1 files changed, 44 insertions, 0 deletions
diff --git a/webapp/django/contrib/localflavor/it/util.py b/webapp/django/contrib/localflavor/it/util.py
new file mode 100644
index 0000000000..c162ff7eff
--- /dev/null
+++ b/webapp/django/contrib/localflavor/it/util.py
@@ -0,0 +1,44 @@
+from django.utils.encoding import smart_str, smart_unicode
+
+def ssn_check_digit(value):
+    "Calculate Italian social security number check digit."
+    ssn_even_chars = {
+        '0': 0, '1': 1, '2': 2, '3': 3, '4': 4, '5': 5, '6': 6, '7': 7, '8': 8,
+        '9': 9, 'A': 0, 'B': 1, 'C': 2, 'D': 3, 'E': 4, 'F': 5, 'G': 6, 'H': 7,
+        'I': 8, 'J': 9, 'K': 10, 'L': 11, 'M': 12, 'N': 13, 'O': 14, 'P': 15,
+        'Q': 16, 'R': 17, 'S': 18, 'T': 19, 'U': 20, 'V': 21, 'W': 22, 'X': 23,
+        'Y': 24, 'Z': 25
+    }
+    ssn_odd_chars = {
+        '0': 1, '1': 0, '2': 5, '3': 7, '4': 9, '5': 13, '6': 15, '7': 17, '8':
+        19, '9': 21, 'A': 1, 'B': 0, 'C': 5, 'D': 7, 'E': 9, 'F': 13, 'G': 15,
+        'H': 17, 'I': 19, 'J': 21, 'K': 2, 'L': 4, 'M': 18, 'N': 20, 'O': 11,
+        'P': 3, 'Q': 6, 'R': 8, 'S': 12, 'T': 14, 'U': 16, 'V': 10, 'W': 22,
+        'X': 25, 'Y': 24, 'Z': 23
+    }
+    # Chars from 'A' to 'Z'
+    ssn_check_digits = [chr(x) for x in range(65, 91)]
+
+    ssn = value.upper()
+    total = 0
+    for i in range(0, 15):
+        try:
+            if i % 2 == 0:
+                total += ssn_odd_chars[ssn[i]]
+            else:
+                total += ssn_even_chars[ssn[i]]
+        except KeyError:
+            msg = "Character '%(char)s' is not allowed." % {'char': ssn[i]}
+            raise ValueError(msg)
+    return ssn_check_digits[total % 26]
+
+def vat_number_check_digit(vat_number):
+    "Calculate Italian VAT number check digit."
+    normalized_vat_number = smart_str(vat_number).zfill(10)
+    total = 0
+    for i in range(0, 10, 2):
+        total += int(normalized_vat_number[i])
+    for i in range(1, 11, 2):
+        quotient , remainder = divmod(int(normalized_vat_number[i]) * 2, 10)
+        total += quotient + remainder
+    return smart_unicode((10 - total % 10) % 10)