From cc8459c161a1fff47ab0ecef330201c83dba1f5f Mon Sep 17 00:00:00 2001
From: McToel <theo.doellmann@gmx.de>
Date: Thu, 20 Feb 2025 23:45:44 +0100
Subject: [PATCH] using math.random instead of webcrypto and reintroduced
 randomizeUserAgent

---
 lib/request.js | 30 +++++++++++++++++++++---------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/lib/request.js b/lib/request.js
index db88b76b..f6643a7a 100644
--- a/lib/request.js
+++ b/lib/request.js
@@ -3,13 +3,23 @@ import {Request, fetch} from 'cross-fetch';
 import {parse as parseContentType} from 'content-type';
 import {HafasError} from './errors.js';
 
-const randomBytesHex = (nBytes = 8) => {
-	const array = new Uint8Array(nBytes);
-	crypto.getRandomValues(array);
-	return Array.from(array)
-		.map((byte) => byte.toString(16)
-			.padStart(2, '0'))
-		.join('');
+const randomBytesHexString = length => [...Array(length)].map(() => Math.floor(Math.random() * 16)
+	.toString(16))
+	.join('');
+
+const id = randomBytesHexString(6)
+	.toString('hex');
+const randomizeUserAgent = (userAgent) => {
+	let ua = userAgent;
+	for (
+		let i = Math.round(5 + Math.random() * 5);
+		i < ua.length;
+		i += Math.round(5 + Math.random() * 5)
+	) {
+		ua = ua.slice(0, i) + id + ua.slice(i);
+		i += id.length;
+	}
+	return ua;
 };
 
 const checkIfResponseIsOk = (_) => {
@@ -65,7 +75,9 @@ const request = async (ctx, userAgent, reqData) => {
 			'Accept-Encoding': 'gzip, br, deflate',
 			'Accept': 'application/json',
 			'Accept-Language': opt.language || profile.defaultLanguage || 'en',
-			'user-agent': userAgent,
+			'user-agent': profile.randomizeUserAgent
+				? randomizeUserAgent(userAgent)
+				: userAgent,
 			...reqData.headers,
 		},
 		redirect: 'follow',
@@ -76,7 +88,7 @@ const request = async (ctx, userAgent, reqData) => {
 	if (reqOptions.query) {
 		url += '?' + stringify(reqOptions.query, {arrayFormat: 'brackets', encodeValuesOnly: true});
 	}
-	const reqId = randomBytesHex(3);
+	const reqId = randomBytesHexString(6);
 	const fetchReq = new Request(url, reqOptions);
 	profile.logRequest(ctx, fetchReq, reqId);