App\Models\Forum\Topic::setCover PHP Method

    public function setCover($path, $user)
    {
        if ($this->cover === null) {
            TopicCover::upload($path, $user, $this);
        } else {
            $this->cover->storeFile($path);
            $this->cover->user()->associate($user);
            $this->cover->save();
        }
        return $this->fresh();
    }