Merge remote-tracking branch 'origin/master'

14 files changed, 1265 insertions, 0 deletions

diff --git a/webhogg/game_server/Cargo.toml b/webhogg/game_server/Cargo.toml
new file mode 100644
index 0000000..bc14942
--- /dev/null
+++ b/webhogg/game_server/Cargo.toml
@@ -0,0 +1,14 @@
+[package]
+name = "game-server"
+version = "0.1.0"
+authors = ["natrixaeria", "truedoctor"]
+edition = "2018"
+description = "A general game server for connections to web clients. Currently (on the way to) deploying a skribbl.io like game."
+
+[dependencies]
+log = "0.4"
+fern = "0.5.8"
+colored = "1.8"
+reqwest = "0.9"
+websocket = "0.22"
+hyper = "0.10"
diff --git a/webhogg/game_server/src/backend_connection.rs b/webhogg/game_server/src/backend_connection.rs
new file mode 100644
index 0000000..a751b30
--- /dev/null
+++ b/webhogg/game_server/src/backend_connection.rs
@@ -0,0 +1,90 @@
+use reqwest::{Response, Client, Url, UrlError, Error as ReqError};
+use std::sync::mpsc::{Sender, Receiver};
+use std::sync::mpsc;
+use crate::server::{UserId, Token};
+use crate::group::GroupId;
+
+pub struct BackendConnection {
+    host: String,
+    req_sender: Sender<RequestData>,
+    res_rec: Receiver<ResponseResult>,
+    max_uid: u32,
+}
+
+#[derive(Debug)]
+pub enum BackendError {
+    UrlError(UrlError),
+    RequestError(ReqError),
+    InvalidTokenFormat,
+    InvalidToken,
+    BadResponse(Response),
+}
+
+pub type TokenValidity = Result<TokenResponse, BackendError>;
+pub type RequestData = Url;
+pub type ResponseResult = Result<Response, ReqError>;
+
+pub struct TokenResponse {
+    pub group_id: GroupId,
+    pub group_type: String,
+    pub group_name: String,
+    pub user_id: UserId,
+}
+
+impl BackendConnection {
+    fn run_background(req_rec: Receiver<RequestData>, res_sender: Sender<ResponseResult>) {
+        let client = Client::new();
+        loop {
+            let request_data = req_rec.recv().unwrap();
+            let location = request_data;
+            let request = client.get(location);
+            let response = request.send();
+            res_sender.send(response).unwrap();
+        }
+    }
+
+    pub fn new(host: &str) -> Self {
+        let (req_sender, req_rec): (Sender<RequestData>, Receiver<RequestData>)
+                                    = mpsc::channel();
+        let (res_sender, res_rec): (Sender<ResponseResult>, Receiver<ResponseResult>)
+                                    = mpsc::channel();
+        std::thread::spawn(move || Self::run_background(req_rec, res_sender));
+        BackendConnection {
+            host: host.to_string(),
+            req_sender,
+            res_rec,
+            max_uid: 420,
+        }
+    }
+
+    pub fn request(&self, location: &str) -> Result<(), UrlError> {
+        Ok(self.req_sender.send(Url::parse(&format!("{}{}", self.host, location))?).unwrap())
+    }
+
+    pub fn get_response(&self) -> ResponseResult {
+        self.res_rec.recv().unwrap()
+    }
+    
+    pub fn validate_token(&mut self, token: &Token) -> TokenValidity {
+        let location = format!("/api/lobby/tokens/{}", token);
+        self.request(&location).map_err(|err| BackendError::UrlError(err))?;
+        let response = self.get_response().map_err(|err| BackendError::RequestError(err))?;
+        if response.status().is_success() {
+            // zu Testzwecken werden noch keine JSON-Daten deserialisiert
+            // Dennis Server gibt ja noch nix zurück
+            self.max_uid += 1;
+            Ok(TokenResponse {
+                group_id: 12,
+                group_type: "scribble".to_string(),
+                group_name: "Scribble".to_string(),
+                user_id: self.max_uid - 1,
+            })
+        } else if response.status() == reqwest::StatusCode::NOT_FOUND {
+            Err(BackendError::InvalidToken)
+        } else if response.status().is_client_error() {
+            Err(BackendError::InvalidTokenFormat)
+        } else {
+            Err(BackendError::BadResponse(response))
+        }
+    }
+}
diff --git a/webhogg/game_server/src/collide.rs b/webhogg/game_server/src/collide.rs
new file mode 100644
index 0000000..16b5357
--- /dev/null
+++ b/webhogg/game_server/src/collide.rs
@@ -0,0 +1,238 @@
+use crate::maths::{Vec2, AABox, RBox};
+
+pub trait Collide<Rhs> {
+    fn collides(&self, other: &Rhs) -> bool;
+}
+
+impl Collide<Vec2> for Vec2 {
+    fn collides(&self, other: &Self) -> bool {
+        self == other
+    }
+}
+
+impl Collide<Vec2> for AABox {
+    fn collides(&self, other: &Vec2) -> bool {
+        self.pos < *other && other < &(self.pos + self.size) 
+    }
+}
+
+impl Collide<AABox> for AABox {
+    fn collides(&self, other: &Self) -> bool {
+        self.pos.x < other.pos.x + other.size.x && other.pos.x < self.pos.x + self.size.x
+        && self.pos.y < other.pos.y + other.size.y && other.pos.y < self.pos.y + self.size.y
+    }
+}
+
+impl Collide<Vec2> for RBox {
+    fn collides(&self, other: &Vec2) -> bool {
+        let v1_diff = *other + self.v1 * (-self.v1.scalar(&(*other - self.pos)) / self.v1.distance2());
+        let v2_diff = *other + self.v2 * (-self.v2.scalar(&(*other - self.pos)) / self.v2.distance2());
+
+        let v1_dist = ((v1_diff - self.pos) / self.v2).x;
+        let v2_dist = ((v2_diff - self.pos) / self.v1).x;
+        0.0 <= v1_dist && v2_dist <= 1.0
+        && 0.0 <= v2_dist && v2_dist <= 1.0
+        //v1_diff < self.pos + self.v2 && self.pos < v1_diff
+        //&& v2_diff < self.pos + self.v1 && self.pos < v2_diff
+    }
+}
+
+impl Collide<AABox> for RBox {
+    fn collides(&self, other: &AABox) -> bool {
+        let other_size = other.pos + other.size;
+
+        // project points onto a orthogonal line
+        let v1_diff = other.pos + self.v1 * (-self.v1.scalar(&(other.pos - self.pos)) / self.v1.distance2());
+        let v2_diff = other.pos + self.v2 * (-self.v2.scalar(&other.pos) / self.v2.distance2());
+        let v1_diff_size = other_size + self.v1 * (-self.v1.scalar(&(other_size - self.pos)) / self.v1.distance2());
+        let v2_diff_size = other_size + self.v2 * (-self.v2.scalar(&(other_size - self.pos)) / self.v2.distance2());
+
+        // calculate the distance
+        let v1_dist = ((v1_diff - self.pos) / self.v2);
+        let v2_dist = ((v2_diff - self.pos) / self.v1);
+        let v1_dist_size = ((v1_diff_size - self.pos) / self.v2);
+        let v2_dist_size = ((v2_diff_size - self.pos) / self.v1);
+
+        let v1_dist = if v1_dist.x.is_finite() {v1_dist.x} else {v1_dist.y};
+        let v2_dist = if v2_dist.x.is_finite() {v2_dist.x} else {v2_dist.y};
+        let v1_dist_size = if v1_dist_size.x.is_finite() {v1_dist_size.x} else {v1_dist_size.y};
+        let v2_dist_size = if v2_dist_size.x.is_finite() {v2_dist_size.x} else {v2_dist_size.y};
+
+        let minx = f32::min(self.pos.x, f32::min((self.pos + self.v1).x, (self.pos + self.v2).x));
+        let maxx = f32::max(self.pos.x, f32::max((self.pos + self.v1).x, (self.pos + self.v2).x));
+        let miny = f32::min(self.pos.y, f32::min((self.pos + self.v1).y, (self.pos + self.v2).y));
+        let maxy = f32::max(self.pos.y, f32::max((self.pos + self.v1).y, (self.pos + self.v2).y));
+
+        0.0 <= v1_dist_size && v1_dist <= 1.0
+        && 0.0 <= v2_dist_size && v2_dist <= 1.0
+        && other.pos.x <= maxx && minx <= other.pos.x + other.size.x
+        && other.pos.y <= maxy && miny <= other.pos.y + other.size.y
+    }
+}
+
+impl<S, T: Collide<S>> Collide<S> for Vec<T> {
+    fn collides(&self, other: &S) -> bool {
+        self.iter().any(|x| x.collides(other))
+    }
+}
+
+#[cfg(test)]
+    mod tests {
+        use super::*;
+        
+        #[test]
+        fn test_collide_dot_dot() {
+             let a = Vec2{x: 1.0, y: 7.5};
+             assert!(a.collides(&a));
+        }
+    
+        #[test]
+        fn test_not_collide_dot_dot() {
+             let a = Vec2{x: 1.0, y: 7.5};
+             let b = Vec2{x: 5.0, y: 7.5};
+             assert!(!a.collides(&b));
+        }
+
+        #[test]
+        fn test_collide_aabox_dot() {
+             let a = Vec2{x: 1.0, y: 2.5};
+             let b = Vec2{x: 3.0, y: 7.5};
+             let c = Vec2{x: 1.5, y: 5.0};
+             let aa_box = AABox{pos: a, size: b};
+
+             assert!(aa_box.collides(&c));
+        }
+    
+        #[test]
+        fn test_not_collide_aabox_dot() {
+             let a = Vec2{x: 1.0, y: 7.5};
+             let b = Vec2{x: 3.0, y: 2.5};
+             let c = Vec2{x: 0.5, y: 5.0};
+             let aa_box = AABox{pos: a, size: b};
+
+             assert!(!(aa_box.collides(&c)));
+        }
+        
+        #[test]
+        fn test_collide_aabox_aabox_intersecting() {
+             let a = Vec2{x: 1.0, y: 2.5};
+             let b = Vec2{x: 3.0, y: 2.5};
+             let aa_box = AABox{pos: a, size: b};
+             let a = Vec2{x: 2.0, y: 3.5};
+             let b = Vec2{x: 3.0, y: 7.5};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(aa_box.collides(&bb_box));
+        }
+
+        #[test]
+        fn test_collide_aabox_aabox_crossed() {
+             let a = Vec2{x: 2.0, y: 0.5};
+             let b = Vec2{x: 1.0, y: 7.5};
+             let aa_box = AABox{pos: a, size: b};
+             let a = Vec2{x: 1.0, y: 3.5};
+             let b = Vec2{x: 5.0, y: 4.5};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(aa_box.collides(&bb_box));
+        }
+    
+        #[test]
+        fn test_not_collide_aabox_aabox() {
+             let a = Vec2{x: 1.0, y: 1.0};
+             let b = Vec2{x: 1.0, y: 1.0};
+             let aa_box = AABox{pos: a, size: b};
+             let a = Vec2{x: 3.0, y: 3.5};
+             let b = Vec2{x: 3.0, y: 7.5};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(!(aa_box.collides(&bb_box)));
+        }
+
+        #[test]
+        fn test_collide_Rbox_dot() {
+             let a = Vec2{x: 1.0, y: 1.0};
+             let b = Vec2{x: 1.0, y: 1.0};
+             let c = Vec2{x: 1.0, y: -1.0};
+             let aa_box = RBox{pos: a, v1: b, v2: c};
+
+             let c = Vec2{x: 1.6, y: 0.6};
+
+             assert!(aa_box.collides(&c));
+        }
+    
+        #[test]
+        fn test_not_collide_rbox_dot() {
+             let a = Vec2{x: 1.0, y: 1.0};
+             let b = Vec2{x: 1.0, y: 1.0};
+             let c = Vec2{x: 1.0, y: -1.0};
+             let aa_box = RBox{pos: a, v1: b, v2: c};
+
+             let c = Vec2{x: 1.4, y: 0.4};
+
+             assert!(!(aa_box.collides(&c)));
+        }
+
+        #[test]
+        fn test_collide_rbox_aabox_intersecting() {
+             let a = Vec2{x: 1.0, y: 2.5};
+             let b = Vec2{x: 0.0, y: 2.5};
+             let c = Vec2{x: 3.0, y: 0.5};
+             let aa_box = RBox{pos: a, v1: b, v2: c};
+             let a = Vec2{x: 2.0, y: 3.5};
+             let b = Vec2{x: 3.0, y: 7.5};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(aa_box.collides(&bb_box));
+        }
+
+        #[test]
+        fn test_collide_rbox_aabox_edges_touch() {
+             let a = Vec2{x: 4.0, y: 5.5};
+             let b = Vec2{x: 1.0, y: 7.5};
+             let aa_box = RBox::new(a, b, 3.9);
+             let a = Vec2{x: 0.0, y: 0.5};
+             let b = Vec2{x: 4.0, y: 5.0};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(aa_box.collides(&bb_box));
+        }
+
+        #[test]
+        fn test_collide_rbox_aabox_crossed() {
+             let a = Vec2{x: 2.0, y: 0.5};
+             let b = Vec2{x: 1.0, y: 7.5};
+             let aa_box = RBox::new(a, b, 3.9);
+             let a = Vec2{x: 0.0, y: 4.5};
+             let b = Vec2{x: 15.0, y: 1.5};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(aa_box.collides(&bb_box));
+        }
+    
+        #[test]
+        fn test_not_collide_rbox_aabox_next_to() {
+             let a = Vec2{x: 2.0, y: 0.5};
+             let b = Vec2{x: 1.0, y: 7.5};
+             let aa_box = RBox::new(a, b, 3.9);
+             let a = Vec2{x: 5.0, y: 40.5};
+             let b = Vec2{x: 15.0, y: 1.5};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(!aa_box.collides(&bb_box));
+        }
+    
+        #[test]
+        fn test_not_collide_rbox_aabox() {
+             let a = Vec2{x: 1.0, y: 1.0};
+             let b = Vec2{x: 0.0, y: 1.0};
+             let c = Vec2{x: 1.0, y: 0.0};
+             let aa_box = RBox{pos: a, v1: b, v2: c};
+             let a = Vec2{x: 3.0, y: 3.5};
+             let b = Vec2{x: 3.0, y: 7.5};
+             let bb_box = AABox{pos: a, size: b};
+
+             assert!(!(aa_box.collides(&bb_box)));
+        }
+
+}
diff --git a/webhogg/game_server/src/game_logger.rs b/webhogg/game_server/src/game_logger.rs
new file mode 100644
index 0000000..c51bfc5
--- /dev/null
+++ b/webhogg/game_server/src/game_logger.rs
@@ -0,0 +1,30 @@
+use colored::*;
+
+fn color_level(level: log::Level) -> colored::ColoredString {
+    let text = format!("{: <8}", level);
+    match level {
+        log::Level::Error => text.red().bold(),
+        log::Level::Warn => text.yellow(),
+        log::Level::Info => text.green(),
+        log::Level::Debug => text.cyan(),
+        log::Level::Trace => text.magenta(),
+    }
+}
+
+pub fn init_logger() {
+    fern::Dispatch::new().format(|out, message, record|{
+        out.finish(format_args!(
+                "{} {} > {}",
+                color_level(record.level()),
+                record.target(),
+                message
+                )
+            )
+        })
+        .level(log::LevelFilter::Debug)
+        .level_for("hyper", log::LevelFilter::Off)
+        .level_for("tokio_reactor", log::LevelFilter::Off)
+        .level_for("reqwest", log::LevelFilter::Off)
+        .chain(std::io::stdout())
+        .apply().unwrap();
+}
diff --git a/webhogg/game_server/src/group.rs b/webhogg/game_server/src/group.rs
new file mode 100644
index 0000000..74a04f7
--- /dev/null
+++ b/webhogg/game_server/src/group.rs
@@ -0,0 +1,13 @@
+use crate::server::{UserId, GameClient, GameServerError};
+
+pub type GroupId = u32;
+
+pub trait Group {
+    fn id(&self) -> GroupId;
+    fn group_type(&self) -> String;
+    fn name(&self) -> String;
+
+    fn run(&mut self);
+
+    fn add_client(&mut self, id: UserId, client: GameClient) -> Result<(), GameServerError>;
+}
diff --git a/webhogg/game_server/src/lobby.rs b/webhogg/game_server/src/lobby.rs
new file mode 100644
index 0000000..6d11a5f
--- /dev/null
+++ b/webhogg/game_server/src/lobby.rs
@@ -0,0 +1,63 @@
+use std::collections::HashMap;
+
+use crate::group::{Group, GroupId};
+use crate::scribble_group::ScribbleGroup;
+
+use crate::server::{UserId, GameClient, GameServerError};
+
+pub struct Lobby {
+    groups: HashMap<GroupId, Box<Group>>,
+}
+
+#[allow(dead_code)]
+impl Lobby {
+    pub fn new() -> Self {
+        Self {
+            groups: HashMap::new(),
+        }
+    }
+
+    fn generate_group(group_type: &str, id: GroupId, name: &str) -> Option<Box<Group>> {
+        match group_type {
+            "scribble" => {
+                Some(Box::new(ScribbleGroup::new(id, name.to_string())))
+            },
+            _ => None,
+        }
+    }
+
+    pub fn add_group(&mut self, group: Box<Group>) {
+        self.groups.insert(group.id(), group);
+    }
+
+    pub fn add_client(&mut self, group_type: &str, group_id: GroupId, group_name: &str,
+                   user_id: UserId, client: GameClient) -> Result<(), GameServerError> {
+        if !self.groups.contains_key(&group_id) {
+            let mut group = match Self::generate_group(group_type, group_id, group_name) {
+                    Some(x) => x,
+                    _ => return Err(GameServerError::GroupCreationError(format!("failed to generate '{}' group", group_type))),
+            };
+            group.run();
+            self.groups.insert(group_id, group);
+        }
+        let group = self.groups.get_mut(&group_id).unwrap();
+        group.add_client(user_id, client)
+    }
+
+    pub fn iter<'b>(&'b self) -> GroupIterator<'b> {
+        GroupIterator { groups: self.groups.values() }
+    }
+}
+
+#[allow(dead_code)]
+pub struct GroupIterator<'a> {
+    groups: std::collections::hash_map::Values<'a, GroupId, Box<Group>>
+}
+
+impl<'a> Iterator for GroupIterator<'a> {
+    type Item = &'a Box<Group>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.groups.next()
+    }
+}
diff --git a/webhogg/game_server/src/main.rs b/webhogg/game_server/src/main.rs
new file mode 100644
index 0000000..cfd9787
--- /dev/null
+++ b/webhogg/game_server/src/main.rs
@@ -0,0 +1,23 @@
+mod group;
+mod maths;
+mod scribble_group;
+mod webhogg_group;
+mod webhogg_game;
+mod collide;
+mod lobby;
+mod server;
+mod backend_connection;
+
+mod game_logger;
+
+#[macro_use] extern crate log;
+
+fn main() {
+    game_logger::init_logger();
+
+    let addr = ("0.0.0.0", 5001);
+    info!("create game server on {:?}", addr);
+    let mut gameserver = server::GameServer::new(addr);
+    gameserver.run().unwrap();
+
+}
diff --git a/webhogg/game_server/src/maths.rs b/webhogg/game_server/src/maths.rs
new file mode 100644
index 0000000..b9303af
--- /dev/null
+++ b/webhogg/game_server/src/maths.rs
@@ -0,0 +1,370 @@
+#[derive(Clone, Copy, Debug)]
+pub struct Vec2 {
+    pub x: f32,
+    pub y: f32,
+}
+
+impl std::ops::Add for Vec2 {
+    type Output = Self;
+    fn add(self, other: Self) -> Self {
+        Self {
+            x: self.x + other.x,
+            y: self.y + other.y
+        }
+    }
+}
+
+impl std::ops::AddAssign<Vec2> for Vec2 {
+    fn add_assign(&mut self, other: Vec2) {
+        self.x += other.x;
+        self.y += other.y;
+    }
+}
+
+impl std::ops::Sub for Vec2 {
+    type Output = Self;
+    fn sub(self, other: Self) -> Self {
+        Self {
+            x: self.x - other.x,
+            y: self.y - other.y
+        }
+    }
+}
+
+impl std::ops::SubAssign<Vec2> for Vec2 {
+    fn sub_assign(&mut self, other: Vec2) {
+        self.x -= other.x;
+        self.y -= other.y;
+    }
+}
+
+impl std::ops::Neg for Vec2 {
+    type Output = Self;
+    fn neg(self) -> Self {
+        Self {
+            x: -self.x,
+            y: -self.y
+        }
+    }
+}
+
+impl std::ops::Mul<f32> for Vec2 {
+    type Output = Self;
+    fn mul(self, scale: f32) -> Self {
+        Self {
+            x: self.x * scale,
+            y: self.y * scale
+        }
+    }
+}
+
+impl std::ops::Div<f32> for Vec2 {
+    type Output = Self;
+    fn div(self, scale: f32) -> Self {
+        Self {
+            x: self.x / scale,
+            y: self.y / scale
+        }
+    }
+}
+
+impl std::ops::Div<Vec2> for Vec2 {
+    type Output = Self;
+    fn div(self, scale: Vec2) -> Self {
+        Self {
+            x: self.x / scale.x,
+            y: self.y / scale.y
+        }
+    }
+}
+
+
+impl std::cmp::PartialOrd for Vec2 {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        if self.x <= other.x && self.y <= other.y {
+            Some(std::cmp::Ordering::Less)
+        } else if self.x > other.x && self.y > other.y {
+            Some(std::cmp::Ordering::Greater)
+        } else {
+            None
+        }
+    }
+}
+
+impl std::cmp::PartialEq for Vec2 {
+    fn eq(&self, other: &Self) -> bool {
+        f32::abs(self.x - other.x) < 1e-8
+        && f32::abs(self.y - other.y) < 1e-8
+    }
+}
+
+impl std::cmp::Eq for Vec2 {}
+
+impl Vec2 {
+    pub fn distance(&self) -> f32 {
+        f32::sqrt(self.distance2())
+    }
+
+    pub fn distance2(&self) -> f32 {
+        self.scalar(self)
+    }
+
+    pub fn scalar(&self, other: &Vec2) -> f32 {
+        self.x * other.x + self.y * other.y
+    }
+
+    pub fn norm(&self) -> Vec2 {
+        let len = self.distance();
+        Vec2 {
+            x: self.x / len,
+            y: self.y / len,    
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug)]
+pub struct AABox {
+    pub pos: Vec2,
+    /// the size may not be smaller than zero
+    pub size: Vec2, 
+}
+
+impl std::ops::Add<Vec2> for AABox {
+    type Output = Self;
+    fn add(self, other: Vec2) -> Self {
+        Self {
+            pos: self.pos + other,
+            size: self.size,
+        }
+    }
+}
+
+impl std::ops::AddAssign<Vec2> for AABox {
+    fn add_assign(&mut self, other: Vec2) {
+        self.pos += other
+    }
+}
+
+impl std::ops::Sub<Vec2> for AABox {
+    type Output = Self;
+    fn sub(self, other: Vec2) -> Self {
+        Self {
+            pos: self.pos + other,
+            size: self.size
+        }
+    }
+}
+
+impl std::ops::SubAssign<Vec2> for AABox {
+    fn sub_assign(&mut self, other: Vec2) {
+        self.pos -= other
+    }
+}
+
+impl std::cmp::PartialEq for AABox {
+    fn eq(&self, other: &Self) -> bool {
+        self.pos == other.pos
+            && self.size == other.size
+    }
+}
+
+impl std::cmp::Eq for AABox {}
+
+#[derive(Clone, Copy, Debug)]
+pub struct RBox {
+    /// origin
+    pub pos: Vec2,
+    /// Vwctor1
+    pub v1: Vec2, 
+    /// Vector2
+    pub v2: Vec2,
+}
+
+impl RBox {
+    pub fn new(pos: Vec2, orientation: Vec2, width: f32) -> Self {
+        let scale = width / orientation.distance();
+        let orth = Vec2 {x: orientation.x / scale, y: -orientation.y / scale};
+        Self {
+            pos: pos,
+            v1: orientation,
+            v2: orth,
+        }
+    }
+}   
+
+impl std::ops::Add<Vec2> for RBox {
+    type Output = Self;
+    fn add(self, other: Vec2) -> Self {
+        Self {
+            pos: self.pos + other,
+            v1: self.v1,
+            v2: self.v2,
+        }
+    }
+}
+
+impl std::ops::AddAssign<Vec2> for RBox {
+    fn add_assign(&mut self, other: Vec2) {
+        self.pos += other
+    }
+}
+
+impl std::ops::Sub<Vec2> for RBox {
+    type Output = Self;
+    fn sub(self, other: Vec2) -> Self {
+        Self {
+            pos: self.pos + other,
+            v1: self.v1 + other,
+            v2: self.v2,
+        }
+    }
+}
+
+impl std::ops::SubAssign<Vec2> for RBox {
+    fn sub_assign(&mut self, other: Vec2) {
+        self.pos -= other
+    }
+}
+
+impl std::cmp::PartialEq for RBox {
+    fn eq(&self, other: &Self) -> bool {
+        self.pos == other.pos
+            && self.v1 == other.v1
+            && self.v1 == self.v2
+    }
+}
+
+impl std::cmp::Eq for RBox {}
+
+#[cfg(test)]
+mod tests {
+    // Note this useful idiom: importing names from outer (for mod tests) scope.
+    use super::*;
+
+    #[test]
+    fn test_less_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+
+        assert!(b < a);
+    }
+
+    #[test]
+    fn test_less_vec2_fail() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: 3.0, y: 2.5};
+
+        assert!(!(a < b));
+    }
+
+    #[test]
+    fn test_greater_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+
+        assert!(a > b);
+    }
+
+    #[test]
+    fn test_greater_vec2_fail() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: 3.0, y: 2.5};
+
+        assert!(!(a > b));
+    }
+
+
+    #[test]
+    fn test_add_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+        let c = Vec2{x: -2.0, y: 10.0};
+
+        assert_eq!(a + b, c);
+    }
+
+    #[test]
+    fn test_neg_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -1.0, y: -7.5};
+
+        assert_eq!(-a, b);
+    }
+
+    #[test]
+    fn test_sub_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+        let c = Vec2{x: 4.0, y: 5.0};
+
+        assert_eq!(a - b, c);
+    }
+
+    #[test]
+    fn test_distance_vec2() {
+        let a = Vec2{x: 2.0, y: 2.0};
+
+        assert!(f32::abs(a.distance() - 2.0) < 1e8);
+    }
+
+    #[test]
+    fn test_distance2_vec2() {
+        let a = Vec2{x: 1.0, y: 2.0};
+
+        assert!(f32::abs(a.distance2() - 5.0) < 1e8);
+    }
+
+    #[test]
+    fn test_norm_vec2() {
+        let a = Vec2{x: 2.0, y: -2.0};
+        let b = Vec2{x: std::f32::consts::FRAC_1_SQRT_2, y: -std::f32::consts::FRAC_1_SQRT_2};
+
+        assert_eq!(a.norm(), b);
+    }
+
+    #[test]
+    fn test_add_aabox_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+        let mut aa_box = AABox{pos: a, size: b};
+        let bb_box = AABox{pos: a + b,size: b};
+        aa_box += b;
+
+        assert_eq!(aa_box, bb_box);
+    }
+
+    #[test]
+    fn test_sub_aabox_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+        let mut aa_box = AABox{pos: a, size: b};
+        let bb_box = AABox{pos: a - b,size: b};
+        aa_box -= b;
+
+        assert_eq!(aa_box, bb_box);
+    }
+
+    #[test]
+    fn test_add_rbox_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+        let c = Vec2{x: -3.0, y: 2.5};
+        let mut aa_box = RBox{pos: a, v1: b, v2: c};
+        let bb_box = RBox{pos: a + b, v1: b, v2: c};
+        aa_box += b;
+
+        assert_eq!(aa_box, bb_box);
+    }
+
+    #[test]
+    fn test_sub_rbox_vec2() {
+        let a = Vec2{x: 1.0, y: 7.5};
+        let b = Vec2{x: -3.0, y: 2.5};
+        let c = Vec2{x: -3.0, y: 2.5};
+        let mut aa_box = RBox{pos: a, v1: b, v2: c};
+        let bb_box = RBox{pos: a - b, v1: b, v2: c};
+        aa_box -= b;
+
+        assert_eq!(aa_box, bb_box);
+    }
+}
diff --git a/webhogg/game_server/src/scribble_group.rs b/webhogg/game_server/src/scribble_group.rs
new file mode 100644
index 0000000..8980e7b
--- /dev/null
+++ b/webhogg/game_server/src/scribble_group.rs
@@ -0,0 +1,65 @@
+use crate::group::{Group, GroupId};
+use crate::server::{UserId, GameClient,
+                    ClientSender, ClientReceiver,
+                    GameServerError};
+use std::collections::HashMap;
+use std::sync::{Arc, Mutex};
+
+pub struct ScribbleGroup {
+    id: GroupId,
+    name: String,
+    senders: Arc<Mutex<HashMap<UserId, ClientSender>>>
+}
+
+impl Group for ScribbleGroup {
+    fn id(&self) -> GroupId {
+        self.id
+    }
+
+    fn group_type(&self) -> String {
+        "scribble".to_string()
+    }
+
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    fn run(&mut self) {
+        info!("a new group {}:'{}' runs now", self.id, self.name);
+    }
+
+    fn add_client(&mut self, id: UserId, client: GameClient) -> Result<(), GameServerError> {
+        debug!("user {} joined the group {}:'{}'", id, self.id, self.name);
+        let (sen, rec) = client.split();
+        self.senders.lock().unwrap().insert(id, sen);
+        let senders_mutex = self.senders.clone();
+        let self_uid = id;
+        std::thread::spawn(move || Self::broadcast_clients(self_uid, rec, senders_mutex));
+        Ok(())
+    }
+}
+
+impl ScribbleGroup {
+    pub fn new(id: GroupId, name: String) -> Self {
+        Self { id, name, senders: Arc::new(Mutex::new(HashMap::new())) }
+    }
+
+    fn broadcast_clients(self_uid: UserId, mut rec: ClientReceiver, senders_mutex: Arc<Mutex<HashMap<UserId, ClientSender>>>) {
+        loop {
+            let message = match rec.recv_message() {
+                Ok(x) => x,
+                _ => break
+            };
+            //trace!("got message: '{:?}'", message);
+            let mut senders = senders_mutex.lock().unwrap();
+            for (uid, sender) in senders.iter_mut() {
+                if self_uid != *uid {
+                    sender.send_message(&message)
+                        .unwrap_or_else(|_| debug!("tried to send message to {}, but failed", *uid));
+                }
+            }
+        }
+        senders_mutex.lock().unwrap().remove(&self_uid);
+        info!("client {} has left", self_uid);
+    }
+}
diff --git a/webhogg/game_server/src/server.rs b/webhogg/game_server/src/server.rs
new file mode 100644
index 0000000..5b1a7a9
--- /dev/null
+++ b/webhogg/game_server/src/server.rs
@@ -0,0 +1,198 @@
+use websocket::{OwnedMessage,
+    stream::sync::Splittable,
+    sync::Server,
+    client::sync::Client,
+    server::{NoTlsAcceptor,
+        sync::AcceptResult},
+    receiver, sender};
+use std::net::{SocketAddr, ToSocketAddrs, TcpStream};
+use std::sync::{mpsc,
+                mpsc::{Sender, Receiver}};
+use crate::lobby::Lobby;
+use crate::backend_connection::BackendConnection;
+
+pub type ClientReceiver = receiver::Reader<<TcpStream as Splittable>::Reader>;
+pub type ClientSender = sender::Writer<<TcpStream as Splittable>::Writer>;
+
+const PROTOCOL: &str = "tuesday";
+
+pub type Token = u32;
+pub type UserId = u32;
+
+#[derive(Debug)]
+pub enum GameServerError {
+    BindError(std::io::Error),
+    HandshakeRequestError,
+    InvalidProtocolError,
+    AcceptError(std::io::Error),
+    GroupError(String),
+    GroupCreationError(String),
+}
+
+impl std::fmt::Display for GameServerError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
+        match self {
+            GameServerError::BindError(e) => write!(f, "BindError: {}", e),
+            GameServerError::HandshakeRequestError => write!(f, "HandshakeRequestError"),
+            GameServerError::InvalidProtocolError => write!(f, "InvalidProtocolError"),
+            GameServerError::AcceptError(e) => write!(f, "AcceptError: {}", e),
+            GameServerError::GroupError(e) => write!(f, "GroupError: {}", e),
+            GameServerError::GroupCreationError(e) => write!(f, "GroupCreationError: {}", e),
+        }
+    }
+}
+
+pub struct GameServer {
+    addr: SocketAddr,
+    lobby: Lobby,
+    backend: BackendConnection,
+}
+
+pub struct GameClient {
+    addr: SocketAddr,
+    client: Client<TcpStream>,
+}
+
+impl GameClient {
+    fn from_raw(client: Client<TcpStream>) -> Result<Self, ()> {
+        let addr = client.peer_addr().map_err(|_| ())?;
+        info!("got a client connection from: {}", addr);
+        Ok(GameClient {
+            addr,
+            client,
+        })
+    }
+
+    fn require_token(&mut self) -> Option<Token> {
+        let message = self.client
+                 .recv_message()
+                 .ok()?;
+        if let OwnedMessage::Text(text) = message {
+            text.parse().ok()
+        } else {
+            None
+        }
+    }
+
+    fn host_name(&self) -> SocketAddr {
+        self.addr
+    }
+
+    pub fn split(self) -> (ClientSender, ClientReceiver) {
+        let (rec, sen) = self.client.split().unwrap();
+        (sen, rec)
+    }
+}
+
+type ClientConnection = Result<GameClient, GameServerError>;
+
+impl GameServer {
+    pub fn new<T: ToSocketAddrs>(addr: T) -> Self {
+        let addr = addr.to_socket_addrs().unwrap().next().unwrap();
+        debug!("ws address: {}", addr);
+        info!("create lobby");
+        let lobby = Lobby::new();
+        let backend = BackendConnection::new("https://kobert.dev");
+        info!("got a C# backend connection");
+        GameServer {
+            addr,
+            lobby: lobby,
+            backend: backend,
+        }
+    }
+
+    pub fn run(&mut self) -> Result<(), GameServerError> {
+        let reader = self.read_clients();
+        loop {
+            let connection = reader.recv().unwrap()?;
+            self.add_client(connection);
+        }
+    }
+
+    fn add_client(&mut self, mut client: GameClient) {
+        let token = client.require_token();
+        if let Some(token) = token {
+            let result = self.backend.validate_token(&token);
+            match result {
+                Err(err) => warn!("client's token {} is not valid: '{:?}'",
+                                  token, err),
+                Ok(result) => {
+                    debug!("client validation was successfull");
+                    let user_id = result.user_id;
+                    let group_id = result.group_id;
+                    let group_type = result.group_type;
+                    let group_name = result.group_name;
+                    debug!("add client: (id:{}, token:{}, host:{}) to \"{}\"",
+                        user_id, token, client.host_name(), group_name);
+                    //clients.lock().unwrap().insert(token, client);
+                    self.lobby.add_client(&group_type, group_id,
+                                     &group_name, user_id, client)
+                              .unwrap_or_else(|e| warn!("failed to add client: {}", e));
+                }
+            }
+        } else {
+            warn!("client sent invalid token");
+        }
+    }
+
+    fn read_clients(&self) -> Receiver<ClientConnection> {
+        let (sen, rec): (Sender<ClientConnection>, Receiver<ClientConnection>)
+                     = mpsc::channel();
+        let addr = self.addr;
+        std::thread::spawn(move || {
+            match Self::handle_requests(addr, &sen) {
+                Err(e) => sen.send(Err(e)).unwrap(),
+                _ => (),
+            }
+        });
+        rec
+    }
+
+    fn handle_requests(addr: SocketAddr, sen: &Sender<ClientConnection>) -> Result<(), GameServerError> {
+        let server = match Server::<NoTlsAcceptor>::bind(addr) {
+            Ok(v) => v,
+            Err(e) => {
+                error!("websocket binding error");
+                Err(GameServerError::BindError(e))?
+            },
+        };
+        info!("webserver is being launched");
+        for req in server {
+            sen.send(Ok(Self::handle_request(req)?)).unwrap();
+        }
+        info!("webserver is being shut down");
+        Ok(())
+    }
+
+    fn handle_request(req: AcceptResult<TcpStream>) -> ClientConnection {
+        match req {
+            Ok(req) => {
+                if !req.protocols().contains(&PROTOCOL.to_string()) {
+                    warn!("a client tried to connect without {} protocol", PROTOCOL);
+                    req.reject().unwrap();
+                    Err(GameServerError::InvalidProtocolError)
+                } else {
+                    match req.use_protocol(PROTOCOL).accept() {
+                        Ok(client) => {
+                            match GameClient::from_raw(client) {
+                                Ok(client) => Ok(client),
+                                Err(_) => {
+                                    error!("could not create a client");
+                                    Err(GameServerError::HandshakeRequestError)
+                                }
+                            }
+                        },
+                        Err((_, e)) => {
+                            warn!("client handshake failed");
+                            Err(GameServerError::AcceptError(e))
+                        }
+                    }
+                }
+            },
+            Err(_) => {
+                warn!("invalid client request");
+                Err(GameServerError::HandshakeRequestError)
+            }
+        }
+    }
+}
diff --git a/webhogg/game_server/src/webhogg_game.rs b/webhogg/game_server/src/webhogg_game.rs
new file mode 100644
index 0000000..7b94fcb
--- /dev/null
+++ b/webhogg/game_server/src/webhogg_game.rs
@@ -0,0 +1,13 @@
+use crate::maths::Vec2;
+
+pub struct WebhoggPlayer {
+    pos: Vec2,
+}
+
+pub struct WebhoggGame {
+    player1: WebhoggPlayer,
+    player2: WebhoggPlayer,
+}
+
+impl WebhoggGame {
+}
diff --git a/webhogg/game_server/src/webhogg_group.rs b/webhogg/game_server/src/webhogg_group.rs
new file mode 100644
index 0000000..091f7f8
--- /dev/null
+++ b/webhogg/game_server/src/webhogg_group.rs
@@ -0,0 +1,71 @@
+use crate::group::{Group, GroupId};
+use crate::server::{UserId, GameClient,
+                    ClientSender, ClientReceiver,
+                    GameServerError};
+use std::collections::HashMap;
+use std::sync::{Arc, Mutex};
+
+pub struct WebhoggGroup {
+    id: GroupId,
+    name: String,
+    senders: Arc<Mutex<HashMap<UserId, ClientSender>>>
+}
+
+impl Group for WebhoggGroup {
+    fn id(&self) -> GroupId {
+        self.id
+    }
+
+    fn group_type(&self) -> String {
+        "webhogg".to_string()
+    }
+
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    fn run(&mut self) {
+        info!("a new group {}:'{}' runs now", self.id, self.name);
+    }
+
+    fn add_client(&mut self, id: UserId, client: GameClient) -> Result<(), GameServerError> {
+        if self.senders.lock().unwrap().len() > 1 {
+            return Err(GameServerError::GroupError(
+                    format!("user {} was not able to join the {} group, {}",
+                            "because the client limit has been exceeded",
+                            id, self.name)));
+        } 
+        debug!("user {} joined the group {}:'{}'", id, self.id, self.name);
+        let (sen, rec) = client.split();
+        self.senders.lock().unwrap().insert(id, sen);
+        let senders_mutex = self.senders.clone();
+        let self_uid = id;
+        std::thread::spawn(move || Self::broadcast_clients(self_uid, rec, senders_mutex));
+        Ok(())
+    }
+}
+
+impl WebhoggGroup {
+    pub fn new(id: GroupId, name: String) -> Self {
+        Self { id, name, senders: Arc::new(Mutex::new(HashMap::new())) }
+    }
+
+    fn broadcast_clients(self_uid: UserId, mut rec: ClientReceiver, senders_mutex: Arc<Mutex<HashMap<UserId, ClientSender>>>) {
+        loop {
+            let message = match rec.recv_message() {
+                Ok(x) => x,
+                _ => break
+            };
+            //trace!("got message: '{:?}'", message);
+            let mut senders = senders_mutex.lock().unwrap();
+            for (uid, sender) in senders.iter_mut() {
+                if self_uid != *uid {
+                    sender.send_message(&message)
+                        .unwrap_or_else(|_| debug!("tried to send message to {}, but failed", *uid));
+                }
+            }
+        }
+        senders_mutex.lock().unwrap().remove(&self_uid);
+        info!("client {} has left", self_uid);
+    }
+}
diff --git a/webhogg/game_server/src/webhogg_player.rs b/webhogg/game_server/src/webhogg_player.rs
new file mode 100644
index 0000000..38b9596
--- /dev/null
+++ b/webhogg/game_server/src/webhogg_player.rs
@@ -0,0 +1,3 @@
+pub struct WebhoggPlayer {
+
+}
diff --git a/webhogg/game_server/src/ws_test.html b/webhogg/game_server/src/ws_test.html
new file mode 100644
index 0000000..3b3d4ce
--- /dev/null
+++ b/webhogg/game_server/src/ws_test.html
@@ -0,0 +1,74 @@
+<!doctype html>
+<html>
+    <head>
+        <title>WS Test</title>
+        <style>
+.b {
+    border-bottom: 1px solid black;
+}
+        </style>
+    </head>
+    <body style='background: black; color: white'>
+        <div id='cons'>connected</div><br>
+        <button onclick='test_connection()'>Launch</button><br>
+        <span>Server address: </span><input id='addr'></input>
+        <div align='right'><span>Message</span><input id='msg'></input> <button onclick='send_text()'>Send</button></div>
+        <div id='chat' style='background: rgb(20, 20, 20); padding-left: 20px; margin: 40px' />
+    </body>
+    <script>
+function get_addr() {
+    return document.getElementById('addr').value;
+}
+
+function test_connection() {
+    let a = 'ws://' + get_addr();
+    add_text('create a new connection at "' + a + '"');
+    ws = new WebSocket(a, 'tuesday');
+    ws.addEventListener('open', function (event) {
+        add_text('connection established');
+        toggle_connected(true);
+        // send token
+        ws.send('42');
+    });
+    ws.addEventListener('error', function (event) {
+        add_text('ws error occured: "' + event + '"');
+        toggle_connected(false);
+    });
+    ws.addEventListener('close', function (event) {
+        add_text('ws is closed now');
+        toggle_connected(false);
+    });
+    ws.addEventListener('message', function (event) {
+        add_text('got ws message: "' + event.data + '"');
+    });
+}
+
+function send_text() {
+    let msg = document.getElementById('msg').value;
+    ws.send(msg);
+    add_text('sent message: "' + msg + '"');
+}
+
+function add_text(text, color='white') {
+    let c = document.getElementById('chat');
+    let n = document.createElement('span');
+    n.setAttribute('class', 'b');
+    n.style = 'color: ' + color;
+    n.textContent = (new Date()).toTimeString().substring(0, 8) + '|> '+ text;
+    c.appendChild(n);
+    c.appendChild(document.createElement('br'));
+}
+function toggle_connected(con) {
+    let c = document.getElementById('cons');
+    if (con) {
+        c.style = 'background: green'
+        c.textContent = 'connected';
+    } else {
+        c.style = 'background: red'
+        c.textContent = 'not connected';
+    }
+}
+toggle_connected(false);
+add_text("JS loaded");
+    </script>
+</html>