track how many sounds are playing in a channel

src/event_handlers.rs

@@ -0,0 +1,40 @@
+use serenity::async_trait;
+use serenity::model::id::GuildId;
+use songbird::Event;
+use songbird::EventContext;
+use songbird::EventHandler as SongbirdEventHandler;
+use std::collections::HashMap;
+use std::sync::Arc;
+use tokio::sync::RwLock;
+
+pub struct RestartTrack;
+
+#[async_trait]
+impl SongbirdEventHandler for RestartTrack {
+    async fn act(&self, ctx: &EventContext<'_>) -> Option<Event> {
+        if let EventContext::Track(&[(_state, track)]) = ctx {
+            let _ = track.seek_time(Default::default());
+        }
+
+        None
+    }
+}
+
+pub struct UpdateTrackCount {
+    pub guild_id: GuildId,
+    pub track_count: Arc<RwLock<HashMap<GuildId, u32>>>,
+}
+
+#[async_trait]
+impl SongbirdEventHandler for UpdateTrackCount {
+    async fn act(&self, _ctx: &EventContext<'_>) -> Option<Event> {
+        {
+            let mut write_lock = self.track_count.write().await;
+
+            let current = write_lock.get(&self.guild_id).cloned();
+            write_lock.insert(self.guild_id, current.unwrap_or(1) - 1);
+        }
+
+        None
+    }
+}