"""
Redis 连接管理模块

提供 Redis 连接池和基础操作。
"""
import redis.asyncio as redis
from typing import Optional

from core.config import settings
from logger.logging import get_logger

logger = get_logger(__name__)

# Redis 连接池
_redis_pool: Optional[redis.Redis] = None


async def get_redis() -> redis.Redis:
    """获取 Redis 连接"""
    global _redis_pool
    
    if _redis_pool is None:
        _redis_pool = redis.Redis(
            host=settings.redis_host,
            port=settings.redis_port,
            password=settings.redis_password or None,
            db=settings.redis_db,
            decode_responses=True,
        )
        logger.info(f"Redis 连接已建立: {settings.redis_host}:{settings.redis_port}")
    
    return _redis_pool


async def close_redis():
    """关闭 Redis 连接"""
    global _redis_pool
    
    if _redis_pool is not None:
        await _redis_pool.close()
        _redis_pool = None
        logger.info("Redis 连接已关闭")


class RedisService:
    """Redis 服务类"""
    
    @staticmethod
    async def set(key: str, value: str, expire: int = None) -> bool:
        """设置键值对"""
        r = await get_redis()
        await r.set(key, value, ex=expire)
        return True
    
    @staticmethod
    async def get(key: str) -> Optional[str]:
        """获取值"""
        r = await get_redis()
        return await r.get(key)
    
    @staticmethod
    async def delete(key: str) -> bool:
        """删除键"""
        r = await get_redis()
        await r.delete(key)
        return True
    
    @staticmethod
    async def exists(key: str) -> bool:
        """检查键是否存在"""
        r = await get_redis()
        return await r.exists(key) > 0
    
    @staticmethod
    async def ttl(key: str) -> int:
        """获取键的剩余过期时间（秒）"""
        r = await get_redis()
        return await r.ttl(key)
    
    @staticmethod
    async def incr(key: str) -> int:
        """递增键的值"""
        r = await get_redis()
        return await r.incr(key)