(* Copyright (C) 2000-2002, HELM Team.
 * 
 * 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://cs.unibo.it/helm/.
 *)

(******************************************************************************)
(*                                                                            *)
(*                               PROJECT HELM                                 *)
(*                                                                            *)
(*                Claudio Sacerdoti Coen <sacerdot@cs.unibo.it>               *)
(*                                 18/02/2003                                 *)
(*                                                                            *)
(*                                                                            *)
(******************************************************************************)

module I = MQueryInterpreter
module U = MQGUtil
module G = MQueryGenerator

  (* search arguments on which Apply tactic doesn't fail *)
let matchConclusion mqi_handle ?(output_html = (fun _ -> ())) ~choose_must () ~status =
 let ((_, metasenv, _, _), metano) = status in
 let (_, ey ,ty) = List.find (function (m,_,_) -> m=metano) metasenv in
  let list_of_must, only = CGMatchConclusion.get_constraints metasenv ey ty in
  let must = choose_must list_of_must only in
  let result =
	 I.execute mqi_handle 
	    (G.query_of_constraints
        (Some U.universe_for_match_conclusion)
        (must,[],[]) (Some only,None,None)) in 
	let uris =
	 List.map
		(function uri,_ ->
			MQueryMisc.wrong_xpointer_format_from_wrong_xpointer_format' uri
		) result in
	 let uris',exc =
		let rec filter_out =
		 function
				[] -> [],""
			| uri::tl ->
				 let tl',exc = filter_out tl in
					try
					 if
						(try
						 ignore
							(PrimitiveTactics.apply_tac
							 ~term:(MQueryMisc.term_of_cic_textual_parser_uri
								(MQueryMisc.cic_textual_parser_uri_of_string uri))
							 ~status);
						 true
						with ProofEngineTypes.Fail _ -> false)
					 then
						uri::tl',exc
					 else
						tl',exc
					with
           (ProofEngineTypes.Fail _) as e ->
						 let exc' =
						  "<h1 color=\"red\"> ^ Exception raised trying to apply " ^
							 uri ^ ": " ^ Printexc.to_string e ^ " </h1>" ^ exc
						 in
						  tl',exc'
		in
		 filter_out uris
	 in
		let html' =
		 " <h1>Objects that can actually be applied: </h1> " ^
		 String.concat "<br>" uris' ^ exc ^
		 " <h1>Number of false matches: " ^
			string_of_int (List.length uris - List.length uris') ^ "</h1>" ^
		 " <h1>Number of good matches: " ^
			string_of_int (List.length uris') ^ "</h1>"
		in
		 output_html html' ;
		 uris'
;;