@openhps/core/dist/cjs/three/renderers/common/ChainMap.js

Open Hybrid Positioning System - Core component

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
/**
 * Data structure for the renderer. It allows defining values
 * with chained, hierarchical keys. Keys are meant to be
 * objects since the module internally works with Weak Maps
 * for performance reasons.
 *
 * @private
 */
class ChainMap {
  /**
   * Constructs a new Chain Map.
   */
  constructor() {
    /**
     * The root Weak Map.
     *
     * @type {WeakMap}
     */
    this.weakMap = new WeakMap();
  }

  /**
   * Returns the value for the given array of keys.
   *
   * @param {Array<Object>} keys - List of keys.
   * @return {any} The value. Returns `undefined` if no value was found.
   */
  get(keys) {
    let map = this.weakMap;
    for (let i = 0; i < keys.length - 1; i++) {
      map = map.get(keys[i]);
      if (map === undefined) return undefined;
    }
    return map.get(keys[keys.length - 1]);
  }

  /**
   * Sets the value for the given keys.
   *
   * @param {Array<Object>} keys - List of keys.
   * @param {any} value - The value to set.
   * @return {ChainMap} A reference to this Chain Map.
   */
  set(keys, value) {
    let map = this.weakMap;
    for (let i = 0; i < keys.length - 1; i++) {
      const key = keys[i];
      if (map.has(key) === false) map.set(key, new WeakMap());
      map = map.get(key);
    }
    map.set(keys[keys.length - 1], value);
    return this;
  }

  /**
   * Deletes a value for the given keys.
   *
   * @param {Array<Object>} keys - The keys.
   * @return {boolean} Returns `true` if the value has been removed successfully and `false` if the value has not be found.
   */
  delete(keys) {
    let map = this.weakMap;
    for (let i = 0; i < keys.length - 1; i++) {
      map = map.get(keys[i]);
      if (map === undefined) return false;
    }
    return map.delete(keys[keys.length - 1]);
  }
}
var _default = exports.default = ChainMap;