"""
This file was autogenerated based on code in :py:mod:`ubelt` via
dev/maintain/port_ubelt_code.py in the mkinit repo.
"""
from os.path import abspath
from os.path import exists
from os.path import expanduser
from os.path import isdir
from os.path import join
import os
from os.path import split
from os.path import dirname
from os.path import relpath
from os.path import splitext
from os.path import basename
from os.path import isfile
from os.path import realpath
import sys


IS_PY_GE_308 = ((sys.version_info[0] >= 3) and (sys.version_info[1] >= 8))


def _parse_static_node_value(node):
    """
    Extract a constant value from a node if possible
    """
    import ast
    from collections import OrderedDict
    import numbers
    if (isinstance(node, ast.Constant) and isinstance(node.value, numbers.Number) if IS_PY_GE_308 else isinstance(node, ast.Num)):
        value = node.value if IS_PY_GE_308 else node.n
    elif (isinstance(node, ast.Constant) and isinstance(node.value, str) if IS_PY_GE_308 else isinstance(node, ast.Str)):
        value = node.value if IS_PY_GE_308 else node.s
    elif isinstance(node, ast.List):
        value = list(map(_parse_static_node_value, node.elts))
    elif isinstance(node, ast.Tuple):
        value = tuple(map(_parse_static_node_value, node.elts))
    elif isinstance(node, (ast.Dict)):
        keys = map(_parse_static_node_value, node.keys)
        values = map(_parse_static_node_value, node.values)
        value = OrderedDict(zip(keys, values))
        # value = dict(zip(keys, values))
    elif isinstance(node, (ast.NameConstant)):
        value = node.value
    else:
        raise TypeError('Cannot parse a static value from non-static node '
                        'of type: {!r}'.format(type(node)))
    return value


def _extension_module_tags():
    """
    Returns valid tags an extension module might have

    Returns:
        List[str]
    """
    import sysconfig
    tags = []
    # handle PEP 3149 -- ABI version tagged .so files
    # ABI = application binary interface
    tags.append(sysconfig.get_config_var('SOABI'))
    tags.append('abi3')  # not sure why this one is valid but it is
    tags = [t for t in tags if t]
    return tags


def _static_parse(varname, fpath):
    """
    Statically parse the a constant variable from a python file

    Args:
        varname (str): variable name to extract
        fpath (str | PathLike): path to python file to parse

    Returns:
        Any: the static value

    Example:
        >>> # xdoctest: +SKIP("ubelt dependency")
        >>> dpath = ub.Path.appdir('tests/import/staticparse').ensuredir()
        >>> fpath = (dpath / 'foo.py')
        >>> fpath.write_text('a = {1: 2}')
        >>> assert _static_parse('a', fpath) == {1: 2}
        >>> fpath.write_text('a = 2')
        >>> assert _static_parse('a', fpath) == 2
        >>> fpath.write_text('a = "3"')
        >>> assert _static_parse('a', fpath) == "3"
        >>> fpath.write_text('a = ["3", 5, 6]')
        >>> assert _static_parse('a', fpath) == ["3", 5, 6]
        >>> fpath.write_text('a = ("3", 5, 6)')
        >>> assert _static_parse('a', fpath) == ("3", 5, 6)
        >>> fpath.write_text('b = 10' + chr(10) + 'a = None')
        >>> assert _static_parse('a', fpath) is None
        >>> import pytest
        >>> with pytest.raises(TypeError):
        >>>     fpath.write_text('a = list(range(10))')
        >>>     assert _static_parse('a', fpath) is None
        >>> with pytest.raises(AttributeError):
        >>>     fpath.write_text('a = list(range(10))')
        >>>     assert _static_parse('c', fpath) is None
        >>> if sys.version_info[0:2] >= (3, 6):
        >>>     # Test with type annotations
        >>>     fpath.write_text('b: int = 10')
        >>>     assert _static_parse('b', fpath) == 10
    """
    import ast

    if not exists(fpath):
        raise ValueError('fpath={!r} does not exist'.format(fpath))
    with open(fpath, 'r') as file_:
        sourcecode = file_.read()
    pt = ast.parse(sourcecode)

    class StaticVisitor(ast.NodeVisitor):
        def visit_Assign(self, node):
            for target in node.targets:
                target_id = getattr(target, 'id', None)
                if target_id == varname:
                    self.static_value = _parse_static_node_value(node.value)

        def visit_AnnAssign(self, node):
            """Handle annotated assignments like `VAR: Type = value`"""
            if getattr(node.target, 'id', None) == varname:
                if node.value is not None:
                    self.static_value = _parse_static_node_value(node.value)

    visitor = StaticVisitor()
    visitor.visit(pt)
    try:
        value = visitor.static_value
    except AttributeError:
        value = 'Unknown {}'.format(varname)
        raise AttributeError(value)
    return value


def _platform_pylib_exts():  # nocover
    """
    Returns .so, .pyd, or .dylib depending on linux, win or mac.
    On python3 return the previous with and without abi (e.g.
    .cpython-35m-x86_64-linux-gnu) flags. On python2 returns with
    and without multiarch.

    Returns:
        tuple
    """
    import sysconfig
    valid_exts = []
    # return with and without API flags
    # handle PEP 3149 -- ABI version tagged .so files
    base_ext = '.' + sysconfig.get_config_var('EXT_SUFFIX').split('.')[-1]
    for tag in _extension_module_tags():
        valid_exts.append('.' + tag + base_ext)
    valid_exts.append(base_ext)
    return tuple(valid_exts)


def _syspath_modname_to_modpath(modname, sys_path=None, exclude=None):
    """
    syspath version of modname_to_modpath

    Args:
        modname (str): name of module to find

        sys_path (None | List[str | PathLike]):
            The paths to search for the module.
            If unspecified, defaults to ``sys.path``.

        exclude (List[str | PathLike] | None):
            If specified prevents these directories from being searched.
            Defaults to None.

    Returns:
        str: path to the module.

    Note:
        This is much slower than the pkgutil mechanisms.

        There seems to be a change to the editable install mechanism:
        https://github.com/pypa/setuptools/issues/3548
        Trying to find more docs about it.

        TODO: add a test where we make an editable install, regular install,
        standalone install, and check that we always find the right path.

    Example:
        >>> print(_syspath_modname_to_modpath('xdoctest.static_analysis'))
        ...static_analysis.py
        >>> print(_syspath_modname_to_modpath('xdoctest'))
        ...xdoctest
        >>> # xdoctest: +REQUIRES(CPython)
        >>> print(_syspath_modname_to_modpath('_ctypes'))
        ..._ctypes...
        >>> assert _syspath_modname_to_modpath('xdoctest', sys_path=[]) is None
        >>> assert _syspath_modname_to_modpath('xdoctest.static_analysis', sys_path=[]) is None
        >>> assert _syspath_modname_to_modpath('_ctypes', sys_path=[]) is None
        >>> assert _syspath_modname_to_modpath('this', sys_path=[]) is None

    Example:
        >>> # test what happens when the module is not visible in the path
        >>> modname = 'xdoctest.static_analysis'
        >>> modpath = _syspath_modname_to_modpath(modname)
        >>> exclude = [split_modpath(modpath)[0]]
        >>> found = _syspath_modname_to_modpath(modname, exclude=exclude)
        >>> if found is not None:
        >>>     # Note: the basic form of this test may fail if there are
        >>>     # multiple versions of the package installed. Try and fix that.
        >>>     other = split_modpath(found)[0]
        >>>     assert other not in exclude
        >>>     exclude.append(other)
        >>>     found = _syspath_modname_to_modpath(modname, exclude=exclude)
        >>> if found is not None:
        >>>     raise AssertionError(
        >>>         'should not have found {}.'.format(found) +
        >>>         ' because we excluded: {}.'.format(exclude) +
        >>>         ' cwd={} '.format(os.getcwd()) +
        >>>         ' sys.path={} '.format(sys.path)
        >>>     )
    """
    import glob

    def _isvalid(modpath, base):
        # every directory up to the module, should have an init
        subdir = dirname(modpath)
        while subdir and subdir != base:
            if not exists(join(subdir, '__init__.py')):
                return False
            subdir = dirname(subdir)
        return True

    _fname_we = modname.replace('.', os.path.sep)
    candidate_fnames = [
        _fname_we + '.py',
        # _fname_we + '.pyc',
        # _fname_we + '.pyo',
    ]
    # Add extension library suffixes
    candidate_fnames += [_fname_we + ext for ext in _platform_pylib_exts()]

    if sys_path is None:
        sys_path = sys.path

    # the empty string in sys.path indicates cwd. Change this to a '.'
    candidate_dpaths = ['.' if p == '' else p for p in sys_path]

    if exclude:
        def normalize(p):
            if sys.platform.startswith('win32'):  # nocover
                return realpath(p).lower()
            else:
                return realpath(p)
        # Keep only the paths not in exclude
        real_exclude = {normalize(p) for p in exclude}
        candidate_dpaths = [p for p in candidate_dpaths
                            if normalize(p) not in real_exclude]

    def check_dpath(dpath):
        # Check for directory-based modules (has presidence over files)
        modpath = join(dpath, _fname_we)
        if exists(modpath):
            if isfile(join(modpath, '__init__.py')):
                if _isvalid(modpath, dpath):
                    return modpath

        # If that fails, check for file-based modules
        for fname in candidate_fnames:
            modpath = join(dpath, fname)
            if isfile(modpath):
                if _isvalid(modpath, dpath):
                    return modpath

    _pkg_name = _fname_we.split(os.path.sep)[0]
    _pkg_name_hypen = _pkg_name.replace('_', '-')

    _egglink_fname1 = _pkg_name + '.egg-link'
    _egglink_fname2 = _pkg_name_hypen + '.egg-link'
    # FIXME! suffixed modules will clobber break!
    # Currently mitigating this by looping over all possible matches,
    # but it would be nice to ensure we are not matching suffixes.
    # however, we should probably match and handle different versions.
    _editable_fname_pth_pat = '__editable__.' + _pkg_name + '-*.pth'

    # NOTE: the __editable__ finders are named after the package, but the
    # module could have a different name, so we cannot use the package name
    # (which in this case is really the module name) in the pattern, and we
    # have to check all of the finders.
    # _editable_fname_finder_py_pat = '__editable___' + _pkg_name + '_*finder.py'
    _editable_fname_finder_py_pat = '__editable___*_*finder.py'

    found_modpath = None
    for dpath in candidate_dpaths:
        modpath = check_dpath(dpath)
        if modpath:
            found_modpath = modpath
            break

        # Attempt to handle PEP660 import hooks.
        # We should look for a finder path first, because a pth might
        # not contain a real path, but code to load the finder.
        # Which one is used is defined in setuptools/editable_wheel.py
        # It will depend on an "Editable Strategy".
        # Basically a finder will be used for "complex" structures and
        # basic pth will be used for "simple" structures (which means has a
        # src/modname folder).
        new_editable_finder_paths = sorted(glob.glob(join(dpath, _editable_fname_finder_py_pat)))
        if new_editable_finder_paths:  # nocover
            # This makes some assumptions, which may not hold in general
            # We may need to fallback entirely on pkgutil, which would
            # ultimately be good. Hopefully the new standards mean it does not
            # break with pytest anymore? Nope, pytest still doesn't work right
            # with it.
            for finder_fpath in new_editable_finder_paths:
                try:
                    mapping = _static_parse('MAPPING', finder_fpath)
                except AttributeError:
                    ...
                else:
                    try:
                        target = dirname(mapping[_pkg_name])
                    except KeyError:
                        ...
                    else:
                        if not exclude or normalize(target) not in real_exclude:  # pragma: nobranch
                            modpath = check_dpath(target)
                            if modpath:  # pragma: nobranch
                                found_modpath = modpath
                                break
            if found_modpath is not None:
                break

        # If a finder does not exist, then the __editable__ pth file might hold
        # the path itself. Check for that.
        new_editable_pth_paths = sorted(glob.glob(join(dpath, _editable_fname_pth_pat)))
        if new_editable_pth_paths:  # nocover
            # Disable coverage because the test that covers this is too slow.
            # It can be made faster, re-enable when that lands.
            import pathlib
            for editable_pth in new_editable_pth_paths:
                editable_pth = pathlib.Path(editable_pth)
                target = editable_pth.read_text().strip().split('\n')[-1]
                if not exclude or normalize(target) not in real_exclude:
                    modpath = check_dpath(target)
                    if modpath:  # pragma: nobranch
                        found_modpath = modpath
                        break
            if found_modpath is not None:
                break

        # If file path checks fails, check for egg-link based modules
        # (Python usually puts egg links into sys.path, but if the user is
        #  providing the path then it is important to check them explicitly)
        linkpath1 = join(dpath, _egglink_fname1)
        linkpath2 = join(dpath, _egglink_fname2)
        linkpath = None
        if isfile(linkpath1):  # nocover
            linkpath = linkpath1
        elif isfile(linkpath2):  # nocover
            linkpath = linkpath2
        if linkpath is not None:  # nocover
            # We exclude this from coverage because its difficult to write a
            # unit test where we can enforce that there is a module installed
            # in development mode.
            # Note: the new test_editable_modules.py test can do this, but
            # this old method may no longer be supported.

            # TODO: ensure this is the correct way to parse egg-link files
            # https://setuptools.readthedocs.io/en/latest/formats.html#egg-links
            # The docs state there should only be one line, but I see two.
            with open(linkpath, 'r') as file:
                target = file.readline().strip()
            if not exclude or normalize(target) not in real_exclude:
                modpath = check_dpath(target)
                if modpath:
                    found_modpath = modpath
                    break

    return found_modpath


def modname_to_modpath(modname, hide_init=True, hide_main=False, sys_path=None):
    """
    Finds the path to a python module from its name.

    Determines the path to a python module without directly import it

    Converts the name of a module (__name__) to the path (__file__) where it is
    located without importing the module. Returns None if the module does not
    exist.

    Args:
        modname (str):
            The name of a module in ``sys_path``.

        hide_init (bool):
            if False, __init__.py will be returned for packages.
            Defaults to True.

        hide_main (bool):
            if False, and ``hide_init`` is True, __main__.py will be returned
            for packages, if it exists. Defaults to False.

        sys_path (None | List[str | PathLike]):
            The paths to search for the module.
            If unspecified, defaults to ``sys.path``.

    Returns:
        str | None:
            modpath - path to the module, or None if it doesn't exist

    Example:
        >>> modname = 'xdoctest.__main__'
        >>> modpath = modname_to_modpath(modname, hide_main=False)
        >>> assert modpath.endswith('__main__.py')
        >>> modname = 'xdoctest'
        >>> modpath = modname_to_modpath(modname, hide_init=False)
        >>> assert modpath.endswith('__init__.py')
        >>> # xdoctest: +REQUIRES(CPython)
        >>> modpath = basename(modname_to_modpath('_ctypes'))
        >>> assert 'ctypes' in modpath
    """
    if hide_main or sys_path:
        modpath = _syspath_modname_to_modpath(modname, sys_path)
    else:
        # import xdev
        # with xdev.embed_on_exception_context:
        # try:
        #     modpath = _importlib_modname_to_modpath(modname)
        # except Exception:
        #     modpath = _syspath_modname_to_modpath(modname, sys_path)
        # modpath = _pkgutil_modname_to_modpath(modname, sys_path)
        modpath = _syspath_modname_to_modpath(modname, sys_path)

    if modpath is None:
        return None

    modpath = normalize_modpath(modpath, hide_init=hide_init,
                                hide_main=hide_main)
    return modpath


def normalize_modpath(modpath, hide_init=True, hide_main=False):
    """
    Normalizes __init__ and __main__ paths.

    Args:
        modpath (str | PathLike):
            path to a module

        hide_init (bool):
            if True, always return package modules as __init__.py files
            otherwise always return the dpath. Defaults to True.

        hide_main (bool):
            if True, always strip away main files otherwise ignore __main__.py.
            Defaults to False.

    Returns:
        str | PathLike: a normalized path to the module

    Note:
        Adds __init__ if reasonable, but only removes __main__ by default

    Example:
        >>> from xdoctest import static_analysis as module
        >>> modpath = module.__file__
        >>> assert normalize_modpath(modpath) == modpath.replace('.pyc', '.py')
        >>> dpath = dirname(modpath)
        >>> res0 = normalize_modpath(dpath, hide_init=0, hide_main=0)
        >>> res1 = normalize_modpath(dpath, hide_init=0, hide_main=1)
        >>> res2 = normalize_modpath(dpath, hide_init=1, hide_main=0)
        >>> res3 = normalize_modpath(dpath, hide_init=1, hide_main=1)
        >>> assert res0.endswith('__init__.py')
        >>> assert res1.endswith('__init__.py')
        >>> assert not res2.endswith('.py')
        >>> assert not res3.endswith('.py')
    """
    if hide_init:
        if basename(modpath) == '__init__.py':
            modpath = dirname(modpath)
            hide_main = True
    else:
        # add in init, if reasonable
        modpath_with_init = join(modpath, '__init__.py')
        if exists(modpath_with_init):
            modpath = modpath_with_init
    if hide_main:
        # We can remove main, but dont add it
        if basename(modpath) == '__main__.py':
            # corner case where main might just be a module name not in a pkg
            parallel_init = join(dirname(modpath), '__init__.py')
            if exists(parallel_init):
                modpath = dirname(modpath)
    return modpath


def modpath_to_modname(modpath, hide_init=True, hide_main=False, check=True,
                       relativeto=None):
    """
    Determines importable name from file path

    Converts the path to a module (__file__) to the importable python name
    (__name__) without importing the module.

    The filename is converted to a module name, and parent directories are
    recursively included until a directory without an __init__.py file is
    encountered.

    Args:
        modpath (str):
            Module filepath

        hide_init (bool):
            Removes the __init__ suffix. Defaults to True.

        hide_main (bool):
            Removes the __main__ suffix. Defaults to False.

        check (bool):
            If False, does not raise an error if modpath is a dir and does not
            contain an __init__ file. Defaults to True.

        relativeto (str | None):
            If specified, all checks are ignored and this is considered the
            path to the root module. Defaults to None.

    TODO:
        - [ ] Does this need modification to support PEP 420?
              https://www.python.org/dev/peps/pep-0420/

    Returns:
        str: modname

    Raises:
        ValueError: if check is True and the path does not exist

    Example:
        >>> from xdoctest import static_analysis
        >>> modpath = static_analysis.__file__.replace('.pyc', '.py')
        >>> modpath = modpath.replace('.pyc', '.py')
        >>> modname = modpath_to_modname(modpath)
        >>> assert modname == 'xdoctest.static_analysis'

    Example:
        >>> import xdoctest
        >>> assert modpath_to_modname(xdoctest.__file__.replace('.pyc', '.py')) == 'xdoctest'
        >>> assert modpath_to_modname(dirname(xdoctest.__file__.replace('.pyc', '.py'))) == 'xdoctest'

    Example:
        >>> # xdoctest: +REQUIRES(CPython)
        >>> modpath = modname_to_modpath('_ctypes')
        >>> modname = modpath_to_modname(modpath)
        >>> assert modname == '_ctypes'

    Example:
        >>> modpath = '/foo/libfoobar.linux-x86_64-3.6.so'
        >>> modname = modpath_to_modname(modpath, check=False)
        >>> assert modname == 'libfoobar'
    """
    if check and relativeto is None:
        if not exists(modpath):
            raise ValueError('modpath={} does not exist'.format(modpath))
    modpath_ = abspath(expanduser(modpath))

    modpath_ = normalize_modpath(modpath_, hide_init=hide_init,
                                 hide_main=hide_main)
    if relativeto:
        dpath = dirname(abspath(expanduser(relativeto)))
        rel_modpath = relpath(modpath_, dpath)
    else:
        dpath, rel_modpath = split_modpath(modpath_, check=check)

    modname = splitext(rel_modpath)[0]
    if '.' in modname:
        modname, abi_tag = modname.split('.', 1)
    modname = modname.replace('/', '.')
    modname = modname.replace('\\', '.')
    return modname


def split_modpath(modpath, check=True):
    """
    Splits the modpath into the dir that must be in PYTHONPATH for the module
    to be imported and the modulepath relative to this directory.

    Args:
        modpath (str): module filepath
        check (bool): if False, does not raise an error if modpath is a
            directory and does not contain an ``__init__.py`` file.

    Returns:
        Tuple[str, str]: (directory, rel_modpath)

    Raises:
        ValueError: if modpath does not exist or is not a package

    Example:
        >>> from xdoctest import static_analysis
        >>> modpath = static_analysis.__file__.replace('.pyc', '.py')
        >>> modpath = abspath(modpath)
        >>> dpath, rel_modpath = split_modpath(modpath)
        >>> recon = join(dpath, rel_modpath)
        >>> assert recon == modpath
        >>> assert rel_modpath == join('xdoctest', 'static_analysis.py')
    """
    modpath_ = abspath(expanduser(modpath))
    if check:
        if not exists(modpath_):
            if not exists(modpath):
                raise ValueError('modpath={} does not exist'.format(modpath))
            raise ValueError('modpath={} is not a module'.format(modpath))
        if isdir(modpath_) and not exists(join(modpath, '__init__.py')):
            # dirs without inits are not modules
            raise ValueError('modpath={} is not a module'.format(modpath))
    full_dpath, fname_ext = split(modpath_)
    _relmod_parts = [fname_ext]
    # Recurse down directories until we are out of the package
    dpath = full_dpath
    while exists(join(dpath, '__init__.py')):
        dpath, dname = split(dpath)
        _relmod_parts.append(dname)
    relmod_parts = _relmod_parts[::-1]
    rel_modpath = os.path.sep.join(relmod_parts)
    return dpath, rel_modpath
