private static async Task <HashSet <string> > GetAssets(CancellationToken ct)
{
var assetsUri = AssetsPathBuilder.BuildAssetUri("uno-assets.txt");
var assets = await WebAssemblyRuntime.InvokeAsync($"Windows.Storage.AssetManager.DownloadAssetsManifest(\'{assetsUri}\')");
return(new HashSet <string>(Regex.Split(assets, "\r\n|\r|\n"), StringComparer.OrdinalIgnoreCase));
}
public static async Task <string> DownloadAsset(CancellationToken ct, string assetPath)
{
var updatedPath = assetPath.TrimStart("/");
var assetSet = await _assets.Value;
if (assetSet.Contains(updatedPath))
{
var localPath = Path.Combine(Windows.Storage.ApplicationData.Current.LocalFolder.Path, ".assetsCache", AssetsPathBuilder.UNO_BOOTSTRAP_APP_BASE, updatedPath);
using var assetLock = await _assetsGate.LockForAsset(ct, updatedPath);
if (!File.Exists(localPath))
{
var assetUri = AssetsPathBuilder.BuildAssetUri(updatedPath);
var assetInfo = await WebAssemblyRuntime.InvokeAsync($"Windows.Storage.AssetManager.DownloadAsset(\'{assetUri}\')");
var parts = assetInfo.Split(';');
if (parts.Length == 2)
{
var ptr = (IntPtr)int.Parse(parts[0], CultureInfo.InvariantCulture);
var length = int.Parse(parts[1], CultureInfo.InvariantCulture);
try
{
var buffer = new byte[length];
Marshal.Copy(ptr, buffer, 0, length);
if (Path.GetDirectoryName(localPath) is { } path)
{
Directory.CreateDirectory(path);
}
File.WriteAllBytes(localPath, buffer);
}
finally
{
Marshal.FreeHGlobal(ptr);
}
}
else
{
throw new InvalidOperationException($"Invalid Windows.Storage.AssetManager.DownloadAsset return value");
}
}
return(localPath);
}
else
{
throw new FileNotFoundException($"The file [{assetPath}] cannot be found");
}
}