"""

Australian-specific Form helpers

"""

from django.forms import ValidationError

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

from django.forms.util import smart_unicode

from django.utils.translation import ugettext_lazy as _

import re

PHONE_DIGITS_RE = re.compile(r'^(\d{10})$')

class AUPostCodeField(RegexField):

    """Australian post code field."""

    default_error_messages = {

        'invalid': _('Enter a 4 digit post code.'),

    }

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

        super(AUPostCodeField, self).__init__(r'^\d{4}$',

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

class AUPhoneNumberField(Field):

    """Australian phone number field."""

    default_error_messages = {

        'invalid': u'Phone numbers must contain 10 digits.',

    }

    def clean(self, value):

        """

        Validate a phone number. Strips parentheses, whitespace and hyphens.

        """

        super(AUPhoneNumberField, self).clean(value)

        if value in EMPTY_VALUES:

            return u''

        value = re.sub('(\(|\)|\s+|-)', '', smart_unicode(value))

        phone_match = PHONE_DIGITS_RE.search(value)

        if phone_match:

            return u'%s' % phone_match.group(1)

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

class AUStateSelect(Select):

    """

    A Select widget that uses a list of Australian states/territories as its

    choices.

    """

    def __init__(self, attrs=None):

        from au_states import STATE_CHOICES

        super(AUStateSelect, self).__init__(attrs, choices=STATE_CHOICES)