use futures_util::TryStreamExt;
use http_body_util::Empty;
use hyper::header::{
    CONNECTION, SEC_WEBSOCKET_ACCEPT, SEC_WEBSOCKET_KEY, SEC_WEBSOCKET_VERSION, UPGRADE,
};
use hyper::http::HeaderValue;
use hyper::upgrade::Upgraded;
use hyper::{body::Bytes, Request, Response};
use hyper::{Method, StatusCode, Version};
use std::convert::Infallible;

use tokio_tungstenite::tungstenite::handshake::derive_accept_key;
use tokio_tungstenite::tungstenite::protocol::Role;
use tokio_tungstenite::tungstenite::Message;
use tokio_tungstenite::WebSocketStream;

use futures_util::sink::SinkExt;
use futures_util::stream::StreamExt;

async fn handle_connection(ws_stream: WebSocketStream<Upgraded>) {
    tracing::info!("WebSocket connection established");

    let (mut outgoing, incoming) = ws_stream.split();

    let broadcast_incoming = incoming.try_for_each(|msg| {
        tracing::info!("Received a message: {}", msg.to_text().unwrap());

        async { Ok(()) }
    });

    outgoing.send(Message::Text("adsads".into())).await.unwrap();

    match broadcast_incoming.await {
        Ok(_) => tracing::info!("Disconnected"),
        Err(e) => tracing::warn!("Socket failed: {}", e),
    }
}

pub async fn handle_request(
    mut req: Request<hyper::body::Incoming>,
) -> std::result::Result<Response<Empty<Bytes>>, Infallible> {
    dbg!(&req);
    println!("Received a new, potentially ws handshake");
    println!("The request's path is: {}", req.uri().path());
    println!("The request's headers are:");
    for (ref header, _value) in req.headers() {
        println!("* {}", header);
    }
    let upgrade = HeaderValue::from_static("Upgrade");
    let websocket = HeaderValue::from_static("websocket");
    let headers = req.headers();
    let key = headers.get(SEC_WEBSOCKET_KEY);
    let derived = key.map(|k| derive_accept_key(k.as_bytes()));
    if req.method() != Method::GET
        || req.version() < Version::HTTP_11
        || !headers
            .get(CONNECTION)
            .and_then(|h| h.to_str().ok())
            .map(|h| {
                h.split(|c| c == ' ' || c == ',')
                    .any(|p| p.eq_ignore_ascii_case(upgrade.to_str().unwrap()))
            })
            .unwrap_or(false)
        || !headers
            .get(UPGRADE)
            .and_then(|h| h.to_str().ok())
            .map(|h| h.eq_ignore_ascii_case("websocket"))
            .unwrap_or(false)
        || !headers
            .get(SEC_WEBSOCKET_VERSION)
            .map(|h| h == "13")
            .unwrap_or(false)
        || key.is_none()
        || req.uri() != "/socket"
    {
        dbg!();
        let mut resp = Response::new(Empty::new());
        *resp.status_mut() = StatusCode::BAD_REQUEST;
        return Ok(resp);
    }
    let ver = req.version();

    tokio::task::spawn(async move {
        match hyper::upgrade::on(&mut req).await {
            Ok(upgraded) => {
                handle_connection(
                    WebSocketStream::from_raw_socket(upgraded, Role::Server, None).await,
                )
                .await;
            }
            Err(e) => println!("upgrade error: {}", e),
        }
    });
    let mut res = Response::new(Empty::new());
    *res.status_mut() = StatusCode::SWITCHING_PROTOCOLS;
    *res.version_mut() = ver;
    res.headers_mut().append(CONNECTION, upgrade);
    res.headers_mut().append(UPGRADE, websocket);
    res.headers_mut()
        .append(SEC_WEBSOCKET_ACCEPT, derived.unwrap().parse().unwrap());
    Ok(res)
}