(* COCANWIKI - a wiki written in Objective CAML.
 * Written by Richard W.M. Jones <rich@merjis.com>.
 * Copyright (C) 2004 Merjis Ltd.
 * $Id: restore.ml,v 1.26 2006/08/17 09:11:31 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_ok
open Cocanwiki_diff
open Cocanwiki_emailnotify

let run r (q : cgi) dbh hostid {hostname = hostname} user =
  let version = Int32.of_string (q#param "version") in
  let page = q#param "page" in

  if not (q#param_true "no") then (
    (* Get the IP address of the user, if available. *)
    let logged_ip =
      try Some (Connection.remote_ip (Request.connection r))
      with Not_found -> None in

    let logged_user =
      match user with
	| User (id, _, _, _) -> Some id
	| _ -> None in

    (* Copy the old version of the page to be live. *)
    let rows = PGSQL(dbh)
      "select title, description, keywords, noodp, creation_date,
              redirect, css
         from pages
        where hostid = $hostid
          and url_deleted = $page and id = $version" in

    let title, description, keywords, noodp, creation_date, redirect, css =
      match rows with
      | [row] -> row
      | _ -> assert false in

    PGSQL(dbh)
      "set constraints pages_redirect_cn, sitemenu_url_cn,
           page_emails_url_cn, links_from_cn, recently_visited_url_cn
       deferred";
    PGSQL(dbh) "update pages set url_deleted = url, url = null
                 where hostid = $hostid and url = $page";
    PGSQL(dbh) "insert into pages (hostid, url, title,
                                   description, keywords, noodp,
                                   creation_date, logged_ip,
                                   logged_user, redirect, css)
                values ($hostid, $page, $title, $description, $?keywords,
                        $?noodp,
                        $creation_date,
                        $?logged_ip, $?logged_user, $?redirect, $?css)";

    let pageid = PGOCaml.serial4 dbh "pages_id_seq" in

    PGSQL(dbh) "insert into contents (pageid, ordering,
                                      sectionname, content, divname, divclass,
                                      jsgo)
                select $pageid, ordering, sectionname, content,
                       divname, divclass, jsgo
                  from contents
                 where pageid = $version";

    (* Keep the links table in synch. *)
    Cocanwiki_links.update_links_for_page r dbh hostid page;

    PGOCaml.commit dbh;

    (* Email notify. *)
    let subject = "Page " ^ page ^ " has been restored." in
    let body = fun () ->
      (* Prepare the diff between this version and the previous version. *)
      let diff, _ = get_diff dbh hostid page ~version:pageid () in
      "Page: http://" ^ hostname ^ "/" ^ page ^ "\n\n" ^
      diff in

    email_notify ~body ~subject ~user dbh hostid;

    (* Done. *)
    let buttons = [ ok_button ("/" ^ page) ] in
    ok ~title:"Restored" ~buttons
      dbh hostid q "The old page was restored successfully."
  ) else
    q#redirect ("http://" ^ hostname ^ "/" ^ page)

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