# Copyright (c) 2018 Ansible Project
# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)

from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

DOCUMENTATION = """
author: Ansible Core Team
connection: psrp
short_description: Run tasks over Microsoft PowerShell Remoting Protocol
description:
- Run commands or put/fetch on a target via PSRP (WinRM plugin)
- This is similar to the I(winrm) connection plugin which uses the same
  underlying transport but instead runs in a PowerShell interpreter.
version_added: "2.7"
requirements:
- pypsrp (Python library)
options:
  # transport options
  remote_addr:
    description:
    - The hostname or IP address of the remote host.
    default: inventory_hostname
    vars:
    - name: ansible_host
    - name: ansible_psrp_host
  remote_user:
    description:
    - The user to log in as.
    vars:
    - name: ansible_user
    - name: ansible_psrp_user
  port:
    description:
    - The port for PSRP to connect on the remote target.
    - Default is C(5986) if I(protocol) is not defined or is C(https),
      otherwise the port is C(5985).
    vars:
    - name: ansible_port
    - name: ansible_psrp_port
  protocol:
    description:
    - Set the protocol to use for the connection.
    - Default is C(https) if I(port) is not defined or I(port) is not C(5985).
    choices:
    - http
    - https
    vars:
    - name: ansible_psrp_protocol
  path:
    description:
    - The URI path to connect to.
    vars:
    - name: ansible_psrp_path
    default: 'wsman'
  auth:
    description:
    - The authentication protocol to use when authenticating the remote user.
    - The default, C(negotiate), will attempt to use C(Kerberos) if it is
      available and fall back to C(NTLM) if it isn't.
    vars:
    - name: ansible_psrp_auth
    choices:
    - basic
    - certificate
    - negotiate
    - kerberos
    - ntlm
    - credssp
    default: negotiate
  cert_validation:
    description:
    - Whether to validate the remote server's certificate or not.
    - Set to C(ignore) to not validate any certificates.
    - I(cert_trust_path) can be set to the path of a PEM certificate chain to
      use in the validation.
    choices:
    - validate
    - ignore
    default: validate
    vars:
    - name: ansible_psrp_cert_validation
  cert_trust_path:
    description:
    - The path to a PEM certificate chain to use when validating the server's
      certificate.
    - This value is ignored if I(cert_validation) is set to C(ignore).
    vars:
    - name: ansible_psrp_cert_trust_path
  connection_timeout:
    description:
    - The connection timeout for making the request to the remote host.
    - This is measured in seconds.
    vars:
    - name: ansible_psrp_connection_timeout
    default: 30
  message_encryption:
    description:
    - Controls the message encryption settings, this is different from TLS
      encryption when I(ansible_psrp_protocol) is C(https).
    - Only the auth protocols C(negotiate), C(kerberos), C(ntlm), and
      C(credssp) can do message encryption. The other authentication protocols
      only support encryption when C(protocol) is set to C(https).
    - C(auto) means means message encryption is only used when not using
      TLS/HTTPS.
    - C(always) is the same as C(auto) but message encryption is always used
      even when running over TLS/HTTPS.
    - C(never) disables any encryption checks that are in place when running
      over HTTP and disables any authentication encryption processes.
    vars:
    - name: ansible_psrp_message_encryption
    choices:
    - auto
    - always
    - never
    default: auto
  proxy:
    description:
    - Set the proxy URL to use when connecting to the remote host.
    vars:
    - name: ansible_psrp_proxy
  ignore_proxy:
    description:
    - Will disable any environment proxy settings and connect directly to the
      remote host.
    - This option is ignored if C(proxy) is set.
    vars:
    - name: ansible_psrp_ignore_proxy
    type: bool
    default: 'no'

  # protocol options
  operation_timeout:
    description:
    - Sets the WSMan timeout for each operation.
    - This is measured in seconds.
    - This should not exceed the value for C(connection_timeout).
    vars:
    - name: ansible_psrp_operation_timeout
    default: 20
  max_envelope_size:
    description:
    - Sets the maximum size of each WSMan message sent to the remote host.
    - This is measured in bytes.
    - Defaults to C(150KiB) for compatibility with older hosts.
    vars:
    - name: ansible_psrp_max_envelope_size
    default: 153600
  configuration_name:
    description:
    - The name of the PowerShell configuration endpoint to connect to.
    vars:
    - name: ansible_psrp_configuration_name
    default: Microsoft.PowerShell
"""

import base64
import json
import os

from ansible.errors import AnsibleConnectionFailure, AnsibleError
from ansible.errors import AnsibleFileNotFound
from ansible.module_utils.parsing.convert_bool import boolean
from ansible.module_utils._text import to_bytes, to_native, to_text
from ansible.plugins.connection import ConnectionBase
from ansible.plugins.shell.powershell import _common_args
from ansible.utils.hashing import secure_hash
from ansible.utils.path import makedirs_safe

HAS_PYPSRP = True
PYPSRP_IMP_ERR = None
try:
    from pypsrp.complex_objects import GenericComplexObject, RunspacePoolState
    from pypsrp.exceptions import AuthenticationError, WinRMError
    from pypsrp.host import PSHost, PSHostUserInterface
    from pypsrp.powershell import PowerShell, RunspacePool
    from pypsrp.shell import Process, SignalCode, WinRS
    from pypsrp.wsman import WSMan, AUTH_KWARGS
except ImportError as err:
    HAS_PYPSRP = False
    PYPSRP_IMP_ERR = err

try:
    from __main__ import display
except ImportError:
    from ansible.utils.display import Display
    display = Display()


class Connection(ConnectionBase):

    transport = 'psrp'
    module_implementation_preferences = ('.ps1', '.exe', '')
    become_methods = ['runas']
    allow_executable = False
    has_pipelining = True
    allow_extras = True

    def __init__(self, *args, **kwargs):
        self.always_pipeline_modules = True
        self.has_native_async = True

        self.runspace = None
        self.host = None

        self._shell_type = 'powershell'
        super(Connection, self).__init__(*args, **kwargs)

    def _connect(self):
        if not HAS_PYPSRP:
            raise AnsibleError("pypsrp or dependencies are not installed: %s"
                               % to_native(PYPSRP_IMP_ERR))
        super(Connection, self)._connect()
        self._build_kwargs()
        display.vvv("ESTABLISH PSRP CONNECTION FOR USER: %s ON PORT %s TO %s" %
                    (self._psrp_user, self._psrp_port, self._psrp_host),
                    host=self._psrp_host)

        if not self.runspace:
            connection = WSMan(**self._psrp_conn_kwargs)

            # create our psuedo host to capture the exit code and host output
            host_ui = PSHostUserInterface()
            self.host = PSHost(None, None, False, "Ansible PSRP Host", None,
                               host_ui, None)

            self.runspace = RunspacePool(
                connection, host=self.host,
                configuration_name=self._psrp_configuration_name
            )
            display.vvvvv(
                "PSRP OPEN RUNSPACE: auth=%s configuration=%s endpoint=%s" %
                (self._psrp_auth, self._psrp_configuration_name,
                 connection.transport.endpoint), host=self._psrp_host
            )
            try:
                self.runspace.open()
            except AuthenticationError as e:
                raise AnsibleConnectionFailure("failed to authenticate with "
                                               "the server: %s" % to_native(e))
            except WinRMError as e:
                raise AnsibleConnectionFailure(
                    "psrp connection failure during runspace open: %s"
                    % to_native(e)
                )
            self._connected = True
        return self

    def reset(self):
        display.vvvvv("PSRP: Reset Connection", host=self._psrp_host)
        self.runspace = None
        self._connect()

    def exec_command(self, cmd, in_data=None, sudoable=True):
        super(Connection, self).exec_command(cmd, in_data=in_data,
                                             sudoable=sudoable)

        if cmd == "-" and not in_data.startswith(b"#!"):
            # The powershell plugin sets cmd to '-' when we are executing a
            # PowerShell script with in_data being the script to execute.
            script = in_data
            in_data = None
            display.vvv("PSRP: EXEC (via pipeline wrapper)",
                        host=self._psrp_host)
        elif cmd == "-":
            # ANSIBALLZ wrapper, we need to get the interpreter and execute
            # that as the script - note this won't work as basic.py relies
            # on packages not available on Windows, once fixed we can enable
            # this path
            interpreter = to_native(in_data.splitlines()[0][2:])
            # script = "$input | &'%s' -" % interpreter
            # in_data = to_text(in_data)
            raise AnsibleError("cannot run the interpreter '%s' on the psrp "
                               "connection plugin" % interpreter)
        elif cmd.startswith(" ".join(_common_args) + " -EncodedCommand"):
            # This is a PowerShell script encoded by the shell plugin, we will
            # decode the script and execute it in the runspace instead of
            # starting a new interpreter to save on time
            b_command = base64.b64decode(cmd.split(" ")[-1])
            script = to_text(b_command, 'utf-16-le')
            display.vvv("PSRP: EXEC %s" % script, host=self._psrp_host)
        else:
            # in other cases we want to execute the cmd as the script
            script = cmd
            display.vvv("PSRP: EXEC %s" % script, host=self._psrp_host)

        rc, stdout, stderr = self._exec_psrp_script(script, in_data)
        return rc, stdout, stderr

    def put_file(self, in_path, out_path):
        super(Connection, self).put_file(in_path, out_path)
        display.vvv("PUT %s TO %s" % (in_path, out_path), host=self._psrp_host)

        out_path = self._shell._unquote(out_path)
        script = u'''begin {
    $ErrorActionPreference = "Stop"

    $path = '%s'
    $fd = [System.IO.File]::Create($path)
    $algo = [System.Security.Cryptography.SHA1CryptoServiceProvider]::Create()
    $bytes = @()
} process {
    $bytes = [System.Convert]::FromBase64String($input)
    $algo.TransformBlock($bytes, 0, $bytes.Length, $bytes, 0) > $null
    $fd.Write($bytes, 0, $bytes.Length)
} end {
    $fd.Close()
    $algo.TransformFinalBlock($bytes, 0, 0) > $null
    $hash = [System.BitConverter]::ToString($algo.Hash)
    $hash = $hash.Replace("-", "").ToLowerInvariant()

    Write-Output -InputObject "{`"sha1`":`"$hash`"}"
}''' % self._shell._escape(out_path)

        cmd_parts = self._shell._encode_script(script, as_list=True,
                                               strict_mode=False,
                                               preserve_rc=False)
        b_in_path = to_bytes(in_path, errors='surrogate_or_strict')
        if not os.path.exists(b_in_path):
            raise AnsibleFileNotFound('file or module does not exist: "%s"'
                                      % to_native(in_path))

        in_size = os.path.getsize(b_in_path)
        buffer_size = int(self.runspace.connection.max_payload_size / 4 * 3)

        # copying files is faster when using the raw WinRM shell and not PSRP
        # we will create a WinRS shell just for this process
        # TODO: speed this up as there is overhead creating a shell for this
        with WinRS(self.runspace.connection, codepage=65001) as shell:
            process = Process(shell, cmd_parts[0], cmd_parts[1:])
            process.begin_invoke()

            offset = 0
            with open(b_in_path, 'rb') as src_file:
                for data in iter((lambda: src_file.read(buffer_size)), b""):
                    offset += len(data)
                    display.vvvvv("PSRP PUT %s to %s (offset=%d, size=%d" %
                                  (in_path, out_path, offset, len(data)),
                                  host=self._psrp_host)
                    b64_data = base64.b64encode(data) + b"\r\n"
                    process.send(b64_data, end=(src_file.tell() == in_size))

                # the file was empty, return empty buffer
                if offset == 0:
                    process.send(b"", end=True)

            process.end_invoke()
            process.signal(SignalCode.CTRL_C)

        if process.rc != 0:
            raise AnsibleError(to_native(process.stderr))

        put_output = json.loads(process.stdout)
        remote_sha1 = put_output.get("sha1")

        if not remote_sha1:
            raise AnsibleError("Remote sha1 was not returned, stdout: '%s', "
                               "stderr: '%s'" % (to_native(process.stdout),
                                                 to_native(process.stderr)))

        local_sha1 = secure_hash(in_path)
        if not remote_sha1 == local_sha1:
            raise AnsibleError("Remote sha1 hash %s does not match local hash "
                               "%s" % (to_native(remote_sha1),
                                       to_native(local_sha1)))

    def fetch_file(self, in_path, out_path):
        super(Connection, self).fetch_file(in_path, out_path)
        display.vvv("FETCH %s TO %s" % (in_path, out_path),
                    host=self._psrp_host)

        in_path = self._shell._unquote(in_path)
        out_path = out_path.replace('\\', '/')

        # because we are dealing with base64 data we need to get the max size
        # of the bytes that the base64 size would equal
        max_b64_size = int(self.runspace.connection.max_payload_size -
                           (self.runspace.connection.max_payload_size / 4 * 3))
        buffer_size = max_b64_size - (max_b64_size % 1024)

        # setup the file stream with read only mode
        setup_script = '''$ErrorActionPreference = "Stop"
$path = "%s"

if (Test-Path -Path $path -PathType Leaf) {
    $fs = New-Object -TypeName System.IO.FileStream -ArgumentList @(
        $path,
        [System.IO.FileMode]::Open,
        [System.IO.FileAccess]::Read,
        [System.IO.FileShare]::Read
    )
    $buffer_size = %d
} elseif (Test-Path -Path $path -PathType Container) {
    Write-Output -InputObject "[DIR]"
} else {
    Write-Error -Message "$path does not exist"
    $host.SetShouldExit(1)
}''' % (self._shell._escape(in_path), buffer_size)

        # read the file stream at the offset and return the b64 string
        read_script = '''$ErrorActionPreference = "Stop"
$fs.Seek(%d, [System.IO.SeekOrigin]::Begin) > $null
$buffer = New-Object -TypeName byte[] -ArgumentList $buffer_size
$bytes_read = $fs.Read($buffer, 0, $buffer_size)

if ($bytes_read -gt 0) {
    $bytes = $buffer[0..($bytes_read - 1)]
    Write-Output -InputObject ([System.Convert]::ToBase64String($bytes))
}'''

        # need to run the setup script outside of the local scope so the
        # file stream stays active between fetch operations
        rc, stdout, stderr = self._exec_psrp_script(setup_script,
                                                    use_local_scope=False)
        if rc != 0:
            raise AnsibleError("failed to setup file stream for fetch '%s': %s"
                               % (out_path, to_native(stderr)))
        elif stdout.strip() == '[DIR]':
            # in_path was a dir so we need to create the dir locally
            makedirs_safe(out_path)
            return

        b_out_path = to_bytes(out_path, errors='surrogate_or_strict')
        makedirs_safe(os.path.dirname(b_out_path))
        offset = 0
        with open(b_out_path, 'wb') as out_file:
            while True:
                display.vvvvv("PSRP FETCH %s to %s (offset=%d" %
                              (in_path, out_path, offset), host=self._psrp_host)
                rc, stdout, stderr = \
                    self._exec_psrp_script(read_script % offset)
                if rc != 0:
                    raise AnsibleError("failed to transfer file to '%s': %s"
                                       % (out_path, to_native(stderr)))

                data = base64.b64decode(stdout.strip())
                out_file.write(data)
                if len(data) < buffer_size:
                    break

            rc, stdout, stderr = self._exec_psrp_script("$fs.Close()")
            if rc != 0:
                display.warning("failed to close remote file stream of file "
                                "'%s': %s" % (in_path, to_native(stderr)))

    def close(self):
        if self.runspace and self.runspace.state == RunspacePoolState.OPENED:
            display.vvvvv("PSRP CLOSE RUNSPACE: %s" % (self.runspace.id),
                          host=self._psrp_host)
            self.runspace.close()
        self.runspace = None
        self._connected = False

    def _build_kwargs(self):
        self._become_method = self._play_context.become_method
        self._become_user = self._play_context.become_user
        self._become_pass = self._play_context.become_pass

        self._psrp_host = self.get_option('remote_addr')
        self._psrp_user = self.get_option('remote_user')
        self._psrp_pass = self._play_context.password

        protocol = self.get_option('protocol')
        port = self.get_option('port')
        if protocol is None and port is None:
            protocol = 'https'
            port = 5986
        elif protocol is None:
            protocol = 'https' if int(port) != 5985 else 'http'
        elif port is None:
            port = 5986 if protocol == 'https' else 5985

        self._psrp_protocol = protocol
        self._psrp_port = int(port)

        self._psrp_path = self.get_option('path')
        self._psrp_auth = self.get_option('auth')
        # cert validation can either be a bool or a path to the cert
        cert_validation = self.get_option('cert_validation')
        cert_trust_path = self.get_option('cert_trust_path')
        if cert_validation == 'ignore':
            self._psrp_cert_validation = False
        elif cert_trust_path is not None:
            self._psrp_cert_validation = cert_trust_path
        else:
            self._psrp_cert_validation = True

        self._psrp_connection_timeout = int(self.get_option('connection_timeout'))
        self._psrp_message_encryption = self.get_option('message_encryption')
        self._psrp_proxy = self.get_option('proxy')
        self._psrp_ignore_proxy = boolean(self.get_option('ignore_proxy'))
        self._psrp_operation_timeout = int(self.get_option('operation_timeout'))
        self._psrp_max_envelope_size = int(self.get_option('max_envelope_size'))
        self._psrp_configuration_name = self.get_option('configuration_name')

        supported_args = []
        for auth_kwarg in AUTH_KWARGS.values():
            supported_args.extend(auth_kwarg)
        extra_args = set([v.replace('ansible_psrp_', '') for v in
                          self.get_option('_extras')])
        unsupported_args = extra_args.difference(supported_args)

        for arg in unsupported_args:
            display.warning("ansible_psrp_%s is unsupported by the current "
                            "psrp version installed" % arg)

        self._psrp_conn_kwargs = dict(
            server=self._psrp_host, port=self._psrp_port,
            username=self._psrp_user, password=self._psrp_pass,
            ssl=self._psrp_protocol == 'https', path=self._psrp_path,
            auth=self._psrp_auth, cert_validation=self._psrp_cert_validation,
            connection_timeout=self._psrp_connection_timeout,
            encryption=self._psrp_message_encryption, proxy=self._psrp_proxy,
            no_proxy=self._psrp_ignore_proxy,
            max_envelope_size=self._psrp_max_envelope_size,
            operation_timeout=self._psrp_operation_timeout,
        )
        # add in the extra args that were set
        for arg in extra_args.intersection(supported_args):
            option = self.get_option('_extras')['ansible_psrp_%s' % arg]
            self._psrp_conn_kwargs[arg] = option

    def _exec_psrp_script(self, script, input_data=None, use_local_scope=True):
        ps = PowerShell(self.runspace)
        ps.add_script(script, use_local_scope=use_local_scope)
        ps.invoke(input=input_data)

        rc, stdout, stderr = self._parse_pipeline_result(ps)
        return rc, stdout, stderr

    def _parse_pipeline_result(self, pipeline):
        """
        PSRP doesn't have the same concept as other protocols with its output.
        We need some extra logic to convert the pipeline streams and host
        output into the format that Ansible understands.

        :param pipeline: The finished PowerShell pipeline that invoked our
            commands
        :return: rc, stdout, stderr based on the pipeline output
        """
        # we try and get the rc from our host implementation, this is set if
        # exit or $host.SetShouldExit() is called in our pipeline, if not we
        # set to 0 if the pipeline had not errors and 1 if it did
        rc = self.host.rc or (1 if pipeline.had_errors else 0)

        # TODO: figure out a better way of merging this with the host output
        stdout_list = []
        for output in pipeline.output:
            # Not all pipeline outputs are a string or contain a __str__ value,
            # we will create our own output based on the properties of the
            # complex object if that is the case.
            if isinstance(output, GenericComplexObject) and output.to_string is None:
                obj_lines = output.property_sets
                for key, value in output.adapted_properties.items():
                    obj_lines.append(u"%s: %s" % (key, value))
                for key, value in output.extended_properties.items():
                    obj_lines.append(u"%s: %s" % (key, value))
                output_msg = u"\n".join(obj_lines)
            else:
                output_msg = to_text(output, nonstring='simplerepr')

            stdout_list.append(output_msg)

        stdout = u"\r\n".join(stdout_list)
        if len(self.host.ui.stdout) > 0:
            stdout += u"\r\n" + u"".join(self.host.ui.stdout)

        stderr_list = []
        for error in pipeline.streams.error:
            # the error record is not as fully fleshed out like we usually get
            # in PS, we will manually create it here
            error_msg = "%s : %s\r\n" \
                        "%s\r\n" \
                        "    + CategoryInfo          : %s\r\n" \
                        "    + FullyQualifiedErrorId : %s" \
                        % (error.command_name, str(error),
                           error.invocation_position_message, error.message,
                           error.fq_error)
            stacktrace = error.script_stacktrace
            if self._play_context.verbosity >= 3 and stacktrace is not None:
                error_msg += "\r\nStackTrace:\r\n%s" % stacktrace
            stderr_list.append(error_msg)

        stderr = "\r\n".join(stderr_list)
        if len(self.host.ui.stderr) > 0:
            stderr += "\r\n" + "".join(self.host.ui.stderr)

        display.vvvvv("PSRP RC: %d" % rc, host=self._psrp_host)
        display.vvvvv("PSRP STDOUT: %s" % stdout, host=self._psrp_host)
        display.vvvvv("PSRP STDERR: %s" % stderr, host=self._psrp_host)

        # reset the host back output back to defaults, needed if running
        # multiple pipelines on the same RunspacePool
        self.host.rc = 0
        self.host.ui.stdout = []
        self.host.ui.stderr = []

        return rc, to_bytes(stdout, encoding='utf-8'), to_bytes(stderr, encoding='utf-8')
