#!/usr/bin/env python
"""
Rewrite Script. Sean B. Palmer, inamidst.com
Turns out to be equivalent to: 

$ cat .htaccess 
RewriteEngine on
RewriteBase /uri

RewriteRule ^([^/]+)\.([^\./]+)$ files/$2/$1.$2

RewriteCond %{DOCUMENT_ROOT}uri/files/$1 -d
RewriteRule ^([^\./]+)$ $1/ [L,R]

RewriteCond %{DOCUMENT_ROOT}uri/files/sans/$1 -f
RewriteRule ^([^\./]+)$ files/sans/$1 [L]

RewriteCond %{DOCUMENT_ROOT}uri/files/cgi/$1.cgi -f
RewriteRule ^([^\./]+)$ files/cgi/$1.cgi [L]

RewriteCond %{DOCUMENT_ROOT}uri/files/html/$1.html -f
RewriteRule ^([^\./]+)$ files/html/$1.html [L]

RewriteCond %{DOCUMENT_ROOT}uri/files/jpg/$1.jpg -f
RewriteRule ^([^\./]+)$ files/jpg/$1.jpg [L]

RewriteCond %{DOCUMENT_ROOT}uri/files/png/$1.png -f
RewriteRule ^([^\./]+)$ files/png/$1.png [L]

RewriteCond %{DOCUMENT_ROOT}uri/files/php/$1.php -f
RewriteRule ^([^\./]+)$ files/php/$1.php [L]

RewriteCond %{DOCUMENT_ROOT}uri/files/txt/$1.txt -f
RewriteRule ^([^\./]+)$ files/txt/$1.txt [L]

$ find -type f -exec ls -al {} \; | grep -v .svn
-rw-r--r--  1 sbp None 846 Apr 23 12:32 ./.htaccess
-rw-r--r--  1 sbp None 7 Apr 23 10:50 ./files/html/blargh.html
-rw-r--r--  1 sbp None 4 Apr 23 10:50 ./files/html/hmm.html
-rw-r--r--  1 sbp None 10 Apr 23 10:50 ./files/html/something.html
-rw-r--r--  1 sbp None 5 Apr 23 10:51 ./files/py/test.py
-rw-r--r--  1 sbp None 4 Apr 23 10:50 ./files/txt/heh.txt
-rw-r--r--  1 sbp None 4 Apr 23 10:50 ./files/txt/hmm.txt
-rwxr-xr-x  1 sbp None 2095 Apr 23 14:57 ./rewrite.py
"""

import sys, os

def main(): 
   # This should be a path with no slashes...
   path = sys.stdin.read().rstrip('\n')
   filename = path.split('/').pop()

   if '.' in filename: 
      basename, extension = filename.rsplit('.', 1)
      if os.path.isdir('files/' + extension): 
         fn = 'files/' + extension + '/' + filename
         if os.path.isfile(fn): 
            sys.stdout.write(fn + '\n')
         else: sys.stdout.write('NULL')
      else: sys.stdout.write('NULL')
   else: 
      if os.path.isdir(filename): 
         sys.stdout.write(filename + '/\n')
      elif os.path.isfile('files/sans/' + filename): 
         sys.stdout.write('files/sans/' + filename + '\n')
      else: # @@ stripext
         stripable = frozenset(['cgi', 'html', 'jpg', 'png', 'php', 'txt'])
         for dirname in os.listdir('files'): 
            if dirname in stripable: 
               fn = 'files/' + dirname + '/' + filename + '.' + dirname
               if os.path.isfile(fn): 
                  sys.stdout.write(fn + '\n')
                  break
         else: sys.stdout.write('NULL')

if __name__=="__main__": 
   main()