import * as I from 'immutable';

import {Layer} from './layer';

export class Room {

  constructor() {
    this.layers = [];
    this._layersState = I.Map();
    this._state = I.Map();
  }

  fromJSON(json) {
    if (json.layers) {
      this.layers = json.layers.map((layerJSON) => {
        return (new Layer()).fromJSON(layerJSON);
      });
    }
    return this;
  }

  get state() {
    return this._state;
  }

  tick(elapsed) {
    for (let i = 0; i < this.layers.length; ++i) {
      const layer = this.layers[i];
      layer.tick(elapsed);
      this._layersState = this._layersState.set(i, layer.state);
    }
    this._state = this._state.set('layers', this._layersState);
  }

}