownloadProgress } from "../../util/state";
export default class DBDownload extends DBEntity {
    id: number;
    /**
     * By default, a random UUID. If more URLs are located during processing, they should inherit this ID.
     */
    albumID: string | null;
    isAlbumParent: boolean;
    parentSubmission: Promise<DBSubmission>;
    parentComment: Promise<DBComment>;
    url: DBUrl;
    progress?: DownloadProgress;
    getDBParent(): Promise<DBPost>;
    /**
     * Creates/Finds a DBDownload instance, using the given URL (and optionally album).
     *
     * The returned Downloads will always be backed by a single global DBUrl+DBFile,
     * but the DBDownload itself may be new - and exists per-album.
     *
     * Does not save automatically.
     */
    static getDownloader(post: DBPost, url: string, albumID?: string): Promise<DBDownload>;
}
/**
 * Subscribable static emitter for all new, *unprocessed* DBDownloads.
 * Emits after each DBDownload is saved to the database.
 */
export declare class DownloadSubscriber implements EntitySubscriberInterface<DBDownload> {
    private static waiting;
    listenTo(): typeof DBDownload;
    afterInsert(event: InsertEvent<DBDownload>): void;
    /**
     * Wait for a new *unprocessed* DBUrl to be saved. Hands out new entities in the order that they were requested.
     *
     * Will only return `undefined` when {@link flush} is called.
     */
    static awaitNew(): Promise<DBDownload | undefined>;
    /**
     * Return `undefined` to all pending listeners.
     */
    static flush(): void;
}