From f30a9075a229503204a50bca9088ecc40f49ca41 Mon Sep 17 00:00:00 2001
From: Kieran <kieran@harkin.me>
Date: Tue, 28 Feb 2023 19:25:10 +0000
Subject: [PATCH] bug: prevent multiple parallel WebLN calls

---
 packages/app/src/Feed/EventPublisher.ts |  8 +--
 packages/app/src/Hooks/useWebln.ts      | 75 ++++++++++++++++++++++---
 packages/app/src/Util.ts                |  6 ++
 3 files changed, 73 insertions(+), 16 deletions(-)

diff --git a/packages/app/src/Feed/EventPublisher.ts b/packages/app/src/Feed/EventPublisher.ts
index f0b8174..7234e33 100644
--- a/packages/app/src/Feed/EventPublisher.ts
+++ b/packages/app/src/Feed/EventPublisher.ts
@@ -5,7 +5,7 @@ import { TaggedRawEvent } from "@snort/nostr";
 import { EventKind, Tag, Event as NEvent, RelaySettings } from "@snort/nostr";
 import { RootState } from "State/Store";
 import { HexKey, RawEvent, u256, UserMetadata, Lists } from "@snort/nostr";
-import { bech32ToHex, unwrap } from "Util";
+import { bech32ToHex, delay, unwrap } from "Util";
 import { DefaultRelays, HashtagRegex } from "Const";
 import { System } from "System";
 
@@ -398,12 +398,6 @@ export default function useEventPublisher() {
 
 let isNip07Busy = false;
 
-const delay = (t: number) => {
-  return new Promise(resolve => {
-    setTimeout(resolve, t);
-  });
-};
-
 export const barrierNip07 = async <T>(then: () => Promise<T>): Promise<T> => {
   while (isNip07Busy) {
     await delay(10);
diff --git a/packages/app/src/Hooks/useWebln.ts b/packages/app/src/Hooks/useWebln.ts
index e5d0b33..b7b5717 100644
--- a/packages/app/src/Hooks/useWebln.ts
+++ b/packages/app/src/Hooks/useWebln.ts
@@ -1,25 +1,82 @@
 import { useEffect } from "react";
+import { delay, unwrap } from "Util";
 
-interface WebLNPaymentResponse {
-  paymentHash: string;
+let isWebLnBusy = false;
+export const barrierWebLn = async <T>(then: () => Promise<T>): Promise<T> => {
+  while (isWebLnBusy) {
+    await delay(10);
+  }
+  isWebLnBusy = true;
+  try {
+    return await then();
+  } finally {
+    isWebLnBusy = false;
+  }
+};
+
+interface SendPaymentResponse {
+  paymentHash?: string;
   preimage: string;
-  route: {
+  route?: {
     total_amt: number;
     total_fees: number;
   };
 }
+
+interface RequestInvoiceArgs {
+  amount?: string | number;
+  defaultAmount?: string | number;
+  minimumAmount?: string | number;
+  maximumAmount?: string | number;
+  defaultMemo?: string;
+}
+
+interface RequestInvoiceResponse {
+  paymentRequest: string;
+}
+
+interface GetInfoResponse {
+  node: {
+    alias: string;
+    pubkey: string;
+    color?: string;
+  };
+}
+
+interface SignMessageResponse {
+  message: string;
+  signature: string;
+}
+
+interface WebLN {
+  enabled: boolean;
+  getInfo(): Promise<GetInfoResponse>;
+  enable: () => Promise<void>;
+  makeInvoice(args: RequestInvoiceArgs): Promise<RequestInvoiceResponse>;
+  signMessage(message: string): Promise<SignMessageResponse>;
+  verifyMessage(signature: string, message: string): Promise<void>;
+  sendPayment: (pr: string) => Promise<SendPaymentResponse>;
+}
+
 declare global {
   interface Window {
-    webln?: {
-      enabled: boolean;
-      enable: () => Promise<void>;
-      sendPayment: (pr: string) => Promise<WebLNPaymentResponse>;
-    };
+    webln?: WebLN;
   }
 }
 
 export default function useWebln(enable = true) {
-  const maybeWebLn = "webln" in window ? window.webln : null;
+  const maybeWebLn =
+    "webln" in window && window.webln
+      ? ({
+          enabled: unwrap(window.webln).enabled,
+          getInfo: () => barrierWebLn(() => unwrap(window.webln).getInfo()),
+          enable: () => barrierWebLn(() => unwrap(window.webln).enable()),
+          makeInvoice: args => barrierWebLn(() => unwrap(window.webln).makeInvoice(args)),
+          signMessage: msg => barrierWebLn(() => unwrap(window.webln).signMessage(msg)),
+          verifyMessage: (sig, msg) => barrierWebLn(() => unwrap(window.webln).verifyMessage(sig, msg)),
+          sendPayment: pr => barrierWebLn(() => unwrap(window.webln).sendPayment(pr)),
+        } as WebLN)
+      : null;
 
   useEffect(() => {
     if (maybeWebLn && !maybeWebLn.enabled && enable) {
diff --git a/packages/app/src/Util.ts b/packages/app/src/Util.ts
index 4ee046a..c5fdab6 100644
--- a/packages/app/src/Util.ts
+++ b/packages/app/src/Util.ts
@@ -229,3 +229,9 @@ export function splitByUrl(str: string) {
 
   return str.split(urlRegex);
 }
+
+export const delay = (t: number) => {
+  return new Promise(resolve => {
+    setTimeout(resolve, t);
+  });
+};