#!/usr/bin/env python3
"""
Redis缓存模块
用于缓存账户列表、邮件数据等，加速页面加载
"""

import json
import logging
import os
import uuid
from datetime import datetime
from typing import Any, Optional

import redis.asyncio as redis

logger = logging.getLogger(__name__)

REDIS_URL = 'redis://:redis_XMiXNa@127.0.0.1:6379/0'

# 缓存过期时间（秒）
TTL_ACCOUNTS = 300       # 账户列表 5分钟
TTL_MESSAGES = 180       # 邮件列表 3分钟
TTL_PAYMENT = 600        # 支付状态 10分钟
TTL_NOTIFICATIONS = 604800  # 通知 7天

NOTIFICATIONS_KEY = 'notifications:unread'


class RedisCache:
    """Redis缓存管理器"""

    def __init__(self):
        self._redis: Optional[redis.Redis] = None

    async def connect(self):
        try:
            self._redis = redis.from_url(REDIS_URL, decode_responses=True)
            await self._redis.ping()
            logger.info(f"Redis连接成功: {REDIS_URL}")
        except Exception as e:
            logger.warning(f"Redis连接失败，将跳过缓存: {e}")
            self._redis = None

    async def close(self):
        if self._redis:
            await self._redis.aclose()

    @property
    def available(self) -> bool:
        return self._redis is not None

    async def get(self, key: str) -> Optional[Any]:
        if not self._redis:
            return None
        try:
            val = await self._redis.get(key)
            return json.loads(val) if val else None
        except Exception as e:
            logger.debug(f"Redis get 失败 [{key}]: {e}")
            return None

    async def set(self, key: str, value: Any, ttl: int = 300):
        if not self._redis:
            return
        try:
            await self._redis.set(key, json.dumps(value, ensure_ascii=False), ex=ttl)
        except Exception as e:
            logger.debug(f"Redis set 失败 [{key}]: {e}")

    async def delete(self, key: str):
        if not self._redis:
            return
        try:
            await self._redis.delete(key)
        except Exception:
            pass

    async def delete_pattern(self, pattern: str):
        """删除匹配模式的所有key"""
        if not self._redis:
            return
        try:
            async for key in self._redis.scan_iter(match=pattern, count=100):
                await self._redis.delete(key)
        except Exception:
            pass

    # ---- 业务快捷方法 ----

    def accounts_key(self) -> str:
        return "cache:accounts"

    def messages_key(self, email: str, folder: str) -> str:
        return f"cache:messages:{email}:{folder}"

    def payment_key(self) -> str:
        return "cache:payment_status"

    async def invalidate_accounts(self):
        await self.delete(self.accounts_key())

    async def invalidate_messages(self, email: str):
        await self.delete_pattern(f"cache:messages:{email}:*")

    async def invalidate_payment(self):
        await self.delete(self.payment_key())


    # ---- 通知系统 ----

    async def add_notification(self, email: str, ntype: str, message: str):
        """添加一条通知（LPUSH + EXPIRE）"""
        if not self._redis:
            return
        try:
            notif = json.dumps({
                'id': str(uuid.uuid4()),
                'email': email,
                'type': ntype,
                'message': message,
                'created_at': datetime.now().strftime('%Y-%m-%d %H:%M:%S')
            }, ensure_ascii=False)
            await self._redis.lpush(NOTIFICATIONS_KEY, notif)
            await self._redis.expire(NOTIFICATIONS_KEY, TTL_NOTIFICATIONS)
        except Exception as e:
            logger.debug(f"添加通知失败: {e}")

    async def get_notifications(self) -> list:
        """获取所有未读通知"""
        if not self._redis:
            return []
        try:
            items = await self._redis.lrange(NOTIFICATIONS_KEY, 0, -1)
            return [json.loads(item) for item in items]
        except Exception as e:
            logger.debug(f"获取通知失败: {e}")
            return []

    async def dismiss_notification(self, notif_id: str):
        """移除指定 id 的通知"""
        if not self._redis:
            return
        try:
            items = await self._redis.lrange(NOTIFICATIONS_KEY, 0, -1)
            for item in items:
                data = json.loads(item)
                if data.get('id') == notif_id:
                    await self._redis.lrem(NOTIFICATIONS_KEY, 1, item)
                    break
        except Exception as e:
            logger.debug(f"移除通知失败: {e}")

    async def dismiss_all_notifications(self):
        """清除所有通知"""
        if not self._redis:
            return
        try:
            await self._redis.delete(NOTIFICATIONS_KEY)
        except Exception:
            pass


cache = RedisCache()