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
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139

use std::{
    collections::VecDeque,
    task::{Context, Poll},
};

use either::Either;
use libp2p::{
    core::Endpoint,
    swarm::{
        self, dummy, ConnectionDenied, ConnectionId, FromSwarm, NetworkBehaviour, PollParameters,
        THandler, THandlerInEvent, ToSwarm,
    },
    Multiaddr, PeerId, StreamProtocol,
};

mod handler;

#[derive(Default, Debug)]
pub struct Behaviour {
    events: VecDeque<ToSwarm<<Self as NetworkBehaviour>::ToSwarm, THandlerInEvent<Self>>>,
    protocol: Vec<StreamProtocol>,
    use_deprecated: bool,
}

impl Behaviour {
    pub fn iter(&self) -> impl Iterator<Item = String> + '_ {
        self.protocol.iter().map(|s| s.to_string())
    }
}

impl NetworkBehaviour for Behaviour {
    type ConnectionHandler = Either<handler::Handler, dummy::ConnectionHandler>;
    type ToSwarm = void::Void;

    fn handle_pending_inbound_connection(
        &mut self,
        _: ConnectionId,
        _: &Multiaddr,
        _: &Multiaddr,
    ) -> Result<(), ConnectionDenied> {
        Ok(())
    }

    fn handle_pending_outbound_connection(
        &mut self,
        _: ConnectionId,
        _: Option<PeerId>,
        _: &[Multiaddr],
        _: Endpoint,
    ) -> Result<Vec<Multiaddr>, ConnectionDenied> {
        Ok(vec![])
    }

    fn handle_established_inbound_connection(
        &mut self,
        _: ConnectionId,
        _: PeerId,
        _: &Multiaddr,
        _: &Multiaddr,
    ) -> Result<THandler<Self>, ConnectionDenied> {
        let handler = match self.use_deprecated {
            true => Either::Right(dummy::ConnectionHandler),
            false => Either::Left(handler::Handler::default()),
        };
        Ok(handler)
    }

    fn handle_established_outbound_connection(
        &mut self,
        _: ConnectionId,
        _: PeerId,
        _: &Multiaddr,
        _: Endpoint,
    ) -> Result<THandler<Self>, ConnectionDenied> {
        let handler = match self.use_deprecated {
            true => Either::Right(dummy::ConnectionHandler),
            false => Either::Left(handler::Handler::default()),
        };
        Ok(handler)
    }

    fn on_connection_handler_event(
        &mut self,
        _: PeerId,
        _: ConnectionId,
        event: swarm::THandlerOutEvent<Self>,
    ) {
        match event {
            Either::Left(handler::Out::Protocol(protocol)) => {
                if self.protocol.ne(&protocol) {
                    self.protocol = protocol;
                }
            }
            Either::Right(v) => void::unreachable(v),
        }
    }

    fn on_swarm_event(&mut self, event: FromSwarm<Self::ConnectionHandler>) {
        match event {
            FromSwarm::AddressChange(_)
            | FromSwarm::ConnectionEstablished(_)
            | FromSwarm::ConnectionClosed(_)
            | FromSwarm::DialFailure(_)
            | FromSwarm::ListenFailure(_)
            | FromSwarm::NewListener(_)
            | FromSwarm::NewListenAddr(_)
            | FromSwarm::ExpiredListenAddr(_)
            | FromSwarm::ListenerError(_)
            | FromSwarm::ListenerClosed(_)
            | FromSwarm::ExternalAddrConfirmed(_)
            | FromSwarm::ExternalAddrExpired(_)
            | FromSwarm::NewExternalAddrCandidate(_) => {}
        }
    }

    #[allow(deprecated)]
    fn poll(
        &mut self,
        _: &mut Context,
        params: &mut impl PollParameters,
    ) -> Poll<ToSwarm<Self::ToSwarm, THandlerInEvent<Self>>> {
        if self.use_deprecated {
            let supported_protocols = params
                .supported_protocols()
                .filter_map(|b| {
                    StreamProtocol::try_from_owned(String::from_utf8_lossy(&b).to_string()).ok()
                })
                .collect::<Vec<_>>();

            if supported_protocols.len() != self.protocol.len() {
                self.protocol = supported_protocols;
            }
        }
        if let Some(event) = self.events.pop_front() {
            return Poll::Ready(event);
        }
        Poll::Pending
    }
}