drawing-board/src/board/core/base/entity-group.ts

import { Group } from "konva/lib/Group";
import {
  Entity,
  EntityProps,
  EntityShape,
  EntityTree,
  EntityType,
} from "./entity";
import { IncEntitysFactory, incEntitysFactoryGenerate } from "./entity-factory";

type Data<T extends EntityType> = T extends EntityType<infer D> ? D : never;

export class EntityGroup<
  T extends EntityType<any, EntityShape, EntityTree<any, any>>
> extends Entity<
  Data<T>[],
  Group,
  EntityTree<EntityGroup<T>, InstanceType<T>>
> {
  private incFactory: IncEntitysFactory<EntityGroup<T>, Data<T>, T>;

  constructor({ type, ...props }: EntityProps<Data<T>[]> & { type: T }) {
    super(props);
    this.incFactory = incEntitysFactoryGenerate(type, this as EntityGroup<T>);
    this.diffRedraw();
  }

  diffRedraw() {
    const { adds } = this.incFactory(this.attrib);

    adds.forEach((add) => {
      add.bus.on("destroyed", () => {
        const ndx = this.attrib.indexOf(add.attrib);
        if (~ndx) {
          this.attrib.splice(ndx, 1);
        }
      });
      add.bus.on("updateAttrib", ([newAttrib, oldAttrib]) => {
        const ndx = this.attrib.indexOf(oldAttrib);
        if (~ndx) {
          this.attrib[ndx] = newAttrib;
        }
      });
    });
  }

  addItem(data: Data<T>) {
    this.attrib.push(data);
    this.diffRedraw();
  }

  delItem(data: Data<T>) {
    const ndx = this.attrib.indexOf(data);
    if (~ndx) {
      this.attrib.splice(ndx, 1);
      this.diffRedraw();
    }
  }
}