From 40b7f8f90f1a3abbe21446cef9b53f17cddc1fce Mon Sep 17 00:00:00 2001
From: Chris Duncan <chris@zoso.dev>
Date: Fri, 19 Sep 2025 22:47:51 -0700
Subject: [PATCH] Wait for polling to end before executing command.

---
 src/lib/ledger.ts | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/src/lib/ledger.ts b/src/lib/ledger.ts
index 4f7d989..5e9034b 100644
--- a/src/lib/ledger.ts
+++ b/src/lib/ledger.ts
@@ -42,6 +42,7 @@ interface LedgerSignResponse extends LedgerResponse {
 */
 export class Ledger {
 	static #isBusy: boolean = false
+	static #isPolling?: Promise<void>
 	static #listenTimeout: 30000 = 30000
 	static #openTimeout: 3000 = 3000
 	static #status: LedgerStatus = 'DISCONNECTED'
@@ -131,6 +132,7 @@ export class Ledger {
 		}
 		try {
 			this.#isBusy = true
+			await this.#isPolling
 			if (typeof index !== 'number' || index < 0 || index >= HARDENED_OFFSET) {
 				throw new TypeError('Invalid account index')
 			}
@@ -355,6 +357,7 @@ export class Ledger {
 	static async #cacheBlock (index: number = 0, block: Block): Promise<LedgerResponse> {
 		try {
 			this.#isBusy = true
+			await this.#isPolling
 			if (typeof index !== 'number' || index < 0 || index >= HARDENED_OFFSET) {
 				throw new TypeError('Invalid account index')
 			}
@@ -413,6 +416,7 @@ export class Ledger {
 	static async #close (): Promise<LedgerResponse> {
 		try {
 			this.#isBusy = true
+			await this.#isPolling
 			const transport = await this.#transport.create(this.#openTimeout, this.#listenTimeout)
 			const response = await transport
 				.send(0xb0, 0xa7, this.#ADPU_CODES.paramUnused, this.#ADPU_CODES.paramUnused)
@@ -441,6 +445,7 @@ export class Ledger {
 	static async #open (): Promise<LedgerResponse> {
 		try {
 			this.#isBusy = true
+			await this.#isPolling
 			const name = new TextEncoder().encode('Nano')
 			const transport = await this.#transport.create(this.#openTimeout, this.#listenTimeout)
 			const response = await transport
@@ -465,12 +470,15 @@ export class Ledger {
 	* device.
 	*/
 	static async #poll (): Promise<void> {
+		let resolve: (() => void) | undefined
+		const poll = new Promise<void>(r => resolve = r)
+		this.#isPolling = poll
 		try {
+			const isHidPaired = (await navigator.hid?.getDevices())
+				.some(device => device.vendorId === this.ledgerVendorId)
+			const isUsbPaired = (await navigator.usb?.getDevices())
+				.some(device => device.vendorId === this.ledgerVendorId)
 			if (!this.#isBusy) {
-				const isHidPaired = (await navigator.hid?.getDevices())
-					.some(device => device.vendorId === this.ledgerVendorId)
-				const isUsbPaired = (await navigator.usb?.getDevices())
-					.some(device => device.vendorId === this.ledgerVendorId)
 				if (this.#transport === TransportHID && isHidPaired) {
 					await this.connect()
 				} else if (this.#transport === TransportUSB && isUsbPaired) {
@@ -484,7 +492,9 @@ export class Ledger {
 			console.warn('Error polling Ledger device')
 			this.#status = 'DISCONNECTED'
 		} finally {
-			setTimeout(() => this.#poll(), 1000)
+			resolve?.()
+			this.#isPolling = undefined
+			setTimeout(() => this.#poll(), 200)
 		}
 	}
 
@@ -498,6 +508,7 @@ export class Ledger {
 	static async #signBlock (index: number, block: Block): Promise<LedgerSignResponse> {
 		try {
 			this.#isBusy = true
+			await this.#isPolling
 			if (typeof index !== 'number' || index < 0 || index >= HARDENED_OFFSET) {
 				throw new TypeError('Invalid account index')
 			}
@@ -554,6 +565,7 @@ export class Ledger {
 	static async #signNonce (index: number, nonce: Uint8Array<ArrayBuffer>): Promise<LedgerSignResponse> {
 		try {
 			this.#isBusy = true
+			await this.#isPolling
 			if (typeof index !== 'number' || index < 0 || index >= HARDENED_OFFSET) {
 				throw new TypeError('Invalid account index')
 			}
@@ -598,6 +610,7 @@ export class Ledger {
 	static async #version (): Promise<LedgerVersionResponse> {
 		try {
 			this.#isBusy = true
+			await this.#isPolling
 			const transport = await this.#transport.create(this.#openTimeout, this.#listenTimeout)
 			const response = await transport
 				.send(0xb0, this.#ADPU_CODES.version, this.#ADPU_CODES.paramUnused, this.#ADPU_CODES.paramUnused)
-- 
2.47.3