sark-h2 0.22.0

use core::convert::Infallible;
use sark_core::{
    decode::Decode,
    manifold::{schedule::typed, task::app::Runtime},
};
use sark_http::payload::response::status::Code;

use crate::{conn, frame::numbers};

pub(super) type Stored<'d, P, C, D> =
    o3::depot::queue::indexed::lanes::typed::Value<Response<'d, P, C, D>, Data<'d, D>, Infallible>;

type Progress<'d, R> = Result<
    typed::Control<
        Response<
            'd,
            <R as Decode>::Prepared,
            <R as Runtime<'d>>::Completion,
            <R as duplex::Application<'d>>::Duplex,
        >,
        Data<'d, <R as duplex::Application<'d>>::Duplex>,
        Infallible,
        conn::DataBlock,
        numbers::ErrorCode,
    >,
    numbers::ErrorCode,
>;

pub(super) mod deadline;
mod driver;
mod emission;
pub(in crate::server) mod expiry;
pub(super) mod input;
mod opening;
pub(super) mod raw;
pub(super) use driver::Driver;

pub(super) enum Count {
    Pending,
    Settled,
}

pub(super) enum Duplex<I, E = PushError<I, payload::Error>> {
    Other(I),
    Closed(payload::Error, I),
    Applied(Result<(), E>),
}

use o3::buffer::resident;
use sark_core::{
    body,
    decode::{exec, request},
    duplex::{
        self,
        input::{PushError, Status},
    },
    life,
    manifold::stream::Boundary,
};
use sark_http::payload::owned;

use crate::{
    conn::event,
    server::{
        payload,
        response::{Head, Pending, Receipt},
    },
};

pub(super) enum Response<'d, P, C, D: duplex::Session<'d>> {
    Status(Code),
    Sync(request::Ready<exec::Sync, P, owned::Segments<'d>>),
    Completion(C),
    Head {
        head: Head<'d>,
        outcome: life::Outcome,
        count: Count,
    },
    Encoded(Receipt<'d>),
    DuplexOpen {
        request: input::Request<'d, P>,
    },
    DuplexHead {
        head: Head<'d>,
        input: input::Input<'d, D>,
    },
}

pub(super) enum Data<'d, D: duplex::Session<'d>> {
    Body {
        pending: Pending<'d>,
        outcome: life::Outcome,
    },
    Duplex {
        input: input::Input<'d, D>,
    },
}

impl<'d, P, C, D> Response<'d, P, C, D>
where
    D: duplex::Session<'d>,
{
    pub(in crate::server::task) fn push(
        self,
        data: event::DataPayload<resident::Shared<'d>>,
        boundary: Boundary,
    ) -> (Self, Duplex<event::DataPayload<resident::Shared<'d>>>) {
        match self {
            Self::DuplexOpen { mut request } => match boundary {
                Boundary::More => {
                    let result = request.append(data).map_err(PushError::Buffer);
                    (Self::DuplexOpen { request }, Duplex::Applied(result))
                }
                Boundary::End => {
                    let (request, result) = match request.try_end(data) {
                        Ok(request) => (request, Ok(())),
                        Err((rejected, request)) => (request, Err(PushError::Buffer(rejected))),
                    };
                    (Self::DuplexOpen { request }, Duplex::Applied(result))
                }
            },
            Self::DuplexHead { head, mut input } if matches!(input.status(), Status::Open) => {
                let result = input.push(data, boundary);
                (Self::DuplexHead { head, input }, Duplex::Applied(result))
            }
            other @ Self::DuplexHead { .. } => (
                other,
                Duplex::Closed(payload::Error::Body(body::Error::InputFinished), data),
            ),
            other => (other, Duplex::Other(data)),
        }
    }

    pub(in crate::server::task) fn finish(self) -> (Self, Duplex<(), input::Error>) {
        match self {
            Self::DuplexOpen { request } => {
                let (request, result) = match request.try_finish() {
                    Ok(request) => (request, Ok(())),
                    Err(rejected) => {
                        let (request, error) = rejected.into_parts();
                        (request, Err(input::Error::Input(error)))
                    }
                };
                (Self::DuplexOpen { request }, Duplex::Applied(result))
            }
            Self::DuplexHead { head, mut input } if matches!(input.status(), Status::Open) => {
                let result = input.finish().map_err(input::Error::Machine);
                (Self::DuplexHead { head, input }, Duplex::Applied(result))
            }
            other @ Self::DuplexHead { .. } => (
                other,
                Duplex::Closed(payload::Error::Body(body::Error::InputFinished), ()),
            ),
            other => (other, Duplex::Other(())),
        }
    }
}

impl<'d, D: duplex::Session<'d>> Data<'d, D> {
    pub(in crate::server::task) fn push(
        self,
        data: event::DataPayload<resident::Shared<'d>>,
        boundary: Boundary,
    ) -> (Self, Duplex<event::DataPayload<resident::Shared<'d>>>) {
        match self {
            Self::Duplex { mut input } if matches!(input.status(), Status::Open) => {
                let result = input.push(data, boundary);
                (Self::Duplex { input }, Duplex::Applied(result))
            }
            other @ Self::Duplex { .. } => (
                other,
                Duplex::Closed(payload::Error::Body(body::Error::InputFinished), data),
            ),
            other @ Self::Body { .. } => (other, Duplex::Other(data)),
        }
    }

    pub(in crate::server::task) fn finish(self) -> (Self, Duplex<(), input::Error>) {
        match self {
            Self::Duplex { mut input } if matches!(input.status(), Status::Open) => {
                let result = input.finish().map_err(input::Error::Machine);
                (Self::Duplex { input }, Duplex::Applied(result))
            }
            other @ Self::Duplex { .. } => (
                other,
                Duplex::Closed(payload::Error::Body(body::Error::InputFinished), ()),
            ),
            other @ Self::Body { .. } => (other, Duplex::Other(())),
        }
    }
}