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

  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_cnstrs dts =
  map (fn (_, _, _, constrs) => constrs) dts

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

fun get_cnstr_strs dts =
  map (fn (bn, _, _) => Binding.name_of bn) (flat (get_cnstrs dts))

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

ML {*
fun rawify_dts dt_names dts dts_env =
let
  val raw_dts = raw_dts dts_env dts
  val raw_dt_names = add_raws dt_names
in
  (raw_dt_names, raw_dts)
end 
*}

ML {*
fun rawify_bn_funs dts_env cnstrs_env bn_fun_env bn_funs bn_eqs =
let
  val bn_funs' = map (fn (bn, ty, mx) => 
    (raw_bind bn, replace_typ dts_env ty, mx)) bn_funs
  
  val bn_eqs' = map (fn (attr, trm) => 
    (attr, replace_term (cnstrs_env @ bn_fun_env) dts_env trm)) bn_eqs
in
  (bn_funs', bn_eqs') 
end 
*}

ML {* 
fun rawify_binds dts_env cnstrs_env bn_fun_env binds =
  map (map (map (map (fn (opt_trm, i, j) => 
    (Option.map (replace_term (cnstrs_env @ bn_fun_env) dts_env) opt_trm, i, j))))) binds
*}

ML {* 
fun add_primrec_wrapper funs eqs lthy = 
  if null funs then (([], []), lthy)
  else 
   let 
     val eqs' = map (fn (_, eq) => (Attrib.empty_binding, eq)) eqs
     val funs' = map (fn (bn, ty, mx) => (bn, SOME ty, mx)) funs
   in 
     Primrec.add_primrec funs' eqs' lthy
   end
*}

ML {*
fun add_datatype_wrapper dt_names dts =
let
  val conf = Datatype.default_config
in
  Local_Theory.theory_result (Datatype.add_datatype conf dt_names dts)
end
*}

ML {* 
fun raw_nominal_decls dts bn_funs bn_eqs binds lthy =
let
  val thy = ProofContext.theory_of lthy
  val thy_name = Context.theory_name thy

  val dt_names = map (fn (_, s, _, _) => Binding.name_of s) dts
  val dt_full_names = map (Long_Name.qualify thy_name) dt_names 
  val dt_full_names' = add_raws dt_full_names
  val dts_env = dt_full_names ~~ dt_full_names'

  val cnstrs = get_cnstr_strs dts
  val cnstrs_ty = get_typed_cnstrs dts
  val cnstrs_full_names = map (Long_Name.qualify thy_name) cnstrs
  val cnstrs_full_names' = map (fn (x, y) => Long_Name.qualify thy_name 
    (Long_Name.qualify (add_raw x) (add_raw y))) cnstrs_ty
  val cnstrs_env = cnstrs_full_names ~~ cnstrs_full_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_fun_full_env = map (pairself (Long_Name.qualify thy_name)) 
    (bn_fun_strs ~~ bn_fun_strs')
  
  val (raw_dt_names, raw_dts) = rawify_dts dt_names dts dts_env

  val (raw_bn_funs, raw_bn_eqs) = rawify_bn_funs dts_env cnstrs_env bn_fun_env bn_funs bn_eqs 
  
  val raw_binds = rawify_binds dts_env cnstrs_env bn_fun_full_env binds 
in
  lthy 
  |> add_datatype_wrapper raw_dt_names raw_dts 
  ||>> add_primrec_wrapper raw_bn_funs raw_bn_eqs
  ||>> pair raw_binds
end
*}

ML {* add_primrec_wrapper *}

ML {* 
fun nominal_datatype2 dts bn_funs bn_eqs binds lthy =
let
  val (((raw_dt_names, (raw_bn_funs, raw_bn_eqs)), raw_binds), lthy') =
    raw_nominal_decls dts bn_funs bn_eqs binds lthy
in
  ((raw_dt_names, raw_bn_funs, raw_bn_eqs, raw_binds), lthy')
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 find_all eq xs (k',i) = 
  maps (fn (k, (v1, v2)) => if eq (k, k') then [(v1, v2, i)] else []) xs
*}

ML {*
(* associates every SOME with the index in the list; drops NONEs *)
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_annos_binds dt_strs =
    map (map (fn (_, antys, _, bns) => (map fst antys, bns))) dt_strs

  fun prep_bn env bn_str =
    case (Syntax.read_term lthy bn_str) of
       Free (x, _) => (NONE, env_lookup env x)
     | Const (a, T) $ Free (x, _) => (SOME (Const (a, T)), env_lookup env x)
     | _ => error (bn_str ^ " not allowed as binding specification.");  
 
  fun prep_typ env (i, opt_name) = 
    case opt_name of
      NONE => []
    | SOME x => find_all (op=) env (x,i);
        
  (* annos - list of annotation for each type (either NONE or SOME fo a type *)
  
  fun prep_binds (annos, bind_strs) = 
  let
    val env = mk_env annos (* for every label the index *)
    val binds = map (fn (x, y) => (x, prep_bn env y)) bind_strs  
  in
    map_index (prep_typ binds) annos
  end

in
  map (map prep_binds) (extract_annos_binds (get_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
  
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