(***********************************************************************)
(*                                                                     *)
(*                               TAToo                                 *)
(*                                                                     *)
(*                     Kim Nguyen, LRI UMR8623                         *)
(*                   Université Paris-Sud & CNRS                       *)
(*                                                                     *)
(*  Copyright 2010-2013 Université Paris-Sud and Centre National de la *)
(*  Recherche Scientifique. All rights reserved.  This file is         *)
(*  distributed under the terms of the GNU Lesser General Public       *)
(*  License, with the special exception on linking described in file   *)
(*  ../LICENSE.                                                        *)
(*                                                                     *)
(***********************************************************************)

(*
  Time-stamp: <Last modified on 2013-02-06 14:24:24 CET by Kim Nguyen>
*)

open Format
type move = [ `Left | `Right | `Up1 | `Up2 | `Epsilon ]
type state_ctx = { left : StateSet.t;
                   right : StateSet.t;
                   up1 : StateSet.t;
                   up2 : StateSet.t;
                   epsilon : StateSet.t}
type ctx_ = { mutable positive : state_ctx;
             mutable negative : state_ctx }
type pred_ = move * bool * State.t

module Move : (Formula.PREDICATE with type data = pred_ and type ctx = ctx_ ) =
struct

  module Node =
  struct
    type t = move * bool * State.t
    let equal n1 n2 = n1 = n2
    let hash n = Hashtbl.hash n
  end

  type ctx = ctx_
  let make_ctx a b c d e =
    { left = a; right = b; up1 = c; up2 = d; epsilon = e }

  include Hcons.Make(Node)

  let print ppf a =
    let _ = flush_str_formatter() in
    let fmt = str_formatter in

    let m, b, s = a.node in
    let dir,num =
      match  m with
      | `Left ->  Pretty.down_arrow, Pretty.subscript 1
      | `Right -> Pretty.down_arrow, Pretty.subscript 2
      | `Epsilon -> Pretty.epsilon, ""
      | `Up1 -> Pretty.up_arrow, Pretty.subscript 1
      | `Up2 -> Pretty.up_arrow, Pretty.subscript 2
    in
    fprintf fmt "%s%s" dir num;
    State.print fmt s;
    let str = flush_str_formatter() in
    if b then fprintf ppf "%s" str
    else Pretty.pp_overline ppf str

  let neg p =
    let l, b, s = p.node in
    make (l, not b, s)

  let eval ctx p =
    let l, b, s = p.node in
    let nctx = if b then ctx.positive else ctx.negative in
    StateSet.mem s begin
      match l with
        `Left -> nctx.left
      | `Right -> nctx.right
      | `Up1 -> nctx.up1
      | `Up2 -> nctx.up2
      | `Epsilon -> nctx.epsilon
    end
end

module SFormula = Formula.Make(Move)
type t = {
  id : Uid.t;
  mutable states : StateSet.t;
  mutable top_states : StateSet.t;
  mutable bottom_states: StateSet.t;
  mutable selection_states: StateSet.t;
  transitions: (State.t, (QNameSet.t*SFormula.t) list) Hashtbl.t;
}



let next = Uid.make_maker ()

let create () = { id = next ();
                  states = StateSet.empty;
                  top_states = StateSet.empty;
                  bottom_states = StateSet.empty;
                  selection_states = StateSet.empty;
                  transitions = Hashtbl.create 17;
 }

let add_trans a q s f =
  let trs = try Hashtbl.find a.transitions q with Not_found -> [] in
  let rem, ntrs =
    List.fold_left (fun (rem, atrs) ((labs, phi) as tr) ->
      let nlabs = QNameSet.inter labs rem in
      if QNameSet.is_empty nlabs then
        (rem, tr :: atrs)
      else
        let nrem = QNameSet.diff rem labs in
        nrem, (nlabs, SFormula.or_ phi f)::atrs
    ) (s, []) trs
  in
  let ntrs = if QNameSet.is_empty rem then ntrs
    else (rem, f) :: ntrs
  in
  Hashtbl.replace a.transitions q ntrs


let print fmt a =
  fprintf fmt
    "Unique ID: %i@\n\
     States %a@\n\
     Top states: %a@\n\
     Bottom states: %a@\n\
     Selection states: %a@\n\
     Alternating transitions:@\n"
    (a.id :> int)
    StateSet.print a.states
    StateSet.print a.top_states
    StateSet.print a.bottom_states
    StateSet.print a.selection_states;
  let trs =
    Hashtbl.fold
      (fun q t acc -> List.fold_left (fun acc (s , f) -> (q,s,f)::acc) acc t)
      a.transitions
      []
  in
  let sorted_trs = List.stable_sort (fun (q1, s1, phi1) (q2, s2, phi2) ->
    let c = State.compare q1 q2 in - (if c == 0 then QNameSet.compare s1 s2 else c))
    trs
  in
  let sfmt = str_formatter in
  let _ = flush_str_formatter () in
  let strs_strings, maxs = List.fold_left (fun (accl, accm) (q, s, f) ->
    let s1 = State.print sfmt q; flush_str_formatter () in
    let s2 = QNameSet.print sfmt s; flush_str_formatter () in
    let s3 = SFormula.print sfmt f; flush_str_formatter () in
    ( (s1, s2, s3) :: accl,
      max
        accm (2 + String.length s1 + String.length s2))
  ) ([], 0) sorted_trs
  in
  List.iter (fun (s1, s2, s3) ->
    fprintf fmt "%s, %s" s1 s2;
    fprintf fmt "%s" (Pretty.padding (maxs - String.length s1 - String.length s2 - 2));
    fprintf fmt "%s  %s@\n" Pretty.right_arrow s3) strs_strings