import image procurement code into project

udib/userinput.py

@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+
+""" This module is responsible for (interactive) user input handling. """
+
+import re
+
+from printmsg import pinput
+
+def prompt_yes_or_no(question, ask_until_valid = False):
+    """ Prompts the user with the specified yes/no question.
+
+        If 'ask_until_valid' is True, keeps repeating the prompt until the user
+        provides recognizable input to answer the question.
+
+    Parameters
+    ----------
+    question : str
+        The question to ask the user while prompting. The string is suffixed
+        with " (Yes/No) ".
+    ask_until_valid : bool
+        If this is set to True and the user provides an ambiguous answer, keeps
+        prompting indefinitely until an unambiguous answer is read.
+
+    Returns
+    -------
+    True : bool
+        If the user has answered 'yes'.
+    False : bool
+        If the user has answered 'no'.
+    None : None
+        If 'ask_until_valid' is False and the user has provided an ambiguous
+        response to the prompt.
+    """
+    user_input_is_valid = False
+
+    regex_yes = re.compile(r"^(y)$|^(Y)$|^(YES)$|^(Yes)$|^(yes)$")
+    regex_no  = re.compile(r"^(n)$|^(N)$|^(NO)$|^(No)$|^(no)$")
+
+    while(not user_input_is_valid):
+        user_input = pinput(f"{question} (Yes/No): ")
+
+        if (regex_yes.match(user_input)):
+            return True
+        elif (regex_no.match(user_input)):
+            return False
+        elif (not ask_until_valid):
+            return None
+