Start refactoring state management

src/app/services/data.service.ts

@@ -1,93 +1,69 @@
 import { Injectable } from '@angular/core';
 import { StoreService } from './store.service';
 import { Page } from '../model/page';
-
-const USER_DATA_KEY = 'life-towers.user-data.v.1';
+import { Root } from '../storage/root';
+import { Serializable } from '../model/serializable';
+import { Tower } from '../model/tower';
+import { Block } from '../model/block';
+import { IPage } from '../interfaces/persistance/page';
+import { BehaviorSubject } from 'rxjs/internal/BehaviorSubject';
+import { Observable } from 'rxjs/internal/Observable';
 
 @Injectable({
   providedIn: 'root'
 })
-export class DataService {
-  get active(): Page {
-    return this._active;
+export class DataService extends Root<Page> {
+  get pages(): Array<Page> {
+    return this.children;
   }
 
-  get pageNames(): string[] {
-    return this.data.map(p => p.name);
-  }
+  private readonly _safeChildren: BehaviorSubject<Array<Page>> = new BehaviorSubject(null);
+  readonly safeChildren$: Observable<Array<Page>> = this._safeChildren.asObservable();
 
-  private subscribers: (() => void)[] = [];
-  private _active: Page = null;
-  private data: Page[];
-  private hasLoaded = new Promise(resolve => (this.afterLoadFinished = resolve));
-  private afterLoadFinished: () => void;
-
-  constructor(private storeService: StoreService) {
-    this.init();
-  }
-
-  push(value: Page) {
-    value.subscribe(() => this.save());
-    this.data.push(value);
-    this._active = value;
-    this.save();
-  }
-
-  remove() {
-    this.data = this.data.filter(p => p !== this.active);
-    this._active = this.data.length > 0 ? this.data[0] : null;
-    this.save();
-  }
-
-  subscribe(func: () => void) {
-    this.subscribers.push(func);
-  }
-
-  async changeActiveByName(name: string): Promise<void> {
-    await this.hasLoaded;
-    this._active = this.data.filter(p => p.name === name)[0];
-    this.saveActiveIndex(this.data.indexOf(this.active));
-    this.update();
-  }
-
-  async changeActiveByIndex(index: number): Promise<void> {
-    await this.hasLoaded;
-    this._active = this.data[index];
-    this.saveActiveIndex(index);
-    this.update();
+  constructor(private storeService: StoreService<Array<IPage>>) {
+    super();
+    this.init().catch();
   }
 
   private async init() {
-    this.data = await this.storeService.load();
-    this.data.map(p => p.subscribe(() => this.save()));
-    this._active = this.data.length > 0 ? this.data[0] : null;
-    this.loadActiveIndex();
-    this.afterLoadFinished();
-  }
-
-  private save() {
-    this.storeService.save(this.data);
-    this.update();
-  }
-
-  private update() {
-    this.subscribers.map(f => f());
-  }
-
-  private loadActiveIndex() {
-    const userData = JSON.parse(window.localStorage.getItem(USER_DATA_KEY));
-    if (userData === null) {
-      return;
+    const pages = await this.storeService.load();
+    Serializable.childrenMap = {
+      Page: {
+        childrenListName: 'towers',
+        childrenConstructor: Tower
+      },
+      Tower: {
+        childrenListName: 'blocks',
+        childrenConstructor: Block
+      },
+      Block: {
+        childrenListName: null,
+        childrenConstructor: null
+      }
+    };
+    for (let page of pages) {
+      new Page(this, page);
     }
-    this._active = this.data[userData.index];
+    this.children$.subscribe(value => {
+      this.log();
+      this._safeChildren.next(value);
+      this.storeService.scheduleSave(this.pages);
+    });
   }
 
-  private saveActiveIndex(index: number) {
-    window.localStorage.setItem(
-      USER_DATA_KEY,
-      JSON.stringify({
-        index
-      })
-    );
+  addPage(name: string) {
+    new Page(this, {
+      name,
+      userData: {},
+      type: 'Page',
+      towers: []
+    });
+  }
+
+  removePage(page: Page) {
+    this.changeValue({
+      oldValue: this.children,
+      newValue: this.children.filter(c => c !== page)
+    });
   }
 }