index folder for easier shell operation

flit.py

@@ -99,9 +99,23 @@ def random_char():
 
 
 def random_name():
-    chars = [random_char() for x in range(6)]
+    while True:
-    chars.insert(3, '-')
+        existing_names = get_folder_names()
-    return ''.join(chars)
+        index = 0
+        for existing in existing_names:
+            try:
+                e_index = int(existing[0:3])
+                index = max(e_index + 1, index)
+            except:
+                pass
+        name = "{:03d}-{}-{}".format(
+             index,
+             "".join([random_char() for x in range(3)]),
+             "".join([random_char() for x in range(3)])
+        )
+        if not os.path.exists(name):
+            break
+    return name
 
 
 def create_new(p, days, description):
@@ -210,8 +224,6 @@ if __name__ == '__main__':
     os.chdir(os.path.dirname(__file__))
     if opts.command == 'add':
         new_name = random_name()
-        while os.path.exists(new_name):
-            new_name = random_name()
         create_new(new_name, opts.days, opts.description)
         print(os.path.abspath(new_name))
         print("")