From 3b4bb7f0df1ab873f08c1618545fbe395eb4fcd4 Mon Sep 17 00:00:00 2001
From: thePR0M3TH3AN <53631862+PR0M3TH3AN@users.noreply.github.com>
Date: Wed, 24 Sep 2025 20:53:54 -0400
Subject: [PATCH] Add form magnet normalizer and tests

---
 js/magnet.js                | 177 +++++++++++++++++++++++++++++++++---
 tests/magnet-utils.test.mjs |   7 ++
 2 files changed, 171 insertions(+), 13 deletions(-)

diff --git a/js/magnet.js b/js/magnet.js
index 2f5934e9..5fe5d80c 100644
--- a/js/magnet.js
+++ b/js/magnet.js
@@ -1,19 +1,170 @@
 import { WSS_TRACKERS } from "./constants.js";
-import { normalizeAndAugmentMagnet as normalizeLegacy } from "./magnetUtils.js";
 
-export function normalizeAndAugmentMagnet(rawValue, { ws = "", xs = "" } = {}) {
-  const trimmedInput = typeof rawValue === "string" ? rawValue.trim() : "";
-  const trimmedWs = typeof ws === "string" ? ws.trim() : "";
-  const trimmedXs = typeof xs === "string" ? xs.trim() : "";
+const HEX_INFO_HASH = /^[0-9a-f]{40}$/i;
+const ENCODED_BTih_PATTERN = /xt=urn%3Abtih%3A([0-9a-z]+)/gi;
 
-  const webSeeds = trimmedWs ? [trimmedWs] : [];
+function getOriginProtocol() {
+  if (typeof window !== "undefined" && window.location?.protocol) {
+    return window.location.protocol.toLowerCase();
+  }
+  return "https:";
+}
 
-  const result = normalizeLegacy(trimmedInput, {
-    webSeed: webSeeds,
-    torrentUrl: trimmedXs,
-    xs: trimmedXs,
-    extraTrackers: WSS_TRACKERS,
-  });
+function decodeLoose(value) {
+  if (typeof value !== "string") {
+    return "";
+  }
+  const trimmed = value.trim();
+  if (!trimmed) {
+    return "";
+  }
+  try {
+    return decodeURIComponent(trimmed);
+  } catch (err) {
+    return trimmed;
+  }
+}
 
-  return result.magnet;
+function normalizeForComparison(value) {
+  if (typeof value !== "string") {
+    return "";
+  }
+  return value.trim().replace(/\/+$/, "").toLowerCase();
+}
+
+function tryFormatAbsoluteUrl(candidate) {
+  if (typeof candidate !== "string") {
+    return "";
+  }
+  const trimmed = candidate.trim();
+  if (!trimmed) {
+    return "";
+  }
+  try {
+    const parsed = new URL(trimmed);
+    return parsed.toString();
+  } catch (err) {
+    return trimmed;
+  }
+}
+
+/**
+ * Normalize and enrich a magnet string entered in the upload form so that it
+ * always produces a WebTorrent-friendly URI. The logic mirrors the behaviour of
+ * the legacy magnetUtils helper but returns a plain string for ease of use.
+ */
+export function normalizeAndAugmentMagnet(rawValue, { ws = "", xs = "" } = {}) {
+  const initial = typeof rawValue === "string" ? rawValue.trim() : "";
+  if (!initial) {
+    return "";
+  }
+
+  let working = initial;
+
+  if (HEX_INFO_HASH.test(working)) {
+    working = `magnet:?xt=urn:btih:${working.toLowerCase()}`;
+  }
+
+  working = working.replace(ENCODED_BTih_PATTERN, (_, hash) => `xt=urn:btih:${hash}`);
+
+  if (!/^magnet:/i.test(working)) {
+    return working;
+  }
+
+  let fragment = "";
+  const hashIndex = working.indexOf("#");
+  if (hashIndex !== -1) {
+    fragment = working.slice(hashIndex);
+    working = working.slice(0, hashIndex);
+  }
+
+  const [, queryPart = ""] = working.split("?", 2);
+  const normalizedScheme = "magnet:";
+  const rawParams = queryPart
+    .split("&")
+    .map((part) => part.trim())
+    .filter(Boolean);
+
+  const params = [];
+
+  for (const rawParam of rawParams) {
+    const [rawKey, rawVal = ""] = rawParam.split("=", 2);
+    const key = rawKey.trim();
+    if (!key) {
+      continue;
+    }
+    let value = rawVal.trim();
+    if (key.toLowerCase() === "xt" && value) {
+      const decoded = decodeLoose(value);
+      if (decoded) {
+        value = decoded;
+      }
+    }
+    params.push({
+      key,
+      value,
+      lowerKey: key.toLowerCase(),
+      compareValue: normalizeForComparison(value),
+    });
+  }
+
+  const appendUniqueParam = (key, value) => {
+    if (!value) {
+      return;
+    }
+    const trimmedValue = value.trim();
+    if (!trimmedValue) {
+      return;
+    }
+    const lowerKey = key.toLowerCase();
+    const compareValue = normalizeForComparison(trimmedValue);
+    if (compareValue) {
+      const exists = params.some(
+        (param) => param.lowerKey === lowerKey && param.compareValue === compareValue
+      );
+      if (exists) {
+        return;
+      }
+    }
+    params.push({
+      key,
+      value: trimmedValue,
+      lowerKey,
+      compareValue,
+    });
+  };
+
+  for (const tracker of WSS_TRACKERS) {
+    if (typeof tracker !== "string") {
+      continue;
+    }
+    const trimmedTracker = tracker.trim();
+    if (!/^wss:\/\//i.test(trimmedTracker)) {
+      continue;
+    }
+    appendUniqueParam("tr", trimmedTracker);
+  }
+
+  const normalizedXs = typeof xs === "string" ? xs.trim() : "";
+  if (normalizedXs) {
+    appendUniqueParam("xs", normalizedXs);
+  }
+
+  const originProtocol = getOriginProtocol();
+  const rawWs = typeof ws === "string" ? ws.trim() : "";
+  if (rawWs) {
+    const formattedWs = tryFormatAbsoluteUrl(rawWs);
+    const lowerWs = formattedWs.toLowerCase();
+    const isHttpSeed = lowerWs.startsWith("http://");
+    const allowHttpSeed = originProtocol === "http:";
+    if (!isHttpSeed || allowHttpSeed) {
+      appendUniqueParam("ws", formattedWs);
+    }
+  }
+
+  const queryString = params
+    .map(({ key, value }) => (value ? `${key}=${value}` : key))
+    .join("&");
+
+  return `${normalizedScheme}${queryString ? `?${queryString}` : ""}${fragment}`;
 }
diff --git a/tests/magnet-utils.test.mjs b/tests/magnet-utils.test.mjs
index 6d0aad55..1297664c 100644
--- a/tests/magnet-utils.test.mjs
+++ b/tests/magnet-utils.test.mjs
@@ -135,6 +135,13 @@ function getParamValues(magnet, key) {
     ["https://cdn.example.com/video.torrent"],
     "Expected xs hint to be appended"
   );
+  const trackers = parsed.searchParams.getAll("tr");
+  for (const tracker of WSS_TRACKERS) {
+    assert.ok(
+      trackers.includes(tracker),
+      `Expected helper to append tracker ${tracker}`
+    );
+  }
 })();
 
 (function testFormHelperSkipsInsecureWsOnHttpsOrigin() {