path: root/venv/lib/python3.8/site-packages/narwhals/_namespace.py

"""Narwhals-level equivalent of `CompliantNamespace`."""

from __future__ import annotations

from typing import (
    TYPE_CHECKING,
    Any,
    Callable,
    Generic,
    Literal,
    Protocol,
    TypeVar,
    overload,
)

from narwhals._compliant.typing import CompliantNamespaceAny, CompliantNamespaceT_co
from narwhals._utils import Implementation, Version
from narwhals.dependencies import (
    get_cudf,
    get_modin,
    get_pandas,
    get_polars,
    get_pyarrow,
    is_dask_dataframe,
    is_duckdb_relation,
    is_ibis_table,
    is_pyspark_connect_dataframe,
    is_pyspark_dataframe,
    is_sqlframe_dataframe,
)

if TYPE_CHECKING:
    from types import ModuleType
    from typing import ClassVar

    import duckdb
    import pandas as pd
    import polars as pl
    import pyarrow as pa
    import pyspark.sql as pyspark_sql
    from pyspark.sql.connect.dataframe import DataFrame as PySparkConnectDataFrame
    from typing_extensions import TypeAlias, TypeIs

    from narwhals._arrow.namespace import ArrowNamespace
    from narwhals._dask.namespace import DaskNamespace
    from narwhals._duckdb.namespace import DuckDBNamespace
    from narwhals._ibis.namespace import IbisNamespace
    from narwhals._pandas_like.namespace import PandasLikeNamespace
    from narwhals._polars.namespace import PolarsNamespace
    from narwhals._spark_like.dataframe import SQLFrameDataFrame
    from narwhals._spark_like.namespace import SparkLikeNamespace
    from narwhals.typing import DataFrameLike, NativeFrame, NativeLazyFrame, NativeSeries

    T = TypeVar("T")

    _Guard: TypeAlias = "Callable[[Any], TypeIs[T]]"

    _Polars: TypeAlias = Literal["polars"]
    _Arrow: TypeAlias = Literal["pyarrow"]
    _Dask: TypeAlias = Literal["dask"]
    _DuckDB: TypeAlias = Literal["duckdb"]
    _PandasLike: TypeAlias = Literal["pandas", "cudf", "modin"]
    _Ibis: TypeAlias = Literal["ibis"]
    _SparkLike: TypeAlias = Literal["pyspark", "sqlframe", "pyspark[connect]"]
    _EagerOnly: TypeAlias = "_PandasLike | _Arrow"
    _EagerAllowed: TypeAlias = "_Polars | _EagerOnly"
    _LazyOnly: TypeAlias = "_SparkLike | _Dask | _DuckDB | _Ibis"
    _LazyAllowed: TypeAlias = "_Polars | _LazyOnly"

    Polars: TypeAlias = Literal[_Polars, Implementation.POLARS]
    Arrow: TypeAlias = Literal[_Arrow, Implementation.PYARROW]
    Dask: TypeAlias = Literal[_Dask, Implementation.DASK]
    DuckDB: TypeAlias = Literal[_DuckDB, Implementation.DUCKDB]
    Ibis: TypeAlias = Literal[_Ibis, Implementation.IBIS]
    PandasLike: TypeAlias = Literal[
        _PandasLike, Implementation.PANDAS, Implementation.CUDF, Implementation.MODIN
    ]
    SparkLike: TypeAlias = Literal[
        _SparkLike,
        Implementation.PYSPARK,
        Implementation.SQLFRAME,
        Implementation.PYSPARK_CONNECT,
    ]
    EagerOnly: TypeAlias = "PandasLike | Arrow"
    EagerAllowed: TypeAlias = "EagerOnly | Polars"
    LazyOnly: TypeAlias = "SparkLike | Dask | DuckDB | Ibis"
    LazyAllowed: TypeAlias = "LazyOnly | Polars"

    BackendName: TypeAlias = "_EagerAllowed | _LazyAllowed"
    IntoBackend: TypeAlias = "BackendName | Implementation | ModuleType"

    EagerAllowedNamespace: TypeAlias = "Namespace[PandasLikeNamespace] | Namespace[ArrowNamespace] | Namespace[PolarsNamespace]"
    EagerAllowedImplementation: TypeAlias = Literal[
        Implementation.PANDAS,
        Implementation.CUDF,
        Implementation.MODIN,
        Implementation.PYARROW,
        Implementation.POLARS,
    ]

    class _NativeDask(Protocol):
        _partition_type: type[pd.DataFrame]

    class _NativeCuDF(Protocol):
        def to_pylibcudf(self, *args: Any, **kwds: Any) -> Any: ...

    class _NativeIbis(Protocol):
        def sql(self, *args: Any, **kwds: Any) -> Any: ...
        def __pyarrow_result__(self, *args: Any, **kwds: Any) -> Any: ...
        def __pandas_result__(self, *args: Any, **kwds: Any) -> Any: ...
        def __polars_result__(self, *args: Any, **kwds: Any) -> Any: ...

    class _ModinDataFrame(Protocol):
        _pandas_class: type[pd.DataFrame]

    class _ModinSeries(Protocol):
        _pandas_class: type[pd.Series[Any]]

    _NativePolars: TypeAlias = "pl.DataFrame | pl.LazyFrame | pl.Series"
    _NativeArrow: TypeAlias = "pa.Table | pa.ChunkedArray[Any]"
    _NativeDuckDB: TypeAlias = "duckdb.DuckDBPyRelation"
    _NativePandas: TypeAlias = "pd.DataFrame | pd.Series[Any]"
    _NativeModin: TypeAlias = "_ModinDataFrame | _ModinSeries"
    _NativePandasLike: TypeAlias = "_NativePandas | _NativeCuDF | _NativeModin"
    _NativeSQLFrame: TypeAlias = "SQLFrameDataFrame"
    _NativePySpark: TypeAlias = "pyspark_sql.DataFrame"
    _NativePySparkConnect: TypeAlias = "PySparkConnectDataFrame"
    _NativeSparkLike: TypeAlias = (
        "_NativeSQLFrame | _NativePySpark | _NativePySparkConnect"
    )

    NativeKnown: TypeAlias = "_NativePolars | _NativeArrow | _NativePandasLike | _NativeSparkLike | _NativeDuckDB | _NativeDask | _NativeIbis"
    NativeUnknown: TypeAlias = (
        "NativeFrame | NativeSeries | NativeLazyFrame | DataFrameLike"
    )
    NativeAny: TypeAlias = "NativeKnown | NativeUnknown"

__all__ = ["Namespace"]


class Namespace(Generic[CompliantNamespaceT_co]):
    _compliant_namespace: CompliantNamespaceT_co
    _version: ClassVar[Version] = Version.MAIN

    def __init__(self, namespace: CompliantNamespaceT_co, /) -> None:
        self._compliant_namespace = namespace

    def __init_subclass__(cls, *args: Any, version: Version, **kwds: Any) -> None:
        super().__init_subclass__(*args, **kwds)

        if isinstance(version, Version):
            cls._version = version
        else:
            msg = f"Expected {Version} but got {type(version).__name__!r}"
            raise TypeError(msg)

    def __repr__(self) -> str:
        return f"Namespace[{type(self.compliant).__name__}]"

    @property
    def compliant(self) -> CompliantNamespaceT_co:
        return self._compliant_namespace

    @property
    def implementation(self) -> Implementation:
        return self.compliant._implementation

    @property
    def version(self) -> Version:
        return self._version

    @overload
    @classmethod
    def from_backend(cls, backend: PandasLike, /) -> Namespace[PandasLikeNamespace]: ...

    @overload
    @classmethod
    def from_backend(cls, backend: Polars, /) -> Namespace[PolarsNamespace]: ...

    @overload
    @classmethod
    def from_backend(cls, backend: Arrow, /) -> Namespace[ArrowNamespace]: ...

    @overload
    @classmethod
    def from_backend(cls, backend: SparkLike, /) -> Namespace[SparkLikeNamespace]: ...

    @overload
    @classmethod
    def from_backend(cls, backend: DuckDB, /) -> Namespace[DuckDBNamespace]: ...

    @overload
    @classmethod
    def from_backend(cls, backend: Dask, /) -> Namespace[DaskNamespace]: ...

    @overload
    @classmethod
    def from_backend(cls, backend: Ibis, /) -> Namespace[IbisNamespace]: ...

    @overload
    @classmethod
    def from_backend(cls, backend: EagerAllowed, /) -> EagerAllowedNamespace: ...

    @overload
    @classmethod
    def from_backend(
        cls, backend: IntoBackend, /
    ) -> Namespace[CompliantNamespaceAny]: ...

    @classmethod
    def from_backend(
        cls: type[Namespace[Any]], backend: IntoBackend, /
    ) -> Namespace[Any]:
        """Instantiate from native namespace module, string, or Implementation.

        Arguments:
            backend: native namespace module, string, or Implementation.

        Returns:
            Namespace.

        Examples:
            >>> from narwhals._namespace import Namespace
            >>> Namespace.from_backend("polars")
            Namespace[PolarsNamespace]
        """
        impl = Implementation.from_backend(backend)
        backend_version = impl._backend_version()
        version = cls._version
        ns: CompliantNamespaceAny
        if impl.is_pandas_like():
            from narwhals._pandas_like.namespace import PandasLikeNamespace

            ns = PandasLikeNamespace(
                implementation=impl, backend_version=backend_version, version=version
            )

        elif impl.is_polars():
            from narwhals._polars.namespace import PolarsNamespace

            ns = PolarsNamespace(backend_version=backend_version, version=version)
        elif impl.is_pyarrow():
            from narwhals._arrow.namespace import ArrowNamespace

            ns = ArrowNamespace(backend_version=backend_version, version=version)
        elif impl.is_spark_like():
            from narwhals._spark_like.namespace import SparkLikeNamespace

            ns = SparkLikeNamespace(
                implementation=impl, backend_version=backend_version, version=version
            )
        elif impl.is_duckdb():
            from narwhals._duckdb.namespace import DuckDBNamespace

            ns = DuckDBNamespace(backend_version=backend_version, version=version)
        elif impl.is_dask():
            from narwhals._dask.namespace import DaskNamespace

            ns = DaskNamespace(backend_version=backend_version, version=version)
        elif impl.is_ibis():
            from narwhals._ibis.namespace import IbisNamespace

            ns = IbisNamespace(backend_version=backend_version, version=version)
        else:
            msg = "Not supported Implementation"  # pragma: no cover
            raise AssertionError(msg)
        return cls(ns)

    @overload
    @classmethod
    def from_native_object(
        cls, native: _NativePolars, /
    ) -> Namespace[PolarsNamespace]: ...

    @overload
    @classmethod
    def from_native_object(
        cls, native: _NativePandasLike, /
    ) -> Namespace[PandasLikeNamespace]: ...

    @overload
    @classmethod
    def from_native_object(cls, native: _NativeArrow, /) -> Namespace[ArrowNamespace]: ...

    @overload
    @classmethod
    def from_native_object(
        cls, native: _NativeSparkLike, /
    ) -> Namespace[SparkLikeNamespace]: ...

    @overload
    @classmethod
    def from_native_object(
        cls, native: _NativeDuckDB, /
    ) -> Namespace[DuckDBNamespace]: ...

    @overload
    @classmethod
    def from_native_object(cls, native: _NativeDask, /) -> Namespace[DaskNamespace]: ...

    @overload
    @classmethod
    def from_native_object(cls, native: _NativeIbis, /) -> Namespace[IbisNamespace]: ...

    @overload
    @classmethod
    def from_native_object(
        cls, native: NativeUnknown, /
    ) -> Namespace[CompliantNamespaceAny]: ...

    @classmethod
    def from_native_object(  # noqa: PLR0911
        cls: type[Namespace[Any]], native: NativeAny, /
    ) -> Namespace[Any]:
        if is_native_polars(native):
            return cls.from_backend(Implementation.POLARS)
        elif is_native_pandas(native):
            return cls.from_backend(Implementation.PANDAS)
        elif is_native_arrow(native):
            return cls.from_backend(Implementation.PYARROW)
        elif is_native_spark_like(native):
            return cls.from_backend(
                Implementation.SQLFRAME
                if is_native_sqlframe(native)
                else Implementation.PYSPARK_CONNECT
                if is_native_pyspark_connect(native)
                else Implementation.PYSPARK
            )
        elif is_native_dask(native):
            return cls.from_backend(Implementation.DASK)  # pragma: no cover
        elif is_native_duckdb(native):
            return cls.from_backend(Implementation.DUCKDB)
        elif is_native_cudf(native):  # pragma: no cover
            return cls.from_backend(Implementation.CUDF)
        elif is_native_modin(native):  # pragma: no cover
            return cls.from_backend(Implementation.MODIN)
        elif is_native_ibis(native):
            return cls.from_backend(Implementation.IBIS)
        else:
            msg = f"Unsupported type: {type(native).__qualname__!r}"
            raise TypeError(msg)


def is_native_polars(obj: Any) -> TypeIs[_NativePolars]:
    return (pl := get_polars()) is not None and isinstance(
        obj, (pl.DataFrame, pl.Series, pl.LazyFrame)
    )


def is_native_arrow(obj: Any) -> TypeIs[_NativeArrow]:
    return (pa := get_pyarrow()) is not None and isinstance(
        obj, (pa.Table, pa.ChunkedArray)
    )


def is_native_dask(obj: Any) -> TypeIs[_NativeDask]:
    return is_dask_dataframe(obj)


is_native_duckdb: _Guard[_NativeDuckDB] = is_duckdb_relation
is_native_sqlframe: _Guard[_NativeSQLFrame] = is_sqlframe_dataframe
is_native_pyspark: _Guard[_NativePySpark] = is_pyspark_dataframe
is_native_pyspark_connect: _Guard[_NativePySparkConnect] = is_pyspark_connect_dataframe


def is_native_pandas(obj: Any) -> TypeIs[_NativePandas]:
    return (pd := get_pandas()) is not None and isinstance(obj, (pd.DataFrame, pd.Series))


def is_native_modin(obj: Any) -> TypeIs[_NativeModin]:
    return (mpd := get_modin()) is not None and isinstance(
        obj, (mpd.DataFrame, mpd.Series)
    )  # pragma: no cover


def is_native_cudf(obj: Any) -> TypeIs[_NativeCuDF]:
    return (cudf := get_cudf()) is not None and isinstance(
        obj, (cudf.DataFrame, cudf.Series)
    )  # pragma: no cover


def is_native_pandas_like(obj: Any) -> TypeIs[_NativePandasLike]:
    return (
        is_native_pandas(obj) or is_native_cudf(obj) or is_native_modin(obj)
    )  # pragma: no cover


def is_native_spark_like(obj: Any) -> TypeIs[_NativeSparkLike]:
    return (
        is_native_sqlframe(obj)
        or is_native_pyspark(obj)
        or is_native_pyspark_connect(obj)
    )


def is_native_ibis(obj: Any) -> TypeIs[_NativeIbis]:
    return is_ibis_table(obj)