import * as I from 'immutable';

import {EntityList} from '@avocado/entity';
import {Tiles} from '@avocado/topdown';

export class Layer {

  constructor() {
    this.tiles = undefined;
    this.tilesetUri = undefined;
    this.entityList = new EntityList();
    this._state = I.Map();
  }

  fromJSON(json) {
    if (json.tiles) {
      this.tiles = (new Tiles()).fromJSON(json.tiles)
    }
    if (json.tilesetUri) {
      this.tilesetUri = json.tilesetUri;
    }
    return this;
  }

  get state() {
    return this._state;
  }

  tick(elapsed) {
    if (this.entityList) {
      this.entityList.tick(elapsed);
      this._state = this._state.set('entityList', this.entityList.state);
    }
  }

}