public function update(AttachmentUpdateRequest $request, $id, $manualId)
    {
        $asset = $this->asset->find($id);

        $manual = $this->manual->update($request, $asset->manuals(), $manualId);

        if ($manual) {
            $message = 'Successfully updated manual.';

            return redirect()->route('maintenance.assets.manuals.show', [$asset->id, $manual->id])->withSuccess($message);
        } else {
            $message = 'There was an issue updating this manual. Please try again.';

            return redirect()->route('maintenance.assets.manuals.show', [$id, $manualId])->withErrors($message);
        }
    }