Switch to python3

Shared/lib/python3.4/site-packages/stdnum/cz/dic.py

@@ -0,0 +1,101 @@
+# dic.py - functions for handling Czech VAT numbers
+# coding: utf-8
+#
+# Copyright (C) 2012, 2013 Arthur de Jong
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301 USA
+
+"""DIČ (Daňové identifikační číslo, Czech VAT number).
+
+The number is an 8, 9 or 10 digit code that includes a check digit and is
+used to uniquely identify taxpayers for VAT (DPH in Czech). The number can
+refer to legal entities (8 digit numbers), individuals with a RČ (the 9 or
+10 digit Czech birth number) or individuals without a RČ (9 digit numbers
+that begin with a 6).
+
+>>> compact('CZ 25123891')
+'25123891'
+>>> validate('25123891')  # legal entity
+'25123891'
+>>> validate('25123890')  # incorrect check digit
+Traceback (most recent call last):
+    ...
+InvalidChecksum: ...
+>>> validate('7103192745')  # RČ
+'7103192745'
+>>> validate('640903926')  # special case
+'640903926'
+"""
+
+from stdnum.cz import rc
+from stdnum.exceptions import *
+from stdnum.util import clean
+
+
+def compact(number):
+    """Convert the number to the minimal representation. This strips the
+    number of any valid separators and removes surrounding whitespace."""
+    number = clean(number, ' /').upper().strip()
+    if number.startswith('CZ'):
+        number = number[2:]
+    return number
+
+
+def calc_check_digit_legal(number):
+    """Calculate the check digit for 8 digit legal entities. The number
+    passed should not have the check digit included."""
+    check = (11 - sum((8 - i) * int(n) for i, n in enumerate(number))) % 11
+    return str((check or 1) % 10)
+
+
+def calc_check_digit_special(number):
+    """Calculate the check digit for special cases. The number passed
+    should not have the first and last digits included."""
+    check = (11 - sum((8 - i) * int(n) for i, n in enumerate(number))) % 11
+    return str(9 - check % 10)
+
+
+def validate(number):
+    """Checks to see if the number provided is a valid VAT number. This
+    checks the length, formatting and check digit."""
+    number = compact(number)
+    if not number.isdigit():
+        raise InvalidFormat()
+    if len(number) == 8:
+        # legal entities
+        if number.startswith('9'):
+            raise InvalidComponent()
+        if calc_check_digit_legal(number[:-1]) != number[-1]:
+            raise InvalidChecksum()
+    elif len(number) == 9 and number.startswith('6'):
+        # special cases (skip first digit in calculation)
+        if calc_check_digit_special(number[1:-1]) != number[-1]:
+            raise InvalidChecksum()
+    elif len(number) in (9, 10):
+        # 9 or 10 digit individual
+        rc.validate(number)
+    else:
+        raise InvalidLength()
+    return number
+
+
+def is_valid(number):
+    """Checks to see if the number provided is a valid VAT number. This
+    checks the length, formatting and check digit."""
+    try:
+        return bool(validate(number))
+    except ValidationError:
+        return False