ldc-supportweb/app/Http/Requests/Bo/AssignTicketToUserRequest.php

<?php

namespace App\Http\Requests\Bo;

use App\Models\User;
use Illuminate\Foundation\Http\FormRequest;

class AssignTicketToUserRequest extends FormRequest
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return boolean
     */
    public function authorize()
    {
        /** @var \App\Models\User */
        $user = auth()->user();
        return auth()->check() and $user->isAdmin();
    }

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        return [
            'assign' => [
                'nullable', 'exists:users,id',
                // phpcs:ignore Generic.CodeAnalysis.UnusedFunctionParameter.FoundBeforeLastUsed
                function ($attribute, $value, $fail) {
                    /** @var \App\Models\User $user */
                    if ($user = User::whereId($value)->first() and !$user->isAdmin()) {
                        $fail(trans('Cet utilisateur ne peut se voir assigner un ticket'));
                    }
                }
            ]
        ];
    }
}