vehicle interface and vehicle services with comments

.gitignore

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+/node_modules/

src/app/core/interfaces/vehicle.interface.ts

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+export interface VehicleMedia {
+  name: string;
+  url: string;
+}
+
+export interface VehicleEmissions {
+  template: string;
+  value: number;
+}
+
+export interface VehicleMeta {
+  passengers: number;
+  drivetrain: string[];
+  bodystyles: string[];
+  emissions: VehicleEmissions;
+}
+
+/** Shape returned by GET /api/vehicles/ */
+export interface VehicleSummary {
+  id: string;
+  name: string;
+  modelYear: string;
+  apiUrl: string;
+  media: VehicleMedia[];
+}
+
+/** Shape returned by GET /api/vehicles/:id */
+export interface VehicleDetail {
+  id: string;
+  description: string;
+  price: string;
+  meta: VehicleMeta;
+}
+
+/** Merged type used throughout the application */
+export interface Vehicle extends VehicleSummary, VehicleDetail {}
+
+/**
+ * Discriminated union — extend with Motorbike when the API supports it.
+ * e.g. type AnyVehicle = Car | Motorbike;
+ */
+export type AnyVehicle = Vehicle;

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

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+import { HttpClient } from '@angular/common/http';
+import { Injectable, signal } from '@angular/core';
+import {
+  EMPTY,
+  Observable,
+  catchError,
+  forkJoin,
+  map,
+  switchMap,
+} from 'rxjs';
+import {
+  AnyVehicle,
+  VehicleDetail,
+  VehicleSummary,
+} from '../interfaces/vehicle.interface';
+
+const API_BASE =
+  'https://frontend-code-test-api-1023992580432.europe-west2.run.app';
+
+@Injectable({ providedIn: 'root' })
+export class VehicleService {
+  readonly loading = signal(false);
+  readonly error = signal<string | null>(null);
+
+  constructor(private readonly http: HttpClient) {}
+
+  /**
+   * Fetches the vehicle list then retrieves all detail records in parallel.
+   * Uses switchMap so any re-trigger cancels the previous in-flight request,
+   * and forkJoin because HTTP calls are one-shot (complete after one emission).
+   */
+  fetchAll(): Observable<AnyVehicle[]> {
+    this.loading.set(true);
+    this.error.set(null);
+
+    return this.http.get<VehicleSummary[]>(`${API_BASE}/api/vehicles/`).pipe(
+      switchMap((summaries) =>
+        forkJoin(
+          summaries.map((summary) =>
+            this.http
+              .get<VehicleDetail>(`${API_BASE}${summary.apiUrl}`)
+              .pipe(
+                map((detail) => this.merge(summary, detail)),
+                // Per-vehicle errors are swallowed so one bad record
+                // (e.g. "problematic") doesn't kill the entire list.
+                catchError(() => EMPTY),
+              ),
+          ),
+        ),
+      ),
+      map((vehicles) => {
+        this.loading.set(false);
+        return vehicles;
+      }),
+      catchError((err: Error) => {
+        this.loading.set(false);
+        this.error.set(err.message ?? 'Failed to load vehicles');
+        return EMPTY;
+      }),
+    );
+  }
+
+  private merge(summary: VehicleSummary, detail: VehicleDetail): AnyVehicle {
+    return { ...summary, ...detail };
+  }
+}