sfp_api_laravel_ginastica_cerebro/app/Http/Requests/UnitMediaRequest.php

<?php

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class UnitMediaRequest extends FormRequest
{
    public function rules(): array
    {
        $isUpdate = $this->isMethod('PUT') || $this->isMethod('PATCH');

        return [
            'unit_id'               => 'required|integer|exists:units,id',
            'title'                 => 'required|string|max:255',
            'file'                  => ($isUpdate ? 'nullable' : 'required') . '|file|max:51200',
            'visible_to_franchisee' => 'boolean',
        ];
    }
}