1 """

     2 Czech-specific form helpers

     3 """

     4 

     5 from django.forms import ValidationError

     6 from django.forms.fields import Select, RegexField, Field, EMPTY_VALUES

     7 from django.utils.translation import ugettext_lazy as _

     8 import re

     9 

    10 birth_number = re.compile(r'^(?P<birth>\d{6})/?(?P<id>\d{3,4})$')

    11 ic_number = re.compile(r'^(?P<number>\d{7})(?P<check>\d)$')

    12 

    13 class CZRegionSelect(Select):

    14     """

    15     A select widget widget with list of Czech regions as choices.

    16     """

    17     def __init__(self, attrs=None):

    18         from cz_regions import REGION_CHOICES

    19         super(CZRegionSelect, self).__init__(attrs, choices=REGION_CHOICES)

    20 

    21 class CZPostalCodeField(RegexField):

    22     """

    23     A form field that validates its input as Czech postal code.

    24     Valid form is XXXXX or XXX XX, where X represents integer.

    25     """

    26     default_error_messages = {

    27         'invalid': _(u'Enter a postal code in the format XXXXX or XXX XX.'),

    28     }

    29 

    30     def __init__(self, *args, **kwargs):

    31         super(CZPostalCodeField, self).__init__(r'^\d{5}$|^\d{3} \d{2}$',

    32             max_length=None, min_length=None, *args, **kwargs)

    33 

    34     def clean(self, value):

    35         """

    36         Validates the input and returns a string that contains only numbers.

    37         Returns an empty string for empty values.

    38         """

    39         v = super(CZPostalCodeField, self).clean(value)

    40         return v.replace(' ', '')

    41 

    42 class CZBirthNumberField(Field):

    43     """

    44     Czech birth number field.

    45     """

    46     default_error_messages = {

    47         'invalid_format': _(u'Enter a birth number in the format XXXXXX/XXXX or XXXXXXXXXX.'),

    48         'invalid_gender': _(u'Invalid optional parameter Gender, valid values are \'f\' and \'m\''),

    49         'invalid': _(u'Enter a valid birth number.'),

    50     }

    51 

    52     def clean(self, value, gender=None):

    53         super(CZBirthNumberField, self).__init__(value)

    54 

    55         if value in EMPTY_VALUES:

    56             return u''

    57 

    58         match = re.match(birth_number, value)

    59         if not match:

    60             raise ValidationError(self.error_messages['invalid_format'])

    61 

    62         birth, id = match.groupdict()['birth'], match.groupdict()['id']

    63 

    64         # Three digits for verificatin number were used until 1. january 1954

    65         if len(id) == 3:

    66             return u'%s' % value

    67 

    68         # Birth number is in format YYMMDD. Females have month value raised by 50.

    69         # In case that all possible number are already used (for given date),

    70         #  the month field is raised by 20.

    71         if gender is not None:

    72             if gender == 'f':

    73                 female_const = 50

    74             elif gender == 'm':

    75                 female_const = 0

    76             else:

    77                 raise ValidationError(self.error_messages['invalid_gender'])

    78 

    79             month = int(birth[2:4]) - female_const

    80             if (not 1 <= month <= 12):

    81                 if (not 1 <= (month - 20) <= 12):

    82                     raise ValidationError(self.error_messages['invalid'])

    83 

    84         day = int(birth[4:6])

    85         if not (1 <= day <= 31):

    86             raise ValidationError(self.error_messages['invalid'])

    87 

    88         # Fourth digit has been added since 1. January 1954.

    89         # It is modulo of dividing birth number and verification number by 11.

    90         # If the modulo were 10, the last number was 0 (and therefore, the whole

    91         # birth number wasn't divisable by 11. These number are no longer used (since 1985)

    92         # and the condition 'modulo == 10' can be removed in 2085.

    93 

    94         modulo = int(birth + id[:3]) % 11

    95 

    96         if (modulo == int(id[-1])) or (modulo == 10 and id[-1] == '0'):

    97             return u'%s' % value

    98         else:

    99             raise ValidationError(self.error_messages['invalid'])

   100 

   101 class CZICNumberField(Field):

   102     """

   103     Czech IC number field.

   104     """

   105     default_error_messages = {

   106         'invalid': _(u'Enter a valid IC number.'),

   107     }

   108 

   109     def clean(self, value):

   110         super(CZICNumberField, self).__init__(value)

   111 

   112         if value in EMPTY_VALUES:

   113             return u''

   114 

   115         match = re.match(ic_number, value)

   116         if not match:

   117             raise ValidationError(self.error_messages['invalid'])

   118 

   119         number, check = match.groupdict()['number'], int(match.groupdict()['check'])

   120 

   121         sum = 0

   122         weight = 8

   123         for digit in number:

   124             sum += int(digit)*weight

   125             weight -= 1

   126 

   127         remainder = sum % 11

   128 

   129         # remainder is equal:

   130         #  0 or 10: last digit is 1

   131         #  1: last digit is 0

   132         # in other case, last digin is 11 - remainder

   133 

   134         if (not remainder % 10 and check == 1) or \

   135         (remainder == 1 and check == 0) or \

   136         (check == (11 - remainder)):

   137             return u'%s' % value

   138 

   139         raise ValidationError(self.error_messages['invalid'])

   140