(* Title:  Specify/specify-step.sml

    Author: Walther Neuper

    (c) due to copyright terms

 Code for the specify-phase in analogy to structure Solve_Step for the solve-phase.

 *)

 signature SPECIFY_STEP =

 sig

   val check: Tactic.input -> Calc.T -> Applicable.T

   val add: Tactic.T -> Istate_Def.T * Proof.context -> Calc.T -> Test_Out.T

   val complete_for: MethodC.id -> Calc.T -> O_Model.T * Proof.context * I_Model.T

 end

 (**)

 structure Specify_Step(**): SPECIFY_STEP(**) =

 struct

 (**)

 fun complete_for mID (ctree, pos) =

   let

     val {origin = (o_model, o_refs, _), spec = refs, probl = i_prob, meth = met_imod, ctxt,

        ...} = Calc.specify_data (ctree, pos);

     val ctxt = Ctree.get_ctxt ctree pos

     val (dI, _, _) = References.select_input o_refs refs;

     val {model = m_patt, where_, where_rls, ...} = MethodC.from_store ctxt mID

     val {origin = (root_model, _, _), ...} = Calc.specify_data (ctree, ([], Pos.Und))

     val (o_model', ctxt') = O_Model.complete_for m_patt root_model (o_model, ctxt)

     val (_, (i_model, _)) = M_Match.by_i_models ctxt o_model' (i_prob, i_prob)

       (m_patt, where_, where_rls);

   in

     (o_model', ctxt', i_model)

   end

 (*

   check tactics (input by the user, mostly) for applicability

   and determine as much of the result of the tactic as possible initially.

 *)

 fun check (Tactic.Add_Find ct') _ = Applicable.Yes (Tactic.Add_Find' (ct', [(*filled later*)]))

     (*Add_.. should reject (dsc //) (see fmz=[] in sqrt*)

   | check (Tactic.Add_Given ct') _ = Applicable.Yes (Tactic.Add_Given' (ct', [(*filled later*)]))

   | check (Tactic.Add_Relation ct') _ = Applicable.Yes (Tactic.Add_Relation' (ct', [(*filled later*)]))

     (*required for corner cases, e.g. test setup in inssort.sml*)

   | check (Tactic.Del_Find ct') _ = Applicable.Yes (Tactic.Del_Find' ct')

   | check (Tactic.Del_Given ct') _ = Applicable.Yes (Tactic.Del_Given' ct')

   | check (Tactic.Del_Relation ct') _ = Applicable.Yes (Tactic.Del_Relation' ct')

   | check Tactic.Model_Problem (pt, pos as (p, _)) =

       let 

         val (ctxt, o_model, pI') = case Ctree.get_obj I pt p of

           Ctree.PblObj {ctxt, origin = (o_model, (_, pI', _), _), ...} => (ctxt, o_model, pI')

         | _ => raise ERROR "Specify_Step.check Model_Problem: uncovered case Ctree.get_obj"

 	      val {model = model_patt, ...} = Problem.from_store (Ctree.get_ctxt pt pos) pI'

 	      val pbl = I_Model.init ctxt o_model model_patt

       in Applicable.Yes (Tactic.Model_Problem' (pI', pbl, [])) end

   | check (Tactic.Refine_Problem pI) (pt, (p, _)) =

       let

         val (dI, dI', itms, ctxt) = case Ctree.get_obj I pt p of

             Ctree.PblObj {origin = (_, (dI, _, _), _), spec = (dI', _, _), probl = itms, ctxt, ...}

               => (dI, dI', itms, ctxt)

           | _ => raise ERROR "Specify_Step.check Refine_Problem: uncovered case Ctree.get_obj"

       	val thy = if dI' = ThyC.id_empty then dI else dI';

       in

         case Refine.problem (ThyC.get_theory ctxt thy) pI itms of

           NONE => Applicable.No

             (Tactic.input_to_string ctxt (Tactic.Refine_Problem pI) ^ " not applicable")

 	      | SOME (pI', (i_model, prec)) =>

       	   if pI' = pI

       	   then Applicable.No

       	     (Tactic.input_to_string ctxt (Tactic.Refine_Problem pI) ^ " not applicable")

       	   else Applicable.Yes (Tactic.Refine_Problem' (pI', (i_model, prec)))

     end

   | check (Tactic.Refine_Tacitly pI) (pt, (p, _)) =

      let 

        val (oris, ctxt) = case Ctree.get_obj I pt p of

          Ctree.PblObj {origin = (oris, _, _), ctxt, ...} => (oris, ctxt)

        | _ => raise ERROR "Specify_Step.check Refine_Tacitly: uncovered case Ctree.get_obj"

      in

        case Refine.by_o_model ctxt oris pI of

 	       SOME pblID => 

 	         Applicable.Yes (Tactic.Refine_Tacitly' (pI, pblID, ThyC.id_empty, MethodC.id_empty, [(*filled later*)]))

 	     | NONE => Applicable.No

 	         (Tactic.input_to_string ctxt (Tactic.Refine_Tacitly pI) ^ " not applicable")

      end

   | check (Tactic.Specify_Method mID) (ctree, pos) =

       let

         val (o_model, _, i_model) = complete_for mID (ctree, pos)

       in

         Applicable.Yes (Tactic.Specify_Method' (mID, o_model, i_model))

       end

   | check (Tactic.Specify_Problem pID) (pt, pos as (p, _)) =

       let

 		    val (oris,  pI,  pI', probl, meth, ctxt) = case Ctree.get_obj I pt p of

 		      Ctree.PblObj {origin = (oris, (_, pI, _), _), spec = (_, pI', _), probl, meth, ctxt, ...}

 		        => (oris,  pI,  pI', probl, meth, ctxt)

         | _ => raise ERROR "Specify_Step.check Specify_Problem: uncovered case Ctree.get_obj"

         val {model, where_, where_rls, ...} = Problem.from_store (Ctree.get_ctxt pt pos) pID;

         val (check, (i_model, preconds)) = if pI' = Problem.id_empty andalso pI = Problem.id_empty

           then (false,  (I_Model.init ctxt oris model, []: (bool * term) list))

           else M_Match.by_i_models ctxt oris (probl, meth) (model, where_, where_rls)

        in

          Applicable.Yes (Tactic.Specify_Problem' (pID, (check, (i_model, preconds))))

        end

   | check (Tactic.Specify_Theory dI)_ = Applicable.Yes (Tactic.Specify_Theory' dI)

   | check Tactic.Empty_Tac _ = Applicable.No "Empty_Tac is not applicable"

   | check tac (ctree, pos) =

     let

       val ctxt = Ctree.get_ctxt ctree pos

     in

       raise ERROR ("Specify_Step.check called for " ^

         Tactic.input_to_string ctxt tac ^ " at" ^ Pos.pos'2str pos)

     end;

 (* exceed line length, because result type will change *)

 fun add (Tactic.Model_Problem' (_, itms, met)) (_, ctxt) (pt, pos as (p, _)) =

       let

         val pt = Ctree.update_pbl pt p itms

   	    val pt = Ctree.update_met pt p met

       in

         (pos, [], Test_Out.PpcKF (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] []), pt)

       end

   | add (Tactic.Add_Given' (_, itmlist)) (_, ctxt) (pt, pos as (p, p_)) = 

       (pos, [], Test_Out.PpcKF (Test_Out.Upblmet,P_Model.from (Proof_Context.theory_of ctxt) [][]),

          case p_ of

            Pos.Pbl => Ctree.update_pbl pt p itmlist

   	     | Pos.Met => Ctree.update_met pt p itmlist

          | _ => raise ERROR ("uncovered case " ^ Pos.pos_2str p_))

   | add (Tactic.Add_Find' (_, itmlist)) (_, ctxt) (pt, pos as (p, p_)) = 

       (pos, [], (Test_Out.PpcKF (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] [])),

          case p_ of

            Pos.Pbl => Ctree.update_pbl pt p itmlist

   	     | Pos.Met => Ctree.update_met pt p itmlist

          | _ => raise ERROR ("uncovered case " ^ Pos.pos_2str p_))

   | add (Tactic.Add_Relation' (_, itmlist)) (_, ctxt) (pt, pos as (p, p_)) = 

       (pos, [],  Test_Out.PpcKF (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] []),

          case p_ of

            Pos.Pbl => Ctree.update_pbl pt p itmlist

   	     | Pos.Met => Ctree.update_met pt p itmlist

          | _ => raise ERROR ("uncovered case " ^ Pos.pos_2str p_))

   | add (Tactic.Specify_Theory' domID) (_, ctxt) (pt, pos as (p,_)) = 

       (pos, [] , Test_Out.PpcKF  (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] []),

         Ctree.update_domID pt p domID)

   | add (Tactic.Specify_Problem' (pI, (_, (itms, _)))) (_, ctxt) (pt, (p, _)) =

       let

         val pt = Ctree.update_pbl pt p itms

         val pt = Ctree.update_pblID pt p pI

       in

         ((p, Pos.Pbl), [], Test_Out.PpcKF (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] []), pt)

       end

   | add (Tactic.Specify_Method' (mID, oris, itms)) (_, ctxt) (pt, (p, _)) =

       let

         val pt = Ctree.update_oris pt p oris

         val pt = Ctree.update_met pt p itms

         val pt = Ctree.update_metID pt p mID

       in

         ((p, Pos.Met), [], Test_Out.PpcKF (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] []), pt)

       end

   | add (Tactic.Refine_Tacitly' (_, pIre, domID, metID, pbl)) (_, ctxt) (pt, pos as (p, _)) = 

       let

         val pt = Ctree.update_pbl pt p pbl

         val pt = Ctree.update_orispec pt p (domID, pIre, metID)

       in

         (pos, [], Test_Out.PpcKF (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] []), pt)

       end

   | add (Tactic.Refine_Problem' (pI, _)) (_, ctxt) (pt, pos as (p, _)) =

       let

         val (dI, _, mI) = Ctree.get_obj Ctree.g_spec pt p

         val pt = Ctree.update_spec pt p (dI, pI, mI)

       in

         (pos, [], Test_Out.PpcKF (Test_Out.Upblmet, P_Model.from (Proof_Context.theory_of ctxt) [] []), pt)

       end

   | add (Tactic.Begin_Trans' t) l (pt, pos as (p, Frm)) =

       let

         val (pt, c) = Ctree.cappend_form pt p l t

         val pt = Ctree.update_branch pt p Ctree.TransitiveB

         val p = (Pos.lev_on o Pos.lev_dn (* starts with [...,0] *)) p

         val (pt, c') = Ctree.cappend_form pt p l t

         val ctxt = Ctree.get_ctxt pt pos

       in

         ((p, Frm), c @ c', Test_Out.FormKF (UnparseC.term ctxt t), pt)

       end

   | add (Tactic.End_Trans' tasm) l (pt, (p, _)) = (* used at all ? *)

       let

         val p' = Pos.lev_up p

         val (pt, c) = Ctree.append_result pt p' l tasm Ctree.Complete

       in

         ((p', Pos.Res), c, Test_Out.FormKF "DUMMY" (*term2str t ..ERROR (t) has not been declared*), pt)

       end

   | add m' (_, ctxt) (_, pos) =

       raise ERROR ("Specify_Step.add: not impl.for " ^ Tactic.string_of ctxt m' ^ " at " ^ Pos.pos'2str pos)

 (**)end(**);