private void WriteCompressionToFile(string filePath, CompressionMetaData metaData, out long fileSize, out bool isSuccess)
{
using var fileStream = _fileService.Create(filePath);
fileStream.Seek(metaData.MetaDataSize, SeekOrigin.Begin);
isSuccess = WriteBlocksToStream(fileStream, metaData.BlockSizes.Length);
_metaDataService.WriteToStream(fileStream, metaData);
fileSize = fileStream.Length;
}
public void WriteToStream(Stream stream, CompressionMetaData metaData)
{
stream.Seek(0, SeekOrigin.Begin);
using var binaryWriter = new BinaryWriter(stream, Encoding.UTF8, true);
binaryWriter.Write(metaData.BlockSizes.Length);
foreach (var blockSize in metaData.BlockSizes)
{
binaryWriter.Write(blockSize);
}
}
public CompressionMetaData ReadFromStream(Stream stream)
{
using var binaryReader = new BinaryReader(stream, Encoding.UTF8, true);
CheckBytesExist(stream, 4);
var metaData = new CompressionMetaData(binaryReader.ReadInt32());
CheckBytesExist(stream, (long)4 * metaData.BlockSizes.Length);
for (int i = 0; i < metaData.BlockSizes.Length; i++)
{
var value = binaryReader.ReadInt32();
if (value < 1)
{
throw new InvalidDataException(CompressionExceptionMessages.WrongFormat);
}
metaData.BlockSizes[i] = value;
}
return(metaData);
}
public CompressionResult Compress(string inputFilePath, string outputFilePath)
{
using var inputFileStream = _fileService.OpenRead(inputFilePath);
var blockCount = Math.Ceiling((double)inputFileStream.Length / BlockSize);
if (blockCount > MaxBlockSize)
{
throw new InvalidDataException(CompressionExceptionMessages.TooManyBlocks);
}
var metaData = new CompressionMetaData((int)blockCount);
long outputFileSize = 0;
bool isSuccess = false;
var writerThread =
_threadPool.RunDedicated(() => WriteCompressionToFile(outputFilePath, metaData, out outputFileSize, out isSuccess));
for (int i = 0; i < metaData.BlockSizes.Length; i++)
{
var blockIndex = i;
var blockBytes = ReadBlockFromStream(inputFileStream, BlockSize);
_threadPool.Run(() =>
ProcessBlock(blockBytes, blockIndex, _compressService.Compress, metaData.BlockSizes));
}
writerThread.Join();
if (!isSuccess)
{
throw new InvalidDataException(CompressionExceptionMessages.UnknownCompressException);
}
return(new CompressionResult(inputFileStream.Length, outputFileSize)
{
MetaData = metaData
});
}
private void WriteDecompressionToFile(string filePath, CompressionMetaData metaData, out long fileSize, out bool isSuccess)
{
using var fileStream = _fileService.Create(filePath);
isSuccess = WriteBlocksToStream(fileStream, metaData.BlockSizes.Length);
fileSize = fileStream.Length;
}
