(* Title:  Specify/i-model.sml

   Author: Walther Neuper 110226

   (c) due to copyright terms

\<open>I_Model\<close> serves students' interactive modelling and gives feedback in the specify-phase.

*)

signature MODEL_FOR_INTERACTION =

sig

  type T

  val empty: T

  type single

  val empty_single: single

  type variant

  type variants

  type m_field

  type descriptor

  datatype feedback = datatype Model_Def.i_model_feedback

  type message

  val feedback_to_string': feedback -> string

  val feedback_to_string: Proof.context -> feedback -> string

  val single_to_string: Proof.context -> single -> string

  val to_string: Proof.context -> T -> string

  datatype add_single = Add of single | Err of string

  val init: Model_Pattern.T -> T

  val check_single: Proof.context -> m_field -> O_Model.T -> T -> Model_Pattern.T ->

    TermC.as_string -> add_single

  val add_single: theory -> single -> T -> T

  val make_tactic: m_field -> TermC.as_string * T -> Tactic.T

  val descriptor: feedback -> descriptor

  val o_model_values: feedback -> O_Model.values

  val variables: T -> term list

  val max_variant: T -> int

  val is_notyet_input : Proof.context -> T -> O_Model.values -> O_Model.single -> Model_Pattern.T

    -> message * single

  val get_field_term: theory -> O_Model.single -> single -> m_field * TermC.as_string

  val environment: T -> Env.T

  val penvval_in: feedback -> term list

  val complete: O_Model.T -> (*Problem*)T -> (*MethodC*)T -> Model_Pattern.T -> T

  val add: single -> T -> T

  val complete_method: O_Model.T * Model_Pattern.T * Model_Pattern.T * T -> T * T

  val is_error: feedback -> bool

  val complete': Model_Pattern.T -> O_Model.single -> single

  val is_complete: T -> bool

  val to_p_model: theory -> feedback -> string

  val eq1: ''a -> 'b * (''a * 'c) -> bool

end

(**)

structure I_Model(**) : MODEL_FOR_INTERACTION(**) =

struct

(**)

(** data types **)

type variant =  Model_Def.variant;

type variants =  Model_Def.variants;

type m_field = Model_Def.m_field;

type descriptor = Model_Def.descriptor;

type T = Model_Def.i_model_single list;

datatype feedback = datatype Model_Def.i_model_feedback;

type single = Model_Def.i_model_single;

val empty_single = Model_Def.i_model_empty;

val empty = []: T;

type message = string;

fun pen2str ctxt (t, ts) =

  pair2str (UnparseC.term ctxt t, (strs2str' o map (UnparseC.term  ctxt)) ts);

fun feedback_to_string ctxt (Cor ((d, ts), penv)) = 

    "Cor " ^ UnparseC.term  ctxt (Input_Descript.join (d, ts)) ^ " ," ^ pen2str ctxt penv

  | feedback_to_string _ (Syn c) = "Syn " ^ c

  | feedback_to_string _ (Typ c) = "Typ " ^ c

  | feedback_to_string ctxt (Inc ((d, ts), penv)) = 

    "Inc " ^ UnparseC.term  ctxt (Input_Descript.join (d, ts)) ^ " ," ^ pen2str ctxt penv

  | feedback_to_string ctxt (Sup (d, ts)) = 

    "Sup " ^ UnparseC.term  ctxt (Input_Descript.join (d, ts))

  | feedback_to_string ctxt (Mis (d, pid)) = 

    "Mis "^ UnparseC.term  ctxt d ^ " " ^ UnparseC.term  ctxt pid

  | feedback_to_string _ (Par s) = "Trm "^s;

fun feedback_to_string' t = feedback_to_string (ThyC.id_to_ctxt "Isac_Knowledge") t;

fun single_to_string ctxt (i, is, b, s, itm_) = 

  "(" ^ string_of_int i ^ " ," ^ ints2str' is ^ " ," ^ bool2str b ^ " ," ^

  s ^ " ," ^ feedback_to_string ctxt itm_ ^ ")";

fun to_string ctxt itms = strs2str' (map (linefeed o (single_to_string ctxt)) itms);

fun make_tactic m_field (term_as_string, i_model) =

  case m_field of

    "#Given" => Tactic.Add_Given' (term_as_string, i_model)

  | "#Find" => Tactic.Add_Find' (term_as_string, i_model)

  | "#Relate" => Tactic.Add_Relation'(term_as_string, i_model)

  | str => raise ERROR ("specify_additem Frm, Pbl: uncovered case with " ^ str);

(** initialise a model **)

fun init pbt = 

  let

    fun pbt2itm (f, (d, _)) = (0, [], false, f, Inc ((d, []), (TermC.empty, [])))

  in map pbt2itm pbt end

(** check input on a model **)

(* find most frequent variant v in itms *)

fun variants itms = ((distinct op =) o flat o (map #2)) (itms: T);

fun cnt itms v = (v, (length o (filter (curry op = v)) o flat o (map #2)) itms);

fun count_variants vts itms = map (cnt itms) vts;

fun max2 [] = raise ERROR "max2 of []"

  | max2 (y :: ys) =

    let

      fun mx (a,x) [] = (a,x)

  	    | mx (a, x) ((b,y) :: ys) = if x < y then mx (b, y) ys else mx (a, x) ys;

    in mx y ys end;

(* get the constant value from a penv *)

fun getval (id, values) = 

  case values of

	  [] => raise ERROR ("penv_value: no values in '" ^ TermC.unparse_ERROR id)

  | [v] => (id, v)

  | (v1 :: v2 :: _) => (case v1 of 

	      Const (\<^const_name>\<open>Program.Arbfix\<close>, _) => (id, v2)

	    | _ => (id, v1));

(* find the variant with most items already input *)

fun max_variant itms = 

    let val vts = (count_variants (variants itms)) itms;

    in if vts = [] then 0 else (fst o max2) vts end;

(* TODO ev. make more efficient by avoiding flat *)

fun mk_e (Cor (_, iv)) = [getval iv]

  | mk_e (Syn _) = []

  | mk_e (Typ _) = [] 

  | mk_e (Inc (_, iv)) = [getval iv]

  | mk_e (Sup _) = []

  | mk_e (Mis _) = []

  | mk_e  _ = raise ERROR "mk_e: uncovered case in fun.def.";

fun mk_en vt (_, vts, _, _, itm_) = if member op = vts vt then mk_e itm_ else [];

(* extract the environment from an item list; takes the variant with most items *)

fun environment itms = 

  let val vt = max_variant itms

  in (flat o (map (mk_en vt))) itms end;

(**)

fun o_model_values (Cor ((_, ts), _)) = ts

  | o_model_values (Syn _) = []

  | o_model_values (Typ _) = []

  | o_model_values (Inc ((_, ts), _)) = ts

  | o_model_values (Sup (_, ts)) = ts

  | o_model_values (Mis _) = []

  | o_model_values _ = raise ERROR "o_model_values: uncovered case in fun.def.";

val unique = Syntax.read_term\<^context> "UnIqE_tErM";

fun descriptor (Cor ((d ,_), _)) = d

  | descriptor (Syn _) = ((*tracing ("*** descriptor: Syn ("^c^")");*) unique)

  | descriptor (Typ _) = ((*tracing ("*** descriptor: Typ ("^c^")");*) unique)

  | descriptor (Inc ((d, _), _)) = d

  | descriptor (Sup (d, _)) = d

  | descriptor (Mis (d, _)) = d

  | descriptor _ = raise ERROR "descriptor: uncovered case in fun.def.";

(*val string_of_descr_values: term * (term list) -> string

  fun string_of_descr_values (d, ts) = pair2str (TermC.unparse_ERROR d, UnparseC.terms ts);*)

fun penvval_in (Cor ((d, _), (_, ts))) = [Input_Descript.join'''' (d, ts)]

  | penvval_in (Syn  (_)) = ((*tracing("*** penvval_in: Syn ("^c^")");*) [])

  | penvval_in (Typ  (_)) = ((*tracing("*** penvval_in: Typ ("^c^")");*) [])

  | penvval_in (Inc (_, (_, ts))) = ts

  | penvval_in (Sup _) = ((*tracing ("*** penvval_in: Sup " ^ string_of_descr_values dts);*) [])

  | penvval_in (Mis (_, _)) = ((*tracing ("*** penvval_in: Mis " ^

			pair2str(TermC.unparse_ERROR d, TermC.unparse_ERROR t));*) [])

	| penvval_in _ = raise ERROR "penvval_in: uncovered case in fun.def.";

fun variables itms = itms |> environment |> map snd

val unknown_descriptor = Syntax.read_term\<^context> "unknown::'a => unknow";

(* get a term from O_Model, notyet input in I_Model.

   the term from O_Model is thrown back to a string in order to reuse

   machinery for immediate input by the user. *)

fun get_field_term thy (_, _, _, d, ts) (_, _, _, fd, itm_) =

  (fd, ((UnparseC.term_in_thy thy) o Input_Descript.join) (d, subtract op = (o_model_values itm_) ts))

(* update the itm_ already input, all..from ori *)

fun ori_2itm itm_ pid all (id, vt, fd, d, ts) = 

  let 

    val ts' = union op = (o_model_values itm_) ts;

    val pval = [Input_Descript.join'''' (d, ts')]

	  (* WN.9.5.03: FIXXXME [#0, epsilon] here would upd_penv be called for [#0, epsilon] etc *)

    val complete = if eq_set op = (ts', all) then true else false

  in

    case itm_ of

      (Cor _) => 

        (if fd = "#undef" then (id, vt, complete, fd, Sup (d, ts')) 

	       else (id, vt, complete, fd, Cor ((d, ts'), (pid, pval))))

    | (Syn c) => raise ERROR ("ori_2itm wants to overwrite " ^ c)

    | (Typ c) => raise ERROR ("ori_2itm wants to overwrite " ^ c)

    | (Inc _) =>

      if complete

  	  then (id, vt, true, fd, Cor ((d, ts'), (pid, pval)))

  	  else (id, vt, false, fd, Inc ((d, ts'), (pid, pval)))

    | (Sup (d,ts')) => (*4.9.01 lost env*)

  	  (*if fd = "#undef" then*) (id,vt,complete,fd,Sup(d,ts'))

  	  (*else (id,vt,complete,fd,Cor((d,ts'),e))*)

      (* 28.1.00: not completely clear ---^^^ etc.*)

    | (Mis _) => (* 4.9.01: Mis just copied *)

       if complete

  		 then (id, vt, true, fd, Cor ((d,ts'), (pid, pval)))

  		 else (id, vt, false, fd, Inc ((d,ts'), (pid, pval)))

    | i => raise ERROR ("ori_2itm: uncovered case of " ^ feedback_to_string' i)

  end

fun eq1 d (_, (d', _)) = (d = d')

fun eq3 f d (_, _, _, f', itm_) = f = f' andalso d = (descriptor itm_) 

fun is_notyet_input ctxt itms all (i, v, f, d, ts) pbt =

  case find_first (eq1 d) pbt of

    SOME (_, (_, pid)) =>

      (case find_first (eq3 f d) itms of

        SOME (_, _, _, _, itm_) =>

          let val ts' = inter op = (o_model_values itm_) ts

          in 

            if subset op = (ts, ts') 

            then (((strs2str' o map (UnparseC.term ctxt)) ts') ^ " already input", empty_single)

	          else ("", ori_2itm itm_ pid all (i, v, f, d, subtract op = ts' ts))

	          end

	    | NONE => ("", ori_2itm (Inc ((TermC.empty, []), (pid, []))) pid all (i, v, f, d, ts)))

  | NONE => ("", ori_2itm (Sup (d, ts)) TermC.empty all (i, v, f, d, ts))

datatype add_single =

	Add of single   (* return-value of check_single *)

| Err of string   (* error-message                *)

(*

  Create feedback for input of TermC.as_string to m_field;

  check w.r.t. O_Model.T and Model_Pattern.T.

  In case of O_Model.T = [] (i.e. no data for user-guidance in Formalise.T)

  check_single is extremely permissive.

*)

(*will come directly from PIDE -----------------vvvvvvvvvvv

  in case t comes from Step.specify_do_next -----------vvv = Position.none*)

fun check_single ctxt m_field [] i_model m_patt (ct(*, pos*)) =

    let

      val i = 1 + (if i_model = [] then 0 else map #1 i_model |> maxl)

    (*/------------ replace by ParseC.term_position -----------\*)

      val t = Syntax.read_term ctxt ct

        handle ERROR msg => error (msg (*^ Position.here pos*))

    (*\------------ replace by ParseC.term_position -----------/*)

        (*NONE => Add (i, [], false, m_field, Syn ct)*)

      val (d, ts) = Input_Descript.split t

    in 

      if d = TermC.empty then

        Add (i, [], false, m_field, Mis (unknown_descriptor, hd ts)) 

      else

        (case find_first (eq1 d) m_patt of

          NONE => Add (i, [], true, m_field, Sup (d,ts))

        | SOME (f, (_, id)) =>

            let

              fun eq2 d (i, _, _, _, itm_) = d = (descriptor itm_) andalso i <> 0

            in

              case find_first (eq2 d) i_model of

                NONE => Add (i, [], true, f,Cor ((d, ts), (id, [Input_Descript.join'''' (d, ts)])))

              | SOME (i', _, _, _, itm_) => 

                  if Input_Descript.for_list d then 

                    let

                      val in_itm = o_model_values itm_

                      val ts' = union op = ts in_itm

                      val i'' = if in_itm = [] then i else i'

                    in Add (i'', [], true, f, Cor ((d, ts'), (id, [Input_Descript.join'''' (d, ts')])))end

                  else Add (i', [], true, f, Cor ((d, ts), (id, [Input_Descript.join'''' (d, ts)])))

            end)

    end

    (* for MethodC:   #undef  completed vvvvv vvvvvv term_as_string *)

    (*will come directly from PIDE ----------------------vvvvvvvvvvv*)

  | check_single ctxt m_field o_model i_model m_patt (str(*, pos*)) =

    let

      val (t as (descriptor $ _)) = Syntax.read_term ctxt str

        handle ERROR msg => error (msg (*^ Position.here pp*))

        (*old code: NONE => Err ("ERROR I_Model.check_single: syntax error in \"" ^ str ^ "\"")*)

    in 

        case Model_Pattern.get_field descriptor m_patt of

          NONE => Err ("ERROR I_Model.check_single: unknown descriptor \"" ^

            UnparseC.term ctxt descriptor ^ "\"")

        | SOME m_field' => 

          if m_field <> m_field' then

            Err ("ERROR I_Model.check_single: \"" ^ UnparseC.term ctxt t ^ "\"" ^

             "\" not for field \"" ^ m_field ^ "\"")

          else

            case O_Model.contains ctxt m_field o_model t of

              ("", ori', all) => 

                (case is_notyet_input ctxt i_model all ori' m_patt of

                   ("", itm) => Add itm

                 | (msg, _) => Err ("ERROR I_Model.check_single: is_notyet_input: " ^ msg))

            | (msg, _, _) => Err ("ERROR I_Model.check_single: contains: " ^ msg)

(* case parseNEW of    ..kept for understanding code..

      | SOME t => Err ("ERROR I_Model.check_single: impossible for input \"" ^

          UnparseC.term ctxt t ^ "\"")

*)

    end

(** add input **)

fun overwrite_ppc thy itm model =

  let 

    fun repl _ (_, _, _, _, itm_) [] =

        raise ERROR ("overwrite_ppc: " ^ feedback_to_string (Proof_Context.init_global thy) itm_

          ^ " not found")

      | repl model' itm (p :: model) =

	      if (#1 itm) = (#1 p)

	      then model' @ [itm] @ model

	      else repl (model' @ [p]) itm model

  in repl [] itm model end

(* find_first item with #1 equal to id *)

fun seek_ppc _ [] = NONE

  | seek_ppc id (p :: model) = if id = #1 (p: single) then SOME p else seek_ppc id model

(* 10.3.00: insert the already compiled itm into model;

   ev. filter_out  untouched (in FE: (0,...)) item related to insert-item *)

fun add_single thy itm model =

  let 

    fun eq_untouched d (0, _, _, _, itm_) = (d = descriptor itm_)

      | eq_untouched _ _ = false

    val model' = case seek_ppc (#1 itm) model of

      SOME _ => overwrite_ppc thy itm model (*itm updated in is_notyet_input WN.11.03*)

    | NONE => (model @ [itm])

  in filter_out (eq_untouched ((descriptor o #5) itm)) model' end

fun complete' pbt (i, v, f, d, ts) =

  case \<^try>\<open> (i, v, true, f, Cor ((d, ts),

      ((find_first ((fn descriptor => (fn (_, (d, _)) => descriptor = d)) d)) pbt |> the |> snd |> snd, ts)

    ))\<close> of

    SOME x => x

  | NONE => (i, v, true, f, Cor ((d, ts), (d, ts)))

(* filter out oris which have same description in itms *)

fun filter_outs oris [] = oris

  | filter_outs oris (i::itms) = 

    let

      val ors = filter_out ((curry op = ((descriptor o #5) i)) o (#4)) oris

    in

      filter_outs ors itms

    end

(* filter oris which are in pbt, too *)

fun filter_pbt oris pbt =

  let

    val dscs = map (fst o snd) pbt

  in

    filter ((member op= dscs) o (#4)) oris

  end

fun is_error (Cor _) = false

  | is_error (Sup _) = false

  | is_error (Inc _) = false

  | is_error (Mis _) = false

  | is_error _ = true

(*create output-string for itm_*)

fun to_p_model thy (Cor ((d, ts), _)) = UnparseC.term_in_thy thy (Input_Descript.join (d, ts))

  | to_p_model _ (Syn c) = c

  | to_p_model _ (Typ c) = c

  | to_p_model thy (Inc ((d, ts), _)) = UnparseC.term_in_thy thy (Input_Descript.join (d, ts))

  | to_p_model thy (Sup (d, ts)) = UnparseC.term_in_thy thy (Input_Descript.join (d, ts))

  | to_p_model thy (Mis (d, pid)) = UnparseC.term_in_thy thy d ^ " " ^ UnparseC.term_in_thy thy pid

  | to_p_model _ _ = raise ERROR "to_p_model: uncovered definition"

fun eq_dsc ((_, _, _, _, itm_), (_, _, _, _, iitm_)) = (descriptor itm_ = descriptor iitm_)

(* insert_ppc = add for appl_add', input_icalhd 11.03,

   handles superfluous items carelessly                       *)

fun add itm itms = if member eq_dsc itms itm then itms else itms @ [itm] (* @ new itm *)

(* combine itms from pbl + met and complete them wrt. pbt *)

(* FIXXXME.WN031205 complete doesnt handle incorrect itms !*)

fun complete oris pits mits met = 

  let

    val vat = max_variant pits;

    val itms = pits @ (filter ((member_swap op = vat) o (#2 )) mits)

    val ors = filter ((member_swap op= vat) o (#2)) oris

    val os = filter_outs ors itms (*WN.12.03?: does _NOT_ add itms from met ?!*)

  in

    itms @ (map (complete' met) os)

  end

(* complete model and guard of a calc-head *)

fun complete_method (oris, mpc, model, probl) =

  let

    val pits = filter_out ((curry op= false) o (#3)) probl

    val vat = if probl = [] then 1 else max_variant probl

    val pors = filter ((member_swap op = vat) o (#2)) oris

    val pors = filter_outs pors pits (*which are in pbl already*)

    val pors = (filter_pbt pors model) (*which are in pbt, too*)

    val pits = pits @ (map (complete' model) pors)

    val mits = complete oris pits [] mpc

  in (pits, mits) end

(* TODO: also check if all elements are I_Model.Cor *)

fun is_complete ([]: T) = false

  | is_complete itms = foldl and_ (true, (map #3 itms))

(**)end(**);