(*  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;