import type { ID } from '../../../types';
import { DagreGraph } from '../graph';

/**
 * TODO: The median method consistently performs better than the barycenter method and has a slight theoretical advantage
 */
export const barycenter = (g: DagreGraph, movable: ID[]) => {
  return movable.map((v) => {
    const inV = g.getRelatedEdges(v, 'in');
    if (!inV?.length) {
      return { v };
    }

    const result = { sum: 0, weight: 0 };
    inV?.forEach((e) => {
      const nodeU = g.getNode(e.source)!;
      result.sum += e.data.weight! * nodeU.data.order!;
      result.weight += e.data.weight!;
    });
    return {
      v,
      barycenter: result.sum / result.weight,
      weight: result.weight,
    };
  });
};