Svg thumbnail failed rendering (#32936)

* [SVGThumbnail] Check fill-rule in SVG file and apply it.

* [SVGThumbnail] Comment added

* [SVGThumbnail] SvgContents is used instead of all html content.

* [SVGThumbnail] - Use SvgContents to extract and modify SVG styles efficiently
- Add retry logic and error handling for WebView2 initialization

* use Linq

---------

Co-authored-by: Jaime Bernardo <jaime@janeasystems.com>
Co-authored-by: Leilei Zhang <leilzh@microsoft.com>

src/modules/previewpane/SvgThumbnailProvider/SvgThumbnailProvider.cs

@@ -5,8 +5,7 @@ using System.Drawing.Drawing2D;
 using System.Globalization;
 using System.Reflection;
 using System.Runtime.CompilerServices;
-using System.Threading;
+using System.Xml.Linq;
-
 using Common.Utilities;
 using ManagedCommon;
 using Microsoft.Web.WebView2.Core;
@@ -118,92 +117,151 @@ namespace Microsoft.PowerToys.ThumbnailHandler.Svg
             _browser.Height = (int)cx;
             _browser.NavigationCompleted += async (object sender, CoreWebView2NavigationCompletedEventArgs args) =>
             {
-                var a = await _browser.ExecuteScriptAsync($"document.getElementsByTagName('svg')[0].viewBox;");
+                try
-                if (a != null)
                 {
-                    await _browser.ExecuteScriptAsync($"document.getElementsByTagName('svg')[0].style = 'width:100%;height:100%';");
+                    // Check if the SVG element is present
+                    var a = await _browser.ExecuteScriptAsync($"document.getElementsByTagName('svg')[0].viewBox;");
+                    if (a != null)
+                    {
+                        var svgContent = SvgContents.Substring(SvgContents.IndexOf("<svg", StringComparison.OrdinalIgnoreCase), SvgContents.IndexOf("</svg>", StringComparison.OrdinalIgnoreCase) - SvgContents.IndexOf("<svg", StringComparison.OrdinalIgnoreCase) + "</svg>".Length);
+
+                        Dictionary<string, string> styleDict = new Dictionary<string, string>();
+
+                        // Try to parse the SVG content
+                        try
+                        {
+                            // Attempt to parse the svgContent
+                            var svgDocument = XDocument.Parse(svgContent);
+                            var svgElement = svgDocument.Root;
+                            var currentStyle = svgElement?.Attribute("style")?.Value;
+
+                            // If style attribute exists, preserve existing styles
+                            if (!string.IsNullOrEmpty(currentStyle) && currentStyle != "null")
+                            {
+                                styleDict = currentStyle
+                                    .Split(';', StringSplitOptions.RemoveEmptyEntries)
+                                    .Select(stylePart => stylePart.Split(':', 2, StringSplitOptions.TrimEntries))
+                                    .Where(styleKeyValue => styleKeyValue.Length == 2 && !string.IsNullOrEmpty(styleKeyValue[0]))
+                                    .ToDictionary(
+                                        styleKeyValue => styleKeyValue[0],
+                                        styleKeyValue => styleKeyValue[1]);
+                            }
+                        }
+                        catch (Exception ex)
+                        {
+                            // Log the error if the SVG content is not valid or parsing fails
+                            Logger.LogError($"Failed to parse SVG content: {ex.Message}");
+                        }
+
+                        // Add or replace width and height in the existing style
+                        styleDict["width"] = "100%";
+                        styleDict["height"] = "100%";
+
+                        // Construct a single JavaScript string to set all properties
+                        var styleScript = string.Join(";", styleDict.Select(kv => $"document.getElementsByTagName('svg')[0].style.setProperty('{kv.Key}', '{kv.Value}');"));
+
+                        // Apply the new style attributes using the constructed script
+                        await _browser.ExecuteScriptAsync(styleScript);
+                    }
+
+                    // Hide scrollbar - fixes #18286
+                    await _browser.ExecuteScriptAsync("document.querySelector('body').style.overflow='hidden'");
+
+                    MemoryStream ms = new MemoryStream();
+                    await _browser.CoreWebView2.CapturePreviewAsync(CoreWebView2CapturePreviewImageFormat.Png, ms);
+                    thumbnail = new Bitmap(ms);
+
+                    if (thumbnail.Width != cx && thumbnail.Height != cx && thumbnail.Width != 0 && thumbnail.Height != 0)
+                    {
+                        // We are not the appropriate size for caller.  Resize now while
+                        // respecting the aspect ratio.
+                        float scale = Math.Min((float)cx / thumbnail.Width, (float)cx / thumbnail.Height);
+                        int scaleWidth = (int)(thumbnail.Width * scale);
+                        int scaleHeight = (int)(thumbnail.Height * scale);
+                        thumbnail = ResizeImage(thumbnail, scaleWidth, scaleHeight);
+                    }
+
+                    thumbnailDone.Set();
                 }
-
+                catch (Exception ex)
-                // Hide scrollbar - fixes #18286
-                await _browser.ExecuteScriptAsync("document.querySelector('body').style.overflow='hidden'");
-
-                MemoryStream ms = new MemoryStream();
-                await _browser.CoreWebView2.CapturePreviewAsync(CoreWebView2CapturePreviewImageFormat.Png, ms);
-                thumbnail = new Bitmap(ms);
-
-                if (thumbnail.Width != cx && thumbnail.Height != cx && thumbnail.Width != 0 && thumbnail.Height != 0)
                 {
-                    // We are not the appropriate size for caller.  Resize now while
+                    Logger.LogError("Error during NavigationCompleted: ", ex);
-                    // respecting the aspect ratio.
+                    thumbnailDone.Set();
-                    float scale = Math.Min((float)cx / thumbnail.Width, (float)cx / thumbnail.Height);
-                    int scaleWidth = (int)(thumbnail.Width * scale);
-                    int scaleHeight = (int)(thumbnail.Height * scale);
-                    thumbnail = ResizeImage(thumbnail, scaleWidth, scaleHeight);
                 }
-
-                thumbnailDone.Set();
             };
 
             var webView2Options = new CoreWebView2EnvironmentOptions("--block-new-web-contents");
             ConfiguredTaskAwaitable<CoreWebView2Environment>.ConfiguredTaskAwaiter
-               webView2EnvironmentAwaiter = CoreWebView2Environment
+                webView2EnvironmentAwaiter = CoreWebView2Environment
-                   .CreateAsync(userDataFolder: _webView2UserDataFolder, options: webView2Options)
+                    .CreateAsync(userDataFolder: _webView2UserDataFolder, options: webView2Options)
-                   .ConfigureAwait(true).GetAwaiter();
+                    .ConfigureAwait(true).GetAwaiter();
 
             webView2EnvironmentAwaiter.OnCompleted(async () =>
             {
-                try
+                for (int attempt = 0; attempt < 3; attempt++)
                 {
-                    _webView2Environment = webView2EnvironmentAwaiter.GetResult();
+                    try
-                    await _browser.EnsureCoreWebView2Async(_webView2Environment).ConfigureAwait(true);
-                    _browser.CoreWebView2.SetVirtualHostNameToFolderMapping(VirtualHostName, AssemblyDirectory, CoreWebView2HostResourceAccessKind.Deny);
-                    _browser.CoreWebView2.Settings.AreDefaultScriptDialogsEnabled = false;
-                    _browser.CoreWebView2.Settings.AreDefaultContextMenusEnabled = false;
-                    _browser.CoreWebView2.Settings.AreDevToolsEnabled = false;
-                    _browser.CoreWebView2.Settings.AreHostObjectsAllowed = false;
-                    _browser.CoreWebView2.Settings.IsGeneralAutofillEnabled = false;
-                    _browser.CoreWebView2.Settings.IsPasswordAutosaveEnabled = false;
-                    _browser.CoreWebView2.Settings.IsScriptEnabled = false;
-                    _browser.CoreWebView2.Settings.IsWebMessageEnabled = false;
-
-                    // Don't load any resources.
-                    _browser.CoreWebView2.AddWebResourceRequestedFilter("*", CoreWebView2WebResourceContext.All);
-                    _browser.CoreWebView2.WebResourceRequested += (object sender, CoreWebView2WebResourceRequestedEventArgs e) =>
                     {
-                        // Show local file we've saved with the svg contents. Block all else.
+                        _webView2Environment = webView2EnvironmentAwaiter.GetResult();
-                        if (new Uri(e.Request.Uri) != _localFileURI)
+                        await _browser.EnsureCoreWebView2Async(_webView2Environment).ConfigureAwait(true);
+                        _browser.CoreWebView2.SetVirtualHostNameToFolderMapping(VirtualHostName, AssemblyDirectory, CoreWebView2HostResourceAccessKind.Deny);
+                        _browser.CoreWebView2.Settings.AreDefaultScriptDialogsEnabled = false;
+                        _browser.CoreWebView2.Settings.AreDefaultContextMenusEnabled = false;
+                        _browser.CoreWebView2.Settings.AreDevToolsEnabled = false;
+                        _browser.CoreWebView2.Settings.AreHostObjectsAllowed = false;
+                        _browser.CoreWebView2.Settings.IsGeneralAutofillEnabled = false;
+                        _browser.CoreWebView2.Settings.IsPasswordAutosaveEnabled = false;
+                        _browser.CoreWebView2.Settings.IsScriptEnabled = false;
+                        _browser.CoreWebView2.Settings.IsWebMessageEnabled = false;
+
+                        // Don't load any resources.
+                        _browser.CoreWebView2.AddWebResourceRequestedFilter("*", CoreWebView2WebResourceContext.All);
+                        _browser.CoreWebView2.WebResourceRequested += (object sender, CoreWebView2WebResourceRequestedEventArgs e) =>
                         {
-                            e.Response = _browser.CoreWebView2.Environment.CreateWebResourceResponse(null, 403, "Forbidden", null);
+                            // Show local file we've saved with the svg contents. Block all else.
+                            if (new Uri(e.Request.Uri) != _localFileURI)
+                            {
+                                e.Response = _browser.CoreWebView2.Environment.CreateWebResourceResponse(null, 403, "Forbidden", null);
+                            }
+                        };
+
+                        // WebView2.NavigateToString() limitation
+                        // See https://learn.microsoft.com/dotnet/api/microsoft.web.webview2.core.corewebview2.navigatetostring?view=webview2-dotnet-1.0.864.35#remarks
+                        // While testing the limit, it turned out it is ~1.5MB, so to be on a safe side we go for 1.5m bytes
+                        SvgContentsReady.Wait();
+                        if (string.IsNullOrEmpty(SvgContents) || !SvgContents.Contains("svg"))
+                        {
+                            thumbnailDone.Set();
+                            return;
                         }
-                    };
 
-                    // WebView2.NavigateToString() limitation
+                        if (SvgContents.Length > 1_500_000)
-                    // See https://learn.microsoft.com/dotnet/api/microsoft.web.webview2.core.corewebview2.navigatetostring?view=webview2-dotnet-1.0.864.35#remarks
+                        {
-                    // While testing the limit, it turned out it is ~1.5MB, so to be on a safe side we go for 1.5m bytes
+                            string filename = _webView2UserDataFolder + "\\" + Guid.NewGuid().ToString() + ".html";
-                    SvgContentsReady.Wait();
+                            File.WriteAllText(filename, SvgContents);
-                    if (string.IsNullOrEmpty(SvgContents) || !SvgContents.Contains("svg"))
+                            _localFileURI = new Uri(filename);
-                    {
+                            _browser.Source = _localFileURI;
-                        thumbnailDone.Set();
+                        }
-                        return;
+                        else
-                    }
+                        {
+                            _browser.NavigateToString(SvgContents);
+                        }
 
-                    if (SvgContents.Length > 1_500_000)
+                        break; // Exit the retry loop if initialization succeeds
-                    {
-                        string filename = _webView2UserDataFolder + "\\" + Guid.NewGuid().ToString() + ".html";
-                        File.WriteAllText(filename, SvgContents);
-                        _localFileURI = new Uri(filename);
-                        _browser.Source = _localFileURI;
                     }
-                    else
+                    catch (Exception ex)
                     {
-                        _browser.NavigateToString(SvgContents);
+                        Logger.LogError($"Initialization attempt {attempt} failed: {ex.Message}");
+                        if (attempt == 2)
+                        {
+                            Logger.LogError($"Failed running webView2Environment completed for {FilePath} : ", ex);
+                            thumbnailDone.Set();
+                            return;
+                        }
+
+                        await Task.Delay(1000); // Delay before retrying
                     }
                 }
-                catch (Exception ex)
-                {
-                    Logger.LogError($"Failed running webView2Environment completed for {FilePath} : ", ex);
-                    thumbnailDone.Set();
-                }
             });
 
             while (!thumbnailDone.Wait(75))