Why my command line arguments throw an error?

Use of uninitialized value in opendir at ./generate.pl line 50.
Use of uninitialized value in concatenation (.) or string at ./generate.pl line 50.
Can't open : No such file or directory at ./generate.pl line 50.

./generate.pl -prjroot "/home/rpsa/EMO/ct_space" -outdir "/home/rpsa/output" -mapfile "/home/rpsa/EMO/mapfile.txt"

#!/usr/local/bin/perl
use strict;
use warnings 'all';
#use CGI qw(:all);
#generate the user file arguments

use File::Path       qw( make_path );
use File::Copy  qw( copy move);
use File::Find::Rule qw( );
use File::Remove();
use Cwd qw(getcwd);
use File::Basename;
use File::Copy ();
use File::Remove();
use File::Basename;
 
 use Getopt::Long 'GetOptions';
GetOptions(
    'prjroot=s' => \my $input_dir,
    'outdir=s'  => \my $output_dir,
   'mapfile=s' => \my $mapfile,
);
##COPYING THE CONFIG FILES FROM SOURCE TO DESTINATION### 
my %created;
for my $in (
   File::Find::Rule
   ->file()
   ->name(qr/^[^.].*\.config$/)
   ->in($input_dir)
) {
   my $match_file = substr($in, length($input_dir) + 1); 
   my ($match_dir) = $match_file =~ m{^(.*)/} ? $1 : '.';
   my $out_dir = $output_dir . '/' . $match_dir;
   my $out     = $output_dir . '/' . $match_file;
   make_path($out_dir) if !$created{$out_dir}++;
   copy($in, $out);
}
##READ THE TEXT FILE AND RENAME THE DIRECTORIES ####
my $dir_map = read_map($ARGV[2]);
print $dir_map;
#my $top_dir = '.';
my $top_dir=$ARGV[1];

rename_dirs( $top_dir, $dir_map );

 sub rename_dirs {
 #print "process started for renaming directories";
    my ( $top_dir, $dir_map ) = @_;

    opendir (my $dh, $top_dir) or die "Can't open $top_dir: $!";
    my $save_dir = getcwd();
    chdir $top_dir;
    while (my $dir = readdir $dh) {
        next if ($dir eq '.') or ($dir eq '..'); 
        if ( exists $dir_map->{$dir} ) {
            my $new_name = $dir_map->{$dir};
            #say "$save_dir: rename $dir $new_name";
            File::Copy::move( $dir, $new_name )
                or die "Could not rename '$dir' as '$new_name': $!";
            $dir = $new_name;
        }
        rename_dirs( $dir, $dir_map ) if -d $dir;

    }
    chdir $save_dir;

}
##SUB ROUTINE TO READ THE TEXT FILE FROM COMMAND LINE ARGUMENTS##
sub read_map {
#print "read the text file \n";
    my ( $fn ) = @_;

    my %dir_map;

    open( my $fh, '<', $ARGV[2] ) or die "Could not open file '$fn': $!";
    while( my $line = <$fh> ) {
        chomp $line;
        my @fields = split /:/, $line;
        if ( @fields == 3 ) {
            $dir_map{$fields[2]} = $fields[1];
        }
    }
    close $fh;
    return \%dir_map;
}