# -*- coding: utf-8 -*-
'''
Create virtualenv environments.

.. versionadded:: 0.17.0
'''

# Import python libs
from __future__ import absolute_import, print_function, unicode_literals
import glob
import shutil
import logging
import os
import sys

# Import salt libs
import salt.utils.files
import salt.utils.path
import salt.utils.platform
import salt.utils.verify
from salt.exceptions import CommandExecutionError, SaltInvocationError
from salt.ext.six import string_types

KNOWN_BINARY_NAMES = frozenset([
    'virtualenv-{0}.{1}'.format(*sys.version_info[:2]),
    'virtualenv{0}'.format(sys.version_info[0]),
    'virtualenv',
])

log = logging.getLogger(__name__)

__opts__ = {
    'venv_bin': salt.utils.path.which_bin(KNOWN_BINARY_NAMES) or 'virtualenv'
}

__pillar__ = {}

# Define the module's virtual name
__virtualname__ = 'virtualenv'


def __virtual__():
    return __virtualname__


def virtualenv_ver(venv_bin, user=None, **kwargs):
    '''
    return virtualenv version if exists
    '''
    # Virtualenv package
    try:
        import virtualenv
        version = getattr(virtualenv, '__version__', None)
        if not version:
            version = virtualenv.virtualenv_version
        virtualenv_version_info = tuple(
            [int(i) for i in version.split('rc')[0].split('.')]
        )
    except ImportError:
        # Unable to import?? Let's parse the version from the console
        version_cmd = [venv_bin, '--version']
        ret = __salt__['cmd.run_all'](
                version_cmd, runas=user, python_shell=False, **kwargs
            )
        if ret['retcode'] > 0 or not ret['stdout'].strip():
            raise CommandExecutionError(
                'Unable to get the virtualenv version output using \'{0}\'. '
                'Returned data: {1}'.format(version_cmd, ret)
            )
        virtualenv_version_info = tuple(
            [int(i) for i in
             ret['stdout'].strip().split('rc')[0].split('.')]
        )
    return virtualenv_version_info


def create(path,
           venv_bin=None,
           system_site_packages=False,
           distribute=False,
           clear=False,
           python=None,
           extra_search_dir=None,
           never_download=None,
           prompt=None,
           pip=False,
           symlinks=None,
           upgrade=None,
           user=None,
           use_vt=False,
           saltenv='base',
           **kwargs):
    '''
    Create a virtualenv

    path
        The path to the virtualenv to be created

    venv_bin
        The name (and optionally path) of the virtualenv command. This can also
        be set globally in the minion config file as ``virtualenv.venv_bin``.
        Defaults to ``virtualenv``.

    system_site_packages : False
        Passthrough argument given to virtualenv or pyvenv

    distribute : False
        Passthrough argument given to virtualenv

    pip : False
        Install pip after creating a virtual environment. Implies
        ``distribute=True``

    clear : False
        Passthrough argument given to virtualenv or pyvenv

    python : None (default)
        Passthrough argument given to virtualenv

    extra_search_dir : None (default)
        Passthrough argument given to virtualenv

    never_download : None (default)
        Passthrough argument given to virtualenv if True

    prompt : None (default)
        Passthrough argument given to virtualenv if not None

    symlinks : None
        Passthrough argument given to pyvenv if True

    upgrade : None
        Passthrough argument given to pyvenv if True

    user : None
        Set ownership for the virtualenv

        .. note::
            On Windows you must also pass a ``password`` parameter. Additionally,
            the user must have permissions to the location where the virtual
            environment is being created

    runas : None
        Set ownership for the virtualenv

        .. deprecated:: 2014.1.0
            ``user`` should be used instead

    use_vt : False
        Use VT terminal emulation (see output while installing)

        .. versionadded:: 2015.5.0

    saltenv : 'base'
        Specify a different environment. The default environment is ``base``.

        .. versionadded:: 2014.1.0

    .. note::
        The ``runas`` argument is deprecated as of 2014.1.0. ``user`` should be
        used instead.

    CLI Example:

    .. code-block:: console

        salt '*' virtualenv.create /path/to/new/virtualenv

     Example of using --always-copy environment variable (in case your fs doesn't support symlinks).
     This will copy files into the virtualenv instead of symlinking them.

     .. code-block:: yaml

         - env:
           - VIRTUALENV_ALWAYS_COPY: 1
    '''
    if venv_bin is None:
        venv_bin = __opts__.get('venv_bin') or __pillar__.get('venv_bin')

    cmd = [venv_bin]

    if 'pyvenv' not in venv_bin:
        # ----- Stop the user if pyvenv only options are used --------------->
        # If any of the following values are not None, it means that the user
        # is actually passing a True or False value. Stop Him!
        if upgrade is not None:
            raise CommandExecutionError(
                'The `upgrade`(`--upgrade`) option is not supported '
                'by \'{0}\''.format(venv_bin)
            )
        elif symlinks is not None:
            raise CommandExecutionError(
                'The `symlinks`(`--symlinks`) option is not supported '
                'by \'{0}\''.format(venv_bin)
            )
        # <---- Stop the user if pyvenv only options are used ----------------

        virtualenv_version_info = virtualenv_ver(venv_bin, user=user, **kwargs)

        if distribute:
            if virtualenv_version_info >= (1, 10):
                log.info(
                    'The virtualenv \'--distribute\' option has been '
                    'deprecated in virtualenv(>=1.10), as such, the '
                    '\'distribute\' option to `virtualenv.create()` has '
                    'also been deprecated and it\'s not necessary anymore.'
                )
            else:
                cmd.append('--distribute')

        if python is not None and python.strip() != '':
            if not salt.utils.path.which(python):
                raise CommandExecutionError(
                    'Cannot find requested python ({0}).'.format(python)
                )
            cmd.append('--python={0}'.format(python))
        if extra_search_dir is not None:
            if isinstance(extra_search_dir, string_types) and \
                    extra_search_dir.strip() != '':
                extra_search_dir = [
                    e.strip() for e in extra_search_dir.split(',')
                ]
            for entry in extra_search_dir:
                cmd.append('--extra-search-dir={0}'.format(entry))
        if never_download is True:
            if (1, 10) <= virtualenv_version_info < (14, 0, 0):
                log.info(
                    '--never-download was deprecated in 1.10.0, but reimplemented in 14.0.0. '
                    'If this feature is needed, please install a supported virtualenv version.'
                )
            else:
                cmd.append('--never-download')
        if prompt is not None and prompt.strip() != '':
            cmd.append('--prompt=\'{0}\''.format(prompt))
    else:
        # venv module from the Python >= 3.3 standard library

        # ----- Stop the user if virtualenv only options are being used ----->
        # If any of the following values are not None, it means that the user
        # is actually passing a True or False value. Stop Him!
        if python is not None and python.strip() != '':
            raise CommandExecutionError(
                'The `python`(`--python`) option is not supported '
                'by \'{0}\''.format(venv_bin)
            )
        elif extra_search_dir is not None and extra_search_dir.strip() != '':
            raise CommandExecutionError(
                'The `extra_search_dir`(`--extra-search-dir`) option is not '
                'supported by \'{0}\''.format(venv_bin)
            )
        elif never_download is not None:
            raise CommandExecutionError(
                'The `never_download`(`--never-download`) option is not '
                'supported by \'{0}\''.format(venv_bin)
            )
        elif prompt is not None and prompt.strip() != '':
            raise CommandExecutionError(
                'The `prompt`(`--prompt`) option is not supported '
                'by \'{0}\''.format(venv_bin)
            )
        # <---- Stop the user if virtualenv only options are being used ------

        if upgrade is True:
            cmd.append('--upgrade')
        if symlinks is True:
            cmd.append('--symlinks')

    # Common options to virtualenv and pyvenv
    if clear is True:
        cmd.append('--clear')
    if system_site_packages is True:
        cmd.append('--system-site-packages')

    # Finally the virtualenv path
    cmd.append(path)

    # Let's create the virtualenv
    ret = __salt__['cmd.run_all'](cmd, runas=user, python_shell=False, **kwargs)
    if ret['retcode'] != 0:
        # Something went wrong. Let's bail out now!
        return ret

    # Check if distribute and pip are already installed
    if salt.utils.platform.is_windows():
        venv_python = os.path.join(path, 'Scripts', 'python.exe')
        venv_pip = os.path.join(path, 'Scripts', 'pip.exe')
        venv_setuptools = os.path.join(path, 'Scripts', 'easy_install.exe')
    else:
        venv_python = os.path.join(path, 'bin', 'python')
        venv_pip = os.path.join(path, 'bin', 'pip')
        venv_setuptools = os.path.join(path, 'bin', 'easy_install')

    # Install setuptools
    if (pip or distribute) and not os.path.exists(venv_setuptools):
        _install_script(
            'https://bitbucket.org/pypa/setuptools/raw/default/ez_setup.py',
            path, venv_python, user, saltenv=saltenv, use_vt=use_vt
        )

        # clear up the distribute archive which gets downloaded
        for fpath in glob.glob(os.path.join(path, 'distribute-*.tar.gz*')):
            os.unlink(fpath)

    if ret['retcode'] != 0:
        # Something went wrong. Let's bail out now!
        return ret

    # Install pip
    if pip and not os.path.exists(venv_pip):
        _ret = _install_script(
            'https://bootstrap.pypa.io/get-pip.py',
            path, venv_python, user, saltenv=saltenv, use_vt=use_vt
        )
        # Let's update the return dictionary with the details from the pip
        # installation
        ret.update(
            retcode=_ret['retcode'],
            stdout='{0}\n{1}'.format(ret['stdout'], _ret['stdout']).strip(),
            stderr='{0}\n{1}'.format(ret['stderr'], _ret['stderr']).strip(),
        )

    return ret


def get_site_packages(venv):
    '''
    Return the path to the site-packages directory of a virtualenv

    venv
        Path to the virtualenv.

    CLI Example:

    .. code-block:: bash

        salt '*' virtualenv.get_site_packages /path/to/my/venv
    '''
    bin_path = _verify_virtualenv(venv)

    ret = __salt__['cmd.exec_code_all'](
        bin_path,
        'from distutils import sysconfig; '
            'print(sysconfig.get_python_lib())'
    )

    if ret['retcode'] != 0:
        raise CommandExecutionError('{stdout}\n{stderr}'.format(**ret))

    return ret['stdout']


def get_distribution_path(venv, distribution):
    '''
    Return the path to a distribution installed inside a virtualenv

    .. versionadded:: 2016.3.0

    venv
        Path to the virtualenv.
    distribution
        Name of the distribution. Note, all non-alphanumeric characters
        will be converted to dashes.

    CLI Example:

    .. code-block:: bash

        salt '*' virtualenv.get_distribution_path /path/to/my/venv my_distribution
    '''
    _verify_safe_py_code(distribution)
    bin_path = _verify_virtualenv(venv)

    ret = __salt__['cmd.exec_code_all'](
        bin_path,
        'import pkg_resources; '
            "print(pkg_resources.get_distribution('{0}').location)".format(
                distribution
            )
    )

    if ret['retcode'] != 0:
        raise CommandExecutionError('{stdout}\n{stderr}'.format(**ret))

    return ret['stdout']


def get_resource_path(venv,
                      package=None,
                      resource=None):
    '''
    Return the path to a package resource installed inside a virtualenv

    .. versionadded:: 2015.5.0

    venv
        Path to the virtualenv

    package
        Name of the package in which the resource resides

        .. versionadded:: 2016.3.0

    resource
        Name of the resource of which the path is to be returned

        .. versionadded:: 2016.3.0

    CLI Example:

    .. code-block:: bash

        salt '*' virtualenv.get_resource_path /path/to/my/venv my_package my/resource.xml
    '''
    _verify_safe_py_code(package, resource)
    bin_path = _verify_virtualenv(venv)

    ret = __salt__['cmd.exec_code_all'](
        bin_path,
        'import pkg_resources; '
            "print(pkg_resources.resource_filename('{0}', '{1}'))".format(
                package,
                resource
        )
    )

    if ret['retcode'] != 0:
        raise CommandExecutionError('{stdout}\n{stderr}'.format(**ret))

    return ret['stdout']


def get_resource_content(venv,
                         package=None,
                         resource=None):
    '''
    Return the content of a package resource installed inside a virtualenv

    .. versionadded:: 2015.5.0

    venv
        Path to the virtualenv

    package
        Name of the package in which the resource resides

        .. versionadded:: 2016.3.0

    resource
        Name of the resource of which the content is to be returned

        .. versionadded:: 2016.3.0

    CLI Example:

    .. code-block:: bash

        salt '*' virtualenv.get_resource_content /path/to/my/venv my_package my/resource.xml
    '''
    _verify_safe_py_code(package, resource)
    bin_path = _verify_virtualenv(venv)

    ret = __salt__['cmd.exec_code_all'](
        bin_path,
        'import pkg_resources; '
            "print(pkg_resources.resource_string('{0}', '{1}'))".format(
                package,
                resource
            )
    )

    if ret['retcode'] != 0:
        raise CommandExecutionError('{stdout}\n{stderr}'.format(**ret))

    return ret['stdout']


def _install_script(source, cwd, python, user, saltenv='base', use_vt=False):
    if not salt.utils.platform.is_windows():
        tmppath = salt.utils.files.mkstemp(dir=cwd)
    else:
        tmppath = __salt__['cp.cache_file'](source, saltenv)

    if not salt.utils.platform.is_windows():
        fn_ = __salt__['cp.cache_file'](source, saltenv)
        shutil.copyfile(fn_, tmppath)
        os.chmod(tmppath, 0o500)
        os.chown(tmppath, __salt__['file.user_to_uid'](user), -1)
    try:
        return __salt__['cmd.run_all'](
            [python, tmppath],
            runas=user,
            cwd=cwd,
            env={'VIRTUAL_ENV': cwd},
            use_vt=use_vt,
            python_shell=False,
        )
    finally:
        os.remove(tmppath)


def _verify_safe_py_code(*args):
    for arg in args:
        if not salt.utils.verify.safe_py_code(arg):
            raise SaltInvocationError(
                'Unsafe python code detected in \'{0}\''.format(arg)
            )


def _verify_virtualenv(venv_path):
    bin_path = os.path.join(venv_path, 'bin/python')
    if not os.path.exists(bin_path):
        raise CommandExecutionError(
            'Path \'{0}\' does not appear to be a virtualenv: bin/python not found.'.format(venv_path)
        )
    return bin_path
