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# Source code for betty.project

    """
    Provide the project API.

    Projects are how people use Betty. A project is a workspace, starting out with the user's configuration,
    and combining it with the resulting ancestry, allowing the user to perform tasks, such as generating a
    site from the entire project.
    """

    from __future__ import annotations

    from contextlib import suppress, asynccontextmanager
    from graphlib import TopologicalSorter, CycleError
    from pathlib import Path
    from reprlib import recursive_repr
    from typing import (
        Any,
        Generic,
        final,
        Iterable,
        Self,
        TYPE_CHECKING,
        TypeVar,
        Iterator,
        overload,
    )
    from urllib.parse import urlparse

    from aiofiles.tempfile import TemporaryDirectory
    from typing_extensions import override

    from betty import fs, event_dispatcher
    from betty import model
    from betty.assertion import (
        Assertion,
        RequiredField,
        OptionalField,
        assert_record,
        assert_setattr,
        assert_str,
        assert_bool,
        assert_dict,
        assert_locale,
        assert_int,
        assert_positive_number,
        assert_fields,
    )
    from betty.assertion.error import AssertionFailed
    from betty.assets import AssetRepository
    from betty.asyncio import wait_to_thread
    from betty.classtools import repr_instance
    from betty.config import (
        Configuration,
        Configurable,
    )
    from betty.config.collections.mapping import ConfigurationMapping
    from betty.config.collections.sequence import ConfigurationSequence
    from betty.core import CoreComponent
    from betty.event_dispatcher import EventDispatcher, EventHandlerRegistry
    from betty.hashid import hashid
    from betty.locale import DEFAULT_LOCALE
    from betty.locale.localizable import _, ShorthandStaticTranslations
    from betty.locale.localizable.config import (
        StaticTranslationsLocalizableConfigurationProperty,
    )
    from betty.locale.localizer import LocalizerRepository
    from betty.model import Entity, UserFacingEntity
    from betty.model.ancestry import Ancestry, Person, Event, Place, Source
    from betty.plugin.assertion import assert_plugin
    from betty.project import extension
    from betty.project.extension import (
        Extension,
        ConfigurableExtension,
        build_extension_type_graph,
        CyclicDependencyError,
    )
    from betty.project.factory import ProjectDependentFactory
    from betty.render import Renderer, SequentialRenderer
    from betty.serde.dump import (
        Dump,
        VoidableDump,
        void_none,
        minimize,
        VoidableDumpMapping,
    )
    from betty.serde.format import FormatRepository
    from betty.typing import Void

    if TYPE_CHECKING:
        from betty.machine_name import MachineName
        from collections.abc import AsyncIterator, Sequence
        from betty.app import App
        from betty.url import LocalizedUrlGenerator, StaticUrlGenerator
        from betty.jinja2 import Environment

    _EntityT = TypeVar("_EntityT", bound=Entity)

    #: The default age by which people are presumed dead.
    DEFAULT_LIFETIME_THRESHOLD = 125

    @final
    class EntityReference(Configuration, Generic[_EntityT]):
        """
        Configuration that references an entity from the project's ancestry.
        """

        def __init__(
            self,
            entity_type: type[_EntityT] | None = None,
            entity_id: str | None = None,
            *,
            entity_type_is_constrained: bool = False,
        ):
            super().__init__()
            self._entity_type = entity_type
            self._entity_id = entity_id
            self._entity_type_is_constrained = entity_type_is_constrained

        @property
        def entity_type(self) -> type[_EntityT] | None:
            """
            The referenced entity's type.
            """
            return self._entity_type

        @entity_type.setter
        def entity_type(self, entity_type: type[_EntityT]) -> None:
            if self._entity_type_is_constrained:
                raise AttributeError(
                    f"The entity type cannot be set, as it is already constrained to {self._entity_type}."
                )
            self._entity_type = entity_type

        @property
        def entity_id(self) -> str | None:
            """
            The referenced entity's ID.
            """
            return self._entity_id

        @entity_id.setter
        def entity_id(self, entity_id: str) -> None:
            self._entity_id = entity_id

        @entity_id.deleter
        def entity_id(self) -> None:
            self._entity_id = None

        @property
        def entity_type_is_constrained(self) -> bool:
            """
            Whether the entity type may be changed.
            """
            return self._entity_type_is_constrained

        @override
        def update(self, other: Self) -> None:
            self._entity_type = other._entity_type
            self._entity_type_is_constrained = other._entity_type_is_constrained
            self._entity_id = other._entity_id

        @override
        def load(
            self,
            dump: Dump,
        ) -> None:
            if isinstance(dump, dict) or not self.entity_type_is_constrained:
                assert_record(
                    RequiredField(
                        "entity_type",
                        assert_plugin(model.ENTITY_TYPE_REPOSITORY)
                        | assert_setattr(self, "entity_type"),
                    ),
                    OptionalField(
                        "entity_id",
                        assert_str() | assert_setattr(self, "entity_id"),
                    ),
                )(dump)
            else:
                assert_str()(dump)
                assert_setattr(self, "entity_id")(dump)

        @override
        def dump(self) -> VoidableDump:
            if self.entity_type_is_constrained:
                return void_none(self.entity_id)

            if self.entity_type is None or self.entity_id is None:
                return Void

            dump: VoidableDumpMapping[VoidableDump] = {
                "entity_type": (
                    self._entity_type.plugin_id() if self._entity_type else Void
                ),
                "entity_id": self._entity_id,
            }

            return minimize(dump)

        @override
        def __eq__(self, other: Any) -> bool:
            if not isinstance(other, EntityReference):
                return NotImplemented
            return (
                self.entity_type == other.entity_type and self.entity_id == other.entity_id
            )

    @final
    class EntityReferenceSequence(
        Generic[_EntityT], ConfigurationSequence[EntityReference[_EntityT]]
    ):
        """
        Configuration for a sequence of references to entities from the project's ancestry.
        """

        def __init__(
            self,
            entity_references: Iterable[EntityReference[_EntityT]] | None = None,
            *,
            entity_type_constraint: type[_EntityT] | None = None,
        ):
            self._entity_type_constraint = entity_type_constraint
            super().__init__(entity_references)

        @override
        def load_item(self, dump: Dump) -> EntityReference[_EntityT]:
            configuration = EntityReference[_EntityT](
                # Use a dummy entity type for now to satisfy the initializer.
                # It will be overridden when loading the dump.
                Entity  # type: ignore[arg-type]
                if self._entity_type_constraint is None
                else self._entity_type_constraint,
                entity_type_is_constrained=self._entity_type_constraint is not None,
            )
            configuration.load(dump)
            return configuration

        @override
        def _pre_add(self, configuration: EntityReference[_EntityT]) -> None:
            super()._pre_add(configuration)

            entity_type_constraint = self._entity_type_constraint
            entity_reference_entity_type = configuration._entity_type

            if entity_type_constraint is None:
                configuration._entity_type_is_constrained = False
                return

            configuration._entity_type_is_constrained = True

            if (
                entity_reference_entity_type == entity_type_constraint
                and configuration.entity_type_is_constrained
            ):
                return

            expected_entity_type_label = entity_type_constraint.plugin_label()

            if entity_reference_entity_type is None:
                raise AssertionFailed(
                    _(
                        "The entity reference must be for an entity of type {expected_entity_type_label}, but instead does not specify an entity type at all."
                    ).format(
                        expected_entity_type_label=expected_entity_type_label,
                    )
                )

            actual_entity_type_label = entity_type_constraint.plugin_label()

            raise AssertionFailed(
                _(
                    "The entity reference must be for an entity of type {expected_entity_type_label}, but instead is for an entity of type {actual_entity_type_label}."
                ).format(
                    expected_entity_type_label=expected_entity_type_label,
                    actual_entity_type_label=actual_entity_type_label,
                )
            )

    @final
    class ExtensionConfiguration(Configuration):
        """
        Configure a single extension for a project.
        """

        def __init__(
            self,
            extension_type: type[Extension],
            *,
            enabled: bool = True,
            extension_configuration: Configuration | None = None,
        ):
            super().__init__()
            self._extension_type = extension_type
            self._enabled = enabled
            if extension_configuration is None and issubclass(
                extension_type, ConfigurableExtension
            ):
                extension_configuration = extension_type.default_configuration()
            self._set_extension_configuration(extension_configuration)

        @override
        def __eq__(self, other: Any) -> bool:
            if not isinstance(other, self.__class__):
                return NotImplemented
            if self.extension_type != other.extension_type:
                return False
            if self.enabled != other.enabled:
                return False
            if self.extension_configuration != other.extension_configuration:
                return False
            return True

        @property
        def extension_type(self) -> type[Extension]:
            """
            The extension type.
            """
            return self._extension_type

        @property
        def enabled(self) -> bool:
            """
            Whether the extension is enabled.
            """
            return self._enabled

        @enabled.setter
        def enabled(self, enabled: bool) -> None:
            self._enabled = enabled

        @property
        def extension_configuration(self) -> Configuration | None:
            """
            Get the extension's own configuration.
            """
            return self._extension_configuration

        def _set_extension_configuration(
            self, extension_configuration: Configuration | None
        ) -> None:
            self._extension_configuration = extension_configuration

        @override
        def update(self, other: Self) -> None:
            self._extension_type = other._extension_type
            self._enabled = other._enabled
            self._set_extension_configuration(other._extension_configuration)

        @override
        def load(self, dump: Dump) -> None:
            assert_record(
                RequiredField(
                    "extension",
                    assert_plugin(extension.EXTENSION_REPOSITORY)
                    | assert_setattr(self, "_extension_type"),
                ),
                OptionalField("enabled", assert_bool() | assert_setattr(self, "enabled")),
                OptionalField(
                    "configuration",
                    self._assert_load_extension_configuration(self.extension_type),
                ),
            )(dump)

        def _assert_load_extension_configuration(
            self, extension_type: type[Extension]
        ) -> Assertion[Any, Configuration]:
            def _assertion(value: Any) -> Configuration:
                extension_configuration = self._extension_configuration
                if isinstance(extension_configuration, Configuration):
                    extension_configuration.load(value)
                    return extension_configuration
                raise AssertionFailed(
                    _("{extension_type} is not configurable.").format(
                        extension_type=extension_type.plugin_id()
                    )
                )

            return _assertion

        @override
        def dump(self) -> VoidableDump:
            return minimize(
                {
                    "extension": self.extension_type.plugin_id(),
                    "enabled": self.enabled,
                    "configuration": (
                        minimize(self.extension_configuration.dump())
                        if issubclass(self.extension_type, Configurable)
                        and self.extension_configuration
                        else Void
                    ),
                }
            )

    @final
    class ExtensionConfigurationMapping(
        ConfigurationMapping[type[Extension], ExtensionConfiguration]
    ):
        """
        Configure a project's extensions.
        """

        @override
        def _minimize_item_dump(self) -> bool:
            return True

        def __init__(
            self,
            configurations: Iterable[ExtensionConfiguration] | None = None,
        ):
            super().__init__(configurations)

        @override
        def load_item(self, dump: Dump) -> ExtensionConfiguration:
            dict_dump = assert_fields(
                RequiredField("extension", assert_plugin(extension.EXTENSION_REPOSITORY))
            )(dump)
            configuration = ExtensionConfiguration(dict_dump["extension"])
            configuration.load(dump)
            return configuration

        @override
        def _get_key(self, configuration: ExtensionConfiguration) -> type[Extension]:
            return configuration.extension_type

        @override
        def _load_key(
            self,
            item_dump: Dump,
            key_dump: str,
        ) -> Dump:
            dict_dump = assert_dict()(item_dump)
            dict_dump["extension"] = key_dump
            return dict_dump

        @override
        def _dump_key(self, item_dump: VoidableDump) -> tuple[VoidableDump, str]:
            dict_dump = assert_dict()(item_dump)
            return dict_dump, dict_dump.pop("extension")

        def enable(self, *extension_types: type[Extension]) -> None:
            """
            Enable the given extensions.
            """
            for extension_type in extension_types:
                try:
                    self._configurations[extension_type].enabled = True
                except KeyError:
                    self.append(ExtensionConfiguration(extension_type))

        def disable(self, *extension_types: type[Extension]) -> None:
            """
            Disable the given extensions.
            """
            for extension_type in extension_types:
                with suppress(KeyError):
                    self._configurations[extension_type].enabled = False

    @final
    class EntityTypeConfiguration(Configuration):
        """
        Configure a single entity type for a project.
        """

        def __init__(
            self,
            entity_type: type[Entity],
            *,
            generate_html_list: bool | None = None,
        ):
            super().__init__()
            self._entity_type = entity_type
            self.generate_html_list = generate_html_list  # type: ignore[assignment]

        @override
        def __eq__(self, other: Any) -> bool:
            if not isinstance(other, self.__class__):
                return NotImplemented
            if self.entity_type != other.entity_type:
                return False
            if self.generate_html_list != other.generate_html_list:
                return False
            return True

        @property
        def entity_type(self) -> type[Entity]:
            """
            The configured entity type.
            """
            return self._entity_type

        @property
        def generate_html_list(self) -> bool:
            """
            Whether to generate listing web pages for entities of this type.
            """
            return self._generate_html_list or False

        @generate_html_list.setter
        def generate_html_list(self, generate_html_list: bool | None) -> None:
            if generate_html_list and not issubclass(self._entity_type, UserFacingEntity):
                raise AssertionFailed(
                    _(
                        "Cannot generate pages for {entity_type}, because it is not a user-facing entity type."
                    ).format(entity_type=self._entity_type.plugin_label())
                )
            self._generate_html_list = generate_html_list

        @override
        def update(self, other: Self) -> None:
            self._entity_type = other._entity_type
            self._generate_html_list = other._generate_html_list

        @override
        def load(self, dump: Dump) -> None:
            assert_record(
                RequiredField[Any, type[Entity]](
                    "entity_type",
                    assert_str()
                    | assert_plugin(model.ENTITY_TYPE_REPOSITORY)
                    | assert_setattr(self, "_entity_type"),
                ),
                OptionalField(
                    "generate_html_list",
                    assert_bool() | assert_setattr(self, "generate_html_list"),
                ),
            )(dump)

        @override
        def dump(self) -> VoidableDump:
            dump: VoidableDumpMapping[VoidableDump] = {
                "entity_type": self._entity_type.plugin_id(),
                "generate_html_list": (
                    Void if self._generate_html_list is None else self._generate_html_list
                ),
            }

            return minimize(dump)

    @final
    class EntityTypeConfigurationMapping(
        ConfigurationMapping[type[Entity], EntityTypeConfiguration]
    ):
        """
        Configure the entity types for a project.
        """

        @override
        def _minimize_item_dump(self) -> bool:
            return True

        @override
        def _get_key(self, configuration: EntityTypeConfiguration) -> type[Entity]:
            return configuration.entity_type

        @override
        def _load_key(
            self,
            item_dump: Dump,
            key_dump: str,
        ) -> Dump:
            dict_dump = assert_dict()(item_dump)
            assert_plugin(model.ENTITY_TYPE_REPOSITORY)(key_dump)
            dict_dump["entity_type"] = key_dump
            return dict_dump

        @override
        def _dump_key(self, item_dump: VoidableDump) -> tuple[VoidableDump, str]:
            dict_dump = assert_dict()(item_dump)
            return dict_dump, dict_dump.pop("entity_type")

        @override
        def load_item(self, dump: Dump) -> EntityTypeConfiguration:
            # Use a dummy entity type for now to satisfy the initializer.
            # It will be overridden when loading the dump.
            configuration = EntityTypeConfiguration(
                Entity  # type: ignore[type-abstract]
            )
            configuration.load(dump)
            return configuration

    @final
    class LocaleConfiguration(Configuration):
        """
        Configure a single project locale.
        """

        def __init__(
            self,
            locale: str,
            *,
            alias: str | None = None,
        ):
            super().__init__()
            self._locale = locale
            if alias is not None and "/" in alias:
                raise AssertionFailed(_("Locale aliases must not contain slashes."))
            self._alias = alias

        @override  # type: ignore[callable-functiontype]
        @recursive_repr()
        def __repr__(self) -> str:
            return repr_instance(self, locale=self.locale, alias=self.alias)

        @override
        def __eq__(self, other: Any) -> bool:
            if not isinstance(other, self.__class__):
                return NotImplemented
            if self.locale != other.locale:
                return False
            if self.alias != other.alias:
                return False
            return True

        @override
        def __hash__(self) -> int:
            return hash((self._locale, self._alias))

        @property
        def locale(self) -> str:
            """
            An `IETF BCP 47 <https://tools.ietf.org/html/bcp47>`_ language tag.
            """
            return self._locale

        @property
        def alias(self) -> str:
            """
            A shorthand alias to use instead of the full language tag, such as when rendering URLs.
            """
            if self._alias is None:
                return self.locale
            return self._alias

        @alias.setter
        def alias(self, alias: str | None) -> None:
            self._alias = alias

        @override
        def update(self, other: Self) -> None:
            self._locale = other._locale
            self._alias = other._alias

        @override
        def load(self, dump: Dump) -> None:
            assert_record(
                RequiredField("locale", assert_locale() | assert_setattr(self, "_locale")),
                OptionalField("alias", assert_str() | assert_setattr(self, "alias")),
            )(dump)

        @override
        def dump(self) -> VoidableDump:
            return minimize({"locale": self.locale, "alias": void_none(self._alias)})

    @final
    class LocaleConfigurationSequence(ConfigurationSequence[LocaleConfiguration]):
        """
        Configure a project's locales.
        """

        def __init__(
            self,
            configurations: Iterable[LocaleConfiguration] | None = None,
        ):
            super().__init__(configurations)
            self._ensure_locale()

        @override
        @overload
        def __getitem__(self, configuration_key: int | str) -> LocaleConfiguration:
            pass  # pragma: no cover

        @override
        @overload
        def __getitem__(self, configuration_key: slice) -> Sequence[LocaleConfiguration]:
            pass  # pragma: no cover

        @override
        def __getitem__(
            self, configuration_key: int | slice | str
        ) -> LocaleConfiguration | Sequence[LocaleConfiguration]:
            if isinstance(configuration_key, str):
                for configuration in self:
                    if configuration.locale == configuration_key:
                        return configuration
                raise KeyError
            return self._configurations[configuration_key]

        def __delitem__(self, configuration_key: int | str) -> None:
            if isinstance(configuration_key, str):
                for index, configuration in enumerate(self):
                    if configuration.locale == configuration_key:
                        self.remove(index)
                        return
                raise KeyError
            self.remove(configuration_key)

        @override
        def _pre_add(self, configuration: LocaleConfiguration) -> None:
            try:
                self[configuration.locale]
            except KeyError:
                pass
            else:
                raise ValueError(f'Cannot add locale "{configuration.locale}" twice.')

        @override
        def _post_remove(self, configuration: LocaleConfiguration) -> None:
            super()._post_remove(configuration)
            self._ensure_locale()

        def _ensure_locale(self) -> None:
            if len(self) == 0:
                self.append(LocaleConfiguration(DEFAULT_LOCALE))

        @override
        def update(self, other: Self) -> None:
            # Prevent the events from being dispatched.
            self._configurations.clear()
            self.append(*other)

        @override
        def replace(self, *configurations: LocaleConfiguration) -> None:
            # Prevent the events from being dispatched.
            self._configurations.clear()
            self.append(*configurations)
            self._ensure_locale()

        @override
        def load_item(self, dump: Dump) -> LocaleConfiguration:
            item = LocaleConfiguration("und")
            item.load(dump)
            return item

        @property
        def default(self) -> LocaleConfiguration:
            """
            The default language.
            """
            return self._configurations[0]

        @property
        def multilingual(self) -> bool:
            """
            Whether the configuration is multilingual.
            """
            return len(self) > 1

    @final
    class ProjectConfiguration(Configuration):
        """
        Provide the configuration for a :py:class:`betty.project.Project`.
        """

        title = StaticTranslationsLocalizableConfigurationProperty("title")
        author = StaticTranslationsLocalizableConfigurationProperty("author", minimum=0)

        def __init__(
            self,
            configuration_file_path: Path,
            *,
            url: str = "https://example.com",
            clean_urls: bool = False,
            title: ShorthandStaticTranslations = "Betty",
            author: ShorthandStaticTranslations | None = None,
            entity_types: Iterable[EntityTypeConfiguration] | None = None,
            extensions: Iterable[ExtensionConfiguration] | None = None,
            debug: bool = False,
            locales: Iterable[LocaleConfiguration] | None = None,
            lifetime_threshold: int = DEFAULT_LIFETIME_THRESHOLD,
            name: str | None = None,
        ):
            super().__init__()
            self._configuration_file_path = configuration_file_path
            self._name = name
            self._computed_name: str | None = None
            self._url = url
            self._clean_urls = clean_urls
            self.title = title
            if author:
                self.author = author
            self._entity_types = EntityTypeConfigurationMapping(
                entity_types
                or [
                    EntityTypeConfiguration(
                        entity_type=Person,
                        generate_html_list=True,
                    ),
                    EntityTypeConfiguration(
                        entity_type=Event,
                        generate_html_list=True,
                    ),
                    EntityTypeConfiguration(
                        entity_type=Place,
                        generate_html_list=True,
                    ),
                    EntityTypeConfiguration(
                        entity_type=Source,
                        generate_html_list=True,
                    ),
                ]
            )
            self._extensions = ExtensionConfigurationMapping(extensions or ())
            self._debug = debug
            self._locales = LocaleConfigurationSequence(locales or ())
            self._lifetime_threshold = lifetime_threshold

        @property
        def configuration_file_path(self) -> Path:
            """
            The path to the configuration's file.
            """
            return self._configuration_file_path

        @configuration_file_path.setter
        def configuration_file_path(self, configuration_file_path: Path) -> None:
            if configuration_file_path == self._configuration_file_path:
                return
            formats = FormatRepository()
            formats.format_for(configuration_file_path.suffix[1:])
            self._configuration_file_path = configuration_file_path

        @property
        def name(self) -> str | None:
            """
            The project's machine name.
            """
            return self._name

        @name.setter
        def name(self, name: str) -> None:
            self._name = name

        @property
        def project_directory_path(self) -> Path:
            """
            The project directory path.

            Betty will look for resources in this directory, and place generated artifacts there. It is expected
            that no other applications or projects share this same directory.
            """
            return self.configuration_file_path.parent

        @property
        def output_directory_path(self) -> Path:
            """
            The output directory path.
            """
            return self.project_directory_path / "output"

        @property
        def assets_directory_path(self) -> Path:
            """
            The :doc:`assets directory path </usage/assets>`.
            """
            return self.project_directory_path / "assets"

        @property
        def www_directory_path(self) -> Path:
            """
            The WWW directory path.
            """
            return self.output_directory_path / "www"

        def localize_www_directory_path(self, locale: str) -> Path:
            """
            Get the WWW directory path for a locale.
            """
            if self.locales.multilingual:
                return self.www_directory_path / self.locales[locale].alias
            return self.www_directory_path

        @property
        def url(self) -> str:
            """
            The project's public URL.
            """
            return self._url

        @url.setter
        def url(self, url: str) -> None:
            url_parts = urlparse(url)
            if not url_parts.scheme:
                raise AssertionFailed(
                    _("The URL must start with a scheme such as https:// or http://.")
                )
            if not url_parts.netloc:
                raise AssertionFailed(_("The URL must include a host."))
            self._url = f"{url_parts.scheme}://{url_parts.netloc}{url_parts.path}"

        @property
        def base_url(self) -> str:
            """
            The project's public URL's base URL.

            If the public URL is ``https://example.com``, the base URL is ``https://example.com``.
            If the public URL is ``https://example.com/my-ancestry-site``, the base URL is ``https://example.com``.
            If the public URL is ``https://my-ancestry-site.example.com``, the base URL is ``https://my-ancestry-site.example.com``.
            """
            url_parts = urlparse(self.url)
            return f"{url_parts.scheme}://{url_parts.netloc}"

        @property
        def root_path(self) -> str:
            """
            The project's public URL's root path.

            If the public URL is ``https://example.com``, the root path is an empty string.
            If the public URL is ``https://example.com/my-ancestry-site``, the root path is ``/my-ancestry-site``.
            """
            return urlparse(self.url).path

        @property
        def clean_urls(self) -> bool:
            """
            Whether to generate clean URLs such as ``/person/first-person`` instead of ``/person/first-person/index.html``.

            Generated artifacts will require web server that supports this.
            """
            return self._clean_urls

        @clean_urls.setter
        def clean_urls(self, clean_urls: bool) -> None:
            self._clean_urls = clean_urls

        @property
        def locales(self) -> LocaleConfigurationSequence:
            """
            The available locales.
            """
            return self._locales

        @property
        def entity_types(self) -> EntityTypeConfigurationMapping:
            """
            The available entity types.
            """
            return self._entity_types

        @property
        def extensions(self) -> ExtensionConfigurationMapping:
            """
            Then extensions running within this application.
            """
            return self._extensions

        @property
        def debug(self) -> bool:
            """
            Whether to enable debugging for project jobs.

            This setting is disabled by default.

            Enabling this generally results in:

            - More verbose logging output
            - job artifacts (e.g. generated sites)
            """
            return self._debug

        @debug.setter
        def debug(self, debug: bool) -> None:
            self._debug = debug

        @property
        def lifetime_threshold(self) -> int:
            """
            The lifetime threshold indicates when people are considered dead.

            This setting defaults to :py:const:`betty.project.DEFAULT_LIFETIME_THRESHOLD`.

            The value is an integer expressing the age in years over which people are
            presumed to have died.
            """
            return self._lifetime_threshold

        @lifetime_threshold.setter
        def lifetime_threshold(self, lifetime_threshold: int) -> None:
            assert_positive_number()(lifetime_threshold)
            self._lifetime_threshold = lifetime_threshold

        @override
        def update(self, other: Self) -> None:
            self._url = other._url
            self.title.update(other.author)
            self.author.update(other.author)
            self._clean_urls = other._clean_urls
            self._debug = other._debug
            self._lifetime_threshold = other._lifetime_threshold
            self._locales.update(other._locales)
            self._extensions.update(other._extensions)
            self._entity_types.update(other._entity_types)

        @override
        def load(self, dump: Dump) -> None:
            assert_record(
                OptionalField("name", assert_str() | assert_setattr(self, "name")),
                RequiredField("url", assert_str() | assert_setattr(self, "url")),
                OptionalField("title", self.title.load),
                OptionalField("author", self.author.load),
                OptionalField(
                    "clean_urls",
                    assert_bool() | assert_setattr(self, "clean_urls"),
                ),
                OptionalField("debug", assert_bool() | assert_setattr(self, "debug")),
                OptionalField(
                    "lifetime_threshold",
                    assert_int() | assert_setattr(self, "lifetime_threshold"),
                ),
                OptionalField("locales", self.locales.load),
                OptionalField("extensions", self.extensions.load),
                OptionalField("entity_types", self.entity_types.load),
            )(dump)

        @override
        def dump(self) -> VoidableDumpMapping[Dump]:
            return minimize(
                {  # type: ignore[return-value]
                    "name": void_none(self.name),
                    "url": self.url,
                    "title": self.title.dump(),
                    "clean_urls": void_none(self.clean_urls),
                    "author": self.author.dump(),
                    "debug": void_none(self.debug),
                    "lifetime_threshold": void_none(self.lifetime_threshold),
                    "locales": self.locales.dump(),
                    "extensions": self.extensions.dump(),
                    "entity_types": self.entity_types.dump(),
                },
                True,
            )

    @final
    class Project(Configurable[ProjectConfiguration], CoreComponent):
        """
        Define a Betty project.

        A project combines project configuration and the resulting ancestry.
        """

        def __init__(
            self,
            app: App,
            configuration: ProjectConfiguration,
            *,
            ancestry: Ancestry | None = None,
        ):
            super().__init__()
            self._app = app
            self._configuration = configuration
            self._ancestry = Ancestry() if ancestry is None else ancestry

            self._assets: AssetRepository | None = None
            self._localizers: LocalizerRepository | None = None
            self._url_generator: LocalizedUrlGenerator | None = None
            self._static_url_generator: StaticUrlGenerator | None = None
            self._jinja2_environment: Environment | None = None
            self._renderer: Renderer | None = None
            self._extensions: _ProjectExtensions | None = None
            self._event_dispatcher: EventDispatcher | None = None
            self._entity_types: set[type[Entity]] | None = None

        @classmethod
        @asynccontextmanager
        async def new_temporary(
            cls, app: App, *, ancestry: Ancestry | None = None
        ) -> AsyncIterator[Self]:
            """
            Creat a new, temporary, isolated project.

            The project will not leave any traces on the system, except when it uses
            global Betty functionality such as caches.
            """
            async with (
                TemporaryDirectory() as project_directory_path_str,
            ):
                yield cls(
                    app,
                    ProjectConfiguration(Path(project_directory_path_str) / "betty.json"),
                    ancestry=ancestry,
                )

        @override
        async def bootstrap(self) -> None:
            await super().bootstrap()
            for project_extension_batch in self.extensions:
                batch_event_handlers = EventHandlerRegistry()
                for project_extension in project_extension_batch:
                    await self._async_exit_stack.enter_async_context(project_extension)
                    project_extension.register_event_handlers(batch_event_handlers)
                self.event_dispatcher.add_registry(batch_event_handlers)

        @property
        def app(self) -> App:
            """
            The application this project is run within.
            """
            return self._app

        @property
        def name(self) -> str:
            """
            The project name.

            If no project name was configured, this defaults to the hash of the configuration file path.
            """
            if self._configuration.name is None:
                return hashid(str(self._configuration.configuration_file_path))
            return self._configuration.name

        @property
        def ancestry(self) -> Ancestry:
            """
            The project's ancestry.
            """
            return self._ancestry

        @property
        def assets(self) -> AssetRepository:
            """
            The assets file system.
            """
            if self._assets is None:
                self._assert_bootstrapped()
                asset_paths = [self.configuration.assets_directory_path]
                for extension in self.extensions.flatten():
                    extension_assets_directory_path = extension.assets_directory_path()
                    if extension_assets_directory_path is not None:
                        asset_paths.append(extension_assets_directory_path)
                # Mimic :py:attr:`betty.app.App.assets`.
                asset_paths.append(fs.ASSETS_DIRECTORY_PATH)
                self._assets = AssetRepository(*asset_paths)
            return self._assets

        @property
        def localizers(self) -> LocalizerRepository:
            """
            The available localizers.
            """
            if self._localizers is None:
                self._assert_bootstrapped()
                self._localizers = LocalizerRepository(self.assets)
            return self._localizers

        @property
        def url_generator(self) -> LocalizedUrlGenerator:
            """
            The (localized) URL generator.
            """
            if self._url_generator is None:
                from betty.url import ProjectUrlGenerator

                self._assert_bootstrapped()
                self._url_generator = ProjectUrlGenerator(self)
            return self._url_generator

        @property
        def static_url_generator(self) -> StaticUrlGenerator:
            """
            The static URL generator.
            """
            if self._static_url_generator is None:
                from betty.url import StaticPathUrlGenerator

                self._assert_bootstrapped()
                self._static_url_generator = StaticPathUrlGenerator(self.configuration)
            return self._static_url_generator

        @property
        def jinja2_environment(self) -> Environment:
            """
            The Jinja2 environment.
            """
            if not self._jinja2_environment:
                from betty.jinja2 import Environment

                self._assert_bootstrapped()
                self._jinja2_environment = Environment(self)

            return self._jinja2_environment

        @property
        def renderer(self) -> Renderer:
            """
            The (file) content renderer.
            """
            if not self._renderer:
                from betty.jinja2 import Jinja2Renderer

                self._renderer = SequentialRenderer(
                    [
                        Jinja2Renderer(self.jinja2_environment, self.configuration),
                    ]
                )

            return self._renderer

        @property
        def extensions(self) -> _ProjectExtensions:
            """
            The enabled extensions.
            """
            if self._extensions is None:
                self._assert_bootstrapped()
                extension_types_enabled_in_configuration = set()
                for (
                    project_extension_configuration
                ) in self.configuration.extensions.values():
                    if project_extension_configuration.enabled:
                        wait_to_thread(
                            project_extension_configuration.extension_type.enable_requirement().assert_met()
                        )
                        extension_types_enabled_in_configuration.add(
                            project_extension_configuration.extension_type
                        )

                extension_types_sorter = TopologicalSorter(
                    wait_to_thread(
                        build_extension_type_graph(extension_types_enabled_in_configuration)
                    )
                )
                try:
                    extension_types_sorter.prepare()
                except CycleError:
                    raise CyclicDependencyError(
                        [
                            app_extension_configuration.extension_type
                            for app_extension_configuration in self.configuration.extensions.values()
                        ]
                    ) from None

                extensions = []
                while extension_types_sorter.is_active():
                    extension_types_batch = extension_types_sorter.get_ready()
                    extensions_batch = []
                    for extension_type in extension_types_batch:
                        extension = self.new_dependent(extension_type)
                        if (
                            isinstance(extension, ConfigurableExtension)
                            and extension_type in self.configuration.extensions
                        ):
                            extension.configuration.update(
                                self.configuration.extensions[
                                    extension_type
                                ].extension_configuration
                            )
                        extensions_batch.append(extension)
                        extension_types_sorter.done(extension_type)
                    extensions.append(
                        sorted(
                            extensions_batch, key=lambda extension: extension.plugin_id()
                        )
                    )
                self._extensions = _ProjectExtensions(extensions)

            return self._extensions

        @property
        def event_dispatcher(self) -> EventDispatcher:
            """
            The event dispatcher.
            """
            if self._event_dispatcher is None:
                self._assert_bootstrapped()
                self._event_dispatcher = EventDispatcher()

            return self._event_dispatcher

        def new_dependent(
            self, dependent: type[_ProjectDependentFactoryT]
        ) -> _ProjectDependentFactoryT:
            """
            Create a new instance of a type that depends on a ``self``.
            """
            return dependent.new_for_project(self)

    _ProjectDependentFactoryT = TypeVar(
        "_ProjectDependentFactoryT", bound=ProjectDependentFactory
    )

    @final
    class _ProjectExtensions:
        """
        Manage the extensions running within the :py:class:`betty.project.Project`.
        """

        def __init__(self, project_extensions: Sequence[Sequence[Extension]]):
            super().__init__()
            self._project_extensions = project_extensions

        def __getitem__(self, extension_id: MachineName) -> Extension:
            extension_type = wait_to_thread(
                extension.EXTENSION_REPOSITORY.get(extension_id)
            )
            for project_extension in self.flatten():
                if type(project_extension) is extension_type:
                    return project_extension
            raise KeyError(f'Unknown extension of type "{extension_type}"')

        def __iter__(self) -> Iterator[Iterator[Extension]]:
            """
            Iterate over all extensions, in topologically sorted batches.

            Each item is a batch of extensions. Items are ordered because later items depend
            on earlier items. The extensions in each item do not depend on each other and their
            order has no meaning. However, implementations SHOULD sort the extensions in each
            item in a stable fashion for reproducability.
            """
            # Use a generator so we discourage calling code from storing the result.
            for batch in self._project_extensions:
                yield (project_extension for project_extension in batch)

        def flatten(self) -> Iterator[Extension]:
            """
            Get a sequence of topologically sorted extensions.
            """
            for batch in self:
                yield from batch

        def __contains__(self, extension_id: MachineName) -> bool:
            try:
                self[extension_id]
            except KeyError:
                return False
            else:
                return True

    class ProjectEvent(event_dispatcher.Event):
        """
        An event that is dispatched within the context of a :py:class:`betty.project.Project`.
        """

        def __init__(self, project: Project):
            self._project = project

        @property
        def project(self) -> Project:
            """
            The :py:class:`betty.project.Project` this event is dispatched within.
            """
            return self._project