from django.utils.translation import gettext
from django.core import validators
from django.newforms import Field
from django.newforms.util import ValidationError
 
__all__ = (
    'FloatField',
)
 
EMPTY_VALUES = (None, '')
 
class FloatField(Field):
    def __init__(self, max_digits=None, decimal_places=None, *args, **kwargs):
        self.max_digits, self.decimal_places = max_digits, decimal_places
        super(FloatField, self).__init__(*args, **kwargs)
 
    def clean(self, value):
        """
        Validates that float() can be called on the input. Returns the result
        of float(). Returns None for empty values.
        """
        super(FloatField, self).clean(value)
        if value in EMPTY_VALUES:
            return None
 
        try:
            value = float(value)
        except (ValueError, TypeError):
            raise ValidationError(gettext(u'Enter a float number.'))
        v = validators.IsValidFloat(self.max_digits, self.decimal_places)
        try:
            v(value, None)
        except validators.ValidationError, e:
            raise ValidationError(gettext(u'Enter a float number.'))
        return value