(* COCANWIKI - a wiki written in Objective CAML.
 * Written by Richard W.M. Jones <rich@merjis.com>.
 * Copyright (C) 2004 Merjis Ltd.
 * $Id: largest_pages.ml,v 1.6 2006/03/28 16:24:07 rich Exp $
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *)

open Apache
open Registry
open Cgi
open Printf

open Cocanwiki
open Cocanwiki_template

let limit = 50
let modem_speed = 56000 / 10		(* 56kbps modem. *)
let overhead = 2 (* Number of seconds to open connection + render page. *)

let run r (q : cgi) dbh hostid _ _ =
  let template = get_template dbh hostid "largest_pages.html" in

  (* Grab the pages from the database, ordered by size.
   * NB.  At the moment we count the size of the markup, which is only an
   * approximation of the final size of the page.  Also, we are not taking
   * into account images.
   *)
  let rows =
    PGSQL(dbh)
      "select p.id, p.url, p.title, sum (length (c.content))
         from pages p, contents c
        where p.hostid = $hostid and p.url is not null and p.redirect is null
          and c.pageid = p.id group by 1, 2, 3 order by 4 desc" in

  let table =
    List.map
      (fun (pageid, page, title, size) ->
	   let page = Option.get page in
	   let size = Int64.to_int (Option.get size) in
	   let download_time = overhead + size / modem_speed in (* seconds *)
	   let download_time =
	     if download_time <= 4 then "<= 4 s"
	     else if download_time < 60 then sprintf "%d s" download_time
	     else
	       sprintf "%d m %d s" (download_time / 60) (download_time mod 60)
	   in

	   let size =
	     if size < 4096 then sprintf "%d bytes" size
	     else sprintf "%d K" (size / 1024) in

	   [ "pageid", Template.VarString (Int32.to_string pageid);
	     "page", Template.VarString page;
	     "title", Template.VarString title;
	     "size", Template.VarString size;
	     "download_time", Template.VarString download_time ]
      ) rows in
  template#table "pages" table;

  q#template template

let () =
  register_script ~restrict:[CanView] run