How to pass whereIn through when in laravel?

Question

Laravel

...
            ->when(request('site_id', false), function ($q, $sites) {
                $q->whereIn('site_id', $sites); // не работает
            })
            ->when(request('href', false), function ($q, $search) {
                $q->where('href', 'like', "%$search%");// работает
            }) ...
        if($sites) {
             $query->whereIn('site_id', $sites); // работает
        }

It's just a desire to transform the code a bit and not to cut everything through if, but when in the when construct does not work out. With what can be connected?

Answer 1

Because you need to study PHP first - php.net/manual/en/functions.anonymous.php

Answer 2

Do you have a ruler on your hands to beat for such desires?
the controller decides what to do.
the model provides data.
the view renders.
and you are making a puzzle.