import datetime
from django import forms
from django.core import validators
from django.core.exceptions import ValidationError
from django.utils import six
from django.utils.encoding import force_text


class DateTimeNoTimeZoneField(forms.DateTimeField):
    def to_python(self, value):
        """
        Validates that the input can be converted to a datetime. Returns a
        Python datetime.datetime object.
        """
        if value in validators.EMPTY_VALUES:
            return None
        if isinstance(value, datetime.datetime):
            return value
        if isinstance(value, datetime.date):
            return datetime.datetime(value.year, value.month, value.day)
        if isinstance(value, list):
            # Input comes from a SplitDateTimeWidget, for example. So, it's two
            # components: date and time.
            if len(value) != 2:
                raise ValidationError(self.error_messages['invalid'])
            if value[0] in validators.EMPTY_VALUES and value[1] in validators.EMPTY_VALUES:
                return None
            value = '%s %s' % tuple(value)
                # Try to coerce the value to unicode.
        unicode_value = force_text(value, strings_only=True)
        if isinstance(unicode_value, six.text_type):
            value = unicode_value.strip()
        # If unicode, try to strptime against each input format.
        if isinstance(value, six.text_type):
            for format in self.input_formats:
                try:
                    return self.strptime(value, format)
                except (ValueError, TypeError):
                    continue
        raise ValidationError(self.error_messages['invalid'])