from collections.abc import AsyncIterator
from contextlib import asynccontextmanager

from fastapi import FastAPI, Request
from fastapi.responses import JSONResponse
from slowapi.errors import RateLimitExceeded
from slowapi.middleware import SlowAPIMiddleware

from app.config import get_settings
from app.db import close_pool, get_pool
from app.health import router as health_router
from app.logging_setup import configure_logging
from app.rate_limit import limiter
from app.routers.auth import router as auth_router
from app.routers.push import router as push_router
from app.routers.views import router as views_router


@asynccontextmanager
async def lifespan(_: FastAPI) -> AsyncIterator[None]:
    configure_logging()
    await get_pool()
    try:
        yield
    finally:
        await close_pool()


def _rate_limit_handler(request: Request, exc: Exception) -> JSONResponse:
    _ = request, exc
    return JSONResponse(status_code=429, content={"detail": "rate limit exceeded"})


def create_app(role: str) -> FastAPI:
    settings = get_settings()
    app = FastAPI(
        title=f"fleet-platform [{role}]",
        version=settings.app_git_sha,
        lifespan=lifespan,
    )
    app.state.limiter = limiter
    app.add_exception_handler(RateLimitExceeded, _rate_limit_handler)
    app.add_middleware(SlowAPIMiddleware)

    app.include_router(health_router)

    if role == "gateway":
        app.include_router(auth_router)
        app.include_router(push_router)
        app.include_router(views_router)

    return app