app/main.py

from fastapi import FastAPI
from fastapi.requests import Request
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
from app.api.routes import chat, documents, health
from app.api.middleware.cors import setup_cors
from app.api.middleware.error_handler import error_handler_middleware
from app.api.middleware.logging import logging_middleware
from app.db.redis_client import RedisClient
from app.db.mongodb import MongoDB
from app.db.vector_store import vector_store
from app.utils.logger import logger
from app.config import config
from contextlib import asynccontextmanager


@asynccontextmanager
async def lifespan(app: FastAPI):
    logger.info("Starting RAG Chatbot application...")
    
    redis_client = RedisClient()
    await redis_client.connect()
    logger.info("Redis connected")
    
    mongodb = MongoDB()
    try:
        await mongodb.connect()
        logger.info("MongoDB connected")
    except Exception as e:
        logger.warning(f"MongoDB connection failed: {str(e)}")
    
    try:
        vector_store.create_collection()
        logger.info("Qdrant collection ready")
    except Exception as e:
        logger.warning(f"Qdrant setup warning: {str(e)}")
    
    yield
    
    await redis_client.disconnect()
    logger.info("Redis disconnected")
    
    try:
        await mongodb.disconnect()
        logger.info("MongoDB disconnected")
    except:
        pass
    
    logger.info("Application shutdown complete")


app = FastAPI(
    title=config["app"]["app"]["name"],
    version=config["app"]["app"]["version"],
    description="Enterprise RAG Chatbot with LangChain and LangGraph",
    lifespan=lifespan
)

setup_cors(app)

app.middleware("http")(error_handler_middleware)
app.middleware("http")(logging_middleware)

app.include_router(chat.router)
app.include_router(documents.router)
app.include_router(health.router)

app.mount("/static", StaticFiles(directory="frontend/static"), name="static")
templates = Jinja2Templates(directory="frontend/templates")


@app.get("/")
async def root(request: Request):
    return templates.TemplateResponse("index.html", {"request": request})


if __name__ == "__main__":
    import uvicorn
    uvicorn.run(
        "app.main:app",
        host=config["app"]["server"]["host"],
        port=config["app"]["server"]["port"],
        reload=config["app"]["app"]["debug"]
    )