from fastapi import FastAPI, WebSocket, Depends, HTTPException
from auth import get_current_user, authenticate_user, create_access_token
from gen import generate_text_stream
from fastapi.security import OAuth2PasswordRequestForm
from fastapi.middleware.cors import CORSMiddleware
from middleware import setup_rate_limiter
import os

app = FastAPI()


# Apply rate limiting middleware
setup_rate_limiter(app)

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

# Login endpoint
@app.post("/token")
async def login(form_data: OAuth2PasswordRequestForm = Depends()):
    user = authenticate_user(form_data.username, form_data.password)
    if not user:
        raise HTTPException(status_code=400, detail="Incorrect username or password")
    access_token = create_access_token(data={"sub": user["username"]})
    return {"access_token": access_token, "token_type": "bearer"}

# WebSocket endpoint for streaming
@app.websocket("/generate")
async def websocket_generate(websocket: WebSocket, token: str):
    await websocket.accept()
    try:
        user = get_current_user(token)
        prompt = await websocket.receive_text()
        await generate_text_stream(prompt, websocket)
    except Exception as e:
        await websocket.send_text(f"Error: {str(e)}")
    finally:
        await websocket.close()