import {quadtree} from 'd3-quadtree';

import * as Rectangle from './rectangle';

export class QuadTree {

  constructor() {
    this._visitNodes = [];
    this._queryRectangle = [0, 0, 0, 0];
    this.quadTree = quadtree();
    this.onVisit = this.onVisit.bind(this);
  }

  add(datum) {
    this.quadTree.add(datum);
  }

  clear() {
    const data = this.quadTree.data();
    for (let i = 0; i < data.length; i++) {
      const datum = data[i];
      this.quadTree.remove(datum);
    }
  }

  onVisit(node, x, y, x0, y0) {
    const w = x0 - x;
    const h = y0 - y;
    if (!Rectangle.intersects(this._queryRectangle, [x, y, w, h])) {
      return true;
    }
    if (4 === node.length) {
      return;
    }
    do {
      if (Rectangle.isTouching(this._queryRectangle, node.data)) {
        this.nodes.push(node);
      }
    } while (node = node.next);
  }

  remove(datum) {
    this.quadTree.remove(datum);
  }

  search(queryRectangle) {
    this._queryRectangle = queryRectangle;
    this.nodes = [];
    this.quadTree.visit(this.onVisit);
    return this.nodes;
  }

}