(* COCANWIKI - a wiki written in Objective CAML.
 * Written by Richard W.M. Jones <rich@merjis.com>.
 * Copyright (C) 2004 Merjis Ltd.
 * $Id: page_email_send.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_ok
open Cocanwiki_template
open Cocanwiki_strings

let run r (q : cgi) dbh hostid { hostname = hostname } _ =
  let template = get_template dbh hostid "page_email_send.txt" in

  let page = q#param "page" in
  let email = trim (q#param "email") in

  if email = "" then (
    error ~title:"No email address" ~back_button:true
      dbh hostid q "You must give an email address.";
    return ()
  );

  (* Good a place as any to delete old, unconfirmed emails. *)
  PGSQL(dbh)
    "delete from page_emails
      where pending is not null
        and entry_date < current_date - 7";

  PGOCaml.commit dbh;
  PGOCaml.begin_work dbh;

  (* Is that email address already registered in the database? *)
  let rows = PGSQL(dbh)
    "select 1 from page_emails where hostid = $hostid
        and url = $page and email = $email" in

  let registered = rows = [Some 1l] in

  if registered then (
    error ~title:"Email address already used" ~back_button:true
      dbh hostid q
      ("That email address is already used for notifications from this page. "^
       "If you are not receiving updates for this page, then you will " ^
       "need to confirm that address. If you continue to have problems " ^
       "please contact the site administrator.");
    return ()
  );

  (* Create the unique pending and opt_out fields.  The pending field
   * allows the user to register.  The opt_out field allows the user
   * to unsubscribe.
   *)
  let pending = random_sessionid () in
  let opt_out = random_sessionid () in

  (* Insert into the database. *)
  PGSQL(dbh)
    "insert into page_emails (hostid, url, email, pending, opt_out)
     values ($hostid, $page, $email, $pending, $opt_out)";

  PGOCaml.commit dbh;

  (* Send the initial email to the user. *)
  template#set "hostname" hostname;
  template#set "page" page;
  template#set "pending" pending;
  template#set "opt_out" opt_out;

  let body = template#to_string in
  let subject = "Site notice: " ^ hostname ^ ": Confirm your email address" in
  Sendmail.send_mail ~subject ~to_addr:[email] body;

  (* Finish up. *)
  let buttons = [ ok_button ("/" ^ page) ] in
  ok ~buttons ~title:"Confirmation email sent"
    dbh hostid q
    ("Please check your email now.  You have been sent a confirmation " ^
     "email so we can verify the email address is yours.  Click on the " ^
     "first link in that email to confirm.")

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