From 4ed6ec7c3df009d9c81d9b3c6422ed1643791699 Mon Sep 17 00:00:00 2001
From: Kieran <kieran@harkin.me>
Date: Tue, 12 Dec 2023 22:47:06 +0000
Subject: [PATCH] feat: use eventemitter3 in ExternalStore

---
 packages/shared/package.json          |  1 +
 packages/shared/src/external-store.ts | 28 +++++++++------------------
 yarn.lock                             |  1 +
 3 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/packages/shared/package.json b/packages/shared/package.json
index 02e4978b8..6f054de5b 100644
--- a/packages/shared/package.json
+++ b/packages/shared/package.json
@@ -16,6 +16,7 @@
     "@noble/hashes": "^1.3.2",
     "@scure/base": "^1.1.2",
     "debug": "^4.3.4",
+    "eventemitter3": "^5.0.1",
     "light-bolt11-decoder": "^3.0.0"
   },
   "devDependencies": {
diff --git a/packages/shared/src/external-store.ts b/packages/shared/src/external-store.ts
index 21d3f0354..00f0ea722 100644
--- a/packages/shared/src/external-store.ts
+++ b/packages/shared/src/external-store.ts
@@ -1,27 +1,19 @@
-export type HookFn<TSnapshot> = (e?: TSnapshot) => void;
+import EventEmitter from "eventemitter3";
 
-export interface HookFilter<TSnapshot> {
-  fn: HookFn<TSnapshot>;
+interface ExternalStoreEvents {
+  change: () => void;
 }
 
 /**
- * Simple React hookable store with manual change notifications
+ * Simple hookable store with manual change notifications
  */
-export abstract class ExternalStore<TSnapshot> {
-  #hooks: Array<HookFilter<TSnapshot>> = [];
+export abstract class ExternalStore<TSnapshot> extends EventEmitter<ExternalStoreEvents> {
   #snapshot: TSnapshot = {} as TSnapshot;
   #changed = true;
 
-  hook(fn: HookFn<TSnapshot>) {
-    this.#hooks.push({
-      fn,
-    });
-    return () => {
-      const idx = this.#hooks.findIndex(a => a.fn === fn);
-      if (idx >= 0) {
-        this.#hooks.splice(idx, 1);
-      }
-    };
+  hook(cb: () => void) {
+    this.on("change", cb);
+    return () => this.off("change", cb);
   }
 
   snapshot(p?: any) {
@@ -34,9 +26,7 @@ export abstract class ExternalStore<TSnapshot> {
 
   protected notifyChange(sn?: TSnapshot) {
     this.#changed = true;
-    if (this.#hooks.length > 0) {
-      this.#hooks.forEach(h => h.fn(sn));
-    }
+    this.emit("change");
   }
 
   abstract takeSnapshot(p?: any): TSnapshot;
diff --git a/yarn.lock b/yarn.lock
index af8ea47d1..ad3f33493 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2970,6 +2970,7 @@ __metadata:
     "@scure/base": ^1.1.2
     "@types/debug": ^4.1.8
     debug: ^4.3.4
+    eventemitter3: ^5.0.1
     light-bolt11-decoder: ^3.0.0
     typescript: ^5.2.2
   languageName: unknown