Paginação para mostrar o valor máximo e limitar o resto

    <?php
        $link = "";
 // $page = $_GET['page'];
 // $pages=20; // Hardcoded for testing purpose
  $limit=5  ;
    if ($pages >=1 && $page <= $pages)
    {
        $counter = 1;
        $link = "";
        if ($page > ($limit/2))
           { $link .= "<a href=\"?page=1\">1 </a> ... ";}
        for ($x=$page; $x<=$pages;$x++)
        {

            if($counter < $limit)
                $link .= "<a href=\"?page=" .$x."\">".$x." </a>";

            $counter++;
        }
        if ($page < $pages - ($limit/2))
         { $link .= "... " . "<a href=\"?page=" .$pages."\">".$pages." </a>"; }
    }

    echo $link;
?>

//At page=1
1 2 3 4 ... 20 

//At page=12
1 ... 12 13 14 15 ... 20 

//At page=18
1 ... 18 19 20