/// <summary>
/// Decopmpress of the block if PC has RAM less than block size
/// </summary>
/// <param name="id">block id</param>
/// <param name="blockSize"> block size in bytes</param>
/// <param name="sizeFreeMemory"> size of free RAM</param>
/// <param name="deCompressionStream">stream</param>
private void DecompressFileInBlocksOnMaxRamMemory(int id, long blockSize, long sizeFreeMemory, GZipStream deCompressionStream)
{
while (blockSize > 0)
{
if (blockSize > sizeFreeMemory)
{
blockSize = blockSize - sizeFreeMemory;
}
else
{
sizeFreeMemory = blockSize;
blockSize = 0;
}
var bytes = new LargeByteArray(sizeFreeMemory);
ReadingDecompressedStreamInByte(bytes, deCompressionStream);
#if DEBUG
Console.WriteLine($"Read the block id:{id} size:{sizeFreeMemory / 1024} KB");
#endif
lock (_blocks)
{
_blocks.Enqueue(new Block(id, bytes, sizeFreeMemory));
}
if (_threadWDec.IsAlive == false)
{
_threadWDec.Start();
}
sizeFreeMemory = GetSizeFreeMemory();
}
}
/// <summary>
/// Reading from stream to bytes array of datas
/// </summary>
/// <param name="bytes">big bytes array</param>
/// <param name="deCompressionStream">stream</param>
private void ReadingDecompressedStreamInByte(LargeByteArray bytes, GZipStream deCompressionStream)
{
for (int i = 0; i < bytes.CountOfArray; i++)
{
int count = deCompressionStream.Read(bytes[i], 0, bytes[i].Length);
bytes.CountOfByte[i] = count;
}
}
/// <summary>
/// Reading from stream to bytes array of datas
/// </summary>
/// <param name="bytes">bytes array for reading</param>
/// <param name="fs">stream</param>
/// <returns> count read bytes </returns>
private static long ReadingStreamInByte(LargeByteArray bytes, FileStream fs)
{
long countReadingByte = 0;
for (int i = 0; i < bytes.CountOfArray; ++i)
{
int count = fs.Read(bytes[i], 0, bytes[i].Length);
bytes.CountOfByte[i] = count;
countReadingByte += count;
}
return(countReadingByte);
}
/// <summary>
/// Function of Decompressing
/// </summary>
/// <param name="compressedFile">compressed file</param>
/// <param name="deCompressedFile">decompressed file</param>
public void Decompress(string compressedFile, string deCompressedFile)
{
FileIsExist(compressedFile);
_compressedFile = compressedFile;
_deCompressedFile = deCompressedFile;
using (var compressFs = new FileStream(_compressedFile, FileMode.OpenOrCreate, FileAccess.Read))
{
using (var deCompressionStream = new GZipStream(compressFs, CompressionMode.Decompress))
{
_finish = false;
_threadWDec = new Thread(WritingOfDecompressedBlock);
var(id, blockSize) = GetIdAndSizeOfBlock(deCompressionStream);
while (blockSize > 0)
{
var sizeFreeMemory = GetSizeFreeMemory();
if (blockSize > sizeFreeMemory)
{
DecompressFileInBlocksOnMaxRamMemory(id, blockSize, sizeFreeMemory, deCompressionStream);
}
else
{
var bytes = new LargeByteArray(blockSize);
ReadingDecompressedStreamInByte(bytes, deCompressionStream);
lock (_blocks)
{
_blocks.Enqueue(new Block(id, bytes, blockSize));
}
#if DEBUG
Console.WriteLine($"Read the block id:{id} size:{blockSize / 1024} KB");
#endif
if (_threadWDec.IsAlive == false)
{
_threadWDec.Start();
}
}
(id, blockSize) = GetIdAndSizeOfBlock(deCompressionStream);
}
_finish = true;
EndReadingWaitHandler.WaitOne();
}
}
#if DEBUG
Console.WriteLine("Decompressed successfully");
#endif
}
/// <summary>
/// Function of compressing
/// </summary>
/// <param name="sourceFile">source file</param>
/// <param name="compressedFile">compressed file </param>
public void Compress(string sourceFile, string compressedFile)
{
FileIsExist(sourceFile);
_sourceFile = sourceFile;
_compressedFile = $"{compressedFile}.gz";
using (var fs = new FileStream(_sourceFile, FileMode.Open))
{
var id = 0;
_finish = false;
var threadW = new Thread(WritingOfBlockCompress);
long sizeFreeMemory = GetSizeFreeMemory();
var bytes = new LargeByteArray(sizeFreeMemory);
long countReadingByte = ReadingStreamInByte(bytes, fs);
while (countReadingByte > 0)
{
#if DEBUG
Console.WriteLine($"Read the block: id:{id} size:{countReadingByte / 1024} KB");
#endif
lock (_blocks)
{
_blocks.Enqueue(new Block(id++, bytes, countReadingByte));
}
if (threadW.IsAlive == false)
{
threadW.Start();
}
sizeFreeMemory = GetSizeFreeMemory();
bytes = new LargeByteArray(sizeFreeMemory);
countReadingByte = ReadingStreamInByte(bytes, fs);
}
_finish = true;
EndReadingWaitHandler.WaitOne();
}
#if DEBUG
Console.WriteLine("Сompressed successfully");
#endif
}
