OpenCart 🇺🇦

$this->db = $registry->get('db');
$this->config = $registry->get('config');

$length_class_query = $this->db->query("SELECT * FROM " . DB_PREFIX . "length_class mc LEFT JOIN " . DB_PREFIX . "length_class_description mcd ON (mc.length_class_id = mcd.length_class_id) WHERE mcd.language_id = '" . (int)$this->config->get('config_language_id') . "'");

foreach ($length_class_query->rows as $result) {
	$this->lengths[$result['length_class_id']] = array(
		'length_class_id' => $result['length_class_id'],
		'title'           => $result['title'],
		'unit'            => $result['unit'],
		'value'           => $result['value']
	);
}

if ($from == $to) {
	return $value;
}

if (isset($this->lengths[$from])) {
	$from = $this->lengths[$from]['value'];
} else {
	$from = 0;
}

if (isset($this->lengths[$to])) {
	$to = $this->lengths[$to]['value'];
} else {
	$to = 0;
}		

return $value * ($to / $from);

if (isset($this->lengths[$length_class_id])) {
	return number_format($value, 2, $decimal_point, $thousand_point) . $this->lengths[$length_class_id]['unit'];
} else {
	return number_format($value, 2, $decimal_point, $thousand_point);
}

if (isset($this->lengths[$length_class_id])) {
	return $this->lengths[$length_class_id]['unit'];
} else {
	return '';
}