digitalfabrik/integreat-cms

View on GitHub
integreat_cms/cms/models/regions/region.py

Summary

Maintainability
A
0 mins
Test Coverage
A
93%
from __future__ import annotations

import logging
from datetime import datetime
from html import escape
from typing import TYPE_CHECKING

from dateutil.relativedelta import relativedelta
from django.apps import apps
from django.conf import settings
from django.contrib.auth import get_user_model
from django.core.validators import MaxValueValidator, MinValueValidator
from django.db import models
from django.db.models import Q, Subquery
from django.http import Http404
from django.template.defaultfilters import floatformat
from django.urls import reverse
from django.utils import timezone as django_timezone
from django.utils.functional import cached_property, keep_lazy_text
from django.utils.translation import gettext, override
from django.utils.translation import gettext_lazy as _

if TYPE_CHECKING:
    from django.db.models.query import QuerySet
    from django.utils.functional import Promise
    from django.utils.safestring import SafeString

    from ..languages.language import Language
    from ..languages.language_tree_node import LanguageTreeNode
    from ..pages.imprint_page import ImprintPage
    from ..pages.page import PageQuerySet

from django.utils.safestring import mark_safe

from ....matomo_api.matomo_api_client import MatomoApiClient
from ....nominatim_api.utils import BoundingBox
from ...constants import (
    administrative_division,
    machine_translation_permissions,
    months,
    region_status,
    status,
)
from ...utils.translation_utils import gettext_many_lazy as __
from ..abstract_base_model import AbstractBaseModel
from ..offers.offer_template import OfferTemplate

logger = logging.getLogger(__name__)


@keep_lazy_text
def format_mt_help_text(help_text: Promise) -> str:
    """
    Helper function to lazily format help text with number separators

    :param help_text: MT field help text to format
    :return: formatted help text
    """
    return help_text.format(
        floatformat(settings.MT_CREDITS_ADDON, "g"),
        floatformat(settings.MT_CREDITS_FREE, "g"),
    )


# pylint: disable=too-few-public-methods
class RegionManager(models.Manager):
    """
    This manager annotates each region object with its language tree root node.
    This is done because it is required to calculate the region's
    :attr:`~integreat_cms.cms.models.regions.region.Region.default_language` which is called in
    :attr:`~integreat_cms.cms.models.regions.region.Region.full_name`.
    """

    def get_queryset(self) -> QuerySet:
        """
        Get the queryset of regions including the custom attribute ``language_tree_root`` which contains the root node
        of the region's language tree.

        :return: The queryset of regions
        """
        # Get model instead of importing it to avoid circular imports
        LanguageTreeNode = apps.get_model(
            app_label="cms", model_name="LanguageTreeNode"
        )
        return (
            super()
            .get_queryset()
            .prefetch_related(
                models.Prefetch(
                    "language_tree_nodes",
                    queryset=LanguageTreeNode.objects.all().select_related("language"),
                    to_attr="prefetched_language_tree_nodes",
                )
            )
        )


# pylint: disable=too-many-public-methods
class Region(AbstractBaseModel):
    """
    Data model representing region.
    """

    name = models.CharField(max_length=200, verbose_name=_("name"))
    #: See `community identification number <https://en.wikipedia.org/wiki/Community_Identification_Number>`__
    #: and `Gemeindeschlüssel (German) <https://de.wikipedia.org/wiki/Amtlicher_Gemeindeschl%C3%BCssel>`__
    common_id = models.CharField(
        max_length=48,
        blank=True,
        verbose_name=_("community identification number"),
        help_text=_(
            "Number sequence for identifying politically independent administrative units"
        ),
    )
    slug = models.SlugField(
        max_length=200,
        unique=True,
        allow_unicode=True,
        verbose_name=_("URL parameter"),
        help_text=__(
            _("Unique string identifier without spaces and special characters."),
            _("Leave blank to generate unique parameter from name"),
        ),
    )
    #: Manage choices in :mod:`~integreat_cms.cms.constants.region_status`
    status = models.CharField(
        max_length=8,
        choices=region_status.CHOICES,
        default=region_status.HIDDEN,
        verbose_name=_("status"),
    )

    #: Manage choices in :mod:`~integreat_cms.cms.constants.administrative_division`.
    #: Also see `administrative division <https://en.wikipedia.org/wiki/Administrative_division>`__.
    administrative_division = models.CharField(
        max_length=24,
        choices=administrative_division.CHOICES,
        default=administrative_division.RURAL_DISTRICT,
        verbose_name=_("administrative division"),
    )
    aliases = models.JSONField(
        default=dict,
        blank=True,
        verbose_name=_("aliases"),
        help_text=__(
            _("E.g. smaller municipalities in that area."),
            _("If empty, the CMS will try to fill this automatically."),
            _("Specify as JSON."),
        ),
    )
    custom_prefix = models.CharField(
        max_length=48,
        blank=True,
        verbose_name=_("custom prefix"),
        help_text=__(
            _("Enter parts of the name that should not affect sorting."),
            _(
                "Use this field only if the prefix is not an available choice in the list of administrative divisions above."
            ),
        ),
    )
    events_enabled = models.BooleanField(
        default=True,
        verbose_name=_("activate events"),
        help_text=_("Whether or not events are enabled in the region"),
    )
    locations_enabled = models.BooleanField(
        default=False,
        verbose_name=_("activate locations"),
        help_text=_("Whether or not locations are enabled in the region"),
    )
    push_notifications_enabled = models.BooleanField(
        default=True,
        verbose_name=_("activate push notifications"),
        help_text=_("Whether or not push notifications are enabled in the region"),
    )
    latitude = models.FloatField(
        null=True,
        verbose_name=_("latitude"),
        help_text=_("The latitude coordinate of an approximate center of the region"),
    )
    longitude = models.FloatField(
        null=True,
        verbose_name=_("longitude"),
        help_text=_("The longitude coordinate of an approximate center of the region"),
    )
    longitude_min = models.FloatField(
        null=True,
        blank=True,
        verbose_name=_("minimum longitude"),
        help_text=_("The left boundary of the region"),
        validators=[MinValueValidator(-180.0), MaxValueValidator(180.0)],
    )
    latitude_min = models.FloatField(
        null=True,
        blank=True,
        verbose_name=_("minimum latitude"),
        help_text=_("The bottom boundary of the region"),
        validators=[MinValueValidator(-90.0), MaxValueValidator(90.0)],
    )
    longitude_max = models.FloatField(
        null=True,
        blank=True,
        verbose_name=_("maximum longitude"),
        help_text=_("The right boundary of the region"),
        validators=[MinValueValidator(-180.0), MaxValueValidator(180.0)],
    )
    latitude_max = models.FloatField(
        null=True,
        blank=True,
        verbose_name=_("maximum latitude"),
        help_text=_("The top boundary of the region"),
        validators=[MinValueValidator(-90.0), MaxValueValidator(90.0)],
    )
    postal_code = models.CharField(
        max_length=10,
        verbose_name=_("postal code"),
        help_text=_(
            "For districts, enter the postcode of the administrative headquarters."
        ),
    )

    admin_mail = models.EmailField(
        verbose_name=_("email address of the administrator"),
    )

    timezone = models.CharField(
        max_length=150,
        default=settings.CURRENT_TIME_ZONE,
        verbose_name=_("timezone"),
    )
    created_date = models.DateTimeField(
        default=django_timezone.now,
        verbose_name=_("creation date"),
    )
    last_updated = models.DateTimeField(
        auto_now=True,
        verbose_name=_("modification date"),
    )

    statistics_enabled = models.BooleanField(
        default=False,
        verbose_name=_("activate statistics"),
        help_text=_("Whether or not statistics are enabled for the region"),
    )
    seo_enabled = models.BooleanField(
        default=False,
        verbose_name=_("activate SEO section"),
        help_text=_(
            "Enable possibility to fill meta description for pages, events and locations"
        ),
    )
    matomo_id = models.PositiveSmallIntegerField(
        null=True,
        blank=True,
        verbose_name=_("Matomo ID"),
        help_text=__(
            _("The Matomo ID of this region."),
            _("Will be automatically derived from the Matomo access token."),
        ),
    )
    matomo_token = models.CharField(
        max_length=150,
        blank=True,
        default="",
        verbose_name=_("Matomo authentication token"),
        help_text=_(
            "The secret Matomo access token of the region is used to authenticate in API requests"
        ),
    )

    page_permissions_enabled = models.BooleanField(
        default=False,
        verbose_name=_("activate page-specific permissions"),
        help_text=_(
            "This allows individual users to be granted the right to edit or publish a specific page."
        ),
    )

    icon = models.ForeignKey(
        "cms.MediaFile",
        verbose_name=_("logo"),
        on_delete=models.SET_NULL,
        related_name="icon_regions",
        blank=True,
        null=True,
    )

    chat_enabled = models.BooleanField(
        default=True,
        verbose_name=_("activate author chat"),
        help_text=_(
            "This gives all users of this region access to the cross-regional author chat."
        ),
    )

    administrative_division_included = models.BooleanField(
        default=False,
        verbose_name=_("include administrative division into name"),
        help_text=__(
            _(
                "Determines whether the administrative division is displayed next to the region name."
            ),
            _(
                "Sorting is always based on the name, independently from the administrative division."
            ),
        ),
    )

    offers = models.ManyToManyField(
        OfferTemplate,
        related_name="regions",
        blank=True,
        verbose_name=_("offers"),
        help_text=__(
            _(
                "Integreat offers are extended features apart from pages and events and are usually offered by a third party."
            ),
            _(
                "In most cases, the url is an external API endpoint which the frontend apps can query and render the results inside the Integreat app."
            ),
        ),
    )

    short_urls_enabled = models.BooleanField(
        default=False,
        verbose_name=_("Activate short urls"),
        help_text=_("Please check the box if you want to use short urls."),
    )

    external_news_enabled = models.BooleanField(
        default=False,
        verbose_name=_("Enable external news"),
        help_text=_(
            "Enable to display external articles in addition to local news managed by the CMS"
        ),
    )

    fallback_translations_enabled = models.BooleanField(
        default=True,
        verbose_name=_("Show content in default language as fallback"),
        help_text=_(
            "Whether or not events and locations are shown in default language as fallback"
        ),
    )

    hix_enabled = models.BooleanField(
        default=False,
        verbose_name=_("Activate HIX analysis"),
        help_text=_(
            "Allow users of this region to analyze understandability of text content via TextLab API."
        ),
    )

    summ_ai_enabled = models.BooleanField(
        default=False,
        verbose_name=_("activate automatic translations via SUMM.AI"),
        help_text=_(
            "Whether automatic translations into Easy German with SUMM.AI are enabled"
        ),
    )

    mt_renewal_month = models.PositiveIntegerField(
        choices=months.CHOICES,
        default=months.JANUARY,
        verbose_name=_("Credits renewal date for foreign language translation"),
        help_text=_("Budget usage will be reset on the 1st of the month"),
    )

    mt_addon_booked = models.BooleanField(
        default=False,
        verbose_name=_("Add-on package for foreign languages booked"),
        help_text=format_mt_help_text(
            _(
                "This makes {} translation credits available to the region in addition to the {} free ones."
            )
        ),
    )

    mt_midyear_start_month = models.PositiveIntegerField(
        default=None,
        blank=True,
        null=True,
        choices=months.CHOICES,
        verbose_name=_("Budget year start date for foreign language translation"),
        help_text=_("Month from which the add-on package was booked"),
    )

    mt_budget_used = models.PositiveIntegerField(
        default=0,
        verbose_name=_("used budget"),
    )

    machine_translate_pages = models.PositiveIntegerField(
        choices=machine_translation_permissions.CHOICES,
        default=machine_translation_permissions.EVERYONE,
        verbose_name=_("Pages"),
    )

    machine_translate_events = models.PositiveIntegerField(
        choices=machine_translation_permissions.CHOICES,
        default=machine_translation_permissions.EVERYONE,
        verbose_name=_("Events"),
    )

    machine_translate_pois = models.PositiveIntegerField(
        choices=machine_translation_permissions.CHOICES,
        default=machine_translation_permissions.EVERYONE,
        verbose_name=_("Locations"),
    )

    integreat_chat_enabled = models.BooleanField(
        default=False,
        verbose_name=_("Enable Integreat Chat"),
        help_text=_("Toggle the Integreat Chat on/off."),
    )

    zammad_url = models.URLField(
        max_length=256,
        blank=True,
        null=True,
        default=None,
        unique=True,
        verbose_name=_("Zammad-URL"),
        help_text=_(
            "URL pointing to this region's Zammad instance. Setting this enables Zammad form offers."
        ),
    )
    zammad_access_token = models.CharField(
        max_length=64,
        blank=True,
        default="",
        verbose_name=_("Zammad access token"),
        help_text=_(
            'Access token for a Zammad user account. In Zammad, the account must be part of the "Agent" role and have full group permissions for the group:'
        ),
    )
    zammad_chat_handlers = models.CharField(
        max_length=1024,
        blank=True,
        default="",
        verbose_name=_("Zammad chat handlers"),
        help_text=_(
            "Comma-separated email addresses of the accounts which should automatically be subscribed to new chat tickets. Note that these users must have full group permissions for the group:"
        ),
    )

    chat_beta_tester_percentage = models.IntegerField(
        default=0,
        blank=True,
        validators=[MinValueValidator(0), MaxValueValidator(100)],
        verbose_name=_("Chat beta tester percentage"),
        help_text=_(
            "Percentage of users selected as beta testers for the Integreat Chat feature"
        ),
    )

    #: Custom model manager :class:`~integreat_cms.cms.models.regions.region.RegionManager` for region objects
    objects = RegionManager()

    @cached_property
    def has_bounding_box(self) -> bool:
        """
        Whether the region has an individual bounding box

        :return: Whether all required coordinates for the bounding box are set
        """
        return all(
            [
                self.longitude_min,
                self.latitude_min,
                self.longitude_max,
                self.latitude_max,
            ]
        )

    @cached_property
    def bounding_box(self) -> BoundingBox:
        """
        The bounding box of the region

        :return: A bounding box object
        """
        if self.has_bounding_box:
            return BoundingBox(
                self.latitude_min,
                self.latitude_max,
                self.longitude_min,
                self.longitude_max,
            )
        return settings.DEFAULT_BOUNDING_BOX

    @cached_property
    def language_tree(self) -> list[LanguageTreeNode]:
        """
        This property returns a list of all
        :class:`~integreat_cms.cms.models.languages.language_tree_node.LanguageTreeNode` objects of this region.

        :return: A list of all language tree nodes of this region
        """
        # Prevent ValueError for unsaved regions
        if not self.pk:
            return []
        try:
            # Try to get the prefetched language tree
            return self.prefetched_language_tree_nodes
        except AttributeError:
            # If the tree was not prefetched, query it from the database
            # (this should only happen in rare edge cases)
            return list(self.language_tree_nodes.all().select_related("language"))

    @cached_property
    def language_node_by_id(self) -> dict[int, LanguageTreeNode]:
        """
        This property returns this region's language tree nodes indexed by ids

        :return: A mapping from language tree node ids to their language tree nodes in this region
        """
        return {node.id: node for node in self.language_tree}

    @cached_property
    def language_node_by_slug(self) -> dict[str, LanguageTreeNode]:
        """
        This property returns this region's language tree nodes indexed by slugs

        :return: A mapping from language slugs to their language tree nodes in this region
        """
        return {node.slug: node for node in self.language_tree}

    @cached_property
    def languages(self) -> list[Language]:
        """
        This property returns a list of all :class:`~integreat_cms.cms.models.languages.language.Language` objects
        which have a :class:`~integreat_cms.cms.models.languages.language_tree_node.LanguageTreeNode` which belongs to
        this region.

        :return: A list of all :class:`~integreat_cms.cms.models.languages.language.Language` instances of this region
        """
        return [node.language for node in self.language_tree]

    def get_source_language(self, language_slug: str) -> Language | None:
        """
        This property returns this region's source language of a given language object

        :param language_slug: The slug of the requested language
        :return: The source language of the given language in this region
        """
        try:
            parent_id = self.language_node_by_slug.get(language_slug).parent_id
            return self.language_node_by_id.get(parent_id).language
        except AttributeError:
            return None

    @cached_property
    def active_languages(self) -> list[Language]:
        """
        This property returns a list of all :class:`~integreat_cms.cms.models.languages.language.Language` objects
        which have  an active :class:`~integreat_cms.cms.models.languages.language_tree_node.LanguageTreeNode` which
        belongs to this region.

        :return: A list of all active :class:`~integreat_cms.cms.models.languages.language.Language` instances of this region
        """
        return [node.language for node in self.language_tree if node.active]

    @cached_property
    def visible_languages(self) -> list[Language]:
        """
        This property returns a list of all :class:`~integreat_cms.cms.models.languages.language.Language` objects
        which have an active & visible :class:`~integreat_cms.cms.models.languages.language_tree_node.LanguageTreeNode`
        which belongs to this region.

        :return: A list of all active & visible :class:`~integreat_cms.cms.models.languages.language.Language` instances of this region
        """
        return [
            node.language for node in self.language_tree if node.active and node.visible
        ]

    @cached_property
    def language_tree_root(self) -> LanguageTreeNode | None:
        """
        This property returns the root node of the region's language tree

        :return: The region's language root node
        """
        return next(iter(self.language_tree), None)

    @cached_property
    def default_language(self) -> Language | None:
        """
        This property returns the language :class:`~integreat_cms.cms.models.languages.language.Language` which
        corresponds to the root :class:`~integreat_cms.cms.models.languages.language_tree_node.LanguageTreeNode` of this
        region.

        :return: The root :class:`~integreat_cms.cms.models.languages.language.Language` of a region
        """
        return self.language_tree_root.language if self.language_tree_root else None

    @cached_property
    def prefix(self) -> str:
        """
        This property returns the administrative division of a region if it's included in the name.
        If this region has no default language, this property returns an empty string

        :return: The prefix of the region
        """
        if self.custom_prefix:
            return self.custom_prefix
        if self.administrative_division_included and self.default_language:
            # Get administrative division in region's default language
            with override(self.default_language.slug):
                return str(self.get_administrative_division_display())
        return ""

    @cached_property
    def full_name(self) -> str:
        """
        This property returns the full name of a region including its administrative division

        :return: The full name of the region
        """
        return f"{self.prefix} {self.name}".strip()

    @cached_property
    def region_users(self) -> QuerySet:
        """
        This property returns a QuerySet of all :class:`~django.contrib.auth.models.User` objects which belong to this
        region and are neither superusers nor staff.

        :return: A QuerySet of all :class:`~django.contrib.auth.models.User` object instances of a region
        """
        return get_user_model().objects.filter(
            regions=self,
            is_superuser=False,
            is_staff=False,
        )

    @cached_property
    def statistics(self) -> MatomoApiClient:
        """
        This property returns the MatomoApiClient of the current region.

        :return: The statistics manager
        """
        return MatomoApiClient(self)

    def get_language_or_404(
        self, language_slug: str, only_active: bool = False, only_visible: bool = False
    ) -> Language:
        """
        This class method returns the requested language of this region with optional filters ``active`` and ``visible``

        :param language_slug: The slug of the requested language
        :param only_active: Whether to return only active languages
        :param only_visible: Whether to return only visible languages
        :raises ~django.http.Http404: When no language with the given slug exists for this region and this filters

        :return: The requested :class:`~integreat_cms.cms.models.languages.language.Language` of this region
        """
        try:
            node = self.language_node_by_slug[language_slug]
            if only_active and not node.active:
                raise KeyError(
                    f"Language {node.language} is not active in region {self}"
                )
            if only_visible and not node.visible:
                raise KeyError(
                    f"Language {node.language} is not visible in region {self}"
                )
            return node.language
        except KeyError as e:
            raise Http404("No language matches the given query.") from e

    @property
    def explicitly_archived_ancestors_subquery(self) -> PageQuerySet:
        """
        This property returns a subquery for all explicitly archived ancestors of a given page.
        Needs to be used as part of another query because in order to resolve :class:`~django.db.models.OuterRef`,
        e.g. in a :class:`~django.db.models.Subquery` or in :class:`~django.db.models.Exists`.

        :return: A queryset of the explicitly archived ancestors.
        """

        return self.pages.filter(
            tree_id=models.OuterRef("tree_id"),
            lft__lt=models.OuterRef("lft"),
            rgt__gt=models.OuterRef("rgt"),
            explicitly_archived=True,
        )

    @cached_property
    def archived_pages(self) -> PageQuerySet:
        """
        This property returns a QuerySet of all archived pages and their descendants of this region.

        :return: A QuerySet of all archived pages of this region
        """

        return self.pages.filter(
            id=models.Case(
                models.When(
                    models.Exists(
                        self.explicitly_archived_ancestors_subquery.values("pk")
                    ),
                    then=models.F("pk"),
                ),
                models.When(
                    explicitly_archived=True,
                    then=models.F("pk"),
                ),
                default=None,
            )
        )

    @cached_property
    def non_archived_pages(self) -> PageQuerySet:
        """
        This property returns a QuerySet of all non-archived pages of this region.
        A page is considered as "non-archived" if its ``explicitly_archived`` property is ``False`` and all the
        page's ancestors are not archived as well.

        :return: A QuerySet of all non-archived pages of this region
        """

        return self.pages.filter(
            id=models.Case(
                models.When(
                    models.Exists(
                        self.explicitly_archived_ancestors_subquery.values("pk")
                    ),
                    then=None,
                ),
                default=models.F("pk"),
            ),
            explicitly_archived=False,
        )

    @cached_property
    def latest_page_translations(self) -> QuerySet:
        """
        :return: A QuerySet of all PageTranslations of this region that are non-archived and the latest version.
        """
        # Get model instead of importing it to avoid circular imports
        PageTranslation = apps.get_model(app_label="cms", model_name="PageTranslation")
        return PageTranslation.objects.filter(
            page__id__in=Subquery(self.non_archived_pages.values("pk")),
        ).distinct("page__id", "language__id")

    def get_pages(
        self,
        archived: bool = False,
        prefetch_translations: bool = False,
        prefetch_major_translations: bool = False,
        prefetch_public_translations: bool = False,
        annotate_language_tree: bool = False,
    ) -> PageQuerySet:
        """
        This method returns either all archived or all non-archived pages of this region.
        To retrieve all pages independently of their archived-state, use the reverse foreign key
        :attr:`~integreat_cms.cms.models.regions.region.Region.pages`.

        :param archived: Whether only archived pages should be returned (default: ``False``)
        :param prefetch_translations: Whether the latest translations for each language should be prefetched (default: ``False``)
        :param prefetch_major_translations: Whether the latest major translations for each language should be prefetched (default: ``False``)
        :param prefetch_public_translations: Whether the latest public translations for each language should be prefetched (default: ``False``)
        :param annotate_language_tree: Whether the pages should be annotated with the region's language tree (default: ``False``)
        :return: Either the archived or the non-archived pages of this region
        """
        pages = self.archived_pages if archived else self.non_archived_pages
        if prefetch_translations:
            pages = pages.prefetch_translations()
        if prefetch_major_translations:
            pages = pages.prefetch_major_translations()
        if prefetch_public_translations:
            pages = pages.prefetch_public_translations()
        if annotate_language_tree:
            pages = pages.annotate(language_tree=models.Subquery(self.language_tree))
        return pages

    def get_root_pages(self) -> PageQuerySet:
        """
        This method returns all root pages of this region.

        :return: This region's root pages
        """
        # Get model instead of importing it to avoid circular imports
        Page = apps.get_model(app_label="cms", model_name="Page")
        return Page.get_root_pages(region_slug=self.slug)

    def outdated_pages(
        self, translation_ids: QuerySet | list | None = None
    ) -> QuerySet:
        """
        Returns the outdated pages of this region. A page is outdated if it has not been updated in a configurable amount of time.

        :param translation_ids: Limit to the result to these ids. If None is passed, all latest page translations will be used.
        :return: The number of outdated pages of this region.
        """
        # Get model instead of importing it to avoid circular imports
        PageTranslation = apps.get_model(app_label="cms", model_name="PageTranslation")

        if not self.default_language:
            return PageTranslation.objects.none()

        if translation_ids is None:
            translation_ids = self.latest_page_translations.values_list("id", flat=True)

        outdated_threshold_date = datetime.now() - relativedelta(
            days=settings.OUTDATED_THRESHOLD_DAYS
        )

        outdated_pages = (
            PageTranslation.objects.filter(
                language__slug=self.default_language.slug,
                id__in=translation_ids,
                last_updated__lte=outdated_threshold_date.date(),
                status=status.PUBLIC,
            )
            .order_by("last_updated")
            .exclude(Q(content="") & Q(page__mirrored_page=None))
        )

        return outdated_pages

    @classmethod
    def search(cls, query: str) -> QuerySet[Region]:
        """
        Searches for all regions which match the given `query` in their name.
        :param query: The query string used for filtering the regions
        :return: A query for all matching objects
        """
        return cls.objects.filter(name__icontains=query)

    @cached_property
    def imprint(self) -> ImprintPage | None:
        """
        This property returns this region's imprint

        :return: The imprint of this region
        """
        return self.imprints.first()

    @property
    def mt_budget(self) -> int:
        """
        Calculate the maximum translation credit budget (number of words)

        :return: The region's total MT budget
        """
        # All regions which did not book the add-on get the free credits
        if not self.mt_addon_booked:
            return settings.MT_CREDITS_FREE
        # All regions which did book the add-on, but not mid-year, get the add-on credits
        if not self.mt_midyear_start_month:
            return settings.MT_CREDITS_ADDON + settings.MT_CREDITS_FREE
        # All regions which booked the add-on in mid-year get a fraction of the add-on credits
        # Calculate how many months lie between the renewal month and the start month of the add-on
        months_difference = self.mt_renewal_month - self.mt_midyear_start_month
        # Calculate the available fraction of the add-on
        multiplier = (months_difference % 12) / 12
        return int(multiplier * settings.MT_CREDITS_ADDON + settings.MT_CREDITS_FREE)

    @property
    def mt_budget_remaining(self) -> int:
        """
        Calculate the remaining translation credit budget (number of words)

        :return: The region's remaining MT budget
        """
        return max(0, self.mt_budget - self.mt_budget_used)

    @cached_property
    def backend_edit_link(self) -> str:
        """
        This function returns the absolute url to the edit form of this region

        :return: The url
        """
        return reverse(
            "edit_region",
            kwargs={
                "slug": self.slug,
            },
        )

    @cached_property
    def last_content_update(self) -> datetime:
        """
        Find the latest date at which any content of the
        region has been modified.

        :return: the last content update date
        """
        min_date = django_timezone.make_aware(
            django_timezone.datetime.min, django_timezone.get_default_timezone()
        )

        latest_page_update = (
            self.pages.aggregate(
                latest_update=models.Max("translations__last_updated")
            )["latest_update"]
            or min_date
        )
        latest_poi_update = (
            self.pois.aggregate(latest_update=models.Max("translations__last_updated"))[
                "latest_update"
            ]
            or min_date
        )
        latest_event_update = (
            self.events.aggregate(
                latest_update=models.Max("translations__last_updated")
            )["latest_update"]
            or min_date
        )
        latest_imprint_update = (
            self.imprint.translations.aggregate(
                latest_update=models.Max("last_updated")
            )["latest_update"]
            if self.imprint
            else None
        ) or min_date

        return max(
            latest_page_update,
            latest_poi_update,
            latest_event_update,
            latest_imprint_update,
            self.last_updated,
        )

    def __str__(self) -> SafeString:
        """
        This overwrites the default Django :meth:`~django.db.models.Model.__str__` method which would return ``Region object (id)``.
        It is used in the Django admin backend and as label for ModelChoiceFields.

        :return: A readable string representation of the region
        """
        label = escape(self.full_name)
        if self.status == region_status.HIDDEN:
            # Add warning if region is hidden
            label += " (⚠ " + gettext("Hidden") + ")"
        elif self.status == region_status.ARCHIVED:
            # Add warning if region is archived
            label += " (⚠ " + gettext("Archived") + ")"
        # mark as safe so that the warning triangle is not escaped
        return mark_safe(label)

    def get_repr(self) -> str:
        """
        This overwrites the default Django ``__repr__()`` method which would return ``<Region: Region object (id)>``.
        It is used for logging.

        :return: The canonical string representation of the region
        """
        return f"<Region (id: {self.id}, slug: {self.slug})>"

    class Meta:
        #: The verbose name of the model
        verbose_name = _("region")
        #: The plural verbose name of the model
        verbose_name_plural = _("regions")
        #: The default permissions for this model
        default_permissions = ("change", "delete", "view")
        #: The default sorting for this model
        ordering = ["name"]