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pub mod policy;
pub mod stream;

pub use stream::Stream;

use std::time::Duration;

pub enum Decision<Response> {
    Retry(Duration),
    Break(Response),
}

pub trait Policy<Response, TransformedResponse> {
    fn decide(&mut self, response: Response) -> Decision<TransformedResponse>;
}

#[cfg(feature = "tokio")]
pub async fn tokio_retry<S, P, Req, Res>(stream: S, mut policy: P, request: Req) -> Res
where
    S: Stream<Req>,
    P: Policy<<S as Stream<Req>>::Response, Res>,
    Req: Clone,
{
    loop {
        match policy.decide(stream.next(request.clone()).await) {
            Decision::Retry(delay) => tokio::time::sleep(delay).await,
            Decision::Break(response) => break response,
        }
    }
}