theory Parser
imports "Nominal2_Atoms" "Nominal2_Eqvt" "Nominal2_Supp"
begin

atom_decl name


section{* Interface for nominal_datatype *}

text {*

Nominal-Datatype-part:


1nd Arg: (string list * binding * mixfix * (binding * typ list * mixfix) list) list
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
               type(s) to be defined             constructors list
               (ty args, name, syn)              (name, typs, syn)

Binder-Function-part:

2rd Arg: (binding * typ option * mixfix) list 
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^    
            binding function(s)           
              to be defined               
            (name, type, syn)             

3th Arg:  term list 
          ^^^^^^^^^
          the equations of the binding functions
          (Trueprop equations)
*}

ML {*

*}

text {*****************************************************}
ML {* 
(* nominal datatype parser *)
local
  structure P = OuterParse

  fun tuple ((x, y, z), u) = (x, y, z, u)
  fun tswap (((x, y), z), u) = (x, y, u, z)
in

val _ = OuterKeyword.keyword "bind"
val anno_typ = Scan.option (P.name --| P.$$$ "::") -- P.typ

(* binding specification *)
(* maybe use and_list *)
val bind_parser = 
  P.enum "," ((P.$$$ "bind" |-- P.term) -- (P.$$$ "in" |-- P.name) >> swap)

val constr_parser =
  P.binding -- Scan.repeat anno_typ

(* datatype parser *)
val dt_parser =
  (P.type_args -- P.binding -- P.opt_mixfix >> P.triple1) -- 
    (P.$$$ "=" |-- P.enum1 "|" (constr_parser -- bind_parser -- P.opt_mixfix >> tswap)) >> tuple

(* function equation parser *)
val fun_parser = 
  Scan.optional (P.$$$ "binder" |-- P.fixes -- SpecParse.where_alt_specs) ([],[])

(* main parser *)
val main_parser =
  (P.and_list1 dt_parser) -- fun_parser >> P.triple2

end
*}

(* adds "_raw" to the end of constants and types *)
ML {*
fun add_raw s = s ^ "_raw"
fun add_raws ss = map add_raw ss
fun raw_bind bn = Binding.suffix_name "_raw" bn

fun replace_str ss s = 
  case (AList.lookup (op=) ss s) of 
     SOME s' => s'
   | NONE => s

fun replace_typ ty_ss (Type (a, Ts)) = Type (replace_str ty_ss a, map (replace_typ ty_ss) Ts)
  | replace_typ ty_ss T = T  

fun raw_dts ty_ss dts =
let
  val ty_ss' = ty_ss ~~ (add_raws ty_ss)

  fun raw_dts_aux1 (bind, tys, mx) =
    (raw_bind bind, map (replace_typ ty_ss') tys, mx)

  fun raw_dts_aux2 (ty_args, bind, mx, constrs) =
    (ty_args, raw_bind bind, mx, map raw_dts_aux1 constrs)
in
  map raw_dts_aux2 dts
end

fun replace_aterm trm_ss (Const (a, T)) = Const (replace_str trm_ss a, T)
  | replace_aterm trm_ss (Free (a, T)) = Free (replace_str trm_ss a, T)
  | replace_aterm trm_ss trm = trm

fun replace_term trm_ss ty_ss trm =
  trm |> Term.map_aterms (replace_aterm trm_ss) |> map_types (replace_typ ty_ss) 
*}

ML {*
fun get_constrs dts =
  flat (map (fn (_, _, _, constrs) => constrs) dts)

fun get_typed_constrs dts =
  flat (map (fn (_, bn, _, constrs) => 
   (map (fn (bn', _, _) => (Binding.name_of bn, Binding.name_of bn')) constrs)) dts)

fun get_constr_strs dts =
  map (fn (bn, _, _) => Binding.name_of bn) (get_constrs dts)

fun get_bn_fun_strs bn_funs =
  map (fn (bn_fun, _, _) => Binding.name_of bn_fun) bn_funs
*}

ML {*
fun raw_dts_decl dt_names dts lthy =
let
  val thy = ProofContext.theory_of lthy
  val conf = Datatype.default_config

  val dt_names' = add_raws dt_names
  val dt_full_names = map (Sign.full_bname thy) dt_names 
  val dts' = raw_dts dt_full_names dts
in
  lthy
  |> Local_Theory.theory_result (Datatype.add_datatype conf dt_names' dts')
end 
*}

ML {*
fun raw_bn_fun_decl dt_names dts bn_funs bn_eqs lthy =
let
  val thy = ProofContext.theory_of lthy

  val dt_names' = add_raws dt_names
  val dt_full_names = map (Sign.full_bname thy) dt_names 
  val dt_full_names' = map (Sign.full_bname thy) dt_names' 
  val dt_env = dt_full_names ~~ dt_full_names'
  
  val ctrs_names = map (Sign.full_bname thy) (get_constr_strs dts)
  val ctrs_names' = map (fn (x, y) => (Sign.full_bname_path thy (add_raw x) (add_raw y))) 
    (get_typed_constrs dts)
  val ctrs_env = ctrs_names ~~ ctrs_names'

  val bn_fun_strs = get_bn_fun_strs bn_funs
  val bn_fun_strs' = add_raws bn_fun_strs
  val bn_fun_env = bn_fun_strs ~~ bn_fun_strs'
  
  val bn_funs' = map (fn (bn, ty, mx) => 
    (raw_bind bn, SOME (replace_typ dt_env ty), mx)) bn_funs
  
  val bn_eqs' = map (fn (_, trm) => 
    (Attrib.empty_binding, replace_term (ctrs_env @ bn_fun_env) dt_env trm)) bn_eqs
in
  if null bn_eqs 
  then (([], []), lthy)
  else Primrec.add_primrec bn_funs' bn_eqs' lthy 
end 
*}

ML {* 
fun nominal_datatype2 dts bn_funs bn_eqs binds lthy =
let
  val dts_names = map (fn (_, s, _, _) => Binding.name_of s) dts
in
  lthy
  |> raw_dts_decl dts_names dts
  ||>> raw_bn_fun_decl dts_names dts bn_funs bn_eqs
end
*}


ML {* 
(* parsing the datatypes and declaring *)
(* constructors in the local theory    *)
fun prepare_dts dt_strs lthy = 
let
  val thy = ProofContext.theory_of lthy
  
  fun mk_type full_tname tvrs =
    Type (full_tname, map (fn a => TVar ((a, 0), [])) tvrs)

  fun prep_cnstr lthy full_tname tvs (cname, anno_tys, mx, _) =
  let
    val tys = map (Syntax.read_typ lthy o snd) anno_tys
    val ty = mk_type full_tname tvs
  in
    ((cname, tys ---> ty, mx), (cname, tys, mx))
  end
  
  fun prep_dt lthy (tvs, tname, mx, cnstrs) = 
  let
    val full_tname = Sign.full_name thy tname
    val (cnstrs', cnstrs'') = 
      split_list (map (prep_cnstr lthy full_tname tvs) cnstrs)
  in
    (cnstrs', (tvs, tname, mx, cnstrs''))
  end 

  val (cnstrs, dts) = 
    split_list (map (prep_dt lthy) dt_strs)
in
  lthy
  |> Local_Theory.theory (Sign.add_consts_i (flat cnstrs))
  |> pair dts
end
*}

ML {*
(* parsing the binding function specification and *)
(* declaring the functions in the local theory    *)
fun prepare_bn_funs bn_fun_strs bn_eq_strs lthy =
let
  fun prep_bn_fun ((bn, T), mx) = (bn, T, mx) 

  val ((bn_funs, bn_eqs), _) = 
    Specification.read_spec bn_fun_strs bn_eq_strs lthy

  val bn_funs' = map prep_bn_fun bn_funs
in
  lthy
  |> Local_Theory.theory (Sign.add_consts_i bn_funs')
  |> pair (bn_funs', bn_eqs) 
end 
*}

ML {*
fun forth (_, _, _, x) = x

fun find_all eq xs k' = 
  maps (fn (k, v) => if eq (k, k') then [v] else []) xs
*}

ML {*
fun mk_env xs =
  let
    fun mapp (_: int) [] = []
      | mapp i (a :: xs) = 
         case a of
           NONE => mapp (i + 1) xs
         | SOME x => (x, i) :: mapp (i + 1) xs
  in mapp 0 xs end
*}

ML {*
fun env_lookup xs x =
  case AList.lookup (op =) xs x of
    SOME x => x
  | NONE => error ("cannot find " ^ x ^ " in the binding specification.")  
*}

ML {*
fun prepare_binds dt_strs lthy = 
let
  fun extract_cnstrs dt_strs =
    map ((map (fn (_, antys, _, bns) => (antys, bns))) o forth) dt_strs

  fun prep_bn env bn_str =
    case (Syntax.read_term lthy bn_str) of
       Free (x, _) => (env_lookup env x, NONE)
     | Const (a, T) $ Free (x, _) => (env_lookup env x, SOME (Const (a, T)))
     | _ => error (bn_str ^ " not allowed as binding specification.");  
 
  fun prep_typ env (opt_name, _) = 
    case opt_name of
      NONE => []
    | SOME x => find_all (op=) env x;
        
  fun prep_binds (anno_tys, bind_strs) = 
  let
    val env = mk_env (map fst anno_tys)
    val binds = map (fn (x, y) => (x, prep_bn env y)) bind_strs  
  in
    map (prep_typ binds) anno_tys
  end
in
  map (map prep_binds) (extract_cnstrs dt_strs)
end
*}

ML {*
fun nominal_datatype2_cmd (dt_strs, bn_fun_strs, bn_eq_strs) lthy =
let
  fun prep_typ (tvs, tname, mx, _) = (tname, length tvs, mx)

  val ((dts, (bn_fun, bn_eq)), binds) = 
    lthy 
    |> Local_Theory.theory (Sign.add_types (map prep_typ dt_strs))
    |> prepare_dts dt_strs
    ||>> prepare_bn_funs bn_fun_strs bn_eq_strs
    ||> prepare_binds dt_strs
  
  val _ = tracing (PolyML.makestring binds)
in
  nominal_datatype2 dts bn_fun bn_eq binds lthy |> snd
end
*}


(* Command Keyword *)

ML {*
let
   val kind = OuterKeyword.thy_decl
in
   OuterSyntax.local_theory "nominal_datatype" "test" kind 
     (main_parser >> nominal_datatype2_cmd)
end
*}


end