1 files changed, 78 insertions, 0 deletions
diff --git a/games/rstnode/rst-core/src/mailbox.rs b/games/rstnode/rst-core/src/mailbox.rs
new file mode 100644
index 000000000000..c7e4512dbeae
--- /dev/null
+++ b/games/rstnode/rst-core/src/mailbox.rs
@@ -0,0 +1,78 @@
+use crate::wire::{
+    game::{Action, Update},
+    Lobby,
+};
+
+use async_std::sync::RwLock;
+use std::collections::VecDeque;
+
+pub enum ClientUpdate {
+    /// Change to the lobby state
+    Lobby(Lobby),
+    /// A game simulation update
+    GameUpdate(Update),
+}
+
+impl<'l> From<&'l Lobby> for ClientUpdate {
+    fn from(l: &'l Lobby) -> Self {
+        ClientUpdate::Lobby(l.clone())
+    }
+}
+
+impl<'l> From<&'l Update> for ClientUpdate {
+    fn from(u: &'l Update) -> Self {
+        ClientUpdate::GameUpdate(u.clone())
+    }
+}
+
+/// A message out buffer that can be attached to any server entity
+pub struct Outbox {
+    queue: RwLock<VecDeque<ClientUpdate>>,
+}
+
+impl Outbox {
+    pub fn new() -> Self {
+        Self {
+            queue: Default::default(),
+        }
+    }
+
+    /// Queue a new item to send out
+    pub async fn queue(&self, update: impl Into<ClientUpdate>) {
+        let mut q = self.queue.write().await;
+        q.push_back(update.into());
+    }
+
+    /// Run a closure for all queued items
+    pub async fn run_for<F: Fn(&ClientUpdate)>(&self, handle: F) {
+        let q = self.queue.read().await;
+        q.iter().for_each(|item| handle(item));
+    }
+
+    /// Clear the outbox for the next update interval
+    pub async fn clear(&self) {
+        self.queue.write().await.clear();
+    }
+}
+
+pub struct Inbox {
+    queue: RwLock<VecDeque<Action>>,
+}
+
+impl Inbox {
+    pub fn new() -> Self {
+        Self {
+            queue: Default::default(),
+        }
+    }
+
+    /// Queue a new item to send out
+    pub async fn queue(&self, update: impl Into<Action>) {
+        let mut q = self.queue.write().await;
+        q.push_back(update.into());
+    }
+
+    pub async fn pop(&self) -> Option<Action> {
+        self.queue.write().await.pop_front()
+    }
+}