use serde::{Deserialize, Serialize};

use thiserror::Error;

#[serde(transparent)]

pub struct PublicKey(pub ed25519::VerificationKey);

#[derive(Error, Debug)]

pub enum PublicKeyError {

    #[error("invalid length {0}")]

    }

}

impl PublicKey {

    pub fn encode(&self) -> String {

        multibase::encode(multibase::Base::Base58Btc, &self.0)

    for r in refs {

        let (id, refname) = parse_ref::<UserId>(r.name())?;

        let entry = remotes

            .or_insert_with(|| Remote::new(id, HashMap::default()));

        entry.refs.insert(refname.to_string(), r.oid().into());

        let mut hm = HashSet::new();

        assert!(!hm.insert(a));

        assert!(!hm.insert(b));

    }

use crate::address_manager::AddressManager;

use crate::clock::RefClock;

use crate::collections::{HashMap, HashSet};

use crate::decoder::Decoder;

use crate::identity::{ProjId, UserId};

use crate::storage::{self, WriteRepository};

use crate::storage::{Inventory, ReadStorage, Remotes, Unverified, WriteStorage};

/// Network routing table. Keeps track of where projects are hosted.

/// Seconds since epoch.

pub type Timestamp = u64;

pub enum Message {

    /// Say hello to a peer. This is the first message sent to a peer after connection.

    Hello {

        timestamp: Timestamp,

        version: u32,

        addrs: Vec<Address>,

        timestamp: Timestamp,

        /// Original peer this inventory came from. We don't set this when we

        /// are the originator, only when relaying.

    },

}

}

impl Message {

        Self::Hello {

            timestamp,

            version: PROTOCOL_VERSION,

            addrs,

        }

    }

    where

        T: storage::ReadStorage,

    {

}

#[derive(Debug)]

    /// Peers currently or recently connected.

    peers: Peers,

    /// Protocol state that isn't peer-specific.

    /// Whether our local inventory no long represents what we have announced to the network.

    out_of_sync: bool,

    /// Last time the protocol was idle.

    start_time: LocalTime,

}

        let addrmgr = AddressManager::new(addresses);

        Self {

            peers: Peers::new(rng),

            out_of_sync: false,

            last_idle: LocalTime::default(),

        }

    }

            self.context.disconnect(addr, reason);

        }

    }

    pub fn providers(&self, proj: &ProjId) -> Box<dyn Iterator<Item = &Peer> + '_> {

        if let Some(peers) = self.routing.get(proj) {

        } else {

            Box::new(std::iter::empty())

        }

    /// Returns a sorted list from the closest peer to the furthest.

    /// Peers with more trackings in common score score higher.

    #[allow(unused)]

        todo!()

    }

                .context

                .routing

                .get(proj)

        }

    }

    }

}

where

    T: ReadStorage + WriteStorage + 'static,

    S: address_book::Store,

{

    type Event = ();

    type Command = Command;

    }

    fn attempted(&mut self, addr: &std::net::SocketAddr) {

        let persistent = self.context.config.is_persistent(addr);

        let mut peer = self

            .peers

            .or_insert_with(|| Peer::new(*addr, Link::Outbound, persistent));

        peer.attempts += 1;

        _local_addr: &std::net::SocketAddr,

        link: Link,

    ) {

        // For outbound connections, we are the first to say "Hello".

        // For inbound connections, we wait for the remote to say "Hello" first.

        if link.is_outbound() {

            let git = self.config.git_url.clone();

                self.context.write_all(

                    peer.addr,

                    [

                        Message::hello(

                            self.context.timestamp(),

                            self.context.config.listen.clone(),

                            git,

            }

        } else {

            self.peers.insert(

                Peer::new(

                    addr,

                    Link::Inbound,

        reason: nakamoto::DisconnectReason<Self::DisconnectReason>,

    ) {

        let since = self.local_time();

            peer.state = PeerState::Disconnected { since };

            // Attempt to re-connect to persistent peers.

                }

                // TODO: Eventually we want a delay before attempting a reconnection,

                // with exponential back-off.

                // TODO: Try to reconnect only if the peer was attempted. A disconnect without

                // even a successful attempt means that we're unlikely to be able to reconnect.

                Ok(Some(msg)) => {

                    let peers = negotiated

                        .iter()

                        .map(|(_, addr)| *addr)

                        .collect::<Vec<_>>();

    }

}

    fn deref(&self) -> &Self::Target {

        &self.context

    }

}

    fn deref_mut(&mut self) -> &mut Self::Target {

        &mut self.context

    }

    }

}

    type Item = Io<(), DisconnectReason>;

    fn next(&mut self) -> Option<Self::Item> {

    /// Whether the project was found locally or not.

    pub local: Option<Remotes<Unverified>>,

    /// A list of remote peers on which the project is known to exist.

}

/// Global protocol state used across peers.

#[derive(Debug)]

    /// Protocol configuration.

    config: Config,

    /// Tracks the location of projects.

    routing: Routing,

    /// Outgoing I/O queue.

    rng: Rng,

}

where

    T: storage::ReadStorage + storage::WriteStorage,

{

    pub(crate) fn new(

        config: Config,

        clock: RefClock,

        storage: T,

        addrmgr: AddressManager<S>,

        rng: Rng,

    ) -> Self {

        Self {

            config,

            clock,

            routing: HashMap::with_hasher(rng.clone().into()),

            io: VecDeque::new(),

        }

    }

    /// Process a peer inventory announcement by updating our routing table.

        for proj_id in inventory {

            let inventory = self

                .routing

    }

}

    /// Get current local timestamp.

    pub(crate) fn timestamp(&self) -> Timestamp {

        self.clock.local_time().as_secs()

}

#[derive(Debug)]

impl Peers {

    pub fn new(rng: Rng) -> Self {

        Self(AddressBook::new(rng))

    }

    /// Iterator over fully negotiated peers.

    pub fn negotiated(&self) -> impl Iterator<Item = (&IpAddr, &Peer)> + Clone {

        self.0.iter().filter(move |(_, p)| p.is_negotiated())

}

impl Deref for Peers {

    fn deref(&self) -> &Self::Target {

        &self.0

}

#[derive(Debug, Default)]

enum PeerState {

    /// Initial peer state. For outgoing peers this

    /// means we've attempted a connection. For incoming

    Initial,

    /// State after successful handshake.

    Negotiated {

        since: LocalTime,

        /// Addresses this peer is reachable on.

        addrs: Vec<Address>,

        }

    }

        self.addr.ip()

    }

        matches!(self.state, PeerState::Negotiated { .. })

    }

        &mut self,

        envelope: Envelope,

    ) -> Result<Option<Message>, PeerError>

    where

        T: storage::ReadStorage + storage::WriteStorage,

    {

        if envelope.magic != NETWORK_MAGIC {

            return Err(PeerError::WrongMagic(envelope.magic));

        }

        match (&self.state, envelope.msg) {

            (

                PeerState::Initial,

                Message::Hello {

                    timestamp,

                    version,

                    addrs,

                    ctx.write_all(

                        self.addr,

                        [

                            Message::get_inventory([]),

                        ],

                    );

                // set after the first message is received only. Setting it here would

                // mean that messages received right after the handshake could be ignored.

                self.state = PeerState::Negotiated {

                    since: ctx.clock.local_time(),

                    addrs,

                    git,

            (PeerState::Initial, _) => {

                debug!(

                    "Disconnecting peer {} for sending us a message before handshake",

                );

                return Err(PeerError::Misbehavior);

            }

                ctx.write(self.addr, inventory);

            }

            (

                Message::Inventory {

                    timestamp,

                    inv,

                } else {

                    return Ok(None);

                }

                if ctx.config.relay {

                    return Ok(Some(Message::Inventory {

                        timestamp,

                        inv,

                    }));

                }

            }

            (PeerState::Negotiated { .. }, Message::Hello { .. }) => {

                debug!(

                    "Disconnecting peer {} for sending us a redundant handshake message",

                );

                return Err(PeerError::Misbehavior);

            }

            (PeerState::Disconnected { .. }, msg) => {

            }

        }

        Ok(None)

            let name = r.name().ok_or(Error::InvalidRef)?;

            let (id, refname) = git::parse_ref::<UserId>(name)?;

            let entry = remotes

                .or_insert_with(|| Remote::new(id, HashMap::default()));

            let oid = r.target().ok_or(Error::InvalidRef)?;

pub(crate) mod arbitrary;

pub(crate) mod assert;

pub(crate) mod fixtures;

pub(crate) mod logger;

pub(crate) mod peer;

use crate::decoder::Decoder;

use crate::protocol::*;

use crate::storage::{ReadStorage, WriteStorage};

use crate::*;

/// Protocol instantiation used for testing.

#[derive(Debug)]

pub struct Peer<S> {

        ip: impl Into<net::IpAddr>,

        addrs: Vec<(net::SocketAddr, Source)>,

        storage: S,

    ) -> Self {

        let addrs = addrs

            .into_iter()

            .collect();

        let local_time = LocalTime::now();

        let clock = RefClock::from(local_time);

        let ip = ip.into();

        let local_addr = net::SocketAddr::new(ip, rng.u16(..));

        self.config().git_url.clone()

    }

    pub fn receive(&mut self, peer: &net::SocketAddr, msg: Message) {

        let bytes = serde_json::to_vec(&Envelope {

            magic: NETWORK_MAGIC,

        self.protocol.received_bytes(peer, &bytes);

    }

        let local = net::SocketAddr::new(self.ip, self.rng.u16(..));

        let git = format!("file://{}.git", remote.ip());

        let git = Url::from_bytes(git.as_bytes()).unwrap();

        self.initialize();

        self.receive(

            Message::hello(

                self.local_time().as_secs(),

                git,

            ),

        );

        msgs.find(|m| matches!(m, Message::Hello { .. }))

            .expect("`hello` is sent");

        msgs.find(|m| matches!(m, Message::GetInventory { .. }))

        self.receive(

            &remote,

            Message::hello(

                self.local_time().as_secs(),

                peer.config().listen.clone(),

                git,

    let bob = Peer::new("bob", [9, 9, 9, 9], MockStorage::empty());

    let eve = Peer::new("eve", [7, 7, 7, 7], MockStorage::empty());

    let peers = alice

        .protocol

    alice.connected(bob.addr(), &local, Link::Inbound);

    alice.receive(

        &bob.addr(),

    );

    assert_matches!(alice.outbox().next(), Some(Io::Disconnect(addr, _)) if addr == bob.addr());

}

    for proj in &projs {

        let providers = alice.routing().get(proj).unwrap();

    }

    let a = alice

    // Inventory from Bob relayed to Eve.

    alice.connect_to(&bob);

    alice.receive(

        &bob.addr(),

        Message::Inventory {

    assert_matches!(

        alice.messages(&eve.addr()).next(),

        Some(Message::Inventory { timestamp, origin, .. })

    );

    assert_matches!(

        alice.messages(&bob.addr()).next(),

    assert_matches!(

        alice.messages(&eve.addr()).next(),

        Some(Message::Inventory { timestamp, origin, .. })

        "Sending a new inventory does trigger the relay"

    );

    assert_matches!(

        alice.messages(&bob.addr()).next(),

        Some(Message::Inventory { timestamp, origin, .. })

    );

}

        let mut routing = Routing::with_hasher(rng.clone().into());

        for (inv, peer) in &[

        ] {

            for (proj, _) in inv {

                routing

        eve.command(Command::Connect(alice.addr()));

        eve.command(Command::Connect(bob.addr()));

            .into_iter()

            .collect();

        let mut simulator = Simulation::new(LocalTime::now(), rng, simulator::Options::default())