import datetime
from typing import Iterable, Optional

import redis

from .config import settings


class RedisStore:
    def __init__(self, url: str) -> None:
        self._r = redis.Redis.from_url(url, decode_responses=True)

    @staticmethod
    def _today_key(prefix: str) -> str:
        today = datetime.datetime.utcnow().strftime("%Y%m%d")
        return f"eip:{prefix}:{today}"

    def add_used_ip_today(self, ip: str) -> None:
        key = self._today_key("used")
        self._r.sadd(key, ip)
        # 设置 2 天过期，跨时区冗余
        self._r.expire(key, 86400)

    def is_ip_used_today(self, ip: str) -> bool:
        key = self._today_key("used")
        return bool(self._r.sismember(key, ip))

    def get_used_count_today(self) -> int:
        key = self._today_key("used")
        return int(self._r.scard(key))

    def set_current(self, ip: str, edge_id: Optional[str]) -> None:
        self._r.hset("eip:current", mapping={"ip": ip, "edge": edge_id or ""})

    def get_current(self) -> dict:
        data = self._r.hgetall("eip:current")
        return data or {}

    def cache_candidates(self, items: Iterable[str]) -> None:
        key = self._today_key("candidates")
        if items:
            self._r.delete(key)
            self._r.rpush(key, *list(items))
            self._r.expire(key, 86400)


store_singleton = RedisStore(settings.redis_url)