use String::ShellQuote
use Cwd;

unless ($ARGV[0]) 
{
    $dir = getcwd;
}
else
{
    $dir = $ARGV[0]; 
}    

unless ($dir =~ /[\/]$/) { $dir .= "/"; }

opendir (DIR, $dir) or die $!;

my @arquivos = grep /\.mp3$/i, readdir DIR;

foreach my $mp3file (@arquivos)
{
    $new_name = $mp3file;
    $new_name =~ s/\s+/_/g; 
    $new_name =~ s/_-_/-/g; 
    $new_name =~ s/^[-_]+//;
    $new_name =~ s/&/and/g; #  & becomes "and"
    $new_name =~ s/[\(\)\[\]]+/_/g; # () and [] become _
    $new_name =~ s/,/_/g;
    $new_name =~ s/[\'\"]+/_/g; # no quotes
    $new_name =~ s/\`+/_/g; 
    $new_name =~ s/_+/_/g;  
    $new_name =~ s/-+/-/g; 

    $new_name = lc $new_name; # lowercase

    if ($new_name ne $mp3file)
    {
    $dir = shell_quote ($dir);
    $mp3file = shell_quote ($mp3file);
    $new_name = shell_quote ($new_name);
    system "mv $dir$mp3file $dir$new_name";
    print "\n$mp3file became $new_name";
    }    
}

closedir DIR;
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