itayod

export interface State {
  theme: 'dark' | 'light';
}

itayod

export function metaReducer(reducer: ActionReducer<any>) : ActionReducer<any> {
  // a function with the exact same signature of a reducer
  return function(state: any, action: Action) {
    return reducer(state, action);
  };
}

itayod

import {ActionReducer, Action} from '@ngrx/store';
import {merge, pick} from 'lodash-es';

function setSavedState(state: any, localStorageKey: string) {
  localStorage.setItem(localStorageKey, JSON.stringify(state));
}
function getSavedState(localStorageKey: string): any {
  return JSON.parse(localStorage.getItem(localStorageKey));
}

itayod

import {StoreModule} from '@ngrx/store';
import {storageMetaReducer} from './storage.metareducer';

@NgModule({
  imports: [StoreModule.forRoot(
    reducers, 
    { 
      metaReducers: [storageMetaReducer] 
    }
  )]

itayod

import {InjectionToken} from '@angular/core';

// token for the state keys.
export const ROOT_STORAGE_KEYS = new InjectionToken<string[]>('StoreKeys');
// token for the localStorage key.
export const ROOT_LOCAL_STORAGE_KEY = new InjectionToken<string[]>('appStorage');

itayod

import {Injectable} from '@angular/core';

@Injectable( { providedIn: 'root' } )
export class LocalStorageService {
  constructor() {}

  setSavedState(state: any, localStorageKey: string) {
    localStorage.setItem(localStorageKey, JSON.stringify(state));
  }

itayod

import {StoreModule, MetaReducer, META_REDUCERS} from '@ngrx/store';
import {ROOT_STORAGE_KEYS, LOCAL_STORAGE_KEY} from './app.tokens';
import {LocalStorageService} from './shared/local-storage.service';
import {storageMetaReducer} from './storage.metareducer';

// factory meta-reducer configuration function
export function getMetaReducers(saveKeys: string[],
                                 localStorageKey: string,
                                 storageService: LocalStorageService
                                ): MetaReducer<any>[] {

itayod

import {ActionReducer, Action} from '@ngrx/store';
import {merge, pick} from 'lodash-es';
import {LocalStorageService} from './local-storage.service';

export function storageMetaReducer<S, A extends Action = Action>(saveKeys: string[],
                                                                  localStorageKey: string,
                                                                  storageService: LocalStorageService
                                                                 ) {
  let onInit = true; // after load/refresh…
  return function(reducer: ActionReducer<S, A>) {

itayod

export enum ViewModes {
  SingleCol = 'SINGLE',
  MultiCol = 'MULTI',
}

export interface Course {
  id: number;
  description?: string;
  iconUrl?: string;
  courseListIcon?: string;

itayod

import {InjectionToken} from '@angular/core';
import {StoreConfig} from '@ngrx/store/src/store_module';
import * as fromReducer from './reducers/courses.reducer';
import * as fromActions from './actions/courses.actions';

export const COURSES_STORAGE_KEYS = 
  new InjectionToken<keyof fromReducer.State[]>('CoursesStorageKeys');
export const COURSES_LOCAL_STORAGE_KEY =
  new InjectionToken<string[]>('CoursesStorage');
export const COURSES_CONFIG_TOKEN =