Mass renaming directories to move the year from end to beginning

Assuming you have access to perl rename (generally available in Ubuntu - thanks to @Serg for clarifying the difference. If in doubt, call /usr/bin/rename and you should get the right one), you could use:

rename -n 's/(.*) - (\d{4})\//$2 - $1/' */

Remove -n after testing to actually rename the directories. This assumes all the albums date between 1000 and 9999. Probably reasonable...

Explanation

• s/old/new replace old with new
• (.*) save any number of any characters to reference as $1 later
• (\d{4})\/ save four digits at the end of the line to reference as $2 later.
• */ match all directories (not files - thanks to @muru for help!)

Simple Python script can do such job:

$ tree
.
├── Aes Dana - Memory Shell - 2004
├── Anja Schneider & GummiHz - Back To Back (Remixes Part 2) - 2009
└── rename_dirs.py

2 directories, 1 file
$ ./rename_dirs.py */
$ tree
.
├── 2004 - Aes Dana  -  Memory Shell 
├── 2009 - Anja Schneider & GummiHz  -  Back To Back (Remixes Part 2) 
└── rename_dirs.py

Script contents:

#!/usr/bin/env python
from shutil import move;
import sys

for i in sys.argv[1:] :
    parts = i[:-1].split('-')
    year = parts[-1].strip()
    new_name = year + " - " + " - ".join(parts[:-1]).strip()
    move(i,new_name)

How this works:

• The main trick is that we execute script from the same directory where targets reside. We also pass */ to provide only directories as arguments to the script
• The script iterates over all command-line arguments, breaking down each filename into list of strings at - character. New filename is constructed out of parts we extracted.
• move() function from shutils module is what actually renames the directories

Note the usage: ./rename_dirs.py */