diff --git a/bin/prefix-date b/bin/prefix-date
index 723ca6e..e6fc0c5 100755
--- a/bin/prefix-date
+++ b/bin/prefix-date
@@ -1,19 +1,104 @@
-#!/usr/bin/env bash
-
-function datemv {
-    if [[ $(basename "$1") == $(stat -c "%y" "$1" | cut -d " " -f1)* ]]; then
-        echo "Do nothing with '$1'"
-    else
-        mv -v "$1" "$(dirname "$1")/$(stat -c "%y" "$1" | cut -d " " -f1)_$(basename "$1")"
-    fi
-}
-
-if [ -d $1 ]; then
-    for file in $(find "$1" -type f | grep -vP "\/\d{4}-\d{2}-\d{2}"); do
-        datemv "$file"
-    done
-else
-    echo "Directory not found '$1'"
-    exit
-fi
+#!/usr/bin/env python
+
+from __future__ import unicode_literals, division, absolute_import, with_statement, print_function
+
+import os
+import re
+
+from datetime import datetime
+from optparse import OptionParser
+from os import path
+
+def add(arr):
+    return arr[0] + arr[1]
+assert add([1, 2]) == 3
+
+def mul(arr):
+    return arr[0] * arr[1]
+assert mul([2, 3]) == 6
+
+def echo(arg):
+    print(arg)
+    return arg
+
+def compose(*funcs):
+    return lambda arg = None: reduce(lambda val, func: func(val), funcs, arg)
+
+test_compose = compose(lambda _: [2, 3], mul, lambda x: [x, 3], mul, lambda x: [x, 1], add)
+# 2 * 3 = 6 * 3 = 18 + 1 = 19
+assert test_compose() == 19
+
+date_reg_ex = re.compile("\d{4}-\d{2}-\d{2}_")
+doesnt_start_with_date = lambda string: date_reg_ex.search(string, 0, 11) is None
+assert doesnt_start_with_date("1234-56-78_") == False
+assert doesnt_start_with_date("a1234-56-78_")
+assert doesnt_start_with_date("1234-56-78")
+assert doesnt_start_with_date("1234-56-78_ sdfsakdsdf fjalsdjhfaskj  ldfh") == False
+
+def prop(key):
+    def obj(dic):
+        return dic[key]
+    return obj
+assert prop('key')({'key': 1}) == 1
+
+def path_join(directory):
+    def do_join(file_name):
+        return path.join(directory, file_name)
+    return do_join
+
+def mk_dir_map(ret, directory):
+    is_file = compose(path_join(directory), path.isfile)
+    files = filter(is_file, os.listdir(directory))
+    not_with_date = filter(doesnt_start_with_date, files)
+    ret[directory] = map(lambda x: {'original': x}, not_with_date)
+    return ret
+
+def add_date(ret, directory):
+    original = prop('original')
+    add_dir_name = path_join(directory)
+    def list_date(file_obj):
+        date_from_obj = compose(
+            original,
+            add_dir_name,
+            path.getctime,
+            datetime.fromtimestamp
+        )
+        date = date_from_obj(file_obj)
+        file_obj['new'] = date.strftime('%Y-%m-%d_{0}'.format(original(file_obj)))
+        return file_obj
+
+    ret[directory] = map(list_date, ret[directory])
+    return ret
+
+def rename(ret, directory):
+    original = compose(
+        prop('original'),
+        path_join(directory),
+    )
+    new = compose(
+        prop('new'),
+        path_join(directory),
+    )
+    def do_rename(file_obj):
+        os.rename(original(file_obj), new(file_obj))
+        return echo("mv -v {0} {1}".format(original(file_obj), new(file_obj)))
+    map(do_rename, ret[directory])
+    return ret
+
+def main(options, directories):
+    real_directories = filter(path.isdir, directories)
+    file_tree = reduce(mk_dir_map, real_directories, {})
+    file_tree = reduce(add_date, file_tree, file_tree)
+    file_tree = reduce(rename, file_tree, file_tree)
+
+if __name__ == '__main__':
+    parser = OptionParser()
+    parser.add_option("-f", "--file", dest="filename",
+                              help="write report to FILE", metavar="FILE")
+    parser.add_option("-q", "--quiet",
+                              action="store_false", dest="verbose", default=True,
+                                                help="don't print status messages to stdout")
+
+    (options, args) = parser.parse_args()
+    main(options, args)