1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110

use futures::{pin_mut, stream};
use pin_project::pin_project;
use serde::{Deserialize, Serialize};
use std::{
	iter, ops::{Range, RangeFrom, RangeInclusive}, pin::Pin, task::{Context, Poll}
};

use super::{DistributedStream, IntoDistributedStream, StreamTask, StreamTaskAsync};
use crate::{pool::ProcessSend, sink::Sink};

pub trait IteratorExt: Iterator + Sized {
	fn dist(self) -> IterIter<Self> {
		IterIter(self)
	}
}
impl<I: Iterator + Sized> IteratorExt for I {}

pub struct IterIter<I>(pub(super) I);

impl<I: Iterator> DistributedStream for IterIter<I>
where
	I::Item: ProcessSend,
{
	type Item = I::Item;
	type Task = IterIterTask<I::Item>;

	fn size_hint(&self) -> (usize, Option<usize>) {
		self.0.size_hint()
	}
	fn next_task(&mut self) -> Option<Self::Task> {
		self.0.next().map(IterIterTask::new)
	}
}

#[pin_project]
#[derive(Serialize, Deserialize)]
pub struct IterIterTask<T>(Option<T>);
impl<T> IterIterTask<T> {
	fn new(t: T) -> Self {
		Self(Some(t))
	}
}

impl<T> StreamTask for IterIterTask<T> {
	type Item = T;
	type Async = IterIterTask<T>;

	fn into_async(self) -> Self::Async {
		self
	}
}
impl<T> StreamTaskAsync for IterIterTask<T> {
	type Item = T;

	fn poll_run(
		mut self: Pin<&mut Self>, cx: &mut Context, sink: Pin<&mut impl Sink<Self::Item>>,
	) -> Poll<()> {
		let stream = stream::iter(iter::from_fn(|| self.0.take()));
		pin_mut!(stream);
		sink.poll_forward(cx, stream)
	}
}

impl<Idx> IntoDistributedStream for Range<Idx>
where
	Self: Iterator,
	<Self as Iterator>::Item: ProcessSend,
{
	type DistStream = IterIter<Self>;
	type Item = <Self as Iterator>::Item;

	fn into_dist_stream(self) -> Self::DistStream
	where
		Self: Sized,
	{
		IterIter(self)
	}
}

impl<Idx> IntoDistributedStream for RangeFrom<Idx>
where
	Self: Iterator,
	<Self as Iterator>::Item: ProcessSend,
{
	type DistStream = IterIter<Self>;
	type Item = <Self as Iterator>::Item;

	fn into_dist_stream(self) -> Self::DistStream
	where
		Self: Sized,
	{
		IterIter(self)
	}
}

impl<Idx> IntoDistributedStream for RangeInclusive<Idx>
where
	Self: Iterator,
	<Self as Iterator>::Item: ProcessSend,
{
	type DistStream = IterIter<Self>;
	type Item = <Self as Iterator>::Item;

	fn into_dist_stream(self) -> Self::DistStream
	where
		Self: Sized,
	{
		IterIter(self)
	}
}