feat: add directive for handling images in form

src/app/directives/image-handler.spec.ts

@@ -0,0 +1,36 @@
+import { Component } from '@angular/core';
+import { ImageHandler } from './image-handler';
+import { ComponentFixture, TestBed } from '@angular/core/testing';
+import { FormControl, FormGroup, ReactiveFormsModule } from '@angular/forms';
+
+@Component({
+  selector: 'app-image-handler-mock',
+  imports: [ImageHandler, ReactiveFormsModule],
+  template: `
+  <form [formGroup]="form">
+    <div appImageHandler [imageControl]="form.controls.image"></div>
+  </form>
+  `,
+  styles: [],
+})
+class ImageHandlerTestBed {
+  form = new FormGroup({ image: new FormControl(null) });
+}
+
+describe('ImageHandler', () => {
+  let component: ImageHandlerTestBed;
+  let fixture: ComponentFixture<ImageHandlerTestBed>;
+
+  beforeEach(async () => {
+    TestBed.configureTestingModule({
+      imports: [ImageHandlerTestBed],
+    }).compileComponents();
+    fixture = TestBed.createComponent(ImageHandlerTestBed);
+    component = fixture.componentInstance;
+    await fixture.whenStable();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/directives/image-handler.ts

@@ -0,0 +1,25 @@
+import { ChangeDetectorRef, Directive, HostListener, inject, input, OnInit } from '@angular/core';
+import { FormControl } from '@angular/forms';
+import { take } from 'rxjs';
+//TODO: maybe this could be somehow integrated into the file input using ControlValueAccesor
+
+@Directive({
+  selector: '[appImageHandler]',
+})
+export class ImageHandler implements OnInit {
+  @HostListener('file', ['$event' as any]) updateFileImage(file: File | null) {
+    const control = this.imageControl();
+    control.patchValue(file);
+    control.markAsDirty();
+  }
+  imageControl = input<FormControl<File | null>>(new FormControl(null));
+  private readonly cd = inject(ChangeDetectorRef);
+
+  ngOnInit() {
+    this.imageControl()
+      .valueChanges.pipe(take(1))
+      .subscribe({
+        next: () => this.cd.markForCheck(),
+      });
+  }
+}