(* Copyright (C) 2000, 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                                 *)
(*                                                                            *)
(*                     Ferruccio Guidi <fguidi@cs.unibo.it>                   *)
(*                                 30/04/2002                                 *)
(*                                                                            *)
(*                                                                            *)
(******************************************************************************)

(* Query issuing functions **************************************************)



type uri = string
type position = string
type depth = int
type sort = string 

type r_obj = (uri * position * depth option)  
type r_rel = (position* depth) 
type r_sort = (position* depth * sort) 

type must_restrictions = (r_obj list * r_rel list * r_sort list)
type can_restrictions = (r_obj list option * r_rel list option * r_sort list option)









exception Discard  

let nl = " <p>\n"

let query_num = ref 1

let log_file = ref ""

let confirm_query = ref (fun _ -> true)

let info = ref []

let set_log_file f = 
   log_file := f

let set_confirm_query f =
   confirm_query := f

let get_query_info () = ! info

let execute_query query =
   let module Util = MQueryUtil in
   let mode = [Open_wronly; Open_append; Open_creat; Open_text] in
   let perm = 64 * 6 + 8 * 6 + 4 in
   let time () =
      let lt = Unix.localtime (Unix.time ()) in
      "NEW LOG: " ^
      string_of_int (lt.Unix.tm_mon + 1) ^ "-" ^
      string_of_int (lt.Unix.tm_mday + 1) ^ "-" ^
      string_of_int (lt.Unix.tm_year + 1900) ^ " " ^
      string_of_int (lt.Unix.tm_hour) ^ ":" ^
      string_of_int (lt.Unix.tm_min) ^ ":" ^
      string_of_int (lt.Unix.tm_sec) 
   in
   let log q r = 
      let och = open_out_gen mode perm ! log_file in
      if ! query_num = 1 then output_string och (time () ^ nl);
      let str =
       "Query: " ^ string_of_int ! query_num ^ nl ^ Util.text_of_query q ^ nl ^ 
       "Result:" ^ nl ^ Util.text_of_result r nl in
      output_string och str; 
      flush och 
   in
   let execute q =
      let r = Mqint.execute q in    
      if ! log_file <> "" then log q r; 
      info := string_of_int ! query_num :: ! info;
      incr query_num;
      r
   in 
   if ! confirm_query query then execute query else raise Discard
                          
(* Query building functions  ************************************************)   

let locate s =
   let module M = MathQL in
   let q =
    M.Ref (M.Property true M.RefineExact ("objectName", []) (M.Const [s]))
   in
    execute_query q

let searchPattern must_use can_use =    
   let module M = MathQL in
   let in_path s = (s, []) in
   let assign v p = (in_path v, in_path p) in 
   
   let q_where_obj = function
       Some l ->
         M.Sub
         (M.RefOf
           (M.Select
             ("uri", 
               M.Relation
                (false, M.RefineExact, in_path "refObj", 
   	         M.Ref (M.RefOf (M.RVar "uri0")), 
	         [assign "pos" "position"]),
               M.Ex ["uri"]
                (M.Meet (M.VVar "obj_positions", M.Record ("uri", in_path "pos")))
	      )
           ),
           M.VVar "universe"
         )
     | None -> M.True  	 
   in 
    
   let q_where_rel = function
       Some l ->
         M.And
        (M.Sub(M.VVar "rel_positions", M.Property(false, M.RefineExact, ("refRel", ["position"]), M.RefOf(M.RVar "uri0"))),
         M.Sub(M.VVar "rel_depths", M.Property(false, M.RefineExact, ("refRel", ["depth"]), M.RefOf(M.RVar "uri0"))))
     | None -> M.True
   in 

   let q_where_sort = function
       Some l ->
         M.And
	(M.And
        (M.Sub(M.VVar "sort_positions", M.Property(false, M.RefineExact, ("refSort", ["position"]), M.RefOf(M.RVar "uri0"))),
         M.Sub(M.VVar "sort_depths", M.Property(false, M.RefineExact, ("refSort", ["depth"]), M.RefOf(M.RVar "uri0")))),
	 M.Sub(M.VVar "sorts", M.Property(false, M.RefineExact, ("refSort", ["sort"]), M.RefOf(M.RVar "uri0"))))
     | None -> M.True
   in
   
   let q_where cr =
     let (cr_o,cr_r,cr_s) = cr in
     M.And(M.And(q_where_obj cr_o, q_where_rel cr_r), q_where_sort cr_s)     
   
       in
   
   let uri_of_entry (r, p, d) = r in
   
   let build_select_obj (r, pos, dep) =
     match dep with
       None -> M.Select
                 ("uri", 
                  M.Relation (false, M.RefineExact, ("backPointer", []),
	                      M.Ref (M.Const [r]), [assign "pos" "position"]),
                  M.Ex ["uri"] 
                  ((M.Sub (M.Const [pos], M.Record ("uri", in_path "pos")))))
     | Some dep -> let string_dep = string_of_int dep in
                   M.Select
                     ("uri", 
                      M.Relation (false, M.RefineExact, ("backPointer", []),
	                          M.Ref (M.Const [r]), [assign "p" "position";assign "d" "depth"]),
                      M.Ex ["uri"] 
                      (M.And
	              ((M.Sub (M.Const [pos], M.Record ("uri", in_path "p"))),
	              (M.Sub (M.Const [string_dep], M.Record ("uri", in_path "d"))))))	
   in 
  
   let build_select_rel (pos, dep) =       
      M.Select                               
       ("uri", 
        M.Relation (true, M.RefineExact, ("refRel", []), M.Ref (M.Const [""]), [assign "p" "position";assign "d" "depth"]), 
        M.Ex ["uri"] 
        (M.And
	((M.Sub (M.Const [pos], M.Record ("uri", in_path "p"))),
	(M.Sub (M.Const [dep], M.Record ("uri", in_path "d"))))))
   in 

   let build_select_sort (pos, dep, sor) =       
      M.Select                               
       ("uri", 
        M.Relation (true, M.RefineExact, ("refSort", []), M.Ref (M.Const [""]), [assign "p" "position";assign "d" "depth";assign "s" "sort"]), 
        M.Ex ["uri"] 
        (M.And
	((M.And
	((M.Sub (M.Const [pos], M.Record ("uri", in_path "p"))),
	(M.Sub (M.Const [dep], M.Record ("uri", in_path "d"))))),
        (M.Sub (M.Const [sor], M.Record ("uri", in_path "s"))))))
   in 

   let rec build_intersect_obj = function
       []       -> M.Pattern (M.Const ["[.]*"])
     | [hd]     -> build_select_obj hd
     | hd :: tl -> M.Intersect (build_select_obj hd, build_intersect_obj tl)
   in
   
   let rec build_intersect_rel = function
       []       -> M.Ref(M.Const [])                      
     | [hd]     -> build_select_rel hd
     | hd :: tl -> M.Intersect (build_select_rel hd, build_intersect_rel tl)
   in

   let rec build_intersect_sort = function
       []       -> M.Ref(M.Const [])                         
     | [hd]     -> build_select_sort hd
     | hd :: tl -> M.Intersect (build_select_sort hd, build_intersect_sort tl)
   in
   
   let build_intersect must = 
      let tostring_sort (a,b,c) = 
        let b1 = string_of_int b in 
          (a,b1,c)
      in
      let tostring_rel (a,b) = 
        let b1 = string_of_int b in 
          (a,b1)
      in
      
      let (l1,l2,l3) = must in
      match (l1,l2,l3) with 
        l1,[],[] -> build_intersect_obj l1
      |	[],l2,[] -> let lrel = List.map tostring_rel l2 in
                      build_intersect_rel lrel
      | [],[],l3 -> let lsort = List.map tostring_sort l3 in
                      build_intersect_sort lsort
      | l1,l2,[] -> let lrel = List.map tostring_rel l2 in
                      M.Intersect (build_intersect_obj l1, build_intersect_rel lrel)
      | l1,[],l3 -> let lsort = List.map tostring_sort l3 in		      
                      M.Intersect (build_intersect_obj l1, build_intersect_sort lsort)
      | [],l2,l3 -> let lrel = List.map tostring_rel l2 in
                    let lsort = List.map tostring_sort l3 in
		      M.Intersect (build_intersect_rel lrel, build_intersect_sort lsort)
      | _ -> let lrel = List.map tostring_rel l2 in
             let lsort = List.map tostring_sort l3 in			  
              M.Intersect (M.Intersect (build_intersect_obj l1, build_intersect_rel lrel), build_intersect_sort lsort)
   in  
  
   let q_in = build_intersect must_use in
   let q_select = M.Select ("uri0", q_in, q_where can_use) in
   
   let (cr_o,cr_r,cr_s) = can_use in
   
   let universe = 
     match cr_o with
       None -> M.Const []
     | Some cr_o -> M.Const (List.map uri_of_entry cr_o) 
   in
  
   let tfst (a,b,c) = a in
   let tsnd (a,b,c) = b in
   let trd (a,b,c) = c in
   
   let opos =
     match cr_o with
       None -> M.Const []
     | Some cr_o -> M.Const (List.map tsnd cr_o) in
   
   let odep =
     match cr_o with
       None -> M.Const []
     | Some cr_o -> let lofc = List.map trd cr_o in
                    let f l c =
		    match c with
		      None -> l 
		    | Some c -> l@[c]
                    in
		    let lof_dep_int = List.fold_left f [] lofc in
		      M.Const(List.map string_of_int lof_dep_int)
   in
    
   let rpos = 
     match cr_r with
       None -> M.Const []
     | Some cr_r -> M.Const (List.map fst cr_r) in
   
   let rdep = 
     match cr_r with
       None -> M.Const []
     | Some cr_r -> let rdep_int = List.map snd cr_r in
                      M.Const (List.map string_of_int rdep_int) 
   in 
   

   let spos = 
     match cr_s with
       None -> M.Const []
     | Some cr_s -> M.Const (List.map tfst cr_s) in
   
      
   let sdep = 
     match cr_s with
       None -> M.Const []
     | Some cr_s -> let sdep_int = List.map tsnd cr_s in
                      M.Const (List.map string_of_int sdep_int)
   in  
   
   
   let sor = 
     match cr_s with
       None -> M.Const[]
     | Some cr_s -> M.Const (List.map trd cr_s) in 
   
   let q_let_u = M.LetVVar ("universe", universe, q_select) in
   
   let q_let_s = M.LetVVar ("sorts", sor, q_let_u) in
   
   let q_let_ds = M.LetVVar ("sort_depths", sdep, q_let_s) in
   
   let q_let_dr = M.LetVVar ("rel_depths", rdep, q_let_ds) in

   let q_let_do = M.LetVVar ("obj_depths", odep, q_let_dr) in  
   
   let q_let_ps = M.LetVVar ("sort_positions", spos, q_let_do) in
   
   let q_let_pr = M.LetVVar ("rel_positions", rpos, q_let_ps) in

   let q_let_po = M.LetVVar ("obj_positions", opos, q_let_pr) in
print_endline ("### " ^ MQueryUtil.text_of_query q_let_po) ; flush stdout;
   execute_query q_let_po