verted date.
     */
    public function gregorian($date, $format = null)
    {
        $date = $this->normalize_date($date);

        if ($format == null) {
            $format = 'Y m d H:i:s';
        }

        $date = new WPSH_Jalali($date, $this->timezone());
        $date = $date->tog()
      ->format($format);

        return $date;
    }

    /**
     * Latin numbers to Farsi
     *
     * Before showing dates converts its latin numbers to farsi.
     *
     * @deprecated 2.0.0
     *
     * @param int $content Number to convert.
     * @return int Converted number.
     */
    private function persian_num($content) // Display dates in persian numbers evein if jQuery is not available or dates displayed in admin area
    {
        if (!$this->option('persian-num', true, true)) {
            return $content;
        }
        $fa = array(
      '۰',
      '۱',
      '۲',
      '۳',
      '۴',
      '۵',
      '۶',
      '۷',
      '۸',
      '۹'
    );

        $en = array(
      '0',
      '1',
      '2',
      '3',
      '4',
      '5',
      '6',
      '7',
      '8',
      '9'
    );

        $result = str_replace($en, $fa, $content);

        return $result;
    }

    /**
     * Validate pro
     *
     * Pro version validation.
     *
     * @since 3.0.0
     *
     * @return bool true if is validated.
     */
    protected function pro($soft = false)
    {
      $shamsi = WPSH_PLUGINS_PATH . '/wp-shamsi-pro/wp-shamsi-pro.php';
      $exists = file_exists($shamsi) ? true : false;

      if (in_array('wp-shamsi-pro/wp-shamsi-pro.php', apply_filters('active_plugins', get_option('active_plugins'))) && $exists) {
          return true;
        } else {
            return false;
        }

      // @deprecated 4.3.0
      /*
        $serial = !empty(get_option('wpsh_pro_license')) ? get_option('wpsh_pro_license') : false;
        $status = !empty(get_option('wpsh_pro_license_status')) && get_option('wpsh_pro_license_status') == 1 ? true : false;
        $due = !empty(get_option('wpsh_pro_license_due')) && get_option('wpsh_pro_license_due') > current_time('timestamp', false) ? true : false;

        if ($soft) {
          if ($serial && $status && $due) {
            return true;
          } else {
            return false;
          }
        } else {
          if (!in_array('wp-shamsi-pro/wp-shamsi-pro.php', apply_filters('active_plugins', get_option('active_plugins')))) {
            return false;
          }
          if ($serial && $status && $due && $exists) {
            return true;
          } else {
            return false;
          }
        }
      */
    }

    /**
     * Validate VIP
     *
     * VIP version validation.
     *
     * @since 3.0.0
     *
     * @return bool true if is validated.
     */
    protected function vip()
    {
        if (!$this->pro()) {
            return false;
        } else {
            return true; // Since 4.3.0
        }

        $vip = get_option('wpsh_pro_is_vip');

        if (!empty($vip) && $vip == 1) {
            return true;
        }

        return false;
    }

    /**
     * Validate due
     *
     * Pro version due date.
     *
     * @since 3.0.0
     *
     * @return mixed Return in dayas or bool.
     */
    protected function pro_due($int = false)
    {
        if (!$this->pro()) {
            return null;
        }

        $reminder = 30;

        $due = get_option('wpsh_pro_license_due');
        $days = 60 * 60 * 24;
        $now = current_time('timestamp', false);
        $remain = floor(($due - $now) / $days);

        if ($int) {
            return $remain;
        } else {
            if ($remain < $reminder) {
                return true;
            } else {
                return false;
            }
        }
    }

    /**
     * $_GET Mask
     *
     * Mask and escape $_GET
     *
     * @since 2.1.0
     *
     * @param string $key Key of $_GET.
     * @param string $mode String or boolean.
     * @return mixed Escaped result or boolean.
     */
    protected function get($key, $mode = 'string')
    {
        if ($mode == 'string') {
            $get = (isset($_GET[$key])) ? wp_kses_post($_GET[$key]) : null;
        }

        if ($mode == 'bool') {
            $get = (isset($_GET[$key])) ? true : false;
        }

        return $get;
    }

    /**
     * $_POST Mask
     *
     * Mask and escape $_POST
     *
     * @since 2.1.0
     *
     * @param string $key Key of $_POST.
     * @param string $mode String or boolean.
     * @return mixed Escaped result or boolean.
     */
    protected function post($key, $mode = 'string')
    {
        if ($mode == 'string') {
            $post = (isset($_POST[$key])) ? wp_kses_post($_POST[$key]) : null;
        }

        if ($mode == 'bool') {
            $post = (isset($_POST[$key])) ? true : false;
        }

        return $post;
    }
}
<br />
<b>Fatal error</b>:  Uncaught Error: Class 'WPSH_Core' not found in /home/arasetne/public_html/wp-content/plugins/wp-shamsi/inc/autoload.php:20
Stack trace:
#0 /home/arasetne/public_html/wp-content/plugins/wp-shamsi/wp-shamsi.php(28): require_once()
#1 /home/arasetne/public_html/wp-settings.php(517): include_once('/home/arasetne/...')
#2 /home/arasetne/public_html/wp-config.php(188): require_once('/home/arasetne/...')
#3 /home/arasetne/public_html/wp-load.php(50): require_once('/home/arasetne/...')
#4 /home/arasetne/public_html/wp-blog-header.php(13): require_once('/home/arasetne/...')
#5 /home/arasetne/public_html/index.php(17): require('/home/arasetne/...')
#6 {main}
  thrown in <b>/home/arasetne/public_html/wp-content/plugins/wp-shamsi/inc/autoload.php</b> on line <b>20</b><br />