private void Download(System.ComponentModel.DoWorkEventArgs e)
{
// Initializing service proxy
var cloudProxy = new CloudServiceClient();
try
{
// Initializing client-side decryption
var clientCypher = new XTEA();
// Getting decryption key
clientCypher.SetKey(Encoding.ASCII.GetBytes(cloudProxy.GetKey()));
// Initializing stream from service
var length = cloudProxy.DownloadFile(ref _cloudFileName, out var inputStream);
// Write stream to disk
using (var writeStream = new FileStream(_localFilePath, FileMode.CreateNew, FileAccess.Write))
{
// Initializing buffer
var buffer = new byte[ChunkSize];
// Initializing boolean determining whether it's the last chunk
var lastChunk = false;
do
{
// Read bytes from input stream
var bytesRead = inputStream.Read(buffer, 0, ChunkSize);
if (bytesRead == 0)
{
break;
}
// Check if it is the last chunk
if (bytesRead < ChunkSize)
{
var temp = new byte[bytesRead];
Array.Copy(buffer, temp, bytesRead);
buffer = temp;
lastChunk = true;
}
// Decrypt data from the buffer
var decryptedBuffer = clientCypher.Decrypt(buffer);
// Write bytes to output stream
writeStream.Write(decryptedBuffer, 0, decryptedBuffer.Length);
// Update progress bar
if (lastChunk)
{
backgroundWorker.ReportProgress(100);
}
else
{
backgroundWorker.ReportProgress((int)(writeStream.Position * 100 / length));
}
// Check for cancellation
if (!backgroundWorker.CancellationPending)
{
continue;
}
e.Cancel = true;
inputStream.Dispose();
return;
} while (!lastChunk);
writeStream.Close();
}
// Deallocate stream
inputStream.Dispose();
}
catch (Exception exception)
{
throw new ArgumentException(exception.Message);
}
finally
{
// Close service proxy
cloudProxy.Close();
}
}