Files
PowerToys/src/modules/previewpane/SvgPreviewHandler/SvgPreviewControl.cs

339 lines
13 KiB
C#

// Copyright (c) Microsoft Corporation
// The Microsoft Corporation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
using System.Net.Http;
using System.Reflection;
using System.Runtime.CompilerServices;
using Common;
using Common.Utilities;
using Microsoft.PowerToys.PreviewHandler.Svg.Telemetry.Events;
using Microsoft.PowerToys.Telemetry;
using Microsoft.Web.WebView2.Core;
using Microsoft.Web.WebView2.WinForms;
using SvgPreviewHandler;
namespace Microsoft.PowerToys.PreviewHandler.Svg
{
/// <summary>
/// Implementation of Control for Svg Preview Handler.
/// </summary>
public class SvgPreviewControl : FormHandlerControl
{
/// <summary>
/// Settings class
/// </summary>
private readonly SvgPreviewHandler.Settings _settings = new();
/// <summary>
/// Generator for the actual preview file
/// </summary>
private readonly SvgHTMLPreviewGenerator _previewGenerator = new();
/// <summary>
/// WebView2 Control to display Svg.
/// </summary>
private WebView2 _browser;
/// <summary>
/// WebView2 Environment
/// </summary>
private CoreWebView2Environment _webView2Environment;
/// <summary>
/// Name of the virtual host
/// </summary>
private const string VirtualHostName = "PowerToysLocalSvg";
/// <summary>
/// URI of the local file saved with the contents
/// </summary>
private Uri _localFileURI;
/// <summary>
/// Gets the path of the current assembly.
/// </summary>
/// <remarks>
/// Source: https://stackoverflow.com/a/283917/14774889
/// </remarks>
private static string AssemblyDirectory
{
get
{
string codeBase = Assembly.GetExecutingAssembly().Location;
UriBuilder uri = new UriBuilder(codeBase);
string path = Uri.UnescapeDataString(uri.Path);
return Path.GetDirectoryName(path);
}
}
/// <summary>
/// Text box to display the information about blocked elements from Svg.
/// </summary>
private RichTextBox _textBox;
/// <summary>
/// Represent if an text box info bar is added for showing message.
/// </summary>
private bool _infoBarAdded;
/// <summary>
/// Represent WebView2 user data folder path.
/// </summary>
private string _webView2UserDataFolder = System.Environment.GetEnvironmentVariable("USERPROFILE") +
"\\AppData\\LocalLow\\Microsoft\\PowerToys\\SvgPreview-Temp";
public SvgPreviewControl()
{
this.SetBackgroundColor(_settings.ThemeColor);
}
/// <summary>
/// Start the preview on the Control.
/// </summary>
/// <param name="dataSource">Stream reference to access source file.</param>
public override void DoPreview<T>(T dataSource)
{
if (global::PowerToys.GPOWrapper.GPOWrapper.GetConfiguredSvgPreviewEnabledValue() == global::PowerToys.GPOWrapper.GpoRuleConfigured.Disabled)
{
// GPO is disabling this utility. Show an error message instead.
_infoBarAdded = true;
AddTextBoxControl(Properties.Resource.GpoDisabledErrorText);
Resize += FormResized;
base.DoPreview(dataSource);
return;
}
CleanupWebView2UserDataFolder();
string svgData = null;
bool blocked = false;
try
{
if (!(dataSource is string filePath))
{
throw new ArgumentException($"{nameof(dataSource)} for {nameof(SvgPreviewControl)} must be a string but was a '{typeof(T)}'");
}
using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
using (var reader = new StreamReader(stream))
{
svgData = reader.ReadToEnd();
}
}
blocked = SvgPreviewHandlerHelper.CheckBlockedElements(svgData);
}
catch (Exception ex)
{
PreviewError(ex, dataSource);
return;
}
try
{
// Fixes #17527 - Inkscape v1.1 swapped order of default and svg namespaces in svg file (default first, svg after).
// That resulted in parser being unable to parse it correctly and instead of svg, text was previewed.
// MS Edge and Firefox also couldn't preview svg files with mentioned order of namespaces definitions.
svgData = SvgPreviewHandlerHelper.SwapNamespaces(svgData);
svgData = SvgPreviewHandlerHelper.AddStyleSVG(svgData);
}
catch (Exception ex)
{
try
{
PowerToysTelemetry.Log.WriteEvent(new SvgFilePreviewError { Message = ex.Message });
}
catch
{ // Should not crash if sending telemetry is failing. Ignore the exception.
}
}
try
{
_infoBarAdded = false;
// Add a info bar on top of the Preview if any blocked element is present.
if (blocked)
{
_infoBarAdded = true;
AddTextBoxControl(Properties.Resource.BlockedElementInfoText);
}
AddWebViewControl(svgData);
Resize += FormResized;
base.DoPreview(dataSource);
try
{
PowerToysTelemetry.Log.WriteEvent(new SvgFilePreviewed());
}
catch
{ // Should not crash if sending telemetry is failing. Ignore the exception.
}
}
catch (Exception ex)
{
PreviewError(ex, dataSource);
}
}
/// <summary>
/// Occurs when RichtextBox is resized.
/// </summary>
/// <param name="sender">Reference to resized control.</param>
/// <param name="e">Provides data for the ContentsResized event.</param>
private void RTBContentsResized(object sender, ContentsResizedEventArgs e)
{
var richTextBox = sender as RichTextBox;
richTextBox.Height = e.NewRectangle.Height + 5;
}
/// <summary>
/// Occurs when form is resized.
/// </summary>
/// <param name="sender">Reference to resized control.</param>
/// <param name="e">Provides data for the resize event.</param>
private void FormResized(object sender, EventArgs e)
{
if (_infoBarAdded)
{
_textBox.Width = Width;
}
}
// Disable loading resources.
private void CoreWebView2_BlockExternalResources(object sender, CoreWebView2WebResourceRequestedEventArgs e)
{
// 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);
}
}
/// <summary>
/// Adds a WebView2 Control to Control Collection.
/// </summary>
/// <param name="svgData">Svg to display on Browser Control.</param>
private void AddWebViewControl(string svgData)
{
_browser = new WebView2();
_browser.DefaultBackgroundColor = Color.Transparent;
_browser.Dock = DockStyle.Fill;
// Prevent new windows from being opened.
var webView2Options = new CoreWebView2EnvironmentOptions("--block-new-web-contents");
ConfiguredTaskAwaitable<CoreWebView2Environment>.ConfiguredTaskAwaiter
webView2EnvironmentAwaiter = CoreWebView2Environment
.CreateAsync(userDataFolder: _webView2UserDataFolder, options: webView2Options)
.ConfigureAwait(true).GetAwaiter();
webView2EnvironmentAwaiter.OnCompleted(async () =>
{
try
{
_webView2Environment = webView2EnvironmentAwaiter.GetResult();
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 += CoreWebView2_BlockExternalResources;
string generatedPreview = _previewGenerator.GeneratePreview(svgData);
// 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
if (generatedPreview.Length > 1_500_000)
{
string filename = _webView2UserDataFolder + "\\" + Guid.NewGuid().ToString() + ".html";
File.WriteAllText(filename, generatedPreview);
_localFileURI = new Uri(filename);
_browser.Source = _localFileURI;
}
else
{
_browser.NavigateToString(generatedPreview);
}
Controls.Add(_browser);
}
catch (Exception)
{
}
});
}
/// <summary>
/// Adds a Text Box in Controls for showing information about blocked elements.
/// </summary>
/// <param name="message">Message to be displayed in textbox.</param>
private void AddTextBoxControl(string message)
{
_textBox = new RichTextBox();
_textBox.Text = message;
_textBox.BackColor = Color.LightYellow;
_textBox.Multiline = true;
_textBox.Dock = DockStyle.Top;
_textBox.ReadOnly = true;
_textBox.ContentsResized += RTBContentsResized;
_textBox.ScrollBars = RichTextBoxScrollBars.None;
_textBox.BorderStyle = BorderStyle.None;
Controls.Add(_textBox);
}
/// <summary>
/// Called when an error occurs during preview.
/// </summary>
/// <param name="exception">The exception which occurred.</param>
/// <param name="dataSource">Stream reference to access source file.</param>
private void PreviewError<T>(Exception exception, T dataSource)
{
try
{
PowerToysTelemetry.Log.WriteEvent(new SvgFilePreviewError { Message = exception.Message });
}
catch
{ // Should not crash if sending telemetry is failing. Ignore the exception.
}
Controls.Clear();
_infoBarAdded = true;
AddTextBoxControl(Properties.Resource.SvgNotPreviewedError);
base.DoPreview(dataSource);
}
/// <summary>
/// Cleanup the previously created tmp html files from svg files bigger than 2MB.
/// </summary>
private void CleanupWebView2UserDataFolder()
{
try
{
// Cleanup temp dir
var dir = new DirectoryInfo(_webView2UserDataFolder);
foreach (var file in dir.EnumerateFiles("*.html"))
{
file.Delete();
}
}
catch (Exception)
{
}
}
}
}