feat: implement modal service and components for enhanced user interaction, including modal showcase in demo page

src/app/core/services/modal.service.spec.ts

@@ -0,0 +1,133 @@
+import '@angular/compiler';
+import { Component, inject } from '@angular/core';
+import { TestBed, getTestBed } from '@angular/core/testing';
+import {
+  BrowserTestingModule,
+  platformBrowserTesting
+} from '@angular/platform-browser/testing';
+import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from 'vitest';
+
+import {
+  MODAL_DATA,
+  ModalRef,
+  ModalService
+} from './modal.service';
+
+@Component({
+  template: ''
+})
+class FirstTestModalComponent {}
+
+@Component({
+  template: ''
+})
+class SecondTestModalComponent {}
+
+describe('ModalService', () => {
+  let service: ModalService;
+
+  beforeAll(() => {
+    try {
+      getTestBed().initTestEnvironment(
+        BrowserTestingModule,
+        platformBrowserTesting()
+      );
+    } catch {
+      // Test environment may already be initialized by another setup entrypoint.
+    }
+  });
+
+  afterEach(() => {
+    TestBed.resetTestingModule();
+  });
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [ModalService]
+    });
+
+    service = TestBed.inject(ModalService);
+  });
+
+  it('opens a modal and stores the normalized config', () => {
+    const ref = service.open(FirstTestModalComponent, {
+      title: 'Confirmar compra',
+      data: { productId: 10 },
+      size: 'lg',
+      closeOnBackdrop: false
+    });
+
+    const activeModal = service.activeModal();
+
+    expect(activeModal).not.toBeNull();
+    expect(activeModal?.component).toBe(FirstTestModalComponent);
+    expect(activeModal?.ref).toBe(ref);
+    expect(activeModal?.config).toEqual({
+      title: 'Confirmar compra',
+      data: { productId: 10 },
+      size: 'lg',
+      closeOnBackdrop: false,
+      closeOnEscape: true,
+      showCloseButton: true
+    });
+  });
+
+  it('emits the close result and clears the active modal', () => {
+    const ref = service.open(FirstTestModalComponent);
+    const closedSpy = vi.fn();
+
+    ref.afterClosed$.subscribe(closedSpy);
+    ref.close({ confirmed: true });
+
+    expect(closedSpy).toHaveBeenCalledWith({ confirmed: true });
+    expect(service.activeModal()).toBeNull();
+    expect(ref.dismissReason()).toBeNull();
+  });
+
+  it('tracks dismiss reasons when closing programmatically', () => {
+    const ref = service.open(FirstTestModalComponent);
+    const closedSpy = vi.fn();
+
+    ref.afterClosed$.subscribe(closedSpy);
+    ref.dismiss();
+
+    expect(closedSpy).toHaveBeenCalledWith(undefined);
+    expect(ref.dismissReason()).toBe('programmatic');
+    expect(service.activeModal()).toBeNull();
+  });
+
+  it('dismisses the current modal as replaced when another one opens', () => {
+    const firstRef = service.open(FirstTestModalComponent);
+    const firstClosedSpy = vi.fn();
+
+    firstRef.afterClosed$.subscribe(firstClosedSpy);
+
+    const secondRef = service.open(SecondTestModalComponent, {
+      title: 'Segundo modal'
+    });
+
+    expect(firstClosedSpy).toHaveBeenCalledWith(undefined);
+    expect(firstRef.dismissReason()).toBe('replaced');
+    expect(service.activeModal()?.ref).toBe(secondRef);
+    expect(service.activeModal()?.component).toBe(SecondTestModalComponent);
+  });
+
+  it('injects MODAL_DATA and ModalRef into opened components through the host injector contract', () => {
+    const ref = service.open(DataTestModalComponent, {
+      data: { amount: 3 }
+    });
+
+    const activeModal = service.activeModal();
+
+    expect(activeModal?.config.data).toEqual({ amount: 3 });
+    expect(activeModal?.ref).toBe(ref);
+  });
+});
+
+@Component({
+  template: ''
+})
+class DataTestModalComponent {
+  readonly data = inject(MODAL_DATA);
+  readonly modalRef = inject(ModalRef);
+}

src/app/core/services/modal.service.ts

@@ -0,0 +1,147 @@
+import { InjectionToken, Injectable, Type, signal } from '@angular/core';
+import { Observable, Subject } from 'rxjs';
+
+export type ModalSize = 'sm' | 'md' | 'lg' | 'xl' | 'full';
+export type ModalDismissReason =
+  | 'backdrop'
+  | 'escape'
+  | 'programmatic'
+  | 'replaced';
+
+export interface ModalConfig<TData = unknown> {
+  title?: string;
+  data?: TData;
+  size?: ModalSize;
+  closeOnBackdrop?: boolean;
+  closeOnEscape?: boolean;
+  showCloseButton?: boolean;
+}
+
+export interface NormalizedModalConfig<TData = unknown>
+  extends Omit<
+    ModalConfig<TData>,
+    'size' | 'closeOnBackdrop' | 'closeOnEscape' | 'showCloseButton'
+  > {
+  size: ModalSize;
+  closeOnBackdrop: boolean;
+  closeOnEscape: boolean;
+  showCloseButton: boolean;
+}
+
+export interface ActiveModalState<TResult = unknown, TData = unknown> {
+  component: Type<unknown>;
+  config: NormalizedModalConfig<TData>;
+  ref: ModalRef<unknown>;
+}
+
+export const MODAL_DATA = new InjectionToken<unknown>('MODAL_DATA');
+
+const DEFAULT_MODAL_CONFIG: Pick<
+  NormalizedModalConfig,
+  'size' | 'closeOnBackdrop' | 'closeOnEscape' | 'showCloseButton'
+> = {
+  size: 'md',
+  closeOnBackdrop: true,
+  closeOnEscape: true,
+  showCloseButton: true
+};
+
+export class ModalRef<TResult = unknown> {
+  private readonly afterClosedSubject = new Subject<TResult | undefined>();
+  private closed = false;
+
+  readonly afterClosed$: Observable<TResult | undefined> =
+    this.afterClosedSubject.asObservable();
+  readonly dismissReason = signal<ModalDismissReason | null>(null);
+
+  constructor(
+    private readonly closeHandler: (result?: TResult) => void,
+    private readonly dismissHandler: (reason: ModalDismissReason) => void
+  ) {}
+
+  close(result?: TResult): void {
+    if (this.closed) {
+      return;
+    }
+
+    this.closeHandler(result);
+  }
+
+  dismiss(reason: ModalDismissReason = 'programmatic'): void {
+    if (this.closed) {
+      return;
+    }
+
+    this.dismissHandler(reason);
+  }
+
+  finalize(result?: TResult, dismissReason?: ModalDismissReason): void {
+    if (this.closed) {
+      return;
+    }
+
+    this.closed = true;
+    this.dismissReason.set(dismissReason ?? null);
+    this.afterClosedSubject.next(result);
+    this.afterClosedSubject.complete();
+  }
+}
+
+@Injectable({
+  providedIn: 'root'
+})
+export class ModalService {
+  private readonly activeModalState = signal<ActiveModalState | null>(null);
+  readonly activeModal = this.activeModalState.asReadonly();
+
+  open<TComponent, TResult = unknown, TData = unknown>(
+    component: Type<TComponent>,
+    config: ModalConfig<TData> = {}
+  ): ModalRef<TResult> {
+    this.activeModalState()?.ref.dismiss('replaced');
+
+    let ref!: ModalRef<TResult>;
+    ref = new ModalRef<TResult>(
+      (result) => this.close(ref, result),
+      (reason) => this.dismiss(ref, reason)
+    );
+
+    this.activeModalState.set({
+      component,
+      config: this.normalizeConfig(config),
+      ref: ref as ModalRef<unknown>
+    });
+
+    return ref;
+  }
+
+  private close<TResult>(ref: ModalRef<TResult>, result?: TResult): void {
+    if (this.activeModalState()?.ref !== ref) {
+      return;
+    }
+
+    ref.finalize(result);
+    this.activeModalState.set(null);
+  }
+
+  private dismiss<TResult>(
+    ref: ModalRef<TResult>,
+    reason: ModalDismissReason = 'programmatic'
+  ): void {
+    if (this.activeModalState()?.ref !== ref) {
+      return;
+    }
+
+    ref.finalize(undefined, reason);
+    this.activeModalState.set(null);
+  }
+
+  private normalizeConfig<TData>(
+    config: ModalConfig<TData>
+  ): NormalizedModalConfig<TData> {
+    return {
+      ...DEFAULT_MODAL_CONFIG,
+      ...config
+    };
+  }
+}