--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/localflavor/no/forms.py	Fri Jul 18 18:22:23 2008 +0000
@@ -0,0 +1,81 @@
+"""
+Norwegian-specific Form helpers
+"""
+
+import re, datetime
+from django.newforms import ValidationError
+from django.newforms.fields import Field, RegexField, Select, EMPTY_VALUES
+from django.utils.translation import ugettext
+
+class NOZipCodeField(RegexField):
+    default_error_messages = {
+        'invalid': ugettext('Enter a zip code in the format XXXX.'),
+    }
+
+    def __init__(self, *args, **kwargs):
+        super(NOZipCodeField, self).__init__(r'^\d{4}$',
+            max_length=None, min_length=None, *args, **kwargs)
+
+class NOMunicipalitySelect(Select):
+    """
+    A Select widget that uses a list of Norwegian municipalities (fylker)
+    as its choices.
+    """
+    def __init__(self, attrs=None):
+        from no_municipalities import MUNICIPALITY_CHOICES
+        super(NOMunicipalitySelect, self).__init__(attrs, choices=MUNICIPALITY_CHOICES)
+
+class NOSocialSecurityNumber(Field):
+    """
+    Algorithm is documented at http://no.wikipedia.org/wiki/Personnummer
+    """
+    default_error_messages = {
+        'invalid': ugettext(u'Enter a valid Norwegian social security number.'),
+    }
+
+    def clean(self, value):
+        super(NOSocialSecurityNumber, self).clean(value)
+        if value in EMPTY_VALUES:
+            return u''
+
+        if not re.match(r'^\d{11}$', value):
+            raise ValidationError(self.error_messages['invalid'])
+
+        day = int(value[:2])
+        month = int(value[2:4])
+        year2 = int(value[4:6])
+
+        inum = int(value[6:9])
+        self.birthday = None
+        try:
+            if 000 <= inum < 500:
+                self.birthday = datetime.date(1900+year2, month, day)
+            if 500 <= inum < 750 and year2 > 54:
+                self.birthday = datetime.date(1800+year2, month, day)
+            if 500 <= inum < 1000 and year2 < 40:
+                self.birthday = datetime.date(2000+year2, month, day)
+            if 900 <= inum < 1000 and year2 > 39:
+                self.birthday = datetime.date(1900+year2, month, day)
+        except ValueError:
+            raise ValidationError(self.error_messages['invalid'])
+
+        sexnum = int(value[8])
+        if sexnum % 2 == 0:
+            self.gender = 'F'
+        else:
+            self.gender = 'M'
+
+        digits = map(int, list(value))
+        weight_1 = [3, 7, 6, 1, 8, 9, 4, 5, 2, 1, 0]
+        weight_2 = [5, 4, 3, 2, 7, 6, 5, 4, 3, 2, 1]
+
+        def multiply_reduce(aval, bval):
+            return sum([(a * b) for (a, b) in zip(aval, bval)])
+
+        if multiply_reduce(digits, weight_1) % 11 != 0:
+            raise ValidationError(self.error_messages['invalid'])
+        if multiply_reduce(digits, weight_2) % 11 != 0:
+            raise ValidationError(self.error_messages['invalid'])
+
+        return value
+