use derive_new::new;
use pin_project::pin_project;
use serde::{Deserialize, Serialize};
use serde_closure::traits::FnMut;
use std::{
pin::Pin, task::{Context, Poll}
};
use super::{ParallelPipe, ParallelStream, PipeTask, StreamTask};
#[pin_project]
#[derive(new)]
#[must_use]
pub struct Map<P, F> {
#[pin]
pipe: P,
f: F,
}
impl_par_dist! {
impl<P: ParallelStream, F, R> ParallelStream for Map<P, F>
where
F: FnMut<(P::Item,), Output = R> + Clone + Send + 'static,
{
type Item = R;
type Task = MapTask<P::Task, F>;
fn size_hint(&self) -> (usize, Option<usize>) {
self.pipe.size_hint()
}
fn next_task(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Self::Task>> {
let self_ = self.project();
let f = self_.f;
self_.pipe.next_task(cx).map(|task| {
task.map(|task| {
let f = f.clone();
MapTask { task, f }
})
})
}
}
impl<P: ParallelPipe<Input>, F, R, Input> ParallelPipe<Input> for Map<P, F>
where
F: FnMut<(P::Output,), Output = R> + Clone + Send + 'static,
{
type Output = R;
type Task = MapTask<P::Task, F>;
fn task(&self) -> Self::Task {
let task = self.pipe.task();
let f = self.f.clone();
MapTask { task, f }
}
}
}
#[pin_project]
#[derive(Serialize, Deserialize)]
pub struct MapTask<C, F> {
#[pin]
task: C,
f: F,
}
impl<C: StreamTask, F, R> StreamTask for MapTask<C, F>
where
F: FnMut<(C::Item,), Output = R> + Clone,
{
type Item = R;
type Async = crate::pipe::Map<C::Async, F>;
fn into_async(self) -> Self::Async {
crate::pipe::Map::new(self.task.into_async(), self.f)
}
}
impl<C: PipeTask<Input>, F, R, Input> PipeTask<Input> for MapTask<C, F>
where
F: FnMut<(C::Output,), Output = R> + Clone,
{
type Output = R;
type Async = crate::pipe::Map<C::Async, F>;
fn into_async(self) -> Self::Async {
crate::pipe::Map::new(self.task.into_async(), self.f)
}
}