use std::{error::Error, time::Duration};

use cll2v0::messages::{MyRequest, MyResponse};
use futures::prelude::*;
use libp2p::{
    mdns, noise,
    request_response::{self, ProtocolSupport},
    swarm::{NetworkBehaviour, SwarmEvent},
    tcp, yamux, StreamProtocol, Swarm,
};
use libp2p_identity::ed25519::Keypair;
use tracing_subscriber::EnvFilter;

// We create a custom network behaviour

#[derive(NetworkBehaviour)]
struct MyBehaviour {
    mdns: mdns::tokio::Behaviour,
    req_res: request_response::cbor::Behaviour<MyRequest, MyResponse>,
}

fn sign(kp: &Keypair, msg: &Vec<u8>) -> String {
    hex::encode(kp.sign(msg))
}

fn mk_swarm(
    kp: &Keypair,
    protocol_support: ProtocolSupport,
) -> Result<Swarm<MyBehaviour>, Box<dyn Error>> {
    let swarm = libp2p::SwarmBuilder::with_existing_identity(kp.clone().into())
        .with_tokio()
        .with_tcp(
            tcp::Config::default(),
            noise::Config::new,
            yamux::Config::default,
        )?
        .with_behaviour(|key| {
            let mdns =
                mdns::tokio::Behaviour::new(mdns::Config::default(), key.public().to_peer_id())?;
            let protocol = [(StreamProtocol::new("/sign-me/1"), protocol_support)];
            let config = request_response::Config::default();
            let req_res =
                request_response::cbor::Behaviour::<MyRequest, MyResponse>::new(protocol, config);
            Ok(MyBehaviour { req_res, mdns })
        })?
        .with_swarm_config(|cfg| cfg.with_idle_connection_timeout(Duration::from_secs(u64::MAX)))
        .build();
    Ok(swarm)
}

#[tokio::main]
pub async fn main() -> Result<(), Box<dyn Error>> {
    let body: Vec<u8> = vec![0, 0, 0, 0, 0, 0, 0, 0];

    let _ = tracing_subscriber::fmt()
        .with_env_filter(EnvFilter::from_default_env())
        .try_init();

    let keypair = libp2p_identity::ed25519::Keypair::generate();
    let key = keypair.public().to_bytes();

    let is_client = match std::env::args().nth(1) {
        Some(arg) => {
            println!("Arg {}", arg);
            true
        }
        _ => false,
    };

    let protocol_support = if is_client {
        ProtocolSupport::Outbound
    } else {
        ProtocolSupport::Inbound
    };
    let mut swarm = mk_swarm(&keypair, protocol_support)?;
    // Tell the swarm to listen on all interfaces and a random, OS-assigned
    // port.
    swarm.listen_on("/ip4/192.168.1.51/tcp/0".parse()?)?;
    println!("ORISIG : {}", sign(&keypair, &body));

    loop {
        match swarm.select_next_some().await {
            SwarmEvent::Behaviour(MyBehaviourEvent::Mdns(mdns::Event::Discovered(list))) => {
                for (peer_id, multiaddr) in list {
                    println!("add peer {:?}, {:?}", peer_id, multiaddr.clone());
                    if is_client {
                        let _ = swarm.dial(multiaddr);
                    }
                }
            }
            SwarmEvent::Behaviour(MyBehaviourEvent::Mdns(mdns::Event::Expired(list))) => {
                for (peer_id, _multiaddr) in list {
                    println!("mDNS discover peer has expired: {peer_id}");
                    // swarm.behaviour_mut().gossipsub.remove_explicit_peer(&peer_id);
                }
            }
            SwarmEvent::Behaviour(MyBehaviourEvent::ReqRes(request_response::Event::Message {
                peer: _peer,
                message:
                    libp2p::request_response::Message::Request {
                        request, channel, ..
                    },
            })) => {
                // println!("Req : {:?} {:?} {:?}", peer, channel, hex::encode(request.body.clone()), );
                println!("REQSIG : {}", hex::encode(request.sig.clone()),);
                let _ = swarm.behaviour_mut().req_res.send_response(
                    channel,
                    MyResponse {
                        sig: keypair.sign(&request.body),
                    },
                );
            }
            SwarmEvent::Behaviour(MyBehaviourEvent::ReqRes(request_response::Event::Message {
                peer: _peer,
                message: libp2p::request_response::Message::Response { response, .. },
            })) => {
                // println!("response : {:?} {:?} {:?}", peer, request_id, "" );
                println!("RESSIG : {}", hex::encode(response.sig.clone()),);
            }
            SwarmEvent::ConnectionEstablished { peer_id, .. } => {
                //connection_id, endpoint, num_established, concurrent_dial_errors, established_in } => {
                println!("ConnectionEstablisted {}", peer_id);
                if is_client {
                    swarm.behaviour_mut().req_res.send_request(
                        &peer_id,
                        MyRequest {
                            key: key.clone(),
                            body: body.clone(),
                            sig: keypair.sign(&body),
                        },
                    );
                }
            }
            e => {
                println!("OTHER {:?}", e)
            }
        }
    }
}