"""配置读取客户端"""
import os
from typing import Optional, Any, Dict
from functools import lru_cache

from .http_client import PlatformHttpClient


class ConfigReader:
    """配置读取器
    
    从平台服务读取租户配置
    
    使用示例:
        config = ConfigReader(tenant_id=1)
        
        # 读取单个配置
        value = await config.get("wechat", "app_id")
        
        # 读取配置组
        wechat_config = await config.get_group("wechat")
    """
    
    def __init__(
        self,
        tenant_id: int,
        platform_url: Optional[str] = None,
        api_key: Optional[str] = None,
        cache_ttl: int = 300  # 缓存时间(秒)
    ):
        self.tenant_id = tenant_id
        self.platform_url = platform_url or os.getenv("PLATFORM_URL", "")
        self.api_key = api_key or os.getenv("PLATFORM_API_KEY", "")
        self.cache_ttl = cache_ttl
        
        self._client = PlatformHttpClient(
            base_url=self.platform_url,
            api_key=self.api_key
        )
        
        # 本地缓存
        self._cache: Dict[str, Any] = {}
    
    async def get(
        self,
        config_type: str,
        config_key: str,
        default: Any = None
    ) -> Any:
        """读取配置值
        
        Args:
            config_type: 配置类型
            config_key: 配置键
            default: 默认值
        
        Returns:
            配置值
        """
        cache_key = f"{config_type}:{config_key}"
        
        # 检查缓存
        if cache_key in self._cache:
            return self._cache[cache_key]
        
        # 从平台获取
        try:
            response = await self._client.get(
                f"/api/config/{config_type}/{config_key}",
                params={"tenant_id": self.tenant_id}
            )
            
            if response.status_code == 200:
                data = response.json()
                value = data.get("config_value", default)
                self._cache[cache_key] = value
                return value
            elif response.status_code == 404:
                return default
            else:
                raise Exception(f"Config read failed: {response.status_code}")
                
        except Exception as e:
            # 失败时返回默认值
            return default
    
    def get_env(
        self,
        env_key: str,
        default: Any = None
    ) -> Any:
        """从环境变量读取配置（同步方法）
        
        Args:
            env_key: 环境变量名
            default: 默认值
        
        Returns:
            配置值
        """
        return os.getenv(env_key, default)
    
    def clear_cache(self):
        """清除缓存"""
        self._cache.clear()