private void HandleFileDownload(NetworkStream networkStream)
{
// Get client download file header
var clientHeader = GetClientDownloadFileHeader(networkStream);
// Check file availability
var query = FileDB.FileEntries.Where(f => f.Name == clientHeader.Filename);
if (query.Count() < 1 || query.First().ToBeDeleted)
{
var negativeResponseBytes = BitConverter.GetBytes((int)ResponeType.Failure);
networkStream.Write(negativeResponseBytes, 0, negativeResponseBytes.Length);
return;
}
else
{
++query.First().CurrentUses;
var positiveResponseBytes = BitConverter.GetBytes((int)ResponeType.Success);
networkStream.Write(positiveResponseBytes, 0, positiveResponseBytes.Length);
}
int fileSize = FileDB.GetFileLength(clientHeader.Filename);
int numBlocks = fileSize / BlockSize;
int lastBlockSize = fileSize % BlockSize;
var serverHeader = new ServerDownloadFileHeader()
{
FileSize = fileSize,
NumBlocks = numBlocks,
LastBlockSize = lastBlockSize
};
var serverHeaderBytes = SerializationMethods.Serialize(serverHeader);
var serverHeaderLengthBytes = BitConverter.GetBytes(serverHeaderBytes.Length);
networkStream.Write(serverHeaderLengthBytes, 0, serverHeaderLengthBytes.Length);
networkStream.Write(serverHeaderBytes, 0, serverHeaderBytes.Length);
var downloadSession = new FileDownloadSession(FileDB, clientHeader.Filename);
for (int i = 0; i < numBlocks; i++)
{
var fileData = FileDB.GetFileDataAtV2(downloadSession, i * BlockSize, (i + 1) * BlockSize - 1);
networkStream.Write(fileData, 0, fileData.Length);
}
if (lastBlockSize > 0)
{
var file_data = FileDB.GetFileDataAtV2(downloadSession, numBlocks * BlockSize, fileSize - 1);
networkStream.Write(file_data, 0, file_data.Length);
}
downloadSession.TerminateSession();
--query.First().CurrentUses;
}
