private function checkSeoAttributes()
    {
        $model = $this->owner;
        $transliterationFunction = $this->transliterationFunction;

        // if slug field is empty, filling one with generated slug
        if ($this->slugAttribute && $model->{$this->slugAttribute} == null) {
            $model->{$this->slugAttribute} = $transliterationFunction($model->{$this->nameAttribute});
        }

        // if some seo field is empty, filling it with name field data
        foreach ($this->seoAttributes as $seoAttribute) {
            if ($model->{$seoAttribute} == null){
                $model->{$seoAttribute} = $model->{$this->nameAttribute};
            }
        }
    }