#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
from __future__ import annotations

import pkgutil
from importlib import import_module
from typing import TYPE_CHECKING, Callable

if TYPE_CHECKING:
    from types import ModuleType


def import_string(dotted_path: str):
    """
    Import a dotted module path and return the attribute/class designated by the last name in the path.

    Raise ImportError if the import failed.
    """
    try:
        module_path, class_name = dotted_path.rsplit(".", 1)
    except ValueError:
        raise ImportError(f"{dotted_path} doesn't look like a module path")

    module = import_module(module_path)

    try:
        return getattr(module, class_name)
    except AttributeError:
        raise ImportError(f'Module "{module_path}" does not define a "{class_name}" attribute/class')


def qualname(o: object | Callable) -> str:
    """Convert an attribute/class/function to a string importable by ``import_string``."""
    if callable(o) and hasattr(o, "__module__") and hasattr(o, "__name__"):
        return f"{o.__module__}.{o.__name__}"

    cls = o

    if not isinstance(cls, type):  # instance or class
        cls = type(cls)

    name = cls.__qualname__
    module = cls.__module__

    if module and module != "__builtin__":
        return f"{module}.{name}"

    return name


def iter_namespace(ns: ModuleType):
    return pkgutil.iter_modules(ns.__path__, ns.__name__ + ".")