#!/usr/bin/perl
use strict;
use File::Copy;
sub create_tmp_dir ($)
{
    # Create a temp directory, it will be removed when the script exits.
    my $base = shift;

    my $template = $base . ".XXXXXXXXXX";
    use File::Temp qw (tempdir);
    my $tmpdir = tempdir ($template, TMPDIR => 1, CLEANUP => 1);
    return $tmpdir;
}

my $arg=shift(@ARGV);
my $file;
if ($arg =~ m/\\input{([^\}]*)}/){
    $file=$1;
} else {
    $file=$arg;
}

my $stem=$file;
$stem =~ s/\.lhs$//;

print STDERR "using $stem as stem\n";

my $tmpdir= create_tmp_dir ("lhslatex");

my $old_dir=$ENV{PWD};

open (IN,"<$file") || die "$!";

chdir $tmpdir || die "$!";

# the aux file, and any other included files will be read from the original 
# directory

$ENV{TEXINPUTS}= $old_dir.':'.$ENV{TEXINPUTS};
print STDERR "TEXINPUTS=$ENV{TEXINPUTS}\n";

open (OUT,"|lhs2TeX - > $stem.tex") || die "$!";
while(<IN>){
    print OUT;
}
close OUT || die "$!";

my $command= $arg;

print STDERR "command = $command";
$command=~ s/\.lhs/.tex/;
print STDERR "command = $command";
system('pdflatex \''.$command.'\'');

move( $stem.".pdf", $old_dir) || die "$!";
move( $stem.".aux", $old_dir) || die "$!";