#!/usr/bin/python

# Copyright (c) 2014, Anders Ingemann <aim@secoya.dk>
# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
# SPDX-License-Identifier: GPL-3.0-or-later

from __future__ import annotations

DOCUMENTATION = r"""
module: sensu_subscription
short_description: Manage Sensu subscriptions
description:
  - Manage which I(sensu channels) a machine should subscribe to.
deprecated:
  removed_in: 13.0.0
  why: Sensu Core and Sensu Enterprise products have been End of Life since 2019/20.
  alternative: Use Sensu Go and its accompanying collection C(sensu.sensu_go).
extends_documentation_fragment:
  - community.general.attributes
attributes:
  check_mode:
    support: full
  diff_mode:
    support: none
options:
  name:
    type: str
    description:
      - The name of the channel.
    required: true
  state:
    type: str
    description:
      - Whether the machine should subscribe or unsubscribe from the channel.
    choices: ['present', 'absent']
    default: present
  path:
    type: str
    description:
      - Path to the subscriptions JSON file.
    default: /etc/sensu/conf.d/subscriptions.json
  backup:
    description:
      - Create a backup file (if yes), including the timestamp information so you can get the original file back if you somehow
        clobbered it incorrectly.
    type: bool
    default: false
requirements: []
author: Anders Ingemann (@andsens)
"""

RETURN = r"""
reasons:
  description: The reasons why the module changed or did not change something.
  returned: success
  type: list
  sample: ["channel subscription was absent and state is 'present'"]
"""

EXAMPLES = r"""
# Subscribe to the nginx channel
- name: Subscribe to nginx checks
  community.general.sensu_subscription: name=nginx

# Unsubscribe from the common checks channel
- name: Unsubscribe from common checks
  community.general.sensu_subscription: name=common state=absent
"""

import json
import traceback

from ansible.module_utils.basic import AnsibleModule


def sensu_subscription(module, path, name, state="present", backup=False):
    changed = False
    reasons = []

    try:
        config = json.load(open(path))
    except OSError as e:
        if e.errno == 2:  # File not found, non-fatal
            if state == "absent":
                reasons.append("file did not exist and state is 'absent'")
                return changed, reasons
            config = {}
        else:
            module.fail_json(msg=f"{e}", exception=traceback.format_exc())
    except ValueError:
        msg = f"{path} contains invalid JSON"
        module.fail_json(msg=msg)

    if "client" not in config:
        if state == "absent":
            reasons.append("'client' did not exist and state is 'absent'")
            return changed, reasons
        config["client"] = {}
        changed = True
        reasons.append("'client' did not exist")

    if "subscriptions" not in config["client"]:
        if state == "absent":
            reasons.append("'client.subscriptions' did not exist and state is 'absent'")
            return changed, reasons
        config["client"]["subscriptions"] = []
        changed = True
        reasons.append("'client.subscriptions' did not exist")

    if name not in config["client"]["subscriptions"]:
        if state == "absent":
            reasons.append("channel subscription was absent")
            return changed, reasons
        config["client"]["subscriptions"].append(name)
        changed = True
        reasons.append("channel subscription was absent and state is 'present'")
    else:
        if state == "absent":
            config["client"]["subscriptions"].remove(name)
            changed = True
            reasons.append("channel subscription was present and state is 'absent'")

    if changed and not module.check_mode:
        if backup:
            module.backup_local(path)
        try:
            open(path, "w").write(json.dumps(config, indent=2) + "\n")
        except OSError as e:
            module.fail_json(msg=f"Failed to write to file {path}: {e}", exception=traceback.format_exc())

    return changed, reasons


def main():
    arg_spec = {
        "name": {"type": "str", "required": True},
        "path": {"type": "str", "default": "/etc/sensu/conf.d/subscriptions.json"},
        "state": {"type": "str", "default": "present", "choices": ["present", "absent"]},
        "backup": {"type": "bool", "default": False},
    }

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

    path = module.params["path"]
    name = module.params["name"]
    state = module.params["state"]
    backup = module.params["backup"]

    changed, reasons = sensu_subscription(module, path, name, state, backup)

    module.exit_json(path=path, name=name, changed=changed, msg="OK", reasons=reasons)


if __name__ == "__main__":
    main()