(* COCANWIKI - a wiki written in Objective CAML.
 * Written by Richard W.M. Jones <rich@merjis.com>.
 * Copyright (C) 2004 Merjis Ltd.
 * $Id: cocanwiki_server_settings.ml,v 1.3 2004/10/09 15:01:58 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

(* Server-wide settings.
 *
 * These are stored in a single row in the database in the table
 * 'server_settings'.  You must restart the server if you change
 * this row.
 *
 * It's not possible to read these at server start-up time because the
 * Apache server is still running as 'root' and will not normally be
 * allowed to access the database.  We thus read them at the earliest
 * opportunity, in a request context, and cache the results.
 *)
let server_settings_version, server_settings_stats_page,
    server_settings_crash_email =
  let default = 1, None, None in
  let settings = ref None in
  let get_settings (dbh : Dbi.connection) =
    let sth = dbh#prepare "select version, stats_page, crash_email
                             from server_settings" in
    sth#execute [];
    let s =
      try
	(match sth#fetch1 () with
	   | [ `Int version; (`String _ | `Null) as stats_page;
	       (`String _ | `Null) as crash_email ] ->
	       let stats_page =
		 match stats_page with `String s -> Some s | `Null -> None in
	       let crash_email =
		 match crash_email with `String s -> Some s | `Null -> None in
	       version, stats_page, crash_email
	   | _ -> assert false)
      with
	  Not_found -> default in
    sth#finish ();
    settings := Some s;
    s
  in

  let server_settings_version dbh =
    let (version, _, _) =
      match !settings with
	  None -> get_settings dbh
	| Some settings -> settings in
    version
  in

  let server_settings_stats_page dbh =
    let (_, stats_page, _) =
      match !settings with
	  None -> get_settings dbh
	| Some settings -> settings in
    stats_page
  in

  let server_settings_crash_email dbh =
    let (_, _, crash_email) =
      match !settings with
	  None -> get_settings dbh
	| Some settings -> settings in
    crash_email
  in

  server_settings_version, server_settings_stats_page,
  server_settings_crash_email