#!/usr/bin/perl
#erl -noshell -run ec -run erlang halt

# SPDX-FileCopyrightText: Chris Pressey, the original author of this work, has dedicated it to the public domain.
# For more information, please refer to <https://unlicense.org/>
# SPDX-License-Identifier: Unlicense

my $erlc = '/cygdrive/c/Program\ Files/erl5.3.6.3/bin/erlc.exe';

sub do_it($)
{
  my $cmdline = shift;
  print "$cmdline\n";
  my $errcode = system($cmdline);
  if ($errcode != 0) {
    die;
  }
}

sub traverse_dir($)
{
  my $dir = shift;
  #print "traversing $dir\n";
  my $cooked_dir = $dir;
  $cooked_dir = '.' if $dir eq '';
  opendir DIR, $cooked_dir;
  my @files = ();
  while (defined (my $file = readdir(DIR))) {
    next if $file eq '.' or $file eq '..' or $file eq '.svn';
    push @files, $file;
  }
  closedir DIR;

  foreach my $file (sort @files) {
    my $full_file = "$dir/$file";
    $full_file = $file if $dir eq '';

    if (-d $full_file) {
      traverse_dir($full_file);
    } elsif ($file =~ m|^(.*?)\.erl$|) {
      my $dest = "$1.beam";
      my $full_dest = "$dir/$1.beam";
      $full_dest =~ s/^src/ebin/;
      
      my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
          $atime,$src_mtime,$ctime,$blksize,$blocks)
          = stat($full_file);

      my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
          $atime,$dest_mtime,$ctime,$blksize,$blocks)
          = stat($full_dest);

      #print "$src_mtime, $dest_mtime\n";
      if ($force or (not defined $dest_mtime) or ($src_mtime > $dest_mtime)) {
        do_it "$erlc $full_file && mv $dest $full_dest";
      }
    }
  }
}

traverse_dir('src');