import { Entity } from '../binding';
import { Node } from './Node';
import type { EntityManager } from '../EntityManager';
import { Class } from '../util';

/**
 * An Operator saves the state of a combined query
 */
export class Operator<T extends Entity> extends Node<T> {
  /**
   * The operator used to join the child queries
   */
  public readonly operator: string;

  /**
   * The child Node of this query, it is always one
   */
  public readonly childes: Node<T>[];

  /**
   * @param entityManager The owning entity manager of this query
   * @param resultClass The query result class
   * @param operator The operator used to join the childes
   * @param childes The childes to join
   */
  constructor(entityManager: EntityManager, resultClass: Class<T>, operator: string, childes: Node<T>[]) {
    super(entityManager, resultClass);
    this.operator = operator;
    this.childes = childes;
  }

  toJSON(): { [operator: string]: Node<T>[] } {
    const json: { [operator: string]: Node<T>[] } = {};
    json[this.operator] = this.childes;
    return json;
  }
}