WebUI: add versioning to local preferences

And provide migration path for changing preferences.

Fixes #22639.
PR #22677.

src/webui/www/private/scripts/client.js

@@ -174,7 +174,9 @@ let selectedStatus = LocalPreferences.get("selected_filter", "all");
 let setStatusFilter = () => {};
 let toggleFilterDisplay = () => {};
 
-window.addEventListener("DOMContentLoaded", () => {
+window.addEventListener("DOMContentLoaded", (event) => {
+    window.qBittorrent.LocalPreferences.upgrade();
+
     let isSearchPanelLoaded = false;
     let isLogPanelLoaded = false;
     let isRssPanelLoaded = false;

src/webui/www/private/scripts/localpreferences.js

@@ -1,5 +1,6 @@
 /*
  * Bittorrent Client using Qt and libtorrent.
+ * Copyright (C) 2025  Mike Tzou (Chocobo1)
  * Copyright (C) 2019  Thomas Piccirello <thomas.piccirello@gmail.com>
  *
  * This program is free software; you can redistribute it and/or
@@ -32,7 +33,8 @@ window.qBittorrent ??= {};
 window.qBittorrent.LocalPreferences ??= (() => {
     const exports = () => {
         return {
-            LocalPreferences: LocalPreferences
+            LocalPreferences: LocalPreferences,
+            upgrade: upgrade
         };
     };
 
@@ -53,6 +55,10 @@ window.qBittorrent.LocalPreferences ??= (() => {
             }
         }
 
+        size() {
+            return localStorage.length;
+        }
+
         remove(key) {
             try {
                 localStorage.removeItem(key);
@@ -63,6 +69,40 @@ window.qBittorrent.LocalPreferences ??= (() => {
         }
     };
 
+    const localPreferences = new LocalPreferences();
+
+    const upgrade = () => {
+        const MIGRATION_VERSION = 1;
+        const MIGRATION_VERSION_KEY = "MigrationVersion";
+
+        // clean start
+        if (localPreferences.size() === 0) {
+            localPreferences.set(MIGRATION_VERSION_KEY, MIGRATION_VERSION);
+            return;
+        }
+
+        // already in use
+        const version = Number(localPreferences.get(MIGRATION_VERSION_KEY)); // `0` on first initialization
+        if (version !== MIGRATION_VERSION) {
+            if (version < 1)
+                resetSideFilters();
+
+            localPreferences.set(MIGRATION_VERSION_KEY, MIGRATION_VERSION);
+        }
+    };
+
+    const resetSideFilters = () => {
+        // conditionally reset the filter to default to avoid none selected
+        const clear = (key) => {
+            const value = Number(localPreferences.get(key));
+            if ((value === 1) || (value === 2)) // affected values
+                localPreferences.remove(key);
+        };
+        clear("selected_category");
+        clear("selected_tag");
+        clear("selected_tracker");
+    };
+
     return exports();
 })();
 Object.freeze(window.qBittorrent.LocalPreferences);