feat: implement product and variant CRUD management service with attachment handling

app/Domains/Catalog/Controllers/ProductController.php

@@ -3,6 +3,7 @@
 namespace App\Domains\Catalog\Controllers;
 
 use App\Domains\Catalog\Models\Product;
+use App\Domains\Catalog\Requests\ProductDetailRequest;
 use App\Domains\Catalog\Requests\StoreProductRequest;
 use App\Domains\Catalog\Requests\UpdateProductRequest;
 use App\Domains\Catalog\Resources\ProductResource;
@@ -30,11 +31,11 @@ class ProductController extends Controller
         return ProductResource::make($product)->response()->setStatusCode(201);
     }
 
-    public function show(Request $request, Tenant $tenant, Product $producto, ProductService $productService): ProductResource
+    public function show(ProductDetailRequest $request, Tenant $tenant, Product $producto, ProductService $productService): ProductResource
     {
         $producto = $this->resolveScopedProduct($tenant, $producto);
         $variantId = $request->query('variant_id');
-        $variantId = is_numeric($variantId) ? (int) $variantId : null;
+        $variantId = $variantId !== null ? (int) $variantId : null;
         $producto = $productService->getProductDetail($tenant, $producto, $variantId);
 
         return ProductResource::make($producto);

app/Domains/Catalog/Requests/ProductDetailRequest.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Domains\Catalog\Requests;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class ProductDetailRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function rules(): array
+    {
+        return [
+            'variant_id' => ['sometimes', 'integer'],
+        ];
+    }
+}

app/Domains/Catalog/Services/ProductService.php

@@ -10,6 +10,7 @@ use App\Domains\Tenant\Models\Tenant;
 use Illuminate\Contracts\Pagination\LengthAwarePaginator;
 use Illuminate\Http\UploadedFile;
 use Illuminate\Support\Facades\DB;
+use Illuminate\Validation\ValidationException;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 
 class ProductService
@@ -332,6 +333,12 @@ class ProductService
             throw new NotFoundHttpException('Product variant not found for product.');
         }
 
+        if ($variantId !== null && $selectedVariant->stock <= 0) {
+            throw ValidationException::withMessages([
+                'variant_id' => 'La variante seleccionada no tiene stock.',
+            ]);
+        }
+
         $selectedVariant ??= $product->variants->first();
 
         if ($selectedVariant !== null) {