use std::os::unix::{io::AsRawFd, net::UnixStream as OsUnixStream, prelude::FromRawFd};

use tempdir::TempDir;

use tokio::{
    io::{AsyncReadExt, AsyncWriteExt},
    net::{UnixListener, UnixStream},
};

use async_send_fd::{AsyncRecvFd, AsyncRecvTokioStream, AsyncSendFd, AsyncSendTokioStream};

const SOCKET_NAME: &str = "tokio_send_fd_test.sock";

#[tokio::test]
async fn send_raw_fd_test() {
    let tmp_dir = TempDir::new("tokio-send-fd").unwrap();

    let sock_path = tmp_dir.path().join(SOCKET_NAME);
    let sock_path1 = sock_path.clone();
    let sock_path2 = sock_path.clone();

    println!("Start listening at: {:?}", sock_path1);
    let listener = UnixListener::bind(sock_path1).unwrap();

    let j1 = tokio::spawn(async move {
        let (stream, _) = listener.accept().await.unwrap();

        println!("Incoming peer connection");
        let (left, right) = OsUnixStream::pair().unwrap();

        println!("Sending peer fd");
        stream.send_fd(left.as_raw_fd()).await.unwrap();
        println!("Succesfullt sent peer fd");

        right.set_nonblocking(true).unwrap();
        let mut peer_stream = UnixStream::from_std(right).unwrap();
        let mut buffer = [0u8; 4];

        println!("Reading data from the peer");
        assert!(peer_stream.read(&mut buffer).await.unwrap() == 4);

        println!("Message sent through a socket: {:?}", buffer);
    });

    let j2 = tokio::spawn(async move {
        println!("Connection to the sender");
        let stream = UnixStream::connect(sock_path2).await.unwrap();

        println!("Succesfully connected to the sender. Reading file descriptor");
        let fd = stream.recv_fd().await.unwrap();
        println!("Succesfully read file descriptor");

        let os_stream = unsafe { OsUnixStream::from_raw_fd(fd) };
        // XXX: Don't forget to make this non-blocking. This gonna save you several days of debugging
        os_stream.set_nonblocking(true).unwrap();

        let mut peer_stream = UnixStream::from_std(os_stream).unwrap();

        println!("Sending data to the peer");
        let buffer: [u8; 4] = [0, 0, 0, 42];
        peer_stream.write(&buffer).await.unwrap();
        println!("Succesfully sent data to the peer");
    });

    tokio::try_join!(j1, j2).unwrap();

    let _ = std::fs::remove_dir(sock_path);
}

#[tokio::test]
async fn send_tokio_stream_test() {
    let tmp_dir = TempDir::new("tokio-send-fd").unwrap();

    let sock_path = tmp_dir.path().join(SOCKET_NAME);
    let sock_path1 = sock_path.clone();
    let sock_path2 = sock_path.clone();

    println!("Start listening at: {:?}", sock_path1);
    let listener = UnixListener::bind(sock_path1).unwrap();

    let j1 = tokio::spawn(async move {
        let (stream, _) = listener.accept().await.unwrap();

        println!("Incoming peer connection");
        let (left, mut right) = UnixStream::pair().unwrap();

        println!("Sending peer fd");
        stream.send_stream(left).await.unwrap();
        println!("Succesfullt sent peer fd");

        let mut buffer = [0u8; 4];

        println!("Reading data from the peer");
        assert!(right.read(&mut buffer).await.unwrap() == 4);

        println!("Message sent through a socket: {:?}", buffer);
    });

    let j2 = tokio::spawn(async move {
        println!("Connection to the sender");
        let stream = UnixStream::connect(sock_path2).await.unwrap();

        println!("Succesfully connected to the sender. Reading file descriptor");
        let mut peer_stream = stream.recv_stream().await.unwrap();

        println!("Sending data to the peer");
        let buffer: [u8; 4] = [0, 0, 0, 42];
        peer_stream.write(&buffer).await.unwrap();
        println!("Succesfully sent data to the peer");
    });

    tokio::try_join!(j1, j2).unwrap();

    let _ = std::fs::remove_dir(sock_path);
}

#[tokio::test]
async fn tokio_halves_test() {
    let tmp_dir = TempDir::new("tokio-send-fd").unwrap();

    let sock_path = tmp_dir.path().join(SOCKET_NAME);
    let sock_path1 = sock_path.clone();
    let sock_path2 = sock_path.clone();

    println!("Start listening at: {:?}", sock_path1);
    let listener = UnixListener::bind(sock_path1).unwrap();

    let j1 = tokio::spawn(async move {
        let (stream, _) = listener.accept().await.unwrap();

        println!("Incoming peer connection");
        let (left, right) = OsUnixStream::pair().unwrap();

        let (_, sender) = stream.into_split();
        println!("Sending peer fd");
        sender.send_fd(left.as_raw_fd()).await.unwrap();
        println!("Succesfullt sent peer fd");

        right.set_nonblocking(true).unwrap();
        let mut peer_stream = UnixStream::from_std(right).unwrap();
        let mut buffer = [0u8; 4];

        println!("Reading data from the peer");
        assert!(peer_stream.read(&mut buffer).await.unwrap() == 4);

        println!("Message sent through a socket: {:?}", buffer);
    });

    let j2 = tokio::spawn(async move {
        println!("Connection to the sender");
        let stream = UnixStream::connect(sock_path2).await.unwrap();

        let (receiver, _) = stream.into_split();
        println!("Succesfully connected to the sender. Reading file descriptor");
        let fd = receiver.recv_fd().await.unwrap();
        println!("Succesfully read file descriptor");

        let os_stream = unsafe { OsUnixStream::from_raw_fd(fd) };
        // XXX: Don't forget to make this non-blocking. This gonna save you several days of debugging
        os_stream.set_nonblocking(true).unwrap();

        let mut peer_stream = UnixStream::from_std(os_stream).unwrap();

        println!("Sending data to the peer");
        let buffer: [u8; 4] = [0, 0, 0, 42];
        peer_stream.write(&buffer).await.unwrap();
        println!("Succesfully sent data to the peer");
    });

    tokio::try_join!(j1, j2).unwrap();

    let _ = std::fs::remove_dir(sock_path);
}