fix: use custom user data dir for updater WebView2

The default location was in the install directory, which is not
writeable by regular users. We now store the WebView2 data directory in
our AppData/Local folder.

Author: deansheather

App/App.csproj

@@ -17,6 +17,8 @@
         <LangVersion>preview</LangVersion>
         <!-- We have our own implementation of main with exception handling -->
         <DefineConstants>DISABLE_XAML_GENERATED_MAIN;DISABLE_XAML_GENERATED_BREAK_ON_UNHANDLED_EXCEPTION</DefineConstants>
+        <!-- Default version for debug builds, overridden during releases -->
+        <Version>0.1.0.0</Version>
 
         <AssemblyName>Coder Desktop</AssemblyName>
         <AssemblyTitle>Coder Desktop</AssemblyTitle>

App/ViewModels/UpdaterUpdateAvailableViewModel.cs

@@ -4,10 +4,12 @@
 using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
+using Coder.Desktop.App.Services;
 using CommunityToolkit.Mvvm.ComponentModel;
 using Microsoft.Extensions.Logging;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
+using Microsoft.Web.WebView2.Core;
 using NetSparkleUpdater;
 using NetSparkleUpdater.Enums;
 using NetSparkleUpdater.Events;
@@ -174,8 +176,18 @@ public async Task Changelog_Loaded(object sender, RoutedEventArgs e)
         if (sender is not WebView2 webView)
             return;
 
-        // Start the engine.
-        await webView.EnsureCoreWebView2Async();
+        // Start the engine with a custom user data folder. The default for
+        // unpackaged WinUI 3 apps is to write to a subfolder in the app's
+        // install directory, which is Program Files by default and not
+        // writeable by the user.
+        var userDataFolder = Path.Join(SettingsManagerUtils.AppSettingsDirectory(), "WebView2");
+        _logger.LogDebug("Creating WebView2 user data folder at {UserDataFolder}", userDataFolder);
+        Directory.CreateDirectory(userDataFolder);
+        var env = await CoreWebView2Environment.CreateWithOptionsAsync(
+            null,
+            userDataFolder,
+            new CoreWebView2EnvironmentOptions());
+        await webView.EnsureCoreWebView2Async(env);
 
         // Disable unwanted features.
         var settings = webView.CoreWebView2.Settings;