sounds

js/event_bus.js

@@ -0,0 +1,52 @@
+"use strict";
+
+class TarinaiEventBus {
+  constructor({ historyLimit = 180 } = {}) {
+    this.handlers = new Map();
+    this.history = [];
+    this.historyLimit = historyLimit;
+  }
+
+  on(type, handler) {
+    if (!type || typeof handler !== "function") return () => {};
+    let list = this.handlers.get(type);
+    if (!list) {
+      list = new Set();
+      this.handlers.set(type, list);
+    }
+    list.add(handler);
+    return () => this.off(type, handler);
+  }
+
+  off(type, handler) {
+    const list = this.handlers.get(type);
+    if (!list) return;
+    list.delete(handler);
+    if (!list.size) this.handlers.delete(type);
+  }
+
+  emit(type, detail = {}) {
+    if (!type) return null;
+    const event = { type, detail: detail || {}, at: performance?.now?.() ?? Date.now() };
+    this.history.unshift(event);
+    if (this.history.length > this.historyLimit) this.history.length = this.historyLimit;
+    const direct = this.handlers.get(type);
+    if (direct) for (const handler of [...direct]) this.safeCall(handler, event);
+    const wildcard = this.handlers.get("*");
+    if (wildcard) for (const handler of [...wildcard]) this.safeCall(handler, event);
+    return event;
+  }
+
+  safeCall(handler, event) {
+    try { handler(event); }
+    catch (err) { console.error("event handler failed", event.type, err); }
+  }
+
+  recent(filter = null, limit = 40) {
+    const list = filter ? this.history.filter(ev => ev.type === filter) : this.history;
+    return list.slice(0, limit);
+  }
+}
+
+window.TarinaiEventBus = TarinaiEventBus;
+window.TarinaiEvents = window.TarinaiEvents || new TarinaiEventBus();