public static bool ValidateChain(ChainItem chainItem)
{
if (chainItem.PreviousItem != null)
{
if (!ValidateChain(chainItem.PreviousItem) || !chainItem.PreviousItem.IsApplicable(chainItem))
{
return(false);
}
}
var hash = chainItem.ComputeHash();
return(Enumerable.SequenceEqual(chainItem.Hash, hash));
}
public static bool IsTheSameChainItems(ChainItem chainItem1, ChainItem chainItem2)
{
if (chainItem1 == null)
{
throw new ArgumentNullException("chainItem1");
}
if (chainItem2 == null)
{
throw new ArgumentNullException("chainItem2");
}
int offset = 0;
ChainItem parentItem = null;
ChainItem childItem = null;
if (chainItem1.Index == chainItem2.Index)
{
return(Enumerable.SequenceEqual(chainItem1.Hash, chainItem2.Hash));
}
else if (chainItem1.Index < chainItem2.Index)
{
offset = chainItem2.Index - chainItem1.Index;
childItem = chainItem1;
parentItem = chainItem2;
}
else if (chainItem1.Index > chainItem2.Index)
{
offset = chainItem1.Index - chainItem2.Index;
parentItem = chainItem1;
childItem = chainItem2;
}
while ((offset > 0) && parentItem != null)
{
parentItem = parentItem.PreviousItem;
offset--;
}
return(parentItem != null && IsTheSameChainItems(parentItem, childItem));
}
public ChainItem(ChainItem previousItem, string payload)
{
if (previousItem == null)
{
throw new ArgumentNullException("previousItem");
}
if (!ValidateChain(previousItem))
{
throw new ArgumentException("previousItem");
}
Index = previousItem.Index + 1;
PreviousItem = previousItem;
Payload = payload ?? string.Empty;
Hash = ComputeHash();
if (!PreviousItem.IsApplicable(this))
{
throw new InvalidOperationException("Текущий элемент не может быть добавлен к этой цепочке");
}
}
static void Main(string[] args)
{
var chain = new List <ChainItem>();
var root = new ChainItem("ROOT");
chain.Add(root);
var currentItem = root;
for (int i = 0; i < 100; i++)
{
currentItem = new ChainItem(currentItem, "Item " + i.ToString());
chain.Add(currentItem);
}
var branchItem = new ChainItem(chain[40], "Branch");
var r1 = ChainItem.IsTheSameChainItems(chain[23], chain[45]);
var r2 = ChainItem.IsTheSameChainItems(chain[23], chain[23]);
var r3 = ChainItem.IsTheSameChainItems(chain[56], chain[13]);
var r4 = ChainItem.IsTheSameChainItems(branchItem, chain[13]);
var r5 = ChainItem.IsTheSameChainItems(branchItem, chain[56]);
}
protected virtual bool IsApplicable(ChainItem nextChainItem)
{
return(true);
}
