app/main.py

import logging

import gradio as gr
from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from slowapi import _rate_limit_exceeded_handler
from slowapi.errors import RateLimitExceeded
from slowapi.middleware import SlowAPIMiddleware

from app.config import DEMO_MODE
from app.middleware.rate_limit import auth_limiter, account_limiter
from app.routes import auth_routes, generate, brand_voice, history, account, payments, bulk
from app.legal import pages as legal_pages
from app.ui import build_ui

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger("etsy_optimizer")

app = FastAPI(title="Etsy Listing Optimizer API")

# --- CORS: explicit allowlist, never wide open --------------------------------
# For a same-origin Gradio+FastAPI deployment on a single HF Space this can
# stay empty/self-only; add your own domain here if you build a separate
# frontend that calls this API cross-origin.
app.add_middleware(
    CORSMiddleware,
    allow_origins=[],
    allow_credentials=True,
    allow_methods=["GET", "POST", "DELETE"],
    allow_headers=["Authorization", "Content-Type"],
)

# --- Rate limiting -------------------------------------------------------------
app.state.limiter = auth_limiter  # slowapi needs exactly one limiter on app.state;
# account_limiter shares the same in-memory backend semantics and is applied
# via its own decorator on /generate - both raise the same RateLimitExceeded.
app.add_exception_handler(RateLimitExceeded, _rate_limit_exceeded_handler)
app.add_middleware(SlowAPIMiddleware)


@app.exception_handler(Exception)
async def friendly_error_handler(request: Request, exc: Exception):
    # Last-resort catch-all: never leak a raw stack trace to the UI.
    logger.exception("Unhandled error on %s", request.url.path)
    return JSONResponse(status_code=500, content={"detail": "Something went wrong. Please try again."})


app.include_router(auth_routes.router, tags=["auth"])
app.include_router(generate.router, tags=["generate"])
app.include_router(brand_voice.router, tags=["brand-voice"])
app.include_router(history.router, tags=["history"])
app.include_router(account.router, tags=["account"])
app.include_router(payments.router, tags=["billing"])
app.include_router(bulk.router, tags=["bulk"])
app.include_router(legal_pages.router, tags=["legal"])


@app.get("/health")
async def health():
    return {"status": "ok", "demo_mode": DEMO_MODE}


# Mount the Gradio UI at the root path, on top of the FastAPI routes above.
#
# NOTE: deliberately NOT named `demo`. Hugging Face's Gradio SDK runtime
# scans app_file for a top-level `gr.Blocks`/`gr.Interface` variable named
# exactly `demo` and auto-launches it as its own standalone server, even
# though we never call .launch() ourselves. That collided with our explicit
# uvicorn process (server.py) on the next free port -> "address already in
# use: 7861". Renaming it opts this app out of that auto-launch behavior,
# since we're intentionally mounting it onto FastAPI instead.
gradio_ui = build_ui(app)
app = gr.mount_gradio_app(app, gradio_ui, path="/")