Answer:1 - Content Projection Refactor

apps/angular/1-projection/src/app/component/city-card/city-card.component.ts

@@ -1,9 +1,63 @@
-import { ChangeDetectionStrategy, Component } from '@angular/core';
+import { NgOptimizedImage } from '@angular/common';
+import { ChangeDetectionStrategy, Component, inject } from '@angular/core';
+import { CityStore } from '../../data-access/city.store';
+import {
+  FakeHttpService,
+  randomCity,
+} from '../../data-access/fake-http.service';
+import { CardType } from '../../model/card.model';
+import { CardComponent } from '../../ui/card/card.component';
+import { ListItemComponent } from '../../ui/list-item/list-item.component';
 
 @Component({
   selector: 'app-city-card',
-  template: 'TODO City',
-  imports: [],
+  template: `
+    <app-card [list]="cities()">
+      <div card-header class="flex flex-col items-center">
+        <img
+          ngSrc="assets/img/city.png"
+          width="200"
+          height="200"
+          alt="Cities list view banner"
+          priority />
+      </div>
+
+      <ng-template #itemTemplate let-item>
+        <app-list-item
+          [name]="item.name"
+          [id]="item.id"
+          [type]="cardType"
+          (emitDelete)="deleteSingle($event)" />
+      </ng-template>
+
+      <div card-action>
+        <button
+          class="rounded-sm border border-blue-500 bg-blue-300 p-2"
+          (click)="addNew()">
+          Add
+        </button>
+      </div>
+    </app-card>
+  `,
+  imports: [CardComponent, NgOptimizedImage, ListItemComponent],
   changeDetection: ChangeDetectionStrategy.OnPush,
 })
-export class CityCardComponent {}
+export class CityCardComponent {
+  readonly cityStore = inject(CityStore);
+  readonly http = inject(FakeHttpService);
+
+  cardType = CardType.CITY;
+  readonly cities = this.cityStore.cities;
+
+  ngOnInit(): void {
+    this.http.fetchCities$.subscribe((c) => this.cityStore.addAll(c));
+  }
+
+  addNew(): void {
+    this.cityStore.addOne(randomCity());
+  }
+
+  deleteSingle(id: number) {
+    this.cityStore.deleteOne(id);
+  }
+}

apps/angular/1-projection/src/app/component/student-card/student-card.component.ts

@@ -1,33 +1,62 @@
+import { NgOptimizedImage } from '@angular/common';
 import {
   ChangeDetectionStrategy,
   Component,
   inject,
   OnInit,
 } from '@angular/core';
-import { FakeHttpService } from '../../data-access/fake-http.service';
+import {
+  FakeHttpService,
+  randStudent,
+} from '../../data-access/fake-http.service';
 import { StudentStore } from '../../data-access/student.store';
 import { CardType } from '../../model/card.model';
 import { CardComponent } from '../../ui/card/card.component';
+import { ListItemComponent } from '../../ui/list-item/list-item.component';
 
 @Component({
   selector: 'app-student-card',
   template: `
-    <app-card
-      [list]="students()"
-      [type]="cardType"
-      customClass="bg-light-green" />
+    <app-card [list]="students()" customClass="bg-light-green">
+      <div card-header class="flex flex-col items-center">
+        <img
+          ngSrc="assets/img/student.webp"
+          width="200"
+          height="200"
+          alt="Students list view banner"
+          priority />
+      </div>
+
+      <ng-template #itemTemplate let-item>
+        <app-list-item
+          [name]="item.firstName"
+          [id]="item.id"
+          [type]="cardType"
+          (emitDelete)="deleteSingle($event)" />
+      </ng-template>
+
+      <div card-action>
+        <button
+          class="rounded-sm border border-blue-500 bg-blue-300 p-2"
+          (click)="addNew()">
+          Add
+        </button>
+      </div>
+    </app-card>
   `,
   styles: [
     `
-      ::ng-deep .bg-light-green {
-        background-color: rgba(0, 250, 0, 0.1);
+      :host {
+        --card-bg: rgba(0, 250, 0, 0.1);
       }
     `,
   ],
-  imports: [CardComponent],
+  imports: [CardComponent, NgOptimizedImage, ListItemComponent],
   changeDetection: ChangeDetectionStrategy.OnPush,
 })
 export class StudentCardComponent implements OnInit {
+  private readonly studentStore = inject(StudentStore);
+
   private http = inject(FakeHttpService);
   private store = inject(StudentStore);
 
@@ -37,4 +66,12 @@ export class StudentCardComponent implements OnInit {
   ngOnInit(): void {
     this.http.fetchStudents$.subscribe((s) => this.store.addAll(s));
   }
+
+  addNew(): void {
+    this.studentStore.addOne(randStudent());
+  }
+
+  deleteSingle(id: number): void {
+    this.studentStore.deleteOne(id);
+  }
 }

apps/angular/1-projection/src/app/component/teacher-card/teacher-card.component.ts

@@ -1,27 +1,51 @@
+import { NgOptimizedImage } from '@angular/common';
 import { Component, inject, OnInit } from '@angular/core';
-import { FakeHttpService } from '../../data-access/fake-http.service';
+import {
+  FakeHttpService,
+  randTeacher,
+} from '../../data-access/fake-http.service';
 import { TeacherStore } from '../../data-access/teacher.store';
 import { CardType } from '../../model/card.model';
 import { CardComponent } from '../../ui/card/card.component';
+import { ListItemComponent } from '../../ui/list-item/list-item.component';
 
 @Component({
   selector: 'app-teacher-card',
   template: `
-    <app-card
-      [list]="teachers()"
-      [type]="cardType"
-      customClass="bg-light-red"></app-card>
+    <app-card [list]="teachers()" customClass="bg-light-red">
+      <div card-header class="flex flex-col items-center">
+        <img ngSrc="assets/img/teacher.png" width="200" height="200" alt="" />
+      </div>
+
+      <ng-template #itemTemplate let-item>
+        <app-list-item
+          [name]="item.firstName"
+          [id]="item.id"
+          [type]="cardType"
+          (emitDelete)="deleteSingle($event)" />
+      </ng-template>
+
+      <div card-action>
+        <button
+          class="rounded-sm border border-blue-500 bg-blue-300 p-2"
+          (click)="addNew()">
+          Add
+        </button>
+      </div>
+    </app-card>
   `,
   styles: [
     `
-      ::ng-deep .bg-light-red {
-        background-color: rgba(250, 0, 0, 0.1);
+      :host {
+        --card-bg: rgba(250, 0, 0, 0.1);
       }
     `,
   ],
-  imports: [CardComponent],
+  imports: [CardComponent, NgOptimizedImage, ListItemComponent],
 })
 export class TeacherCardComponent implements OnInit {
+  private readonly teacherStore = inject(TeacherStore);
+
   private http = inject(FakeHttpService);
   private store = inject(TeacherStore);
 
@@ -31,4 +55,12 @@ export class TeacherCardComponent implements OnInit {
   ngOnInit(): void {
     this.http.fetchTeachers$.subscribe((t) => this.store.addAll(t));
   }
+
+  addNew(): void {
+    this.teacherStore.addOne(randTeacher());
+  }
+
+  deleteSingle(id: number): void {
+    this.teacherStore.deleteOne(id);
+  }
 }

apps/angular/1-projection/src/app/data-access/city.store.ts

@@ -5,7 +5,7 @@ import { City } from '../model/city.model';
   providedIn: 'root',
 })
 export class CityStore {
-  private cities = signal<City[]>([]);
+  public readonly cities = signal<City[]>([]);
 
   addAll(cities: City[]) {
     this.cities.set(cities);

apps/angular/1-projection/src/app/ui/card/card.component.ts

@@ -1,58 +1,33 @@
-import { NgOptimizedImage } from '@angular/common';
-import { Component, inject, input } from '@angular/core';
-import { randStudent, randTeacher } from '../../data-access/fake-http.service';
-import { StudentStore } from '../../data-access/student.store';
-import { TeacherStore } from '../../data-access/teacher.store';
-import { CardType } from '../../model/card.model';
-import { ListItemComponent } from '../list-item/list-item.component';
+import { NgTemplateOutlet } from '@angular/common';
+import { Component, ContentChild, input, TemplateRef } from '@angular/core';
 
 @Component({
   selector: 'app-card',
   template: `
     <div
       class="flex w-fit flex-col gap-3 rounded-md border-2 border-black p-4"
+      style="background-color: var(--card-bg, transparent)"
       [class]="customClass()">
-      @if (type() === CardType.TEACHER) {
-        <img ngSrc="assets/img/teacher.png" width="200" height="200" alt="" />
-      }
-      @if (type() === CardType.STUDENT) {
-        <img ngSrc="assets/img/student.webp" width="200" height="200" alt="" />
-      }
+      <ng-content select="[card-header]"></ng-content>
 
       <section>
         @for (item of list(); track item) {
-          <app-list-item
-            [name]="item.firstName"
-            [id]="item.id"
-            [type]="type()"></app-list-item>
+          <ng-container
+            *ngTemplateOutlet="
+              itemTemplate;
+              context: { $implicit: item }
+            "></ng-container>
         }
       </section>
 
-      <button
-        class="rounded-sm border border-blue-500 bg-blue-300 p-2"
-        (click)="addNewItem()">
-        Add
-      </button>
+      <ng-content select="[card-action]"></ng-content>
     </div>
   `,
-  imports: [ListItemComponent, NgOptimizedImage],
+  imports: [NgTemplateOutlet],
 })
 export class CardComponent {
-  private teacherStore = inject(TeacherStore);
-  private studentStore = inject(StudentStore);
-
   readonly list = input<any[] | null>(null);
-  readonly type = input.required<CardType>();
   readonly customClass = input('');
 
-  CardType = CardType;
-
-  addNewItem() {
-    const type = this.type();
-    if (type === CardType.TEACHER) {
-      this.teacherStore.addOne(randTeacher());
-    } else if (type === CardType.STUDENT) {
-      this.studentStore.addOne(randStudent());
-    }
-  }
+  @ContentChild('itemTemplate') itemTemplate!: TemplateRef<any>;
 }

apps/angular/1-projection/src/app/ui/list-item/list-item.component.ts

@@ -1,39 +1,26 @@
 import {
   ChangeDetectionStrategy,
   Component,
-  inject,
   input,
+  output,
 } from '@angular/core';
-import { StudentStore } from '../../data-access/student.store';
-import { TeacherStore } from '../../data-access/teacher.store';
 import { CardType } from '../../model/card.model';
 
 @Component({
   selector: 'app-list-item',
   template: `
     <div class="flex justify-between border border-gray-300 px-2 py-1">
       {{ name() }}
-      <button (click)="delete(id())">
+      <button (click)="emitDelete.emit(id())">
         <img class="h-5" src="assets/svg/trash.svg" alt="trash" />
       </button>
     </div>
   `,
   changeDetection: ChangeDetectionStrategy.OnPush,
 })
 export class ListItemComponent {
-  private teacherStore = inject(TeacherStore);
-  private studentStore = inject(StudentStore);
-
   readonly id = input.required<number>();
   readonly name = input.required<string>();
   readonly type = input.required<CardType>();
-
-  delete(id: number) {
-    const type = this.type();
-    if (type === CardType.TEACHER) {
-      this.teacherStore.deleteOne(id);
-    } else if (type === CardType.STUDENT) {
-      this.studentStore.deleteOne(id);
-    }
-  }
+  readonly emitDelete = output<number>();
 }