"""Base service manager plugin.

Provides the shared start/stop/enable/disable logic that product-specific
service managers (imav, im360) inherit from.
"""

import asyncio
import logging

from defence360agent import utils
from defence360agent.contracts import messages, plugins

logger = logging.getLogger(__name__)


class BaseServiceManager(plugins.MessageSink):
    """Base service manager: start/stop services based on config changes.

    Subclasses populate ``_services`` (list of async check callables)
    and ``_units`` (dict of name → unitctl) in their ``__init__``.
    """

    def __init__(self):
        self._lock = asyncio.Lock()
        self._services = []
        self._units = {}

    async def _ensure_consistent_services_state(self):
        for service in self._services:
            await service()

    @plugins.expect(messages.MessageType.ConfigUpdate)
    async def on_config_update(
        self, message_ignored: messages.MessageType.ConfigUpdate
    ):
        async with self._lock:
            await self._ensure_consistent_services_state()

    @utils.log_error_and_ignore()
    async def _ensure_service_status(
        self, unitctl, service_name, should_be_running, reload=False
    ):
        is_running = await unitctl.is_active()
        if is_running is not should_be_running:
            if should_be_running:
                logger.info(
                    "%s is enabled in the config but it is not"
                    " running. Enabling it...",
                    service_name,
                )
                await unitctl.enable(now=True)
                logger.info("Enabled %s", service_name)
            else:
                logger.info(
                    "%s is not enabled in the config but it is"
                    " running. Disabling it...",
                    service_name,
                )
                await unitctl.disable(now=True)
                logger.info("Disabled %s", service_name)
        else:
            if is_running and reload:
                await unitctl.reload()
                logger.info(
                    "Reloading %s after config update...", service_name
                )