"""
LLM Inference Server main application using LitServe framework.
"""
import litserve as ls
import yaml
import logging
import os
from pathlib import Path
from fastapi.middleware.cors import CORSMiddleware
from huggingface_hub import login
from .routes import router, init_router
from .api import InferenceApi

# Store process list globally so it doesn't get garbage collected
_WORKER_PROCESSES = []
_MANAGER = None

def setup_logging():
    """Set up basic logging configuration"""
    logging.basicConfig(
        level=logging.INFO,
        format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
    )
    return logging.getLogger(__name__)

def load_config():
    """Load configuration from config.yaml"""
    config_path = Path(__file__).parent / "config.yaml"
    with open(config_path) as f:
        return yaml.safe_load(f)

def create_app():
    """Create and configure the application instance."""
    global _WORKER_PROCESSES, _MANAGER

    logger = setup_logging()

    # Log into Hugging Face Hub
    access_token = os.environ.get("InferenceAPI")
    if access_token:
        try:
            login(token=access_token)
            logger.info("Successfully logged into Hugging Face Hub")
        except Exception as e:
            logger.error(f"Failed to login to Hugging Face Hub: {str(e)}")
    else:
        logger.warning("No Hugging Face access token found")

    config = load_config()
    server_config = config.get('server', {})

    # Initialize API with config
    api = InferenceApi(config)

    # Initialize router with API instance
    init_router(api)

    # Create LitServer instance
    server = ls.LitServer(
        api,
        timeout=server_config.get('timeout', 60),
        max_batch_size=server_config.get('max_batch_size', 1),
        track_requests=True
    )

    # Launch inference workers (assuming single uvicorn worker for now)
    _MANAGER, _WORKER_PROCESSES = server.launch_inference_worker(num_uvicorn_servers=1)

    # Get the FastAPI app
    app = server.app

    # Add CORS middleware
    app.add_middleware(
        CORSMiddleware,
        allow_origins=["*"],
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )

    # Add routes with configured prefix
    api_prefix = config.get('llm_server', {}).get('api_prefix', '/api/v1')
    app.include_router(router, prefix=api_prefix)

    # Set the response queue ID for the app
    app.response_queue_id = 0  # Since we're using a single worker

    return app

# Create the app instance for uvicorn
app = create_app()