# Source code for evennia.commands.default.building

    """
    Building and world design commands
    """
    import re
    from django.core.paginator import Paginator
    from django.conf import settings
    from django.db.models import Q, Min, Max
    from evennia import InterruptCommand
    from evennia.scripts.models import ScriptDB
    from evennia.objects.models import ObjectDB
    from evennia.locks.lockhandler import LockException
    from evennia.commands.cmdhandler import get_and_merge_cmdsets
    from evennia.utils import create, utils, search, logger, funcparser
    from evennia.utils.dbserialize import deserialize
    from evennia.utils.utils import (
        inherits_from,
        class_from_module,
        get_all_typeclasses,
        variable_from_module,
        dbref,
        crop,
        interactive,
        list_to_string,
        display_len,
        format_grid,
    )
    from evennia.utils.eveditor import EvEditor
    from evennia.utils.evmore import EvMore
    from evennia.utils.evtable import EvTable
    from evennia.prototypes import spawner, prototypes as protlib, menus as olc_menus
    from evennia.utils.ansi import raw as ansi_raw

    COMMAND_DEFAULT_CLASS = class_from_module(settings.COMMAND_DEFAULT_CLASS)

    _FUNCPARSER = None
    _ATTRFUNCPARSER = None

    _KEY_REGEX = re.compile(r"(?P<attr>.*?)(?P<key>(\[.*\]\ *)+)?$")

    # limit symbol import for API
    __all__ = (
        "ObjManipCommand",
        "CmdSetObjAlias",
        "CmdCopy",
        "CmdCpAttr",
        "CmdMvAttr",
        "CmdCreate",
        "CmdDesc",
        "CmdDestroy",
        "CmdDig",
        "CmdTunnel",
        "CmdLink",
        "CmdUnLink",
        "CmdSetHome",
        "CmdListCmdSets",
        "CmdName",
        "CmdOpen",
        "CmdSetAttribute",
        "CmdTypeclass",
        "CmdWipe",
        "CmdLock",
        "CmdExamine",
        "CmdFind",
        "CmdTeleport",
        "CmdScripts",
        "CmdObjects",
        "CmdTag",
        "CmdSpawn",
    )

    # used by set
    from ast import literal_eval as _LITERAL_EVAL

    LIST_APPEND_CHAR = "+"

    # used by find
    CHAR_TYPECLASS = settings.BASE_CHARACTER_TYPECLASS
    ROOM_TYPECLASS = settings.BASE_ROOM_TYPECLASS
    EXIT_TYPECLASS = settings.BASE_EXIT_TYPECLASS
    _DEFAULT_WIDTH = settings.CLIENT_DEFAULT_WIDTH

    _PROTOTYPE_PARENTS = None

    class ObjManipCommand(COMMAND_DEFAULT_CLASS):
        """
        This is a parent class for some of the defining objmanip commands
        since they tend to have some more variables to define new objects.

        Each object definition can have several components. First is
        always a name, followed by an optional alias list and finally an
        some optional data, such as a typeclass or a location. A comma ','
        separates different objects. Like this:

            name1;alias;alias;alias:option, name2;alias;alias ...

        Spaces between all components are stripped.

        A second situation is attribute manipulation. Such commands
        are simpler and offer combinations

            objname/attr/attr/attr, objname/attr, ...

        """

        # OBS - this is just a parent - it's not intended to actually be
        # included in a commandset on its own!

        def parse(self):
            """
            We need to expand the default parsing to get all
            the cases, see the module doc.
            """
            # get all the normal parsing done (switches etc)
            super().parse()

            obj_defs = ([], [])  # stores left- and right-hand side of '='
            obj_attrs = ([], [])  # "

            for iside, arglist in enumerate((self.lhslist, self.rhslist)):
                # lhslist/rhslist is already split by ',' at this point
                for objdef in arglist:
                    aliases, option, attrs = [], None, []
                    if ":" in objdef:
                        objdef, option = [part.strip() for part in objdef.rsplit(":", 1)]
                    if ";" in objdef:
                        objdef, aliases = [part.strip() for part in objdef.split(";", 1)]
                        aliases = [alias.strip() for alias in aliases.split(";") if alias.strip()]
                    if "/" in objdef:
                        objdef, attrs = [part.strip() for part in objdef.split("/", 1)]
                        _attrs = []

                        # Should an attribute key is specified, ie. we're working
                        # on a dict, what we want is to lowercase attribute name
                        # as usual but to preserve dict key case as one would
                        # expect:
                        #
                        # set box/MyAttr = {'FooBar': 1}
                        # Created attribute box/myattr [category:None] = {'FooBar': 1}
                        # set box/MyAttr['FooBar'] = 2
                        # Modified attribute box/myattr [category:None] = {'FooBar': 2}
                        for match in (
                            match
                            for part in map(str.strip, attrs.split("/"))
                            if part and (match := _KEY_REGEX.match(part.strip()))
                        ):
                            attr = match.group("attr").lower()
                            # reappend untouched key, if present
                            if match.group("key"):
                                attr += match.group("key")
                            _attrs.append(attr)
                        attrs = _attrs
                    # store data
                    obj_defs[iside].append({"name": objdef, "option": option, "aliases": aliases})
                    obj_attrs[iside].append({"name": objdef, "attrs": attrs})

            # store for future access
            self.lhs_objs = obj_defs[0]
            self.rhs_objs = obj_defs[1]
            self.lhs_objattr = obj_attrs[0]
            self.rhs_objattr = obj_attrs[1]

    class CmdSetObjAlias(COMMAND_DEFAULT_CLASS):
        """
        adding permanent aliases for object

        Usage:
          alias <obj> [= [alias[,alias,alias,...]]]
          alias <obj> =
          alias/category <obj> = [alias[,alias,...]:<category>

        Switches:
          category - requires ending input with :category, to store the
            given aliases with the given category.

        Assigns aliases to an object so it can be referenced by more
        than one name. Assign empty to remove all aliases from object. If
        assigning a category, all aliases given will be using this category.

        Observe that this is not the same thing as personal aliases
        created with the 'nick' command! Aliases set with alias are
        changing the object in question, making those aliases usable
        by everyone.
        """

        key = "@alias"
        aliases = "setobjalias"
        switch_options = ("category",)
        locks = "cmd:perm(setobjalias) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """Set the aliases."""

            caller = self.caller

            if not self.lhs:
                string = "Usage: alias <obj> [= [alias[,alias ...]]]"
                self.caller.msg(string)
                return
            objname = self.lhs

            # Find the object to receive aliases
            obj = caller.search(objname)
            if not obj:
                return
            if self.rhs is None:
                # no =, so we just list aliases on object.
                aliases = obj.aliases.all(return_key_and_category=True)
                if aliases:
                    caller.msg(
                        "Aliases for %s: %s"
                        % (
                            obj.get_display_name(caller),
                            ", ".join(
                                "'%s'%s"
                                % (alias, "" if category is None else "[category:'%s']" % category)
                                for (alias, category) in aliases
                            ),
                        )
                    )
                else:
                    caller.msg("No aliases exist for '%s'." % obj.get_display_name(caller))
                return

            if not (obj.access(caller, "control") or obj.access(caller, "edit")):
                caller.msg("You don't have permission to do that.")
                return

            if not self.rhs:
                # we have given an empty =, so delete aliases
                old_aliases = obj.aliases.all()
                if old_aliases:
                    caller.msg(
                        "Cleared aliases from %s: %s"
                        % (obj.get_display_name(caller), ", ".join(old_aliases))
                    )
                    obj.aliases.clear()
                else:
                    caller.msg("No aliases to clear.")
                return

            category = None
            if "category" in self.switches:
                if ":" in self.rhs:
                    rhs, category = self.rhs.rsplit(":", 1)
                    category = category.strip()
                else:
                    caller.msg(
                        "If specifying the /category switch, the category must be given "
                        "as :category at the end."
                    )
            else:
                rhs = self.rhs

            # merge the old and new aliases (if any)
            old_aliases = obj.aliases.get(category=category, return_list=True)
            new_aliases = [alias.strip().lower() for alias in rhs.split(",") if alias.strip()]

            # make the aliases only appear once
            old_aliases.extend(new_aliases)
            aliases = list(set(old_aliases))

            # save back to object.
            obj.aliases.add(aliases, category=category)

            # we need to trigger this here, since this will force
            # (default) Exits to rebuild their Exit commands with the new
            # aliases
            obj.at_cmdset_get(force_init=True)

            # report all aliases on the object
            caller.msg(
                "Alias(es) for '%s' set to '%s'%s."
                % (
                    obj.get_display_name(caller),
                    str(obj.aliases),
                    " (category: '%s')" % category if category else "",
                )
            )

    class CmdCopy(ObjManipCommand):
        """
        copy an object and its properties

        Usage:
          copy <original obj> [= <new_name>][;alias;alias..]
          [:<new_location>] [,<new_name2> ...]

        Create one or more copies of an object. If you don't supply any targets,
        one exact copy of the original object will be created with the name *_copy.
        """

        key = "@copy"
        locks = "cmd:perm(copy) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """Uses ObjManipCommand.parse()"""

            caller = self.caller
            args = self.args
            if not args:
                caller.msg(
                    "Usage: copy <obj> [=<new_name>[;alias;alias..]]"
                    "[:<new_location>] [, <new_name2>...]"
                )
                return

            if not self.rhs:
                # this has no target =, so an identical new object is created.
                from_obj_name = self.args
                from_obj = caller.search(from_obj_name)
                if not from_obj:
                    return
                to_obj_name = "%s_copy" % from_obj_name
                to_obj_aliases = ["%s_copy" % alias for alias in from_obj.aliases.all()]
                copiedobj = ObjectDB.objects.copy_object(
                    from_obj, new_key=to_obj_name, new_aliases=to_obj_aliases
                )
                if copiedobj:
                    string = "Identical copy of %s, named '%s' was created." % (
                        from_obj_name,
                        to_obj_name,
                    )
                else:
                    string = "There was an error copying %s."
            else:
                # we have specified =. This might mean many object targets
                from_obj_name = self.lhs_objs[0]["name"]
                from_obj = caller.search(from_obj_name)
                if not from_obj:
                    return
                for objdef in self.rhs_objs:
                    # loop through all possible copy-to targets
                    to_obj_name = objdef["name"]
                    to_obj_aliases = objdef["aliases"]
                    to_obj_location = objdef["option"]
                    if to_obj_location:
                        to_obj_location = caller.search(to_obj_location, global_search=True)
                        if not to_obj_location:
                            return

                    copiedobj = ObjectDB.objects.copy_object(
                        from_obj,
                        new_key=to_obj_name,
                        new_location=to_obj_location,
                        new_aliases=to_obj_aliases,
                    )
                    if copiedobj:
                        string = "Copied %s to '%s' (aliases: %s)." % (
                            from_obj_name,
                            to_obj_name,
                            to_obj_aliases,
                        )
                    else:
                        string = "There was an error copying %s to '%s'." % (from_obj_name, to_obj_name)
            # we are done, echo to user
            caller.msg(string)

    class CmdCpAttr(ObjManipCommand):
        """
        copy attributes between objects

        Usage:
          cpattr[/switch] <obj>/<attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
          cpattr[/switch] <obj>/<attr> = <obj1> [,<obj2>,<obj3>,...]
          cpattr[/switch] <attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
          cpattr[/switch] <attr> = <obj1>[,<obj2>,<obj3>,...]

        Switches:
          move - delete the attribute from the source object after copying.

        Example:
          cpattr coolness = Anna/chillout, Anna/nicety, Tom/nicety
          ->
          copies the coolness attribute (defined on yourself), to attributes
          on Anna and Tom.

        Copy the attribute one object to one or more attributes on another object.
        If you don't supply a source object, yourself is used.
        """

        key = "@cpattr"
        switch_options = ("move",)
        locks = "cmd:perm(cpattr) or perm(Builder)"
        help_category = "Building"

        def check_from_attr(self, obj, attr, clear=False):
            """
            Hook for overriding on subclassed commands. Checks to make sure a
            caller can copy the attr from the object in question. If not, return a
            false value and the command will abort. An error message should be
            provided by this function.

            If clear is True, user is attempting to move the attribute.
            """
            return True

        def check_to_attr(self, obj, attr):
            """
            Hook for overriding on subclassed commands. Checks to make sure a
            caller can write to the specified attribute on the specified object.
            If not, return a false value and the attribute will be skipped. An
            error message should be provided by this function.
            """
            return True

        def check_has_attr(self, obj, attr):
            """
            Hook for overriding on subclassed commands. Do any preprocessing
            required and verify an object has an attribute.
            """
            if not obj.attributes.has(attr):
                self.caller.msg("%s doesn't have an attribute %s." % (obj.name, attr))
                return False
            return True

        def get_attr(self, obj, attr):
            """
            Hook for overriding on subclassed commands. Do any preprocessing
            required and get the attribute from the object.
            """
            return obj.attributes.get(attr)

        def func(self):
            """
            Do the copying.
            """
            caller = self.caller

            if not self.rhs:
                string = """Usage:
                cpattr[/switch] <obj>/<attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
                cpattr[/switch] <obj>/<attr> = <obj1> [,<obj2>,<obj3>,...]
                cpattr[/switch] <attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
                cpattr[/switch] <attr> = <obj1>[,<obj2>,<obj3>,...]"""
                caller.msg(string)
                return

            lhs_objattr = self.lhs_objattr
            to_objs = self.rhs_objattr
            from_obj_name = lhs_objattr[0]["name"]
            from_obj_attrs = lhs_objattr[0]["attrs"]

            if not from_obj_attrs:
                # this means the from_obj_name is actually an attribute
                # name on self.
                from_obj_attrs = [from_obj_name]
                from_obj = self.caller
            else:
                from_obj = caller.search(from_obj_name)
            if not from_obj or not to_objs:
                caller.msg("You have to supply both source object and target(s).")
                return
            # copy to all to_obj:ects
            if "move" in self.switches:
                clear = True
            else:
                clear = False
            if not self.check_from_attr(from_obj, from_obj_attrs[0], clear=clear):
                return

            for attr in from_obj_attrs:
                if not self.check_has_attr(from_obj, attr):
                    return

            if (len(from_obj_attrs) != len(set(from_obj_attrs))) and clear:
                self.caller.msg("|RCannot have duplicate source names when moving!")
                return

            result = []

            for to_obj in to_objs:
                to_obj_name = to_obj["name"]
                to_obj_attrs = to_obj["attrs"]
                to_obj = caller.search(to_obj_name)
                if not to_obj:
                    result.append("\nCould not find object '%s'" % to_obj_name)
                    continue
                for inum, from_attr in enumerate(from_obj_attrs):
                    try:
                        to_attr = to_obj_attrs[inum]
                    except IndexError:
                        # if there are too few attributes given
                        # on the to_obj, we copy the original name instead.
                        to_attr = from_attr
                    if not self.check_to_attr(to_obj, to_attr):
                        continue
                    value = self.get_attr(from_obj, from_attr)
                    to_obj.attributes.add(to_attr, value)
                    if clear and not (from_obj == to_obj and from_attr == to_attr):
                        from_obj.attributes.remove(from_attr)
                        result.append(
                            "\nMoved %s.%s -> %s.%s. (value: %s)"
                            % (from_obj.name, from_attr, to_obj_name, to_attr, repr(value))
                        )
                    else:
                        result.append(
                            "\nCopied %s.%s -> %s.%s. (value: %s)"
                            % (from_obj.name, from_attr, to_obj_name, to_attr, repr(value))
                        )
            caller.msg("".join(result))

    class CmdMvAttr(ObjManipCommand):
        """
        move attributes between objects

        Usage:
          mvattr[/switch] <obj>/<attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
          mvattr[/switch] <obj>/<attr> = <obj1> [,<obj2>,<obj3>,...]
          mvattr[/switch] <attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
          mvattr[/switch] <attr> = <obj1>[,<obj2>,<obj3>,...]

        Switches:
          copy - Don't delete the original after moving.

        Move an attribute from one object to one or more attributes on another
        object. If you don't supply a source object, yourself is used.
        """

        key = "@mvattr"
        switch_options = ("copy",)
        locks = "cmd:perm(mvattr) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """
            Do the moving
            """
            if not self.rhs:
                string = """Usage:
          mvattr[/switch] <obj>/<attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
          mvattr[/switch] <obj>/<attr> = <obj1> [,<obj2>,<obj3>,...]
          mvattr[/switch] <attr> = <obj1>/<attr1> [,<obj2>/<attr2>,<obj3>/<attr3>,...]
          mvattr[/switch] <attr> = <obj1>[,<obj2>,<obj3>,...]"""
                self.caller.msg(string)
                return

            # simply use cpattr for all the functionality
            if "copy" in self.switches:
                self.execute_cmd("cpattr %s" % self.args)
            else:
                self.execute_cmd("cpattr/move %s" % self.args)

    class CmdCreate(ObjManipCommand):
        """
        create new objects

        Usage:
          create[/drop] <objname>[;alias;alias...][:typeclass], <objname>...

        switch:
           drop - automatically drop the new object into your current
                  location (this is not echoed). This also sets the new
                  object's home to the current location rather than to you.

        Creates one or more new objects. If typeclass is given, the object
        is created as a child of this typeclass. The typeclass script is
        assumed to be located under types/ and any further
        directory structure is given in Python notation. So if you have a
        correct typeclass 'RedButton' defined in
        types/examples/red_button.py, you could create a new
        object of this type like this:

           create/drop button;red : examples.red_button.RedButton

        """

        key = "@create"
        switch_options = ("drop",)
        locks = "cmd:perm(create) or perm(Builder)"
        help_category = "Building"

        # lockstring of newly created objects, for easy overloading.
        # Will be formatted with the {id} of the creating object.
        new_obj_lockstring = "control:id({id}) or perm(Admin);delete:id({id}) or perm(Admin)"

        def func(self):
            """
            Creates the object.
            """

            caller = self.caller

            if not self.args:
                string = "Usage: create[/drop] <newname>[;alias;alias...] [:typeclass.path]"
                caller.msg(string)
                return

            # create the objects
            for objdef in self.lhs_objs:
                string = ""
                name = objdef["name"]
                aliases = objdef["aliases"]
                typeclass = objdef["option"]

                # create object (if not a valid typeclass, the default
                # object typeclass will automatically be used)
                lockstring = self.new_obj_lockstring.format(id=caller.id)
                obj = create.create_object(
                    typeclass,
                    name,
                    caller,
                    home=caller,
                    aliases=aliases,
                    locks=lockstring,
                    report_to=caller,
                )
                if not obj:
                    continue
                if aliases:
                    string = "You create a new %s: %s (aliases: %s)."
                    string = string % (obj.typename, obj.name, ", ".join(aliases))
                else:
                    string = "You create a new %s: %s."
                    string = string % (obj.typename, obj.name)
                # set a default desc
                if not obj.db.desc:
                    obj.db.desc = "You see nothing special."
                if "drop" in self.switches:
                    if caller.location:
                        obj.home = caller.location
                        obj.move_to(caller.location, quiet=True, move_type="drop")
            if string:
                caller.msg(string)

    def _desc_load(caller):
        return caller.db.evmenu_target.db.desc or ""

    def _desc_save(caller, buf):
        """
        Save line buffer to the desc prop. This should
        return True if successful and also report its status to the user.
        """
        caller.db.evmenu_target.db.desc = buf
        caller.msg("Saved.")
        return True

    def _desc_quit(caller):
        caller.attributes.remove("evmenu_target")
        caller.msg("Exited editor.")

    class CmdDesc(COMMAND_DEFAULT_CLASS):
        """
        describe an object or the current room.

        Usage:
          desc [<obj> =] <description>

        Switches:
          edit - Open up a line editor for more advanced editing.

        Sets the "desc" attribute on an object. If an object is not given,
        describe the current room.
        """

        key = "@desc"
        switch_options = ("edit",)
        locks = "cmd:perm(desc) or perm(Builder)"
        help_category = "Building"

        def edit_handler(self):
            if self.rhs:
                self.msg("|rYou may specify a value, or use the edit switch, but not both.|n")
                return
            if self.args:
                obj = self.caller.search(self.args)
            else:
                obj = self.caller.location or self.msg("|rYou can't describe oblivion.|n")
            if not obj:
                return

            if not (obj.access(self.caller, "control") or obj.access(self.caller, "edit")):
                self.caller.msg("You don't have permission to edit the description of %s." % obj.key)
                return

            self.caller.db.evmenu_target = obj
            # launch the editor
            EvEditor(
                self.caller,
                loadfunc=_desc_load,
                savefunc=_desc_save,
                quitfunc=_desc_quit,
                key="desc",
                persistent=True,
            )
            return

        def func(self):
            """Define command"""

            caller = self.caller
            if not self.args and "edit" not in self.switches:
                caller.msg("Usage: desc [<obj> =] <description>")
                return

            if "edit" in self.switches:
                self.edit_handler()
                return

            if "=" in self.args:
                # We have an =
                obj = caller.search(self.lhs)
                if not obj:
                    return
                desc = self.rhs or ""
            else:
                obj = caller.location or self.msg("|rYou don't have a location to describe.|n")
                if not obj:
                    return
                desc = self.args
            if obj.access(self.caller, "control") or obj.access(self.caller, "edit"):
                obj.db.desc = desc
                caller.msg("The description was set on %s." % obj.get_display_name(caller))
            else:
                caller.msg("You don't have permission to edit the description of %s." % obj.key)

    class CmdDestroy(COMMAND_DEFAULT_CLASS):
        """
        permanently delete objects

        Usage:
           destroy[/switches] [obj, obj2, obj3, [dbref-dbref], ...]

        Switches:
           override - The destroy command will usually avoid accidentally
                      destroying account objects. This switch overrides this safety.
           force - destroy without confirmation.
        Examples:
           destroy house, roof, door, 44-78
           destroy 5-10, flower, 45
           destroy/force north

        Destroys one or many objects. If dbrefs are used, a range to delete can be
        given, e.g. 4-10. Also the end points will be deleted. This command
        displays a confirmation before destroying, to make sure of your choice.
        You can specify the /force switch to bypass this confirmation.
        """

        key = "@destroy"
        aliases = ["@delete", "@del"]
        switch_options = ("override", "force")
        locks = "cmd:perm(destroy) or perm(Builder)"
        help_category = "Building"

        confirm = True  # set to False to always bypass confirmation
        default_confirm = "yes"  # what to assume if just pressing enter (yes/no)

        def func(self):
            """Implements the command."""

            caller = self.caller
            delete = True

            if not self.args or not self.lhslist:
                caller.msg("Usage: destroy[/switches] [obj, obj2, obj3, [dbref-dbref],...]")
                delete = False

            def delobj(obj):
                # helper function for deleting a single object
                string = ""
                if not obj.pk:
                    string = "\nObject %s was already deleted." % obj.db_key
                else:
                    objname = obj.name
                    if not (obj.access(caller, "control") or obj.access(caller, "delete")):
                        return "\nYou don't have permission to delete %s." % objname
                    if obj.account and "override" not in self.switches:
                        return (
                            "\nObject %s is controlled by an active account. Use /override to delete anyway."
                            % objname
                        )
                    if obj.dbid == int(settings.DEFAULT_HOME.lstrip("#")):
                        return (
                            "\nYou are trying to delete |c%s|n, which is set as DEFAULT_HOME. "
                            "Re-point settings.DEFAULT_HOME to another "
                            "object before continuing." % objname
                        )

                    had_exits = hasattr(obj, "exits") and obj.exits
                    had_objs = hasattr(obj, "contents") and any(
                        obj
                        for obj in obj.contents
                        if not (hasattr(obj, "exits") and obj not in obj.exits)
                    )
                    # do the deletion
                    okay = obj.delete()
                    if not okay:
                        string += (
                            "\nERROR: %s not deleted, probably because delete() returned False."
                            % objname
                        )
                    else:
                        string += "\n%s was destroyed." % objname
                        if had_exits:
                            string += " Exits to and from %s were destroyed as well." % objname
                        if had_objs:
                            string += " Objects inside %s were moved to their homes." % objname
                return string

            objs = []
            for objname in self.lhslist:
                if not delete:
                    continue

                if "-" in objname:
                    # might be a range of dbrefs
                    dmin, dmax = [utils.dbref(part, reqhash=False) for part in objname.split("-", 1)]
                    if dmin and dmax:
                        for dbref in range(int(dmin), int(dmax + 1)):
                            obj = caller.search("#" + str(dbref))
                            if obj:
                                objs.append(obj)
                        continue
                    else:
                        obj = caller.search(objname)
                else:
                    obj = caller.search(objname)

                if obj is None:
                    self.caller.msg(
                        " (Objects to destroy must either be local or specified with a unique #dbref.)"
                    )
                elif obj not in objs:
                    objs.append(obj)

            if objs and ("force" not in self.switches and type(self).confirm):
                confirm = "Are you sure you want to destroy "
                if len(objs) == 1:
                    confirm += objs[0].get_display_name(caller)
                elif len(objs) < 5:
                    confirm += ", ".join([obj.get_display_name(caller) for obj in objs])
                else:
                    confirm += ", ".join(["#{}".format(obj.id) for obj in objs])
                confirm += " [yes]/no?" if self.default_confirm == "yes" else " yes/[no]"
                answer = ""
                answer = yield (confirm)
                answer = self.default_confirm if answer == "" else answer

                if answer and answer not in ("yes", "y", "no", "n"):
                    caller.msg(
                        "Canceled: Either accept the default by pressing return or specify yes/no."
                    )
                    delete = False
                elif answer.strip().lower() in ("n", "no"):
                    caller.msg("Canceled: No object was destroyed.")
                    delete = False

            if delete:
                results = []
                for obj in objs:
                    results.append(delobj(obj))

                if results:
                    caller.msg("".join(results).strip())

    class CmdDig(ObjManipCommand):
        """
        build new rooms and connect them to the current location

        Usage:
          dig[/switches] <roomname>[;alias;alias...][:typeclass]
                [= <exit_to_there>[;alias][:typeclass]]
                   [, <exit_to_here>[;alias][:typeclass]]

        Switches:
           tel or teleport - move yourself to the new room

        Examples:
           dig kitchen = north;n, south;s
           dig house:myrooms.MyHouseTypeclass
           dig sheer cliff;cliff;sheer = climb up, climb down

        This command is a convenient way to build rooms quickly; it creates the
        new room and you can optionally set up exits back and forth between your
        current room and the new one. You can add as many aliases as you
        like to the name of the room and the exits in question; an example
        would be 'north;no;n'.
        """

        key = "@dig"
        switch_options = ("teleport",)
        locks = "cmd:perm(dig) or perm(Builder)"
        help_category = "Building"

        # lockstring of newly created rooms, for easy overloading.
        # Will be formatted with the {id} of the creating object.
        new_room_lockstring = (
            "control:id({id}) or perm(Admin); "
            "delete:id({id}) or perm(Admin); "
            "edit:id({id}) or perm(Admin)"
        )

        def func(self):
            """Do the digging. Inherits variables from ObjManipCommand.parse()"""

            caller = self.caller

            if not self.lhs:
                string = "Usage: dig[/teleport] <roomname>[;alias;alias...]" "[:parent] [= <exit_there>"
                string += "[;alias;alias..][:parent]] "
                string += "[, <exit_back_here>[;alias;alias..][:parent]]"
                caller.msg(string)
                return

            room = self.lhs_objs[0]

            if not room["name"]:
                caller.msg("You must supply a new room name.")
                return
            location = caller.location

            # Create the new room
            typeclass = room["option"]
            if not typeclass:
                typeclass = settings.BASE_ROOM_TYPECLASS

            # create room
            new_room = create.create_object(
                typeclass, room["name"], aliases=room["aliases"], report_to=caller
            )
            lockstring = self.new_room_lockstring.format(id=caller.id)
            new_room.locks.add(lockstring)
            alias_string = ""
            if new_room.aliases.all():
                alias_string = " (%s)" % ", ".join(new_room.aliases.all())
            room_string = "Created room %s(%s)%s of type %s." % (
                new_room,
                new_room.dbref,
                alias_string,
                typeclass,
            )

            # create exit to room

            exit_to_string = ""
            exit_back_string = ""

            if self.rhs_objs:
                to_exit = self.rhs_objs[0]
                if not to_exit["name"]:
                    exit_to_string = "\nNo exit created to new room."
                elif not location:
                    exit_to_string = "\nYou cannot create an exit from a None-location."
                else:
                    # Build the exit to the new room from the current one
                    typeclass = to_exit["option"]
                    if not typeclass:
                        typeclass = settings.BASE_EXIT_TYPECLASS

                    new_to_exit = create.create_object(
                        typeclass,
                        to_exit["name"],
                        location,
                        aliases=to_exit["aliases"],
                        locks=lockstring,
                        destination=new_room,
                        report_to=caller,
                    )
                    alias_string = ""
                    if new_to_exit.aliases.all():
                        alias_string = " (%s)" % ", ".join(new_to_exit.aliases.all())
                    exit_to_string = "\nCreated Exit from %s to %s: %s(%s)%s."
                    exit_to_string = exit_to_string % (
                        location.name,
                        new_room.name,
                        new_to_exit,
                        new_to_exit.dbref,
                        alias_string,
                    )

            # Create exit back from new room

            if len(self.rhs_objs) > 1:
                # Building the exit back to the current room
                back_exit = self.rhs_objs[1]
                if not back_exit["name"]:
                    exit_back_string = "\nNo back exit created."
                elif not location:
                    exit_back_string = "\nYou cannot create an exit back to a None-location."
                else:
                    typeclass = back_exit["option"]
                    if not typeclass:
                        typeclass = settings.BASE_EXIT_TYPECLASS
                    new_back_exit = create.create_object(
                        typeclass,
                        back_exit["name"],
                        new_room,
                        aliases=back_exit["aliases"],
                        locks=lockstring,
                        destination=location,
                        report_to=caller,
                    )
                    alias_string = ""
                    if new_back_exit.aliases.all():
                        alias_string = " (%s)" % ", ".join(new_back_exit.aliases.all())
                    exit_back_string = "\nCreated Exit back from %s to %s: %s(%s)%s."
                    exit_back_string = exit_back_string % (
                        new_room.name,
                        location.name,
                        new_back_exit,
                        new_back_exit.dbref,
                        alias_string,
                    )
            caller.msg("%s%s%s" % (room_string, exit_to_string, exit_back_string))
            if new_room and "teleport" in self.switches:
                caller.move_to(new_room, move_type="teleport")

    class CmdTunnel(COMMAND_DEFAULT_CLASS):
        """
        create new rooms in cardinal directions only

        Usage:
          tunnel[/switch] <direction>[:typeclass] [= <roomname>[;alias;alias;...][:typeclass]]

        Switches:
          oneway - do not create an exit back to the current location
          tel - teleport to the newly created room

        Example:
          tunnel n
          tunnel n = house;mike's place;green building

        This is a simple way to build using pre-defined directions:
         |wn,ne,e,se,s,sw,w,nw|n (north, northeast etc)
         |wu,d|n (up and down)
         |wi,o|n (in and out)
        The full names (north, in, southwest, etc) will always be put as
        main name for the exit, using the abbreviation as an alias (so an
        exit will always be able to be used with both "north" as well as
        "n" for example). Opposite directions will automatically be
        created back from the new room unless the /oneway switch is given.
        For more flexibility and power in creating rooms, use dig.
        """

        key = "@tunnel"
        aliases = ["@tun"]
        switch_options = ("oneway", "tel")
        locks = "cmd: perm(tunnel) or perm(Builder)"
        help_category = "Building"

        # store the direction, full name and its opposite
        directions = {
            "n": ("north", "s"),
            "ne": ("northeast", "sw"),
            "e": ("east", "w"),
            "se": ("southeast", "nw"),
            "s": ("south", "n"),
            "sw": ("southwest", "ne"),
            "w": ("west", "e"),
            "nw": ("northwest", "se"),
            "u": ("up", "d"),
            "d": ("down", "u"),
            "i": ("in", "o"),
            "o": ("out", "i"),
        }

        def func(self):
            """Implements the tunnel command"""

            if not self.args or not self.lhs:
                string = (
                    "Usage: tunnel[/switch] <direction>[:typeclass] [= <roomname>"
                    "[;alias;alias;...][:typeclass]]"
                )
                self.caller.msg(string)
                return

            # If we get a typeclass, we need to get just the exitname
            exitshort = self.lhs.split(":")[0]

            if exitshort not in self.directions:
                string = "tunnel can only understand the following directions: %s." % ",".join(
                    sorted(self.directions.keys())
                )
                string += "\n(use dig for more freedom)"
                self.caller.msg(string)
                return

            # retrieve all input and parse it
            exitname, backshort = self.directions[exitshort]
            backname = self.directions[backshort][0]

            # if we received a typeclass for the exit, add it to the alias(short name)
            if ":" in self.lhs:
                # limit to only the first : character
                exit_typeclass = ":" + self.lhs.split(":", 1)[-1]
                # exitshort and backshort are the last part of the exit strings,
                # so we add our typeclass argument after
                exitshort += exit_typeclass
                backshort += exit_typeclass

            roomname = "Some place"
            if self.rhs:
                roomname = self.rhs  # this may include aliases; that's fine.

            telswitch = ""
            if "tel" in self.switches:
                telswitch = "/teleport"
            backstring = ""
            if "oneway" not in self.switches:
                backstring = ", %s;%s" % (backname, backshort)

            # build the string we will use to call dig
            digstring = "dig%s %s = %s;%s%s" % (telswitch, roomname, exitname, exitshort, backstring)
            self.execute_cmd(digstring)

    class CmdLink(COMMAND_DEFAULT_CLASS):
        """
        link existing rooms together with exits

        Usage:
          link[/switches] <object> = <target>
          link[/switches] <object> =
          link[/switches] <object>

        Switch:
          twoway - connect two exits. For this to work, BOTH <object>
                   and <target> must be exit objects.

        If <object> is an exit, set its destination to <target>. Two-way operation
        instead sets the destination to the *locations* of the respective given
        arguments.
        The second form (a lone =) sets the destination to None (same as
        the unlink command) and the third form (without =) just shows the
        currently set destination.
        """

        key = "@link"
        locks = "cmd:perm(link) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """Perform the link"""
            caller = self.caller

            if not self.args:
                caller.msg("Usage: link[/twoway] <object> = <target>")
                return

            object_name = self.lhs

            # try to search locally first
            results = caller.search(object_name, quiet=True)
            if len(results) > 1:  # local results was a multimatch. Inform them to be more specific
                _AT_SEARCH_RESULT = variable_from_module(*settings.SEARCH_AT_RESULT.rsplit(".", 1))
                return _AT_SEARCH_RESULT(results, caller, query=object_name)
            elif len(results) == 1:  # A unique local match
                obj = results[0]
            else:  # No matches. Search globally
                obj = caller.search(object_name, global_search=True)
                if not obj:
                    return

            if self.rhs:
                # this means a target name was given
                target = caller.search(self.rhs, global_search=True)
                if not target:
                    return

                if target == obj:
                    self.caller.msg("Cannot link an object to itself.")
                    return

                string = ""
                note = "Note: %s(%s) did not have a destination set before. Make sure you linked the right thing."
                if not obj.destination:
                    string = note % (obj.name, obj.dbref)
                if "twoway" in self.switches:
                    if not (target.location and obj.location):
                        string = "To create a two-way link, %s and %s must both have a location" % (
                            obj,
                            target,
                        )
                        string += " (i.e. they cannot be rooms, but should be exits)."
                        self.caller.msg(string)
                        return
                    if not target.destination:
                        string += note % (target.name, target.dbref)
                    obj.destination = target.location
                    target.destination = obj.location
                    string += "\nLink created %s (in %s) <-> %s (in %s) (two-way)." % (
                        obj.name,
                        obj.location,
                        target.name,
                        target.location,
                    )
                else:
                    obj.destination = target
                    string += "\nLink created %s -> %s (one way)." % (obj.name, target)

            elif self.rhs is None:
                # this means that no = was given (otherwise rhs
                # would have been an empty string). So we inspect
                # the home/destination on object
                dest = obj.destination
                if dest:
                    string = "%s is an exit to %s." % (obj.name, dest.name)
                else:
                    string = "%s is not an exit. Its home location is %s." % (obj.name, obj.home)

            else:
                # We gave the command link 'obj = ' which means we want to
                # clear destination.
                if obj.destination:
                    obj.destination = None
                    string = "Former exit %s no longer links anywhere." % obj.name
                else:
                    string = "%s had no destination to unlink." % obj.name
            # give feedback
            caller.msg(string.strip())

    class CmdUnLink(CmdLink):
        """
        remove exit-connections between rooms

        Usage:
          unlink <Object>

        Unlinks an object, for example an exit, disconnecting
        it from whatever it was connected to.
        """

        # this is just a child of CmdLink

        key = "unlink"
        locks = "cmd:perm(unlink) or perm(Builder)"
        help_key = "Building"

        def func(self):
            """
            All we need to do here is to set the right command
            and call func in CmdLink
            """

            caller = self.caller

            if not self.args:
                caller.msg("Usage: unlink <object>")
                return

            # This mimics 'link <obj> = ' which is the same as unlink
            self.rhs = ""

            # call the link functionality
            super().func()

    class CmdSetHome(CmdLink):
        """
        set an object's home location

        Usage:
          sethome <obj> [= <home_location>]
          sethom <obj>

        The "home" location is a "safety" location for objects; they
        will be moved there if their current location ceases to exist. All
        objects should always have a home location for this reason.
        It is also a convenient target of the "home" command.

        If no location is given, just view the object's home location.
        """

        key = "@sethome"
        locks = "cmd:perm(sethome) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """implement the command"""
            if not self.args:
                string = "Usage: sethome <obj> [= <home_location>]"
                self.caller.msg(string)
                return

            obj = self.caller.search(self.lhs, global_search=True)
            if not obj:
                return
            if not self.rhs:
                # just view
                home = obj.home
                if not home:
                    string = "This object has no home location set!"
                else:
                    string = "%s's current home is %s(%s)." % (obj, home, home.dbref)
            else:
                # set a home location
                new_home = self.caller.search(self.rhs, global_search=True)
                if not new_home:
                    return
                old_home = obj.home
                obj.home = new_home
                if old_home:
                    string = "Home location of %s was changed from %s(%s) to %s(%s)." % (
                        obj,
                        old_home,
                        old_home.dbref,
                        new_home,
                        new_home.dbref,
                    )
                else:
                    string = "Home location of %s was set to %s(%s)." % (obj, new_home, new_home.dbref)
            self.caller.msg(string)

    class CmdListCmdSets(COMMAND_DEFAULT_CLASS):
        """
        list command sets defined on an object

        Usage:
          cmdsets <obj>

        This displays all cmdsets assigned
        to a user. Defaults to yourself.
        """

        key = "@cmdsets"
        locks = "cmd:perm(listcmdsets) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """list the cmdsets"""

            caller = self.caller
            if self.arglist:
                obj = caller.search(self.arglist[0])
                if not obj:
                    return
            else:
                obj = caller
            string = "%s" % obj.cmdset
            caller.msg(string)

    class CmdName(ObjManipCommand):
        """
        change the name and/or aliases of an object

        Usage:
          name <obj> = <newname>;alias1;alias2

        Rename an object to something new. Use *obj to
        rename an account.

        """

        key = "@name"
        aliases = ["@rename"]
        locks = "cmd:perm(rename) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """change the name"""

            caller = self.caller
            if not self.args:
                caller.msg("Usage: name <obj> = <newname>[;alias;alias;...]")
                return

            obj = None
            if self.lhs_objs:
                objname = self.lhs_objs[0]["name"]
                if objname.startswith("*"):
                    # account mode
                    obj = caller.account.search(objname.lstrip("*"))
                    if obj:
                        if self.rhs_objs[0]["aliases"]:
                            caller.msg("Accounts can't have aliases.")
                            return
                        newname = self.rhs
                        if not newname:
                            caller.msg("No name defined!")
                            return
                        if not (obj.access(caller, "control") or obj.access(caller, "edit")):
                            caller.msg("You don't have right to edit this account %s." % obj)
                            return
                        obj.username = newname
                        obj.save()
                        caller.msg("Account's name changed to '%s'." % newname)
                        return
                # object search, also with *
                obj = caller.search(objname)
                if not obj:
                    return
            if self.rhs_objs:
                newname = self.rhs_objs[0]["name"]
                aliases = self.rhs_objs[0]["aliases"]
            else:
                newname = self.rhs
                aliases = None
            if not newname and not aliases:
                caller.msg("No names or aliases defined!")
                return
            if not (obj.access(caller, "control") or obj.access(caller, "edit")):
                caller.msg("You don't have the right to edit %s." % obj)
                return
            # change the name and set aliases:
            if newname:
                obj.key = newname
            astring = ""
            if aliases:
                [obj.aliases.add(alias) for alias in aliases]
                astring = " (%s)" % (", ".join(aliases))
            # fix for exits - we need their exit-command to change name too
            if obj.destination:
                obj.flush_from_cache(force=True)
            caller.msg("Object's name changed to '%s'%s." % (newname, astring))

    class CmdOpen(ObjManipCommand):
        """
        open a new exit from the current room

        Usage:
          open <new exit>[;alias;alias..][:typeclass] [,<return exit>[;alias;..][:typeclass]]] = <destination>

        Handles the creation of exits. If a destination is given, the exit
        will point there. The <return exit> argument sets up an exit at the
        destination leading back to the current room. Destination name
        can be given both as a #dbref and a name, if that name is globally
        unique.

        """

        key = "@open"
        locks = "cmd:perm(open) or perm(Builder)"
        help_category = "Building"

        new_obj_lockstring = "control:id({id}) or perm(Admin);delete:id({id}) or perm(Admin)"
        # a custom member method to chug out exits and do checks
        def create_exit(self, exit_name, location, destination, exit_aliases=None, typeclass=None):
            """
            Helper function to avoid code duplication.
            At this point we know destination is a valid location

            """
            caller = self.caller
            string = ""
            # check if this exit object already exists at the location.
            # we need to ignore errors (so no automatic feedback)since we
            # have to know the result of the search to decide what to do.
            exit_obj = caller.search(exit_name, location=location, quiet=True, exact=True)
            if len(exit_obj) > 1:
                # give error message and return
                caller.search(exit_name, location=location, exact=True)
                return None
            if exit_obj:
                exit_obj = exit_obj[0]
                if not exit_obj.destination:
                    # we are trying to link a non-exit
                    string = "'%s' already exists and is not an exit!\nIf you want to convert it "
                    string += (
                        "to an exit, you must assign an object to the 'destination' property first."
                    )
                    caller.msg(string % exit_name)
                    return None
                # we are re-linking an old exit.
                old_destination = exit_obj.destination
                if old_destination:
                    string = "Exit %s already exists." % exit_name
                    if old_destination.id != destination.id:
                        # reroute the old exit.
                        exit_obj.destination = destination
                        if exit_aliases:
                            [exit_obj.aliases.add(alias) for alias in exit_aliases]
                        string += " Rerouted its old destination '%s' to '%s' and changed aliases." % (
                            old_destination.name,
                            destination.name,
                        )
                    else:
                        string += " It already points to the correct place."

            else:
                # exit does not exist before. Create a new one.
                lockstring = self.new_obj_lockstring.format(id=caller.id)
                if not typeclass:
                    typeclass = settings.BASE_EXIT_TYPECLASS
                exit_obj = create.create_object(
                    typeclass,
                    key=exit_name,
                    location=location,
                    aliases=exit_aliases,
                    locks=lockstring,
                    report_to=caller,
                )
                if exit_obj:
                    # storing a destination is what makes it an exit!
                    exit_obj.destination = destination
                    string = (
                        ""
                        if not exit_aliases
                        else " (aliases: %s)" % (", ".join([str(e) for e in exit_aliases]))
                    )
                    string = "Created new Exit '%s' from %s to %s%s." % (
                        exit_name,
                        location.name,
                        destination.name,
                        string,
                    )
                else:
                    string = "Error: Exit '%s' not created." % exit_name
            # emit results
            caller.msg(string)
            return exit_obj

        def parse(self):
            super().parse()
            self.location = self.caller.location
            if not self.args or not self.rhs:
                self.caller.msg(
                    "Usage: open <new exit>[;alias...][:typeclass]"
                    "[,<return exit>[;alias..][:typeclass]]] "
                    "= <destination>"
                )
                raise InterruptCommand
            if not self.location:
                self.caller.msg("You cannot create an exit from a None-location.")
                raise InterruptCommand
            self.destination = self.caller.search(self.rhs, global_search=True)
            if not self.destination:
                raise InterruptCommand
            self.exit_name = self.lhs_objs[0]["name"]
            self.exit_aliases = self.lhs_objs[0]["aliases"]
            self.exit_typeclass = self.lhs_objs[0]["option"]

        def func(self):
            """
            This is where the processing starts.
            Uses the ObjManipCommand.parser() for pre-processing
            as well as the self.create_exit() method.
            """
            # Create exit
            ok = self.create_exit(
                self.exit_name, self.location, self.destination, self.exit_aliases, self.exit_typeclass
            )
            if not ok:
                # an error; the exit was not created, so we quit.
                return
            # Create back exit, if any
            if len(self.lhs_objs) > 1:
                back_exit_name = self.lhs_objs[1]["name"]
                back_exit_aliases = self.lhs_objs[1]["aliases"]
                back_exit_typeclass = self.lhs_objs[1]["option"]
                self.create_exit(
                    back_exit_name,
                    self.destination,
                    self.location,
                    back_exit_aliases,
                    back_exit_typeclass,
                )

    def _convert_from_string(cmd, strobj):
        """
        Converts a single object in *string form* to its equivalent python
        type.

         Python earlier than 2.6:
        Handles floats, ints, and limited nested lists and dicts
        (can't handle lists in a dict, for example, this is mainly due to
        the complexity of parsing this rather than any technical difficulty -
        if there is a need for set-ing such complex structures on the
        command line we might consider adding it).
         Python 2.6 and later:
        Supports all Python structures through literal_eval as long as they
        are valid Python syntax. If they are not (such as [test, test2], ie
        without the quotes around the strings), the entire structure will
        be converted to a string and a warning will be given.

        We need to convert like this since all data being sent over the
        telnet connection by the Account is text - but we will want to
        store it as the "real" python type so we can do convenient
        comparisons later (e.g.  obj.db.value = 2, if value is stored as a
        string this will always fail).
        """

        # Use literal_eval to parse python structure exactly.
        try:
            return _LITERAL_EVAL(strobj)
        except (SyntaxError, ValueError):
            # treat as string
            strobj = utils.to_str(strobj)
            string = (
                '|RNote: name "|r%s|R" was converted to a string. '
                "Make sure this is acceptable." % strobj
            )
            cmd.caller.msg(string)
            return strobj
        except Exception as err:
            string = "|RUnknown error in evaluating Attribute: {}".format(err)
            return string

    class CmdSetAttribute(ObjManipCommand):
        """
        set attribute on an object or account

        Usage:
          set[/switch] <obj>/<attr>[:category] = <value>
          set[/switch] <obj>/<attr>[:category] =                  # delete attribute
          set[/switch] <obj>/<attr>[:category]                    # view attribute
          set[/switch] *<account>/<attr>[:category] = <value>

        Switch:
            edit: Open the line editor (string values only)
            script: If we're trying to set an attribute on a script
            channel: If we're trying to set an attribute on a channel
            account: If we're trying to set an attribute on an account
            room: Setting an attribute on a room (global search)
            exit: Setting an attribute on an exit (global search)
            char: Setting an attribute on a character (global search)
            character: Alias for char, as above.

        Example:
            set self/foo = "bar"
            set/delete self/foo
            set self/foo = $dbref(#53)

        Sets attributes on objects. The second example form above clears a
        previously set attribute while the third form inspects the current value of
        the attribute (if any). The last one (with the star) is a shortcut for
        operating on a player Account rather than an Object.

        If you want <value> to be an object, use $dbef(#dbref) or
        $search(key) to assign it. You need control or edit access to
        the object you are adding.

        The most common data to save with this command are strings and
        numbers. You can however also set Python primitives such as lists,
        dictionaries and tuples on objects (this might be important for
        the functionality of certain custom objects).  This is indicated
        by you starting your value with one of |c'|n, |c"|n, |c(|n, |c[|n
        or |c{ |n.

        Once you have stored a Python primitive as noted above, you can include
        |c[<key>]|n in <attr> to reference nested values in e.g. a list or dict.

        Remember that if you use Python primitives like this, you must
        write proper Python syntax too - notably you must include quotes
        around your strings or you will get an error.

        """

        key = "@set"
        locks = "cmd:perm(set) or perm(Builder)"
        help_category = "Building"
        nested_re = re.compile(r"\[.*?\]")
        not_found = object()

        def check_obj(self, obj):
            """
            This may be overridden by subclasses in case restrictions need to be
            placed on whether certain objects can have attributes set by certain
            accounts.

            This function is expected to display its own error message.

            Returning False will abort the command.
            """
            return True

        def check_attr(self, obj, attr_name, category):
            """
            This may be overridden by subclasses in case restrictions need to be
            placed on what attributes can be set by who beyond the normal lock.

            This functions is expected to display its own error message. It is
            run once for every attribute that is checked, blocking only those
            attributes which are not permitted and letting the others through.
            """
            return attr_name

        def split_nested_attr(self, attr):
            """
            Yields tuples of (possible attr name, nested keys on that attr).
            For performance, this is biased to the deepest match, but allows compatibility
            with older attrs that might have been named with `[]`'s.

            > list(split_nested_attr("nested['asdf'][0]"))
            [
                ('nested', ['asdf', 0]),
                ("nested['asdf']", [0]),
                ("nested['asdf'][0]", []),
            ]
            """
            quotes = "\"'"

            def clean_key(val):
                val = val.strip("[]")
                if val[0] in quotes:
                    return val.strip(quotes)
                if val[0] == LIST_APPEND_CHAR:
                    # List insert/append syntax
                    return val
                try:
                    return int(val)
                except ValueError:
                    return val

            parts = self.nested_re.findall(attr)

            base_attr = ""
            if parts:
                base_attr = attr[: attr.find(parts[0])]
            for index, part in enumerate(parts):
                yield (base_attr, [clean_key(p) for p in parts[index:]])
                base_attr += part
            yield (attr, [])

        def do_nested_lookup(self, value, *keys):
            result = value
            for key in keys:
                try:
                    result = result.__getitem__(key)
                except (IndexError, KeyError, TypeError):
                    return self.not_found
            return result

        def view_attr(self, obj, attr, category):
            """
            Look up the value of an attribute and return a string displaying it.
            """
            nested = False
            for key, nested_keys in self.split_nested_attr(attr):
                nested = True
                if obj.attributes.has(key):
                    val = obj.attributes.get(key)
                    val = self.do_nested_lookup(val, *nested_keys)
                    if val is not self.not_found:
                        return f"\nAttribute {obj.name}/|w{attr}|n [category:{category}] = {val}"
            error = f"\nAttribute {obj.name}/|w{attr} [category:{category}] does not exist."
            if nested:
                error += " (Nested lookups attempted)"
            return error

        def rm_attr(self, obj, attr, category):
            """
            Remove an attribute from the object, or a nested data structure, and report back.
            """
            nested = False
            for key, nested_keys in self.split_nested_attr(attr):
                nested = True
                if obj.attributes.has(key, category):
                    if nested_keys:
                        del_key = nested_keys[-1]
                        val = obj.attributes.get(key, category=category)
                        deep = self.do_nested_lookup(val, *nested_keys[:-1])
                        if deep is not self.not_found:
                            try:
                                del deep[del_key]
                            except (IndexError, KeyError, TypeError):
                                continue
                        return f"\nDeleted attribute {obj.name}/|w{attr}|n [category:{category}]."
                    else:
                        exists = obj.attributes.has(key, category)
                        if exists:
                            obj.attributes.remove(attr, category=category)
                            return f"\nDeleted attribute {obj.name}/|w{attr}|n [category:{category}]."
                        else:
                            return (
                                f"\nNo attribute {obj.name}/|w{attr}|n [category: {category}] "
                                "was found to delete."
                            )
            error = f"\nNo attribute {obj.name}/|w{attr}|n [category: {category}] was found to delete."
            if nested:
                error += " (Nested lookups attempted)"
            return error

        def set_attr(self, obj, attr, value, category):
            done = False
            for key, nested_keys in self.split_nested_attr(attr):
                if obj.attributes.has(key, category) and nested_keys:
                    acc_key = nested_keys[-1]
                    lookup_value = obj.attributes.get(key, category)
                    deep = self.do_nested_lookup(lookup_value, *nested_keys[:-1])
                    if deep is not self.not_found:
                        # To support appending and inserting to lists
                        # a key that starts with LIST_APPEND_CHAR will insert a new item at that
                        # location, and move the other elements down.
                        # Using LIST_APPEND_CHAR alone will append to the list
                        if isinstance(acc_key, str) and acc_key[0] == LIST_APPEND_CHAR:
                            try:
                                if len(acc_key) > 1:
                                    where = int(acc_key[1:])
                                    deep.insert(where, value)
                                else:
                                    deep.append(value)
                            except (ValueError, AttributeError):
                                pass
                            else:
                                value = lookup_value
                                attr = key
                                done = True
                                break

                        # List magic failed, just use like a key/index
                        try:
                            deep[acc_key] = value
                        except TypeError as err:
                            # Tuples can't be modified
                            return f"\n{err} - {deep}"

                        value = lookup_value
                        attr = key
                        done = True
                        break

            verb = "Modified" if obj.attributes.has(attr) else "Created"
            try:
                if not done:
                    obj.attributes.add(attr, value, category)
                return f"\n{verb} attribute {obj.name}/|w{attr}|n [category:{category}] = {value}"
            except SyntaxError:
                # this means literal_eval tried to parse a faulty string
                return (
                    "\n|RCritical Python syntax error in your value. Only "
                    "primitive Python structures are allowed.\nYou also "
                    "need to use correct Python syntax. Remember especially "
                    "to put quotes around all strings inside lists and "
                    "dicts.|n"
                )

        @interactive
        def edit_handler(self, obj, attr, caller):
            """Activate the line editor"""

            def load(caller):
                """Called for the editor to load the buffer"""

                try:
                    old_value = obj.attributes.get(attr, raise_exception=True)
                except AttributeError:
                    # we set empty buffer on nonexisting Attribute because otherwise
                    # we'd always have the string "None" in the buffer to start with
                    old_value = ""
                return str(old_value)  # we already confirmed we are ok with this

            def save(caller, buf):
                """Called when editor saves its buffer."""
                obj.attributes.add(attr, buf)
                caller.msg("Saved Attribute %s." % attr)

            # check non-strings before activating editor
            try:
                old_value = obj.attributes.get(attr, raise_exception=True)
                if not isinstance(old_value, str):
                    answer = yield (
                        f"|rWarning: Attribute |w{attr}|r is of type |w{type(old_value).__name__}|r. "
                        "\nTo continue editing, it must be converted to (and saved as) a string. "
                        "Continue? [Y]/N?"
                    )
                    if answer.lower() in ("n", "no"):
                        self.caller.msg("Aborted edit.")
                        return
            except AttributeError:
                pass

            # start the editor
            EvEditor(self.caller, load, save, key=f"{obj}/{attr}")

        def search_for_obj(self, objname):
            """
            Searches for an object matching objname. The object may be of different typeclasses.
            Args:
                objname: Name of the object we're looking for

            Returns:
                A typeclassed object, or None if nothing is found.
            """
            from evennia.utils.utils import variable_from_module

            _AT_SEARCH_RESULT = variable_from_module(*settings.SEARCH_AT_RESULT.rsplit(".", 1))
            caller = self.caller
            if objname.startswith("*") or "account" in self.switches:
                found_obj = caller.search_account(objname.lstrip("*"))
            elif "script" in self.switches:
                found_obj = _AT_SEARCH_RESULT(search.search_script(objname), caller)
            elif "channel" in self.switches:
                found_obj = _AT_SEARCH_RESULT(search.search_channel(objname), caller)
            else:
                global_search = True
                if "char" in self.switches or "character" in self.switches:
                    typeclass = settings.BASE_CHARACTER_TYPECLASS
                elif "room" in self.switches:
                    typeclass = settings.BASE_ROOM_TYPECLASS
                elif "exit" in self.switches:
                    typeclass = settings.BASE_EXIT_TYPECLASS
                else:
                    global_search = False
                    typeclass = None
                found_obj = caller.search(objname, global_search=global_search, typeclass=typeclass)
            return found_obj

        def func(self):
            """Implement the set attribute - a limited form of py."""

            caller = self.caller
            if not self.args:
                caller.msg("Usage: set obj/attr[:category] = value. Use empty value to clear.")
                return

            # get values prepared by the parser
            value = self.rhs
            objname = self.lhs_objattr[0]["name"]
            attrs = self.lhs_objattr[0]["attrs"]
            category = self.lhs_objs[0].get("option")  # None if unset

            obj = self.search_for_obj(objname)
            if not obj:
                return

            if not self.check_obj(obj):
                return

            result = []
            if "edit" in self.switches:
                # edit in the line editor
                if not (obj.access(self.caller, "control") or obj.access(self.caller, "edit")):
                    caller.msg("You don't have permission to edit %s." % obj.key)
                    return

                if len(attrs) > 1:
                    caller.msg("The Line editor can only be applied " "to one attribute at a time.")
                    return
                if not attrs:
                    caller.msg(
                        "Use `set/edit <objname>/<attr>` to define the Attribute to edit.\nTo "
                        "edit the current room description, use `set/edit here/desc` (or "
                        "use the `desc` command)."
                    )
                    return
                self.edit_handler(obj, attrs[0], caller)
                return
            if not value:
                if self.rhs is None:
                    # no = means we inspect the attribute(s)
                    if not attrs:
                        attrs = [
                            attr.key
                            for attr in obj.attributes.get(
                                category=None, return_obj=True, return_list=True
                            )
                        ]
                    for attr in attrs:
                        if not self.check_attr(obj, attr, category):
                            continue
                        result.append(self.view_attr(obj, attr, category))
                else:
                    # deleting the attribute(s)
                    if not (obj.access(self.caller, "control") or obj.access(self.caller, "edit")):
                        caller.msg("You don't have permission to edit %s." % obj.key)
                        return
                    for attr in attrs:
                        if not self.check_attr(obj, attr, category):
                            continue
                        result.append(self.rm_attr(obj, attr, category))
            else:
                # setting attribute(s). Make sure to convert to real Python type before saving.
                # add support for $dbref() and $search() in set argument
                global _ATTRFUNCPARSER
                if not _ATTRFUNCPARSER:
                    _ATTRFUNCPARSER = funcparser.FuncParser(
                        {
                            "dbref": funcparser.funcparser_callable_search,
                            "search": funcparser.funcparser_callable_search,
                        }
                    )

                if not (obj.access(self.caller, "control") or obj.access(self.caller, "edit")):
                    caller.msg("You don't have permission to edit %s." % obj.key)
                    return
                for attr in attrs:
                    if not self.check_attr(obj, attr, category):
                        continue
                    # from evennia import set_trace;set_trace()
                    parsed_value = _ATTRFUNCPARSER.parse(value, return_str=False, caller=caller)
                    if hasattr(parsed_value, "access"):
                        # if this is an object we must have the right to read it, if so,
                        # we will not convert it to a string
                        if not (
                            parsed_value.access(caller, "control")
                            or parsed_value.access(self.caller, "edit")
                        ):
                            caller.msg(
                                "You don't have permission to set " f"object with identifier '{value}'."
                            )
                            continue
                        value = parsed_value
                    else:
                        value = _convert_from_string(self, value)
                    result.append(self.set_attr(obj, attr, value, category))
            # check if anything was done
            if not result:
                caller.msg(
                    "No valid attributes were found. Usage: set obj/attr[:category] = value. Use empty value to clear."
                )
            else:
                # send feedback
                caller.msg("".join(result).strip("\n"))

    class CmdTypeclass(COMMAND_DEFAULT_CLASS):
        """
        set or change an object's typeclass

        Usage:
          typeclass[/switch] <object> [= typeclass.path]
          typeclass/prototype <object> = prototype_key

          typeclasses or typeclass/list/show [typeclass.path]
          swap - this is a shorthand for using /force/reset flags.
          update - this is a shorthand for using the /force/reload flag.

        Switch:
          show, examine - display the current typeclass of object (default) or, if
                given a typeclass path, show the docstring of that typeclass.
          update - *only* re-run at_object_creation on this object
                  meaning locks or other properties set later may remain.
          reset - clean out *all* the attributes and properties on the
                  object - basically making this a new clean object. This will also
                  reset cmdsets!
          force - change to the typeclass also if the object
                  already has a typeclass of the same name.
          list - show available typeclasses. Only typeclasses in modules actually
                 imported or used from somewhere in the code will show up here
                 (those typeclasses are still available if you know the path)
          prototype - clean and overwrite the object with the specified
                   prototype key - effectively making a whole new object.

        Example:
          type button = examples.red_button.RedButton
          type/prototype button=a red button

        If the typeclass_path is not given, the current object's typeclass is
        assumed.

        View or set an object's typeclass. If setting, the creation hooks of the
        new typeclass will be run on the object. If you have clashing properties on
        the old class, use /reset. By default you are protected from changing to a
        typeclass of the same name as the one you already have - use /force to
        override this protection.

        The given typeclass must be identified by its location using python
        dot-notation pointing to the correct module and class. If no typeclass is
        given (or a wrong typeclass is given). Errors in the path or new typeclass
        will lead to the old typeclass being kept. The location of the typeclass
        module is searched from the default typeclass directory, as defined in the
        server settings.

        """

        key = "@typeclass"
        aliases = ["@type", "@parent", "@swap", "@update", "@typeclasses"]
        switch_options = ("show", "examine", "update", "reset", "force", "list", "prototype")
        locks = "cmd:perm(typeclass) or perm(Builder)"
        help_category = "Building"

        def _generic_search(self, query, typeclass_path):

            caller = self.caller
            if typeclass_path:
                # make sure we search the right database table
                try:
                    new_typeclass = class_from_module(typeclass_path)
                except ImportError:
                    # this could be a prototype and not a typeclass at all
                    return caller.search(query)

                dbclass = new_typeclass.__dbclass__

                if caller.__dbclass__ == dbclass:
                    # object or account match
                    obj = caller.search(query)
                    if not obj:
                        return
                elif self.account and self.account.__dbclass__ == dbclass:
                    # applying account while caller is object
                    caller.msg(f"Trying to search {new_typeclass} with query '{self.lhs}'.")
                    obj = self.account.search(query)
                    if not obj:
                        return
                elif hasattr(caller, "puppet") and caller.puppet.__dbclass__ == dbclass:
                    # applying object while caller is account
                    caller.msg(f"Trying to search {new_typeclass} with query '{self.lhs}'.")
                    obj = caller.puppet.search(query)
                    if not obj:
                        return
                else:
                    # other mismatch between caller and specified typeclass
                    caller.msg(f"Trying to search {new_typeclass} with query '{self.lhs}'.")
                    obj = new_typeclass.search(query)
                    if not obj:
                        if isinstance(obj, list):
                            caller.msg(f"Could not find {new_typeclass} with query '{self.lhs}'.")
                        return
            else:
                # no rhs, use caller's typeclass
                obj = caller.search(query)
                if not obj:
                    return

            return obj

        def func(self):
            """Implements command"""

            caller = self.caller

            if "list" in self.switches or self.cmdname in ("typeclasses", "@typeclasses"):
                tclasses = get_all_typeclasses()
                contribs = [key for key in sorted(tclasses) if key.startswith("evennia.contrib")] or [
                    "<None loaded>"
                ]
                core = [
                    key for key in sorted(tclasses) if key.startswith("evennia") and key not in contribs
                ] or ["<None loaded>"]
                game = [key for key in sorted(tclasses) if not key.startswith("evennia")] or [
                    "<None loaded>"
                ]
                string = (
                    "|wCore typeclasses|n\n"
                    "    {core}\n"
                    "|wLoaded Contrib typeclasses|n\n"
                    "    {contrib}\n"
                    "|wGame-dir typeclasses|n\n"
                    "    {game}"
                ).format(
                    core="\n    ".join(core), contrib="\n    ".join(contribs), game="\n    ".join(game)
                )
                EvMore(caller, string, exit_on_lastpage=True)
                return

            if not self.args:
                caller.msg("Usage: %s <object> [= typeclass]" % self.cmdstring)
                return

            if "show" in self.switches or "examine" in self.switches:
                oquery = self.lhs
                obj = caller.search(oquery, quiet=True)
                if not obj:
                    # no object found to examine, see if it's a typeclass-path instead
                    tclasses = get_all_typeclasses()
                    matches = [
                        (key, tclass) for key, tclass in tclasses.items() if key.endswith(oquery)
                    ]
                    nmatches = len(matches)
                    if nmatches > 1:
                        caller.msg(
                            "Multiple typeclasses found matching {}:\n  {}".format(
                                oquery, "\n  ".join(tup[0] for tup in matches)
                            )
                        )
                    elif not matches:
                        caller.msg("No object or typeclass path found to match '{}'".format(oquery))
                    else:
                        # one match found
                        caller.msg(
                            "Docstring for typeclass '{}':\n{}".format(oquery, matches[0][1].__doc__)
                        )
                else:
                    # do the search again to get the error handling in case of multi-match
                    obj = caller.search(oquery)
                    if not obj:
                        return
                    caller.msg(
                        "{}'s current typeclass is '{}.{}'".format(
                            obj.name, obj.__class__.__module__, obj.__class__.__name__
                        )
                    )
                return

            obj = self._generic_search(self.lhs, self.rhs)
            if not obj:
                return

            if not hasattr(obj, "__dbclass__"):
                string = "%s is not a typed object." % obj.name
                caller.msg(string)
                return

            new_typeclass = self.rhs or obj.path

            prototype = None
            if "prototype" in self.switches:
                key = self.rhs
                prototype = protlib.search_prototype(key=key)
                if len(prototype) > 1:
                    caller.msg(
                        "More than one match for {}:\n{}".format(
                            key, "\n".join(proto.get("prototype_key", "") for proto in prototype)
                        )
                    )
                    return
                elif prototype:
                    # one match
                    prototype = prototype[0]
                else:
                    # no match
                    caller.msg("No prototype '{}' was found.".format(key))
                    return
                new_typeclass = prototype["typeclass"]
                self.switches.append("force")

            if "show" in self.switches or "examine" in self.switches:
                string = "%s's current typeclass is %s." % (obj.name, obj.__class__)
                caller.msg(string)
                return

            if self.cmdstring in ("swap", "@swap"):
                self.switches.append("force")
                self.switches.append("reset")
            elif self.cmdstring in ("update", "@update"):
                self.switches.append("force")
                self.switches.append("update")

            if not (obj.access(caller, "control") or obj.access(caller, "edit")):
                caller.msg("You are not allowed to do that.")
                return

            if not hasattr(obj, "swap_typeclass"):
                caller.msg("This object cannot have a type at all!")
                return

            is_same = obj.is_typeclass(new_typeclass, exact=True)
            if is_same and "force" not in self.switches:
                string = (
                    f"{obj.name} already has the typeclass '{new_typeclass}'. "
                    "Use /force to override."
                )
            else:
                reset = "reset" in self.switches
                update = "update" in self.switches or not reset  # default to update

                hooks = "at_object_creation" if update and not reset else "all"
                old_typeclass_path = obj.typeclass_path

                if reset:
                    answer = yield (
                        "|yNote that this will reset the object back to its typeclass' default state, "
                        "removing any custom locks/perms/attributes etc that may have been added "
                        "by an explicit create_object call. Use `update` or type/force instead in order "
                        "to keep such data. "
                        "Continue [Y]/N?|n"
                    )
                    if answer.upper() in ("N", "NO"):
                        caller.msg("Aborted.")
                        return

                # special prompt for the user in cases where we want
                # to confirm changes.
                if "prototype" in self.switches:
                    diff, _ = spawner.prototype_diff_from_object(prototype, obj)
                    txt = spawner.format_diff(diff)
                    prompt = (
                        "Applying prototype '%s' over '%s' will cause the follow changes:\n%s\n"
                        % (prototype["key"], obj.name, txt)
                    )
                    if not reset:
                        prompt += "\n|yWARNING:|n Use the /reset switch to apply the prototype over a blank state."
                    prompt += "\nAre you sure you want to apply these changes [yes]/no?"
                    answer = yield (prompt)
                    if answer and answer in ("no", "n"):
                        caller.msg("Canceled: No changes were applied.")
                        return

                # we let this raise exception if needed
                obj.swap_typeclass(
                    new_typeclass, clean_attributes=reset, clean_cmdsets=reset, run_start_hooks=hooks
                )

                if "prototype" in self.switches:
                    modified = spawner.batch_update_objects_with_prototype(
                        prototype, objects=[obj], caller=self.caller
                    )
                    prototype_success = modified > 0
                    if not prototype_success:
                        caller.msg("Prototype %s failed to apply." % prototype["key"])

                if is_same:
                    string = "%s updated its existing typeclass (%s).\n" % (obj.name, obj.path)
                else:
                    string = "%s changed typeclass from %s to %s.\n" % (
                        obj.name,
                        old_typeclass_path,
                        obj.typeclass_path,
                    )
                if update:
                    string += "Only the at_object_creation hook was run (update mode)."
                else:
                    string += "All object creation hooks were run."
                if reset:
                    string += " All old attributes where deleted before the swap."
                else:
                    string += " Attributes set before swap were not removed\n(use `swap` or `type/reset` to clear all)."
                if "prototype" in self.switches and prototype_success:
                    string += (
                        " Prototype '%s' was successfully applied over the object type."
                        % prototype["key"]
                    )

            caller.msg(string)

    class CmdWipe(ObjManipCommand):
        """
        clear all attributes from an object

        Usage:
          wipe <object>[/<attr>[/<attr>...]]

        Example:
          wipe box
          wipe box/colour

        Wipes all of an object's attributes, or optionally only those
        matching the given attribute-wildcard search string.
        """

        key = "@wipe"
        locks = "cmd:perm(wipe) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """
            inp is the dict produced in ObjManipCommand.parse()
            """

            caller = self.caller

            if not self.args:
                caller.msg("Usage: wipe <object>[/<attr>/<attr>...]")
                return

            # get the attributes set by our custom parser
            objname = self.lhs_objattr[0]["name"]
            attrs = self.lhs_objattr[0]["attrs"]

            obj = caller.search(objname)
            if not obj:
                return
            if not (obj.access(caller, "control") or obj.access(caller, "edit")):
                caller.msg("You are not allowed to do that.")
                return
            if not attrs:
                # wipe everything
                obj.attributes.clear()
                string = "Wiped all attributes on %s." % obj.name
            else:
                for attrname in attrs:
                    obj.attributes.remove(attrname)
                string = "Wiped attributes %s on %s."
                string = string % (",".join(attrs), obj.name)
            caller.msg(string)

    class CmdLock(ObjManipCommand):
        """
        assign a lock definition to an object

        Usage:
          lock <object or *account>[ = <lockstring>]
          or
          lock[/switch] <object or *account>/<access_type>

        Switch:
          del - delete given access type
          view - view lock associated with given access type (default)

        If no lockstring is given, shows all locks on
        object.

        Lockstring is of the form
           access_type:[NOT] func1(args)[ AND|OR][ NOT] func2(args) ...]
        Where func1, func2 ... valid lockfuncs with or without arguments.
        Separator expressions need not be capitalized.

        For example:
           'get: id(25) or perm(Admin)'
        The 'get' lock access_type is checked e.g. by the 'get' command.
        An object locked with this example lock will only be possible to pick up
        by Admins or by an object with id=25.

        You can add several access_types after one another by separating
        them by ';', i.e:
           'get:id(25); delete:perm(Builder)'
        """

        key = "@lock"
        aliases = ["@locks"]
        locks = "cmd: perm(locks) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """Sets up the command"""

            caller = self.caller
            if not self.args:
                string = (
                    "Usage: lock <object>[ = <lockstring>] or lock[/switch] " "<object>/<access_type>"
                )
                caller.msg(string)
                return

            if "/" in self.lhs:
                # call of the form lock obj/access_type
                objname, access_type = [p.strip() for p in self.lhs.split("/", 1)]
                obj = None
                if objname.startswith("*"):
                    obj = caller.search_account(objname.lstrip("*"))
                if not obj:
                    obj = caller.search(objname)
                    if not obj:
                        return
                has_control_access = obj.access(caller, "control")
                if access_type == "control" and not has_control_access:
                    # only allow to change 'control' access if you have 'control' access already
                    caller.msg("You need 'control' access to change this type of lock.")
                    return

                if not (has_control_access or obj.access(caller, "edit")):
                    caller.msg("You are not allowed to do that.")
                    return

                lockdef = obj.locks.get(access_type)

                if lockdef:
                    if "del" in self.switches:
                        obj.locks.delete(access_type)
                        string = "deleted lock %s" % lockdef
                    else:
                        string = lockdef
                else:
                    string = "%s has no lock of access type '%s'." % (obj, access_type)
                caller.msg(string)
                return

            if self.rhs:
                # we have a = separator, so we are assigning a new lock
                if self.switches:
                    swi = ", ".join(self.switches)
                    caller.msg(
                        "Switch(es) |w%s|n can not be used with a "
                        "lock assignment. Use e.g. "
                        "|wlock/del objname/locktype|n instead." % swi
                    )
                    return

                objname, lockdef = self.lhs, self.rhs
                obj = None
                if objname.startswith("*"):
                    obj = caller.search_account(objname.lstrip("*"))
                if not obj:
                    obj = caller.search(objname)
                    if not obj:
                        return
                if not (obj.access(caller, "control") or obj.access(caller, "edit")):
                    caller.msg("You are not allowed to do that.")
                    return
                ok = False
                lockdef = re.sub(r"\'|\"", "", lockdef)
                try:
                    ok = obj.locks.add(lockdef)
                except LockException as e:
                    caller.msg(str(e))
                if "cmd" in lockdef.lower() and inherits_from(
                    obj, "evennia.objects.objects.DefaultExit"
                ):
                    # special fix to update Exits since "cmd"-type locks won't
                    # update on them unless their cmdsets are rebuilt.
                    obj.at_init()
                if ok:
                    caller.msg("Added lock '%s' to %s." % (lockdef, obj))
                return

            # if we get here, we are just viewing all locks on obj
            obj = None
            if self.lhs.startswith("*"):
                obj = caller.search_account(self.lhs.lstrip("*"))
            if not obj:
                obj = caller.search(self.lhs)
            if not obj:
                return
            if not (obj.access(caller, "control") or obj.access(caller, "edit")):
                caller.msg("You are not allowed to do that.")
                return
            caller.msg("\n".join(obj.locks.all()))

    class CmdExamine(ObjManipCommand):
        """
        get detailed information about an object

        Usage:
          examine [<object>[/attrname]]
          examine [*<account>[/attrname]]

        Switch:
          account - examine an Account (same as adding *)
          object - examine an Object (useful when OOC)
          script - examine a Script
          channel - examine a Channel

        The examine command shows detailed game info about an
        object and optionally a specific attribute on it.
        If object is not specified, the current location is examined.

        Append a * before the search string to examine an account.

        """

        key = "@examine"
        aliases = ["@ex", "@exam"]
        locks = "cmd:perm(examine) or perm(Builder)"
        help_category = "Building"
        arg_regex = r"(/\w+?(\s|$))|\s|$"
        switch_options = ["account", "object", "script", "channel"]

        object_type = "object"

        detail_color = "|c"
        header_color = "|w"
        quell_color = "|r"
        separator = "-"

        def msg(self, text):
            """
            Central point for sending messages to the caller. This tags
            the message as 'examine' for eventual custom markup in the client.

            Attributes:
                text (str): The text to send.

            """
            self.caller.msg(text=(text, {"type": "examine"}))

        def format_key(self, obj):
            return f"{obj.name} ({obj.dbref})"

        def format_aliases(self, obj):
            if hasattr(obj, "aliases") and obj.aliases.all():
                return ", ".join(utils.make_iter(str(obj.aliases)))

        def format_typeclass(self, obj):
            if hasattr(obj, "typeclass_path"):
                return f"{obj.typename} ({obj.typeclass_path})"

        def format_sessions(self, obj):
            if hasattr(obj, "sessions"):
                sessions = obj.sessions.all()
                if sessions:
                    return ", ".join(f"#{sess.sessid}" for sess in obj.sessions.all())

        def format_email(self, obj):
            if hasattr(obj, "email") and obj.email:
                return f"{self.detail_color}{obj.email}|n"

        def format_account_key(self, account):
            return f"{self.detail_color}{account.name}|n ({account.dbref})"

        def format_account_typeclass(self, account):
            return f"{account.typename} ({account.typeclass_path})"

        def format_account_permissions(self, account):
            perms = account.permissions.all()
            if account.is_superuser:
                perms = ["<Superuser>"]
            elif not perms:
                perms = ["<None>"]
            perms = ", ".join(perms)
            if account.attributes.has("_quell"):
                perms += f" {self.quell_color}(quelled)|n"
            return perms

        def format_location(self, obj):
            if hasattr(obj, "location") and obj.location:
                return f"{obj.location.key} (#{obj.location.id})"

        def format_home(self, obj):
            if hasattr(obj, "home") and obj.home:
                return f"{obj.home.key} (#{obj.home.id})"

        def format_destination(self, obj):
            if hasattr(obj, "destination") and obj.destination:
                return f"{obj.destination.key} (#{obj.destination.id})"

        def format_permissions(self, obj):
            perms = obj.permissions.all()
            if perms:
                perms_string = ", ".join(perms)
                if obj.is_superuser:
                    perms_string += " <Superuser>"
                return perms_string

        def format_locks(self, obj):
            locks = str(obj.locks)
            if locks:
                return utils.fill("; ".join([lock for lock in locks.split(";")]), indent=2)
            return "Default"

        def format_scripts(self, obj):
            if hasattr(obj, "scripts") and hasattr(obj.scripts, "all") and obj.scripts.all():
                return f"{obj.scripts}"

        def format_single_tag(self, tag):
            if tag.db_category:
                return f"{tag.db_key}[{tag.db_category}]"
            else:
                return f"{tag.db_key}"

        def format_tags(self, obj):
            if hasattr(obj, "tags"):
                tags = sorted(obj.tags.all(return_objs=True))
                if tags:
                    formatted_tags = [self.format_single_tag(tag) for tag in tags]
                    return utils.fill(", ".join(formatted_tags), indent=2)

        def format_single_cmdset_options(self, cmdset):
            def _truefalse(string, value):
                if value is None:
                    return ""
                if value:
                    return f"{string}: T"
                return f"{string}: F"

            txt = ", ".join(
                _truefalse(opt, getattr(cmdset, opt))
                for opt in ("no_exits", "no_objs", "no_channels", "duplicates")
                if getattr(cmdset, opt) is not None
            )
            return ", " + txt if txt else ""

        def format_single_cmdset(self, cmdset):
            options = self.format_single_cmdset_options(cmdset)
            return f"{cmdset.path} [{cmdset.key}] ({cmdset.mergetype}, prio {cmdset.priority}{options})"

        def format_stored_cmdsets(self, obj):
            if hasattr(obj, "cmdset"):
                stored_cmdset_strings = []
                stored_cmdsets = sorted(obj.cmdset.all(), key=lambda x: x.priority, reverse=True)
                for cmdset in stored_cmdsets:
                    if cmdset.key != "_EMPTY_CMDSET":
                        stored_cmdset_strings.append(self.format_single_cmdset(cmdset))
                return "\n  " + "\n  ".join(stored_cmdset_strings)

        def format_merged_cmdsets(self, obj, current_cmdset):
            if not hasattr(obj, "cmdset"):
                return None

            all_cmdsets = [(cmdset.key, cmdset) for cmdset in current_cmdset.merged_from]
            # we always at least try to add account- and session sets since these are ignored
            # if we merge on the object level.
            if hasattr(obj, "account") and obj.account:
                # get Attribute-cmdsets if they exist
                all_cmdsets.extend([(cmdset.key, cmdset) for cmdset in obj.account.cmdset.all()])
                if obj.sessions.count():
                    # if there are more sessions than one on objects it's because of multisession mode
                    # we only show the first session's cmdset here (it is -in principle- possible
                    # that different sessions have different cmdsets but for admins who want such
                    # madness it is better that they overload with their own CmdExamine to handle it).
                    all_cmdsets.extend(
                        [(cmdset.key, cmdset) for cmdset in obj.account.sessions.all()[0].cmdset.all()]
                    )
            else:
                try:
                    # we have to protect this since many objects don't have sessions.
                    all_cmdsets.extend(
                        [
                            (cmdset.key, cmdset)
                            for cmdset in obj.get_session(obj.sessions.get()).cmdset.all()
                        ]
                    )
                except (TypeError, AttributeError):
                    # an error means we are merging an object without a session
                    pass
            all_cmdsets = [cmdset for cmdset in dict(all_cmdsets).values()]
            all_cmdsets.sort(key=lambda x: x.priority, reverse=True)

            merged_cmdset_strings = []
            for cmdset in all_cmdsets:
                if cmdset.key != "_EMPTY_CMDSET":
                    merged_cmdset_strings.append(self.format_single_cmdset(cmdset))
            return "\n  " + "\n  ".join(merged_cmdset_strings)

        def format_current_cmds(self, obj, current_cmdset):
            current_commands = sorted([cmd.key for cmd in current_cmdset if cmd.access(obj, "cmd")])
            return "\n" + utils.fill(", ".join(current_commands), indent=2)

        def _get_attribute_value_type(self, attrvalue):
            typ = ""
            if not isinstance(attrvalue, str):
                try:
                    name = attrvalue.__class__.__name__
                except AttributeError:
                    try:
                        name = attrvalue.__name__
                    except AttributeError:
                        name = attrvalue
                if str(name).startswith("_Saver"):
                    try:
                        typ = str(type(deserialize(attrvalue)))
                    except Exception:
                        typ = str(type(deserialize(attrvalue)))
                else:
                    typ = str(type(attrvalue))
            return typ

        def format_single_attribute_detail(self, obj, attr):
            global _FUNCPARSER
            if not _FUNCPARSER:
                _FUNCPARSER = funcparser.FuncParser(settings.FUNCPARSER_OUTGOING_MESSAGES_MODULES)

            key, category, value = attr.db_key, attr.db_category, attr.value
            typ = self._get_attribute_value_type(value)
            typ = f" |B[type: {typ}]|n" if typ else ""
            value = utils.to_str(value)
            value = _FUNCPARSER.parse(ansi_raw(value), escape=True)
            return (
                f"Attribute {obj.name}/{self.header_color}{key}|n "
                f"[category={category}]{typ}:\n\n{value}"
            )

        def format_single_attribute(self, attr):
            global _FUNCPARSER
            if not _FUNCPARSER:
                _FUNCPARSER = funcparser.FuncParser(settings.FUNCPARSER_OUTGOING_MESSAGES_MODULES)

            key, category, value = attr.db_key, attr.db_category, attr.value
            typ = self._get_attribute_value_type(value)
            typ = f" |B[type: {typ}]|n" if typ else ""
            value = utils.to_str(value)
            value = _FUNCPARSER.parse(ansi_raw(value), escape=True)
            value = utils.crop(value)
            if category:
                return f"{self.header_color}{key}|n[{category}]={value}{typ}"
            else:
                return f"{self.header_color}{key}|n={value}{typ}"

        def format_attributes(self, obj):
            output = "\n  " + "\n  ".join(
                sorted(self.format_single_attribute(attr) for attr in obj.db_attributes.all())
            )
            if output.strip():
                # we don't want just an empty line
                return output

        def format_nattributes(self, obj):
            try:
                ndb_attr = obj.nattributes.all()
            except Exception:
                return

            if ndb_attr and ndb_attr[0]:
                return "\n  " + "\n  ".join(
                    sorted(self.format_single_attribute(attr) for attr in ndb_attr)
                )

        def format_exits(self, obj):
            if hasattr(obj, "exits"):
                exits = ", ".join(f"{exit.name}({exit.dbref})" for exit in obj.exits)
                return exits if exits else None

        def format_chars(self, obj):
            if hasattr(obj, "contents"):
                chars = ", ".join(f"{obj.name}({obj.dbref})" for obj in obj.contents if obj.account)
                return chars if chars else None

        def format_things(self, obj):
            if hasattr(obj, "contents"):
                things = ", ".join(
                    f"{obj.name}({obj.dbref})"
                    for obj in obj.contents
                    if not obj.account and not obj.destination
                )
                return things if things else None

        def format_script_desc(self, obj):
            if hasattr(obj, "db_desc") and obj.db_desc:
                return crop(obj.db_desc, 20)

        def format_script_is_persistent(self, obj):
            if hasattr(obj, "db_persistent"):
                return "T" if obj.db_persistent else "F"

        def format_script_timer_data(self, obj):
            if hasattr(obj, "db_interval") and obj.db_interval > 0:
                start_delay = "T" if obj.db_start_delay else "F"
                next_repeat = obj.time_until_next_repeat()
                active = "|grunning|n" if obj.db_is_active and next_repeat else "|rinactive|n"
                interval = obj.db_interval
                next_repeat = "N/A" if next_repeat is None else f"{next_repeat}s"
                repeats = ""
                if obj.db_repeats:
                    remaining_repeats = obj.remaining_repeats()
                    remaining_repeats = 0 if remaining_repeats is None else remaining_repeats
                    repeats = f" - {remaining_repeats}/{obj.db_repeats} remain"
                return (
                    f"{active} - interval: {interval}s "
                    f"(next: {next_repeat}{repeats}, start_delay: {start_delay})"
                )

        def format_channel_sub_totals(self, obj):
            if hasattr(obj, "db_account_subscriptions"):
                account_subs = obj.db_account_subscriptions.all()
                object_subs = obj.db_object_subscriptions.all()
                online = len(obj.subscriptions.online())
                ntotal = account_subs.count() + object_subs.count()
                return f"{ntotal} ({online} online)"

        def format_channel_account_subs(self, obj):
            if hasattr(obj, "db_account_subscriptions"):
                account_subs = obj.db_account_subscriptions.all()
                if account_subs:
                    return "\n  " + "\n  ".join(
                        format_grid([sub.key for sub in account_subs], sep=" ", width=_DEFAULT_WIDTH)
                    )

        def format_channel_object_subs(self, obj):
            if hasattr(obj, "db_object_subscriptions"):
                object_subs = obj.db_object_subscriptions.all()
                if object_subs:
                    return "\n  " + "\n  ".join(
                        format_grid([sub.key for sub in object_subs], sep=" ", width=_DEFAULT_WIDTH)
                    )

        def get_formatted_obj_data(self, obj, current_cmdset):
            """
            Calls all other `format_*` methods.

            """
            objdata = {}
            objdata["Name/key"] = self.format_key(obj)
            objdata["Aliases"] = self.format_aliases(obj)
            objdata["Typeclass"] = self.format_typeclass(obj)
            objdata["Sessions"] = self.format_sessions(obj)
            objdata["Email"] = self.format_email(obj)
            if hasattr(obj, "has_account") and obj.has_account:
                objdata["Account"] = self.format_account_key(obj.account)
                objdata["  Account Typeclass"] = self.format_account_typeclass(obj.account)
                objdata["  Account Permissions"] = self.format_account_permissions(obj.account)
            objdata["Location"] = self.format_location(obj)
            objdata["Home"] = self.format_home(obj)
            objdata["Destination"] = self.format_destination(obj)
            objdata["Permissions"] = self.format_permissions(obj)
            objdata["Locks"] = self.format_locks(obj)
            if current_cmdset and not (
                len(obj.cmdset.all()) == 1 and obj.cmdset.current.key == "_EMPTY_CMDSET"
            ):
                objdata["Stored Cmdset(s)"] = self.format_stored_cmdsets(obj)
                objdata["Merged Cmdset(s)"] = self.format_merged_cmdsets(obj, current_cmdset)
                objdata[
                    f"Commands available to {obj.key} (result of Merged Cmdset(s))"
                ] = self.format_current_cmds(obj, current_cmdset)
            if self.object_type == "script":
                objdata["Description"] = self.format_script_desc(obj)
                objdata["Persistent"] = self.format_script_is_persistent(obj)
                objdata["Script Repeat"] = self.format_script_timer_data(obj)
            objdata["Scripts"] = self.format_scripts(obj)
            objdata["Tags"] = self.format_tags(obj)
            objdata["Persistent Attributes"] = self.format_attributes(obj)
            objdata["Non-Persistent Attributes"] = self.format_nattributes(obj)
            objdata["Exits"] = self.format_exits(obj)
            objdata["Characters"] = self.format_chars(obj)
            objdata["Content"] = self.format_things(obj)
            if self.object_type == "channel":
                objdata["Subscription Totals"] = self.format_channel_sub_totals(obj)
                objdata["Account Subscriptions"] = self.format_channel_account_subs(obj)
                objdata["Object Subscriptions"] = self.format_channel_object_subs(obj)

            return objdata

        def format_output(self, obj, current_cmdset):
            """
            Formats the full examine page return.

            """
            objdata = self.get_formatted_obj_data(obj, current_cmdset)

            # format output
            main_str = []
            max_width = -1
            for header, block in objdata.items():
                if block is not None:
                    blockstr = f"{self.header_color}{header}|n: {block}"
                    max_width = max(max_width, max(display_len(line) for line in blockstr.split("\n")))
                    main_str.append(blockstr)
            main_str = "\n".join(main_str)

            max_width = max(0, min(self.client_width(), max_width))
            sep = self.separator * max_width

            return f"{sep}\n{main_str}\n{sep}"

        def _search_by_object_type(self, obj_name, objtype):
            """
            Route to different search functions depending on the object type being
            examined. This also handles error reporting for multimatches/no matches.

            Args:
                obj_name (str): The search query.
                objtype (str): One of 'object', 'account', 'script' or 'channel'.
            Returns:
                any: `None` if no match or multimatch, otherwise a single result.

            """
            obj = None

            if objtype == "object":
                obj = self.caller.search(obj_name)
            elif objtype == "account":
                try:
                    obj = self.caller.search_account(obj_name.lstrip("*"))
                except AttributeError:
                    # this means we are calling examine from an account object
                    obj = self.caller.search(
                        obj_name.lstrip("*"), search_object="object" in self.switches
                    )
            else:
                obj = getattr(search, f"search_{objtype}")(obj_name)
                if not obj:
                    self.caller.msg(f"No {objtype} found with key {obj_name}.")
                    obj = None
                elif len(obj) > 1:
                    err = "Multiple {objtype} found with key {obj_name}:\n{matches}"
                    self.caller.msg(
                        err.format(
                            obj_name=obj_name, matches=", ".join(f"{ob.key}(#{ob.id})" for ob in obj)
                        )
                    )
                    obj = None
                else:
                    obj = obj[0]
            return obj

        def parse(self):
            super().parse()

            self.examine_objs = []

            if not self.args:
                # If no arguments are provided, examine the invoker's location.
                if hasattr(self.caller, "location"):
                    self.examine_objs.append((self.caller.location, None))
                else:
                    self.msg("You need to supply a target to examine.")
                    raise InterruptCommand
            else:
                for objdef in self.lhs_objattr:
                    # note that we check the objtype for every repeat; this will always
                    # be the same result, but it makes for a cleaner code and multi-examine
                    # is not so common anyway.

                    obj = None
                    obj_name = objdef["name"]  # name
                    obj_attrs = objdef["attrs"]  # /attrs

                    # identify object type, in prio account - script - channel
                    object_type = "object"
                    if (
                        utils.inherits_from(self.caller, "evennia.accounts.accounts.DefaultAccount")
                        or "account" in self.switches
                        or obj_name.startswith("*")
                    ):
                        object_type = "account"
                    elif "script" in self.switches:
                        object_type = "script"
                    elif "channel" in self.switches:
                        object_type = "channel"

                    self.object_type = object_type
                    obj = self._search_by_object_type(obj_name, object_type)

                    if obj:
                        self.examine_objs.append((obj, obj_attrs))

        def func(self):
            """Process command"""
            for obj, obj_attrs in self.examine_objs:
                # these are parsed out in .parse already

                if not obj.access(self.caller, "examine"):
                    # If we don't have special info access, just look
                    # at the object instead.
                    self.msg(self.caller.at_look(obj))
                    continue

                if obj_attrs:
                    # we are only interested in specific attributes
                    attrs = [attr for attr in obj.db_attributes.all() if attr.db_key in obj_attrs]
                    if not attrs:
                        self.msg(f"No attributes found on {obj.name}.")
                    else:
                        out_strings = []
                        for attr in attrs:
                            out_strings.append(self.format_single_attribute_detail(obj, attr))
                        out_str = "\n".join(out_strings)
                        max_width = max(display_len(line) for line in out_strings)
                        max_width = max(0, min(max_width, self.client_width()))
                        sep = self.separator * max_width
                        self.msg(f"{sep}\n{out_str}")
                    return

                # examine the obj itself

                if self.object_type in ("object", "account"):
                    # for objects and accounts we need to set up an asynchronous
                    # fetch of the cmdset and not proceed with the examine display
                    # until the fetch is complete
                    session = None
                    if obj.sessions.count():
                        mergemode = "session"
                        session = obj.sessions.get()[0]
                    elif self.object_type == "account":
                        mergemode = "account"
                    else:
                        mergemode = "object"

                    account = None
                    objct = None
                    if self.object_type == "account":
                        account = obj
                    else:
                        account = obj.account
                        objct = obj

                    # this is usually handled when a command runs, but when we examine
                    # we may have leftover inherited cmdsets directly after a move etc.
                    obj.cmdset.update()
                    # using callback to print results whenever function returns.

                    def _get_cmdset_callback(current_cmdset):
                        self.msg(self.format_output(obj, current_cmdset).strip())

                    get_and_merge_cmdsets(
                        obj, session, account, objct, mergemode, self.raw_string
                    ).addCallback(_get_cmdset_callback)

                else:
                    # for objects without cmdsets we can proceed to examine immediately
                    self.msg(self.format_output(obj, None).strip())

    class CmdFind(COMMAND_DEFAULT_CLASS):
        """
        search the database for objects

        Usage:
          find[/switches] <name or dbref or *account> [= dbrefmin[-dbrefmax]]
          locate - this is a shorthand for using the /loc switch.

        Switches:
          room       - only look for rooms (location=None)
          exit       - only look for exits (destination!=None)
          char       - only look for characters (BASE_CHARACTER_TYPECLASS)
          exact      - only exact matches are returned.
          loc        - display object location if exists and match has one result
          startswith - search for names starting with the string, rather than containing

        Searches the database for an object of a particular name or exact #dbref.
        Use *accountname to search for an account. The switches allows for
        limiting object matches to certain game entities. Dbrefmin and dbrefmax
        limits matches to within the given dbrefs range, or above/below if only
        one is given.
        """

        key = "@find"
        aliases = ["@search", "@locate"]
        switch_options = ("room", "exit", "char", "exact", "loc", "startswith")
        locks = "cmd:perm(find) or perm(Builder)"
        help_category = "Building"

        def func(self):
            """Search functionality"""
            caller = self.caller
            switches = self.switches

            if not self.args or (not self.lhs and not self.rhs):
                caller.msg("Usage: find <string> [= low [-high]]")
                return

            if "locate" in self.cmdstring:  # Use option /loc as a default for locate command alias
                switches.append("loc")

            searchstring = self.lhs

            try:
                # Try grabbing the actual min/max id values by database aggregation
                qs = ObjectDB.objects.values("id").aggregate(low=Min("id"), high=Max("id"))
                low, high = sorted(qs.values())
                if not (low and high):
                    raise ValueError(
                        f"{self.__class__.__name__}: Min and max ID not returned by aggregation; falling back to queryset slicing."
                    )
            except Exception as e:
                logger.log_trace(e)
                # If that doesn't work for some reason (empty DB?), guess the lower
                # bound and do a less-efficient query to find the upper.
                low, high = 1, ObjectDB.objects.all().order_by("-id").first().id

            if self.rhs:
                try:
                    # Check that rhs is either a valid dbref or dbref range
                    bounds = tuple(
                        sorted(dbref(x, False) for x in re.split("[-\s]+", self.rhs.strip()))
                    )

                    # dbref() will return either a valid int or None
                    assert bounds
                    # None should not exist in the bounds list
                    assert None not in bounds

                    low = bounds[0]
                    if len(bounds) > 1:
                        high = bounds[-1]

                except AssertionError:
                    caller.msg("Invalid dbref range provided (not a number).")
                    return
                except IndexError as e:
                    logger.log_err(
                        f"{self.__class__.__name__}: Error parsing upper and lower bounds of query."
                    )
                    logger.log_trace(e)

            low = min(low, high)
            high = max(low, high)

            is_dbref = utils.dbref(searchstring)
            is_account = searchstring.startswith("*")

            restrictions = ""
            if self.switches:
                restrictions = ", %s" % (", ".join(self.switches))

            if is_dbref or is_account:
                if is_dbref:
                    # a dbref search
                    result = caller.search(searchstring, global_search=True, quiet=True)
                    string = "|wExact dbref match|n(#%i-#%i%s):" % (low, high, restrictions)
                else:
                    # an account search
                    searchstring = searchstring.lstrip("*")
                    result = caller.search_account(searchstring, quiet=True)
                    string = "|wMatch|n(#%i-#%i%s):" % (low, high, restrictions)

                if "room" in switches:
                    result = result if inherits_from(result, ROOM_TYPECLASS) else None
                if "exit" in switches:
                    result = result if inherits_from(result, EXIT_TYPECLASS) else None
                if "char" in switches:
                    result = result if inherits_from(result, CHAR_TYPECLASS) else None

                if not result:
                    string += "\n   |RNo match found.|n"
                elif not low <= int(result[0].id) <= high:
                    string += "\n   |RNo match found for '%s' in #dbref interval.|n" % searchstring
                else:
                    result = result[0]
                    string += "\n|g   %s - %s|n" % (result.get_display_name(caller), result.path)
                    if "loc" in self.switches and not is_account and result.location:
                        string += " (|wlocation|n: |g{}|n)".format(
                            result.location.get_display_name(caller)
                        )
            else:
                # Not an account/dbref search but a wider search; build a queryset.
                # Searches for key and aliases
                if "exact" in switches:
                    keyquery = Q(db_key__iexact=searchstring, id__gte=low, id__lte=high)
                    aliasquery = Q(
                        db_tags__db_key__iexact=searchstring,
                        db_tags__db_tagtype__iexact="alias",
                        id__gte=low,
                        id__lte=high,
                    )
                elif "startswith" in switches:
                    keyquery = Q(db_key__istartswith=searchstring, id__gte=low, id__lte=high)
                    aliasquery = Q(
                        db_tags__db_key__istartswith=searchstring,
                        db_tags__db_tagtype__iexact="alias",
                        id__gte=low,
                        id__lte=high,
                    )
                else:
                    keyquery = Q(db_key__icontains=searchstring, id__gte=low, id__lte=high)
                    aliasquery = Q(
                        db_tags__db_key__icontains=searchstring,
                        db_tags__db_tagtype__iexact="alias",
                        id__gte=low,
                        id__lte=high,
                    )

                # Keep the initial queryset handy for later reuse
                result_qs = ObjectDB.objects.filter(keyquery | aliasquery).distinct()
                nresults = result_qs.count()

                # Use iterator to minimize memory ballooning on large result sets
                results = result_qs.iterator()

                # Check and see if type filtering was requested; skip it if not
                if any(x in switches for x in ("room", "exit", "char")):
                    obj_ids = set()
                    for obj in results:
                        if (
                            ("room" in switches and inherits_from(obj, ROOM_TYPECLASS))
                            or ("exit" in switches and inherits_from(obj, EXIT_TYPECLASS))
                            or ("char" in switches and inherits_from(obj, CHAR_TYPECLASS))
                        ):
                            obj_ids.add(obj.id)

                    # Filter previous queryset instead of requesting another
                    filtered_qs = result_qs.filter(id__in=obj_ids).distinct()
                    nresults = filtered_qs.count()

                    # Use iterator again to minimize memory ballooning
                    results = filtered_qs.iterator()

                # still results after type filtering?
                if nresults:
                    if nresults > 1:
                        header = f"{nresults} Matches"
                    else:
                        header = "One Match"

                    string = f"|w{header}|n(#{low}-#{high}{restrictions}):"
                    res = None
                    for res in results:
                        string += f"\n   |g{res.get_display_name(caller)} - {res.path}|n"
                    if (
                        "loc" in self.switches
                        and nresults == 1
                        and res
                        and getattr(res, "location", None)
                    ):
                        string += f" (|wlocation|n: |g{res.location.get_display_name(caller)}|n)"
                else:
                    string = f"|wNo Matches|n(#{low}-#{high}{restrictions}):"
                    string += f"\n   |RNo matches found for '{searchstring}'|n"

            # send result
            caller.msg(string.strip())

    class ScriptEvMore(EvMore):
        """
        Listing 1000+ Scripts can be very slow and memory-consuming. So
        we use this custom EvMore child to build en EvTable only for
        each page of the list.

        """

        def init_pages(self, scripts):
            """Prepare the script list pagination"""
            script_pages = Paginator(scripts, max(1, int(self.height / 2)))
            super().init_pages(script_pages)

        def page_formatter(self, scripts):
            """Takes a page of scripts and formats the output
            into an EvTable."""

            if not scripts:
                return "<No scripts>"

            table = EvTable(
                "|wdbref|n",
                "|wobj|n",
                "|wkey|n",
                "|wintval|n",
                "|wnext|n",
                "|wrept|n",
                "|wtypeclass|n",
                "|wdesc|n",
                align="r",
                border="tablecols",
                width=self.width,
            )

            for script in scripts:

                nextrep = script.time_until_next_repeat()
                if nextrep is None:
                    nextrep = script.db._paused_time
                    nextrep = f"PAUSED {int(nextrep)}s" if nextrep else "--"
                else:
                    nextrep = f"{nextrep}s"

                maxrepeat = script.repeats
                remaining = script.remaining_repeats() or 0
                if maxrepeat:
                    rept = "%i/%i" % (maxrepeat - remaining, maxrepeat)
                else:
                    rept = "-/-"

                table.add_row(
                    f"#{script.id}",
                    f"{script.obj.key}({script.obj.dbref})"
                    if (hasattr(script, "obj") and script.obj)
                    else "<Global>",
                    script.key,
                    script.interval if script.interval > 0 else "--",
                    nextrep,
                    rept,
                    script.typeclass_path.rsplit(".", 1)[-1],
                    crop(script.desc, width=20),
                )

            return str(table)

    class CmdScripts(COMMAND_DEFAULT_CLASS):
        """
        List and manage all running scripts. Allows for creating new global
        scripts.

        Usage:
          script[/switches] [script-#dbref, key, script.path or <obj>]
          script[/start||stop] <obj> = <script.path or script-key>

        Switches:
          start - start/unpause an existing script's timer.
          stop - stops an existing script's timer
          pause - pause a script's timer
          delete - deletes script. This will also stop the timer as needed

        Examples:
            script                         - list scripts
            script myobj                   - list all scripts on object
            script foo.bar.Script          - create a new global Script
            script scriptname              - examine named existing global script
            script myobj = foo.bar.Script  - create and assign script to object
            script/stop myobj = scriptname - stop script on object
            script/pause foo.Bar.Script    - pause global script
            script/delete myobj            - delete ALL scripts on object
            script/delete #dbref[-#dbref]  - delete script or range by dbref

        When given with an `<obj>` as left-hand-side, this creates and
        assigns a new script to that object. Without an `<obj>`, this
        manages and inspects global scripts

        If no switches are given, this command just views all active
        scripts. The argument can be either an object, at which point it
        will be searched for all scripts defined on it, or a script name
        or #dbref. For using the /stop switch, a unique script #dbref is
        required since whole classes of scripts often have the same name.

        Use the `script` build-level command for managing scripts attached to
        objects.

        """

        key = "@scripts"
        aliases = ["@script"]
        switch_options = ("create", "start", "stop", "pause", "delete")
        locks = "cmd:perm(scripts) or perm(Builder)"
        help_category = "System"

        excluded_typeclass_paths = ["evennia.prototypes.prototypes.DbPrototype"]

        switch_mapping = {
            "create": "|gCreated|n",
            "start": "|gStarted|n",
            "stop": "|RStopped|n",
            "pause": "|Paused|n",
            "delete": "|rDeleted|n",
        }

        def _search_script(self, args):
            # test first if this is a script match
            scripts = ScriptDB.objects.get_all_scripts(key=args)
            if scripts:
                return scripts
            # try typeclass path
            scripts = ScriptDB.objects.filter(db_typeclass_path__iendswith=args)
            if scripts:
                return scripts
            if "-" in args:
                # may be a dbref-range
                val1, val2 = (dbref(part.strip()) for part in args.split("-", 1))
                if val1 and val2:
                    scripts = ScriptDB.objects.filter(id__in=(range(val1, val2 + 1)))
                    if scripts:
                        return scripts

        def func(self):
            """implement method"""

            caller = self.caller

            if not self.args:
                # show all scripts
                scripts = ScriptDB.objects.all()
                if not scripts:
                    caller.msg("No scripts found.")
                    return
                ScriptEvMore(caller, scripts.order_by("id"), session=self.session)
                return

            # find script or object to operate on
            scripts, obj = None, None
            if self.rhs:
                obj_query = self.lhs
                script_query = self.rhs
            else:
                obj_query = script_query = self.args

            scripts = self._search_script(script_query)
            objects = caller.search(obj_query, quiet=True)
            obj = objects[0] if objects else None

            if not self.switches:
                # creation / view mode
                if obj:
                    # we have an object
                    if self.rhs:
                        # creation mode
                        if obj.scripts.add(self.rhs, autostart=True):
                            caller.msg(
                                f"Script |w{self.rhs}|n successfully added and "
                                f"started on {obj.get_display_name(caller)}."
                            )
                        else:
                            caller.msg(
                                f"Script {self.rhs} could not be added and/or started "
                                f"on {obj.get_display_name(caller)} (or it started and "
                                "immediately shut down)."
                            )
                    else:
                        # just show all scripts on object
                        scripts = ScriptDB.objects.filter(db_obj=obj)
                        if scripts:
                            ScriptEvMore(caller, scripts.order_by("id"), session=self.session)
                        else:
                            caller.msg(f"No scripts defined on {obj}")

                elif scripts:
                    # show found script(s)
                    ScriptEvMore(caller, scripts.order_by("id"), session=self.session)

                else:
                    # create global script
                    try:
                        new_script = create.create_script(self.args)
                    except ImportError:
                        logger.log_trace()
                        new_script = None

                    if new_script:
                        caller.msg(
                            f"Global Script Created - "
                            f"{new_script.key} ({new_script.typeclass_path})"
                        )
                        ScriptEvMore(caller, [new_script], session=self.session)
                    else:
                        caller.msg(
                            f"Global Script |rNOT|n Created |r(see log)|n - " f"arguments: {self.args}"
                        )

            elif scripts or obj:
                # modification switches - must operate on existing scripts

                if not scripts:
                    scripts = ScriptDB.objects.filter(db_obj=obj)

                if scripts.count() > 1:
                    ret = yield (
                        f"Multiple scripts found: {scripts}. Are you sure you want to "
                        "operate on all of them? [Y]/N? "
                    )
                    if ret.lower() in ("n", "no"):
                        caller.msg("Aborted.")
                        return

                for script in scripts:
                    script_key = script.key
                    script_typeclass_path = script.typeclass_path
                    scripttype = f"Script on {obj}" if obj else "Global Script"

                    for switch in self.switches:
                        verb = self.switch_mapping[switch]
                        msgs = []
                        try:
                            getattr(script, switch)()
                        except Exception:
                            logger.log_trace()
                            msgs.append(
                                f"{scripttype} |rNOT|n {verb} |r(see log)|n - "
                                f"{script_key} ({script_typeclass_path})|n"
                            )
                        else:
                            msgs.append(
                                f"{scripttype} {verb} - " f"{script_key} ({script_typeclass_path})"
                            )
                    caller.msg("\n".join(msgs))
                    if "delete" not in self.switches:
                        if script and script.pk:
                            ScriptEvMore(caller, [script], session=self.session)
                        else:
                            caller.msg("Script was deleted automatically.")
            else:
                caller.msg("No scripts found.")

    class CmdObjects(COMMAND_DEFAULT_CLASS):
        """
        statistics on objects in the database

        Usage:
          objects [<nr>]

        Gives statictics on objects in database as well as
        a list of <nr> latest objects in database. If not
        given, <nr> defaults to 10.
        """

        key = "@objects"
        locks = "cmd:perm(listobjects) or perm(Builder)"
        help_category = "System"

        def func(self):
            """Implement the command"""

            caller = self.caller
            nlim = int(self.args) if self.args and self.args.isdigit() else 10
            nobjs = ObjectDB.objects.count()
            Character = class_from_module(settings.BASE_CHARACTER_TYPECLASS)
            nchars = Character.objects.all_family().count()
            Room = class_from_module(settings.BASE_ROOM_TYPECLASS)
            nrooms = Room.objects.all_family().count()
            Exit = class_from_module(settings.BASE_EXIT_TYPECLASS)
            nexits = Exit.objects.all_family().count()
            nother = nobjs - nchars - nrooms - nexits
            nobjs = nobjs or 1  # fix zero-div error with empty database

            # total object sum table
            totaltable = self.styled_table(
                "|wtype|n", "|wcomment|n", "|wcount|n", "|w%|n", border="table", align="l"
            )
            totaltable.align = "l"
            totaltable.add_row(
                "Characters",
                "(BASE_CHARACTER_TYPECLASS + children)",
                nchars,
                "%.2f" % ((float(nchars) / nobjs) * 100),
            )
            totaltable.add_row(
                "Rooms",
                "(BASE_ROOM_TYPECLASS + children)",
                nrooms,
                "%.2f" % ((float(nrooms) / nobjs) * 100),
            )
            totaltable.add_row(
                "Exits",
                "(BASE_EXIT_TYPECLASS + children)",
                nexits,
                "%.2f" % ((float(nexits) / nobjs) * 100),
            )
            totaltable.add_row("Other", "", nother, "%.2f" % ((float(nother) / nobjs) * 100))

            # typeclass table
            typetable = self.styled_table(
                "|wtypeclass|n", "|wcount|n", "|w%|n", border="table", align="l"
            )
            typetable.align = "l"
            dbtotals = ObjectDB.objects.get_typeclass_totals()
            for stat in dbtotals:
                typetable.add_row(
                    stat.get("typeclass", "<error>"),
                    stat.get("count", -1),
                    "%.2f" % stat.get("percent", -1),
                )

            # last N table
            objs = ObjectDB.objects.all().order_by("db_date_created")[max(0, nobjs - nlim) :]
            latesttable = self.styled_table(
                "|wcreated|n", "|wdbref|n", "|wname|n", "|wtypeclass|n", align="l", border="table"
            )
            latesttable.align = "l"
            for obj in objs:
                latesttable.add_row(
                    utils.datetime_format(obj.date_created), obj.dbref, obj.key, obj.path
                )

            string = "\n|wObject subtype totals (out of %i Objects):|n\n%s" % (nobjs, totaltable)
            string += "\n|wObject typeclass distribution:|n\n%s" % typetable
            string += "\n|wLast %s Objects created:|n\n%s" % (min(nobjs, nlim), latesttable)
            caller.msg(string)

    class CmdTeleport(COMMAND_DEFAULT_CLASS):
        """
        teleport object to another location

        Usage:
          tel/switch [<object> to||=] <target location>

        Examples:
          tel Limbo
          tel/quiet box = Limbo
          tel/tonone box

        Switches:
          quiet  - don't echo leave/arrive messages to the source/target
                   locations for the move.
          intoexit - if target is an exit, teleport INTO
                     the exit object instead of to its destination
          tonone - if set, teleport the object to a None-location. If this
                   switch is set, <target location> is ignored.
                   Note that the only way to retrieve
                   an object from a None location is by direct #dbref
                   reference. A puppeted object cannot be moved to None.
          loc - teleport object to the target's location instead of its contents

        Teleports an object somewhere. If no object is given, you yourself are
        teleported to the target location.

        To lock an object from being teleported, set its `teleport` lock, it will be
        checked with the caller. To block
        a destination from being teleported to, set the destination's `teleport_here`
        lock - it will be checked with the thing being teleported. Admins and
        higher permissions can always teleport.

        """

        key = "@teleport"
        aliases = "@tel"
        switch_options = ("quiet", "intoexit", "tonone", "loc")
        rhs_split = ("=", " to ")  # Prefer = delimiter, but allow " to " usage.
        locks = "cmd:perm(teleport) or perm(Builder)"
        help_category = "Building"

        def parse(self):
            """
            Breaking out searching here to make this easier to override.

            """
            super().parse()
            self.obj_to_teleport = self.caller
            self.destination = None
            if self.rhs:
                self.obj_to_teleport = self.caller.search(self.lhs, global_search=True)
                if not self.obj_to_teleport:
                    self.caller.msg("Did not find object to teleport.")
                    raise InterruptCommand
                self.destination = self.caller.search(self.rhs, global_search=True)
            elif self.lhs:
                self.destination = self.caller.search(self.lhs, global_search=True)

        def func(self):
            """Performs the teleport"""

            caller = self.caller
            obj_to_teleport = self.obj_to_teleport
            destination = self.destination

            if "tonone" in self.switches:
                # teleporting to None

                if destination:
                    # in this case lhs is always the object to teleport
                    obj_to_teleport = destination

                if obj_to_teleport.has_account:
                    caller.msg(
                        "Cannot teleport a puppeted object "
                        "(%s, puppeted by %s) to a None-location."
                        % (obj_to_teleport.key, obj_to_teleport.account)
                    )
                    return
                caller.msg("Teleported %s -> None-location." % obj_to_teleport)
                if obj_to_teleport.location and "quiet" not in self.switches:
                    obj_to_teleport.location.msg_contents(
                        "%s teleported %s into nothingness." % (caller, obj_to_teleport), exclude=caller
                    )
                obj_to_teleport.location = None
                return

            if not self.args:
                caller.msg("Usage: teleport[/switches] [<obj> =] <target or (X,Y,Z)>||home")
                return

            if not destination:
                caller.msg("Destination not found.")
                return

            if "loc" in self.switches:
                destination = destination.location
                if not destination:
                    caller.msg("Destination has no location.")
                    return

            if obj_to_teleport == destination:
                caller.msg("You can't teleport an object inside of itself!")
                return

            if obj_to_teleport == destination.location:
                caller.msg("You can't teleport an object inside something it holds!")
                return

            if obj_to_teleport.location and obj_to_teleport.location == destination:
                caller.msg("%s is already at %s." % (obj_to_teleport, destination))
                return

            # check any locks
            if not (caller.permissions.check("Admin") or obj_to_teleport.access(caller, "teleport")):
                caller.msg(
                    f"{obj_to_teleport} 'teleport'-lock blocks you from teleporting " "it anywhere."
                )
                return

            if not (
                caller.permissions.check("Admin")
                or destination.access(obj_to_teleport, "teleport_here")
            ):
                caller.msg(
                    f"{destination} 'teleport_here'-lock blocks {obj_to_teleport} from " "moving there."
                )
                return

            # try the teleport
            if not obj_to_teleport.location:
                # teleporting from none-location
                obj_to_teleport.location = destination
                caller.msg(f"Teleported {obj_to_teleport} None -> {destination}")
            elif obj_to_teleport.move_to(
                destination,
                quiet="quiet" in self.switches,
                emit_to_obj=caller,
                use_destination="intoexit" not in self.switches,
                move_type="teleport",
            ):

                if obj_to_teleport == caller:
                    caller.msg(f"Teleported to {destination}.")
                else:
                    caller.msg(f"Teleported {obj_to_teleport} -> {destination}.")
            else:
                caller.msg("Teleportation failed.")

    class CmdTag(COMMAND_DEFAULT_CLASS):
        """
        handles the tags of an object

        Usage:
          tag[/del] <obj> [= <tag>[:<category>]]
          tag/search <tag>[:<category]

        Switches:
          search - return all objects with a given Tag
          del - remove the given tag. If no tag is specified,
                clear all tags on object.

        Manipulates and lists tags on objects. Tags allow for quick
        grouping of and searching for objects.  If only <obj> is given,
        list all tags on the object.  If /search is used, list objects
        with the given tag.
        The category can be used for grouping tags themselves, but it
        should be used with restrain - tags on their own are usually
        enough to for most grouping schemes.
        """

        key = "@tag"
        aliases = ["@tags"]
        options = ("search", "del")
        locks = "cmd:perm(tag) or perm(Builder)"
        help_category = "Building"
        arg_regex = r"(/\w+?(\s|$))|\s|$"

        def func(self):
            """Implement the tag functionality"""

            if not self.args:
                self.caller.msg("Usage: tag[/switches] <obj> [= <tag>[:<category>]]")
                return
            if "search" in self.switches:
                # search by tag
                tag = self.args
                category = None
                if ":" in tag:
                    tag, category = [part.strip() for part in tag.split(":", 1)]
                objs = search.search_tag(tag, category=category)
                nobjs = len(objs)
                if nobjs > 0:
                    catstr = (
                        " (category: '|w%s|n')" % category
                        if category
                        else ("" if nobjs == 1 else " (may have different tag categories)")
                    )
                    matchstr = ", ".join(o.get_display_name(self.caller) for o in objs)

                    string = "Found |w%i|n object%s with tag '|w%s|n'%s:\n %s" % (
                        nobjs,
                        "s" if nobjs > 1 else "",
                        tag,
                        catstr,
                        matchstr,
                    )
                else:
                    string = "No objects found with tag '%s%s'." % (
                        tag,
                        " (category: %s)" % category if category else "",
                    )
                self.caller.msg(string)
                return
            if "del" in self.switches:
                # remove one or all tags
                obj = self.caller.search(self.lhs, global_search=True)
                if not obj:
                    return
                if self.rhs:
                    # remove individual tag
                    tag = self.rhs
                    category = None
                    if ":" in tag:
                        tag, category = [part.strip() for part in tag.split(":", 1)]
                    if obj.tags.get(tag, category=category):
                        obj.tags.remove(tag, category=category)
                        string = "Removed tag '%s'%s from %s." % (
                            tag,
                            " (category: %s)" % category if category else "",
                            obj,
                        )
                    else:
                        string = "No tag '%s'%s to delete on %s." % (
                            tag,
                            " (category: %s)" % category if category else "",
                            obj,
                        )
                else:
                    # no tag specified, clear all tags
                    old_tags = [
                        "%s%s" % (tag, " (category: %s)" % category if category else "")
                        for tag, category in obj.tags.all(return_key_and_category=True)
                    ]
                    if old_tags:
                        obj.tags.clear()
                        string = "Cleared all tags from %s: %s" % (obj, ", ".join(sorted(old_tags)))
                    else:
                        string = "No Tags to clear on %s." % obj
                self.caller.msg(string)
                return
            # no search/deletion
            if self.rhs:
                # = is found; command args are of the form obj = tag
                obj = self.caller.search(self.lhs, global_search=True)
                if not obj:
                    return
                tag = self.rhs
                category = None
                if ":" in tag:
                    tag, category = [part.strip() for part in tag.split(":", 1)]
                # create the tag
                obj.tags.add(tag, category=category)
                string = "Added tag '%s'%s to %s." % (
                    tag,
                    " (category: %s)" % category if category else "",
                    obj,
                )
                self.caller.msg(string)
            else:
                # no = found - list tags on object
                obj = self.caller.search(self.args, global_search=True)
                if not obj:
                    return
                tagtuples = obj.tags.all(return_key_and_category=True)
                ntags = len(tagtuples)
                tags = [tup[0] for tup in tagtuples]
                categories = [" (category: %s)" % tup[1] if tup[1] else "" for tup in tagtuples]
                if ntags:
                    string = "Tag%s on %s: %s" % (
                        "s" if ntags > 1 else "",
                        obj,
                        ", ".join(sorted("'%s'%s" % (tags[i], categories[i]) for i in range(ntags))),
                    )
                else:
                    string = "No tags attached to %s." % obj
                self.caller.msg(string)

    # helper functions for spawn

    class CmdSpawn(COMMAND_DEFAULT_CLASS):
        """
        spawn objects from prototype

        Usage:
          spawn[/noloc] <prototype_key>
          spawn[/noloc] <prototype_dict>

          spawn/search [prototype_keykey][;tag[,tag]]
          spawn/list [tag, tag, ...]
          spawn/list modules    - list only module-based prototypes
          spawn/show [<prototype_key>]
          spawn/update <prototype_key>

          spawn/save <prototype_dict>
          spawn/edit [<prototype_key>]
          olc     - equivalent to spawn/edit

        Switches:
          noloc - allow location to be None if not specified explicitly. Otherwise,
                  location will default to caller's current location.
          search - search prototype by name or tags.
          list - list available prototypes, optionally limit by tags.
          show, examine - inspect prototype by key. If not given, acts like list.
          raw - show the raw dict of the prototype as a one-line string for manual editing.
          save - save a prototype to the database. It will be listable by /list.
          delete - remove a prototype from database, if allowed to.
          update - find existing objects with the same prototype_key and update
                   them with latest version of given prototype. If given with /save,
                   will auto-update all objects with the old version of the prototype
                   without asking first.
          edit, menu, olc - create/manipulate prototype in a menu interface.

        Example:
          spawn GOBLIN
          spawn {"key":"goblin", "typeclass":"monster.Monster", "location":"#2"}
          spawn/save {"key": "grunt", prototype: "goblin"};;mobs;edit:all()
        \f
        Dictionary keys:
          |wprototype_parent  |n - name of parent prototype to use. Required if typeclass is
                            not set. Can be a path or a list for multiple inheritance (inherits
                            left to right). If set one of the parents must have a typeclass.
          |wtypeclass  |n - string. Required if prototype_parent is not set.
          |wkey        |n - string, the main object identifier
          |wlocation   |n - this should be a valid object or #dbref
          |whome       |n - valid object or #dbref
          |wdestination|n - only valid for exits (object or dbref)
          |wpermissions|n - string or list of permission strings
          |wlocks      |n - a lock-string
          |waliases    |n - string or list of strings.
          |wndb_|n<name>  - value of a nattribute (ndb_ is stripped)

          |wprototype_key|n   - name of this prototype. Unique. Used to store/retrieve from db
                                and update existing prototyped objects if desired.
          |wprototype_desc|n  - desc of this prototype. Used in listings
          |wprototype_locks|n - locks of this prototype. Limits who may use prototype
          |wprototype_tags|n  - tags of this prototype. Used to find prototype

          any other keywords are interpreted as Attributes and their values.

        The available prototypes are defined globally in modules set in
        settings.PROTOTYPE_MODULES. If spawn is used without arguments it
        displays a list of available prototypes.

        """

        key = "@spawn"
        aliases = ["@olc"]
        switch_options = (
            "noloc",
            "search",
            "list",
            "show",
            "raw",
            "examine",
            "save",
            "delete",
            "menu",
            "olc",
            "update",
            "edit",
        )
        locks = "cmd:perm(spawn) or perm(Builder)"
        help_category = "Building"

        def _search_prototype(self, prototype_key, quiet=False):
            """
            Search for prototype and handle no/multi-match and access.

            Returns a single found prototype or None - in the
            case, the caller has already been informed of the
            search error we need not do any further action.

            """
            prototypes = protlib.search_prototype(prototype_key)
            nprots = len(prototypes)

            # handle the search result
            err = None
            if not prototypes:
                err = f"No prototype named '{prototype_key}' was found."
            elif nprots > 1:
                err = "Found {} prototypes matching '{}':\n  {}".format(
                    nprots,
                    prototype_key,
                    ", ".join(proto.get("prototype_key", "") for proto in prototypes),
                )
            else:
                # we have a single prototype, check access
                prototype = prototypes[0]
                if not self.caller.locks.check_lockstring(
                    self.caller, prototype.get("prototype_locks", ""), access_type="spawn", default=True
                ):
                    err = "You don't have access to use this prototype."

            if err:
                # return None on any error
                if not quiet:
                    self.caller.msg(err)
                return
            return prototype

        def _parse_prototype(self, inp, expect=dict):
            """
            Parse a prototype dict or key from the input and convert it safely
            into a dict if appropriate.

            Args:
                inp (str): The input from user.
                expect (type, optional):
            Returns:
                prototype (dict, str or None): The parsed prototype. If None, the error
                    was already reported.

            """
            eval_err = None
            try:
                prototype = _LITERAL_EVAL(inp)
            except (SyntaxError, ValueError) as err:
                # treat as string
                eval_err = err
                prototype = utils.to_str(inp)
            finally:
                # it's possible that the input was a prototype-key, in which case
                # it's okay for the LITERAL_EVAL to fail. Only if the result does not
                # match the expected type do we have a problem.
                if not isinstance(prototype, expect):
                    if eval_err:
                        string = (
                            f"{inp}\n{eval_err}\n|RCritical Python syntax error in argument. Only primitive "
                            "Python structures are allowed. \nMake sure to use correct "
                            "Python syntax. Remember especially to put quotes around all "
                            "strings inside lists and dicts.|n For more advanced uses, embed "
                            "funcparser callables ($funcs) in the strings."
                        )
                    else:
                        string = "Expected {}, got {}.".format(expect, type(prototype))
                    self.caller.msg(string)
                    return

            if expect == dict:
                # an actual prototype. We need to make sure it's safe,
                # so don't allow exec.
                # TODO: Exec support is deprecated. Remove completely for 1.0.
                if "exec" in prototype and not self.caller.check_permstring("Developer"):
                    self.caller.msg(
                        "Spawn aborted: You are not allowed to " "use the 'exec' prototype key."
                    )
                    return
                try:
                    # we homogenize the prototype first, to be more lenient with free-form
                    protlib.validate_prototype(protlib.homogenize_prototype(prototype))
                except RuntimeError as err:
                    self.caller.msg(str(err))
                    return
            return prototype

        def _get_prototype_detail(self, query=None, prototypes=None):
            """
            Display the detailed specs of one or more prototypes.

            Args:
                query (str, optional): If this is given and `prototypes` is not, search for
                    the prototype(s) by this query. This may be a partial query which
                    may lead to multiple matches, all being displayed.
                prototypes (list, optional): If given, ignore `query` and only show these
                    prototype-details.
            Returns:
                display (str, None): A formatted string of one or more prototype details.
                    If None, the caller was already informed of the error.

            """
            if not prototypes:
                # we need to query. Note that if query is None, all prototypes will
                # be returned.
                prototypes = protlib.search_prototype(key=query)
            if prototypes:
                return "\n".join(protlib.prototype_to_str(prot) for prot in prototypes)
            elif query:
                self.caller.msg(f"No prototype named '{query}' was found.")
            else:
                self.caller.msg("No prototypes found.")

        def _list_prototypes(self, key=None, tags=None):
            """Display prototypes as a list, optionally limited by key/tags."""
            protlib.list_prototypes(self.caller, key=key, tags=tags, session=self.session)

        @interactive
        def _update_existing_objects(self, caller, prototype_key, quiet=False):
            """
            Update existing objects (if any) with this prototype-key to the latest
            prototype version.

            Args:
                caller (Object): This is necessary for @interactive to work.
                prototype_key (str): The prototype to update.
                quiet (bool, optional): If set, don't report to user if no
                    old objects were found to update.
            Returns:
                n_updated (int): Number of updated objects.

            """
            prototype = self._search_prototype(prototype_key)
            if not prototype:
                return

            existing_objects = protlib.search_objects_with_prototype(prototype_key)
            if not existing_objects:
                if not quiet:
                    caller.msg("No existing objects found with an older version of this prototype.")
                return

            if existing_objects:
                n_existing = len(existing_objects)
                slow = " (note that this may be slow)" if n_existing > 10 else ""
                string = (
                    f"There are {n_existing} existing object(s) with an older version "
                    f"of prototype '{prototype_key}'. Should it be re-applied to them{slow}? [Y]/N"
                )
                answer = yield (string)
                if answer.lower() in ["n", "no"]:
                    caller.msg(
                        "|rNo update was done of existing objects. "
                        "Use spawn/update <key> to apply later as needed.|n"
                    )
                    return
                try:
                    n_updated = spawner.batch_update_objects_with_prototype(
                        prototype,
                        objects=existing_objects,
                        caller=caller,
                    )
                except Exception:
                    logger.log_trace()
                caller.msg(f"{n_updated} objects were updated.")
            return

        def _parse_key_desc_tags(self, argstring, desc=True):
            """
            Parse ;-separated input list.
            """
            key, desc, tags = "", "", []
            if ";" in argstring:
                parts = [part.strip().lower() for part in argstring.split(";")]
                if len(parts) > 1 and desc:
                    key = parts[0]
                    desc = parts[1]
                    tags = parts[2:]
                else:
                    key = parts[0]
                    tags = parts[1:]
            else:
                key = argstring.strip().lower()
            return key, desc, tags

        def func(self):
            """Implements the spawner"""

            caller = self.caller
            noloc = "noloc" in self.switches

            # run the menu/olc
            if (
                self.cmdstring == "olc"
                or "menu" in self.switches
                or "olc" in self.switches
                or "edit" in self.switches
            ):
                # OLC menu mode
                prototype = None
                if self.lhs:
                    prototype_key = self.lhs
                    prototype = self._search_prototype(prototype_key)
                    if not prototype:
                        return
                olc_menus.start_olc(caller, session=self.session, prototype=prototype)
                return

            if "search" in self.switches:
                # query for a key match. The arg is a search query or nothing.

                if not self.args:
                    # an empty search returns the full list
                    self._list_prototypes()
                    return

                # search for key;tag combinations
                key, _, tags = self._parse_key_desc_tags(self.args, desc=False)
                self._list_prototypes(key, tags)
                return

            if "raw" in self.switches:
                # query for key match and return the prototype as a safe one-liner string.
                if not self.args:
                    caller.msg("You need to specify a prototype-key to get the raw data for.")
                prototype = self._search_prototype(self.args)
                if not prototype:
                    return
                caller.msg(str(prototype))
                return

            if "show" in self.switches or "examine" in self.switches:
                # show a specific prot detail. The argument is a search query or empty.
                if not self.args:
                    # we don't show the list of all details, that's too spammy.
                    caller.msg("You need to specify a prototype-key to show.")
                    return

                detail_string = self._get_prototype_detail(self.args)
                if not detail_string:
                    return
                caller.msg(detail_string)
                return

            if "list" in self.switches:
                # for list, all optional arguments are tags.
                tags = self.lhslist
                err = self._list_prototypes(tags=tags)
                if err:
                    caller.msg(
                        "No prototypes found with prototype-tag(s): {}".format(
                            list_to_string(tags, "or")
                        )
                    )
                return

            if "save" in self.switches:
                # store a prototype to the database store
                if not self.args:
                    caller.msg(
                        "Usage: spawn/save [<key>[;desc[;tag,tag[,...][;lockstring]]]] = <prototype_dict>"
                    )
                    return
                if self.rhs:
                    # input on the form key = prototype
                    prototype_key, prototype_desc, prototype_tags = self._parse_key_desc_tags(self.lhs)
                    prototype_key = None if not prototype_key else prototype_key
                    prototype_desc = None if not prototype_desc else prototype_desc
                    prototype_tags = None if not prototype_tags else prototype_tags
                    prototype_input = self.rhs.strip()
                else:
                    prototype_key = prototype_desc = None
                    prototype_tags = None
                    prototype_input = self.lhs.strip()

                # handle parsing
                prototype = self._parse_prototype(prototype_input)
                if not prototype:
                    return

                prot_prototype_key = prototype.get("prototype_key")

                if not (prototype_key or prot_prototype_key):
                    caller.msg(
                        "A prototype_key must be given, either as `prototype_key = <prototype>` "
                        "or as a key 'prototype_key' inside the prototype structure."
                    )
                    return

                if prototype_key is None:
                    prototype_key = prot_prototype_key

                if prot_prototype_key != prototype_key:
                    caller.msg("(Replacing `prototype_key` in prototype with given key.)")
                    prototype["prototype_key"] = prototype_key

                if prototype_desc is not None and prot_prototype_key != prototype_desc:
                    caller.msg("(Replacing `prototype_desc` in prototype with given desc.)")
                    prototype["prototype_desc"] = prototype_desc
                if prototype_tags is not None and prototype.get("prototype_tags") != prototype_tags:
                    caller.msg("(Replacing `prototype_tags` in prototype with given tag(s))")
                    prototype["prototype_tags"] = prototype_tags

                string = ""
                # check for existing prototype (exact match)
                old_prototype = self._search_prototype(prototype_key, quiet=True)

                diff = spawner.prototype_diff(old_prototype, prototype, homogenize=True)
                diffstr = spawner.format_diff(diff)
                new_prototype_detail = self._get_prototype_detail(prototypes=[prototype])

                if old_prototype:
                    if not diffstr:
                        string = f"|yAlready existing Prototype:|n\n{new_prototype_detail}\n"
                        question = (
                            "\nThere seems to be no changes. Do you still want to (re)save? [Y]/N"
                        )
                    else:
                        string = (
                            f'|yExisting prototype "{prototype_key}" found. Change:|n\n{diffstr}\n'
                            f"|yNew changed prototype:|n\n{new_prototype_detail}"
                        )
                        question = (
                            "\n|yDo you want to apply the change to the existing prototype?|n [Y]/N"
                        )
                else:
                    string = f"|yCreating new prototype:|n\n{new_prototype_detail}"
                    question = "\nDo you want to continue saving? [Y]/N"

                answer = yield (string + question)
                if answer.lower() in ["n", "no"]:
                    caller.msg("|rSave cancelled.|n")
                    return

                # all seems ok. Try to save.
                try:
                    prot = protlib.save_prototype(prototype)
                    if not prot:
                        caller.msg("|rError saving:|R {}.|n".format(prototype_key))
                        return
                except protlib.PermissionError as err:
                    caller.msg("|rError saving:|R {}|n".format(err))
                    return
                caller.msg("|gSaved prototype:|n {}".format(prototype_key))

                # check if we want to update existing objects

                self._update_existing_objects(self.caller, prototype_key, quiet=True)
                return

            if not self.args:
                # all switches beyond this point gets a common non-arg return
                ncount = len(protlib.search_prototype())
                caller.msg(
                    "Usage: spawn <prototype-key> or {{key: value, ...}}"
                    f"\n ({ncount} existing prototypes. Use /list to inspect)"
                )
                return

            if "delete" in self.switches:
                # remove db-based prototype
                prototype_detail = self._get_prototype_detail(self.args)
                if not prototype_detail:
                    return

                string = f"|rDeleting prototype:|n\n{prototype_detail}"
                question = "\nDo you want to continue deleting? [Y]/N"
                answer = yield (string + question)
                if answer.lower() in ["n", "no"]:
                    caller.msg("|rDeletion cancelled.|n")
                    return

                try:
                    success = protlib.delete_prototype(self.args)
                except protlib.PermissionError as err:
                    retmsg = f"|rError deleting:|R {err}|n"
                else:
                    retmsg = (
                        "Deletion successful"
                        if success
                        else "Deletion failed (does the prototype exist?)"
                    )
                caller.msg(retmsg)
                return

            if "update" in self.switches:
                # update existing prototypes
                prototype_key = self.args.strip().lower()
                self._update_existing_objects(self.caller, prototype_key)
                return

            # If we get to this point, we use not switches but are trying a
            # direct creation of an object from a given prototype or -key

            prototype = self._parse_prototype(
                self.args, expect=dict if self.args.strip().startswith("{") else str
            )
            if not prototype:
                # this will only let through dicts or strings
                return

            key = "<unnamed>"
            if isinstance(prototype, str):
                # A prototype key we are looking to apply
                prototype_key = prototype
                prototype = self._search_prototype(prototype_key)

                if not prototype:
                    return

            # proceed to spawning
            try:
                for obj in spawner.spawn(prototype, caller=self.caller):
                    self.caller.msg("Spawned %s." % obj.get_display_name(self.caller))
                    if not prototype.get("location") and not noloc:
                        # we don't hardcode the location in the prototype (unless the user
                        # did so manually) - that would lead to it having to be 'removed' every
                        # time we try to update objects with this prototype in the future.
                        obj.location = caller.location
            except RuntimeError as err:
                caller.msg(err)