// Copyright 2021 COMIT Network.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
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// and/or sell copies of the Software, and to permit persons to whom the
// 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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//
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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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#![doc = include_str!("../README.md")]

use futures::StreamExt;
use libp2p::{
    identify, noise, ping, rendezvous,
    swarm::{NetworkBehaviour, SwarmEvent},
    tcp, yamux,
};
use std::error::Error;
use std::time::Duration;
use tracing_subscriber::EnvFilter;

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
    let _ = tracing_subscriber::fmt()
        .with_env_filter(EnvFilter::from_default_env())
        .try_init();

    // Results in PeerID 12D3KooWDpJ7As7BWAwRMfu1VU2WCqNjvq387JEYKDBj4kx6nXTN which is
    // used as the rendezvous point by the other peer examples.
    let keypair = libp2p::identity::Keypair::ed25519_from_bytes([0; 32]).unwrap();

    let mut swarm = libp2p::SwarmBuilder::with_existing_identity(keypair)
        .with_tokio()
        .with_tcp(
            tcp::Config::default(),
            noise::Config::new,
            yamux::Config::default,
        )?
        .with_behaviour(|key| MyBehaviour {
            identify: identify::Behaviour::new(identify::Config::new(
                "rendezvous-example/1.0.0".to_string(),
                key.public(),
            )),
            rendezvous: rendezvous::server::Behaviour::new(rendezvous::server::Config::default()),
            ping: ping::Behaviour::new(ping::Config::new().with_interval(Duration::from_secs(1))),
        })?
        .with_swarm_config(|cfg| cfg.with_idle_connection_timeout(Duration::from_secs(5)))
        .build();

    let _ = swarm.listen_on("/ip4/0.0.0.0/tcp/62649".parse().unwrap());

    while let Some(event) = swarm.next().await {
        match event {
            SwarmEvent::ConnectionEstablished { peer_id, .. } => {
                tracing::info!("Connected to {}", peer_id);
            }
            SwarmEvent::ConnectionClosed { peer_id, .. } => {
                tracing::info!("Disconnected from {}", peer_id);
            }
            SwarmEvent::Behaviour(MyBehaviourEvent::Rendezvous(
                rendezvous::server::Event::PeerRegistered { peer, registration },
            )) => {
                tracing::info!(
                    "Peer {} registered for namespace '{}'",
                    peer,
                    registration.namespace
                );
            }
            SwarmEvent::Behaviour(MyBehaviourEvent::Rendezvous(
                rendezvous::server::Event::DiscoverServed {
                    enquirer,
                    registrations,
                },
            )) => {
                tracing::info!(
                    "Served peer {} with {} registrations",
                    enquirer,
                    registrations.len()
                );
            }
            other => {
                tracing::debug!("Unhandled {:?}", other);
            }
        }
    }

    Ok(())
}

#[derive(NetworkBehaviour)]
struct MyBehaviour {
    identify: identify::Behaviour,
    rendezvous: rendezvous::server::Behaviour,
    ping: ping::Behaviour,
}