use tokio::io::copy;
use tokio::net::{TcpListener, TcpStream};

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let listener = TcpListener::bind("0.0.0.0:8000").await?;

    loop {
        let (stream, _addr) = listener.accept().await?;
        // TODO: use a lookup to see where it should be proxied to
        let to_stream = TcpStream::connect("192.168.1.28:6667").await?; // TODO: remove this placeholder

        tokio::spawn(async move {
            proxy(stream, to_stream).await?;

            Ok::<(), anyhow::Error>(())
        });
    }
}

async fn proxy(left: TcpStream, right: TcpStream) -> anyhow::Result<()> {
    let (mut left_read, mut left_write) = left.into_split();
    let (mut right_read, mut right_write) = right.into_split();

    tokio::select! {
        r = copy(&mut left_read, &mut right_write) => r?,
        r = copy(&mut right_read, &mut left_write) => r?
    };

    Ok(())
}