common.rs

//! `BitTorrent` protocol primitive types
//!
//! [BEP 3. The `BitTorrent` Protocol Specification](https://www.bittorrent.org/beps/bep_0003.html)
use aquatic_udp_protocol::{AnnounceEvent, NumberOfBytes};
use serde::{Deserialize, Serialize};

/// The maximum number of torrents that can be returned in an `scrape` response.
/// It's also the maximum number of peers returned in an `announce` response.
///
/// The [BEP 15. UDP Tracker Protocol for `BitTorrent`](https://www.bittorrent.org/beps/bep_0015.html)
/// defines this limit:
///
/// "Up to about 74 torrents can be scraped at once. A full scrape can't be done
/// with this protocol."
///
/// The [BEP 48. Tracker Protocol Extension: Scrape](https://www.bittorrent.org/beps/bep_0048.html)
/// does not specifically mention this limit, but the limit is being used for
/// both the UDP and HTTP trackers since it's applied at the domain level.
pub const MAX_SCRAPE_TORRENTS: u8 = 74;

/// HTTP tracker authentication key length.
///
/// See function to [`generate`](crate::tracker::auth::generate) the
/// [`ExpiringKeys`](crate::tracker::auth::ExpiringKey) for more information.
pub const AUTH_KEY_LENGTH: usize = 32;

#[repr(u32)]
#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
enum Actions {
    // todo: it seems this enum is not used anywhere. Values match the ones in
    // aquatic_udp_protocol::request::Request::from_bytes.
    Connect = 0,
    Announce = 1,
    Scrape = 2,
    Error = 3,
}

/// Announce events. Described on  the
/// [BEP 3. The `BitTorrent` Protocol Specification](https://www.bittorrent.org/beps/bep_0003.html)
#[derive(Serialize, Deserialize)]
#[serde(remote = "AnnounceEvent")]
pub enum AnnounceEventDef {
    /// The peer has started downloading the torrent.
    Started,
    /// The peer has ceased downloading the torrent.
    Stopped,
    /// The peer has completed downloading the torrent.
    Completed,
    /// This is one of the announcements done at regular intervals.
    None,
}

/// Number of bytes downloaded, uploaded or pending to download (left) by the peer.
#[derive(Serialize, Deserialize)]
#[serde(remote = "NumberOfBytes")]
pub struct NumberOfBytesDef(pub i64);