import { DataFrame } from '../../data';
import { FrameMergeNode } from './FrameMergeNode';
import { MergeShapeOptions } from './MergeShape';

/**
 * Source merge node. This node merges the data frames from multiple sources into one.
 *
 * ## Usage
 * Merging is done by determining the incoming edges, once the amount of received frames from unique sources is
 * the same as the incoming edges, the frames are merged and pushed.
 *
 * It is possible to set a timeout, when this timeout is reached the frames that are received are merged and pushed.
 *
 * When frames of the same source are received they are overridden.
 * @rdf {@link http://purl.org/poso/HighLevelFusion}
 * @category Flow shape
 */
export class SourceMergeNode<InOut extends DataFrame> extends FrameMergeNode<InOut> {
    constructor(options?: MergeShapeOptions) {
        super(
            (frame: InOut) => {
                if (frame.source === undefined) {
                    return null;
                }
                return frame.source.uid;
            },
            (frame: InOut) => frame.uid,
            options,
        );
    }
}