/** * @param int $page * @param int $end * @param bool $allRecords */ public static function calculate($page, $end = 20, $allRecords = false) { self::$page = intval($page); self::$countPage = ceil($allRecords / $end); self::$end = $end; self::$allRecords = $allRecords; if (self::$page <= 1 or self::$page > self::$countPage) { self::$page = 1; self::$start = 0; } else { self::$start = (self::$page - 1) * self::$end; } }