from typing import Any, Callable

from starlette.background import BackgroundTasks as StarletteBackgroundTasks
from typing_extensions import Annotated, Doc, ParamSpec # type: ignore [attr-defined]

P = ParamSpec("P")


class BackgroundTasks(StarletteBackgroundTasks):
 """
 A collection of background tasks that will be called after a response has been
 sent to the client.

 Read more about it in the
 [FastAPI docs for Background Tasks](https://fastapi.tiangolo.com/tutorial/background-tasks/).

 ## Example

 ```python
 from fastapi import BackgroundTasks, FastAPI

 app = FastAPI()


 def write_notification(email: str, message=""):
 with open("log.txt", mode="w") as email_file:
 content = f"notification for {email}: {message}"
 email_file.write(content)


 @app.post("/send-notification/{email}")
 async def send_notification(email: str, background_tasks: BackgroundTasks):
 background_tasks.add_task(write_notification, email, message="some notification")
 return {"message": "Notification sent in the background"}
 ```
 """

 def add_task(
 self,
 func: Annotated[
 Callable[P, Any],
 Doc(
 """
 The function to call after the response is sent.

 It can be a regular `def` function or an `async def` function.
 """
 ),
 ],
 *args: P.args,
 **kwargs: P.kwargs,
 ) -> None:
 """
 Add a function to be called in the background after the response is sent.

 Read more about it in the
 [FastAPI docs for Background Tasks](https://fastapi.tiangolo.com/tutorial/background-tasks/).
 """
 return super().add_task(func, *args, **kwargs)