(*  Title:      Pure/Syntax/printer.ML

    Author:     Tobias Nipkow and Markus Wenzel, TU Muenchen

Pretty printing of asts, terms, types and print (ast) translation.

*)

signature PRINTER0 =

sig

  val show_brackets: bool Unsynchronized.ref

  val show_sorts: bool Unsynchronized.ref

  val show_types: bool Unsynchronized.ref

  val show_no_free_types: bool Unsynchronized.ref

  val show_all_types: bool Unsynchronized.ref

  val show_structs: bool Unsynchronized.ref

  val pp_show_brackets: Pretty.pp -> Pretty.pp

end;

signature PRINTER =

sig

  include PRINTER0

  val sort_to_ast: Proof.context ->

    (string -> (Proof.context -> bool -> typ -> term list -> term) list) -> sort -> Ast.ast

  val typ_to_ast: Proof.context ->

    (string -> (Proof.context -> bool -> typ -> term list -> term) list) -> typ -> Ast.ast

  val term_to_ast: {structs: string list, fixes: string list} -> string list -> Proof.context ->

    (string -> (Proof.context -> bool -> typ -> term list -> term) list) -> term -> Ast.ast

  type prtabs

  val empty_prtabs: prtabs

  val update_prtabs: string -> Syn_Ext.xprod list -> prtabs -> prtabs

  val remove_prtabs: string -> Syn_Ext.xprod list -> prtabs -> prtabs

  val merge_prtabs: prtabs -> prtabs -> prtabs

  val pretty_term_ast: {extern_class: string -> xstring, extern_type: string -> xstring,

      extern_const: string -> xstring} -> Proof.context -> bool -> prtabs ->

    (string -> (Proof.context -> Ast.ast list -> Ast.ast) list) ->

    (string -> (Proof.context -> string -> Pretty.T) option) -> Ast.ast -> Pretty.T list

  val pretty_typ_ast: {extern_class: string -> xstring, extern_type: string -> xstring} ->

    Proof.context -> bool -> prtabs ->

    (string -> (Proof.context -> Ast.ast list -> Ast.ast) list) ->

    (string -> (Proof.context -> string -> Pretty.T) option) -> Ast.ast -> Pretty.T list

end;

structure Printer: PRINTER =

struct

(** options for printing **)

val show_types = Unsynchronized.ref false;

val show_sorts = Unsynchronized.ref false;

val show_brackets = Unsynchronized.ref false;

val show_no_free_types = Unsynchronized.ref false;

val show_all_types = Unsynchronized.ref false;

val show_structs = Unsynchronized.ref false;

fun pp_show_brackets pp = Pretty.pp (setmp_CRITICAL show_brackets true (Pretty.term pp),

  Pretty.typ pp, Pretty.sort pp, Pretty.classrel pp, Pretty.arity pp);

(** misc utils **)

(* apply print (ast) translation function *)

fun apply_trans ctxt fns args =

  let

    fun app_first [] = raise Match

      | app_first (f :: fs) = f ctxt args handle Match => app_first fs;

  in app_first fns end;

fun apply_typed x y fs = map (fn f => fn ctxt => f ctxt x y) fs;

(* simple_ast_of *)

fun simple_ast_of (Const (c, _)) = Ast.Constant c

  | simple_ast_of (Free (x, _)) = Ast.Variable x

  | simple_ast_of (Var (xi, _)) = Ast.Variable (Term.string_of_vname xi)

  | simple_ast_of (t as _ $ _) =

      let val (f, args) = strip_comb t in

        Ast.mk_appl (simple_ast_of f) (map simple_ast_of args)

      end

  | simple_ast_of (Bound i) = Ast.Variable ("B." ^ string_of_int i)

  | simple_ast_of (Abs _) = sys_error "simple_ast_of: Abs";

(** sort_to_ast, typ_to_ast **)

fun ast_of_termT ctxt trf tm =

  let

    fun ast_of (t as Const ("_tfree", _) $ Free _) = simple_ast_of t

      | ast_of (t as Const ("_tvar", _) $ Var _) = simple_ast_of t

      | ast_of (Const (a, _)) = trans a []

      | ast_of (t as _ $ _) =

          (case strip_comb t of

            (Const (a, _), args) => trans a args

          | (f, args) => Ast.Appl (map ast_of (f :: args)))

      | ast_of t = simple_ast_of t

    and trans a args =

      ast_of (apply_trans ctxt (apply_typed false dummyT (trf a)) args)

        handle Match => Ast.mk_appl (Ast.Constant a) (map ast_of args);

  in ast_of tm end;

fun sort_to_ast ctxt trf S = ast_of_termT ctxt trf (Type_Ext.term_of_sort S);

fun typ_to_ast ctxt trf T = ast_of_termT ctxt trf (Type_Ext.term_of_typ (! show_sorts) T);

(** term_to_ast **)

fun ast_of_term idents consts ctxt trf

    show_all_types no_freeTs show_types show_sorts show_structs tm =

  let

    val {structs, fixes} = idents;

    fun mark_atoms ((t as Const (c, T)) $ u) =

          if member (op =) Syn_Ext.standard_token_markers c

          then t $ u else mark_atoms t $ mark_atoms u

      | mark_atoms (t $ u) = mark_atoms t $ mark_atoms u

      | mark_atoms (Abs (x, T, t)) = Abs (x, T, mark_atoms t)

      | mark_atoms (t as Const (c, T)) =

          if member (op =) consts c then t

          else Const (Lexicon.mark_const c, T)

      | mark_atoms (t as Free (x, T)) =

          let val i = find_index (fn s => s = x) structs + 1 in

            if i = 0 andalso member (op =) fixes x then

              Const (Lexicon.mark_fixed x, T)

            else if i = 1 andalso not show_structs then

              Lexicon.const "_struct" $ Lexicon.const "_indexdefault"

            else Lexicon.const "_free" $ t

          end

      | mark_atoms (t as Var (xi, T)) =

          if xi = Syn_Ext.dddot_indexname then Const ("_DDDOT", T)

          else Lexicon.const "_var" $ t

      | mark_atoms a = a;

    fun prune_typs (t_seen as (Const _, _)) = t_seen

      | prune_typs (t as Free (x, ty), seen) =

          if ty = dummyT then (t, seen)

          else if no_freeTs orelse member (op aconv) seen t then (Lexicon.free x, seen)

          else (t, t :: seen)

      | prune_typs (t as Var (xi, ty), seen) =

          if ty = dummyT then (t, seen)

          else if no_freeTs orelse member (op aconv) seen t then (Lexicon.var xi, seen)

          else (t, t :: seen)

      | prune_typs (t_seen as (Bound _, _)) = t_seen

      | prune_typs (Abs (x, ty, t), seen) =

          let val (t', seen') = prune_typs (t, seen);

          in (Abs (x, ty, t'), seen') end

      | prune_typs (t1 $ t2, seen) =

          let

            val (t1', seen') = prune_typs (t1, seen);

            val (t2', seen'') = prune_typs (t2, seen');

          in (t1' $ t2', seen'') end;

    fun ast_of tm =

      (case strip_comb tm of

        (t as Abs _, ts) => Ast.mk_appl (ast_of (Syn_Trans.abs_tr' t)) (map ast_of ts)

      | ((c as Const ("_free", _)), Free (x, T) :: ts) =>

          Ast.mk_appl (constrain (c $ Lexicon.free x) T) (map ast_of ts)

      | ((c as Const ("_var", _)), Var (xi, T) :: ts) =>

          Ast.mk_appl (constrain (c $ Lexicon.var xi) T) (map ast_of ts)

      | ((c as Const ("_bound", _)), Free (x, T) :: ts) =>

          Ast.mk_appl (constrain (c $ Lexicon.free x) T) (map ast_of ts)

      | (Const ("_idtdummy", T), ts) =>

          Ast.mk_appl (constrain (Lexicon.const "_idtdummy") T) (map ast_of ts)

      | (const as Const (c, T), ts) =>

          if show_all_types

          then Ast.mk_appl (constrain const T) (map ast_of ts)

          else trans c T ts

      | (t, ts) => Ast.mk_appl (simple_ast_of t) (map ast_of ts))

    and trans a T args =

      ast_of (apply_trans ctxt (apply_typed show_sorts T (trf a)) args)

        handle Match => Ast.mk_appl (Ast.Constant a) (map ast_of args)

    and constrain t T =

      if show_types andalso T <> dummyT then

        Ast.Appl [Ast.Constant Syn_Ext.constrainC, simple_ast_of t,

          ast_of_termT ctxt trf (Type_Ext.term_of_typ show_sorts T)]

      else simple_ast_of t;

  in

    tm

    |> Syn_Trans.prop_tr'

    |> show_types ? (#1 o prune_typs o rpair [])

    |> mark_atoms

    |> ast_of

  end;

fun term_to_ast idents consts ctxt trf tm =

  ast_of_term idents consts ctxt trf (! show_all_types) (! show_no_free_types)

    (! show_types orelse ! show_sorts orelse ! show_all_types) (! show_sorts) (! show_structs) tm;

(** type prtabs **)

datatype symb =

  Arg of int |

  TypArg of int |

  String of string |

  Space of string |

  Break of int |

  Block of int * symb list;

type prtabs = (string * ((symb list * int * int) list) Symtab.table) list;

fun mode_tab prtabs mode = the_default Symtab.empty (AList.lookup (op =) prtabs mode);

fun mode_tabs prtabs modes = map_filter (AList.lookup (op =) prtabs) (modes @ [""]);

(* xprod_to_fmt *)

fun xprod_to_fmt (Syn_Ext.XProd (_, _, "", _)) = NONE

  | xprod_to_fmt (Syn_Ext.XProd (_, xsymbs, const, pri)) =

      let

        fun arg (s, p) =

          (if s = "type" then TypArg else Arg)

          (if Lexicon.is_terminal s then Syn_Ext.max_pri else p);

        fun xsyms_to_syms (Syn_Ext.Delim s :: xsyms) =

              apfst (cons (String s)) (xsyms_to_syms xsyms)

          | xsyms_to_syms (Syn_Ext.Argument s_p :: xsyms) =

              apfst (cons (arg s_p)) (xsyms_to_syms xsyms)

          | xsyms_to_syms (Syn_Ext.Space s :: xsyms) =

              apfst (cons (Space s)) (xsyms_to_syms xsyms)

          | xsyms_to_syms (Syn_Ext.Bg i :: xsyms) =

              let

                val (bsyms, xsyms') = xsyms_to_syms xsyms;

                val (syms, xsyms'') = xsyms_to_syms xsyms';

              in

                (Block (i, bsyms) :: syms, xsyms'')

              end

          | xsyms_to_syms (Syn_Ext.Brk i :: xsyms) =

              apfst (cons (Break i)) (xsyms_to_syms xsyms)

          | xsyms_to_syms (Syn_Ext.En :: xsyms) = ([], xsyms)

          | xsyms_to_syms [] = ([], []);

        fun nargs (Arg _ :: syms) = nargs syms + 1

          | nargs (TypArg _ :: syms) = nargs syms + 1

          | nargs (String _ :: syms) = nargs syms

          | nargs (Space _ :: syms) = nargs syms

          | nargs (Break _ :: syms) = nargs syms

          | nargs (Block (_, bsyms) :: syms) = nargs syms + nargs bsyms

          | nargs [] = 0;

      in

        (case xsyms_to_syms xsymbs of

          (symbs, []) => SOME (const, (symbs, nargs symbs, pri))

        | _ => sys_error "xprod_to_fmt: unbalanced blocks")

      end;

(* empty, extend, merge prtabs *)

val empty_prtabs = [];

fun update_prtabs mode xprods prtabs =

  let

    val fmts = map_filter xprod_to_fmt xprods;

    val tab' = fold (Symtab.update_list (op =)) fmts (mode_tab prtabs mode);

  in AList.update (op =) (mode, tab') prtabs end;

fun remove_prtabs mode xprods prtabs =

  let

    val tab = mode_tab prtabs mode;

    val fmts = map_filter (fn xprod as Syn_Ext.XProd (_, _, c, _) =>

      if null (Symtab.lookup_list tab c) then NONE

      else xprod_to_fmt xprod) xprods;

    val tab' = fold (Symtab.remove_list (op =)) fmts tab;

  in AList.update (op =) (mode, tab') prtabs end;

fun merge_prtabs prtabs1 prtabs2 =

  let

    val modes = distinct (op =) (map fst (prtabs1 @ prtabs2));

    fun merge m = (m, Symtab.merge_list (op =) (mode_tab prtabs1 m, mode_tab prtabs2 m));

  in map merge modes end;

(** pretty term or typ asts **)

fun is_chain [Block (_, pr)] = is_chain pr

  | is_chain [Arg _] = true

  | is_chain _  = false;

fun pretty extern ctxt tabs trf tokentrf type_mode curried ast0 p0 =

  let

    val {extern_class, extern_type, extern_const} = extern;

    fun token_trans a x =

      (case tokentrf a of

        NONE =>

          if member (op =) Syn_Ext.standard_token_classes a

          then SOME (Pretty.str x) else NONE

      | SOME f => SOME (f ctxt x));

    (*default applications: prefix / postfix*)

    val appT =

      if type_mode then Type_Ext.tappl_ast_tr'

      else if curried then Syn_Trans.applC_ast_tr'

      else Syn_Trans.appl_ast_tr';

    fun synT _ ([], args) = ([], args)

      | synT markup (Arg p :: symbs, t :: args) =

          let val (Ts, args') = synT markup (symbs, args);

          in (astT (t, p) @ Ts, args') end

      | synT markup (TypArg p :: symbs, t :: args) =

          let

            val (Ts, args') = synT markup (symbs, args);

          in

            if type_mode then (astT (t, p) @ Ts, args')

            else (pretty extern ctxt tabs trf tokentrf true curried t p @ Ts, args')

          end

      | synT markup (String s :: symbs, args) =

          let val (Ts, args') = synT markup (symbs, args);

          in (markup (Pretty.str s) :: Ts, args') end

      | synT markup (Space s :: symbs, args) =

          let val (Ts, args') = synT markup (symbs, args);

          in (Pretty.str s :: Ts, args') end

      | synT markup (Block (i, bsymbs) :: symbs, args) =

          let

            val (bTs, args') = synT markup (bsymbs, args);

            val (Ts, args'') = synT markup (symbs, args');

            val T =

              if i < 0 then Pretty.unbreakable (Pretty.block bTs)

              else Pretty.blk (i, bTs);

          in (T :: Ts, args'') end

      | synT markup (Break i :: symbs, args) =

          let

            val (Ts, args') = synT markup (symbs, args);

            val T = if i < 0 then Pretty.fbrk else Pretty.brk i;

          in (T :: Ts, args') end

    and parT markup (pr, args, p, p': int) = #1 (synT markup

          (if p > p' orelse

            (! show_brackets andalso p' <> Syn_Ext.max_pri andalso not (is_chain pr))

            then [Block (1, Space "(" :: pr @ [Space ")"])]

            else pr, args))

    and atomT a = a |> Lexicon.unmark

     {case_class = fn c => Pretty.mark (Markup.tclass c) (Pretty.str (extern_class c)),

      case_type = fn c => Pretty.mark (Markup.tycon c) (Pretty.str (extern_type c)),

      case_const = fn c => Pretty.mark (Markup.const c) (Pretty.str (extern_const c)),

      case_fixed = fn x => the (token_trans "_free" x),

      case_default = Pretty.str}

    and prefixT (_, a, [], _) = [atomT a]

      | prefixT (c, _, args, p) = astT (appT (c, args), p)

    and splitT 0 ([x], ys) = (x, ys)

      | splitT 0 (rev_xs, ys) = (Ast.Appl (rev rev_xs), ys)

      | splitT n (rev_xs, y :: ys) = splitT (n - 1) (y :: rev_xs, ys)

    and combT (tup as (c, a, args, p)) =

      let

        val nargs = length args;

        val markup = a |> Lexicon.unmark

         {case_class = Pretty.mark o Markup.tclass,

          case_type = Pretty.mark o Markup.tycon,

          case_const = Pretty.mark o Markup.const,

          case_fixed = Pretty.mark o Markup.fixed,

          case_default = K I};

        (*find matching table entry, or print as prefix / postfix*)

        fun prnt ([], []) = prefixT tup

          | prnt ([], tb :: tbs) = prnt (Symtab.lookup_list tb a, tbs)

          | prnt ((pr, n, p') :: prnps, tbs) =

              if nargs = n then parT markup (pr, args, p, p')

              else if nargs > n andalso not type_mode then

                astT (appT (splitT n ([c], args)), p)

              else prnt (prnps, tbs);

      in

        (case tokentrT a args of

          SOME prt => [prt]

        | NONE => astT (apply_trans ctxt (trf a) args, p) handle Match => prnt ([], tabs))

      end

    and tokentrT a [Ast.Variable x] = token_trans a x

      | tokentrT _ _ = NONE

    and astT (c as Ast.Constant a, p) = combT (c, a, [], p)

      | astT (Ast.Variable x, _) = [Pretty.str x]

      | astT (Ast.Appl ((c as Ast.Constant a) :: (args as _ :: _)), p) = combT (c, a, args, p)

      | astT (Ast.Appl (f :: (args as _ :: _)), p) = astT (appT (f, args), p)

      | astT (ast as Ast.Appl _, _) = raise Ast.AST ("pretty: malformed ast", [ast]);

  in astT (ast0, p0) end;

(* pretty_term_ast *)

fun pretty_term_ast extern ctxt curried prtabs trf tokentrf ast =

  pretty extern ctxt (mode_tabs prtabs (print_mode_value ()))

    trf tokentrf false curried ast 0;

(* pretty_typ_ast *)

fun pretty_typ_ast {extern_class, extern_type} ctxt _ prtabs trf tokentrf ast =

  pretty {extern_class = extern_class, extern_type = extern_type, extern_const = I}

    ctxt (mode_tabs prtabs (print_mode_value ()))

    trf tokentrf true false ast 0;

end;