ecsy/lib/QueryManager.js

Entity Component System in JS

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _Query = _interopRequireDefault(require("./Query.js"));

var _Utils = require("./Utils.js");

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

/**
 * @private
 * @class QueryManager
 */
class QueryManager {
  constructor(world) {
    this._world = world; // Queries indexed by a unique identifier for the components it has

    this._queries = {};
  }

  onEntityRemoved(entity) {
    for (var queryName in this._queries) {
      var query = this._queries[queryName];

      if (entity.queries.indexOf(query) !== -1) {
        query.removeEntity(entity);
      }
    }
  }
  /**
   * Callback when a component is added to an entity
   * @param {Entity} entity Entity that just got the new component
   * @param {Component} Component Component added to the entity
   */


  onEntityComponentAdded(entity, Component) {
    // @todo Use bitmask for checking components?
    // Check each indexed query to see if we need to add this entity to the list
    for (var queryName in this._queries) {
      var query = this._queries[queryName];

      if (!!~query.NotComponents.indexOf(Component) && ~query.entities.indexOf(entity)) {
        query.removeEntity(entity);
        continue;
      } // Add the entity only if:
      // Component is in the query
      // and Entity has ALL the components of the query
      // and Entity is not already in the query


      if (!~query.Components.indexOf(Component) || !query.match(entity) || ~query.entities.indexOf(entity)) continue;
      query.addEntity(entity);
    }
  }
  /**
   * Callback when a component is removed from an entity
   * @param {Entity} entity Entity to remove the component from
   * @param {Component} Component Component to remove from the entity
   */


  onEntityComponentRemoved(entity, Component) {
    for (var queryName in this._queries) {
      var query = this._queries[queryName];

      if (!!~query.NotComponents.indexOf(Component) && !~query.entities.indexOf(entity) && query.match(entity)) {
        query.addEntity(entity);
        continue;
      }

      if (!!~query.Components.indexOf(Component) && !!~query.entities.indexOf(entity) && !query.match(entity)) {
        query.removeEntity(entity);
        continue;
      }
    }
  }
  /**
   * Get a query for the specified components
   * @param {Component} Components Components that the query should have
   */


  getQuery(Components) {
    var key = (0, _Utils.queryKey)(Components);
    var query = this._queries[key];

    if (!query) {
      this._queries[key] = query = new _Query.default(Components, this._world);
    }

    return query;
  }
  /**
   * Return some stats from this class
   */


  stats() {
    var stats = {};

    for (var queryName in this._queries) {
      stats[queryName] = this._queries[queryName].stats();
    }

    return stats;
  }

}

exports.default = QueryManager;