use std::env;
use std::net::SocketAddr;

use futures_util::StreamExt;
use tokio::net::{TcpListener, TcpStream};

pub type BoxError = Box<dyn std::error::Error + Send + Sync>;

async fn accept_connection(stream: TcpStream, addr: SocketAddr) -> Result<(), BoxError> {
    println!("Peer address: {}", addr);


    let ws_stream = tokio_tungstenite::accept_async(stream)
        .await
        .err(format!("Error during WS handshake.").into());

    println!("New WebSocket connection: {}", addr);

    let (write, read) = ws_stream.split();
    read.forward(write).await.expect("Failed to forward message")
}

#[tokio::main]
async fn main() -> Result<(), BoxError> {
    // Create the event loop and TCP listener we'll accept connections on.
    let addr = env::args().nth(1).unwrap_or_else(|| "127.0.0.1:8080".to_string());
    let try_socket = TcpListener::bind(&addr).await;
    let mut listener = try_socket.expect("Failed to bind");

    while let Ok((stream, addr)) = listener.accept().await {
        tokio::spawn(accept_connection(stream, addr));
    }

    Ok(())
}