koel/app/Values/SmartPlaylistRuleGroup.php

<?php

namespace App\Values;

use Illuminate\Contracts\Support\Arrayable;
use Illuminate\Support\Arr;
use Illuminate\Support\Collection;

final class SmartPlaylistRuleGroup implements Arrayable
{
    private function __construct(public int $id, public Collection $rules)
    {
    }

    public static function create(array $array): self
    {
        return new self(
            id: Arr::get($array, 'id'),
            rules: collect(Arr::get($array, 'rules', []))->transform([SmartPlaylistRule::class, 'create']),
        );
    }

    /** @return array<mixed> */
    public function toArray(): array
    {
        return [
            'id' => $this->id,
            'rules' => $this->rules->toArray(),
        ];
    }
}