public function rules(): array 	{ 		return [ 			'delivery_country' => ['nullable', 'string', 'size:2', 'exists:' . DeliveryPrice::class . ',country_code'], 			'delivery_zip_code' => ['nullable', 'string', 'max:20'], 			'lang' => ['required', 'string', Rule::in(config('custom.supported_languages'))], 			'items' => ['required', 'array', 'min:1', new ValidateOrderItems(false)], 			'items.*.id' => ['required', 'uuid', 'distinct'], 			'items.*.quantity' => ['required', 'integer', 'min:1'], 			'items.*.type' => ['required', 'string'], 		]; 	}