feat: begin defer chapter

apps/34-signal/src/app/core/store/store.ts

@@ -0,0 +1,37 @@
+import { computed, inject, InjectionToken, makeEnvironmentProviders, signal } from '@angular/core';
+import { PeopleService } from '../providers/people.service';
+import { People, PeopleForm } from '../../shared/models/people.model';
+import { switchMap, tap } from 'rxjs';
+
+const filterPeople = (search: string) => (people: People) =>
+  people.lastname.toLowerCase().includes(search.toLowerCase()) || people.firstname.toLowerCase().includes(search.toLowerCase());
+
+function appStore(peopleService = inject(PeopleService)) {
+  const people = signal<People[]>([]);
+  const search = signal<string>('');
+
+  return {
+    people: computed(() => people().filter(filterPeople(search()))),
+    search: search.asReadonly(),
+    setSearch(value: string) {
+      search.set(value);
+    },
+    getPeople() {
+      return peopleService.getPeople().pipe(tap(data => people.set(data)));
+    },
+    deletePeople(id: string) {
+      return peopleService.deletePeople(id).pipe(tap(data => people.set(data)));
+    },
+    addNewPerson(person: PeopleForm) {
+      return peopleService.addNewPerson(person).pipe(switchMap(() => this.getPeople()));
+    },
+  };
+}
+
+export const PEOPLE_STORE = new InjectionToken<Store>('StoreToken');
+
+export type Store = ReturnType<typeof appStore>;
+
+export const provideAppStore = () => {
+  return makeEnvironmentProviders([{ provide: PEOPLE_STORE, useFactory: appStore }]);
+};