"""
Improved support for Microsoft Visual C++ compilers.

Known supported compilers:
--------------------------
Microsoft Visual C++ 9.0:
    Microsoft Visual C++ Compiler for Python 2.7 (x86, amd64)
    Microsoft Windows SDK 6.1 (x86, x64, ia64)
    Microsoft Windows SDK 7.0 (x86, x64, ia64)

Microsoft Visual C++ 10.0:
    Microsoft Windows SDK 7.1 (x86, x64, ia64)

Microsoft Visual C++ 14.X:
    Microsoft Visual C++ Build Tools 2015 (x86, x64, arm)
    Microsoft Visual Studio Build Tools 2017 (x86, x64, arm, arm64)
    Microsoft Visual Studio Build Tools 2019 (x86, x64, arm, arm64)

This may also support compilers shipped with compatible Visual Studio versions.
"""

import json
from io import open
from os import listdir, pathsep
from os.path import join, isfile, isdir, dirname
import sys
import platform
import itertools
import subprocess
import distutils.errors
from setuptools.extern.packaging.version import LegacyVersion

from .monkey import get_unpatched

if platform.system() == 'Windows':
    import winreg
    from os import environ
else:
    # Mock winreg and environ so the module can be imported on this platform.

    class winreg:
        HKEY_USERS = None
        HKEY_CURRENT_USER = None
        HKEY_LOCAL_MACHINE = None
        HKEY_CLASSES_ROOT = None

    environ = dict()

_msvc9_suppress_errors = (
    # msvc9compiler isn't available on some platforms
    ImportError,

    # msvc9compiler raises DistutilsPlatformError in some
    # environments. See #1118.
    distutils.errors.DistutilsPlatformError,
)

try:
    from distutils.msvc9compiler import Reg
except _msvc9_suppress_errors:
    pass


def msvc9_find_vcvarsall(version):
    """
    Patched "distutils.msvc9compiler.find_vcvarsall" to use the standalone
    compiler build for Python
    (VCForPython / Microsoft Visual C++ Compiler for Python 2.7).

    Fall back to original behavior when the standalone compiler is not
    available.

    Redirect the path of "vcvarsall.bat".

    Parameters
    ----------
    version: float
        Required Microsoft Visual C++ version.

    Return
    ------
    str
        vcvarsall.bat path
    """
    vc_base = r'Software\%sMicrosoft\DevDiv\VCForPython\%0.1f'
    key = vc_base % ('', version)
    try:
        # Per-user installs register the compiler path here
        productdir = Reg.get_value(key, "installdir")
    except KeyError:
        try:
            # All-user installs on a 64-bit system register here
            key = vc_base % ('Wow6432Node\\', version)
            productdir = Reg.get_value(key, "installdir")
        except KeyError:
            productdir = None

    if productdir:
        vcvarsall = join(productdir, "vcvarsall.bat")
        if isfile(vcvarsall):
            return vcvarsall

    return get_unpatched(msvc9_find_vcvarsall)(version)


def msvc9_query_vcvarsall(ver, arch='x86', *args, **kwargs):
    """
    Patched "distutils.msvc9compiler.query_vcvarsall" for support extra
    Microsoft Visual C++ 9.0 and 10.0 compilers.

    Set environment without use of "vcvarsall.bat".

    Parameters
    ----------
    ver: float
        Required Microsoft Visual C++ version.
    arch: str
        Target architecture.

    Return
    ------
    dict
        environment
    """
    # Try to get environment from vcvarsall.bat (Classical way)
    try:
        orig = get_unpatched(msvc9_query_vcvarsall)
        return orig(ver, arch, *args, **kwargs)
    except distutils.errors.DistutilsPlatformError:
        # Pass error if Vcvarsall.bat is missing
        pass
    except ValueError:
        # Pass error if environment not set after executing vcvarsall.bat
        pass

    # If error, try to set environment directly
    try:
        return EnvironmentInfo(arch, ver).return_env()
    except distutils.errors.DistutilsPlatformError as exc:
        _augment_exception(exc, ver, arch)
        raise


def _msvc14_find_vc2015():
    """Python 3.8 "distutils/_msvccompiler.py" backport"""
    try:
        key = winreg.OpenKey(
            winreg.HKEY_LOCAL_MACHINE,
            r"Software\Microsoft\VisualStudio\SxS\VC7",
            0,
            winreg.KEY_READ | winreg.KEY_WOW64_32KEY
        )
    except OSError:
        return None, None

    best_version = 0
    best_dir = None
    with key:
        for i in itertools.count():
            try:
                v, vc_dir, vt = winreg.EnumValue(key, i)
            except OSError:
                break
            if v and vt == winreg.REG_SZ and isdir(vc_dir):
                try:
                    version = int(float(v))
                except (ValueError, TypeError):
                    continue
                if version >= 14 and version > best_version:
                    best_version, best_dir = version, vc_dir
    return best_version, best_dir


def _msvc14_find_vc2017():
    """Python 3.8 "distutils/_msvccompiler.py" backport

    Returns "15, path" based on the result of invoking vswhere.exe
    If no install is found, returns "None, None"

    The version is returned to avoid unnecessarily changing the function
    result. It may be ignored when the path is not None.

    If vswhere.exe is not available, by definition, VS 2017 is not
    installed.
    """
    root = environ.get("ProgramFiles(x86)") or environ.get("ProgramFiles")
    if not root:
        return None, None

    try:
        path = subprocess.check_output([
            join(root, "Microsoft Visual Studio", "Installer", "vswhere.exe"),
            "-latest",
            "-prerelease",
            "-requires", "Microsoft.VisualStudio.Component.VC.Tools.x86.x64",
            "-property", "installationPath",
            "-products", "*",
        ]).decode(encoding="mbcs", errors="strict").strip()
    except (subprocess.CalledProcessError, OSError, UnicodeDecodeError):
        return None, None

    path = join(path, "VC", "Auxiliary", "Build")
    if isdir(path):
        return 15, path

    return None, None


PLAT_SPEC_TO_RUNTIME = {
    'x86': 'x86',
    'x86_amd64': 'x64',
    'x86_arm': 'arm',
    'x86_arm64': 'arm64'
}


def _msvc14_find_vcvarsall(plat_spec):
    """Python 3.8 "distutils/_msvccompiler.py" backport"""
    _, best_dir = _msvc14_find_vc2017()
    vcruntime = None

    if plat_spec in PLAT_SPEC_TO_RUNTIME:
        vcruntime_plat = PLAT_SPEC_TO_RUNTIME[plat_spec]
    else:
        vcruntime_plat = 'x64' if 'amd64' in plat_spec else 'x86'

    if best_dir:
        vcredist = join(best_dir, "..", "..", "redist", "MSVC", "**",
                        vcruntime_plat, "Microsoft.VC14*.CRT",
                        "vcruntime140.dll")
        try:
            import glob
            vcruntime = glob.glob(vcredist, recursive=True)[-1]
        except (ImportError, OSError, LookupError):
            vcruntime = None

    if not best_dir:
        best_version, best_dir = _msvc14_find_vc2015()
        if best_version:
            vcruntime = join(best_dir, 'redist', vcruntime_plat,
                             "Microsoft.VC140.CRT", "vcruntime140.dll")

    if not best_dir:
        return None, None

    vcvarsall = join(best_dir, "vcvarsall.bat")
    if not isfile(vcvarsall):
        return None, None

    if not vcruntime or not isfile(vcruntime):
        vcruntime = None

    return vcvarsall, vcruntime


def _msvc14_get_vc_env(plat_spec):
    """Python 3.8 "distutils/_msvccompiler.py" backport"""
    if "DISTUTILS_USE_SDK" in environ:
        return {
            key.lower(): value
            for key, value in environ.items()
        }

    vcvarsall, vcruntime = _msvc14_find_vcvarsall(plat_spec)
    if not vcvarsall:
        raise distutils.errors.DistutilsPlatformError(
            "Unable to find vcvarsall.bat"
        )

    try:
        out = subprocess.check_output(
            'cmd /u /c "{}" {} && set'.format(vcvarsall, plat_spec),
            stderr=subprocess.STDOUT,
        ).decode('utf-16le', errors='replace')
    except subprocess.CalledProcessError as exc:
        raise distutils.errors.DistutilsPlatformError(
            "Error executing {}".format(exc.cmd)
        ) from exc

    env = {
        key.lower(): value
        for key, _, value in
        (line.partition('=') for line in out.splitlines())
        if key and value
    }

    if vcruntime:
        env['py_vcruntime_redist'] = vcruntime
    return env


def msvc14_get_vc_env(plat_spec):
    """
    Patched "distutils._msvccompiler._get_vc_env" for support extra
    Microsoft Visual C++ 14.X compilers.

    Set environment without use of "vcvarsall.bat".

    Parameters
    ----------
    plat_spec: str
        Target architecture.

    Return
    ------
    dict
        environment
    """

    # Always use backport from CPython 3.8
    try:
        return _msvc14_get_vc_env(plat_spec)
    except distutils.errors.DistutilsPlatformError as exc:
        _augment_exception(exc, 14.0)
        raise


def msvc14_gen_lib_options(*args, **kwargs):
    """
    Patched "distutils._msvccompiler.gen_lib_options" for fix
    compatibility between "numpy.distutils" and "distutils._msvccompiler"
    (for Numpy < 1.11.2)
    """
    if "numpy.distutils" in sys.modules:
        import numpy as np
        if LegacyVersion(np.__version__) < LegacyVersion('1.11.2'):
            return np.distutils.ccompiler.gen_lib_options(*args, **kwargs)
    return get_unpatched(msvc14_gen_lib_options)(*args, **kwargs)


def _augment_exception(exc, version, arch=''):
    """
    Add details to the exception message to help guide the user
    as to what action will resolve it.
    """
    # Error if MSVC++ directory not found or environment not set
    message = exc.args[0]

    if "vcvarsall" in message.lower() or "visual c" in message.lower():
        # Special error message if MSVC++ not installed
        tmpl = 'Microsoft Visual C++ {version:0.1f} or greater is required.'
        message = tmpl.format(**locals())
        msdownload = 'www.microsoft.com/download/details.aspx?id=%d'
        if version == 9.0:
            if arch.lower().find('ia64') > -1:
                # For VC++ 9.0, if IA64 support is needed, redirect user
                # to Windows SDK 7.0.
                # Note: No download link available from Microsoft.
                message += ' Get it with "Microsoft Windows SDK 7.0"'
            else:
                # For VC++ 9.0 redirect user to Vc++ for Python 2.7 :
                # This redirection link is maintained by Microsoft.
                # Contact vspython@microsoft.com if it needs updating.
                message += ' Get it from http://aka.ms/vcpython27'
        elif version == 10.0:
            # For VC++ 10.0 Redirect user to Windows SDK 7.1
            message += ' Get it with "Microsoft Windows SDK 7.1": '
            message += msdownload % 8279
        elif version >= 14.0:
            # For VC++ 14.X Redirect user to latest Visual C++ Build Tools
            message += (' Get it with "Microsoft C++ Build Tools": '
                        r'https://visualstudio.microsoft.com'
                        r'/visual-cpp-build-tools/')

    exc.args = (message, )


class PlatformInfo:
    """
    Current and Target Architectures information.

    Parameters
    ----------
    arch: str
        Target architecture.
    """
    current_cpu = environ.get('processor_architecture', '').lower()

    def __init__(self, arch):
        self.arch = arch.lower().replace('x64', 'amd64')

    @property
    def target_cpu(self):
        """
        Return Target CPU architecture.

        Return
        ------
        str
            Target CPU
        """
        return self.arch[self.arch.find('_') + 1:]

    def target_is_x86(self):
        """
        Return True if target CPU is x86 32 bits..

        Return
        ------
        bool
            CPU is x86 32 bits
        """
        return self.target_cpu == 'x86'

    def current_is_x86(self):
        """
        Return True if current CPU is x86 32 bits..

        Return
        ------
        bool
            CPU is x86 32 bits
        """
        return self.current_cpu == 'x86'

    def current_dir(self, hidex86=False, x64=False):
        """
        Current platform specific subfolder.

        Parameters
        ----------
        hidex86: bool
            return '' and not '\x86' if architecture is x86.
        x64: bool
            return '\x64' and not '\amd64' if architecture is amd64.

        Return
        ------
        str
            subfolder: '\target', or '' (see hidex86 parameter)
        """
        return (
            '' if (self.current_cpu == 'x86' and hidex86) else
            r'\x64' if (self.current_cpu == 'amd64' and x64) else
            r'\%s' % self.current_cpu
        )

    def target_dir(self, hidex86=False, x64=False):
        r"""
        Target platform specific subfolder.

        Parameters
        ----------
        hidex86: bool
            return '' and not '\x86' if architecture is x86.
        x64: bool
            return '\x64' and not '\amd64' if architecture is amd64.

        Return
        ------
        str
            subfolder: '\current', or '' (see hidex86 parameter)
        """
        return (
            '' if (self.target_cpu == 'x86' and hidex86) else
            r'\x64' if (self.target_cpu == 'amd64' and x64) else
            r'\%s' % self.target_cpu
        )

    def cross_dir(self, forcex86=False):
        r"""
        Cross platform specific subfolder.

        Parameters
        ----------
        forcex86: bool
            Use 'x86' as current architecture even if current architecture is
            not x86.

        Return
        ------
        str
            subfolder: '' if target architecture is current architecture,
            '\current_target' if not.
        """
        current = 'x86' if forcex86 else self.current_cpu
        return (
            '' if self.target_cpu == current else
            self.target_dir().replace('\\', '\\%s_' % current)
        )


class RegistryInfo:
    """
    Microsoft Visual Studio related registry information.

    Parameters
    ----------
    platform_info: PlatformInfo
        "PlatformInfo" instance.
    """
    HKEYS = (winreg.HKEY_USERS,
             winreg.HKEY_CURRENT_USER,
             winreg.HKEY_LOCAL_MACHINE,
             winreg.HKEY_CLASSES_ROOT)

    def __init__(self, platform_info):
        self.pi = platform_info

    @property
    def visualstudio(self):
        """
        Microsoft Visual Studio root registry key.

        Return
        ------
        str
            Registry key
        """
        return 'VisualStudio'

    @property
    def sxs(self):
        """
        Microsoft Visual Studio SxS registry key.

        Return
        ------
        str
            Registry key
        """
        return join(self.visualstudio, 'SxS')

    @property
    def vc(self):
        """
        Microsoft Visual C++ VC7 registry key.

        Return
        ------
        str
            Registry key
        """
        return join(self.sxs, 'VC7')

    @property
    def vs(self):
        """
        Microsoft Visual Studio VS7 registry key.

        Return
        ------
        str
            Registry key
        """
        return join(self.sxs, 'VS7')

    @property
    def vc_for_python(self):
        """
        Microsoft Visual C++ for Python registry key.

        Return
        ------
        str
            Registry key
        """
        return r'DevDiv\VCForPython'

    @property
    def microsoft_sdk(self):
        """
        Microsoft SDK registry key.

        Return
        ------
        str
            Registry key
        """
        return 'Microsoft SDKs'

    @property
    def windows_sdk(self):
        """
        Microsoft Windows/Platform SDK registry key.

        Return
        ------
        str
            Registry key
        """
        return join(self.microsoft_sdk, 'Windows')

    @property
    def netfx_sdk(self):
        """
        Microsoft .NET Framework SDK registry key.

        Return
        ------
        str
            Registry key
        """
        return join(self.microsoft_sdk, 'NETFXSDK')

    @property
    def windows_kits_roots(self):
        """
        Microsoft Windows Kits Roots registry key.

        Return
        ------
        str
            Registry key
        """
        return r'Windows Kits\Installed Roots'

    def microsoft(self, key, x86=False):
        """
        Return key in Microsoft software registry.

        Parameters
        ----------
        key: str
            Registry key path where look.
        x86: str
            Force x86 software registry.

        Return
        ------
        str
            Registry key
        """
        node64 = '' if self.pi.current_is_x86() or x86 else 'Wow6432Node'
        return join('Software', node64, 'Microsoft', key)

    def lookup(self, key, name):
        """
        Look for values in registry in Microsoft software registry.

        Parameters
        ----------
        key: str
            Registry key path where look.
        name: str
            Value name to find.

        Return
        ------
        str
            value
        """
        key_read = winreg.KEY_READ
        openkey = winreg.OpenKey
        closekey = winreg.CloseKey
        ms = self.microsoft
        for hkey in self.HKEYS:
            bkey = None
            try:
                bkey = openkey(hkey, ms(key), 0, key_read)
            except (OSError, IOError):
                if not self.pi.current_is_x86():
                    try:
                        bkey = openkey(hkey, ms(key, True), 0, key_read)
                    except (OSError, IOError):
                        continue
                else:
                    continue
            try:
                return winreg.QueryValueEx(bkey, name)[0]
            except (OSError, IOError):
                pass
            finally:
                if bkey:
                    closekey(bkey)


class SystemInfo:
    """
    Microsoft Windows and Visual Studio related system information.

    Parameters
    ----------
    registry_info: RegistryInfo
        "RegistryInfo" instance.
    vc_ver: float
        Required Microsoft Visual C++ version.
    """

    # Variables and properties in this class use originals CamelCase variables
    # names from Microsoft source files for more easy comparison.
    WinDir = environ.get('WinDir', '')
    ProgramFiles = environ.get('ProgramFiles', '')
    ProgramFilesx86 = environ.get('ProgramFiles(x86)', ProgramFiles)

    def __init__(self, registry_info, vc_ver=None):
        self.ri = registry_info
        self.pi = self.ri.pi

        self.known_vs_paths = self.find_programdata_vs_vers()

        # Except for VS15+, VC version is aligned with VS version
        self.vs_ver = self.vc_ver = (
            vc_ver or self._find_latest_available_vs_ver())

    def _find_latest_available_vs_ver(self):
        """
        Find the latest VC version

        Return
        ------
        float
            version
        """
        reg_vc_vers = self.find_reg_vs_vers()

        if not (reg_vc_vers or self.known_vs_paths):
            raise distutils.errors.DistutilsPlatformError(
                'No Microsoft Visual C++ version found')

        vc_vers = set(reg_vc_vers)
        vc_vers.update(self.known_vs_paths)
        return sorted(vc_vers)[-1]

    def find_reg_vs_vers(self):
        """
        Find Microsoft Visual Studio versions available in registry.

        Return
        ------
        list of float
            Versions
        """
        ms = self.ri.microsoft
        vckeys = (self.ri.vc, self.ri.vc_for_python, self.ri.vs)
        vs_vers = []
        for hkey in self.ri.HKEYS:
            for key in vckeys:
                try:
                    bkey = winreg.OpenKey(hkey, ms(key), 0, winreg.KEY_READ)
                except (OSError, IOError):
                    continue
                with bkey:
                    subkeys, values, _ = winreg.QueryInfoKey(bkey)
                    for i in range(values):
                        try:
                            ver = float(winreg.EnumValue(bkey, i)[0])
                            if ver not in vs_vers:
                                vs_vers.append(ver)
                        except ValueError:
                            pass
                    for i in range(subkeys):
                        try:
                            ver = float(winreg.EnumKey(bkey, i))
                            if ver not in vs_vers:
                                vs_vers.append(ver)
                        except ValueError:
                            pass
        return sorted(vs_vers)

    def find_programdata_vs_vers(self):
        r"""
        Find Visual studio 2017+ versions from information in
        "C:\ProgramData\Microsoft\VisualStudio\Packages\_Instances".

        Return
        ------
        dict
            float version as key, path as value.
        """
        vs_versions = {}
        instances_dir = \
            r'C:\ProgramData\Microsoft\VisualStudio\Packages\_Instances'

        try:
            hashed_names = listdir(instances_dir)

        except (OSError, IOError):
            # Directory not exists with all Visual Studio versions
            return vs_versions

        for name in hashed_names:
            try:
                # Get VS installation path from "state.json" file
                state_path = join(instances_dir, name, 'state.json')
                with open(state_path, 'rt', encoding='utf-8') as state_file:
                    state = json.load(state_file)
                vs_path = state['installationPath']

                # Raises OSError if this VS installation does not contain VC
                listdir(join(vs_path, r'VC\Tools\MSVC'))

                # Store version and path
                vs_versions[self._as_float_version(
                    state['installationVersion'])] = vs_path

            except (OSError, IOError, KeyError):
                # Skip if "state.json" file is missing or bad format
                continue

        return vs_versions

    @staticmethod
    def _as_float_version(version):
        """
        Return a string version as a simplified float version (major.minor)

        Parameters
        ----------
        version: str
            Version.

        Return
        ------
        float
            version
        """
        return float('.'.join(version.split('.')[:2]))

    @property
    def VSInstallDir(self):
        """
        Microsoft Visual Studio directory.

        Return
        ------
        str
            path
        """
        # Default path
        default = join(self.ProgramFilesx86,
                       'Microsoft Visual Studio %0.1f' % self.vs_ver)

        # Try to get path from registry, if fail use default path
        return self.ri.lookup(self.ri.vs, '%0.1f' % self.vs_ver) or default

    @property
    def VCInstallDir(self):
        """
        Microsoft Visual C++ directory.

        Return
        ------
        str
            path
        """
        path = self._guess_vc() or self._guess_vc_legacy()

        if not isdir(path):
            msg = 'Microsoft Visual C++ directory not found'
            raise distutils.errors.DistutilsPlatformError(msg)

        return path

    def _guess_vc(self):
        """
        Locate Visual C++ for VS2017+.

        Return
        ------
        str
            path
        """
        if self.vs_ver <= 14.0:
            return ''

        try:
            # First search in known VS paths
            vs_dir = self.known_vs_paths[self.vs_ver]
        except KeyError:
            # Else, search with path from registry
            vs_dir = self.VSInstallDir

        guess_vc = join(vs_dir, r'VC\Tools\MSVC')

        # Subdir with VC exact version as name
        try:
            # Update the VC version with real one instead of VS version
            vc_ver = listdir(guess_vc)[-1]
            self.vc_ver = self._as_float_version(vc_ver)
            return join(guess_vc, vc_ver)
        except (OSError, IOError, IndexError):
            return ''

    def _guess_vc_legacy(self):
        """
        Locate Visual C++ for versions prior to 2017.

        Return
        ------
        str
            path
        """
        default = join(self.ProgramFilesx86,
                       r'Microsoft Visual Studio %0.1f\VC' % self.vs_ver)

        # Try to get "VC++ for Python" path from registry as default path
        reg_path = join(self.ri.vc_for_python, '%0.1f' % self.vs_ver)
        python_vc = self.ri.lookup(reg_path, 'installdir')
        default_vc = join(python_vc, 'VC') if python_vc else default

        # Try to get path from registry, if fail use default path
        return self.ri.lookup(self.ri.vc, '%0.1f' % self.vs_ver) or default_vc

    @property
    def WindowsSdkVersion(self):
        """
        Microsoft Windows SDK versions for specified MSVC++ version.

        Return
        ------
        tuple of str
            versions
        """
        if self.vs_ver <= 9.0:
            return '7.0', '6.1', '6.0a'
        elif self.vs_ver == 10.0:
            return '7.1', '7.0a'
        elif self.vs_ver == 11.0:
            return '8.0', '8.0a'
        elif self.vs_ver == 12.0:
            return '8.1', '8.1a'
        elif self.vs_ver >= 14.0:
            return '10.0', '8.1'

    @property
    def WindowsSdkLastVersion(self):
        """
        Microsoft Windows SDK last version.

        Return
        ------
        str
            version
        """
        return self._use_last_dir_name(join(self.WindowsSdkDir, 'lib'))

    @property
    def WindowsSdkDir(self):
        """
        Microsoft Windows SDK directory.

        Return
        ------
        str
            path
        """
        sdkdir = ''
        for ver in self.WindowsSdkVersion:
            # Try to get it from registry
            loc = join(self.ri.windows_sdk, 'v%s' % ver)
            sdkdir = self.ri.lookup(loc, 'installationfolder')
            if sdkdir:
                break
        if not sdkdir or not isdir(sdkdir):
            # Try to get "VC++ for Python" version from registry
            path = join(self.ri.vc_for_python, '%0.1f' % self.vc_ver)
            install_base = self.ri.lookup(path, 'installdir')
            if install_base:
                sdkdir = join(install_base, 'WinSDK')
        if not sdkdir or not isdir(sdkdir):
            # If fail, use default new path
            for ver in self.WindowsSdkVersion:
                intver = ver[:ver.rfind('.')]
                path = r'Microsoft SDKs\Windows Kits\%s' % intver
                d = join(self.ProgramFiles, path)
                if isdir(d):
                    sdkdir = d
        if not sdkdir or not isdir(sdkdir):
            # If fail, use default old path
            for ver in self.WindowsSdkVersion:
                path = r'Microsoft SDKs\Windows\v%s' % ver
                d = join(self.ProgramFiles, path)
                if isdir(d):
                    sdkdir = d
        if not sdkdir:
            # If fail, use Platform SDK
            sdkdir = join(self.VCInstallDir, 'PlatformSDK')
        return sdkdir

    @property
    def WindowsSDKExecutablePath(self):
        """
        Microsoft Windows SDK executable directory.

        Return
        ------
        str
            path
        """
        # Find WinSDK NetFx Tools registry dir name
        if self.vs_ver <= 11.0:
            netfxver = 35
            arch = ''
        else:
            netfxver = 40
            hidex86 = True if self.vs_ver <= 12.0 else False
            arch = self.pi.current_dir(x64=True, hidex86=hidex86)
        fx = 'WinSDK-NetFx%dTools%s' % (netfxver, arch.replace('\\', '-'))

        # list all possibles registry paths
        regpaths = []
        if self.vs_ver >= 14.0:
            for ver in self.NetFxSdkVersion:
                regpaths += [join(self.ri.netfx_sdk, ver, fx)]

        for ver in self.WindowsSdkVersion:
            regpaths += [join(self.ri.windows_sdk, 'v%sA' % ver, fx)]

        # Return installation folder from the more recent path
        for path in regpaths:
            execpath = self.ri.lookup(path, 'installationfolder')
            if execpath:
                return execpath

    @property
    def FSharpInstallDir(self):
        """
        Microsoft Visual F# directory.

        Return
        ------
        str
            path
        """
        path = join(self.ri.visualstudio, r'%0.1f\Setup\F#' % self.vs_ver)
        return self.ri.lookup(path, 'productdir') or ''

    @property
    def UniversalCRTSdkDir(self):
        """
        Microsoft Universal CRT SDK directory.

        Return
        ------
        str
            path
        """
        # Set Kit Roots versions for specified MSVC++ version
        vers = ('10', '81') if self.vs_ver >= 14.0 else ()

        # Find path of the more recent Kit
        for ver in vers:
            sdkdir = self.ri.lookup(self.ri.windows_kits_roots,
                                    'kitsroot%s' % ver)
            if sdkdir:
                return sdkdir or ''

    @property
    def UniversalCRTSdkLastVersion(self):
        """
        Microsoft Universal C Runtime SDK last version.

        Return
        ------
        str
            version
        """
        return self._use_last_dir_name(join(self.UniversalCRTSdkDir, 'lib'))

    @property
    def NetFxSdkVersion(self):
        """
        Microsoft .NET Framework SDK versions.

        Return
        ------
        tuple of str
            versions
        """
        # Set FxSdk versions for specified VS version
        return (('4.7.2', '4.7.1', '4.7',
                 '4.6.2', '4.6.1', '4.6',
                 '4.5.2', '4.5.1', '4.5')
                if self.vs_ver >= 14.0 else ())

    @property
    def NetFxSdkDir(self):
        """
        Microsoft .NET Framework SDK directory.

        Return
        ------
        str
            path
        """
        sdkdir = ''
        for ver in self.NetFxSdkVersion:
            loc = join(self.ri.netfx_sdk, ver)
            sdkdir = self.ri.lookup(loc, 'kitsinstallationfolder')
            if sdkdir:
                break
        return sdkdir

    @property
    def FrameworkDir32(self):
        """
        Microsoft .NET Framework 32bit directory.

        Return
        ------
        str
            path
        """
        # Default path
        guess_fw = join(self.WinDir, r'Microsoft.NET\Framework')

        # Try to get path from registry, if fail use default path
        return self.ri.lookup(self.ri.vc, 'frameworkdir32') or guess_fw

    @property
    def FrameworkDir64(self):
        """
        Microsoft .NET Framework 64bit directory.

        Return
        ------
        str
            path
        """
        # Default path
        guess_fw = join(self.WinDir, r'Microsoft.NET\Framework64')

        # Try to get path from registry, if fail use default path
        return self.ri.lookup(self.ri.vc, 'frameworkdir64') or guess_fw

    @property
    def FrameworkVersion32(self):
        """
        Microsoft .NET Framework 32bit versions.

        Return
        ------
        tuple of str
            versions
        """
        return self._find_dot_net_versions(32)

    @property
    def FrameworkVersion64(self):
        """
        Microsoft .NET Framework 64bit versions.

        Return
        ------
        tuple of str
            versions
        """
        return self._find_dot_net_versions(64)

    def _find_dot_net_versions(self, bits):
        """
        Find Microsoft .NET Framework versions.

        Parameters
        ----------
        bits: int
            Platform number of bits: 32 or 64.

        Return
        ------
        tuple of str
            versions
        """
        # Find actual .NET version in registry
        reg_ver = self.ri.lookup(self.ri.vc, 'frameworkver%d' % bits)
        dot_net_dir = getattr(self, 'FrameworkDir%d' % bits)
        ver = reg_ver or self._use_last_dir_name(dot_net_dir, 'v') or ''

        # Set .NET versions for specified MSVC++ version
        if self.vs_ver >= 12.0:
            return ver, 'v4.0'
        elif self.vs_ver >= 10.0:
            return 'v4.0.30319' if ver.lower()[:2] != 'v4' else ver, 'v3.5'
        elif self.vs_ver == 9.0:
            return 'v3.5', 'v2.0.50727'
        elif self.vs_ver == 8.0:
            return 'v3.0', 'v2.0.50727'

    @staticmethod
    def _use_last_dir_name(path, prefix=''):
        """
        Return name of the last dir in path or '' if no dir found.

        Parameters
        ----------
        path: str
            Use dirs in this path
        prefix: str
            Use only dirs starting by this prefix

        Return
        ------
        str
            name
        """
        matching_dirs = (
            dir_name
            for dir_name in reversed(listdir(path))
            if isdir(join(path, dir_name)) and
            dir_name.startswith(prefix)
        )
        return next(matching_dirs, None) or ''


class EnvironmentInfo:
    """
    Return environment variables for specified Microsoft Visual C++ version
    and platform : Lib, Include, Path and libpath.

    This function is compatible with Microsoft Visual C++ 9.0 to 14.X.

    Script created by analysing Microsoft environment configuration files like
    "vcvars[...].bat", "SetEnv.Cmd", "vcbuildtools.bat", ...

    Parameters
    ----------
    arch: str
        Target architecture.
    vc_ver: float
        Required Microsoft Visual C++ version. If not set, autodetect the last
        version.
    vc_min_ver: float
        Minimum Microsoft Visual C++ version.
    """

    # Variables and properties in this class use originals CamelCase variables
    # names from Microsoft source files for more easy comparison.

    def __init__(self, arch, vc_ver=None, vc_min_ver=0):
        self.pi = PlatformInfo(arch)
        self.ri = RegistryInfo(self.pi)
        self.si = SystemInfo(self.ri, vc_ver)

        if self.vc_ver < vc_min_ver:
            err = 'No suitable Microsoft Visual C++ version found'
            raise distutils.errors.DistutilsPlatformError(err)

    @property
    def vs_ver(self):
        """
        Microsoft Visual Studio.

        Return
        ------
        float
            version
        """
        return self.si.vs_ver

    @property
    def vc_ver(self):
        """
        Microsoft Visual C++ version.

        Return
        ------
        float
            version
        """
        return self.si.vc_ver

    @property
    def VSTools(self):
        """
        Microsoft Visual Studio Tools.

        Return
        ------
        list of str
            paths
        """
        paths = [r'Common7\IDE', r'Common7\Tools']

        if self.vs_ver >= 14.0:
            arch_subdir = self.pi.current_dir(hidex86=True, x64=True)
            paths += [r'Common7\IDE\CommonExtensions\Microsoft\TestWindow']
            paths += [r'Team Tools\Performance Tools']
            paths += [r'Team Tools\Performance Tools%s' % arch_subdir]

        return [join(self.si.VSInstallDir, path) for path in paths]

    @property
    def VCIncludes(self):
        """
        Microsoft Visual C++ & Microsoft Foundation Class Includes.

        Return
        ------
        list of str
            paths
        """
        return [join(self.si.VCInstallDir, 'Include'),
                join(self.si.VCInstallDir, r'ATLMFC\Include')]

    @property
    def VCLibraries(self):
        """
        Microsoft Visual C++ & Microsoft Foundation Class Libraries.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver >= 15.0:
            arch_subdir = self.pi.target_dir(x64=True)
        else:
            arch_subdir = self.pi.target_dir(hidex86=True)
        paths = ['Lib%s' % arch_subdir, r'ATLMFC\Lib%s' % arch_subdir]

        if self.vs_ver >= 14.0:
            paths += [r'Lib\store%s' % arch_subdir]

        return [join(self.si.VCInstallDir, path) for path in paths]

    @property
    def VCStoreRefs(self):
        """
        Microsoft Visual C++ store references Libraries.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver < 14.0:
            return []
        return [join(self.si.VCInstallDir, r'Lib\store\references')]

    @property
    def VCTools(self):
        """
        Microsoft Visual C++ Tools.

        Return
        ------
        list of str
            paths
        """
        si = self.si
        tools = [join(si.VCInstallDir, 'VCPackages')]

        forcex86 = True if self.vs_ver <= 10.0 else False
        arch_subdir = self.pi.cross_dir(forcex86)
        if arch_subdir:
            tools += [join(si.VCInstallDir, 'Bin%s' % arch_subdir)]

        if self.vs_ver == 14.0:
            path = 'Bin%s' % self.pi.current_dir(hidex86=True)
            tools += [join(si.VCInstallDir, path)]

        elif self.vs_ver >= 15.0:
            host_dir = (r'bin\HostX86%s' if self.pi.current_is_x86() else
                        r'bin\HostX64%s')
            tools += [join(
                si.VCInstallDir, host_dir % self.pi.target_dir(x64=True))]

            if self.pi.current_cpu != self.pi.target_cpu:
                tools += [join(
                    si.VCInstallDir, host_dir % self.pi.current_dir(x64=True))]

        else:
            tools += [join(si.VCInstallDir, 'Bin')]

        return tools

    @property
    def OSLibraries(self):
        """
        Microsoft Windows SDK Libraries.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver <= 10.0:
            arch_subdir = self.pi.target_dir(hidex86=True, x64=True)
            return [join(self.si.WindowsSdkDir, 'Lib%s' % arch_subdir)]

        else:
            arch_subdir = self.pi.target_dir(x64=True)
            lib = join(self.si.WindowsSdkDir, 'lib')
            libver = self._sdk_subdir
            return [join(lib, '%sum%s' % (libver, arch_subdir))]

    @property
    def OSIncludes(self):
        """
        Microsoft Windows SDK Include.

        Return
        ------
        list of str
            paths
        """
        include = join(self.si.WindowsSdkDir, 'include')

        if self.vs_ver <= 10.0:
            return [include, join(include, 'gl')]

        else:
            if self.vs_ver >= 14.0:
                sdkver = self._sdk_subdir
            else:
                sdkver = ''
            return [join(include, '%sshared' % sdkver),
                    join(include, '%sum' % sdkver),
                    join(include, '%swinrt' % sdkver)]

    @property
    def OSLibpath(self):
        """
        Microsoft Windows SDK Libraries Paths.

        Return
        ------
        list of str
            paths
        """
        ref = join(self.si.WindowsSdkDir, 'References')
        libpath = []

        if self.vs_ver <= 9.0:
            libpath += self.OSLibraries

        if self.vs_ver >= 11.0:
            libpath += [join(ref, r'CommonConfiguration\Neutral')]

        if self.vs_ver >= 14.0:
            libpath += [
                ref,
                join(self.si.WindowsSdkDir, 'UnionMetadata'),
                join(
                    ref, 'Windows.Foundation.UniversalApiContract', '1.0.0.0'),
                join(ref, 'Windows.Foundation.FoundationContract', '1.0.0.0'),
                join(
                    ref, 'Windows.Networking.Connectivity.WwanContract',
                    '1.0.0.0'),
                join(
                    self.si.WindowsSdkDir, 'ExtensionSDKs', 'Microsoft.VCLibs',
                    '%0.1f' % self.vs_ver, 'References', 'CommonConfiguration',
                    'neutral'),
            ]
        return libpath

    @property
    def SdkTools(self):
        """
        Microsoft Windows SDK Tools.

        Return
        ------
        list of str
            paths
        """
        return list(self._sdk_tools())

    def _sdk_tools(self):
        """
        Microsoft Windows SDK Tools paths generator.

        Return
        ------
        generator of str
            paths
        """
        if self.vs_ver < 15.0:
            bin_dir = 'Bin' if self.vs_ver <= 11.0 else r'Bin\x86'
            yield join(self.si.WindowsSdkDir, bin_dir)

        if not self.pi.current_is_x86():
            arch_subdir = self.pi.current_dir(x64=True)
            path = 'Bin%s' % arch_subdir
            yield join(self.si.WindowsSdkDir, path)

        if self.vs_ver in (10.0, 11.0):
            if self.pi.target_is_x86():
                arch_subdir = ''
            else:
                arch_subdir = self.pi.current_dir(hidex86=True, x64=True)
            path = r'Bin\NETFX 4.0 Tools%s' % arch_subdir
            yield join(self.si.WindowsSdkDir, path)

        elif self.vs_ver >= 15.0:
            path = join(self.si.WindowsSdkDir, 'Bin')
            arch_subdir = self.pi.current_dir(x64=True)
            sdkver = self.si.WindowsSdkLastVersion
            yield join(path, '%s%s' % (sdkver, arch_subdir))

        if self.si.WindowsSDKExecutablePath:
            yield self.si.WindowsSDKExecutablePath

    @property
    def _sdk_subdir(self):
        """
        Microsoft Windows SDK version subdir.

        Return
        ------
        str
            subdir
        """
        ucrtver = self.si.WindowsSdkLastVersion
        return ('%s\\' % ucrtver) if ucrtver else ''

    @property
    def SdkSetup(self):
        """
        Microsoft Windows SDK Setup.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver > 9.0:
            return []

        return [join(self.si.WindowsSdkDir, 'Setup')]

    @property
    def FxTools(self):
        """
        Microsoft .NET Framework Tools.

        Return
        ------
        list of str
            paths
        """
        pi = self.pi
        si = self.si

        if self.vs_ver <= 10.0:
            include32 = True
            include64 = not pi.target_is_x86() and not pi.current_is_x86()
        else:
            include32 = pi.target_is_x86() or pi.current_is_x86()
            include64 = pi.current_cpu == 'amd64' or pi.target_cpu == 'amd64'

        tools = []
        if include32:
            tools += [join(si.FrameworkDir32, ver)
                      for ver in si.FrameworkVersion32]
        if include64:
            tools += [join(si.FrameworkDir64, ver)
                      for ver in si.FrameworkVersion64]
        return tools

    @property
    def NetFxSDKLibraries(self):
        """
        Microsoft .Net Framework SDK Libraries.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver < 14.0 or not self.si.NetFxSdkDir:
            return []

        arch_subdir = self.pi.target_dir(x64=True)
        return [join(self.si.NetFxSdkDir, r'lib\um%s' % arch_subdir)]

    @property
    def NetFxSDKIncludes(self):
        """
        Microsoft .Net Framework SDK Includes.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver < 14.0 or not self.si.NetFxSdkDir:
            return []

        return [join(self.si.NetFxSdkDir, r'include\um')]

    @property
    def VsTDb(self):
        """
        Microsoft Visual Studio Team System Database.

        Return
        ------
        list of str
            paths
        """
        return [join(self.si.VSInstallDir, r'VSTSDB\Deploy')]

    @property
    def MSBuild(self):
        """
        Microsoft Build Engine.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver < 12.0:
            return []
        elif self.vs_ver < 15.0:
            base_path = self.si.ProgramFilesx86
            arch_subdir = self.pi.current_dir(hidex86=True)
        else:
            base_path = self.si.VSInstallDir
            arch_subdir = ''

        path = r'MSBuild\%0.1f\bin%s' % (self.vs_ver, arch_subdir)
        build = [join(base_path, path)]

        if self.vs_ver >= 15.0:
            # Add Roslyn C# & Visual Basic Compiler
            build += [join(base_path, path, 'Roslyn')]

        return build

    @property
    def HTMLHelpWorkshop(self):
        """
        Microsoft HTML Help Workshop.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver < 11.0:
            return []

        return [join(self.si.ProgramFilesx86, 'HTML Help Workshop')]

    @property
    def UCRTLibraries(self):
        """
        Microsoft Universal C Runtime SDK Libraries.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver < 14.0:
            return []

        arch_subdir = self.pi.target_dir(x64=True)
        lib = join(self.si.UniversalCRTSdkDir, 'lib')
        ucrtver = self._ucrt_subdir
        return [join(lib, '%sucrt%s' % (ucrtver, arch_subdir))]

    @property
    def UCRTIncludes(self):
        """
        Microsoft Universal C Runtime SDK Include.

        Return
        ------
        list of str
            paths
        """
        if self.vs_ver < 14.0:
            return []

        include = join(self.si.UniversalCRTSdkDir, 'include')
        return [join(include, '%sucrt' % self._ucrt_subdir)]

    @property
    def _ucrt_subdir(self):
        """
        Microsoft Universal C Runtime SDK version subdir.

        Return
        ------
        str
            subdir
        """
        ucrtver = self.si.UniversalCRTSdkLastVersion
        return ('%s\\' % ucrtver) if ucrtver else ''

    @property
    def FSharp(self):
        """
        Microsoft Visual F#.

        Return
        ------
        list of str
            paths
        """
        if 11.0 > self.vs_ver > 12.0:
            return []

        return [self.si.FSharpInstallDir]

    @property
    def VCRuntimeRedist(self):
        """
        Microsoft Visual C++ runtime redistributable dll.

        Return
        ------
        str
            path
        """
        vcruntime = 'vcruntime%d0.dll' % self.vc_ver
        arch_subdir = self.pi.target_dir(x64=True).strip('\\')

        # Installation prefixes candidates
        prefixes = []
        tools_path = self.si.VCInstallDir
        redist_path = dirname(tools_path.replace(r'\Tools', r'\Redist'))
        if isdir(redist_path):
            # Redist version may not be exactly the same as tools
            redist_path = join(redist_path, listdir(redist_path)[-1])
            prefixes += [redist_path, join(redist_path, 'onecore')]

        prefixes += [join(tools_path, 'redist')]  # VS14 legacy path

        # CRT directory
        crt_dirs = ('Microsoft.VC%d.CRT' % (self.vc_ver * 10),
                    # Sometime store in directory with VS version instead of VC
                    'Microsoft.VC%d.CRT' % (int(self.vs_ver) * 10))

        # vcruntime path
        for prefix, crt_dir in itertools.product(prefixes, crt_dirs):
            path = join(prefix, arch_subdir, crt_dir, vcruntime)
            if isfile(path):
                return path

    def return_env(self, exists=True):
        """
        Return environment dict.

        Parameters
        ----------
        exists: bool
            It True, only return existing paths.

        Return
        ------
        dict
            environment
        """
        env = dict(
            include=self._build_paths('include',
                                      [self.VCIncludes,
                                       self.OSIncludes,
                                       self.UCRTIncludes,
                                       self.NetFxSDKIncludes],
                                      exists),
            lib=self._build_paths('lib',
                                  [self.VCLibraries,
                                   self.OSLibraries,
                                   self.FxTools,
                                   self.UCRTLibraries,
                                   self.NetFxSDKLibraries],
                                  exists),
            libpath=self._build_paths('libpath',
                                      [self.VCLibraries,
                                       self.FxTools,
                                       self.VCStoreRefs,
                                       self.OSLibpath],
                                      exists),
            path=self._build_paths('path',
                                   [self.VCTools,
                                    self.VSTools,
                                    self.VsTDb,
                                    self.SdkTools,
                                    self.SdkSetup,
                                    self.FxTools,
                                    self.MSBuild,
                                    self.HTMLHelpWorkshop,
                                    self.FSharp],
                                   exists),
        )
        if self.vs_ver >= 14 and isfile(self.VCRuntimeRedist):
            env['py_vcruntime_redist'] = self.VCRuntimeRedist
        return env

    def _build_paths(self, name, spec_path_lists, exists):
        """
        Given an environment variable name and specified paths,
        return a pathsep-separated string of paths containing
        unique, extant, directories from those paths and from
        the environment variable. Raise an error if no paths
        are resolved.

        Parameters
        ----------
        name: str
            Environment variable name
        spec_path_lists: list of str
            Paths
        exists: bool
            It True, only return existing paths.

        Return
        ------
        str
            Pathsep-separated paths
        """
        # flatten spec_path_lists
        spec_paths = itertools.chain.from_iterable(spec_path_lists)
        env_paths = environ.get(name, '').split(pathsep)
        paths = itertools.chain(spec_paths, env_paths)
        extant_paths = list(filter(isdir, paths)) if exists else paths
        if not extant_paths:
            msg = "%s environment variable is empty" % name.upper()
            raise distutils.errors.DistutilsPlatformError(msg)
        unique_paths = self._unique_everseen(extant_paths)
        return pathsep.join(unique_paths)

    # from Python docs
    @staticmethod
    def _unique_everseen(iterable, key=None):
        """
        List unique elements, preserving order.
        Remember all elements ever seen.

        _unique_everseen('AAAABBBCCDAABBB') --> A B C D

        _unique_everseen('ABBCcAD', str.lower) --> A B C D
        """
        seen = set()
        seen_add = seen.add
        if key is None:
            for element in itertools.filterfalse(seen.__contains__, iterable):
                seen_add(element)
                yield element
        else:
            for element in iterable:
                k = key(element)
                if k not in seen:
                    seen_add(k)
                    yield element
