use std::io::{BufRead, BufReader, Write};
use std::net::TcpStream;
use std::sync::mpsc;
use std::thread;
use std::time::{Duration, Instant};

pub fn connect(addr: &str) -> Result<TcpStream, Box<dyn std::error::Error>> {
    let (tx, rx) = mpsc::channel();
    let addr_str = addr.to_string();
    thread::spawn(move || {
        match TcpStream::connect(&addr_str) {
            Ok(s) => tx.send(Ok(s)).unwrap(),
            Err(e) => tx.send(Err(e)).unwrap(),
        }
    });
    match rx.recv_timeout(Duration::from_secs(3)) {
        Ok(Ok(s)) => {
            let mut ping_writer = s.try_clone().unwrap();
            let mut ping_reader = BufReader::new(s.try_clone().unwrap());
            let start = Instant::now();
            writeln!(ping_writer, "PING").unwrap();
            let mut response = String::new();
            ping_reader.read_line(&mut response).unwrap();
            let elapsed = start.elapsed();
            println!("\n\rConnected to {} with ping delay: {:?}", addr, elapsed);
            Ok(s)
        }
        Ok(Err(e)) => Err(Box::new(e)),
        Err(mpsc::RecvTimeoutError::Timeout) => Err("Connection timed out after 3 seconds".into()),
        Err(_) => Err("Connection attempt failed".into()),
    }
}