import time
import filter
import dater
import handler
from http.server import HTTPServer
import logger
import grabber

class Server:
    def __init__(self, host: str, port: int, cache_duration: int, ics_url: str):
        self._host = host
        self._port = port
        self._cache_duration = cache_duration
        self._ics_url = ics_url
        self._cached_calendar = None
        self._cached_time = -cache_duration

    def _cache_calendar(self) -> bool:
        if not self._cached_calendar or self._cached_time + self._cache_duration < time.time():
            calendar = grabber.grab_calendar(self._ics_url)
            if not calendar:
                return False

            dater.date_calendar(calendar)

            self._cached_calendar = calendar
            self._cached_time = time.time()
            logger.info("Successfully cached calendar")

        return True

    def _response_callback(self, td_group: str, sh_group: str) -> str | None:
        if not self._cache_calendar():
            return None

        filtered_calendar = filter.filter_calendar(self._cached_calendar, td_group, sh_group)

        return filtered_calendar.serialize()

    def serve(self) -> None:
        handler_class = handler.generate_class(self._response_callback)
        server = HTTPServer((self._host, self._port), handler_class)
        logger.info(f"Listening on {self._host}:{self._port}")
        server.serve_forever()