import os
from typing import Optional

class Config:
    """Configuration class for the chatbot"""
    
    # OpenAI Configuration
    OPENAI_API_KEY: str = os.getenv("OPENAI_API_KEY", "")
    OPENAI_MODEL: str = os.getenv("OPENAI_MODEL", "gpt-3.5-turbo")
    MAX_TOKENS: int = int(os.getenv("MAX_TOKENS", "500"))
    TEMPERATURE: float = float(os.getenv("TEMPERATURE", "0.7"))
    
    # System prompt
    SYSTEM_PROMPT: str = os.getenv(
        "SYSTEM_PROMPT", 
        "You are a helpful and friendly AI assistant with knowledge about Health Tech Hub Copenhagen. Use the provided PDF information when relevant to answer questions accurately and comprehensively. Keep your responses concise and engaging."
    )
    
    # Gradio Configuration
    GRADIO_THEME: str = "soft"
    GRADIO_HEIGHT: int = 500
    GRADIO_TITLE: str = "AI Chatbot"
    
    @classmethod
    def validate(cls) -> bool:
        """Validate that required configuration is present"""
        if not cls.OPENAI_API_KEY:
            raise ValueError(
                "OPENAI_API_KEY environment variable is required. "
                "Please set it before running the application."
            )
        return True