protected function apply_filters(array $data) {

		if(empty($this->filters)) return $data;

		foreach($this->filters as $field => $filters) {

			if(!isset($data[$field])) continue;

			$value = $data[$field];

			foreach($filters as $filter) {
				$value = call_user_func($filter, $value);
			}

			$data[$field] = $value;

		}

		return $data;

	}