mixnet 0.4.0

// Copyright 2022 Parity Technologies (UK) Ltd.
//
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// copy of this software and associated documentation files (the "Software"),
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// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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//! Hop target type.

use super::packet::{PeerId, RawMixnodeIndex, MAX_MIXNODE_INDEX};
use std::fmt;

/// The index of a mixnode in a session's mixnode list. The index is always <=
/// [`MAX_MIXNODE_INDEX`].
#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub struct MixnodeIndex(RawMixnodeIndex);

impl MixnodeIndex {
	/// Get the raw index out. This will always be <= [`MAX_MIXNODE_INDEX`].
	pub fn get(self) -> RawMixnodeIndex {
		self.0
	}
}

impl TryFrom<usize> for MixnodeIndex {
	type Error = ();

	fn try_from(index: usize) -> Result<Self, Self::Error> {
		if index <= MAX_MIXNODE_INDEX as usize {
			Ok(Self(index as RawMixnodeIndex))
		} else {
			Err(())
		}
	}
}

impl TryFrom<RawMixnodeIndex> for MixnodeIndex {
	type Error = ();

	fn try_from(index: RawMixnodeIndex) -> Result<Self, Self::Error> {
		(index as usize).try_into()
	}
}

impl fmt::Display for MixnodeIndex {
	fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
		self.0.fmt(fmt)
	}
}

#[derive(Debug, PartialEq, Eq)]
pub enum Target {
	MixnodeIndex(MixnodeIndex),
	PeerId(PeerId),
}