------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                             G N A T X R E F                              --
--                                                                          --
--                                 B o d y                                  --
--                                                                          --
--          Copyright (C) 1998-2021, Free Software Foundation, Inc.         --
--                                                                          --
-- GNAT is free software;  you can  redistribute it  and/or modify it under --
-- terms of the  GNU General Public License as published  by the Free Soft- --
-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
-- for  more details.  You should have  received  a copy of the GNU General --
-- Public License  distributed with GNAT; see file COPYING3.  If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license.          --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

with Opt;
with Osint;    use Osint;
with Types;    use Types;
with Switch;   use Switch;
with Xr_Tabls;
with Xref_Lib; use Xref_Lib;

with Ada.Command_Line;  use Ada.Command_Line;
with Ada.Strings.Fixed;
with Ada.Text_IO;       use Ada.Text_IO;

with GNAT.Command_Line; use GNAT.Command_Line;

with System.Strings;    use System.Strings;

procedure Gnatxref is
   Search_Unused   : Boolean := False;
   Local_Symbols   : Boolean := True;
   Prj_File        : File_Name_String;
   Prj_File_Length : Natural := 0;
   Usage_Error     : exception;
   Full_Path_Name  : Boolean := False;
   Vi_Mode         : Boolean := False;
   Read_Only       : Boolean := False;
   Have_File       : Boolean := False;
   Der_Info        : Boolean := False;

   RTS_Specified : String_Access := null;
   --  Used to detect multiple use of --RTS= switch

   EXT_Specified : String_Access := null;
   --  Used to detect multiple use of --ext= switch

   procedure Parse_Cmd_Line;
   --  Parse every switch on the command line

   procedure Usage;
   --  Display the usage

   procedure Write_Usage;
   pragma No_Return (Write_Usage);
   --  Print a small help page for program usage

   --------------------
   -- Parse_Cmd_Line --
   --------------------

   procedure Parse_Cmd_Line is

      procedure Check_Version_And_Help is new Check_Version_And_Help_G (Usage);

      --  Start of processing for Parse_Cmd_Line

   begin
      --  First check for --version or --help

      Check_Version_And_Help ("GNATXREF", "1998");

      loop
         case
           GNAT.Command_Line.Getopt
             ("a aI: aO: d f g h I: nostdinc nostdlib p: u v -RTS= -ext=")
         is
            when ASCII.NUL =>
               exit;

            when 'a' =>
               if GNAT.Command_Line.Full_Switch = "a" then
                  Read_Only := True;

               elsif GNAT.Command_Line.Full_Switch = "aI" then
                  Osint.Add_Src_Search_Dir (GNAT.Command_Line.Parameter);

               else
                  Osint.Add_Lib_Search_Dir (GNAT.Command_Line.Parameter);
               end if;

            when 'd' =>
               Der_Info := True;

            when 'f' =>
               Full_Path_Name := True;

            when 'g' =>
               Local_Symbols := False;

            when 'h' =>
               Write_Usage;

            when 'I' =>
               Osint.Add_Src_Search_Dir (GNAT.Command_Line.Parameter);
               Osint.Add_Lib_Search_Dir (GNAT.Command_Line.Parameter);

            when 'n' =>
               if GNAT.Command_Line.Full_Switch = "nostdinc" then
                  Opt.No_Stdinc := True;
               elsif GNAT.Command_Line.Full_Switch = "nostdlib" then
                  Opt.No_Stdlib := True;
               end if;

            when 'p' =>
               declare
                  S : constant String := GNAT.Command_Line.Parameter;
               begin
                  Prj_File_Length := S'Length;
                  Prj_File (1 .. Prj_File_Length) := S;
               end;

            when 'u' =>
               Search_Unused := True;
               Vi_Mode := False;

            when 'v' =>
               Vi_Mode := True;
               Search_Unused := False;

            --  The only switch starting with -- recognized is --RTS

            when '-' =>

               --  Check that it is the first time we see this switch

               if Full_Switch = "-RTS" then
                  if RTS_Specified = null then
                     RTS_Specified := new String'(GNAT.Command_Line.Parameter);

                  elsif RTS_Specified.all /= GNAT.Command_Line.Parameter then
                     Osint.Fail ("--RTS cannot be specified multiple times");
                  end if;

                  Opt.No_Stdinc  := True;
                  Opt.RTS_Switch := True;

                  declare
                     Src_Path_Name : constant String_Ptr :=
                                       Get_RTS_Search_Dir
                                         (GNAT.Command_Line.Parameter,
                                          Include);

                     Lib_Path_Name : constant String_Ptr :=
                                       Get_RTS_Search_Dir
                                         (GNAT.Command_Line.Parameter,
                                          Objects);

                  begin
                     if Src_Path_Name /= null
                       and then Lib_Path_Name /= null
                     then
                        Add_Search_Dirs (Src_Path_Name, Include);
                        Add_Search_Dirs (Lib_Path_Name, Objects);

                     elsif Src_Path_Name = null
                       and then Lib_Path_Name = null
                     then
                        Osint.Fail
                          ("RTS path not valid: missing adainclude and "
                           & "adalib directories");

                     elsif Src_Path_Name = null then
                        Osint.Fail
                          ("RTS path not valid: missing adainclude directory");

                     elsif Lib_Path_Name = null then
                        Osint.Fail
                          ("RTS path not valid: missing adalib directory");
                     end if;
                  end;

               elsif GNAT.Command_Line.Full_Switch = "-ext" then

                  --  Check that it is the first time we see this switch

                  if EXT_Specified = null then
                     EXT_Specified := new String'(GNAT.Command_Line.Parameter);

                  elsif EXT_Specified.all /= GNAT.Command_Line.Parameter then
                     Osint.Fail ("--ext cannot be specified multiple times");
                  end if;

                  if EXT_Specified'Length = Osint.ALI_Default_Suffix'Length
                  then
                     Osint.ALI_Suffix := EXT_Specified.all'Access;
                  else
                     Osint.Fail ("--ext argument must have 3 characters");
                  end if;
               end if;

            when others =>
               Try_Help;
               raise Usage_Error;
         end case;
      end loop;

      --  Get the other arguments

      loop
         declare
            S : constant String := GNAT.Command_Line.Get_Argument;

         begin
            exit when S'Length = 0;

            if Ada.Strings.Fixed.Index (S, ":") /= 0 then
               Ada.Text_IO.Put_Line
                 ("Only file names are allowed on the command line");
               Try_Help;
               raise Usage_Error;
            end if;

            Add_Xref_File (S);
            Have_File := True;
         end;
      end loop;

   exception
      when GNAT.Command_Line.Invalid_Switch =>
         Ada.Text_IO.Put_Line ("Invalid switch : "
                               & GNAT.Command_Line.Full_Switch);
         Try_Help;
         raise Usage_Error;

      when GNAT.Command_Line.Invalid_Parameter =>
         Ada.Text_IO.Put_Line ("Parameter missing for : "
                               & GNAT.Command_Line.Full_Switch);
         Try_Help;
         raise Usage_Error;
   end Parse_Cmd_Line;

   -----------
   -- Usage --
   -----------

   procedure Usage is
   begin
      Put_Line ("Usage: gnatxref [switches] file1 file2 ...");
      New_Line;
      Put_Line ("  file ... list of source files to xref, " &
                "including with'ed units");
      New_Line;
      Put_Line ("gnatxref switches:");
      Display_Usage_Version_And_Help;
      Put_Line ("   -a        Consider all files, even when the ali file is"
                & " readonly");
      Put_Line ("   -aIdir    Specify source files search path");
      Put_Line ("   -aOdir    Specify library/object files search path");
      Put_Line ("   -d        Output derived type information");
      Put_Line ("   -f        Output full path name");
      Put_Line ("   -g        Output information only for global symbols");
      Put_Line ("   -Idir     Like -aIdir -aOdir");
      Put_Line ("   -nostdinc Don't look for sources in the system default"
                & " directory");
      Put_Line ("   -nostdlib Don't look for library files in the system"
                & " default directory");
      Put_Line ("   --ext=xxx Specify alternate ali file extension");
      Put_Line ("   --RTS=dir specify the default source and object search"
                & " path");
      Put_Line ("   -p file   Use file as the configuration file");
      Put_Line ("   -u        List unused entities");
      Put_Line ("   -v        Print a 'tags' file for vi");
      New_Line;

   end Usage;

   -----------------
   -- Write_Usage --
   -----------------

   procedure Write_Usage is
   begin
      Display_Version ("GNATXREF", "1998");
      New_Line;
      Usage;
      raise Usage_Error;
   end Write_Usage;

begin
   Put_Line
     ("WARNING: gnatxref is obsolete and will be removed in the next release");
   Put_Line
     ("Consider using Libadalang or GNAT Studio python scripting instead");

   Parse_Cmd_Line;

   if not Have_File then
      if Argument_Count = 0 then
         Write_Usage;
      else
         Try_Help;
         raise Usage_Error;
      end if;
   end if;

   Xr_Tabls.Set_Default_Match (True);

   --  Find the project file

   if Prj_File_Length = 0 then
      Xr_Tabls.Create_Project_File
        (Default_Project_File (Osint.To_Host_Dir_Spec (".", False).all));
   else
      Xr_Tabls.Create_Project_File (Prj_File (1 .. Prj_File_Length));
   end if;

   --  Fill up the table

   Search_Xref (Local_Symbols, Read_Only, Der_Info);

   if Search_Unused then
      Print_Unused (Full_Path_Name);
   elsif Vi_Mode then
      Print_Vi (Full_Path_Name);
   else
      Print_Xref (Full_Path_Name);
   end if;

exception
   when Usage_Error =>
      null;
end Gnatxref;