Easy Digital Downloads Currency Switcher - Basic Integration

class SomeClass {
  /**
   * Basic integration with Easy Digital Downloads Currency Switcher, developed by Aelia
   * (http://aelia.co). This method can be used by any 3rd party plugin to
   * return prices converted to the active currency.
   *
   * @param double price The source price.
   * @param string to_currency The target currency. If empty, the active currency
   * will be taken.
   * @param string from_currency The source currency. If empty, Easy Digital Downloads base
   * currency will be taken.
   * @return double The price converted from source to destination currency.
   * @author Aelia <support@aelia.co>
   * @link http://aelia.co
   * @link https://aelia.co/shop/currency-switcher-for-easy-digital-downloads/
   */
  public static function get_price_in_currency($price, $to_currency = null, $from_currency = null) {
    if(empty($from_currency)) {
      global $edd_options;
      $from_currency = $edd_options['currency'];
    }
    if(empty($to_currency)) {
      $to_currency = edd_get_currency();
    }
    return apply_filters('edd_aelia_cs_convert', $price, $from_currency, $to_currency);
  }

  public function test() {
    $price = 123;
    // Just call the get_price_in_currency() method, no further action required
    return self::get_price_in_currency($price);
  }
}