/// <summary>
/// Gets a block from the cache at the specified index.
/// </summary>
/// <param name="index">The zero-based index of the block.</param>
/// <returns>The cached sequence block.</returns>
private CacheBox <byte[]> GetCacheBlock(int index)
{
CacheBox <byte[]> block = _virtualData.FirstOrDefault(C => index >= C.StartRange && index <= C.EndRange);
if (block != null)
{
return(block);
}
else
{
int startIndex = index - (index % BlockSize);
byte[] seq = _parser.ParseRange(startIndex, BlockSize, SequencePointerInstance);
if (seq == null)
{
return(null);
}
else
{
block = new CacheBox <byte[]>(seq.Length)
{
StartRange = startIndex
};
block.EndRange = block.StartRange + seq.Length - 1;
block.Data = seq;
_virtualData.Add(block);
return(block);
}
}
}
/// <summary>
/// Gets a block from the cache at the specified index.
/// </summary>
/// <param name="index">The zero-based index of the block.</param>
/// <returns>The cached sequence block.</returns>
private CacheBox <byte[]> GetCacheBlock(int index)
{
CacheBox <byte[]> block = _virtualData.FirstOrDefault(C => index >= C.StartRange && index <= C.EndRange);
if (block != null)
{
return(block);
}
else
{
int startIndex = index;
int blockStartingIndex = index - (index % BlockSize);
int sequenceLength = (int)(SequencePointerInstance.IndexOffsets[1] - SequencePointerInstance.IndexOffsets[0]);
int count = sequenceLength > BlockSize ? BlockSize : sequenceLength;
if (sequenceLength > BlockSize && _sidecarProvider != null)
{
blockStartingIndex = _sidecarProvider.GetBlockToLoad(_sequenceIndex, index, ref startIndex, ref count);
}
else
{
blockStartingIndex = 0;
startIndex = 0;
}
byte[] seq = _parser.ParseRange(blockStartingIndex, count, SequencePointerInstance);
if (seq == null)
{
return(null);
}
else
{
block = new CacheBox <byte[]>(seq.Length)
{
StartRange = startIndex
};
block.EndRange = block.StartRange + seq.Length - 1;
block.Data = seq;
_virtualData.Add(block);
return(block);
}
}
}