(*  Title:      Pure/Isar/outer_syntax.ML

     ID:         $Id$

     Author:     Markus Wenzel, TU Muenchen

     License:    GPL (GNU GENERAL PUBLIC LICENSE)

 The global Isabelle/Isar outer syntax.

 *)

 signature BASIC_OUTER_SYNTAX =

 sig

   val main: unit -> unit

   val loop: unit -> unit

   val sync_main: unit -> unit

   val sync_loop: unit -> unit

 end;

 signature OUTER_SYNTAX =

 sig

   include BASIC_OUTER_SYNTAX

   structure Keyword:

     sig

       val control: string

       val diag: string

       val thy_begin: string

       val thy_switch: string

       val thy_end: string

       val thy_heading: string

       val thy_decl: string

       val thy_script: string

       val thy_goal: string

       val qed: string

       val qed_block: string

       val qed_global: string

       val prf_heading: string

       val prf_goal: string

       val prf_block: string

       val prf_open: string

       val prf_close: string

       val prf_chain: string

       val prf_decl: string

       val prf_asm: string

       val prf_asm_goal: string

       val prf_script: string

       val kinds: string list

     end

   type token

   type parser

   val command: string -> string -> string ->

     (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser

   val markup_command: IsarOutput.markup -> string -> string -> string ->

     (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser

   val improper_command: string -> string -> string ->

     (token list -> (Toplevel.transition -> Toplevel.transition) * token list) -> parser

   val is_keyword: string -> bool

   val dest_keywords: unit -> string list

   val dest_parsers: unit -> (string * string * string * bool) list

   val print_outer_syntax: unit -> unit

   val print_commands: Toplevel.transition -> Toplevel.transition

   val add_keywords: string list -> unit

   val add_parsers: parser list -> unit

   val check_text: string * Position.T -> bool -> Toplevel.state -> unit

   val deps_thy: string -> bool -> Path.T -> string list * Path.T list

   val load_thy: string -> bool -> bool -> Path.T -> unit

   val isar: bool -> bool -> unit Toplevel.isar

   val isar_readstring: Position.T -> string -> (string list) Toplevel.isar

   val read: string -> (string * OuterLex.token list * Toplevel.transition) list

 end;

 structure OuterSyntax: OUTER_SYNTAX =

 struct

 structure T = OuterLex;

 structure P = OuterParse;

 (** outer syntax **)

 (* command keyword classification *)

 structure Keyword =

 struct

   val control = "control";

   val diag = "diag";

   val thy_begin = "theory-begin";

   val thy_switch = "theory-switch";

   val thy_end = "theory-end";

   val thy_heading = "theory-heading";

   val thy_decl = "theory-decl";

   val thy_script = "theory-script";

   val thy_goal = "theory-goal";

   val qed = "qed";

   val qed_block = "qed-block";

   val qed_global = "qed-global";

   val prf_heading = "proof-heading";

   val prf_goal = "proof-goal";

   val prf_block = "proof-block";

   val prf_open = "proof-open";

   val prf_close = "proof-close";

   val prf_chain = "proof-chain";

   val prf_decl = "proof-decl";

   val prf_asm = "proof-asm";

   val prf_asm_goal = "proof-asm-goal";

   val prf_script = "proof-script";

   val kinds = [control, diag, thy_begin, thy_switch, thy_end, thy_heading, thy_decl, thy_script,

     thy_goal, qed, qed_block, qed_global, prf_heading, prf_goal, prf_block, prf_open, prf_close,

     prf_chain, prf_decl, prf_asm, prf_asm_goal, prf_script];

 end;

 (* parsers *)

 type token = T.token;

 type parser_fn = token list -> (Toplevel.transition -> Toplevel.transition) * token list;

 datatype parser =

   Parser of string * (string * string * IsarOutput.markup option) * bool * parser_fn;

 fun parser int_only markup name comment kind parse =

   Parser (name, (comment, kind, markup), int_only, parse);

 (* parse command *)

 local

 fun terminate false = Scan.succeed ()

   | terminate true = P.group "end of input" (Scan.option P.sync -- P.semicolon >> K ());

 fun trace false parse = parse

   | trace true parse = Scan.trace parse >> (fn (f, toks) => f o Toplevel.source toks);

 fun body cmd trc (name, _) =

   (case cmd name of

     Some (int_only, parse) =>

       P.!!! (Scan.prompt (name ^ "# ") (trace trc parse >> pair int_only))

   | None => sys_error ("no parser for outer syntax command " ^ quote name));

 in

 fun command do_terminate do_trace cmd =

   P.semicolon >> K None ||

   P.sync >> K None ||

   (P.position P.command :-- body cmd do_trace) --| terminate do_terminate

     >> (fn ((name, pos), (int_only, f)) =>

       Some (Toplevel.empty |> Toplevel.name name |> Toplevel.position pos |>

         Toplevel.interactive int_only |> f));

 end;

 (** global outer syntax **)

 local

 val global_lexicons = ref (Scan.empty_lexicon, Scan.empty_lexicon);

 val global_parsers =

   ref (Symtab.empty: (((string * string) * (bool * parser_fn)) * IsarOutput.markup option)

     Symtab.table);

 val global_markups = ref ([]: (string * IsarOutput.markup) list);

 fun change_lexicons f =

   let val lexs = f (! global_lexicons) in

     (case (op inter_string) (pairself Scan.dest_lexicon lexs) of

       [] => global_lexicons := lexs

     | bads => error ("Clash of outer syntax commands and keywords: " ^ commas_quote bads))

   end;

 fun get_markup (ms, (name, (_, Some m))) = (name, m) :: ms

   | get_markup (ms, _) = ms;

 fun make_markups () = global_markups := Symtab.foldl get_markup ([], ! global_parsers);

 fun change_parsers f = (Library.change global_parsers f; make_markups ());

 in

 (* access current syntax *)

 (*Note: the syntax for files is statically determined at the very

   beginning; for interactive processing it may change dynamically.*)

 fun get_lexicons () = ! global_lexicons;

 fun get_parsers () = ! global_parsers;

 fun get_parser () = apsome (#2 o #1) o curry Symtab.lookup (! global_parsers);

 fun is_markup kind name =

   (case assoc (! global_markups, name) of Some k => k = kind | None => false);

 fun markup kind = Scan.one (T.is_kind T.Command andf is_markup kind o T.val_of);

 (* augment syntax *)

 fun add_keywords keywords = change_lexicons (apfst (fn lex =>

   (Scan.extend_lexicon lex (map Symbol.explode keywords))));

 fun add_parser (tab, Parser (name, (comment, kind, markup), int_only, parse)) =

  (if is_none (Symtab.lookup (tab, name)) then ()

   else warning ("Redefined outer syntax command " ^ quote name);

   Symtab.update ((name, (((comment, kind), (int_only, parse)), markup)), tab));

 fun add_parsers parsers =

   (change_parsers (fn tab => foldl add_parser (tab, parsers));

     change_lexicons (apsnd (fn lex => Scan.extend_lexicon lex

       (map (fn Parser (name, _, _, _) => Symbol.explode name) parsers))));

 end;

 (* print syntax *)

 fun is_keyword s = Scan.is_literal (#1 (get_lexicons ())) (Symbol.explode s);

 fun dest_keywords () = Scan.dest_lexicon (#1 (get_lexicons ()));

 fun dest_parsers () =

   map (fn (name, (((cmt, kind), (int_only, _)), _)) => (name, cmt, kind, int_only))

     (Symtab.dest (get_parsers ()));

 fun print_outer_syntax () =

   let

     fun pretty_cmd (name, comment, _, _) =

       Pretty.block [Pretty.str (name ^ ":"), Pretty.brk 2, Pretty.str comment];

     val (int_cmds, cmds) = partition #4 (dest_parsers ());

   in

     [Pretty.strs ("syntax keywords:" :: map quote (dest_keywords ())),

       Pretty.big_list "proper commands:" (map pretty_cmd cmds),

       Pretty.big_list "improper commands (interactive-only):" (map pretty_cmd int_cmds)]

     |> Pretty.chunks |> Pretty.writeln

   end;

 val print_commands = Toplevel.imperative print_outer_syntax;

 (** toplevel parsing **)

 (* basic sources *)

 fun toplevel_source term trc do_recover cmd src =

   let

     val no_terminator =

       Scan.unless P.semicolon (Scan.one (T.not_sync andf T.not_eof));

     fun recover x = (Scan.prompt "recover# " (Scan.repeat no_terminator) >> K [None]) x;

   in

     src

     |> T.source_proper

     |> Source.source T.stopper

       (Scan.bulk (P.$$$ "--" -- P.!!! P.text >> K None || P.not_eof >> Some))

       (if do_recover then Some recover else None)

     |> Source.mapfilter I

     |> Source.source T.stopper (Scan.bulk (fn xs => P.!!! (command term trc (cmd ())) xs))

       (if do_recover then Some recover else None)

     |> Source.mapfilter I

   end;

 (* interactive source of toplevel transformers *)

 fun isar term no_pos =

   Source.tty

   |> Symbol.source true

   |> T.source true get_lexicons

     (if no_pos then Position.none else Position.line_name 1 "stdin")

   |> toplevel_source term false true get_parser;

 (* string source of transformers with trace (for Proof General) *)

 fun isar_readstring pos str =

   Source.of_string str

   |> Symbol.source false

   |> T.source false get_lexicons pos

   |> toplevel_source false true true get_parser;

 (* read text -- with trace of source *)

 fun read str =

   Source.of_string str

   |> Symbol.source false

   |> T.source false get_lexicons Position.none

   |> toplevel_source false true true get_parser

   |> Source.exhaust

   |> map (fn tr => (Toplevel.name_of tr, the (Toplevel.source_of tr), tr));

 (** read theory **)

 (* check_text *)

 fun check_text s true state = (IsarOutput.eval_antiquote (#1 (get_lexicons ())) state s; ())

   | check_text _ false _ = ();

 (* deps_thy *)

 fun deps_thy name ml path =

   let

     val src = Source.of_string (File.read path);

     val pos = Path.position path;

     val (name', parents, files) = ThyHeader.scan (src, pos);

     val ml_path = ThyLoad.ml_path name;

     val ml_file = if ml andalso is_some (ThyLoad.check_file ml_path) then [ml_path] else [];

   in

     if name <> name' then

       error ("Filename " ^ quote (Path.pack path) ^

         " does not agree with theory name " ^ quote name')

     else (parents, map (Path.unpack o #1) files @ ml_file)

   end;

 (* load_thy *)

 local

 fun try_ml_file name time =

   let

     val path = ThyLoad.ml_path name;

     val tr = Toplevel.imperative (fn () => ThyInfo.load_file time path);

     val tr_name = if time then "time_use" else "use";

   in

     if is_none (ThyLoad.check_file path) then ()

     else Toplevel.excursion [Toplevel.empty |> Toplevel.name tr_name |> tr]

   end;

 fun parse_thy src =

   src

   |> toplevel_source false false false (K (get_parser ()))

   |> Source.exhaust;

 fun run_thy name path =

   let

     val pos = Path.position path;

     val text = Library.untabify (explode (File.read path));

     val text_src = Source.of_list text;

     fun present_text () = Source.exhaust (Symbol.source false text_src);

   in

     Present.init_theory name;

     Present.verbatim_source name present_text;

     if ThyHeader.is_old (text_src, pos) then (ThySyn.load_thy name text;

       Present.old_symbol_source name present_text)   (*note: text presented twice*)

     else

       let

         val tok_src = text_src

           |> Symbol.source false

           |> T.source false (K (get_lexicons ())) pos

           |> Source.exhausted;

         val out = Toplevel.excursion_result

           (IsarOutput.parse_thy markup (#1 (get_lexicons ()))

             (parse_thy tok_src) tok_src);

       in Present.theory_output name (Buffer.content out) end

   end;

 in

 fun load_thy name ml time path =

  (if time then

     timeit (fn () =>

      (writeln ("\n**** Starting theory " ^ quote name ^ " ****");

       run_thy name path;

       writeln ("**** Finished theory " ^ quote name ^ " ****\n")))

   else run_thy name path;

   Context.context (ThyInfo.get_theory name);

   if ml then try_ml_file name time else ());

 end;

 (** the read-eval-print loop **)

 (* main loop *)

 fun gen_loop term no_pos =

  (Context.reset_context ();

   Toplevel.loop (isar term no_pos));

 fun gen_main term no_pos =

  (Toplevel.set_state Toplevel.toplevel;

   writeln (Session.welcome ());

   gen_loop term no_pos);

 fun main () = gen_main false false;

 fun loop () = gen_loop false false;

 fun sync_main () = gen_main true true;

 fun sync_loop () = gen_loop true true;

 (* help *)

 fun help () =

   writeln ("This is Isabelle's underlying ML system (" ^ ml_system ^ ");\n\

     \invoke 'Isar.loop();' to get back to the Isar read-eval-print loop.");

 (*final declarations of this structure!*)

 val command = parser false None;

 val markup_command = parser false o Some;

 val improper_command = parser true None;

 end;

 (*setup theory syntax dependent operations*)

 ThyLoad.deps_thy_fn := OuterSyntax.deps_thy;

 ThyLoad.load_thy_fn := OuterSyntax.load_thy;

 structure ThyLoad: THY_LOAD = ThyLoad;

 structure BasicOuterSyntax: BASIC_OUTER_SYNTAX = OuterSyntax;

 open BasicOuterSyntax;