"""
    sphinx.ext.autodoc.importer
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Importer utilities for autodoc

    :copyright: Copyright 2007-2020 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

import importlib
import traceback
import warnings
from typing import Any, Callable, Dict, List, Mapping, NamedTuple, Tuple

from sphinx.util import logging
from sphinx.util.inspect import isclass, isenumclass, safe_getattr

logger = logging.getLogger(__name__)


def import_module(modname: str, warningiserror: bool = False) -> Any:
    """
    Call importlib.import_module(modname), convert exceptions to ImportError
    """
    try:
        with warnings.catch_warnings():
            warnings.filterwarnings("ignore", category=ImportWarning)
            with logging.skip_warningiserror(not warningiserror):
                return importlib.import_module(modname)
    except BaseException as exc:
        # Importing modules may cause any side effects, including
        # SystemExit, so we need to catch all errors.
        raise ImportError(exc, traceback.format_exc())


def import_object(modname: str, objpath: List[str], objtype: str = '',
                  attrgetter: Callable[[Any, str], Any] = safe_getattr,
                  warningiserror: bool = False) -> Any:
    if objpath:
        logger.debug('[autodoc] from %s import %s', modname, '.'.join(objpath))
    else:
        logger.debug('[autodoc] import %s', modname)

    try:
        module = None
        exc_on_importing = None
        objpath = list(objpath)
        while module is None:
            try:
                module = import_module(modname, warningiserror=warningiserror)
                logger.debug('[autodoc] import %s => %r', modname, module)
            except ImportError as exc:
                logger.debug('[autodoc] import %s => failed', modname)
                exc_on_importing = exc
                if '.' in modname:
                    # retry with parent module
                    modname, name = modname.rsplit('.', 1)
                    objpath.insert(0, name)
                else:
                    raise

        obj = module
        parent = None
        object_name = None
        for attrname in objpath:
            parent = obj
            logger.debug('[autodoc] getattr(_, %r)', attrname)
            obj = attrgetter(obj, attrname)
            logger.debug('[autodoc] => %r', obj)
            object_name = attrname
        return [module, parent, object_name, obj]
    except (AttributeError, ImportError) as exc:
        if isinstance(exc, AttributeError) and exc_on_importing:
            # restore ImportError
            exc = exc_on_importing

        if objpath:
            errmsg = ('autodoc: failed to import %s %r from module %r' %
                      (objtype, '.'.join(objpath), modname))
        else:
            errmsg = 'autodoc: failed to import %s %r' % (objtype, modname)

        if isinstance(exc, ImportError):
            # import_module() raises ImportError having real exception obj and
            # traceback
            real_exc, traceback_msg = exc.args
            if isinstance(real_exc, SystemExit):
                errmsg += ('; the module executes module level statement '
                           'and it might call sys.exit().')
            elif isinstance(real_exc, ImportError) and real_exc.args:
                errmsg += '; the following exception was raised:\n%s' % real_exc.args[0]
            else:
                errmsg += '; the following exception was raised:\n%s' % traceback_msg
        else:
            errmsg += '; the following exception was raised:\n%s' % traceback.format_exc()

        logger.debug(errmsg)
        raise ImportError(errmsg)


def get_module_members(module: Any) -> List[Tuple[str, Any]]:
    """Get members of target module."""
    from sphinx.ext.autodoc import INSTANCEATTR

    members = {}  # type: Dict[str, Tuple[str, Any]]
    for name in dir(module):
        try:
            value = safe_getattr(module, name, None)
            members[name] = (name, value)
        except AttributeError:
            continue

    # annotation only member (ex. attr: int)
    if hasattr(module, '__annotations__'):
        for name in module.__annotations__:
            if name not in members:
                members[name] = (name, INSTANCEATTR)

    return sorted(list(members.values()))


class Attribute(NamedTuple):
    name: str
    directly_defined: bool
    value: Any


def get_object_members(subject: Any, objpath: List[str], attrgetter: Callable,
                       analyzer: Any = None) -> Dict[str, Attribute]:
    """Get members and attributes of target object."""
    from sphinx.ext.autodoc import INSTANCEATTR

    # the members directly defined in the class
    obj_dict = attrgetter(subject, '__dict__', {})

    members = {}  # type: Dict[str, Attribute]

    # enum members
    if isenumclass(subject):
        for name, value in subject.__members__.items():
            if name not in members:
                members[name] = Attribute(name, True, value)

        superclass = subject.__mro__[1]
        for name, value in obj_dict.items():
            if name not in superclass.__dict__:
                members[name] = Attribute(name, True, value)

    # members in __slots__
    if isclass(subject) and getattr(subject, '__slots__', None) is not None:
        from sphinx.ext.autodoc import SLOTSATTR

        for name in subject.__slots__:
            members[name] = Attribute(name, True, SLOTSATTR)

    # other members
    for name in dir(subject):
        try:
            value = attrgetter(subject, name)
            directly_defined = name in obj_dict
            if name not in members:
                members[name] = Attribute(name, directly_defined, value)
        except AttributeError:
            continue

    # annotation only member (ex. attr: int)
    if hasattr(subject, '__annotations__') and isinstance(subject.__annotations__, Mapping):
        for name in subject.__annotations__:
            if name not in members:
                members[name] = Attribute(name, True, INSTANCEATTR)

    if analyzer:
        # append instance attributes (cf. self.attr1) if analyzer knows
        namespace = '.'.join(objpath)
        for (ns, name) in analyzer.find_attr_docs():
            if namespace == ns and name not in members:
                members[name] = Attribute(name, True, INSTANCEATTR)

    return members