private async Task Decrypt(FileInfo file, FileInfo key, IProgress <long> progress, CancellationToken token)
{
RSA.RSAKeyPair?decryptKey = null;
DecryptMessage = "키 불러오는 중...";
await Task.Delay(500);
using (var fs = key.OpenRead())
{
BinaryFormatter bf = new BinaryFormatter();
decryptKey = bf.Deserialize(fs) as RSA.RSAKeyPair?;
}
string originalFileName;
if (!ExtractFileName(file.Name, out originalFileName))
{
DecryptMessage = "파일 이름이 올바르지 않습니다.";
await Task.Delay(500);
return;
}
string originalExtension = ExtractExtension(originalFileName);
if (decryptKey != null)
{
SaveFileDialog sfd = new SaveFileDialog();
sfd.FileName = originalFileName;
if (!string.IsNullOrWhiteSpace(originalExtension))
{
sfd.Filter = $"Original File|*.{originalExtension}";
}
if (sfd.ShowDialog() ?? false)
{
Queue <byte> buffer = new Queue <byte>();
saveFilePath = sfd.FileName;
DecryptMessage = "키 불러오기 완료.";
await Task.Delay(500);
RSA.RSAKeyPair keyPair = decryptKey.Value;
State = RSA.EncryptionState.CreateMap;
MaxProgress = 255;
var map = await Decrypter.CreateByteMap(keyPair, progress);
var updateTick = EncryptViewModel.GetUpdateTick(EncryptedFileLength);
State = RSA.EncryptionState.ConvertByte;
MaxProgress = EncryptedFileLength;
await Task.Delay(500);
using (var inStream = file.OpenRead())
{
using (var reader = new BinaryReader(inStream))
{
using (var outStream = File.OpenWrite(saveFilePath))
{
using (var writer = new BinaryWriter(outStream))
{
timeHelper.Reset(EncryptedFileLength);
for (long i = 0; i < EncryptedFileLength; i++)
{
token.ThrowIfCancellationRequested();
byte b = reader.ReadByte();
buffer.Enqueue(map[b]);
if (i % updateTick == 0)
{
while (buffer.Count > 0)
{
writer.Write(buffer.Dequeue());
}
progress.Report(i);
buffer.Clear();
await Task.Delay(1);
}
}
while (buffer.Count > 0)
{
writer.Write(buffer.Dequeue());
}
progress.Report(EncryptedFileLength);
}
}
}
}
DecryptMessage = "작업이 완료 되었습니다.";
var now = DateTime.Now;
Completed?.Invoke("작업 완료", $"완료 시간 : {now}\n걸린 시간 : {(now - timeHelper.StartTime).TotalSeconds} 초");
}
else
{
DecryptMessage = "사용자가 작업을 취소했습니다.";
}
}
else
{
DecryptMessage = "키가 잘못된 듯 합니다.";
}
await Task.Delay(500);
}