Using functions in Laravel macros

I would like to extend Eloquent Builder to have a support for search function. Inside my service provider I’ve added the following:

Builder::macro('search', function (string $searchBy) {
    ...
}

which works. I can now call a search method on my model.

The issue I’m having is that the logic within it is getting a rather complex and I wouldn’t like it to be a single large script, however splitting to functions doesn’t work since scope when inside a macro callback is actually from Eloquent Builder.

So this doesn’t work:

public function foo()
{
    dd('bar');
}

public function boot()
{
    Builder::macro('search', function (string $searchBy) {
        $this->bla();
        ...
    }
}

Is there a way to use functions without going over the hassle of extending complete Eloquent Builder?

Answer

I have ended up creating a class which would contain the complete logic I need. I see this as a fairly good OOP practice.

Builder::macro('search', function (array $input) {
    $jsonQuery = new JsonQuery($this, $input);
    $jsonQuery->search();

    return $this;
});

For anyone interested in details, you can check out my JSON search package.