from dataclasses import dataclass, field
from datetime import datetime, time, timedelta

from yuxi.utils.datetime_utils import utc_now_naive


@dataclass
class TimeWindow:
    start: time
    end: time


@dataclass
class ScheduleConfig:
    workdays: list[int] = field(default_factory=lambda: [0, 1, 2, 3, 4])
    work_hours: TimeWindow = field(default_factory=lambda: TimeWindow(time(9, 0), time(18, 0)))
    off_hours_reply: str | None = None
    timezone_offset_hours: int = 8


class SchedulePolicy:
    DEFAULT_OFF_HOURS_REPLY = "\u5f53\u524d\u4e3a\u975e\u5de5\u4f5c\u65f6\u95f4\uff0c\u6211\u5c06\u5728\u5de5\u4f5c\u65f6\u95f4\u5c3d\u5feb\u56de\u590d\u4f60\u3002"  # noqa: E501

    def __init__(self):
        self._config = ScheduleConfig()

    def configure(self, config: ScheduleConfig) -> None:
        self._config = config

    def is_working_hours(self, now: datetime | None = None) -> bool:
        dt = now or utc_now_naive()
        offset_delta = timedelta(hours=self._config.timezone_offset_hours)
        local_dt = dt + offset_delta
        weekday = local_dt.weekday()
        if weekday not in self._config.workdays:
            return False
        current_time = local_dt.time()
        window = self._config.work_hours
        if window.start <= window.end:
            return window.start <= current_time <= window.end
        return current_time >= window.start or current_time <= window.end

    def get_off_hours_reply(self, now: datetime | None = None) -> str | None:
        if not self.is_working_hours(now=now):
            return self._config.off_hours_reply or self.DEFAULT_OFF_HOURS_REPLY
        return None