class AccountBaseUserModel(AccountModel):
    """
    A base for user models which need a username, an email, a password and
    related password checking and setting functionality for login purposes.
    """
    # TODO: Decide whether to remove ``username`` from the equation, entirely
    username = models.CharField(
        _(u'username'), max_length=30, validators=[ensure_not_email])
    email = models.EmailField(_(u'email'))
    password = fields.PasswordField(_(u'password'))
    first_name = models.CharField(_(u'first name'), max_length=255, blank=True)
    last_name = models.CharField(_(u'last name'), max_length=255, blank=True)
    primary_phone = models.CharField(
        _(u'primary phone'), max_length=20, blank=True)
    is_active = models.BooleanField(_(u'is active'), default=True)

    objects = AccountBaseUserManager()

    class Meta(AccountModel.Meta):
        abstract = True
        unique_together = (('account', 'username'), ('account', 'email'))
        ordering = ('username',)


    def __unicode__(self):
        return u'{0} for {1}'.format(self.username, self.account)

    def check_password(self, raw_password):
        """
        Returns ``True``, if the the hashed value of ``raw_password`` matches
        the value of ``self.password``, else returns ``False``.
        """
        return get_hash(raw_password) == self.password

    def is_authenticated(self):
        """
        Returns True, if the user can authenticate.
        """
        return self.can_authenticate()

    def can_authenticate(self):
        """
        Returns ``True``, if the user is active, else returns ``False``.
        """
        return self.is_active

    def has_account_access(self, account):
        """
        Returns ``True``, if ``self.account`` matches the provided ``account``,
        else returns ``False``.
        """
        if self.can_authenticate():
            return self.account_id == account.pk
        return False

    def set_password(self, raw_password):
        """
        Sets ``self.password`` to the hashed value of ``raw_password``.
        """
        self.password = get_hash(raw_password)
        self.save()


class AnonAccountUser(object):
    """
    Provides a similar API to ``AccountBaseUserModel`` unauthenticated users.
    """
    def __init__(self):
        self.username = u'Anonymous'

    def is_authenticated(self):
        """
        Always returns False.
        """
        return False