#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# (C) 2019 Red Hat Inc.
# Copyright (C) 2019 Western Telematic Inc.
#
# GNU General Public License v3.0+
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
#
# Module to configure WTI network IPTables Parameters on WTI OOB and PDU devices.
# CPM remote_management
#
from __future__ import absolute_import, division, print_function
__metaclass__ = type

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

DOCUMENTATION = """
---
module: cpm_iptables_config
version_added: "2.10.0"
author:
    - "Western Telematic Inc. (@wtinetworkgear)"
short_description: Set network IPTables parameters in WTI OOB and PDU devices
description:
    - "Set network IPTables parameters in WTI OOB and PDU devices"
options:
    cpm_url:
        description:
            - This is the URL of the WTI device to send the module.
        type: str
        required: true
    cpm_username:
        description:
            - This is the Username of the WTI device to send the module.
        type: str
        required: true
    cpm_password:
        description:
            - This is the Password of the WTI device to send the module.
        type: str
        required: true
    use_https:
        description:
            - Designates to use an https connection or http connection.
        type: bool
        required: false
        default: true
    validate_certs:
        description:
            - If false, SSL certificates will not be validated. This should only be used
            - on personally controlled sites using self-signed certificates.
        type: bool
        required: false
        default: true
    use_proxy:
        description:
            - Flag to control if the lookup will observe HTTP proxy environment variables when present.
        type: bool
        required: false
        default: false
    protocol:
        description:
            - The protocol that the iptables entry should be applied. 0 = ipv4, 1 = ipv6.
        type: int
        required: false
        choices: [ 0, 1 ]
    index:
        description:
            - Index in which command should be inserted. If not defined entry will start at position one.
        type: list
        required: false
        elements: raw
    command:
        description:
            - Actual iptables command to send to the WTI device.
        type: list
        required: true
        elements: raw
    clear:
        description:
            - Removes all the iptables for the protocol being defined before setting the newly defined entry.
        type: int
        required: false
        choices: [ 0, 1 ]
notes:
  - Use C(groups/cpm) in C(module_defaults) to set common options used between CPM modules.
"""

EXAMPLES = """
# Set Network IPTables Parameters
- name: Set the an IPTables Parameter for a WTI device
  cpm_iptables_config:
    cpm_url: "nonexist.wti.com"
    cpm_username: "super"
    cpm_password: "super"
    use_https: true
    validate_certs: false
    command: "iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 443 -j ACCEPT"

# Sets multiple Network IPTables Parameters
- name: Set the IPTables Parameters a WTI device
  cpm_iptables_config:
    cpm_url: "nonexist.wti.com"
    cpm_username: "super"
    cpm_password: "super"
    use_https: true
    validate_certs: false
    index:
      - 1
      - 2
    command:
      - "iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 443 -j ACCEPT"
      - "iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT"
"""

RETURN = """
data:
  description: The output JSON returned from the commands sent
  returned: always
  type: complex
  contains:
    iptables:
      description: Current k/v pairs of interface info for the WTI device after module execution.
      returned: always
      type: dict
      sample: [{ "eth0": { "ietf-ipv4": { "clear": 1, "entries": [
              { "entry": "iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 443 -j ACCEPT", "index": "1" },
              {"entry": "iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT", "index": "2" }]}}}]
"""

import base64
import json

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils._text import to_text, to_bytes, to_native
from ansible.module_utils.six.moves.urllib.error import HTTPError, URLError
from ansible.module_utils.urls import open_url, ConnectionError, SSLValidationError


def assemble_json(cpmmodule, existing_interface):
    total_change = total_commands = total_indices = 0
    is_clear = is_changed = protocol = 0
    negotiation = None
    json_load = ""
    ietfstring = "ietf-ipv4"

    indices = []
    commands = []

    for x in range(0, 48):
        indices.insert(x, None)
        commands.insert(x, None)

    if (cpmmodule.params['clear'] is not None):
        is_clear = int(cpmmodule.params['clear'])

    if (cpmmodule.params['protocol'] is not None):
        protocol = int(cpmmodule.params['protocol'])
        if (protocol == 1):
            ietfstring = "ietf-ipv6"

    index = cpmmodule.params['index']
    if (index is not None):
        if isinstance(index, list):
            for x in index:
                indices.insert(total_indices, (int(to_native(x))) - 1)
                total_indices += 1

    command = cpmmodule.params['command']
    if (command is not None):
        if isinstance(command, list):
            for x in command:
                if (total_indices == 0):
                    commands.insert(total_commands, to_native(x))
                else:
                    commands.insert(indices[total_commands], to_native(x))
                total_commands += 1

    if (total_indices > 0):
        if (total_commands != total_indices):
            return None

    for x in range(0, 48):
        if (commands[x] is not None):
            if ((existing_interface["iptables"][0]["eth0"][ietfstring]["entries"][x]["entry"] != commands[x]) or (is_clear == 1)):
                if (is_changed > 0):
                    json_load = '%s,' % (json_load)
                json_load = '%s{"entry": "%s","index": "%d"}' % (json_load, commands[x], (x + 1))
                is_changed += 1

    if (is_changed > 0) or (is_clear > 0):
        json_load = '{"iptables": [{"eth0": { "%s": { "clear": %d, "entries": [ %s ]}}}]}' % (ietfstring, is_clear, json_load)

    return json_load


def run_module():
    # define the available arguments/parameters that a user can pass to
    # the module
    module_args = dict(
        cpm_url=dict(type='str', required=True),
        cpm_username=dict(type='str', required=True),
        cpm_password=dict(type='str', required=True, no_log=True),
        protocol=dict(type='int', required=False, default=0, choices=[0, 1]),
        index=dict(type='list', elements='raw', required=False, default=None),
        command=dict(type='list', elements='raw', required=True),
        clear=dict(type='int', required=False, default=None, choices=[0, 1]),
        use_https=dict(type='bool', default=True),
        validate_certs=dict(type='bool', default=True),
        use_proxy=dict(type='bool', default=False)
    )

    result = dict(
        changed=False,
        data=''
    )

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

    auth = to_text(base64.b64encode(to_bytes('{0}:{1}'.format(to_native(module.params['cpm_username']), to_native(module.params['cpm_password'])),
                   errors='surrogate_or_strict')))

    if module.params['use_https'] is True:
        transport = "https://"
    else:
        transport = "http://"

    fullurl = ("%s%s/api/v2/config/iptables" % (transport, to_native(module.params['cpm_url'])))
    method = 'GET'
    try:
        response = open_url(fullurl, data=None, method=method, validate_certs=module.params['validate_certs'], use_proxy=module.params['use_proxy'],
                            headers={'Content-Type': 'application/json', 'Authorization': "Basic %s" % auth})

    except HTTPError as e:
        fail_json = dict(msg='GET: Received HTTP error for {0} : {1}'.format(fullurl, to_native(e)), changed=False)
        module.fail_json(**fail_json)
    except URLError as e:
        fail_json = dict(msg='GET: Failed lookup url for {0} : {1}'.format(fullurl, to_native(e)), changed=False)
        module.fail_json(**fail_json)
    except SSLValidationError as e:
        fail_json = dict(msg='GET: Error validating the server''s certificate for {0} : {1}'.format(fullurl, to_native(e)), changed=False)
        module.fail_json(**fail_json)
    except ConnectionError as e:
        fail_json = dict(msg='GET: Error connecting to {0} : {1}'.format(fullurl, to_native(e)), changed=False)
        module.fail_json(**fail_json)

    result['data'] = json.loads(response.read())
    payload = assemble_json(module, result['data'])

    if module.check_mode:
        if (payload is not None) and (len(payload) > 0):
            result['changed'] = True
    else:
        if (payload is not None) and (len(payload) > 0):
            fullurl = ("%s%s/api/v2/config/iptables" % (transport, to_native(module.params['cpm_url'])))
            method = 'POST'

            try:
                response = open_url(fullurl, data=payload, method=method, validate_certs=module.params['validate_certs'], use_proxy=module.params['use_proxy'],
                                    headers={'Content-Type': 'application/json', 'Authorization': "Basic %s" % auth})

            except HTTPError as e:
                fail_json = dict(msg='POST: Received HTTP error for {0} : {1}'.format(fullurl, to_native(e)), changed=False)
                module.fail_json(**fail_json)
            except URLError as e:
                fail_json = dict(msg='POST: Failed lookup url for {0} : {1}'.format(fullurl, to_native(e)), changed=False)
                module.fail_json(**fail_json)
            except SSLValidationError as e:
                fail_json = dict(msg='POST: Error validating the server''s certificate for {0} : {1}'.format(fullurl, to_native(e)), changed=False)
                module.fail_json(**fail_json)
            except ConnectionError as e:
                fail_json = dict(msg='POST: Error connecting to {0} : {1}'.format(fullurl, to_native(e)), changed=False)
                module.fail_json(**fail_json)

            result['changed'] = True
            result['data'] = json.loads(response.read())

    module.exit_json(**result)


def main():
    run_module()


if __name__ == '__main__':
    main()