(*
 * Copyright (C) 2003:
 *    Stefano Zacchiroli <zack@cs.unibo.it>
 *    for the HELM Team http://helm.cs.unibo.it/
 *
 *  This file is part of HELM, an Hypertextual, Electronic
 *  Library of Mathematics, developed at the Computer Science
 *  Department, University of Bologna, Italy.
 *
 *  HELM 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.
 *
 *  HELM 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 HELM; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 *  MA  02111-1307, USA.
 *
 *  For details, see the HELM World-Wide-Web page,
 *  http://helm.cs.unibo.it/
 *)

open Hbugs_types;;
open Printf;;

let debug_print = 
  let debug = true in
  fun s -> prerr_endline (sprintf "HBUGS DEBUG: %s" s)
;;

exception NoProofInProgress;;

let hbugs_client = ref None
let use_hint_callback = ref ignore
let describe_hint_callback = ref ignore

let set_describe_hint_callback c = describe_hint_callback := c

let quit () =
  match !hbugs_client with
  | Some c -> c#unregisterFromBroker ()
  | None -> ()

let hbugs_enabled = ref false

let get_hbugs_client () =
  match !hbugs_client with
  | Some c -> c
  | None -> assert false

let disable () =
  match !hbugs_client with None -> () | Some c -> c#hide ()

let notify () =
  try
    if !hbugs_enabled then begin
      let client = get_hbugs_client () in
      let goal =
        match !ProofEngine.goal with
        | Some g -> g
        | None -> raise NoProofInProgress
      in
      let (type_string, body_string) =
        let (type_xml, body_xml) = ProofEngine.get_current_status_as_xml () in
        (Xml.pp_to_string type_xml, Xml.pp_to_string body_xml)
      in
      let new_state =
        (Misc.strip_xml_headings type_string,
         Misc.strip_xml_headings body_string,
         goal)
      in
      client#stateChange (Some new_state)
    end
  with NoProofInProgress -> ()

let clear () =
 if !hbugs_enabled then
  begin
   let client = get_hbugs_client () in
    client#stateChange None
  end

let rec enable () =
  (match !hbugs_client with
  | None -> (* create an hbugs client and show its window *)
      hbugs_client :=
        (try
          Some (new Hbugs_client.hbugsClient
            ~use_hint_callback:!use_hint_callback
            ~describe_hint_callback:!describe_hint_callback
              ())
        with e ->
          prerr_endline (sprintf "Can't start HBugs client: %s"
            (Printexc.to_string e));
          None);
      (match !hbugs_client with
      |Some client ->
          client#show ();
          client#subscribeAll ()
      | None -> ())
  | Some c -> (* show hbugs client window *)
      c#show ())

let toggle state =
  if state <> !hbugs_enabled then begin (* status has been changed *)
    if state then enable () else disable ();
    clear ()
  end;
  hbugs_enabled := state

module type Unit = sig end

module Initialize (Tactics: InvokeTactics.Tactics) : Unit =
  struct
    let use_hint = function
      | Use_ring -> Tactics.ring ()
      | Use_fourier -> Tactics.fourier ()
      | Use_reflexivity -> Tactics.reflexivity ()
      | Use_symmetry -> Tactics.symmetry ()
      | Use_assumption -> Tactics.assumption ()
      | Use_contradiction -> Tactics.contradiction ()
      | Use_exists -> Tactics.exists ()
      | Use_split -> Tactics.split ()
      | Use_left -> Tactics.left ()
      | Use_right -> Tactics.right ()
      | Use_apply term ->
         (* we remove the "cic:" prefix *)
         let term' = String.sub term 4 (String.length term - 4) in
          Tactics.apply ~term:term' ()
      | Hints _ -> assert false

    let _ = use_hint_callback := use_hint
  end

let start_web_services () = ignore (Unix.system "make -C ../hbugs/ start")
let stop_web_services () = ignore (Unix.system "make -C ../hbugs/ stop")