"""
配置管理模块

支持多环境配置切换：
- TEST_ENV=local  使用本地配置（默认）
- TEST_ENV=remote 使用远程配置
"""
import os
from pathlib import Path
from typing import Any, Optional

import yaml


class Settings:
    """配置管理器"""
    
    _instance: Optional['Settings'] = None
    _config: dict = {}
    
    def __new__(cls):
        if cls._instance is None:
            cls._instance = super().__new__(cls)
            cls._instance._load_config()
        return cls._instance
    
    def _load_config(self):
        """加载配置文件"""
        env = os.getenv("TEST_ENV", "local")
        config_dir = Path(__file__).parent
        config_file = config_dir / f"{env}.yaml"
        
        if not config_file.exists():
            raise FileNotFoundError(f"配置文件不存在: {config_file}")
        
        with open(config_file, "r", encoding="utf-8") as f:
            self._config = yaml.safe_load(f)
        
        print(f"[配置] 已加载 {env} 环境配置")
    
    def get(self, key: str, default: Any = None) -> Any:
        """
        获取配置值，支持点号分隔的路径
        
        示例：
            settings.get("api.base_url")
            settings.get("database.host")
        """
        keys = key.split(".")
        value = self._config
        
        for k in keys:
            if isinstance(value, dict):
                value = value.get(k)
            else:
                return default
            
            if value is None:
                return default
        
        return value
    
    @property
    def api_base_url(self) -> str:
        return self.get("api.base_url", "http://localhost:3000")
    
    @property
    def api_timeout(self) -> int:
        return self.get("api.timeout", 30)
    
    @property
    def db_config(self) -> dict:
        return {
            "host": self.get("database.host", "localhost"),
            "port": self.get("database.port", 5432),
            "database": self.get("database.name", "junhong_dev"),
            "user": self.get("database.user", "postgres"),
            "password": self.get("database.password", "postgres"),
        }
    
    @property
    def redis_config(self) -> dict:
        return {
            "host": self.get("redis.host", "localhost"),
            "port": self.get("redis.port", 6379),
            "db": self.get("redis.db", 0),
        }
    
    def get_account(self, role: str) -> dict:
        """获取预置账号信息"""
        return self.get(f"accounts.{role}", {})


# 全局配置实例
settings = Settings()