#!/usr/bin/python
# -*- coding: utf-8 -*-

# Copyright: (c) 2020, Tobias Birkefeld (@tcraxs) <t@craxs.de>
# 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: zabbix_discovery_rule
short_description: Create/delete/update Zabbix discovery rules
description:
   - Create discovery rule.
   - Delete existing discovery rule.
   - Update existing discovery rule with new options.
author:
    - "Tobias Birkefeld (@tcraxs)"
requirements:
    - "python >= 3.9"
options:
    state:
        description:
            - Create or delete discovery rules.
        type: str
        default: "present"
        choices: [ "present", "absent" ]
    name:
        description:
            - Name of the discovery rule.
        required: true
        type: str
    iprange:
        description:
            - One or several IP ranges to check separated by commas.
        type: list
        elements: str
    dchecks:
        description:
            - List of dictionaries of discovery check objects.
            - For more information, review discovery check object documentation at
              U(https://www.zabbix.com/documentation/current/manual/api/reference/dcheck/object)
        suboptions:
            type:
                description:
                    - Type of check.
                type: str
                choices: ["SSH",
                          "LDAP",
                          "SMTP",
                          "FTP",
                          "HTTP",
                          "POP",
                          "NNTP",
                          "IMAP",
                          "TCP",
                          "Zabbix",
                          "SNMPv1",
                          "SNMPv2",
                          "ICMP",
                          "SNMPv3",
                          "HTTPS",
                          "Telnet"]
            ports:
                description:
                    - One or several port ranges to check separated by commas. Used for all checks except for ICMP.
                type: str
            key:
                description:
                    - "The value of this property differs depending on the type of the check:"
                    - "- key to query for Zabbix agent checks"
                    - "- SNMP OID for SNMPv1, SNMPv2 and SNMPv3 checks"
                type: str
            snmp_community:
                description:
                    - SNMP community.
                    - Required for SNMPv1 and SNMPv2 agent checks.
                type: str
            snmpv3_authpassphrase:
                description:
                    - Authentication passphrase used for SNMPv3 agent checks with security level set to authNoPriv or authPriv.
                type: str
            snmpv3_authprotocol:
                description:
                    - Authentication protocol used for SNMPv3 agent checks with security level set to authNoPriv or authPriv.
                    - "Possible values:"
                    - MD5
                    - SHA
                type: str
                choices: ["MD5", "SHA"]
            snmpv3_contextname:
                description:
                    - SNMPv3 context name. Used only by SNMPv3 checks.
                type: str
            snmpv3_privpassphrase:
                description:
                    - Privacy passphrase used for SNMPv3 agent checks with security level set to authPriv.
                type: str
            snmpv3_privprotocol:
                description:
                    - Privacy protocol used for SNMPv3 agent checks with security level set to authPriv.
                    - "Possible values:"
                    - DES
                    - AES
                type: str
                choices: ["DES", "AES"]
            snmpv3_securitylevel:
                description:
                    - Security level used for SNMPv3 agent checks.
                    - "Possible values:"
                    - noAuthNoPriv
                    - authNoPriv
                    - authPriv
                type: str
                choices: ["noAuthNoPriv", "authNoPriv", "authPriv"]
            snmpv3_securityname:
                description:
                    - Security name used for SNMPv3 agent checks.
                type: str
            uniq:
                description:
                    - Whether to use this check as a device uniqueness criteria.
                    - Only a single unique check can be configured for a discovery rule.
                    - Used for Zabbix agent, SNMPv1, SNMPv2 and SNMPv3 agent checks.
                    - "Possible values:"
                    - "no - (default) do not use this check as a uniqueness criteria"
                    - "yes - use this check as a uniqueness criteria"
                type: bool
                default: no
            host_source:
                description:
                    - Source for host name.
                    - "Possible values:"
                    - "DNS (default)"
                    - "IP"
                    - "discovery - discovery value of this check"
                    - Options is available since Zabbix 4.4
                type: str
                default: "DNS"
                choices: ["DNS", "IP", "discovery"]
            name_source:
                description:
                    - Source for visible name.
                    - "Possible values:"
                    - "none - (default) not specified"
                    - "DNS"
                    - "IP"
                    - "discovery - discovery value of this check"
                    - Options is available since Zabbix 4.4
                type: str
                default: "None"
                choices: ["None", "DNS", "IP", "discovery"]
        type: list
        elements: dict
        aliases: [ "dcheck" ]
    delay:
        description:
            - Execution interval of the discovery rule.
            - Accepts seconds, time unit with suffix and user macro.
        type: str
        default: "1h"
    proxy:
        description:
            - Name of the proxy used for discovery.
        type: str
    status:
        description:
            - Whether the discovery rule is enabled.
            - "Possible values:"
            - enabled (default)
            - disabled
        type: str
        default: "enabled"
        choices: ["enabled", "disabled"]

extends_documentation_fragment:
    - community.zabbix.zabbix
"""

EXAMPLES = r"""
# If you want to use Username and Password to be authenticated by Zabbix Server
- name: Set credentials to access Zabbix Server API
  ansible.builtin.set_fact:
    ansible_user: Admin
    ansible_httpapi_pass: zabbix

# If you want to use API token to be authenticated by Zabbix Server
# https://www.zabbix.com/documentation/current/en/manual/web_interface/frontend_sections/administration/general#api-tokens
- name: Set API token
  ansible.builtin.set_fact:
    ansible_zabbix_auth_key: 8ec0d52432c15c91fcafe9888500cf9a607f44091ab554dbee860f6b44fac895

# Base create discovery rule example
- name: Create discovery rule with ICMP and zabbix agent checks
  # set task level variables as we change ansible_connection plugin here
  vars:
    ansible_network_os: community.zabbix.zabbix
    ansible_connection: httpapi
    ansible_httpapi_port: 443
    ansible_httpapi_use_ssl: true
    ansible_httpapi_validate_certs: false
    ansible_zabbix_url_path: "zabbixeu"  # If Zabbix WebUI runs on non-default (zabbix) path ,e.g. http://<FQDN>/zabbixeu
    ansible_host: zabbix-example-fqdn.org
  community.zabbix.zabbix_discovery_rule:
    name: ACME
    state: present
    iprange: 192.168.1.1-255
    dchecks:
        - type: ICMP
        - type: Zabbix
          key: "system.hostname"
          ports: 10050
          uniq: yes
          host_source: "discovery"

# Base update (add new dcheck) discovery rule example
- name: Create discovery rule with ICMP and zabbix agent checks
  # set task level variables as we change ansible_connection plugin here
  vars:
    ansible_network_os: community.zabbix.zabbix
    ansible_connection: httpapi
    ansible_httpapi_port: 443
    ansible_httpapi_use_ssl: true
    ansible_httpapi_validate_certs: false
    ansible_zabbix_url_path: "zabbixeu"  # If Zabbix WebUI runs on non-default (zabbix) path ,e.g. http://<FQDN>/zabbixeu
    ansible_host: zabbix-example-fqdn.org
  community.zabbix.zabbix_discovery_rule:
    name: ACME
    state: present
    iprange: 192.168.1.1-255
    dchecks:
        - type: SNMPv3
          snmp_community: CUSTOMER@snmp3-readonly
          ports: "161"
          key: iso.3.6.1.2.1.1.1.0
          snmpv3_contextname: "ContextName"
          snmpv3_securityname: "SecurityName"
          snmpv3_securitylevel: "authPriv"
          snmpv3_authprotocol: "SHA"
          snmpv3_authpassphrase: "SeCrEt"
          snmpv3_privprotocol: "AES"
          snmpv3_privpassphrase: "TopSecret"
          uniq: no
          host_source: "DNS"
          name_source: "None"

# Base delete discovery rule example
- name: Delete discovery rule
  # set task level variables as we change ansible_connection plugin here
  vars:
    ansible_network_os: community.zabbix.zabbix
    ansible_connection: httpapi
    ansible_httpapi_port: 443
    ansible_httpapi_use_ssl: true
    ansible_httpapi_validate_certs: false
    ansible_zabbix_url_path: "zabbixeu"  # If Zabbix WebUI runs on non-default (zabbix) path ,e.g. http://<FQDN>/zabbixeu
    ansible_host: zabbix-example-fqdn.org
  community.zabbix.zabbix_discovery_rule:
    name: ACME
    state: absent
"""

RETURN = r"""
state:
  description: Discovery rule state at the end of execution.
  returned: on success
  type: str
  sample: "present"
drule:
  description: Discovery rule name.
  returned: on success
  type: str
  sample: "ACME"
druleid:
    description: Discovery rule id.
    returned: on success
    type: str
    sample: "42"
msg:
    description: The result of the operation
    returned: always
    type: str
    sample: "Discovery rule created: ACME, ID: 42"
"""


from ansible.module_utils.basic import AnsibleModule

from ansible_collections.community.zabbix.plugins.module_utils.base import ZabbixBase
from ansible.module_utils.compat.version import LooseVersion

import ansible_collections.community.zabbix.plugins.module_utils.helpers as zabbix_utils


class Dchecks(ZabbixBase):
    """
    Restructures the user defined discovery checks to fit the Zabbix API requirements
    """

    def construct_the_data(self, _dchecks):
        """Construct the user defined discovery check to fit the Zabbix API
        requirements
        Args:
            _dchecks: discovery checks to construct
        Returns:
            dict: user defined discovery checks
        """
        if _dchecks is None:
            return None
        constructed_data = []
        for check in _dchecks:
            constructed_check = {
                "type": zabbix_utils.helper_to_numeric_value([
                    "SSH",
                    "LDAP",
                    "SMTP",
                    "FTP",
                    "HTTP",
                    "POP",
                    "NNTP",
                    "IMAP",
                    "TCP",
                    "Zabbix",
                    "SNMPv1",
                    "SNMPv2",
                    "ICMP",
                    "SNMPv3",
                    "HTTPS",
                    "Telnet"], check.get("type")
                ),
                "uniq": int(check.get("uniq"))
            }
            constructed_check.update({
                "host_source": zabbix_utils.helper_to_numeric_value([
                    "None",
                    "DNS",
                    "IP",
                    "discovery"], check.get("host_source")
                ),
                "name_source": zabbix_utils.helper_to_numeric_value([
                    "None",
                    "DNS",
                    "IP",
                    "discovery"], check.get("name_source")
                )
            })
            if constructed_check["type"] in (0, 1, 2, 3, 4, 5, 6, 7, 8, 14, 15):
                constructed_check["ports"] = check.get("ports")
            if constructed_check["type"] == 9:
                constructed_check["ports"] = check.get("ports")
                constructed_check["key_"] = check.get("key")
            if constructed_check["type"] in (10, 11):
                constructed_check["ports"] = check.get("ports")
                constructed_check["snmp_community"] = check.get("snmp_community")
                constructed_check["key_"] = check.get("key")
            if constructed_check["type"] == 13:
                constructed_check["ports"] = check.get("ports")
                constructed_check["key_"] = check.get("key")
                constructed_check["snmpv3_contextname"] = check.get("snmpv3_contextname")
                constructed_check["snmpv3_securityname"] = check.get("snmpv3_securityname")
                constructed_check["snmpv3_securitylevel"] = zabbix_utils.helper_to_numeric_value([
                    "noAuthNoPriv",
                    "authNoPriv",
                    "authPriv"], check.get("snmpv3_securitylevel")
                )
                if constructed_check["snmpv3_securitylevel"] in (1, 2):
                    constructed_check["snmpv3_authprotocol"] = zabbix_utils.helper_to_numeric_value([
                        "MD5",
                        "SHA"], check.get("snmpv3_authprotocol")
                    )
                    constructed_check["snmpv3_authpassphrase"] = check.get("snmpv3_authpassphrase")
                if constructed_check["snmpv3_securitylevel"] == 2:
                    constructed_check["snmpv3_privprotocol"] = zabbix_utils.helper_to_numeric_value([
                        "DES",
                        "AES"], check.get("snmpv3_privprotocol")
                    )
                    constructed_check["snmpv3_privpassphrase"] = check.get("snmpv3_privpassphrase")
            constructed_data.append(constructed_check)
        return zabbix_utils.helper_cleanup_data(constructed_data)


class DiscoveryRule(ZabbixBase):
    def check_if_drule_exists(self, name):
        """Check if discovery rule exists.
        Args:
            name: Name of the discovery rule.
        Returns:
            The return value. True for success, False otherwise.
        """
        try:
            _drule = self._zapi.drule.get({
                "output": "extend",
                "selectDChecks": "extend",
                "filter": {"name": [name]}
            })
            if len(_drule) > 0:
                return _drule
        except Exception as e:
            self._module.fail_json(msg="Failed to check if discovery rule '%s' exists: %s"
                                       % (name, e))

    def get_drule_by_drule_name(self, name):
        """Get discovery rule by discovery rule name
        Args:
            name: discovery rule name.
        Returns:
            discovery rule matching discovery rule name
        """
        try:
            drule_list = self._zapi.drule.get({
                "output": "extend",
                "selectDChecks": "extend",
                "filter": {"name": [name]}
            })
            if len(drule_list) < 1:
                self._module.fail_json(msg="Discovery rule not found: %s" % name)
            else:
                return drule_list[0]
        except Exception as e:
            self._module.fail_json(msg="Failed to get discovery rule '%s': %s" % (name, e))

    def get_proxy_by_proxy_name(self, proxy_name):
        """Get proxy by proxy name
        Args:
            proxy_name: proxy name.
        Returns:
            proxy matching proxy name
        """
        try:
            proxy_list = self._zapi.proxy.get({
                "output": "extend",
                "selectInterface": "extend",
                "filter": {"host": [proxy_name]}
            })
            if len(proxy_list) < 1:
                self._module.fail_json(msg="Proxy not found: %s" % proxy_name)
            else:
                return proxy_list[0]
        except Exception as e:
            self._module.fail_json(msg="Failed to get proxy '%s': %s" % (proxy_name, e))

    def _construct_parameters(self, **kwargs):
        """Construct parameters.
        Args:
            **kwargs: Arbitrary keyword parameters.
        Returns:
            dict: dictionary of specified parameters
        """
        _params = {
            "name": kwargs["name"],
            "iprange": ",".join(kwargs["iprange"]),
            "delay": kwargs["delay"],
            "status": zabbix_utils.helper_to_numeric_value([
                "enabled",
                "disabled"], kwargs["status"]
            ),
            "dchecks": kwargs["dchecks"]
        }
        if kwargs["proxy"]:
            _params["proxy_hostid"] = self.get_proxy_by_proxy_name(kwargs["proxy"])["proxyid"]
        return _params

    def check_difference(self, **kwargs):
        """Check difference between discovery rule and user specified parameters.
        Args:
            **kwargs: Arbitrary keyword parameters.
        Returns:
            dict: dictionary of differences
        """
        existing_drule = zabbix_utils.helper_convert_unicode_to_str(self.check_if_drule_exists(kwargs["name"])[0])
        parameters = zabbix_utils.helper_convert_unicode_to_str(self._construct_parameters(**kwargs))
        change_parameters = {}
        if LooseVersion(self._zbx_api_version) < LooseVersion("6.4"):
            if existing_drule["nextcheck"]:
                existing_drule.pop("nextcheck")
        _diff = zabbix_utils.helper_cleanup_data(zabbix_utils.helper_compare_dictionaries(parameters, existing_drule, change_parameters))
        return _diff

    def update_drule(self, **kwargs):
        """Update discovery rule.
        Args:
            **kwargs: Arbitrary keyword parameters.
        Returns:
            drule: updated discovery rule
        """
        try:
            if self._module.check_mode:
                self._module.exit_json(msg="Discovery rule would be updated if check mode was not specified: ID %s" % kwargs["drule_id"], changed=True)
            kwargs["druleid"] = kwargs.pop("drule_id")
            return self._zapi.drule.update(kwargs)
        except Exception as e:
            self._module.fail_json(msg="Failed to update discovery rule ID '%s': %s" % (kwargs["drule_id"], e))

    def add_drule(self, **kwargs):
        """Add discovery rule
        Args:
            **kwargs: Arbitrary keyword parameters
        Returns:
            drule: created discovery rule
        """
        try:
            if self._module.check_mode:
                self._module.exit_json(msg="Discovery rule would be added if check mode was not specified", changed=True)
            parameters = self._construct_parameters(**kwargs)
            drule_list = self._zapi.drule.create(parameters)
            return drule_list["druleids"][0]
        except Exception as e:
            self._module.fail_json(msg="Failed to create discovery rule %s: %s" % (kwargs["name"], e))

    def delete_drule(self, drule_id):
        """Delete discovery rule.
        Args:
            drule_id: Discovery rule id
        Returns:
            drule: deleted discovery rule
        """
        try:
            if self._module.check_mode:
                self._module.exit_json(changed=True, msg="Discovery rule would be deleted if check mode was not specified")
            return self._zapi.drule.delete([drule_id])
        except Exception as e:
            self._module.fail_json(msg="Failed to delete discovery rule '%s': %s" % (drule_id, e))


def main():
    argument_spec = zabbix_utils.zabbix_common_argument_spec()
    argument_spec.update(
        name=dict(type="str", required=True),
        iprange=dict(type="list", required=False, elements="str"),
        dchecks=dict(
            type="list",
            required=False,
            aliases=["dcheck"],
            elements="dict",
            options=dict(
                type=dict(type="str", choices=[
                    "SSH",
                    "LDAP",
                    "SMTP",
                    "FTP",
                    "HTTP",
                    "POP",
                    "NNTP",
                    "IMAP",
                    "TCP",
                    "Zabbix",
                    "SNMPv1",
                    "SNMPv2",
                    "ICMP",
                    "SNMPv3",
                    "HTTPS",
                    "Telnet"]
                ),
                ports=dict(type="str"),
                key=dict(type="str", no_log=False),
                snmp_community=dict(type="str"),
                snmpv3_authpassphrase=dict(type="str", no_log=True),
                snmpv3_authprotocol=dict(type="str", choices=["MD5", "SHA"]),
                snmpv3_contextname=dict(type="str"),
                snmpv3_privpassphrase=dict(type="str", no_log=True),
                snmpv3_privprotocol=dict(type="str", choices=["DES", "AES"]),
                snmpv3_securitylevel=dict(type="str", choices=["noAuthNoPriv", "authNoPriv", "authPriv"]),
                snmpv3_securityname=dict(type="str"),
                uniq=dict(type="bool", default=False),
                host_source=dict(type="str", choices=["DNS", "IP", "discovery"], default="DNS"),
                name_source=dict(type="str", choices=["None", "DNS", "IP", "discovery"], default="None")
            ),
            required_if=[
                ["type", "SSH", ["ports"]],
                ["type", "LDAP", ["ports"]],
                ["type", "SMTP", ["ports"]],
                ["type", "FTP", ["ports"]],
                ["type", "HTTP", ["ports"]],
                ["type", "POP", ["ports"]],
                ["type", "NNTP", ["ports"]],
                ["type", "IMAP", ["ports"]],
                ["type", "TCP", ["ports"]],
                ["type", "Zabbix", ["ports", "key"]],
                ["type", "SNMPv1", ["ports", "key", "snmp_community"]],
                ["type", "SNMPv2", ["ports", "key", "snmp_community"]],
                ["type", "SNMPv3", ["ports", "key"]],
                ["type", "HTTPS", ["ports"]],
                ["type", "Telnet", ["ports"]],
                ["snmpv3_securitylevel", "authPriv", ["snmpv3_privpassphrase"]]
            ]
        ),
        delay=dict(type="str", required=False, default="1h"),
        proxy=dict(type="str", required=False, default=None),
        status=dict(type="str", default="enabled", choices=["enabled", "disabled"]),
        state=dict(type="str", default="present", choices=["present", "absent"])
    )

    module = AnsibleModule(
        argument_spec=argument_spec,
        required_if=[
            ["state", "present", ["name", "iprange", "dchecks"]],
            ["state", "absent", ["name"]],
        ],
        supports_check_mode=True
    )

    state = module.params["state"]
    name = module.params["name"]
    iprange = module.params["iprange"]
    dchecks = module.params["dchecks"]
    delay = module.params["delay"]
    proxy = module.params["proxy"]
    status = module.params["status"]

    drule = DiscoveryRule(module)
    zbx = drule._zapi
    dcks = Dchecks(module, zbx)

    drule_exists = drule.check_if_drule_exists(name)

    if drule_exists:
        drule_id = drule.get_drule_by_drule_name(name)["druleid"]
        if state == "absent":
            drule.delete_drule(drule_id)
            module.exit_json(changed=True, state=state, drule=name, druleid=drule_id, msg="Discovery Rule deleted: %s, ID: %s" % (name, drule_id))
        else:
            difference = drule.check_difference(
                drule_id=drule_id,
                name=name,
                iprange=iprange,
                dchecks=dcks.construct_the_data(dchecks),
                delay=delay,
                proxy=proxy,
                status=status
            )

            if difference == {}:
                module.exit_json(changed=False, state=state, drule=name, druleid=drule_id, msg="Discovery Rule is up to date: %s" % name)
            else:
                drule_id = drule.update_drule(
                    drule_id=drule_id,
                    **difference
                )
                module.exit_json(changed=True, state=state, drule=name, druleid=drule_id, msg="Discovery Rule updated: %s, ID: %s" % (name, drule_id))
    else:
        if state == "absent":
            module.exit_json(changed=False, state=state, drule=name, msg="Discovery rule %s does not exist, nothing to delete" % name)
        else:
            drule_id = drule.add_drule(
                name=name,
                iprange=iprange,
                dchecks=dcks.construct_the_data(dchecks),
                delay=delay,
                proxy=proxy,
                status=status
            )
            module.exit_json(changed=True, state=state, drule=name, druleid=drule_id, msg="Discovery Rule created: %s, ID: %s" % (name, drule_id))


if __name__ == "__main__":
    main()
