#!/usr/bin/perl

use Getopt::Std;
use Cwd;

getopt('sd');
$dirdelimiter = '/';
$dest = $opt_d ? $opt_d : Cwd::cwd();
$src = $opt_s ? $opt_s : Cwd::cwd();
if(substr($src,-1) ne $dirdelimiter) { $src .= $dirdelimiter; }
if(substr($dest,-1) ne $dirdelimiter) { $dest .= $dirdelimiter; }

if ($dest eq $src) {
    print "\n Move files from source directory to destination directory,"
    ."\n  rename them if file with same name already exists in destination directory."
    ."\n Usage: $0 [-s source_directory/] [-d destination_directory/]"
    ."\n If -s(ource) or -d(estination) is omitted, current directory is expected to be default for them."
    ."\n  Problem right now is, that -s(ource) and -d(estination) are the same:\n   "
    .$src."\n\n";
    exit;
}

%files = qw();
opendir (DIR, $dest) or die $!;
while ($file = readdir(DIR)) { if($file =~/[^.]/) { $files{$file} = 0; } }
closedir(DIR);

opendir (DIR, $src) or die $!;
while ($file = readdir(DIR)) {
    if($file =~/^[.]+$/) { next; }
    $test = $file;
    while(exists $files{$test}) {
        %c = get_props($test);
        $files{$test} = %c;
        $c{no}++;
        $test = $c{body}.$c{no}.$c{ext};
    }
    $files{$test} = 1;
    $command = "mv ".$src.$file." ".$dest.$test;
    print "$command\n";
    system($command);
}
closedir(DIR);
#use Data::Dumper; print Dumper(%files);

sub get_props {
    $x = $_[0];
    %y = qw();
    @xt = split(/\./,$x);
    if(scalar(@xt) < 2) { $y{ext} = ''; } else { $y{ext} = '.'.pop(@xt); }
    $withoutext = join('.',@xt);
    @withoutexta = split(/_/,$withoutext);
    if(scalar(@withoutexta) < 2 || @withoutexta[$#withoutexta] =~/[^\d]/) {
        $y{no} = 0;
        $y{body} = $withoutext.'_';
    } else {
        $y{no} = 0 + pop(@withoutexta);
        $y{body} = join('_',@withoutexta).'_';
    }
    return %y;
}