import os
from dotenv import load_dotenv
from typing import Optional

# 加载环境变量
load_dotenv()

class Settings:
    # 应用配置
    APP_NAME: str = "LangChain Ollama API"
    APP_VERSION: str = "1.0.0"
    APP_DESCRIPTION: str = "基于 Ollama 本地大模型和 LangChain 的 AI 服务 API"
    API_PREFIX: str = os.getenv("API_PREFIX", "/api/v1")
    
    # 服务器配置
    HOST: str = os.getenv("HOST", "0.0.0.0")
    PORT: int = int(os.getenv("PORT", "5000"))
    DEBUG: bool = os.getenv("DEBUG", "False").lower() == "true"
    
    # Ollama 配置
    OLLAMA_BASE_URL: str = os.getenv("OLLAMA_BASE_URL", "http://localhost:11434")
    DEFAULT_MODEL: str = os.getenv("DEFAULT_MODEL", "qwen2.5:latest")
    TEMPERATURE: float = float(os.getenv("TEMPERATURE", "0.7"))
    MAX_TOKENS: int = int(os.getenv("MAX_TOKENS", "2048"))
    
    # 安全配置
    CORS_ORIGINS: list = ["*"]
    CORS_CREDENTIALS: bool = True
    CORS_METHODS: list = ["*"]
    CORS_HEADERS: list = ["*"]
    
    # 日志配置
    LOG_LEVEL: str = "INFO" if DEBUG else "WARNING"
    LOG_FORMAT: str = "%(asctime)s - %(name)s - %(levelname)s - %(message)s"
    
    class Config:
        case_sensitive = True

# 创建全局配置实例
settings = Settings()