/* Copyright CloudLinux Zug GmbH 2010-2017 All Rights Reserved
 *
 * Licensed under CLOUD LINUX LICENSE AGREEMENT
 * http://cloudlinux.com/docs/LICENSE.TXT
 */

import { Injectable } from '@angular/core';
import {Subject} from 'rxjs/Subject';
import {Observable} from 'rxjs/Observable';

export type InternalStateType = {
  [key: string]: any
};

@Injectable()
export class AppState {
  _state: InternalStateType = { };

  public onChange: Observable<any>;
  private changeEvent = new Subject<any>();

  constructor() {
        this.onChange = this.changeEvent.asObservable();
  }

  // already return a clone of the current state
  get state() {
    return this._state = this._clone(this._state);
  }
  // never allow mutation
  set state(value) {
    throw new Error('do not mutate the `.state` directly');
  }


  get(prop?: any) {
    // use our state getter for the clone
    const state = this.state;
    return state.hasOwnProperty(prop) ? state[prop] : state;
  }

  set(prop: string, value: any) {
    // internally mutate our state
    this._state[prop] = value;
    this.changeEvent.next();
  }


  private _clone(object: InternalStateType) {
    // simple object clone
    return JSON.parse(JSON.stringify( object ));
  }
}