# Source code for evennia.accounts.accounts

    """
    Typeclass for Account objects.

    Note that this object is primarily intended to
    store OOC information, not game info! This
    object represents the actual user (not their
    character) and has NO actual presence in the
    game world (this is handled by the associated
    character object, so you should customize that
    instead for most things).

    """
    import re
    import time
    from random import getrandbits

    from django.conf import settings
    from django.contrib.auth import authenticate, password_validation
    from django.core.exceptions import ImproperlyConfigured, ValidationError
    from django.utils import timezone
    from django.utils.module_loading import import_string
    from django.utils.translation import gettext as _
    from evennia.accounts.manager import AccountManager
    from evennia.accounts.models import AccountDB
    from evennia.commands.cmdsethandler import CmdSetHandler
    from evennia.comms.models import ChannelDB
    from evennia.objects.models import ObjectDB
    from evennia.scripts.scripthandler import ScriptHandler
    from evennia.server.models import ServerConfig
    from evennia.server.signals import (
        SIGNAL_ACCOUNT_POST_CREATE,
        SIGNAL_OBJECT_POST_PUPPET,
        SIGNAL_OBJECT_POST_UNPUPPET,
    )
    from evennia.server.throttle import Throttle
    from evennia.typeclasses.attributes import ModelAttributeBackend, NickHandler
    from evennia.typeclasses.models import TypeclassBase
    from evennia.utils import class_from_module, create, logger
    from evennia.utils.optionhandler import OptionHandler
    from evennia.utils.utils import is_iter, lazy_property, make_iter, to_str, variable_from_module

    __all__ = ("DefaultAccount", "DefaultGuest")

    _SESSIONS = None

    _AT_SEARCH_RESULT = variable_from_module(*settings.SEARCH_AT_RESULT.rsplit(".", 1))
    _MULTISESSION_MODE = settings.MULTISESSION_MODE
    _AUTO_CREATE_CHARACTER_WITH_ACCOUNT = settings.AUTO_CREATE_CHARACTER_WITH_ACCOUNT
    _AUTO_PUPPET_ON_LOGIN = settings.AUTO_PUPPET_ON_LOGIN
    _MAX_NR_SIMULTANEOUS_PUPPETS = settings.MAX_NR_SIMULTANEOUS_PUPPETS
    _MAX_NR_CHARACTERS = settings.MAX_NR_CHARACTERS
    _CMDSET_ACCOUNT = settings.CMDSET_ACCOUNT
    _MUDINFO_CHANNEL = None
    _CONNECT_CHANNEL = None
    _CMDHANDLER = None

    # Create throttles for too many account-creations and login attempts
    CREATION_THROTTLE = Throttle(
        name="creation",
        limit=settings.CREATION_THROTTLE_LIMIT,
        timeout=settings.CREATION_THROTTLE_TIMEOUT,
    )
    LOGIN_THROTTLE = Throttle(
        name="login", limit=settings.LOGIN_THROTTLE_LIMIT, timeout=settings.LOGIN_THROTTLE_TIMEOUT
    )

    class AccountSessionHandler(object):
        """
        Manages the session(s) attached to an account.

        """

        def __init__(self, account):
            """
            Initializes the handler.

            Args:
                account (Account): The Account on which this handler is defined.

            """
            self.account = account

        def get(self, sessid=None):
            """
            Get the sessions linked to this object.

            Args:
                sessid (int, optional): Specify a given session by
                    session id.

            Returns:
                sessions (list): A list of Session objects. If `sessid`
                    is given, this is a list with one (or zero) elements.

            """
            global _SESSIONS
            if not _SESSIONS:
                from evennia.server.sessionhandler import SESSIONS as _SESSIONS
            if sessid:
                return make_iter(_SESSIONS.session_from_account(self.account, sessid))
            else:
                return _SESSIONS.sessions_from_account(self.account)

        def all(self):
            """
            Alias to get(), returning all sessions.

            Returns:
                sessions (list): All sessions.

            """
            return self.get()

        def count(self):
            """
            Get amount of sessions connected.

            Returns:
                sesslen (int): Number of sessions handled.

            """
            return len(self.get())

    class DefaultAccount(AccountDB, metaclass=TypeclassBase):
        """
        This is the base Typeclass for all Accounts. Accounts represent
        the person playing the game and tracks account info, password
        etc. They are OOC entities without presence in-game. An Account
        can connect to a Character Object in order to "enter" the
        game.

        Account Typeclass API:

        * Available properties (only available on initiated typeclass objects)

         - key (string) - name of account
         - name (string)- wrapper for user.username
         - aliases (list of strings) - aliases to the object. Will be saved to
                database as AliasDB entries but returned as strings.
         - dbref (int, read-only) - unique #id-number. Also "id" can be used.
         - date_created (string) - time stamp of object creation
         - permissions (list of strings) - list of permission strings
         - user (User, read-only) - django User authorization object
         - obj (Object) - game object controlled by account. 'character' can also
                         be used.
         - sessions (list of Sessions) - sessions connected to this account
         - is_superuser (bool, read-only) - if the connected user is a superuser

        * Handlers

         - locks - lock-handler: use locks.add() to add new lock strings
         - db - attribute-handler: store/retrieve database attributes on this
                                  self.db.myattr=val, val=self.db.myattr
         - ndb - non-persistent attribute handler: same as db but does not
                                      create a database entry when storing data
         - scripts - script-handler. Add new scripts to object with scripts.add()
         - cmdset - cmdset-handler. Use cmdset.add() to add new cmdsets to object
         - nicks - nick-handler. New nicks with nicks.add().

        * Helper methods

         - msg(text=None, from_obj=None, session=None, options=None, **kwargs)
         - execute_cmd(raw_string)
         - search(ostring, global_search=False, attribute_name=None,
                          use_nicks=False, location=None,
                          ignore_errors=False, account=False)
         - is_typeclass(typeclass, exact=False)
         - swap_typeclass(new_typeclass, clean_attributes=False, no_default=True)
         - access(accessing_obj, access_type='read', default=False, no_superuser_bypass=False)
         - check_permstring(permstring)

        * Hook methods

         basetype_setup()
         at_account_creation()

         > note that the following hooks are also found on Objects and are
           usually handled on the character level:

         - at_init()
         - at_access()
         - at_cmdset_get(**kwargs)
         - at_first_login()
         - at_post_login(session=None)
         - at_disconnect()
         - at_message_receive()
         - at_message_send()
         - at_server_reload()
         - at_server_shutdown()

        """

        objects = AccountManager()

        # properties
        @lazy_property
        def cmdset(self):
            return CmdSetHandler(self, True)

        @lazy_property
        def scripts(self):
            return ScriptHandler(self)

        @lazy_property
        def nicks(self):
            return NickHandler(self, ModelAttributeBackend)

        @lazy_property
        def sessions(self):
            return AccountSessionHandler(self)

        @lazy_property
        def options(self):
            return OptionHandler(
                self,
                options_dict=settings.OPTIONS_ACCOUNT_DEFAULT,
                savefunc=self.attributes.add,
                loadfunc=self.attributes.get,
                save_kwargs={"category": "option"},
                load_kwargs={"category": "option"},
            )

        # Do not make this a lazy property; the web UI will not refresh it!
        @property
        def characters(self):
            # Get playable characters list
            objs = self.db._playable_characters or []

            # Rebuild the list if legacy code left null values after deletion
            try:
                if None in objs:
                    objs = [x for x in self.db._playable_characters if x]
                    self.db._playable_characters = objs
            except Exception as e:
                logger.log_trace(e)
                logger.log_err(e)

            return objs

        def uses_screenreader(self, session=None):
            """
            Shortcut to determine if a session uses a screenreader. If no session given,
            will return true if any of the sessions use a screenreader.

            Args:
                session (Session, optional): The session to check for screen reader.

            """
            if session:
                return bool(session.protocol_flags.get("SCREENREADER", False))
            else:
                return any(
                    session.protocol_flags.get("SCREENREADER") for session in self.sessions.all()
                )

        def get_display_name(self, looker, **kwargs):
            """
            This is used by channels and other OOC communications methods to give a
            custom display of this account's input.

            Args:
                looker (Account): The one that will see this name.
                **kwargs: Unused by default, can be used to pass game-specific data.

            Returns:
                str: The name, possibly modified.

            """
            return f"|c{self.key}|n"

        # session-related methods

        def disconnect_session_from_account(self, session, reason=None):
            """
            Access method for disconnecting a given session from the
            account (connection happens automatically in the
            sessionhandler)

            Args:
                session (Session): Session to disconnect.
                reason (str, optional): Eventual reason for the disconnect.

            """
            global _SESSIONS
            if not _SESSIONS:
                from evennia.server.sessionhandler import SESSIONS as _SESSIONS
            _SESSIONS.disconnect(session, reason)

        # puppeting operations

        def puppet_object(self, session, obj):
            """
            Use the given session to control (puppet) the given object (usually
            a Character type).

            Args:
                session (Session): session to use for puppeting
                obj (Object): the object to start puppeting

            Raises:
                RuntimeError: If puppeting is not possible, the
                    `exception.msg` will contain the reason.

            """
            # safety checks
            if not obj:
                raise RuntimeError("Object not found")
            if not session:
                raise RuntimeError("Session not found")
            if self.get_puppet(session) == obj:
                # already puppeting this object
                self.msg("You are already puppeting this object.")
                return
            if not obj.access(self, "puppet"):
                # no access
                self.msg(f"You don't have permission to puppet '{obj.key}'.")
                return
            if obj.account:
                # object already puppeted
                if obj.account == self:
                    if obj.sessions.count():
                        # we may take over another of our sessions
                        # output messages to the affected sessions
                        if _MULTISESSION_MODE in (1, 3):
                            txt1 = f"Sharing |c{obj.name}|n with another of your sessions."
                            txt2 = f"|c{obj.name}|n|G is now shared from another of your sessions.|n"
                            self.msg(txt1, session=session)
                            self.msg(txt2, session=obj.sessions.all())
                        else:
                            txt1 = f"Taking over |c{obj.name}|n from another of your sessions."
                            txt2 = f"|c{obj.name}|n|R is now acted from another of your sessions.|n"
                            self.msg(txt1, session=session)
                            self.msg(txt2, session=obj.sessions.all())
                            self.unpuppet_object(obj.sessions.get())
                elif obj.account.is_connected:
                    # controlled by another account
                    self.msg(_("|c{key}|R is already puppeted by another Account.").format(key=obj.key))
                    return

            if session.puppet:
                # cleanly unpuppet eventual previous object puppeted by this session
                self.unpuppet_object(session)
            # if we get to this point the character is ready to puppet or it
            # was left with a lingering account/session reference from an unclean
            # server kill or similar

            # check so we are not puppeting too much already
            if _MAX_NR_SIMULTANEOUS_PUPPETS is not None:
                already_puppeted = self.get_all_puppets()
                if (
                    not self.is_superuser
                    and not self.check_permstring("Developer")
                    and obj not in already_puppeted
                    and len(self.get_all_puppets()) >= _MAX_NR_SIMULTANEOUS_PUPPETS
                ):
                    self.msg(
                        _(f"You cannot control any more puppets (max {_MAX_NR_SIMULTANEOUS_PUPPETS})")
                    )
                    return

            # do the puppeting
            obj.at_pre_puppet(self, session=session)

            # do the connection
            obj.sessions.add(session)
            obj.account = self
            session.puid = obj.id
            session.puppet = obj

            # re-cache locks to make sure superuser bypass is updated
            obj.locks.cache_lock_bypass(obj)
            # final hook
            obj.at_post_puppet()
            SIGNAL_OBJECT_POST_PUPPET.send(sender=obj, account=self, session=session)

        def unpuppet_object(self, session):
            """
            Disengage control over an object.

            Args:
                session (Session or list): The session or a list of
                    sessions to disengage from their puppets.

            Raises:
                RuntimeError With message about error.

            """
            for session in make_iter(session):
                obj = session.puppet
                if obj:
                    # do the disconnect, but only if we are the last session to puppet
                    obj.at_pre_unpuppet()
                    obj.sessions.remove(session)
                    if not obj.sessions.count():
                        del obj.account
                    obj.at_post_unpuppet(self, session=session)
                    SIGNAL_OBJECT_POST_UNPUPPET.send(sender=obj, session=session, account=self)
                # Just to be sure we're always clear.
                session.puppet = None
                session.puid = None

        def unpuppet_all(self):
            """
            Disconnect all puppets. This is called by server before a
            reset/shutdown.
            """
            self.unpuppet_object(self.sessions.all())

        def get_puppet(self, session):
            """
            Get an object puppeted by this session through this account. This is
            the main method for retrieving the puppeted object from the
            account's end.

            Args:
                session (Session): Find puppeted object based on this session

            Returns:
                puppet (Object): The matching puppeted object, if any.

            """
            return session.puppet if session else None

        def get_all_puppets(self):
            """
            Get all currently puppeted objects.

            Returns:
                puppets (list): All puppeted objects currently controlled
                    by this Account.

            """
            return list(set(session.puppet for session in self.sessions.all() if session.puppet))

        def __get_single_puppet(self):
            """
            This is a legacy convenience link for use with `MULTISESSION_MODE`.

            Returns:
                puppets (Object or list): Users of `MULTISESSION_MODE` 0 or 1 will
                    always get the first puppet back. Users of higher `MULTISESSION_MODE`s will
                    get a list of all puppeted objects.

            """
            puppets = self.get_all_puppets()
            if _MULTISESSION_MODE in (0, 1):
                return puppets and puppets[0] or None
            return puppets

        character = property(__get_single_puppet)
        puppet = property(__get_single_puppet)

        # utility methods
        @classmethod
        def is_banned(cls, **kwargs):
            """
            Checks if a given username or IP is banned.

            Keyword Args:
                ip (str, optional): IP address.
                username (str, optional): Username.

            Returns:
                is_banned (bool): Whether either is banned or not.

            """

            ip = kwargs.get("ip", "")
            if isinstance(ip, (tuple, list)):
                ip = ip[0]
            ip = ip.strip()
            username = kwargs.get("username", "").lower().strip()

            # Check IP and/or name bans
            bans = ServerConfig.objects.conf("server_bans")
            if bans and (
                any(tup[0] == username for tup in bans if username)
                or any(tup[2].match(ip) for tup in bans if ip and tup[2])
            ):
                return True

            return False

        @classmethod
        def get_username_validators(
            cls, validator_config=getattr(settings, "AUTH_USERNAME_VALIDATORS", [])
        ):
            """
            Retrieves and instantiates validators for usernames.

            Args:
                validator_config (list): List of dicts comprising the battery of
                    validators to apply to a username.

            Returns:
                validators (list): List of instantiated Validator objects.
            """

            objs = []
            for validator in validator_config:
                try:
                    klass = import_string(validator["NAME"])
                except ImportError:
                    msg = (
                        f"The module in NAME could not be imported: {validator['NAME']}. "
                        "Check your AUTH_USERNAME_VALIDATORS setting."
                    )
                    raise ImproperlyConfigured(msg)
                objs.append(klass(**validator.get("OPTIONS", {})))
            return objs

        @classmethod
        def authenticate(cls, username, password, ip="", **kwargs):
            """
            Checks the given username/password against the database to see if the
            credentials are valid.

            Note that this simply checks credentials and returns a valid reference
            to the user-- it does not log them in!

            To finish the job:
            After calling this from a Command, associate the account with a Session:
            - session.sessionhandler.login(session, account)

            ...or after calling this from a View, associate it with an HttpRequest:
            - django.contrib.auth.login(account, request)

            Args:
                username (str): Username of account
                password (str): Password of account
                ip (str, optional): IP address of client

            Keyword Args:
                session (Session, optional): Session requesting authentication

            Returns:
                account (DefaultAccount, None): Account whose credentials were
                    provided if not banned.
                errors (list): Error messages of any failures.

            """
            errors = []
            if ip:
                ip = str(ip)

            # See if authentication is currently being throttled
            if ip and LOGIN_THROTTLE.check(ip):
                errors.append(_("Too many login failures; please try again in a few minutes."))

                # With throttle active, do not log continued hits-- it is a
                # waste of storage and can be abused to make your logs harder to
                # read and/or fill up your disk.
                return None, errors

            # Check IP and/or name bans
            banned = cls.is_banned(username=username, ip=ip)
            if banned:
                # this is a banned IP or name!
                errors.append(
                    _(
                        "|rYou have been banned and cannot continue from here."
                        "\nIf you feel this ban is in error, please email an admin.|x"
                    )
                )
                logger.log_sec(f"Authentication Denied (Banned): {username} (IP: {ip}).")
                LOGIN_THROTTLE.update(ip, "Too many sightings of banned artifact.")
                return None, errors

            # Authenticate and get Account object
            account = authenticate(username=username, password=password)
            if not account:
                # User-facing message
                errors.append(_("Username and/or password is incorrect."))

                # Log auth failures while throttle is inactive
                logger.log_sec(f"Authentication Failure: {username} (IP: {ip}).")

                # Update throttle
                if ip:
                    LOGIN_THROTTLE.update(ip, _("Too many authentication failures."))

                # Try to call post-failure hook
                session = kwargs.get("session", None)
                if session:
                    account = AccountDB.objects.get_account_from_name(username)
                    if account:
                        account.at_failed_login(session)

                return None, errors

            # Account successfully authenticated
            logger.log_sec(f"Authentication Success: {account} (IP: {ip}).")
            return account, errors

        @classmethod
        def normalize_username(cls, username):
            """
            Django: Applies NFKC Unicode normalization to usernames so that visually
            identical characters with different Unicode code points are considered
            identical.

            (This deals with the Turkish "i" problem and similar
            annoyances. Only relevant if you go out of your way to allow Unicode
            usernames though-- Evennia accepts ASCII by default.)

            In this case we're simply piggybacking on this feature to apply
            additional normalization per Evennia's standards.
            """
            username = super(DefaultAccount, cls).normalize_username(username)

            # strip excessive spaces in accountname
            username = re.sub(r"\s+", " ", username).strip()

            return username

        @classmethod
        def validate_username(cls, username):
            """
            Checks the given username against the username validator associated with
            Account objects, and also checks the database to make sure it is unique.

            Args:
                username (str): Username to validate

            Returns:
                valid (bool): Whether or not the password passed validation
                errors (list): Error messages of any failures

            """
            valid = []
            errors = []

            # Make sure we're at least using the default validator
            validators = cls.get_username_validators()
            if not validators:
                validators = [cls.username_validator]

            # Try username against all enabled validators
            for validator in validators:
                try:
                    valid.append(not validator(username))
                except ValidationError as e:
                    valid.append(False)
                    errors.extend(e.messages)

            # Disqualify if any check failed
            if False in valid:
                valid = False
            else:
                valid = True

            return valid, errors

        @classmethod
        def validate_password(cls, password, account=None):
            """
            Checks the given password against the list of Django validators enabled
            in the server.conf file.

            Args:
                password (str): Password to validate

            Keyword Args:
                account (DefaultAccount, optional): Account object to validate the
                    password for. Optional, but Django includes some validators to
                    do things like making sure users aren't setting passwords to the
                    same value as their username. If left blank, these user-specific
                    checks are skipped.

            Returns:
                valid (bool): Whether or not the password passed validation
                error (ValidationError, None): Any validation error(s) raised. Multiple
                    errors can be nested within a single object.

            """
            valid = False
            error = None

            # Validation returns None on success; invert it and return a more sensible bool
            try:
                valid = not password_validation.validate_password(password, user=account)
            except ValidationError as e:
                error = e

            return valid, error

        def set_password(self, password, **kwargs):
            """
            Applies the given password to the account. Logs and triggers the `at_password_change` hook.

            Args:
                password (str): Password to set.

            Notes:
                This is called by Django also when logging in; it should not be mixed up with
                validation, since that would mean old passwords in the database (pre validation checks)
                could get invalidated.

            """
            super().set_password(password)
            logger.log_sec(f"Password successfully changed for {self}.")
            self.at_password_change()

        def create_character(self, *args, **kwargs):
            """
            Create a character linked to this account.

            Args:
                key (str, optional): If not given, use the same name as the account.
                typeclass (str, optional): Typeclass to use for this character. If
                    not given, use settings.BASE_CHARACTER_TYPECLASS.
                permissions (list, optional): If not given, use the account's permissions.
                ip (str, optional): The client IP creating this character. Will fall back to the
                    one stored for the account if not given.
                kwargs (any): Other kwargs will be used in the create_call.
            Returns:
                Object: A new character of the `character_typeclass` type. None on an error.
                list or None: A list of errors, or None.

            """
            # parse inputs
            character_key = kwargs.pop("key", self.key)
            character_ip = kwargs.pop("ip", self.db.creator_ip)
            character_permissions = kwargs.pop("permissions", self.permissions)

            # Load the appropriate Character class
            character_typeclass = kwargs.pop("typeclass", None)
            character_typeclass = (
                character_typeclass if character_typeclass else settings.BASE_CHARACTER_TYPECLASS
            )
            Character = class_from_module(character_typeclass)

            if "location" not in kwargs:
                kwargs["location"] = ObjectDB.objects.get_id(settings.START_LOCATION)

            # Create the character
            character, errs = Character.create(
                character_key,
                self,
                ip=character_ip,
                typeclass=character_typeclass,
                permissions=character_permissions,
                **kwargs,
            )
            if character:
                # Update playable character list
                if character not in self.characters:
                    self.db._playable_characters.append(character)

                # We need to set this to have @ic auto-connect to this character
                self.db._last_puppet = character
            return character, errs

        @classmethod
        def create(cls, *args, **kwargs):
            """
            Creates an Account (or Account/Character pair for MULTISESSION_MODE<2)
            with default (or overridden) permissions and having joined them to the
            appropriate default channels.

            Keyword Args:
                username (str): Username of Account owner
                password (str): Password of Account owner
                email (str, optional): Email address of Account owner
                ip (str, optional): IP address of requesting connection
                guest (bool, optional): Whether or not this is to be a Guest account

                permissions (str, optional): Default permissions for the Account
                typeclass (str, optional): Typeclass to use for new Account
                character_typeclass (str, optional): Typeclass to use for new char
                    when applicable.

            Returns:
                account (Account): Account if successfully created; None if not
                errors (list): List of error messages in string form

            """

            account = None
            errors = []

            username = kwargs.get("username")
            password = kwargs.get("password")
            email = kwargs.get("email", "").strip()
            guest = kwargs.get("guest", False)

            permissions = kwargs.get("permissions", settings.PERMISSION_ACCOUNT_DEFAULT)
            typeclass = kwargs.get("typeclass", cls)

            ip = kwargs.get("ip", "")
            if isinstance(ip, (tuple, list)):
                ip = ip[0]

            if ip and CREATION_THROTTLE.check(ip):
                errors.append(
                    _("You are creating too many accounts. Please log into an existing account.")
                )
                return None, errors

            # Normalize username
            username = cls.normalize_username(username)

            # Validate username
            if not guest:
                valid, errs = cls.validate_username(username)
                if not valid:
                    # this echoes the restrictions made by django's auth
                    # module (except not allowing spaces, for convenience of
                    # logging in).
                    errors.extend(errs)
                    return None, errors

            # Validate password
            # Have to create a dummy Account object to check username similarity
            valid, errs = cls.validate_password(password, account=cls(username=username))
            if not valid:
                errors.extend(errs)
                return None, errors

            # Check IP and/or name bans
            banned = cls.is_banned(username=username, ip=ip)
            if banned:
                # this is a banned IP or name!
                string = _(
                    "|rYou have been banned and cannot continue from here."
                    "\nIf you feel this ban is in error, please email an admin.|x"
                )
                errors.append(string)
                return None, errors

            # everything's ok. Create the new account.
            try:
                try:
                    account = create.create_account(
                        username, email, password, permissions=permissions, typeclass=typeclass
                    )
                    logger.log_sec(f"Account Created: {account} (IP: {ip}).")

                except Exception:
                    errors.append(
                        _(
                            "There was an error creating the Account. "
                            "If this problem persists, contact an admin."
                        )
                    )
                    logger.log_trace()
                    return None, errors

                # This needs to be set so the engine knows this account is
                # logging in for the first time. (so it knows to call the right
                # hooks during login later)
                account.db.FIRST_LOGIN = True

                # Record IP address of creation, if available
                if ip:
                    account.db.creator_ip = ip

                # join the new account to the public channel
                pchannel = ChannelDB.objects.get_channel(settings.DEFAULT_CHANNELS[0]["key"])
                if not pchannel or not pchannel.connect(account):
                    string = "New account '{account.key}' could not connect to public channel!"
                    errors.append(string)
                    logger.log_err(string)

                if account and _AUTO_CREATE_CHARACTER_WITH_ACCOUNT:
                    # Auto-create a character to go with this account

                    character, errs = account.create_character(
                        typeclass=kwargs.get("character_typeclass")
                    )
                    if errs:
                        errors.extend(errs)

            except Exception:
                # We are in the middle between logged in and -not, so we have
                # to handle tracebacks ourselves at this point. If we don't,
                # we won't see any errors at all.
                errors.append(_("An error occurred. Please e-mail an admin if the problem persists."))
                logger.log_trace()

            # Update the throttle to indicate a new account was created from this IP
            if ip and not guest:
                CREATION_THROTTLE.update(ip, "Too many accounts being created.")
            SIGNAL_ACCOUNT_POST_CREATE.send(sender=account, ip=ip)
            return account, errors

        def delete(self, *args, **kwargs):
            """
            Deletes the account persistently.

            Notes:
                `*args` and `**kwargs` are passed on to the base delete
                 mechanism (these are usually not used).

            Return:
                bool: If deletion was successful. Only time it fails would be
                    if the Account was already deleted. Note that even on a failure,
                    connected resources (nicks/aliases etc) will still have been
                    deleted.

            """
            for session in self.sessions.all():
                # unpuppeting all objects and disconnecting the user, if any
                # sessions remain (should usually be handled from the
                # deleting command)
                try:
                    self.unpuppet_object(session)
                except RuntimeError:
                    # no puppet to disconnect from
                    pass
                session.sessionhandler.disconnect(session, reason=_("Account being deleted."))
            self.scripts.stop()
            self.attributes.clear()
            self.nicks.clear()
            self.aliases.clear()
            if not self.pk:
                return False
            super().delete(*args, **kwargs)
            return True

        # methods inherited from database model

        def msg(self, text=None, from_obj=None, session=None, options=None, **kwargs):
            """
            Evennia -> User
            This is the main route for sending data back to the user from the
            server.

            Args:
                text (str or tuple, optional): The message to send. This
                    is treated internally like any send-command, so its
                    value can be a tuple if sending multiple arguments to
                    the `text` oob command.
                from_obj (Object or Account or list, optional): Object sending. If given, its
                    at_msg_send() hook will be called. If iterable, call on all entities.
                session (Session or list, optional): Session object or a list of
                    Sessions to receive this send. If given, overrules the
                    default send behavior for the current
                    MULTISESSION_MODE.
                options (list): Protocol-specific options. Passed on to the protocol.
            Keyword Args:
                any (dict): All other keywords are passed on to the protocol.

            """
            if from_obj:
                # call hook
                for obj in make_iter(from_obj):
                    try:
                        obj.at_msg_send(text=text, to_obj=self, **kwargs)
                    except Exception:
                        # this may not be assigned.
                        logger.log_trace()
            try:
                if not self.at_msg_receive(text=text, **kwargs):
                    # abort message to this account
                    return
            except Exception:
                # this may not be assigned.
                pass

            kwargs["options"] = options

            if text is not None:
                if not (isinstance(text, str) or isinstance(text, tuple)):
                    # sanitize text before sending across the wire
                    try:
                        text = to_str(text)
                    except Exception:
                        text = repr(text)
                kwargs["text"] = text

            # session relay
            sessions = make_iter(session) if session else self.sessions.all()
            for session in sessions:
                session.data_out(**kwargs)

        def execute_cmd(self, raw_string, session=None, **kwargs):
            """
            Do something as this account. This method is never called normally,
            but only when the account object itself is supposed to execute the
            command. It takes account nicks into account, but not nicks of
            eventual puppets.

            Args:
                raw_string (str): Raw command input coming from the command line.
                session (Session, optional): The session to be responsible
                    for the command-send

            Keyword Args:
                kwargs (any): Other keyword arguments will be added to the
                    found command object instance as variables before it
                    executes. This is unused by default Evennia but may be
                    used to set flags and change operating parameters for
                    commands at run-time.

            """
            # break circular import issues
            global _CMDHANDLER
            if not _CMDHANDLER:
                from evennia.commands.cmdhandler import cmdhandler as _CMDHANDLER
            raw_string = self.nicks.nickreplace(
                raw_string, categories=("inputline", "channel"), include_account=False
            )
            if not session and _MULTISESSION_MODE in (0, 1):
                # for these modes we use the first/only session
                sessions = self.sessions.get()
                session = sessions[0] if sessions else None

            return _CMDHANDLER(self, raw_string, callertype="account", session=session, **kwargs)

        # channel receive hooks

        def at_pre_channel_msg(self, message, channel, senders=None, **kwargs):
            """
            Called by the Channel just before passing a message into `channel_msg`.
            This allows for tweak messages per-user and also to abort the
            receive on the receiver-level.

            Args:
                message (str): The message sent to the channel.
                channel (Channel): The sending channel.
                senders (list, optional): Accounts or Objects acting as senders.
                    For most normal messages, there is only a single sender. If
                    there are no senders, this may be a broadcasting message.
                **kwargs: These are additional keywords passed into `channel_msg`.
                    If `no_prefix=True` or `emit=True` are passed, the channel
                    prefix will not be added (`[channelname]: ` by default)

            Returns:
                str or None: Allows for customizing the message for this recipient.
                    If returning `None` (or `False`) message-receiving is aborted.
                    The returning string will be passed into `self.channel_msg`.

            Notes:
                This support posing/emotes by starting channel-send with : or ;.

            """
            if senders:
                sender_string = ", ".join(sender.get_display_name(self) for sender in senders)
                message_lstrip = message.lstrip()
                if message_lstrip.startswith((":", ";")):
                    # this is a pose, should show as e.g. "User1 smiles to channel"
                    spacing = "" if message_lstrip[1:].startswith((":", "'", ",")) else " "
                    message = f"{sender_string}{spacing}{message_lstrip[1:]}"
                else:
                    # normal message
                    message = f"{sender_string}: {message}"

            if not kwargs.get("no_prefix") or not kwargs.get("emit"):
                message = channel.channel_prefix() + message

            return message

        def channel_msg(self, message, channel, senders=None, **kwargs):
            """
            This performs the actions of receiving a message to an un-muted
            channel.

            Args:
                message (str): The message sent to the channel.
                channel (Channel): The sending channel.
                senders (list, optional): Accounts or Objects acting as senders.
                    For most normal messages, there is only a single sender. If
                    there are no senders, this may be a broadcasting message or
                    similar.
                **kwargs: These are additional keywords originally passed into
                    `Channel.msg`.

            Notes:
                Before this, `Channel.at_pre_channel_msg` will fire, which offers a way
                to customize the message for the receiver on the channel-level.

            """
            self.msg(
                text=(message, {"from_channel": channel.id}),
                from_obj=senders,
                options={"from_channel": channel.id},
            )

        def at_post_channel_msg(self, message, channel, senders=None, **kwargs):
            """
            Called by `self.channel_msg` after message was received.

            Args:
                message (str): The message sent to the channel.
                channel (Channel): The sending channel.
                senders (list, optional): Accounts or Objects acting as senders.
                    For most normal messages, there is only a single sender. If
                    there are no senders, this may be a broadcasting message.
                **kwargs: These are additional keywords passed into `channel_msg`.

            """
            pass

        # search method

        def search(
            self,
            searchdata,
            return_puppet=False,
            search_object=False,
            typeclass=None,
            nofound_string=None,
            multimatch_string=None,
            use_nicks=True,
            quiet=False,
            **kwargs,
        ):
            """
            This is similar to `DefaultObject.search` but defaults to searching
            for Accounts only.

            Args:
                searchdata (str or int): Search criterion, the Account's
                    key or dbref to search for.
                return_puppet (bool, optional): Instructs the method to
                    return matches as the object the Account controls rather
                    than the Account itself (or None) if nothing is puppeted).
                search_object (bool, optional): Search for Objects instead of
                    Accounts. This is used by e.g. the @examine command when
                    wanting to examine Objects while OOC.
                typeclass (Account typeclass, optional): Limit the search
                    only to this particular typeclass. This can be used to
                    limit to specific account typeclasses or to limit the search
                    to a particular Object typeclass if `search_object` is True.
                nofound_string (str, optional): A one-time error message
                    to echo if `searchdata` leads to no matches. If not given,
                    will fall back to the default handler.
                multimatch_string (str, optional): A one-time error
                    message to echo if `searchdata` leads to multiple matches.
                    If not given, will fall back to the default handler.
                use_nicks (bool, optional): Use account-level nick replacement.
                quiet (bool, optional): If set, will not show any error to the user,
                    and will also lead to returning a list of matches.

            Return:
                match (Account, Object or None): A single Account or Object match.
                list: If `quiet=True` this is a list of 0, 1 or more Account or Object matches.

            Notes:
                Extra keywords are ignored, but are allowed in call in
                order to make API more consistent with
                objects.objects.DefaultObject.search.

            """
            # handle me, self and *me, *self
            if isinstance(searchdata, str):
                # handle wrapping of common terms
                if searchdata.lower() in ("me", "*me", "self", "*self"):
                    return self
            searchdata = self.nicks.nickreplace(
                searchdata, categories=("account",), include_account=False
            )
            if search_object:
                matches = ObjectDB.objects.object_search(searchdata, typeclass=typeclass)
            else:
                matches = AccountDB.objects.account_search(searchdata, typeclass=typeclass)

            if quiet:
                matches = list(matches)
                if return_puppet:
                    matches = [match.puppet for match in matches]
            else:
                matches = _AT_SEARCH_RESULT(
                    matches,
                    self,
                    query=searchdata,
                    nofound_string=nofound_string,
                    multimatch_string=multimatch_string,
                )
                if matches and return_puppet:
                    try:
                        matches = matches.puppet
                    except AttributeError:
                        return None
            return matches

        def access(
            self, accessing_obj, access_type="read", default=False, no_superuser_bypass=False, **kwargs
        ):
            """
            Determines if another object has permission to access this
            object in whatever way.

            Args:
              accessing_obj (Object): Object trying to access this one.
              access_type (str, optional): Type of access sought.
              default (bool, optional): What to return if no lock of
                access_type was found
              no_superuser_bypass (bool, optional): Turn off superuser
                lock bypassing. Be careful with this one.

            Keyword Args:
              kwargs (any): Passed to the at_access hook along with the result.

            Returns:
                result (bool): Result of access check.

            """
            result = super().access(
                accessing_obj,
                access_type=access_type,
                default=default,
                no_superuser_bypass=no_superuser_bypass,
            )
            self.at_access(result, accessing_obj, access_type, **kwargs)
            return result

        @property
        def idle_time(self):
            """
            Returns the idle time of the least idle session in seconds. If
            no sessions are connected it returns nothing.
            """
            idle = [session.cmd_last_visible for session in self.sessions.all()]
            if idle:
                return time.time() - float(max(idle))
            return None

        @property
        def connection_time(self):
            """
            Returns the maximum connection time of all connected sessions
            in seconds. Returns nothing if there are no sessions.
            """
            conn = [session.conn_time for session in self.sessions.all()]
            if conn:
                return time.time() - float(min(conn))
            return None

        # account hooks

        def basetype_setup(self):
            """
            This sets up the basic properties for an account. Overload this
            with at_account_creation rather than changing this method.

            """
            # A basic security setup
            lockstring = (
                "examine:perm(Admin);edit:perm(Admin);"
                "delete:perm(Admin);boot:perm(Admin);msg:all();"
                "noidletimeout:perm(Builder) or perm(noidletimeout)"
            )
            self.locks.add(lockstring)

            # The ooc account cmdset
            self.cmdset.add_default(_CMDSET_ACCOUNT, persistent=True)

        def at_account_creation(self):
            """
            This is called once, the very first time the account is created
            (i.e. first time they register with the game). It's a good
            place to store attributes all accounts should have, like
            configuration values etc.

            """
            # set an (empty) attribute holding the characters this account has
            lockstring = "attrread:perm(Admins);attredit:perm(Admins);attrcreate:perm(Admins);"
            self.attributes.add("_playable_characters", [], lockstring=lockstring)
            self.attributes.add("_saved_protocol_flags", {}, lockstring=lockstring)

        def at_init(self):
            """
            This is always called whenever this object is initiated --
            that is, whenever it its typeclass is cached from memory. This
            happens on-demand first time the object is used or activated
            in some way after being created but also after each server
            restart or reload. In the case of account objects, this usually
            happens the moment the account logs in or reconnects after a
            reload.

            """
            pass

        # Note that the hooks below also exist in the character object's
        # typeclass. You can often ignore these and rely on the character
        # ones instead, unless you are implementing a multi-character game
        # and have some things that should be done regardless of which
        # character is currently connected to this account.

        def at_first_save(self):
            """
            This is a generic hook called by Evennia when this object is
            saved to the database the very first time.  You generally
            don't override this method but the hooks called by it.

            """
            self.basetype_setup()
            self.at_account_creation()
            # initialize Attribute/TagProperties
            self.init_evennia_properties()

            permissions = [settings.PERMISSION_ACCOUNT_DEFAULT]
            if hasattr(self, "_createdict"):
                # this will only be set if the utils.create_account
                # function was used to create the object.
                cdict = self._createdict
                updates = []
                if not cdict.get("key"):
                    if not self.db_key:
                        self.db_key = f"#{self.dbid}"
                        updates.append("db_key")
                elif self.key != cdict.get("key"):
                    updates.append("db_key")
                    self.db_key = cdict["key"]
                if updates:
                    self.save(update_fields=updates)

                if cdict.get("locks"):
                    self.locks.add(cdict["locks"])
                if cdict.get("permissions"):
                    permissions = cdict["permissions"]
                if cdict.get("tags"):
                    # this should be a list of tags, tuples (key, category) or (key, category, data)
                    self.tags.batch_add(*cdict["tags"])
                if cdict.get("attributes"):
                    # this should be tuples (key, val, ...)
                    self.attributes.batch_add(*cdict["attributes"])
                if cdict.get("nattributes"):
                    # this should be a dict of nattrname:value
                    for key, value in cdict["nattributes"]:
                        self.nattributes.add(key, value)
                del self._createdict

            self.permissions.batch_add(*permissions)

        def at_access(self, result, accessing_obj, access_type, **kwargs):
            """
            This is triggered after an access-call on this Account has
                completed.

            Args:
                result (bool): The result of the access check.
                accessing_obj (any): The object requesting the access
                    check.
                access_type (str): The type of access checked.

            Keyword Args:
                kwargs (any): These are passed on from the access check
                    and can be used to relay custom instructions from the
                    check mechanism.

            Notes:
                This method cannot affect the result of the lock check and
                its return value is not used in any way. It can be used
                e.g.  to customize error messages in a central location or
                create other effects based on the access result.

            """
            pass

        def at_cmdset_get(self, **kwargs):
            """
            Called just *before* cmdsets on this account are requested by
            the command handler. The cmdsets are available as
            `self.cmdset`. If changes need to be done on the fly to the
            cmdset before passing them on to the cmdhandler, this is the
            place to do it.  This is called also if the account currently
            have no cmdsets. kwargs are usually not used unless the
            cmdset is generated dynamically.

            """
            pass

        def at_first_login(self, **kwargs):
            """
            Called the very first time this account logs into the game.
            Note that this is called *before* at_pre_login, so no session
            is established and usually no character is yet assigned at
            this point. This hook is intended for account-specific setup
            like configurations.

            Args:
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            """
            pass

        def at_password_change(self, **kwargs):
            """
            Called after a successful password set/modify.

            Args:
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            """
            pass

        def at_pre_login(self, **kwargs):
            """
            Called every time the user logs in, just before the actual
            login-state is set.

            Args:
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            """
            pass

        def _send_to_connect_channel(self, message):
            """
            Helper method for loading and sending to the comm channel dedicated to
            connection messages. This will also be sent to the mudinfo channel.

            Args:
                message (str): A message to send to the connect channel.

            """
            global _MUDINFO_CHANNEL, _CONNECT_CHANNEL
            if _MUDINFO_CHANNEL is None:
                if settings.CHANNEL_MUDINFO:
                    try:
                        _MUDINFO_CHANNEL = ChannelDB.objects.get(db_key=settings.CHANNEL_MUDINFO["key"])
                    except ChannelDB.DoesNotExist:
                        logger.log_trace()
                else:
                    _MUDINFO = False
            if _CONNECT_CHANNEL is None:
                if settings.CHANNEL_CONNECTINFO:
                    try:
                        _CONNECT_CHANNEL = ChannelDB.objects.get(
                            db_key=settings.CHANNEL_CONNECTINFO["key"]
                        )
                    except ChannelDB.DoesNotExist:
                        logger.log_trace()
                else:
                    _CONNECT_CHANNEL = False

            if settings.USE_TZ:
                now = timezone.localtime()
            else:
                now = timezone.now()
            now = "%02i-%02i-%02i(%02i:%02i)" % (now.year, now.month, now.day, now.hour, now.minute)
            if _MUDINFO_CHANNEL:
                _MUDINFO_CHANNEL.msg(f"[{now}]: {message}")
            if _CONNECT_CHANNEL:
                _CONNECT_CHANNEL.msg(f"[{now}]: {message}")

        def at_post_login(self, session=None, **kwargs):
            """
            Called at the end of the login process, just before letting
            the account loose.

            Args:
                session (Session, optional): Session logging in, if any.
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            Notes:
                This is called *before* an eventual Character's
                `at_post_login` hook. By default it is used to set up
                auto-puppeting based on `MULTISESSION_MODE`

            """
            # if we have saved protocol flags on ourselves, load them here.
            protocol_flags = self.attributes.get("_saved_protocol_flags", {})
            if session and protocol_flags:
                session.update_flags(**protocol_flags)

            # inform the client that we logged in through an OOB message
            if session:
                session.msg(logged_in={})

            self._send_to_connect_channel(_("|G{key} connected|n").format(key=self.key))
            if _AUTO_PUPPET_ON_LOGIN:
                # in this mode we try to auto-connect to our last connected object, if any
                try:
                    self.puppet_object(session, self.db._last_puppet)
                except RuntimeError:
                    self.msg(_("The Character does not exist."))
                    return
            else:
                # In this mode we don't auto-connect but by default end up at a character selection
                # screen. We execute look on the account.
                # we make sure to clean up the _playable_characters list in case
                # any was deleted in the interim.
                self.db._playable_characters = [char for char in self.db._playable_characters if char]
                self.msg(
                    self.at_look(target=self.db._playable_characters, session=session), session=session
                )

        def at_failed_login(self, session, **kwargs):
            """
            Called by the login process if a user account is targeted correctly
            but provided with an invalid password. By default it does nothing,
            but exists to be overridden.

            Args:
                session (session): Session logging in.
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).
            """
            pass

        def at_disconnect(self, reason=None, **kwargs):
            """
            Called just before user is disconnected.

            Args:
                reason (str, optional): The reason given for the disconnect,
                    (echoed to the connection channel by default).
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            """
            reason = f" ({reason if reason else ''})"
            self._send_to_connect_channel(
                _("|R{key} disconnected{reason}|n").format(key=self.key, reason=reason)
            )

        def at_post_disconnect(self, **kwargs):
            """
            This is called *after* disconnection is complete. No messages
            can be relayed to the account from here. After this call, the
            account should not be accessed any more, making this a good
            spot for deleting it (in the case of a guest account account,
            for example).

            Args:
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            """
            pass

        def at_msg_receive(self, text=None, from_obj=None, **kwargs):
            """
            This hook is called whenever someone sends a message to this
            object using the `msg` method.

            Note that from_obj may be None if the sender did not include
            itself as an argument to the obj.msg() call - so you have to
            check for this. .

            Consider this a pre-processing method before msg is passed on
            to the user session. If this method returns False, the msg
            will not be passed on.

            Args:
                text (str, optional): The message received.
                from_obj (any, optional): The object sending the message.

            Keyword Args:
                This includes any keywords sent to the `msg` method.

            Returns:
                receive (bool): If this message should be received.

            Notes:
                If this method returns False, the `msg` operation
                will abort without sending the message.

            """
            return True

        def at_msg_send(self, text=None, to_obj=None, **kwargs):
            """
            This is a hook that is called when *this* object sends a
            message to another object with `obj.msg(text, to_obj=obj)`.

            Args:
                text (str, optional): Text to send.
                to_obj (any, optional): The object to send to.

            Keyword Args:
                Keywords passed from msg()

            Notes:
                Since this method is executed by `from_obj`, if no `from_obj`
                was passed to `DefaultCharacter.msg` this hook will never
                get called.

            """
            pass

        def at_server_reload(self):
            """
            This hook is called whenever the server is shutting down for
            restart/reboot. If you want to, for example, save
            non-persistent properties across a restart, this is the place
            to do it.
            """
            pass

        def at_server_shutdown(self):
            """
            This hook is called whenever the server is shutting down fully
            (i.e. not for a restart).
            """
            pass

        ooc_appearance_template = """
    --------------------------------------------------------------------
    {header}

    {sessions}

      |whelp|n - more commands
      |wpublic <text>|n - talk on public channel
      |wcharcreate <name> [=description]|n - create new character
      |wchardelete <name>|n - delete a character
      |wic <name>|n - enter the game as character (|wooc|n to get back here)
      |wic|n - enter the game as latest character controlled.

    {characters}
    {footer}
    --------------------------------------------------------------------
    """.strip()

        def at_look(self, target=None, session=None, **kwargs):
            """
            Called when this object executes a look. It allows to customize
            just what this means.

            Args:
                target (Object or list, optional): An object or a list
                    objects to inspect. This is normally a list of characters.
                session (Session, optional): The session doing this look.
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            Returns:
                look_string (str): A prepared look string, ready to send
                    off to any recipient (usually to ourselves)

            """

            if target and not is_iter(target):
                # single target - just show it
                if hasattr(target, "return_appearance"):
                    return target.return_appearance(self)
                else:
                    return f"{target} has no in-game appearance."

            # multiple targets - this is a list of characters
            characters = list(tar for tar in target if tar) if target else []
            ncars = len(characters)
            sessions = self.sessions.all()
            nsess = len(sessions)

            if not nsess:
                # no sessions, nothing to report
                return ""

            # header text
            txt_header = f"Account |g{self.name}|n (you are Out-of-Character)"

            # sessions
            sess_strings = []
            for isess, sess in enumerate(sessions):
                ip_addr = sess.address[0] if isinstance(sess.address, tuple) else sess.address
                addr = f"{sess.protocol_key} ({ip_addr})"
                sess_str = (
                    f"|w* {isess + 1}|n"
                    if session and session.sessid == sess.sessid
                    else f"  {isess + 1}"
                )

                sess_strings.append(f"{sess_str} {addr}")

            txt_sessions = "|wConnected session(s):|n\n" + "\n".join(sess_strings)

            if not characters:
                txt_characters = "You don't have a character yet. Use |wcharcreate|n."
            else:
                max_chars = (
                    "unlimited"
                    if self.is_superuser or _MAX_NR_CHARACTERS is None
                    else _MAX_NR_CHARACTERS
                )

                char_strings = []
                for char in characters:
                    csessions = char.sessions.all()
                    if csessions:
                        for sess in csessions:
                            # character is already puppeted
                            sid = sess in sessions and sessions.index(sess) + 1
                            if sess and sid:
                                char_strings.append(
                                    f" - |G{char.name}|n [{', '.join(char.permissions.all())}] "
                                    f"(played by you in session {sid})"
                                )
                            else:
                                char_strings.append(
                                    f" - |R{char.name}|n [{', '.join(char.permissions.all())}] "
                                    "(played by someone else)"
                                )
                    else:
                        # character is "free to puppet"
                        char_strings.append(f" - {char.name} [{', '.join(char.permissions.all())}]")

                txt_characters = (
                    f"Available character(s) ({ncars}/{max_chars}, |wic <name>|n to play):|n\n"
                    + "\n".join(char_strings)
                )
            return self.ooc_appearance_template.format(
                header=txt_header,
                sessions=txt_sessions,
                characters=txt_characters,
                footer="",
            )

    class DefaultGuest(DefaultAccount):
        """
        This class is used for guest logins. Unlike Accounts, Guests and
        their characters are deleted after disconnection.

        """

        @classmethod
        def create(cls, **kwargs):
            """
            Forwards request to cls.authenticate(); returns a DefaultGuest object
            if one is available for use.

            """
            return cls.authenticate(**kwargs)

        @classmethod
        def authenticate(cls, **kwargs):
            """
            Gets or creates a Guest account object.

            Keyword Args:
                ip (str, optional): IP address of requester; used for ban checking,
                    throttling and logging

            Returns:
                account (Object): Guest account object, if available
                errors (list): List of error messages accrued during this request.

            """
            errors = []
            account = None
            username = None
            ip = kwargs.get("ip", "").strip()

            # check if guests are enabled.
            if not settings.GUEST_ENABLED:
                errors.append(_("Guest accounts are not enabled on this server."))
                return None, errors

            try:
                # Find an available guest name.
                for name in settings.GUEST_LIST:
                    if not AccountDB.objects.filter(username__iexact=name).exists():
                        username = name
                        break
                if not username:
                    errors.append(_("All guest accounts are in use. Please try again later."))
                    if ip:
                        LOGIN_THROTTLE.update(ip, "Too many requests for Guest access.")
                    return None, errors
                else:
                    # build a new account with the found guest username
                    password = "%016x" % getrandbits(64)
                    home = settings.GUEST_HOME
                    permissions = settings.PERMISSION_GUEST_DEFAULT
                    typeclass = settings.BASE_GUEST_TYPECLASS

                    # Call parent class creator
                    account, errs = super(DefaultGuest, cls).create(
                        guest=True,
                        username=username,
                        password=password,
                        permissions=permissions,
                        typeclass=typeclass,
                        home=home,
                        ip=ip,
                    )
                    errors.extend(errs)

                    if not account.characters:
                        # this can happen for multisession_mode > 1. For guests we
                        # always auto-create a character, regardless of multi-session-mode.
                        character, errs = account.create_character()

                    if errs:
                        errors.extend(errs)

                    return account, errors

            except Exception:
                # We are in the middle between logged in and -not, so we have
                # to handle tracebacks ourselves at this point. If we don't,
                # we won't see any errors at all.
                errors.append(_("An error occurred. Please e-mail an admin if the problem persists."))
                logger.log_trace()
                return None, errors

            return account, errors

        def at_post_login(self, session=None, **kwargs):
            """
            By default, Guests only have one character regardless of which
            MAX_NR_CHARACTERS we use. They also always auto-puppet a matching
            character and don't get a choice.

            Args:
                session (Session, optional): Session connecting.
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            """
            self._send_to_connect_channel(_("|G{key} connected|n").format(key=self.key))
            self.puppet_object(session, self.db._last_puppet)

        def at_server_shutdown(self):
            """
            We repeat the functionality of `at_disconnect()` here just to
            be on the safe side.
            """
            super().at_server_shutdown()
            characters = self.db._playable_characters
            if characters:
                for character in characters:
                    if character:
                        character.delete()

        def at_post_disconnect(self, **kwargs):
            """
            Once having disconnected, destroy the guest's characters and

            Args:
                **kwargs (dict): Arbitrary, optional arguments for users
                    overriding the call (unused by default).

            """
            super().at_post_disconnect()
            characters = self.db._playable_characters
            for character in characters:
                if character:
                    character.delete()
            self.delete()