1 files changed, 37 insertions, 0 deletions
diff --git a/azalea-client/src/plugins/pong.rs b/azalea-client/src/plugins/pong.rs
new file mode 100644
index 00000000..827ddfb1
--- /dev/null
+++ b/azalea-client/src/plugins/pong.rs
@@ -0,0 +1,37 @@
+use bevy_app::{App, Plugin};
+use bevy_ecs::prelude::*;
+
+use super::packet::{
+    config::{ConfigPingEvent, SendConfigPacketEvent},
+    game::PingEvent,
+};
+use crate::packet::game::SendPacketEvent;
+
+/// A plugin that replies to [`ClientboundPing`] packets with
+/// [`ServerboundPong`].
+///
+/// This works in both the `game` and `config` states.
+///
+/// [`ClientboundPing`]: azalea_protocol::packets::game::ClientboundPing
+/// [`ServerboundPong`]: azalea_protocol::packets::game::ServerboundPong
+pub struct PongPlugin;
+impl Plugin for PongPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_observer(reply_to_game_ping)
+            .add_observer(reply_to_config_ping);
+    }
+}
+
+pub fn reply_to_game_ping(trigger: Trigger<PingEvent>, mut commands: Commands) {
+    commands.trigger(SendPacketEvent::new(
+        trigger.entity(),
+        azalea_protocol::packets::game::ServerboundPong { id: trigger.0.id },
+    ));
+}
+
+pub fn reply_to_config_ping(trigger: Trigger<ConfigPingEvent>, mut commands: Commands) {
+    commands.trigger(SendConfigPacketEvent::new(
+        trigger.entity(),
+        azalea_protocol::packets::config::ServerboundPong { id: trigger.0.id },
+    ));
+}