1 files changed, 161 insertions, 0 deletions
diff --git a/planetwars-cli/src/match_runner/match_context.rs b/planetwars-cli/src/match_runner/match_context.rs
new file mode 100644
index 0000000..466da13
--- /dev/null
+++ b/planetwars-cli/src/match_runner/match_context.rs
@@ -0,0 +1,161 @@
+use futures::task::{Context, Poll};
+use futures::{future::Future, task::AtomicWaker};
+use serde::{Deserialize, Serialize};
+use std::fs::File;
+use std::io::Write;
+use std::pin::Pin;
+use std::time::Duration;
+use std::{
+    collections::HashMap,
+    sync::{Arc, Mutex},
+};
+
+#[derive(Serialize, Deserialize, Debug)]
+pub struct RequestMessage {
+    pub request_id: u32,
+    pub timeout: Duration,
+    pub content: Vec<u8>,
+}
+
+pub struct MatchCtx {
+    event_bus: Arc<Mutex<EventBus>>,
+    players: HashMap<u32, PlayerData>,
+    // output: MsgStreamHandle<String>,
+    log_sink: File,
+}
+
+impl MatchCtx {
+    pub fn new(
+        event_bus: Arc<Mutex<EventBus>>,
+        players: HashMap<u32, Box<dyn PlayerHandle>>,
+        log_file: File,
+        // log: MsgStreamHandle<String>,
+    ) -> Self {
+        MatchCtx {
+            event_bus,
+            players: players
+                .into_iter()
+                .map(|(id, handle)| {
+                    let player_handle = PlayerData {
+                        request_ctr: 0,
+                        handle,
+                    };
+                    (id, player_handle)
+                })
+                .collect(),
+            log_sink: log_file,
+        }
+    }
+
+    // TODO: implement a clean way to handle the player not existing
+    pub fn request(&mut self, player_id: u32, content: Vec<u8>, timeout: Duration) -> Request {
+        let player = self.players.get_mut(&player_id).unwrap();
+        let request_id = player.request_ctr;
+        player.request_ctr += 1;
+
+        player.handle.send_request(RequestMessage {
+            request_id,
+            content,
+            timeout,
+        });
+
+        return Request {
+            player_id,
+            request_id,
+            event_bus: self.event_bus.clone(),
+        };
+    }
+
+    pub fn send_info(&mut self, player_id: u32, msg: String) {
+        let player = self.players.get_mut(&player_id).unwrap();
+        player.handle.send_info(msg);
+    }
+
+    pub fn players(&self) -> Vec<u32> {
+        self.players.keys().cloned().collect()
+    }
+
+    // this method should be used to emit log states etc.
+    pub fn log_string(&mut self, message: String) {
+        write!(self.log_sink, "{}\n", message).expect("failed to write to log file");
+    }
+}
+
+pub trait PlayerHandle: Send {
+    fn send_request(&mut self, r: RequestMessage);
+    fn send_info(&mut self, msg: String);
+}
+
+struct PlayerData {
+    request_ctr: u32,
+    handle: Box<dyn PlayerHandle>,
+}
+
+type RequestId = (u32, u32);
+pub struct EventBus {
+    request_responses: HashMap<RequestId, RequestResult<Vec<u8>>>,
+    wakers: HashMap<RequestId, AtomicWaker>,
+}
+
+impl EventBus {
+    pub fn new() -> Self {
+        EventBus {
+            request_responses: HashMap::new(),
+            wakers: HashMap::new(),
+        }
+    }
+}
+
+impl EventBus {
+    pub fn resolve_request(&mut self, id: RequestId, result: RequestResult<Vec<u8>>) {
+        if self.request_responses.contains_key(&id) {
+            // request already resolved
+            // TODO: maybe report this?
+            return;
+        }
+        self.request_responses.insert(id, result);
+        if let Some(waker) = self.wakers.remove(&id) {
+            waker.wake();
+        }
+    }
+}
+
+pub struct Request {
+    player_id: u32,
+    request_id: u32,
+    event_bus: Arc<Mutex<EventBus>>,
+}
+
+impl Request {
+    #[allow(dead_code)]
+    pub fn player_id(&self) -> u32 {
+        self.player_id
+    }
+}
+
+impl Future for Request {
+    type Output = RequestResult<Vec<u8>>;
+
+    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let mut event_bus = self.event_bus.lock().unwrap();
+        let request_id = (self.player_id, self.request_id);
+
+        if let Some(result) = event_bus.request_responses.get(&request_id) {
+            return Poll::Ready(result.clone());
+        }
+
+        event_bus
+            .wakers
+            .entry(request_id)
+            .or_insert_with(|| AtomicWaker::new())
+            .register(cx.waker());
+        return Poll::Pending;
+    }
+}
+
+#[derive(Debug, Clone)]
+pub enum RequestError {
+    Timeout,
+}
+
+pub type RequestResult<T> = Result<T, RequestError>;