main.py

import asyncio
from contextlib import asynccontextmanager

from fastapi import FastAPI, Request
from fastapi.middleware.gzip import GZipMiddleware
from fastapi.responses import RedirectResponse
from fastapi.staticfiles import StaticFiles

from app.config import IS_PRODUCTION, templates
from app.database import db
from app.routers import paste, user
from app.utils import AuthMiddleware


async def background_cleanup():
    while True:
        try:
            await asyncio.sleep(7200)
            deleted = await db.delete_expired_pastes()
            if deleted > 0:
                print(f"Cleaned up {deleted} expired pastes.")
        except asyncio.CancelledError:
            return
        except Exception as e:
            print(f"Cleanup error: {e}")
            await asyncio.sleep(600)


async def background_view_flush():
    while True:
        try:
            await asyncio.sleep(120)
            await paste.flush_views_buffer()
        except asyncio.CancelledError:
            return
        except Exception as e:
            print(f"View flush error: {e}")
            await asyncio.sleep(60)


@asynccontextmanager
async def lifespan(app: FastAPI):
    await db.connect()
    cleanup_task = asyncio.create_task(background_cleanup())
    view_task = asyncio.create_task(background_view_flush())
    yield
    cleanup_task.cancel()
    view_task.cancel()
    await paste.flush_views_buffer()
    await db.close()


app = FastAPI(lifespan=lifespan, docs_url=None, redoc_url=None)
app.add_middleware(AuthMiddleware)
if not IS_PRODUCTION:
    app.add_middleware(GZipMiddleware, minimum_size=5_000)
    app.mount("/static", StaticFiles(directory="static"), name="static")


app.include_router(user.router)
app.include_router(paste.api_router)
app.include_router(paste.router)


@app.exception_handler(303)
async def redirect_303_handler(request: Request, __):
    return RedirectResponse(url="/login", status_code=303)


@app.exception_handler(404)
async def not_found_handler(request: Request, __):
    return templates.TemplateResponse("404.html", {"request": request}, status_code=404)