Add opt-in support for routing local HTML files

README.md

@@ -37,6 +37,7 @@ them permanently.
 - **Registers as a browser** — per-user registry (no admin), guided first-run setup, health checks with one-click fixes
 - **Browser & profile discovery** — installed browsers, Chromium profiles, Firefox profiles, Firefox Multi-Account Containers, incognito/private entries, with real profile avatars
 - **Rules engine** — substring/regex match on whole URL, domain or path; drag-to-reorder priority; fallback default profile; bt-compatible rule syntax (`scope:domain|priority:2|github.com`)
+- **Optional local HTML routing** — when enabled in Settings, Browser Wrangler advertises `.htm/.html` support in Windows so local HTML files can be routed by your rules
 - **URL pipeline** — Outlook Safelinks unwrap, optional shortened-link expansion, and find/replace substitutions (`substr|find|replace`, `rgx|find|replace`)
 - **Picker** — popup listing browsers/profiles with number-key shortcuts; triggered by hotkeys (Ctrl+Shift etc.), rule conflicts, or no-match
 - **Toast** — brief notification showing which rule routed to which browser

src/BrowserWrangler.Core/AppInfo.cs

@@ -10,7 +10,7 @@ public static class AppInfo
     public const bool IsDevChannel = true;
     public const string Name = DevName;
 
-    /// <summary>ProgId registered for http/https URL associations.</summary>
+    /// <summary>ProgId registered for URL associations (and optional .htm/.html file associations).</summary>
     public const string ProgId = "BrowserWranglerHTM.Dev";
 
     /// <summary>Custom protocol for browser extensions ("x-bw:...").</summary>
@@ -22,7 +22,7 @@ public static class AppInfo
     public const bool IsDevChannel = false;
     public const string Name = StableName;
 
-    /// <summary>ProgId registered for http/https URL associations.</summary>
+    /// <summary>ProgId registered for URL associations (and optional .htm/.html file associations).</summary>
     public const string ProgId = "BrowserWranglerHTM";
 
     /// <summary>Custom protocol for browser extensions ("x-bw:...").</summary>

src/BrowserWrangler.Core/Configuration/AppConfig.cs

@@ -94,6 +94,12 @@ public sealed class AppConfig
     /// <summary>Set once the user has been through (or dismissed) the first-run setup window.</summary>
     public bool SetupCompleted { get; set; }
 
+    /// <summary>
+    /// When enabled, Browser Wrangler advertises support for .htm/.html files and routes them
+    /// through the same rule engine as links.
+    /// </summary>
+    public bool HandleHtmlFiles { get; set; }
+
     public PickerSettings Picker { get; set; } = new();
 
     public ToastSettings Toast { get; set; } = new();

src/BrowserWrangler.Core/Launching/LaunchTargetParser.cs

@@ -0,0 +1,80 @@
+namespace BrowserWrangler.Core.Launching;
+
+/// <summary>Parses and normalizes incoming launch arguments into routable targets.</summary>
+public static class LaunchTargetParser
+{
+    public static bool TryGetLaunchTargetUrl(
+        IEnumerable<string> args,
+        string customProtocol,
+        bool allowHtmlFileTargets,
+        out string launchTargetUrl)
+    {
+        foreach (string arg in args)
+        {
+            if (TryNormalizeLaunchTarget(arg, customProtocol, allowHtmlFileTargets, out launchTargetUrl))
+            {
+                return true;
+            }
+        }
+
+        launchTargetUrl = string.Empty;
+        return false;
+    }
+
+    public static bool TryNormalizeLaunchTarget(
+        string candidate,
+        string customProtocol,
+        bool allowHtmlFileTargets,
+        out string launchTargetUrl)
+    {
+        launchTargetUrl = string.Empty;
+        if (string.IsNullOrWhiteSpace(candidate))
+        {
+            return false;
+        }
+
+        if (candidate.StartsWith("http://", StringComparison.OrdinalIgnoreCase)
+            || candidate.StartsWith("https://", StringComparison.OrdinalIgnoreCase)
+            || candidate.StartsWith(customProtocol + ":", StringComparison.OrdinalIgnoreCase))
+        {
+            launchTargetUrl = candidate;
+            return true;
+        }
+
+        if (!allowHtmlFileTargets)
+        {
+            return false;
+        }
+
+        if (Uri.TryCreate(candidate, UriKind.Absolute, out Uri? parsedUri)
+            && parsedUri.Scheme == Uri.UriSchemeFile
+            && IsHtmlPath(parsedUri.LocalPath))
+        {
+            launchTargetUrl = parsedUri.AbsoluteUri;
+            return true;
+        }
+
+        if (!Path.IsPathRooted(candidate) || !IsHtmlPath(candidate))
+        {
+            return false;
+        }
+
+        try
+        {
+            string fullPath = Path.GetFullPath(candidate);
+            launchTargetUrl = new Uri(fullPath).AbsoluteUri;
+            return true;
+        }
+        catch (Exception ex) when (ex is ArgumentException or NotSupportedException or PathTooLongException or UriFormatException)
+        {
+            return false;
+        }
+    }
+
+    private static bool IsHtmlPath(string path)
+    {
+        string extension = Path.GetExtension(path);
+        return extension.Equals(".htm", StringComparison.OrdinalIgnoreCase)
+            || extension.Equals(".html", StringComparison.OrdinalIgnoreCase);
+    }
+}

src/BrowserWrangler.Core/Setup/BrowserRegistration.cs

@@ -59,10 +59,10 @@ public static class BrowserRegistration
     /// <summary>Full path of the executable to register; defaults to the current process.</summary>
     public static string ExecutablePath { get; set; } = Environment.ProcessPath ?? string.Empty;
 
-    public static void RegisterAll()
+    public static void RegisterAll(bool includeHtmlFileAssociations = false)
     {
         RegisterCustomProtocol();
-        RegisterBrowser();
+        RegisterBrowser(includeHtmlFileAssociations);
         NotifyShellAssociationsChanged();
     }
 
@@ -82,16 +82,21 @@ public static void UnregisterAll()
     /// single registry read in the common case and never throws.
     /// </summary>
     /// <returns>True when a repair was performed.</returns>
-    public static bool EnsureRegistered()
+    public static bool EnsureRegistered(bool includeHtmlFileAssociations = false)
     {
         try
         {
-            if (ExecutablePath.Length == 0 || IsRegisteredAsBrowser(out _))
+            if (ExecutablePath.Length == 0)
             {
                 return false;
             }
 
-            RegisterAll();
+            if (IsRegisteredAsBrowser(out _) && HasExpectedHtmlFileAssociations(includeHtmlFileAssociations))
+            {
+                return false;
+            }
+
+            RegisterAll(includeHtmlFileAssociations);
             return true;
         }
         catch (Exception ex) when (ex is UnauthorizedAccessException or IOException or System.Security.SecurityException)
@@ -101,23 +106,46 @@ public static bool EnsureRegistered()
         }
     }
 
-    /// <summary>Registers under StartMenuInternet with http/https capabilities.</summary>
-    public static void RegisterBrowser()
+    public static IReadOnlyList<string> GetRegisteredUrlProtocols() =>
+    [
+        "https",
+        "http",
+        AppInfo.CustomProtocol,
+    ];
+
+    public static IReadOnlyList<string> GetRegisteredFileExtensions(bool includeHtmlFileAssociations) =>
+        includeHtmlFileAssociations
+            ?
+            [
+                ".htm",
+                ".html",
+            ]
+            : [];
+
+    /// <summary>Registers under StartMenuInternet with URL capabilities and optional HTML file associations.</summary>
+    public static void RegisterBrowser(bool includeHtmlFileAssociations = false)
     {
         string appPath = ExecutablePath;
         string capRoot = BrowserRegPath + @"\Capabilities";
+        string fileAssociationsPath = capRoot + @"\FileAssociations";
 
         SetValue(BrowserRegPath, null, AppInfo.Name);
 
         SetValue(capRoot, "ApplicationName", AppInfo.Name);
         SetValue(capRoot, "ApplicationDescription", AppInfo.Description);
         SetValue(capRoot, "ApplicationIcon", appPath + ",0");
 
-        foreach (string protocol in new[] { "https", "http", AppInfo.CustomProtocol })
+        foreach (string protocol in GetRegisteredUrlProtocols())
         {
             SetValue(capRoot + @"\URLAssociations", protocol, AppInfo.ProgId);
         }
 
+        Registry.CurrentUser.DeleteSubKeyTree(fileAssociationsPath, throwOnMissingSubKey: false);
+        foreach (string extension in GetRegisteredFileExtensions(includeHtmlFileAssociations))
+        {
+            SetValue(fileAssociationsPath, extension, AppInfo.ProgId);
+        }
+
         SetValue(BrowserRegPath + @"\DefaultIcon", null, appPath + ",0");
         SetValue(BrowserRegPath + @"\shell\open\command", null, $"\"{appPath}\"");
 
@@ -149,6 +177,31 @@ public static bool IsRegisteredAsBrowser(out string error)
         return ok;
     }
 
+    private static bool HasExpectedHtmlFileAssociations(bool includeHtmlFileAssociations)
+    {
+        using RegistryKey? fileAssociations = Registry.CurrentUser.OpenSubKey(BrowserRegPath + @"\Capabilities\FileAssociations");
+        IReadOnlyList<string> extensions = GetRegisteredFileExtensions(includeHtmlFileAssociations);
+        if (extensions.Count == 0)
+        {
+            return fileAssociations is null;
+        }
+
+        if (fileAssociations is null)
+        {
+            return false;
+        }
+
+        foreach (string extension in extensions)
+        {
+            if (!string.Equals(fileAssociations.GetValue(extension) as string, AppInfo.ProgId, StringComparison.Ordinal))
+            {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
     /// <summary>True when http/https default handlers point at our ProgId.</summary>
     public static bool IsDefaultBrowser(out bool http, out bool https)
     {
@@ -209,7 +262,7 @@ public static List<SystemCheck> GetChecks() =>
                 bool ok = IsRegisteredAsBrowser(out string error);
                 return (ok, error);
             },
-            RegisterAll),
+            () => RegisterAll()),
         new SystemCheck(
             "proto_http",
             "HTTP Protocol Handler",

src/BrowserWrangler/MainWindow.xaml.cs

@@ -44,7 +44,7 @@ private void OnActivated(object sender, WindowActivatedEventArgs args)
 
     private void FixDefaultBrowser_Click(object sender, RoutedEventArgs e)
     {
-        BrowserRegistration.EnsureRegistered();
+        BrowserRegistration.EnsureRegistered(AppState.Config.HandleHtmlFiles);
         BrowserRegistration.OpenDefaultAppsSettings();
     }
 

src/BrowserWrangler/Pages/HealthPage.xaml.cs

@@ -1,4 +1,5 @@
 using BrowserWrangler.Core.Setup;
+using BrowserWrangler.Services;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 
@@ -72,7 +73,7 @@ private void Recheck()
 
     private void Register_Click(object sender, RoutedEventArgs e)
     {
-        BrowserRegistration.RegisterAll();
+        BrowserRegistration.RegisterAll(AppState.Config.HandleHtmlFiles);
         Recheck();
     }
 

src/BrowserWrangler/Pages/SettingsPage.xaml

@@ -55,6 +55,17 @@
                 TextWrapping="Wrap"
                 Text="Follows HTTP redirects before matching so rules can see the final destination. This can add latency and shares clicked URLs with redirect services." />
 
+            <TextBlock Margin="0,16,0,0" Style="{StaticResource SubtitleTextBlockStyle}" Text="File routing" />
+            <ToggleSwitch
+                x:Name="HandleHtmlFilesEnabled"
+                Header="Route local .htm/.html files"
+                Toggled="Setting_Changed" />
+            <TextBlock
+                FontSize="12"
+                Opacity="0.7"
+                TextWrapping="Wrap"
+                Text="When enabled, Browser Wrangler advertises support for .htm/.html in Windows so those files can be routed by your rules." />
+
             <TextBlock Margin="0,16,0,0" Style="{StaticResource SubtitleTextBlockStyle}" Text="Toast" />
             <ToggleSwitch x:Name="ToastEnabled" Header="Show toast when a URL is routed" Toggled="Setting_Changed" />
             <Slider

src/BrowserWrangler/Pages/SettingsPage.xaml.cs

@@ -1,4 +1,5 @@
 using BrowserWrangler.Core.Configuration;
+using BrowserWrangler.Core.Setup;
 using BrowserWrangler.Services;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
@@ -33,6 +34,7 @@ public SettingsPage()
         ToastDuration.Value = AppState.Config.Toast.VisibleSeconds;
         SafelinksEnabled.IsOn = AppState.Config.Pipeline.UnwrapSafelinks;
         ExpandShortLinksEnabled.IsOn = AppState.Config.Pipeline.ExpandShortenedUrls;
+        HandleHtmlFilesEnabled.IsOn = AppState.Config.HandleHtmlFiles;
         LogRuleHitsEnabled.IsOn = AppState.Config.LogRuleHits;
         AutoCheckUpdatesEnabled.IsOn = AppState.Config.Updates.AutoCheckEnabled;
         UpdateIntervalHours.Value = AppState.Config.Updates.CheckIntervalHours;
@@ -66,9 +68,12 @@ private void Setting_Changed(object sender, RoutedEventArgs e)
 
         bool oldAutoCheckEnabled = false;
         bool newAutoCheckEnabled = false;
+        bool oldHandleHtmlFiles = false;
+        bool newHandleHtmlFiles = false;
         AppState.MutateAndSave(config =>
         {
             oldAutoCheckEnabled = config.Updates.AutoCheckEnabled;
+            oldHandleHtmlFiles = config.HandleHtmlFiles;
             PickerSettings p = config.Picker;
             p.OnCtrlShift = PickerCtrlShift.IsChecked == true;
             p.OnCtrlAlt = PickerCtrlAlt.IsChecked == true;
@@ -78,16 +83,23 @@ private void Setting_Changed(object sender, RoutedEventArgs e)
             config.Toast.ShowOnOpen = ToastEnabled.IsOn;
             config.Pipeline.UnwrapSafelinks = SafelinksEnabled.IsOn;
             config.Pipeline.ExpandShortenedUrls = ExpandShortLinksEnabled.IsOn;
+            config.HandleHtmlFiles = HandleHtmlFilesEnabled.IsOn;
             config.LogRuleHits = LogRuleHitsEnabled.IsOn;
             config.Updates.AutoCheckEnabled = AutoCheckUpdatesEnabled.IsOn;
             config.Updates.AutoDownloadInstaller = AutoDownloadInstallerEnabled.IsOn;
             newAutoCheckEnabled = config.Updates.AutoCheckEnabled;
+            newHandleHtmlFiles = config.HandleHtmlFiles;
         });
 
         if (oldAutoCheckEnabled != newAutoCheckEnabled)
         {
             AppState.Updates.NotifyScheduleChanged();
         }
+
+        if (oldHandleHtmlFiles != newHandleHtmlFiles)
+        {
+            BrowserRegistration.RegisterAll(newHandleHtmlFiles);
+        }
     }
 
     private void Slider_Changed(object sender, RangeBaseValueChangedEventArgs e)

src/BrowserWrangler/Program.cs

@@ -47,7 +47,7 @@ public static int Main(string[] args)
         // installer hooks: silent register/unregister of the browser (per-user registry)
         if (args.Contains("--register", StringComparer.OrdinalIgnoreCase))
         {
-            Core.Setup.BrowserRegistration.RegisterAll();
+            Core.Setup.BrowserRegistration.RegisterAll(config.HandleHtmlFiles);
             return 0;
         }
 
@@ -61,22 +61,17 @@ public static int Main(string[] args)
         bool firstRun = args.Contains("--first-run", StringComparer.OrdinalIgnoreCase);
         if (firstRun)
         {
-            Core.Setup.BrowserRegistration.EnsureRegistered();
+            Core.Setup.BrowserRegistration.EnsureRegistered(config.HandleHtmlFiles);
             return StartConfigInstance(LaunchMode.Welcome);
         }
 
-        string? url = args.FirstOrDefault(a =>
-            a.StartsWith("http://", StringComparison.OrdinalIgnoreCase) ||
-            a.StartsWith("https://", StringComparison.OrdinalIgnoreCase) ||
-            a.StartsWith(Core.AppInfo.CustomProtocol + ":", StringComparison.OrdinalIgnoreCase));
-
-        if (url is not null)
+        if (LaunchTargetParser.TryGetLaunchTargetUrl(args, Core.AppInfo.CustomProtocol, config.HandleHtmlFiles, out string url))
         {
             return HandleUrl(config, url);
         }
 
         // a moved or upgraded install leaves stale registry paths behind - repair them silently
-        Core.Setup.BrowserRegistration.EnsureRegistered();
+        Core.Setup.BrowserRegistration.EnsureRegistered(config.HandleHtmlFiles);
 
         // users who never saw the post-install window get it the first time they open the app
         bool needsSetup = !config.SetupCompleted &&

src/BrowserWrangler/WelcomeWindow.xaml.cs

@@ -142,7 +142,7 @@ private static void MarkSetupCompleted()
 
     private void Register_Click(object sender, RoutedEventArgs e)
     {
-        BrowserRegistration.RegisterAll();
+        BrowserRegistration.RegisterAll(AppState.Config.HandleHtmlFiles);
         Refresh();
     }