Refactoring, comments & overall improvements

modules/music/events/voice-state-update.ts

@@ -0,0 +1,65 @@
+import { BaseGuildVoiceChannel, User, VoiceState } from "discord.js";
+
+import Client from "$lib/client.js";
+import Music from "$mlib/music.js";
+
+import { asleep } from "../lib/misc.js";
+import replies from "../lib/replies.js";
+
+/** Amount of time Quetza can be alone in voice channel. */
+const TIME_TILL_DISCONNECT = 30_000;
+
+/**
+ * Deduct {@link BaseGuildVoiceChannel} user is a member of.
+ *
+ * @returns BaseGuildVoiceChannel user is a member of, null if not a member of any.
+ *
+ * @param user - User that might be in one of a channels.
+ * @param channels - List of channels that might have user as it member.
+ */
+function resolveVoiceChannel(
+    user: User,
+    ...channels: (BaseGuildVoiceChannel | null)[]
+): BaseGuildVoiceChannel | null {
+    return (
+        channels.find((channel) => channel?.members.some((member) => member.user === user)) ?? null
+    );
+}
+
+/**
+ * Tracks voice channel Quetza is connected to.
+ *
+ * @remark Destroys player if Quetza appears to be alone.
+ *
+ * @param client - Quetza client.
+ * @param eventee - Old and new {@link VoiceState}.
+ * @param controller - Module's controller.
+ */
+async function execute(
+    client: Client<true>,
+    eventee: [VoiceState, VoiceState],
+    controller: Music
+): Promise<void> {
+    const [oldState, newState] = eventee;
+
+    const player = controller.get(oldState.guild);
+
+    const channel = resolveVoiceChannel(client.user, oldState.channel, newState.channel);
+
+    if (!player || !channel) {
+        return;
+    }
+
+    if (channel.members.size === 1) {
+        await asleep(TIME_TILL_DISCONNECT);
+        if (channel.members.size === 1 && channel.members.first()?.user === client.user) {
+            await player.channel.send(replies.alone());
+            player.destroy();
+        }
+    }
+}
+
+/** Event name. */
+const name = "voiceStateUpdate";
+
+export { execute, name };