#!/usr/bin/python
# Copyright: 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


ANSIBLE_METADATA = {'metadata_version': '1.1',
                    'status': ['preview'],
                    'supported_by': 'network'}


DOCUMENTATION = """
---
module: nxos_command
extends_documentation_fragment: nxos
version_added: "2.1"
author: "Peter Sprygada (@privateip)"
short_description: Run arbitrary command on Cisco NXOS devices
description:
  - Sends an arbitrary command to an NXOS 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.
options:
  commands:
    description:
      - The commands to send to the remote NXOS device.  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 retires as expired.
      - The I(commands) argument also accepts an alternative form
        that allows for complex values that specify the command
        to run and the output format to return.   This can be done
        on a command by command basis.  The complex argument supports
        the keywords C(command) and C(output) where C(command) is the
        command to run and C(output) is one of 'text' or 'json'.
    required: true
  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 examples.
    aliases: ['waitfor']
    version_added: "2.2"
  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.
    default: all
    version_added: "2.2"
  retries:
    description:
      - Specifies the number of retries a command should by tried
        before it is considered failed.  The command is run on the
        target device every retry and evaluated against the I(wait_for)
        conditionals.
    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.
    default: 1
"""

EXAMPLES = """
---
- name: run show version on remote devices
  nxos_command:
    commands: show version

- name: run show version and check to see if output contains Cisco
  nxos_command:
    commands: show version
    wait_for: result[0] contains Cisco

- name: run multiple commands on remote nodes
  nxos_command:
    commands:
      - show version
      - show interfaces

- name: run multiple commands and evaluate the output
  nxos_command:
    commands:
      - show version
      - show interfaces
    wait_for:
      - result[0] contains Cisco
      - result[1] contains loopback0

- name: run commands and specify the output format
  nxos_command:
    commands:
      - command: show version
        output: json
"""

RETURN = """
stdout:
  description: The set of responses from the commands
  returned: always apart from low level errors (such as action plugin)
  type: list
  sample: ['...', '...']
stdout_lines:
  description: The value of stdout split into a list
  returned: always apart from low level errors (such as action plugin)
  type: list
  sample: [['...', '...'], ['...'], ['...']]
failed_conditions:
  description: The list of conditionals that have failed
  returned: failed
  type: list
  sample: ['...', '...']
"""
import time

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.network.common.parsing import Conditional, FailedConditionalError
from ansible.module_utils.network.common.utils import ComplexList
from ansible.module_utils.network.nxos.nxos import check_args, nxos_argument_spec, run_commands
from ansible.module_utils.six import string_types
from ansible.module_utils._text import to_native


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


def parse_commands(module, warnings):
    transform = ComplexList(dict(
        command=dict(key=True),
        output=dict(),
        prompt=dict(),
        answer=dict()
    ), module)

    commands = transform(module.params['commands'])

    if module.check_mode:
        for item in list(commands):
            if not item['command'].startswith('show'):
                warnings.append(
                    'Only show commands are supported when using check_mode, not '
                    'executing %s' % item['command']
                )
                commands.remove(item)

    return commands


def to_cli(obj):
    cmd = obj['command']
    if obj.get('output') == 'json':
        cmd += ' | json'
    return cmd


def main():
    """entry point for module execution
    """
    argument_spec = dict(
        # { command: <str>, output: <str>, prompt: <str>, response: <str> }
        commands=dict(type='list', required=True),

        wait_for=dict(type='list', aliases=['waitfor']),
        match=dict(default='all', choices=['any', 'all']),

        retries=dict(default=10, type='int'),
        interval=dict(default=1, type='int')
    )

    argument_spec.update(nxos_argument_spec)

    module = AnsibleModule(argument_spec=argument_spec,
                           supports_check_mode=True)

    result = {'changed': False}

    warnings = list()
    check_args(module, warnings)
    commands = parse_commands(module, warnings)
    result['warnings'] = warnings

    wait_for = module.params['wait_for'] or list()

    try:
        conditionals = [Conditional(c) for c in wait_for]
    except AttributeError as exc:
        module.fail_json(msg=to_native(exc))

    retries = module.params['retries']
    interval = module.params['interval']
    match = module.params['match']

    while retries > 0:
        responses = run_commands(module, commands)

        for item in list(conditionals):
            try:
                if item(responses):
                    if match == 'any':
                        conditionals = list()
                        break
                    conditionals.remove(item)
            except FailedConditionalError as exc:
                module.fail_json(msg=to_native(exc))

        if not conditionals:
            break

        time.sleep(interval)
        retries -= 1

    if conditionals:
        failed_conditions = [item.raw for item in conditionals]
        msg = 'One or more conditional statements have not been satisfied'
        module.fail_json(msg=msg, failed_conditions=failed_conditions)

    result.update({
        'stdout': responses,
        'stdout_lines': to_lines(responses)
    })

    module.exit_json(**result)


if __name__ == '__main__':
    main()