Mini Shell

"""
Module for managing PowerShell through PowerShellGet (PSGet)

:depends:
    - PowerShell 5.0
    - PSGet

Support for PowerShell
"""

import logging
import xml.etree.ElementTree

import salt.utils.platform
import salt.utils.versions
from salt.exceptions import CommandExecutionError

# Set up logging
log = logging.getLogger(__name__)

# Define the module's virtual name
__virtualname__ = "psget"


def __virtual__():
    """
    Set the system module of the kernel is Windows
    """
    # Verify Windows
    if not salt.utils.platform.is_windows():
        log.debug("Module PSGet: Only available on Windows systems")
        return False, "Module PSGet: Only available on Windows systems"

    # Verify PowerShell
    powershell_info = __salt__["cmd.shell_info"]("powershell")
    if not powershell_info["installed"]:
        log.debug("Module PSGet: Requires PowerShell")
        return False, "Module PSGet: Requires PowerShell"

    # Verify PowerShell 5.0 or greater
    if salt.utils.versions.compare(powershell_info["version"], "<", "5.0"):
        log.debug("Module PSGet: Requires PowerShell 5 or newer")
        return False, "Module PSGet: Requires PowerShell 5 or newer."

    return __virtualname__


def _ps_xml_to_dict(parent, dic=None):
    """
    Formats powershell Xml to a dict.
    Note: This _ps_xml_to_dict is not perfect with powershell Xml.
    """

    if dic is None:
        dic = {}

    for child in parent:
        if list(child):
            new_dic = _ps_xml_to_dict(child, {})
            if "Name" in new_dic:
                dic[new_dic["Name"]] = new_dic
            else:
                try:
                    dic[
                        [name for ps_type, name in child.items() if ps_type == "Type"][
                            0
                        ]
                    ] = new_dic
                except IndexError:
                    dic[child.text] = new_dic
        else:
            for xml_type, name in child.items():
                if xml_type == "Name":
                    dic[name] = child.text

    return dic


def _pshell(cmd, cwd=None, depth=2):
    """
    Execute the desired powershell command and ensure that it returns data
    in Xml format and load that into python
    """

    cmd = f'{cmd} | ConvertTo-Xml -Depth {depth} -As "stream"'
    log.debug("DSC: %s", cmd)

    results = __salt__["cmd.run_all"](
        cmd, shell="powershell", cwd=cwd, python_shell=True
    )

    if "pid" in results:
        del results["pid"]

    if "retcode" not in results or results["retcode"] != 0:
        # run_all logs an error to log.error, fail hard back to the user
        raise CommandExecutionError(f"Issue executing powershell {cmd}", info=results)

    try:
        ret = _ps_xml_to_dict(
            xml.etree.ElementTree.fromstring(results["stdout"].encode("utf-8"))
        )
    except xml.etree.ElementTree.ParseError:
        results["stdout"] = results["stdout"][:1000] + ". . ."
        raise CommandExecutionError("No XML results from powershell", info=results)

    return ret


def bootstrap():
    """
    Make sure that nuget-anycpu.exe is installed.
    This will download the official nuget-anycpu.exe from the internet.

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.bootstrap
    """
    cmd = (
        "Get-PackageProvider -Name NuGet -ForceBootstrap | Select Name, Version,"
        " ProviderPath"
    )
    ret = _pshell(cmd, depth=1)
    return ret


def avail_modules(desc=False):
    """
    List available modules in registered Powershell module repositories.

    :param desc: If ``True``, the verbose description will be returned.
    :type  desc: ``bool``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.avail_modules
        salt 'win01' psget.avail_modules desc=True
    """
    cmd = "Find-Module | Select Name, Description"
    modules = _pshell(cmd, depth=1)
    names = []
    if desc:
        names = {}
    for key in modules:
        module = modules[key]
        if desc:
            names[module["Name"]] = module["Description"]
            continue
        names.append(module["Name"])
    return names


def list_modules(desc=False):
    """
    List currently installed PSGet Modules on the system.

    :param desc: If ``True``, the verbose description will be returned.
    :type  desc: ``bool``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.list_modules
        salt 'win01' psget.list_modules desc=True
    """
    cmd = "Get-InstalledModule"
    modules = _pshell(cmd)
    names = []
    if desc:
        names = {}
    for key in modules:
        module = modules[key]
        if desc:
            names[module["Name"]] = module
            continue
        names.append(module["Name"])
    return names


def install(
    name, minimum_version=None, required_version=None, scope=None, repository=None
):
    """
    Install a Powershell module from powershell gallery on the system.

    :param name: Name of a Powershell module
    :type  name: ``str``

    :param minimum_version: The maximum version to install, e.g. 1.23.2
    :type  minimum_version: ``str``

    :param required_version: Install a specific version
    :type  required_version: ``str``

    :param scope: The scope to install the module to, e.g. CurrentUser, Computer
    :type  scope: ``str``

    :param repository: The friendly name of a private repository, e.g. MyREpo
    :type  repository: ``str``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.install PowerPlan
    """
    # Putting quotes around the parameter protects against command injection
    flags = [("Name", name)]

    if minimum_version is not None:
        flags.append(("MinimumVersion", minimum_version))
    if required_version is not None:
        flags.append(("RequiredVersion", required_version))
    if scope is not None:
        flags.append(("Scope", scope))
    if repository is not None:
        flags.append(("Repository", repository))
    params = ""
    for flag, value in flags:
        params += f"-{flag} {value} "
    cmd = f"Install-Module {params} -Force"
    _pshell(cmd)
    return name in list_modules()


def update(name, maximum_version=None, required_version=None):
    """
    Update a PowerShell module to a specific version, or the newest

    :param name: Name of a Powershell module
    :type  name: ``str``

    :param maximum_version: The maximum version to install, e.g. 1.23.2
    :type  maximum_version: ``str``

    :param required_version: Install a specific version
    :type  required_version: ``str``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.update PowerPlan
    """
    # Putting quotes around the parameter protects against command injection
    flags = [("Name", name)]

    if maximum_version is not None:
        flags.append(("MaximumVersion", maximum_version))
    if required_version is not None:
        flags.append(("RequiredVersion", required_version))

    params = ""
    for flag, value in flags:
        params += f"-{flag} {value} "
    cmd = f"Update-Module {params} -Force"
    _pshell(cmd)
    return name in list_modules()


def remove(name):
    """
    Remove a Powershell DSC module from the system.

    :param  name: Name of a Powershell DSC module
    :type   name: ``str``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.remove PowerPlan
    """
    # Putting quotes around the parameter protects against command injection
    cmd = f'Uninstall-Module "{name}"'
    no_ret = _pshell(cmd)
    return name not in list_modules()


def register_repository(name, location, installation_policy=None):
    """
    Register a PSGet repository on the local machine

    :param name: The name for the repository
    :type  name: ``str``

    :param location: The URI for the repository
    :type  location: ``str``

    :param installation_policy: The installation policy
        for packages, e.g. Trusted, Untrusted
    :type  installation_policy: ``str``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.register_repository MyRepo https://myrepo.mycompany.com/packages
    """
    # Putting quotes around the parameter protects against command injection
    flags = [("Name", name)]

    flags.append(("SourceLocation", location))
    if installation_policy is not None:
        flags.append(("InstallationPolicy", installation_policy))

    params = ""
    for flag, value in flags:
        params += f"-{flag} {value} "
    cmd = f"Register-PSRepository {params}"
    no_ret = _pshell(cmd)
    return name not in list_modules()


def get_repository(name):
    """
    Get the details of a local PSGet repository

    :param  name: Name of the repository
    :type   name: ``str``

    CLI Example:

    .. code-block:: bash

        salt 'win01' psget.get_repository MyRepo
    """
    # Putting quotes around the parameter protects against command injection
    cmd = f'Get-PSRepository "{name}"'
    no_ret = _pshell(cmd)
    return name not in list_modules()