use strict;
use warnings;
use Data::Dumper;

my $hash = {
    'x   ' => {
        'x   ' => '   dddd',
        'y   ' => 'dsds   '
    },
    'y   ' => [
        'dsfds     ',
        '   dsf',
    ],
    '   z' => 'dsfds'
};

trimHash($hash);
print Dumper($hash);

sub trimHash {
    my $h = $_[0];
    my ($k1, $k2);
    
    for $k1 (keys %$h) {
        if (ref $h->{$k1} eq 'HASH') {
            trimHash($h->{$k1});
        }
        elsif (ref $h->{$k1} eq 'ARRAY') {
            trimArray($h->{$k1});
        }
        else {
            $h->{$k1} = trim($h->{$k1});
        }
        $k2 = trim($k1);
        if ($k2 ne $k1) {
            $h->{$k2} = $h->{$k1};
            delete $h->{$k1};
        }
    }
}

sub trimArray {
    for (@{$_[0]}) {
        if (ref $_ eq 'HASH') {
            trimHash($_);
        }
        elsif (ref $_ eq 'ARRAY') {
            trimArray($_);
        }
        else {
            $_ = trim($_);
        }
    }
}

sub trim {
    my $s = $_[0];
    $s =~ s/\s\s+/ /g;
    $s =~ s/^ | $//g;
    return $s;
}