(*
    ||M||  This file is part of HELM, an Hypertextual, Electronic        
    ||A||  Library of Mathematics, developed at the Computer Science     
    ||T||  Department, University of Bologna, Italy.                     
    ||I||                                                                
    ||T||  HELM is free software; you can redistribute it and/or         
    ||A||  modify it under the terms of the GNU General Public License   
    \   /  version 2 or (at your option) any later version.              
     \ /   This software is distributed as is, NO WARRANTY.              
      V_______________________________________________________________ *)

module KF = Filename
module KP = Printf

module U  = NUri
module C  = Cps
module G  = Options
module N  = Layer
module E  = Entity
module R  = Alpha
module B  = Brg

IFDEF MANAGER THEN

(* Internal functions *******************************************************)

let version = KP.sprintf "This file was generated by %s: do not edit" (G.version_string true)

let ok = ref true

let uris = ref []

let chunk = ref 0

let sub_och = ref stdout

let top_age = 7000

let size = 250

let base = "lp"

let ext_lp = ".elpi"

let reserved = ["pi"; "sigma"; "nil"; "delay"; "in"; "with"; "resume"; "context"]

let alpha n =
   if List.mem n reserved then !G.alpha ^ n else n

let out_preamble och =
   let ich = open_in !G.preamble in
   let rec aux () = KP.fprintf och "%s\n" (input_line ich); aux () in
   try aux () with End_of_file -> close_in ich

let out_top_comment och msg =
   KP.fprintf och "%% %s\n\n" msg

let out_comment och msg =
   KP.fprintf och "%% %s\n" msg 

let out_clause och msg =
   KP.fprintf och "%s\n\n" msg 

let out_uri och u =
   let str = U.string_of_uri u in
   let rec aux i =
     let c = str.[i] in
     if c = '.' then () else begin 
        output_char och (if c = '/' then '_' else c);
        aux (succ i)
     end
   in
   let rec strip i n = 
      if n <= 0 then succ i else
      strip (String.index_from str (succ i) '/') (pred n)
   in
   aux (strip 0 3)

let out_name och a =
   let f n = function 
      | true  -> KP.fprintf och "%s" (alpha n)
      | false -> KP.fprintf och "_"
   in
   let err () = f "" false in
   E.name err f a

let rec out_term st e och = function
   | B.Sort k                        ->
      let sort = if k = 0 then "(s+type 0)" else if k = 1 then "(s+prop 0)" else assert false in
      KP.fprintf och "(sort %s)" sort
   | B.LRef (_, i)                   ->
      let _, _, _, y, b = B.get e i in
      KP.fprintf och "%a" out_name y
   | B.GRef (_, s)                   ->
      KP.fprintf och "%a" out_uri s
   | B.Cast (u, t)                   ->
      KP.fprintf och "(abbr %a %a x\\ x)" (out_term st e) t (out_term st e) u 
   | B.Appl (_, v, t)                ->
      KP.fprintf och "(appl %a %a)" (out_term st e) t (out_term st e) v
   | B.Bind (y, B.Abst (r, n, w), t) ->
      let y = R.alpha B.mem e y in
      let ee = B.push e B.empty E.empty_node y (B.abst r n w) in
      let c = match r, N.to_string st n with
         | false, "1" -> "prod"
         | false, "2" -> "abst"
         | _          -> ok := false; "?"
      in
      KP.fprintf och "(%s %a %a\\ %a)"
         c (out_term st e) w out_name y (out_term st ee) t
   | B.Bind (_, B.Void, _)           -> C.err ()
   | B.Bind (_, B.Abbr _, _)         -> C.err ()

(* PTS variant 2 ************************************************************)

let output_entity_pts2 och st (_, na, u, b) =
   if na.E.n_apix < !G.first then begin
   match b with
      | E.Abbr (_, B.Cast (w, v)) ->
         KP.fprintf och "get_expansion %a %u %a.\n"
            out_uri u na.E.n_apix (out_term st B.empty) v;
         KP.fprintf och "get_type %a %a.\n\n"
            out_uri u (out_term st B.empty) w; !ok
      | E.Abst (_, w)             ->
         KP.fprintf och "get_type %a %a.\n\n"
            out_uri u (out_term st B.empty) w; !ok
      | _                         -> C.err ()
   end else if na.E.n_apix <= !G.last then begin
   match b with
      | E.Abbr (_, B.Cast (w, v)) ->
         KP.fprintf och "g+line+2 %a %u\n         %a\n         %a\n.\n\n"
            out_uri u na.E.n_apix (out_term st B.empty) v (out_term st B.empty) w;
         uris := (true, u) :: !uris; !ok
      | E.Abst (_, w)             ->
         KP.fprintf och "g+line+1 %a %u\n         %a\n.\n\n"
            out_uri u na.E.n_apix (out_term st B.empty) w;
         uris := (false, u) :: !uris; !ok
      | _                         -> C.err ()
   end else !ok

let close_out_pts2 och () =
   let aux_name (b, s) =
      let gde = if b then "gdef" else "gdec" in 
      KP.fprintf och "(%s %a\n" gde out_uri s
   in
   let aux_sep _ = KP.fprintf och "%s" ")" in
   out_clause och "grundlagen :- is+valid";
   List.iter aux_name (List.rev !uris);
   KP.fprintf och "%s" "gtop";
   List.iter aux_sep !uris;
   out_clause och "\n\n.";
   close_out och

(* Interface functions ******************************************************)

let open_out_pts2 fname =
   let dir = KF.concat !G.manager_dir base in 
   let path = KF.concat dir fname in
   let och = open_out (path ^ "b_pts" ^ ext_lp) in
   out_preamble och;
   out_top_comment och version;
   output_entity_pts2 och, close_out_pts2 och

END