from typing import List, Dict, Optional
from src.llm.factory import llm_factory, ProviderNotAvailableError
import logging

logger = logging.getLogger(__name__)

class ChatService:
    """Service for handling chat interactions with LLM providers"""

    def __init__(self):
        try:
            self.provider = llm_factory.get_provider()
        except ProviderNotAvailableError:
            self.provider = None
            logger.error("No LLM providers available")

    def generate_response(self, prompt: str, conversation_history: List[Dict]) -> Optional[str]:
        """Generate a response using the configured provider"""
        if not self.provider:
            raise ProviderNotAvailableError("No LLM provider available")

        try:
            return self.provider.generate(prompt, conversation_history)
        except Exception as e:
            logger.error(f"LLM generation failed: {e}")
            raise

    def stream_response(self, prompt: str, conversation_history: List[Dict]):
        """Stream a response using the configured provider"""
        if not self.provider:
            raise ProviderNotAvailableError("No LLM provider available")

        try:
            return self.provider.stream_generate(prompt, conversation_history)
        except Exception as e:
            logger.error(f"LLM stream generation failed: {e}")
            raise

# Global chat service instance
chat_service = ChatService()