#!/usr/local/bin/perl

my $windows        = $ENV{'windir'} || $ENV{'WINDIR'};
my $listsep        = $ENV{'LISTSEP'} || ($windows? ';' : ':');
my $dirsep         = $ENV{'DIRSEP'} || ($windows? '\\' : '/');
my $fancy          = $windows? "\333" : '@';
my $joiner         = $windows? ''     : "\\\n"; #  "\\\n\t";

$USAGE="
USAGE:     $0 OPTIONS REGEXP
SYNOPSIS:  Print/verify ENV key/values that match REGEXP
AUTHOR: GPL(C) Mohsin Ahmed, http://www.cs.albany.edu/~mosh
NOTE: Like set | grep REGEXP, -dir checks dirs are readable.
      Cut/paste output into .bashrc and autoexec.bat.
OPTIONS:
       P  Prints key or value matching regexp P.
  -key=P  Prints key    =  P.
  -key P  Prints keys   =~ P.
  -Key P  Prints keys   !~ P.
  -val P  Prints values =~ P.
  -dir    Check dirs exists in value, eg. LIB, PATH, INCLUDE.
  -v      verbose
 EXAMPLE:
  setck
      LOGNAME=mosh
      HOME=/home/faculty/mosh  ...
      PATH=/etc:/usr/local/bin:/var
  setck '^PATH$'     Prints \$PATH
  setck 'M.*PATH'    Prints \$MANPATH
  setck -key=LIB      LIB=/sas/lib:/usr/lib
  setck -key HOME     HOME=/home/faculty/mosh
  setck -val bin      PATH=/etc:/usr/local/bin:/var
  setck -dir > settenv.bat && vi setenv.bat && settenv.bat
";

while( $_ = $ARGV[0], /^-/ ){
    shift; m/^--$/ && last;
    if( m/^-[?h]/i ){   print $USAGE; exit; }
    elsif( m/^-key=(.+)$/ ){   $mkey    = "\^$1\$"; undef $fancy; }
    elsif( m/^-key$/   ){   $mkey    = shift || die
                               "usage: -key PAT to pick\n"; }
    elsif( m/^-Key$/   ){   $notmkey = shift || die
                               "usage: -Key PAT to skip\n"; }
    elsif( m/^-val$/i  ){   $mval = shift || die
                               "usage: -val PAT to pick\n"; }
    elsif( m/^-dir$/   ){   $dirchk=1; undef $fancy; }
    elsif( m/^-v$/     ){   $verbose=1;   }
    else{                  die "Invalid option '$_', see -? for help.\n"; }
}


if( $pat = shift ){
    # $pat = sh2pat( $pat );
    warn "# grep( m/$pat/i, \%ENV )\n";
}

KEY: foreach $key (sort keys %ENV){
    my $val = $ENV{ $key };

    # pick the keys.

    next KEY  # Don't want to see the functions.
        if $val =~ m/}\s*\Z/;

    next KEY if  # User wants some keys?
        $mkey && $key !~ s/$mkey/$fancy$&$fancy/ig;

    next KEY if  # User doesn't want some keys?
        $notmkey && $key =~ m/$notmkey/i ;

    next KEY if  # User wants some values?
        $mval && $val =~ m/$mval/;

    next KEY  # Default is user wants anything matching his pat.
        if $pat && ($key !~ m/$pat/i ) && ( $val !~  m/$pat/i );

    next KEY  # User is doing -dir check and we don't care for rest.
        if $dirchk && $val !~ m,[/\\],;

    if( $dirchk ){
        my( $notfirstdir, %val );
        my @val = split( $listsep, $val );
        if( $windir ){
            @val = map( lc($_), @val );
            print "set $key=\n";
        }else{
            print "$key=\\\n";
        }
        foreach $dir (@val) {
            my $pd = '';
            if( $windir ){
                $pd .= "set $key=\%$key\%;$dir";
            }else{
                $pd .= ":$dir\\";
            }
            my $err;
            if( $dirchk ){
                $err .= " ** duplicate   "  if $val{ $dir }++ ;
                $err .= " ** trailing/   "  if $dir =~ s,[/\\]+$,,g;
                $err .= " ** unreadable  "
                         unless (-r $dir) or (not $dir) or ($dir =~ m/\%/);
                if( -f $dir ){
                $err .= " ** a file   "  
                }elsif(( ! -d $dir) and (-r $dir)){
                $err .= " ** not a dir   "  
                }
            }
            printf "%-50s %s\n", $pd, $err;
            $notfirstdir = 1;
        }
        print "\n";
    }else{
        $val =~ s/$listsep/$joiner$&/g;
        # print "\n", $key,'=',$joiner,$val,"\n";
        print $key,'=',$val,"\n";
    }
}

# EOF