silphius/app/ecs/system.js

import Query from './query.js';

export default class System {

  active = false;

  destroying = [];

  ecs;

  queries = {};

  constructor(ecs) {
    this.ecs = ecs;
    const queries = this.constructor.queries();
    for (const i in queries) {
      this.queries[i] = new Query(queries[i], ecs.Components);
    }
    this.reindex(ecs.entities);
  }

  createEntity(components) {
    return this.ecs.create(components);
  }

  createManyEntities(componentsList) {
    return this.ecs.createMany(componentsList);
  }

  deindex(entityIds) {
    for (const i in this.queries) {
      this.queries[i].deindex(entityIds);
    }
  }

  destroyEntity(entityId) {
    this.destroyManyEntities([entityId]);
  }

  destroyManyEntities(entityIds) {
    for (let i = 0; i < entityIds.length; i++) {
      this.destroying.push(entityIds[i]);
    }
  }

  finalize() {}

  insertComponents(entityId, components) {
    this.ecs.insert(entityId, components);
  }

  insertManyComponents(components) {
    this.ecs.insertMany(components);
  }

  static queries() {
    return {};
  }

  reindex(entityIds) {
    for (const i in this.queries) {
      this.queries[i].reindex(entityIds);
    }
  }

  removeComponents(entityId, components) {
    this.ecs.remove(entityId, components);
  }

  removeManyComponents(entityIds) {
    this.ecs.removeMany(entityIds);
  }

  select(query) {
    return this.queries[query].select();
  }

  tickDestruction() {
    this.deindex(this.destroying);
    this.destroying = [];
  }

  tick() {}

}