(**************************************************************************)
(*                                                                        *)
(*                                 OCaml                                  *)
(*                                                                        *)
(*             Xavier Leroy, projet Cristal, INRIA Rocquencourt           *)
(*                                                                        *)
(*   Copyright 1996 Institut National de Recherche en Informatique et     *)
(*     en Automatique.                                                    *)
(*                                                                        *)
(*   All rights reserved.  This file is distributed under the terms of    *)
(*   the GNU Lesser General Public License version 2.1, with the          *)
(*   special exception on linking described in the file LICENSE.          *)
(*                                                                        *)
(**************************************************************************)

(* The lexer generator. Command-line parsing. *)

open Syntax

let ml_automata = ref false
let source_name = ref None
let output_name = ref None

let usage = "usage: ocamllex [options] sourcefile"

let print_version_string () =
  print_string "The OCaml lexer generator, version ";
  print_string Sys.ocaml_version ; print_newline();
  exit 0

let print_version_num () =
  print_endline Sys.ocaml_version;
  exit 0

let specs =
  ["-ml", Arg.Set ml_automata,
    " Output code that does not use the Lexing module built-in automata \
     interpreter";
   "-o", Arg.String (fun x -> output_name := Some x),
    " <file>  Set output file name to <file>";
   "-q", Arg.Set Common.quiet_mode, " Do not display informational messages";
   "-v",  Arg.Unit print_version_string, " Print version and exit";
   "-version",  Arg.Unit print_version_string, " Print version and exit";
   "-vnum",  Arg.Unit print_version_num, " Print version number and exit";
  ]

let _ =
  Arg.parse
    specs
    (fun name -> source_name := Some name)
    usage


let main () =

  let source_name = match !source_name with
  | None -> Arg.usage specs usage ; exit 2
  | Some name -> name in
  let dest_name = match !output_name with
  | Some name -> name
  | None ->
      if Filename.check_suffix source_name ".mll" then
        Filename.chop_suffix source_name ".mll" ^ ".ml"
      else
        source_name ^ ".ml" in

  let ic = open_in_bin source_name in
  let oc = open_out dest_name in
  let tr = Common.open_tracker dest_name oc in
  let lexbuf = Lexing.from_channel ic in
  lexbuf.Lexing.lex_curr_p <-
    {Lexing.pos_fname = source_name; Lexing.pos_lnum = 1;
     Lexing.pos_bol = 0; Lexing.pos_cnum = 0};
  try
    let def = Parser.lexer_definition Lexer.main lexbuf in
    let (entries, transitions) = Lexgen.make_dfa def.entrypoints in
    if !ml_automata then begin
      Outputbis.output_lexdef
        ic oc tr
        def.header def.refill_handler entries transitions def.trailer
    end else begin
       let tables = Compact.compact_tables transitions in
       Output.output_lexdef ic oc tr
         def.header def.refill_handler tables entries def.trailer
    end;
    close_in ic;
    close_out oc;
    Common.close_tracker tr;
  with exn ->
    let bt = Printexc.get_raw_backtrace () in
    close_in ic;
    close_out oc;
    Common.close_tracker tr;
    Sys.remove dest_name;
    begin match exn with
    | Cset.Bad ->
        let p = Lexing.lexeme_start_p lexbuf in
        Printf.fprintf stderr
          "File \"%s\", line %d, character %d: character set expected.\n"
          p.Lexing.pos_fname p.Lexing.pos_lnum
          (p.Lexing.pos_cnum - p.Lexing.pos_bol)
    | Parsing.Parse_error ->
        let p = Lexing.lexeme_start_p lexbuf in
        Printf.fprintf stderr
          "File \"%s\", line %d, character %d: syntax error.\n"
          p.Lexing.pos_fname p.Lexing.pos_lnum
          (p.Lexing.pos_cnum - p.Lexing.pos_bol)
    | Lexer.Lexical_error(msg, file, line, col) ->
        Printf.fprintf stderr
          "File \"%s\", line %d, character %d: %s.\n"
          file line col msg
    | Lexgen.Memory_overflow ->
        Printf.fprintf stderr
          "File \"%s\":\n Position memory overflow, too many bindings\n"
          source_name
    | Output.Table_overflow ->
        Printf.fprintf stderr
          "File \"%s\":\ntransition table overflow, automaton is too big\n"
          source_name
    | _ ->
        Printexc.raise_with_backtrace exn bt
    end;
    exit 3

let _ = main (); exit 0
