use tokio::{
    io::{AsyncBufReadExt, AsyncWriteExt, BufReader},
    net::TcpListener,
};

#[tokio::main]
async fn main() {
    // Set up a TCP listenner to listen for incoming tcp requests
    let listener = TcpListener::bind("127.0.0.1:8080").await.unwrap();

    // First loop accept all the tcp client requests
    loop {
        // accept the requests
        let (mut socket, _addr) = listener.accept().await.unwrap();

        tokio::spawn(async move {
            // Splitting the TCP socket into read/write halves
            let (reader, mut writer) = socket.split();

            let mut buffer_reader = BufReader::new(reader);

            let mut line: String = String::new();

            // second loop keeps receving input from that one client going
            loop {
                // number of bytes read. We will truncate the buffer
                let bytes_read = buffer_reader.read_line(&mut line).await.unwrap();

                // If we received no bytes then the tcp socket must have closed
                if bytes_read == 0 {
                    break;
                }

                // Does not write to every single tcp sockets that are connected
                // It only writes every single bytes in the input buffer
                writer.write_all(line.as_bytes()).await.unwrap();

                // clear the input buffer
                line.clear();
            }
        });
    }
}