"""FastAPI application for RAG backend."""

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from src.api.routes import router

app = FastAPI(
    title="RAG Document Assistant API",
    description="REST API for RAG-based document querying",
    version="1.0.0"
)

# CORS middleware for React frontend
# Allow Vercel deployments and local development
app.add_middleware(
    CORSMiddleware,
    allow_origins=[
        "http://localhost:5173",
        "http://localhost:5174",
        "http://localhost:5175",
        "http://127.0.0.1:5173",
        "http://127.0.0.1:5174",
        "http://127.0.0.1:5175",
    ],
    allow_origin_regex=r"https://.*\.(vercel\.app|hf\.space)",
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Include API routes
app.include_router(router, prefix="/api")


@app.get("/")
async def root():
    return {"message": "RAG Document Assistant API", "docs": "/docs"}