public bool TryRemove(T record, int index, out T removedRecord)
{
_workingBlock = new Block <T>(MaxRecords);
_workingBlock.FromByteArray(_file.ReadData(index));
removedRecord = default(T);
if (_workingBlock.TryRemoveRecord(record, out removedRecord))
{
if (_workingBlock.ValidCount == 0)
{
_partiallyFullBlocks.Remove(index);
_freeBlocks.Add(index);
_file.AdjustFileSize(_freeBlocks);
}
else
{
if (!_partiallyFullBlocks.Contains(index))
{
_partiallyFullBlocks.Add(index);
}
_file.WriteData(index, _workingBlock.ToByteArray());
}
return(true);
}
return(false);
}
private void AdjustFile()
{
_blockFile.AdjustFileSize(_freeBlocks);
}
private bool TryRemoveOverflow(ExternalTrieNode node, T record, out T removedRecord, out bool canDoJoin)
{
//najskor pozriet do seba ci nemam node
//ak nie
//nacitat vsetky ostatne (ak mam)
//najst a vymazat
//skusit utriast
removedRecord = default(T);
canDoJoin = false;
_workingBlock1 = new Block <T>(MaxRecords);
_workingBlock1.FromByteArray(_blockFile.ReadData(node.IndexOfBlock));
var listOverflowBlocks = new List <Block <T> >();
var index = _workingBlock1.NextOverflowBlockIndex;
if (index == -1)
{
throw new Exception($"This should not happened, index of block: {node.IndexOfBlock} and should NOT be -1");
}
while (index != -1) //nacitam vsetky preplnene
{
listOverflowBlocks.Add(new Block <T>(MaxRecordsInOverflow));
listOverflowBlocks[listOverflowBlocks.Count - 1].FromByteArray(_overflowFile.ReadData(index));
index = listOverflowBlocks[listOverflowBlocks.Count - 1].NextOverflowBlockIndex;
}
var currentCount = node.RecordCount;
if (_workingBlock1.TryRemoveRecord(record, out removedRecord))
{
node.RecordCount--;
}
else
{
foreach (var block in listOverflowBlocks)
{
if (block.TryRemoveRecord(record, out removedRecord))
{
node.RecordCount--;
break;
}
}
}
if (currentCount == node.RecordCount)
{
return(false); //nepodarilo sa vymazat
}
if ((MaxRecords + listOverflowBlocks.Count * MaxRecordsInOverflow) - node.RecordCount ==
MaxRecordsInOverflow)
{
//ideme utriasat
var lastBlock = listOverflowBlocks[listOverflowBlocks.Count - 1];
listOverflowBlocks.RemoveAt(listOverflowBlocks.Count - 1);
if (listOverflowBlocks.Count > 0)
{
_freeBlocksOverflow.Add(listOverflowBlocks[listOverflowBlocks.Count - 1].NextOverflowBlockIndex);
listOverflowBlocks[listOverflowBlocks.Count - 1].NextOverflowBlockIndex = -1;
}
else
{
_freeBlocksOverflow.Add(_workingBlock1.NextOverflowBlockIndex);
_workingBlock1.NextOverflowBlockIndex = -1;
}
_overflowFile.AdjustFileSize(_freeBlocksOverflow);
var helpCounter = 0;
foreach (var rec in lastBlock.GetAllRecords())
{
if (_workingBlock1.AddRecord(rec))
{
helpCounter++;
continue;
}
foreach (var blockInList in listOverflowBlocks)
{
if (blockInList.AddRecord(rec))
{
helpCounter++;
break;
}
}
}
if (helpCounter != lastBlock.ValidCount)
{
throw new Exception($"This should not happened, not all blocks were added");
}
//mame utrasene mozme zapisat
}
for (int i = listOverflowBlocks.Count - 1; i > 0; i--)
{
_overflowFile.WriteData(listOverflowBlocks[i - 1].NextOverflowBlockIndex,
listOverflowBlocks[i].ToByteArray()); //kazdeho zapisem podla indexu predchadzajuceho (az na prveho)
}
if (listOverflowBlocks.Count > 0)
{
_overflowFile.WriteData(_workingBlock1.NextOverflowBlockIndex, listOverflowBlocks[0].ToByteArray());
}
canDoJoin = CanJoinNodes(node, node.RecordCount);
if (!canDoJoin) //zapisem povodny blok len ak uz sa nejde s nim hybat
{
_blockFile.WriteData(node.IndexOfBlock, _workingBlock1.ToByteArray());
}
if (node.RecordCount < MaxRecords)
{
throw new Exception($"This should not happened, record count < _maxrecords during overflow deleting");
}
return(true);
}
