linker.js

class Linker {
  constructor(nodes, edges) {
    this.cache = new Cache(nodes, edges)
  }
  
  process(edges) {
    const nodes = this.link(this.findRootEdges(edges))
    Object.defineProperty(this, "nodes", {
      value: Object.freeze(nodes)
    })
  }
    
  link(edges) {
    return edges.map(edge => {
      edge.source = this.cache.node(edge.source.toString())
      edge.target = this.cache.node(edge.target.toString())

      this.link(this.cache.edgeFromSource(edge.target.id.toString()))
      return edge
    })
  }
}