import os
import yaml
from typing import Dict, Any
from pydantic import BaseModel


class DatabaseConfig(BaseModel):
    """数据库配置"""
    host: str
    port: int = 3306
    username: str
    password: str
    database: str
    charset: str = "utf8mb4"


class AppConfig(BaseModel):
    """应用配置"""
    name: str
    debug: bool = False
    host: str = "localhost"
    port: int = 12315
    database: DatabaseConfig


class Settings:
    """配置管理器"""
    
    def __init__(self):
        self._config: AppConfig = None
        self._env = os.getenv("ENVIRONMENT", "development")
        self.load_config()
    
    def load_config(self):
        """加载配置文件"""
        config_file = f"config/{self._env}.yaml"
        
        if not os.path.exists(config_file):
            raise FileNotFoundError(f"配置文件不存在: {config_file}")
        
        with open(config_file, 'r', encoding='utf-8') as f:
            config_data = yaml.safe_load(f)
        
        # 解析数据库配置
        db_config = DatabaseConfig(**config_data['database'])
        
        # 解析应用配置
        app_data = config_data['app']
        app_data['database'] = db_config
        
        self._config = AppConfig(**app_data)
    
    @property
    def config(self) -> AppConfig:
        """获取配置"""
        return self._config
    
    @property
    def environment(self) -> str:
        """获取当前环境"""
        return self._env
    
    @property
    def database_url(self) -> str:
        """获取数据库连接URL"""
        db = self._config.database
        return f"mysql+pymysql://{db.username}:{db.password}@{db.host}:{db.port}/{db.database}?charset={db.charset}"


# 全局配置实例
settings = Settings()