public BaseSnapObject MakeCopy()
{
var item = SnapObjectsInfo.GetInstanceByType(Type);
item.Deserialize(Serialize(), 0);
return(item);
}
public static Snapshot UnpackDelta(Snapshot from, int[] inputData,
int inputOffset, int inputSize)
{
var snapshotBuilder = new SnapshotBuilder();
var endIndex = inputOffset + inputSize;
var numDeletedItems = inputData[inputOffset++];
var numUpdatedItems = inputData[inputOffset++];
var numTempItems = inputData[inputOffset++];
var deletedOffset = inputOffset;
inputOffset += numDeletedItems;
if (inputOffset > endIndex)
{
return(null);
}
snapshotBuilder.StartBuild();
for (var i = 0; i < from.ItemsCount; i++)
{
var item = from[i];
var keep = true;
for (var d = 0; d < numDeletedItems; d++)
{
if (inputData[deletedOffset + d] == item.Key)
{
keep = false;
break;
}
}
if (keep)
{
snapshotBuilder.AddItem(item.Object.MakeCopy(), item.Id);
}
}
for (var i = 0; i < numUpdatedItems; i++)
{
if (inputOffset + 2 > endIndex)
{
return(null);
}
var type = (SnapObject)inputData[inputOffset++];
var id = inputData[inputOffset++];
int itemSize; // in bytes
if (SnapObjectsInfo.GetSizeByType(type) != 0)
{
itemSize = SnapObjectsInfo.GetSizeByType(type);
}
else
{
if (inputOffset + 1 > endIndex)
{
return(null);
}
itemSize = inputData[inputOffset++] * sizeof(int);
}
if (itemSize < 0 || !RangeCheck(endIndex, inputOffset, itemSize / sizeof(int)))
{
return(null);
}
var key = ((int)type << 16) | id;
var newItem = snapshotBuilder.FindItem(key)?.Object;
if (newItem == null)
{
var item = SnapObjectsInfo.GetInstanceByType(type);
if (snapshotBuilder.AddItem(item, id))
{
newItem = item;
}
}
if (newItem == null)
{
return(null);
}
var fromItem = from.FindItem(key);
if (fromItem != null)
{
UndiffItem(fromItem.Object, inputData, inputOffset, newItem);
}
else
{
newItem.Deserialize(inputData, inputOffset);
}
inputOffset += itemSize / sizeof(int);
}
return(snapshotBuilder.EndBuild());
}