"""内存缓存，支持 TTL 过期"""

import time
from typing import Any


class MemoryCache:
    def __init__(self):
        self._store: dict[str, tuple[Any, float]] = {}

    def get(self, key: str) -> Any | None:
        if key not in self._store:
            return None
        value, expire_at = self._store[key]
        if time.time() > expire_at:
            del self._store[key]
            return None
        return value

    def set(self, key: str, value: Any, ttl: int = 300):
        self._store[key] = (value, time.time() + ttl)

    def delete(self, key: str):
        self._store.pop(key, None)

    def clear(self):
        self._store.clear()

    def cleanup(self):
        now = time.time()
        expired = [k for k, (_, exp) in self._store.items() if now > exp]
        for k in expired:
            del self._store[k]


cache = MemoryCache()