--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/localflavor/cl/forms.py	Fri Jul 18 18:22:23 2008 +0000
@@ -0,0 +1,94 @@
+"""
+Chile specific form helpers.
+"""
+
+from django.newforms import ValidationError
+from django.newforms.fields import RegexField, Select, EMPTY_VALUES
+from django.utils.translation import ugettext
+from django.utils.encoding import smart_unicode
+
+
+class CLRegionSelect(Select):
+    """
+    A Select widget that uses a list of Chilean Regions (Regiones)
+    as its choices.
+    """
+    def __init__(self, attrs=None):
+        from cl_regions import REGION_CHOICES
+        super(CLRegionSelect, self).__init__(attrs, choices=REGION_CHOICES)
+
+class CLRutField(RegexField):
+    """
+    Chilean "Rol Unico Tributario" (RUT) field. This is the Chilean national
+    identification number.
+
+    Samples for testing are available from
+    https://palena.sii.cl/cvc/dte/ee_empresas_emisoras.html
+    """
+    default_error_messages = {
+        'invalid': ugettext('Enter a valid Chilean RUT.'),
+        'strict': ugettext('Enter a valid Chilean RUT. The format is XX.XXX.XXX-X.'),
+        'checksum': ugettext('The Chilean RUT is not valid.'),
+    }
+
+    def __init__(self, *args, **kwargs):
+        if 'strict' in kwargs:
+            del kwargs['strict']
+            super(CLRutField, self).__init__(r'^(\d{1,2}\.)?\d{3}\.\d{3}-[\dkK]$',
+                error_message=self.default_error_messages['strict'], *args, **kwargs)
+        else:
+            # In non-strict mode, accept RUTs that validate but do not exist in
+            # the real world.
+            super(CLRutField, self).__init__(r'^[\d\.]{1,11}-?[\dkK]$', *args, **kwargs)
+
+    def clean(self, value):
+        """
+        Check and clean the Chilean RUT.
+        """
+        super(CLRutField, self).clean(value)
+        if value in EMPTY_VALUES:
+            return u''
+        rut, verificador = self._canonify(value)
+        if self._algorithm(rut) == verificador:
+            return self._format(rut, verificador)
+        else:
+            raise ValidationError(self.error_messages['checksum'])
+
+    def _algorithm(self, rut):
+        """
+        Takes RUT in pure canonical form, calculates the verifier digit.
+        """
+        suma  = 0
+        multi = 2
+        for r in rut[::-1]:
+            suma  += int(r) * multi
+            multi += 1
+            if multi == 8:
+                multi = 2
+        return u'0123456789K0'[11 - suma % 11]
+
+    def _canonify(self, rut):
+        """
+        Turns the RUT into one normalized format. Returns a (rut, verifier)
+        tuple.
+        """
+        rut = smart_unicode(rut).replace(' ', '').replace('.', '').replace('-', '')
+        return rut[:-1], rut[-1]
+
+    def _format(self, code, verifier=None):
+        """
+        Formats the RUT from canonical form to the common string representation.
+        If verifier=None, then the last digit in 'code' is the verifier.
+        """
+        if verifier is None:
+            verifier = code[-1]
+            code = code[:-1]
+        while len(code) > 3 and '.' not in code[:3]:
+            pos = code.find('.')
+            if pos == -1:
+                new_dot = -3
+            else:
+                new_dot = pos - 3
+            code = code[:new_dot] + '.' + code[new_dot:]
+        return u'%s-%s' % (code, verifier)
+