#!/usr/bin/perl
#
#  Copyright (c) 1997-2015
#  Ewgenij Gawrilow, Michael Joswig (Technische Universitaet Berlin, Germany)
#  http://www.polymake.org
#
#  This program is free software; you can redistribute it and/or modify it
#  under the terms of the GNU General Public License as published by the
#  Free Software Foundation; either version 2, or (at your option) any
#  later version: http://www.gnu.org/licenses/gpl.txt.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#-------------------------------------------------------------------------------

use strict;

my $Version="3.0";
my $InstallArch="/usr/lib/polymake";

sub usage {
  print STDERR <<'.';
usage: polymake-config --help | --version | [--debug] --OPTION

Print bits of polymake configuration useful to compose Makefiles
for programs linked with its callable library.

OPTION may be one of:
  --cc          print the name of C++ compiler and linker
  --cflags      print the C++ compiler flags without header paths
  --includes    print the C++ compiler flags for header paths
  --ldflags     print the linker flags
  --libs        print the libraries to link with
.
  exit(0);
}

@ARGV || usage;

my %conf;

if (-f "$InstallArch/conf.make" ) {
   open CONF, "$InstallArch/conf.make" or die "can't read $InstallArch/conf.make: $!\n";
   while (<CONF>) {
      if (/^(?:override\s+)?(\w+)\s*:=\s*(.*)\n/) {
         $conf{$1}=$2;
      }
   }
   close CONF;
} else {
  die "Installation error: configuration file $InstallArch/conf.make does not exist\n";
}

if ($conf{LDcallableFlags} eq "none") {
   die <<'.';
polymake has been built without callable library,
probably because of missing shared library libperl.
.
}

my $debug;
my $tmpdir;
foreach ($ENV{TMPDIR}, "/tmp", "/var/tmp", ".", $ENV{HOME}) {
   if (defined($_) && -d $_ && -w _ && -x _) {
      $tmpdir=$_; last;
   }
}
defined($tmpdir) or die <<'.';
Can't find any writable directory for temporary files;
Please set enviroment variable TMPDIR to an appropriate location.
.
my $tmpfile="$tmpdir/polymake-config-$$";
my $debug_asked;

while (defined ($_=shift)) {
   if ($_ eq "--debug") {
      if (defined $debug_asked) {
         usage;
      } else {
         $debug=1;
      }

   } elsif ($_ eq "--version") {
      print $Version, "\n";

   } elsif ($_ eq "--cc") {
      print $conf{CXX}, "\n";

   } elsif ($_ eq "--cflags") {
      $_="$conf{CsharedFlags} $conf{CXXflags}";
      if ($^O eq "darwin") {
         s/\$\{ARCHFLAGS\}/$conf{ARCHFLAGS}/;
      }
      s/-I\S+//g; s/^\s+//; s/\s+$//; s/\s{2,}/ /g;
      if ($debug_asked=defined($debug)) {
         print "$_ $conf{CXXDEBUG} -DPOLYMAKE_DEBUG=1\n";
      } else {
         print "$_ $conf{CXXOPT} -DPOLYMAKE_DEBUG=0\n";
      }

   } elsif ($_ eq "--includes") {
      my $inc=join(" ", grep { /^-I/ } split /\s+/, $conf{CXXflags});
      if ($inc !~ /(?:^|\s)-I$conf{InstallInc}(?:\s|$)/) {
         $inc="-I$conf{InstallInc} $inc";
      }
      open CF, ">$tmpfile.cc" or die "can't create temporary file $tmpfile.cc: $!\n";
      print CF "int main() { return 0; }\n";
      close CF;
      open CC, "$conf{CXX} -o $tmpfile.bin -v $tmpfile.cc 2>&1 |" or die "can't run C++ compiler $conf{CXX}: $!\n";
      while (<CC>) {
         last if (/^\#include.*starts here/i);
      }
      while (<CC>) {
         last if /end of search list/i;
         if (! /^\#/ && /(\S+)/) {
            my $dir=$1;
            $inc =~ s/(^|\s)-I$dir(\s\$)/$1$2/;
         }
      }
      close CC;
      $inc=~s/^\s+//; $inc=~s/\s+$//; $inc=~s/\s{2,}/ /g;
      print $inc, "\n";

   } elsif ($_ eq "--ldflags") {
      my $ldflags=$conf{LDflags};
      if ($ldflags !~ /(?:^|\s)-L$conf{InstallLib}(?:\s|$)/) {
         $ldflags="-L$conf{InstallLib} $ldflags";
      }
      my $add_rpath=1;
      open CF, ">$tmpfile.cc" or die "can't create temporary file $tmpfile.cc: $!\n";
      print CF "int main() { return 0; }\n";
      close CF;
      open CC, "$conf{CXX} -o $tmpfile.bin -v $tmpfile.cc 2>&1 |" or die "can't run C++ compiler $conf{CXX}: $!\n";
      while (<CC>) {
         if (/^LIBRARY_PATH=/i) {
            foreach my $dir (split /:/, $') {
               $ldflags =~ s/(^|\s)-L$dir(\s\$)/$1$2/;
               $add_rpath &&= $dir ne $conf{InstallLib};
            }
            last;
         }
      }
      close CC;
      if ($^O eq "darwin") {
         $ldflags="$conf{ARCHFLAGS} $ldflags -flat_namespace";
      } elsif ($add_rpath) {
         $ldflags.=" -Wl,-rpath,$conf{InstallLib}";
      }
      $ldflags=~s/^\s+//; $ldflags=~s/\s+$//; $ldflags=~s/\s{2,}/ /g;
      if ($debug_asked=defined($debug)) {
         print "$ldflags $conf{CXXDEBUG}\n";
      } else {
         print $ldflags, "\n";
      }
   } elsif ($_ eq "--libs") {
      my $libs="-lgmp $conf{Libs} $conf{LIBXML2_LIBS}";
      $libs=~s/\s+$//;
      if ($debug_asked=defined($debug)) {
         print "-lpolymake-d -lpolymake-apps $libs\n";
      } else {
         print "-lpolymake -lpolymake-apps $libs\n";
      }
   } else {
      usage;
   }
}

END {
   if (defined $tmpfile) {
      unlink $_ for glob "$tmpfile*";
   }
}

# Local Variables:
# mode: perl
# cperl-indent-level:3
# indent-tabs-mode:nil
# End:
