/**
  *
  * Edit existing category
  *
  * @param Request $request
  * @return \Illuminate\Http\JsonResponse|\Illuminate\Http\RedirectResponse
  */
 public function edit(Request $request)
 {
     if ($request->ajax()) {
         $category = Category::find($request->input('id'));
         if (is_null($category)) {
             return response()->json(['msg' => 'Такой категории не существует']);
         }
         return response()->json($category);
     }
     return redirect()->back() - with('msg', $this->no_js);
 }