Straight

def straight_dbu_factory(
    kcl: KCLayout,
    additional_info: Callable[
        ...,
        dict[str, MetaData],
    ]
    | dict[str, MetaData]
    | None = None,
    output_type: type[KC] | None = None,
    port_type: str = "optical",
    **cell_kwargs: Unpack[CellKWargs],
) -> StraightFactory[KC]:
    """Returns a function generating straights [dbu length].

    The returned function is the generic interface: it accepts either a
    ``cross_section`` or the legacy ``width``/``layer``/``enclosure`` (all dbu),
    normalized into a symmetric cross section.

    Args:
        kcl: The KCLayout which will be owned
        additional_info: Add additional key/values to the
            [`KCell.info`][kfactory.settings.Info]. Can be a static dict
            mapping info name to info value. Or can a callable which takes the straight
            functions' parameters as kwargs and returns a dict with the mapping.
        cell_kwargs: Additional arguments passed as `@kcl.cell(**cell_kwargs)`.
    """
    _additional_info: dict[str, MetaData] = {}
    if _is_additional_info_func(additional_info):
        _additional_info_func: Callable[
            ...,
            dict[str, MetaData],
        ] = additional_info
    else:

        def additional_info_func(
            **kwargs: Any,
        ) -> dict[str, MetaData]:
            return {}

        _additional_info_func = additional_info_func
        _additional_info = additional_info or {}  # ty:ignore[invalid-assignment]

    ports = cell_kwargs.get("ports")
    if ports is None:
        if kcl.rename_function == rename_clockwise:
            cell_kwargs["ports"] = {"left": ["o1"], "right": ["o2"]}
        elif kcl.rename_function == rename_by_direction:
            cell_kwargs["ports"] = {"left": ["W0"], "right": ["E0"]}
    cell_kwargs.setdefault("basename", "straight")
    basename = cell_kwargs["basename"]

    if output_type is not None:
        cell = kcl.cell(output_type=output_type, **cell_kwargs)
    else:
        cell = kcl.cell(output_type=cast("type[KC]", KCell), **cell_kwargs)

    @cell
    def _straight(
        cross_section: str | AnyCrossSectionInput,
        length: dbu,
    ) -> KCell:
        """Waveguide defined by a cross section."""
        c = kcl.kcell()

        if length < 0:
            logger.critical(
                f"Negative lengths are not allowed {length} as ports"
                " will be inverted. Please use a positive number. Forcing positive"
                " lengths."
            )
            length = -length

        xs = kcl.get_base_cross_section(cross_section)

        extrude_path_cross_section(
            c, [kdb.DPoint(0.0, 0.0), kdb.DPoint(kcl.to_um(length), 0.0)], xs
        )

        c.create_port(
            name="o1",
            trans=kdb.Trans(2, False, 0, 0),
            cross_section=xs,
            port_type=port_type,
        )
        c.create_port(
            name="o2",
            trans=kdb.Trans(0, False, length, 0),
            cross_section=xs,
            port_type=port_type,
        )

        _info: dict[str, MetaData] = {
            "width_um": kcl.to_um(xs.width),
            "length_um": kcl.to_um(length),
            "width_dbu": xs.width,
            "length_dbu": length,
        }
        _info.update(_additional_info_func(cross_section=xs, length=length))
        _info.update(_additional_info)
        c.info = Info(**_info)

        c.boundary = kdb.DPolygon(c.dbbox())
        c.auto_rename_ports()
        return c

    @kcl.generic_factory(name=basename)
    def straight(
        *,
        length: dbu,
        cross_section: str
        | AnyCrossSectionInput
        | CrossSectionSpecDict
        | DCrossSectionSpecDict
        | None = None,
        width: dbu | None = None,
        layer: kdb.LayerInfo | None = None,
        enclosure: LayerEnclosure | None = None,
    ) -> KC:
        if cross_section is None:
            if width is None or layer is None:
                raise ValueError(
                    "Provide a cross_section, or width and layer (legacy call)."
                )
            xs = cross_section_from_width(kcl, width, layer, enclosure)
        else:
            xs = kcl.get_icross_section(cross_section)
        return _straight(cross_section=xs, length=length)

    return straight