#!/usr/bin/env python3
# Copyright 2026 Valentin Haudiquet
# See LICENSE file for licensing details.

"""Charm the application."""

import logging
import time

import ops
from charms.traefik_k8s.v2.ingress import (
    IngressPerAppReadyEvent,
    IngressPerAppRequirer,
    IngressPerAppRevokedEvent,
)

# A standalone module for workload-specific logic (no charming concerns):
import charmed_server

logger = logging.getLogger(__name__)


class CharmedServerCharm(ops.CharmBase):
    """Charm the application."""

    def __init__(self, framework: ops.Framework):
        super().__init__(framework)
        framework.observe(self.on.install, self._on_install)
        framework.observe(self.on.start, self._on_start)
        framework.observe(self.on.config_changed, self._on_config_changed)

        self.ingress = IngressPerAppRequirer(self, port=80)
        framework.observe(self.ingress.on.ready, self._on_ingress_ready)
        framework.observe(self.ingress.on.revoked, self._on_ingress_revoked)

    def _on_ingress_ready(self, event: IngressPerAppReadyEvent):
        logger.info("This app's ingress URL: %s", event.url)

    def _on_ingress_revoked(self, event: IngressPerAppRevokedEvent):
        logger.info("This app no longer has ingress")

    def _on_install(self, event: ops.InstallEvent):
        """Install the workload on the machine."""
        charmed_server.install()

    def _on_start(self, event: ops.StartEvent):
        """Handle start event."""
        self.unit.status = ops.MaintenanceStatus("starting workload")
        self.configure_and_run()
        version = charmed_server.get_version()
        if version is not None:
            self.unit.set_workload_version(version)
        self.unit.status = ops.ActiveStatus()

    def _on_config_changed(self, event: ops.ConfigChangedEvent) -> None:
        """Handle config-changed event."""
        self.configure_and_run()

    def configure_and_run(self) -> None:
        """Ensure that nginx is running with the correct config."""
        if not charmed_server.is_installed():
            return
        changed = charmed_server.ensure_config()
        if not charmed_server.is_running():
            charmed_server.start()
            self.wait_for_running()
        elif changed:
            logger.info("Config changed while nginx is running. Updating nginx config")
            charmed_server.reload_config()

    def wait_for_running(self) -> None:
        """Wait for nginx to be running."""
        for _ in range(3):
            if charmed_server.is_running():
                return
            time.sleep(1)
        raise RuntimeError("nginx was not running within the expected time")

    def _on_stop(self, event: ops.StopEvent) -> None:
        """Handle stop event."""
        charmed_server.stop()


if __name__ == "__main__":  # pragma: nocover
    ops.main(CharmedServerCharm)