from data import model

class DatabaseUsers(object):
  @property
  def federated_service(self):
    return None

  @property
  def supports_fresh_login(self):
    return True

  def ping(self):
    """ Always assumed to be working. If the DB is broken, other checks will handle it. """
    return (True, None)

  @property
  def supports_encrypted_credentials(self):
    return True

  def has_password_set(self, username):
    user = model.user.get_user(username)
    return user and user.password_hash is not None

  @property
  def requires_distinct_cli_password(self):
    # Since the database stores its own password.
    return True

  def verify_credentials(self, username_or_email, password):
    """ Simply delegate to the model implementation. """
    result = model.user.verify_user(username_or_email, password)
    if not result:
      return (None, 'Invalid Username or Password')

    return (result, None)

  def verify_and_link_user(self, username_or_email, password):
    """ Simply delegate to the model implementation. """
    return self.verify_credentials(username_or_email, password)

  def confirm_existing_user(self, username, password):
    return self.verify_credentials(username, password)

  def link_user(self, username_or_email):
    """ Never used since all users being added are already, by definition, in the database. """
    return (None, 'Unsupported for this authentication system')

  def get_and_link_federated_user_info(self, user_info, internal_create=False):
    """ Never used since all users being added are already, by definition, in the database. """
    return (None, 'Unsupported for this authentication system')

  def query_users(self, query, limit):
    """ No need to implement, as we already query for users directly in the database. """
    return (None, '', '')

  def check_group_lookup_args(self, group_lookup_args):
    """ Never used since all groups, by definition, are in the database. """
    return (False, 'Not supported')

  def iterate_group_members(self, group_lookup_args, page_size=None, disable_pagination=False):
    """ Never used since all groups, by definition, are in the database. """
    return (None, 'Not supported')

  def service_metadata(self):
    """ Never used since database has no metadata """
    return {}