Class NodeManager

packages/react/src/renderer/NodeManager/NodeManager.ts:22–316

export type Node = SparseNode | PopulatedNode;

export class NodeManager {
  public root: PopulatedNode;

  private references = new Map<string, PopulatedNode>();
  private subscribers = new Set<() => void>();

  constructor(source: Node) {
    this.root = this.populate(source);
  }

  public find = (id: string): PopulatedNode | undefined => {
    return this.references.get(id);
  };

  public insert = (node: Node, destination: { id: string; index: number }) => {
    const child = 'id' in node ? (node as PopulatedNode) : this.populate(node);
    const parent = this.find(destination.id);

    if (!parent) {
      return;
    }

    child.parent = parent.id;
    parent.children = [
      ...parent.children.slice(0, destination.index),
      child,
      ...parent.children.slice(destination.index),
    ];

    this.notify();

    return child.id;
  };

  public remove = (id: string, permanent = true) => {
    const node = this.find(id);

    if (!node) {
      throw new Error(`Node with id ${id} not found`);
    }

    if (!node.parent) {
      throw new Error('Cannot remove root node');
    }

    const parent = this.find(node.parent);

    if (!parent) {
      throw new Error('Parent node not found');
    }

    parent.children = parent.children.filter((child) => typeof child === 'string' || child.id !== id);

    if (node.implicit.parentPropKey) {
      parent.props[node.implicit.parentPropKey] = null;
      delete parent.implicit.children[node.implicit.parentPropKey];
      delete node.implicit.parentPropKey;
    }