#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Copyright: (c) 2017, F5 Networks Inc.
# 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 = r'''
---
module: bigip_command
short_description: Run TMSH and BASH commands on F5 devices
description:
  - Sends a TMSH or BASH command to a BIG-IP node and returns the results
    read from the device. This module includes an argument that will cause
    the module to wait for a specific condition before returning or timing
    out if the condition is not met.
  - This module is B(not) idempotent, nor will it ever be. It is intended as
    a stop-gap measure to satisfy automation requirements until such a time as
    a real module has been developed to configure in the way you need.
  - If you are using this module, we recommend also filing an issue
    to have a B(real) module created for your needs.
version_added: "1.0.0"
options:
  commands:
    description:
      - The commands to send to the remote BIG-IP device over the
        configured provider. The resulting output from the command
        is returned. If the I(wait_for) argument is provided, the
        module is not returned until the condition is satisfied or
        the number of retries has expired.
      - Only C(tmsh) commands are supported. If you are piping or adding additional
        logic that is outside of C(tmsh) (such as grep'ing, awk'ing or other shell
        related logic that are not C(tmsh)), this behavior is not supported.
    required: True
    type: raw
  wait_for:
    description:
      - Specifies what to evaluate from the output of the command
        and what conditionals to apply.  This argument will cause
        the task to wait for a particular conditional to be true
        before moving forward. If the conditional is not true
        by the configured retries, the task fails. See the examples.
    type: list
    elements: str
    aliases: ['waitfor']
  match:
    description:
      - The I(match) argument is used in conjunction with the
        I(wait_for) argument to specify the match policy. Valid
        values are C(all) or C(any). If the value is set to C(all),
        then all conditionals in the I(wait_for) must be satisfied. If
        the value is set to C(any) then only one of the values must be
        satisfied.
    type: str
    choices:
      - any
      - all
    default: all
  retries:
    description:
      - Specifies the number of retries a command should be tried
        before it is considered failed. The command is run on the
        target device every retry and evaluated against the I(wait_for)
        conditionals.
    type: int
    default: 10
  interval:
    description:
      - Configures the interval in seconds to wait between retries
        of the command. If the command does not pass the specified
        conditional, the interval indicates how to long to wait before
        trying the command again.
    type: int
    default: 1
  warn:
    description:
      - Whether the module should raise warnings related to command idempotency
        or not.
      - Note that the F5 Ansible developers specifically leave this on to make you
        aware that your usage of this module may be better served by official F5
        Ansible modules. This module should always be used as a last resort.
    default: True
    type: bool
  chdir:
    description:
      - Change into this directory before running the command.
    type: str
notes:
  - When running this module in an HA environment via SSH connection and using a role other than C(admin)
    or C(root), you may see a C(Change Pending) status, even if you did not make any changes.
    This is being tracked with ID429869.
  - When using the bigip_command module with the REST API, there are a number of places regex is used
    internally to escape characters such as quotation marks. If your TMSH command contains regex characters itself,
    such as datagroup wildcards C(*), then a large amount of escape characters may be needed.
extends_documentation_fragment: f5networks.f5_modules.f5_rest_cli
author:
  - Tim Rupp (@caphrim007)
  - Wojciech Wypior (@wojtek0806)
'''

EXAMPLES = r'''
- name: run show version on remote devices
  bigip_command:
    commands: show sys version
    provider:
      server: lb.mydomain.com
      password: secret
      user: admin
  delegate_to: localhost

- name: run show version and check to see if output contains BIG-IP
  bigip_command:
    commands: show sys version
    wait_for: result[0] contains BIG-IP
    provider:
      server: lb.mydomain.com
      password: secret
      user: admin
  register: result
  delegate_to: localhost

- name: run multiple commands on remote nodes
  bigip_command:
    commands:
      - show sys version
      - list ltm virtual
    provider:
      server: lb.mydomain.com
      password: secret
      user: admin
  delegate_to: localhost

- name: run multiple commands and evaluate the output
  bigip_command:
    commands:
      - show sys version
      - list ltm virtual
    wait_for:
      - result[0] contains BIG-IP
      - result[1] contains my-vs
    provider:
      server: lb.mydomain.com
      password: secret
      user: admin
  register: result
  delegate_to: localhost

- name: tmsh prefixes will automatically be handled
  bigip_command:
    commands:
      - show sys version
      - tmsh list ltm virtual
    provider:
      server: lb.mydomain.com
      password: secret
      user: admin
  delegate_to: localhost

- name: Delete all LTM nodes in Partition1, assuming no dependencies exist
  bigip_command:
    commands:
      - delete ltm node all
    chdir: Partition1
    provider:
      server: lb.mydomain.com
      password: secret
      user: admin
  delegate_to: localhost

- name: Command that contains wildcard character to be passed to tmsh
  bigip_command:
    commands:
      - modify ltm data-group internal dg_string records add { "my test\\\\\\\*string"  { data "value" }}
    provider:
      server: lb.mydomain.com
      password: secret
      user: admin
  delegate_to: localhost
'''

RETURN = r'''
stdout:
  description: The set of responses from the commands.
  returned: always
  type: list
  sample: ['...', '...']
stdout_lines:
  description: The value of stdout split into a list.
  returned: always
  type: list
  sample: [['...', '...'], ['...'], ['...']]
failed_conditions:
  description: The list of conditionals that have failed.
  returned: failed
  type: list
  sample: ['...', '...']
warn:
  description: Whether or not to raise warnings about modification commands.
  returned: changed
  type: bool
  sample: True
'''

import copy
import re
import shlex
import time
from datetime import datetime

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.six import string_types

from ansible_collections.ansible.netcommon.plugins.module_utils.network.common.parsing import Conditional
from ansible_collections.ansible.netcommon.plugins.module_utils.network.common.utils import (
    ComplexList, to_list
)

from collections import deque

from ..module_utils.bigip import F5RestClient
from ..module_utils.common import (
    F5ModuleError, AnsibleF5Parameters, f5_argument_spec, is_cli
)
from ..module_utils.icontrol import tmos_version
from ..module_utils.teem import send_teem

try:
    from ..module_utils.common import run_commands
    HAS_CLI_TRANSPORT = True
except ImportError:
    HAS_CLI_TRANSPORT = False


class NoChangeReporter(object):
    stdout_re = [
        # A general error when a resource already exists
        re.compile(r"The requested.*already exists"),

        # Returned when creating a duplicate cli alias
        re.compile(r"Data Input Error: shared.*already exists"),
    ]

    def find_no_change(self, responses):
        """Searches the response for something that looks like a change

        This method borrows heavily from Ansible's ``_find_prompt`` method
        defined in the ``lib/ansible/plugins/connection/network_cli.py::Connection``
        class.

        Arguments:
            response (string): The output from the command.

        Returns:
            bool: True when change is detected. False otherwise.
        """
        for response in responses:
            for regex in self.stdout_re:
                if regex.search(response):
                    return True
        return False


class Parameters(AnsibleF5Parameters):
    returnables = ['stdout', 'stdout_lines', 'warnings', 'executed_commands']

    def to_return(self):
        result = {}
        try:
            for returnable in self.returnables:
                result[returnable] = getattr(self, returnable)
            result = self._filter_params(result)
            return result
        except Exception:
            return result

    @property
    def raw_commands(self):
        if self._values['commands'] is None:
            return []
        if isinstance(self._values['commands'], string_types):
            result = [self._values['commands']]
        else:
            result = self._values['commands']
        return result

    def cmd_has_pipe(self, cmd):
        lex = shlex.shlex(cmd, posix=True)
        lex.whitespace = '|'
        lex.whitespace_split = True
        return len(list(lex)) > 1

    def convert_commands(self, commands):
        result = []
        for command in commands:
            tmp = dict(
                command='',
                pipeline=''
            )

            command = command.replace("'", "\\'")
            pipeline = command.split('|', 1) if self.cmd_has_pipe(command) else [command]
            tmp['command'] = pipeline[0]
            try:
                tmp['pipeline'] = pipeline[1]
            except IndexError:
                pass
            result.append(tmp)
        return result

    def convert_commands_cli(self, commands):
        result = []
        for command in commands:
            tmp = dict(
                command='',
                pipeline=''
            )

            pipeline = command.split('|', 1) if self.cmd_has_pipe(command) else [command]
            tmp['command'] = pipeline[0]
            try:
                tmp['pipeline'] = pipeline[1]
            except IndexError:
                pass
            result.append(tmp)
        return result

    def merge_command_dict(self, command):
        if command['pipeline'] != '':
            escape_patterns = r'([$"])'
            command['pipeline'] = re.sub(escape_patterns, r'\\\1', command['pipeline'])
            command['command'] = '{0} | {1}'.format(command['command'], command['pipeline']).strip()

    def merge_command_dict_cli(self, command):
        if command['pipeline'] != '':
            command['command'] = '{0} | {1}'.format(command['command'], command['pipeline']).strip()

    @property
    def rest_commands(self):
        # ['list ltm virtual']
        commands = self.normalized_commands
        commands = self.convert_commands(commands)
        if self.chdir:
            # ['cd /Common; list ltm virtual']
            for command in commands:
                self.addon_chdir(command)
        # ['tmsh -c "cd /Common; list ltm virtual"']
        for command in commands:
            self.addon_tmsh(command)
        for command in commands:
            self.merge_command_dict(command)
        result = [x['command'] for x in commands]
        return result

    @property
    def cli_commands(self):
        # ['list ltm virtual']
        commands = self.normalized_commands
        commands = self.convert_commands_cli(commands)
        if self.chdir:
            # ['cd /Common; list ltm virtual']
            for command in commands:
                self.addon_chdir(command)
        if not self.is_tmsh:
            # ['tmsh -c "cd /Common; list ltm virtual"']
            for command in commands:
                self.addon_tmsh_cli(command)
        for command in commands:
            self.merge_command_dict_cli(command)
        result = [x['command'] for x in commands]
        return result

    @property
    def normalized_commands(self):
        if self._values['normalized_commands'] is None:
            return None
        return deque(self._values['normalized_commands'])

    @property
    def chdir(self):
        if self._values['chdir'] is None:
            return None
        if self._values['chdir'].startswith('/'):
            return self._values['chdir']
        return '/{0}'.format(self._values['chdir'])

    @property
    def user_commands(self):
        commands = self.raw_commands
        return map(self._ensure_tmsh_prefix, commands)

    @property
    def wait_for(self):
        return self._values['wait_for'] or list()

    def addon_tmsh(self, command):
        escape_patterns = r'([$"])'
        if command['command'].count('"') % 2 != 0:
            raise Exception('Double quotes are unbalanced')
        command['command'] = re.sub(escape_patterns, r'\\\\\\\1', command['command'])
        command['command'] = 'tmsh -c \\\"{0}\\\"'.format(command['command'])

    def addon_tmsh_cli(self, command):
        if command['command'].count('"') % 2 != 0:
            raise Exception('Double quotes are unbalanced')
        command['command'] = 'tmsh -c "{0}"'.format(command['command'])

    def addon_chdir(self, command):
        command['command'] = "cd {0}; {1}".format(self.chdir, command['command'])


class BaseManager(object):
    def __init__(self, *args, **kwargs):
        self.module = kwargs.get('module', None)
        self.client = F5RestClient(**self.module.params)
        self.want = Parameters(params=self.module.params)
        self.want.update({'module': self.module})
        self.changes = Parameters(module=self.module)
        self.valid_configs = [
            'list', 'show', 'modify cli preference pager disabled'
        ]
        self.changed_command_prefixes = ('modify', 'create', 'delete')
        self.warnings = list()

    def _to_lines(self, stdout):
        lines = list()
        for item in stdout:
            if isinstance(item, string_types):
                item = item.split('\n')
            lines.append(item)
        return lines

    def _announce_warnings(self, result):
        warnings = result.pop('warnings', [])
        for warning in warnings:
            self.module.warn(warning)

    def notify_non_idempotent_commands(self, commands):
        for index, item in enumerate(commands):
            if any(item.startswith(x) for x in self.valid_configs):
                return
            else:
                self.warnings.append(
                    'Using "write" commands is not idempotent. You should use '
                    'a module that is specifically made for that. If such a '
                    'module does not exist, then please file a bug. The command '
                    'in question is "{0}..."'.format(item[0:40])
                )

    @staticmethod
    def normalize_commands(raw_commands):
        if not raw_commands:
            return None
        result = []
        for command in raw_commands:
            command = command.strip()
            if command[0:5] == 'tmsh ':
                command = command[4:].strip()
            result.append(command)
        return result

    def parse_commands(self):
        results = []
        commands = self._transform_to_complex_commands(self.commands)

        for index, item in enumerate(commands):
            # This needs to be removed so that the ComplexList used in to_commands
            # will work correctly.
            output = item.pop('output', None)

            if output == 'one-line' and 'one-line' not in item['command']:
                item['command'] += ' one-line'
            elif output == 'text' and 'one-line' in item['command']:
                item['command'] = item['command'].replace('one-line', '')

            results.append(item)
        return results

    def execute(self):
        if self.want.normalized_commands:
            result = self.want.normalized_commands
        else:
            result = self.normalize_commands(self.want.raw_commands)
            self.want.update({'normalized_commands': result})
        if not result:
            return False
        self.notify_non_idempotent_commands(self.want.normalized_commands)

        commands = self.parse_commands()
        retries = self.want.retries
        conditionals = [Conditional(c) for c in self.want.wait_for]

        if self.module.check_mode:
            return

        while retries > 0:
            responses = self._execute(commands)
            self._check_known_errors(responses)
            for item in list(conditionals):
                if item(responses):
                    if self.want.match == 'any':
                        conditionals = list()
                        break
                    conditionals.remove(item)
            if not conditionals:
                break

            time.sleep(self.want.interval)
            retries -= 1
        else:
            failed_conditions = [item.raw for item in conditionals]
            errmsg = 'The following wait_for conditional statements have not been satisfied.'
            raise F5ModuleError(errmsg, failed_conditions)
        stdout_lines = self._to_lines(responses)
        changes = {
            'stdout': responses,
            'stdout_lines': stdout_lines,
            'executed_commands': self.commands
        }
        if self.want.warn:
            changes['warnings'] = self.warnings
        self.changes = Parameters(params=changes, module=self.module)
        return self.determine_change(responses)

    def determine_change(self, responses):
        changer = NoChangeReporter()
        if changer.find_no_change(responses):
            return False
        if any(x for x in self.want.normalized_commands if x.startswith(self.changed_command_prefixes)):
            return True
        return False

    def _check_known_errors(self, responses):
        # A regex to match the error IDs used in the F5 v2 logging framework.
        # pattern = r'^[0-9A-Fa-f]+:?\d+?:'

        for resp in responses:
            if 'usage: tmsh' in resp:
                raise F5ModuleError(
                    "tmsh command printed its 'help' message instead of running your command. "
                    "This usually indicates unbalanced quotes."
                )

    def _transform_to_complex_commands(self, commands):
        spec = dict(
            command=dict(key=True),
            output=dict(
                default='text',
                choices=['text', 'one-line']
            ),
        )
        transform = ComplexList(spec, self.module)
        result = transform(commands)
        return result


class V1Manager(BaseManager):
    """Supports CLI (SSH) communication with the remote device

    """
    def _execute(self, commands):
        if self.want.is_tmsh:
            command = dict(
                command="modify cli preference pager disabled"
            )
        else:
            command = dict(
                command="tmsh modify cli preference pager disabled"
            )
        self.execute_on_device(command)
        return self.execute_on_device(commands)

    @property
    def commands(self):
        return self.want.cli_commands

    def is_tmsh(self):
        try:
            self.execute_on_device('tmsh -v')
        except Exception as ex:
            if 'Syntax Error:' in str(ex):
                return True
            raise
        return False

    def exec_module(self):
        result = dict()

        changed = self.execute()

        result.update(**self.changes.to_return())
        result.update(dict(changed=changed))
        self._announce_warnings(result)
        return result

    def execute(self):
        self.want.update({'is_tmsh': self.is_tmsh()})
        return super(V1Manager, self).execute()

    def execute_on_device(self, commands):
        result = run_commands(self.module, commands)
        return result


class V2Manager(BaseManager):
    """Supports REST communication with the remote device

    """
    def _execute(self, commands):
        return self.execute_on_device(commands)

    @property
    def commands(self):
        return self.want.rest_commands

    def exec_module(self):
        start = datetime.now().isoformat()
        version = tmos_version(self.client)
        result = dict()

        changed = self.execute()

        result.update(**self.changes.to_return())
        result.update(dict(changed=changed))
        self._announce_warnings(result)
        send_teem(start, self.client, self.module, version)
        return result

    def execute_on_device(self, commands):
        responses = []
        uri = "https://{0}:{1}/mgmt/tm/util/bash".format(
            self.client.provider['server'],
            self.client.provider['server_port'],
        )
        for item in to_list(commands):
            try:
                args = dict(
                    command='run',
                    utilCmdArgs='-c "{0}"'.format(item['command'])
                )
                resp = self.client.api.post(uri, json=args)
                response = resp.json()
                if 'commandResult' in response:
                    output = u'{0}'.format(response['commandResult'])
                    responses.append(output.strip())
            except ValueError as ex:
                raise F5ModuleError(str(ex))

            if 'code' in response and response['code'] == 400:
                if 'message' in response:
                    raise F5ModuleError(response['message'])
                else:
                    raise F5ModuleError(resp.content)
        return responses


class ModuleManager(object):
    def __init__(self, *args, **kwargs):
        self.kwargs = kwargs
        self.module = kwargs.get('module', None)

    def exec_module(self):
        if is_cli(self.module) and HAS_CLI_TRANSPORT:
            manager = self.get_manager('v1')
        else:
            manager = self.get_manager('v2')
        result = manager.exec_module()
        return result

    def get_manager(self, type):
        if type == 'v1':
            return V1Manager(**self.kwargs)
        elif type == 'v2':
            return V2Manager(**self.kwargs)


class ArgumentSpec(object):
    def __init__(self):
        self.supports_check_mode = True
        argument_spec = dict(
            commands=dict(
                type='raw',
                required=True
            ),
            wait_for=dict(
                type='list',
                elements='str',
                aliases=['waitfor']
            ),
            match=dict(
                default='all',
                choices=['any', 'all']
            ),
            retries=dict(
                default=10,
                type='int'
            ),
            interval=dict(
                default=1,
                type='int'
            ),
            warn=dict(
                type='bool',
                default='yes'
            ),
            chdir=dict()
        )
        # required to add CLI to choices and ssh_keyfile as per documentation
        provider_update = dict(
            transport=dict(
                type='str',
                default='rest',
                choices=['cli', 'rest']
            ),
            ssh_keyfile=dict(
                type='path'
            ),

        )
        new_spec = copy.deepcopy(f5_argument_spec)
        self.argument_spec = {}
        self.argument_spec.update(new_spec)
        self.argument_spec['provider']['options'].update(provider_update)
        self.argument_spec.update(argument_spec)


def main():
    spec = ArgumentSpec()

    module = AnsibleModule(
        argument_spec=spec.argument_spec,
        supports_check_mode=spec.supports_check_mode
    )

    try:
        mm = ModuleManager(module=module)
        results = mm.exec_module()
        module.exit_json(**results)
    except F5ModuleError as ex:
        module.fail_json(msg=str(ex))


if __name__ == '__main__':
    main()