Fix Windows Media Source bug with Packaged Apps (#2609)

* Fix media element in windows where playing resource mediasource does not work when running app as packaged.

* Remove Unused Code

* `dotnet format`

---------

Co-authored-by: Brandon Minnick <[email protected]>

Author: ne0rrmatrix

src/CommunityToolkit.Maui.MediaElement/Services/AppPackageService.windows.cs

@@ -0,0 +1,43 @@
+using Windows.ApplicationModel;
+
+namespace CommunityToolkit.Maui.Extensions;
+
+// Since MediaElement can't access .NET MAUI internals we have to copy this code here
+// https://github.com/dotnet/maui/blob/main/src/Essentials/src/AppInfo/AppInfo.uwp.cs
+static class AppPackageService
+{
+	static readonly Lazy<bool> isPackagedAppHolder = new(() =>
+	{
+		try
+		{
+			if (Package.Current is not null)
+			{
+				return true;
+			}
+		}
+		catch
+		{
+			// no-op
+		}
+
+		return false;
+	});
+
+	static readonly Lazy<string> fullAppPackageFilePathHolder = new(() =>
+	{
+		return IsPackagedApp
+			? Package.Current.InstalledLocation.Path
+			: AppContext.BaseDirectory;
+	});
+
+	/// <summary>
+	/// Gets if this app is a packaged app.
+	/// </summary>
+	public static bool IsPackagedApp => isPackagedAppHolder.Value;
+
+
+	/// <summary>
+	/// Gets full application path.
+	/// </summary>
+	public static string FullAppPackageFilePath => fullAppPackageFilePathHolder.Value;
+}

src/CommunityToolkit.Maui.MediaElement/Views/MediaManager.windows.cs

@@ -1,6 +1,7 @@
 using System.Diagnostics;
 using System.Numerics;
 using CommunityToolkit.Maui.Core.Primitives;
+using CommunityToolkit.Maui.Extensions;
 using CommunityToolkit.Maui.Views;
 using Microsoft.Extensions.Logging;
 using Microsoft.UI.Xaml.Controls;
@@ -301,7 +302,13 @@ protected virtual async partial ValueTask PlatformUpdateSource()
 		}
 		else if (MediaElement.Source is ResourceMediaSource resourceMediaSource)
 		{
-			string path = "ms-appx:///" + resourceMediaSource.Path;
+			if (string.IsNullOrWhiteSpace(resourceMediaSource.Path))
+			{
+				Logger.LogInformation("ResourceMediaSource Path is null or empty");
+				return;
+			}
+
+			string path = GetFullAppPackageFilePath(resourceMediaSource.Path);
 			if (!string.IsNullOrWhiteSpace(path))
 			{
 				Player.Source = WinMediaSource.CreateFromUri(new Uri(path));
@@ -352,6 +359,16 @@ protected virtual void Dispose(bool disposing)
 		}
 	}
 
+	static string GetFullAppPackageFilePath(in string filename)
+	{
+		ArgumentNullException.ThrowIfNull(filename);
+
+		var normalizedFilename = NormalizePath(filename);
+		return Path.Combine(AppPackageService.FullAppPackageFilePath, normalizedFilename);
+
+		static string NormalizePath(string filename) => filename.Replace('\\', Path.DirectorySeparatorChar).Replace('/', Path.DirectorySeparatorChar);
+	}
+
 	static bool IsZero<TValue>(TValue numericValue) where TValue : INumber<TValue>
 	{
 		return TValue.IsZero(numericValue);