public string ToDotNotation(TrieOrder order)
{
var text = new StringBuilder();
text.AppendLine("digraph g {");
text.AppendLine("node[shape = circle];");
var labels = new Dictionary <INode, int>();
// Nodes
labels.Add(root, 1);
text.AppendLine($"node1[label=\"root\"]");
foreach (var childLink in GetChildrenFromNode(root, order))
{
int childIndex = 0;
if (!labels.TryGetValue(childLink.Node, out childIndex))
{
childIndex = labels.Count + 1;
labels.Add(childLink.Node, childIndex);
}
text.AppendLine($"node1 -> node{childIndex} [label=\" {childLink.Label}\"]");
}
foreach (var link in Visit(order))
{
int index = 0;
if (!labels.TryGetValue(link.Node, out index))
{
index = labels.Count + 1;
labels.Add(link.Node, index);
}
if (link.Node.IsFinal)
{
text.AppendLine($"node{index}[label=\"*\"]");
}
else
{
text.AppendLine($"node{index}[label=\"\"]");
}
foreach (var childLink in GetChildrenFromNode(link.Node, order))
{
int childIndex = 0;
if (!labels.TryGetValue(childLink.Node, out childIndex))
{
childIndex = labels.Count + 1;
labels.Add(childLink.Node, childIndex);
}
text.AppendLine($"node{index} -> node{childIndex} [label=\" {childLink.Label}\"]");
}
}
text.AppendLine("}");
return(text.ToString());
}
private IEnumerable <ChildLink> GetChildrenFromNode(INode node, TrieOrder order)
{
var result = node.Children;
if (order == TrieOrder.Asc)
{
result = result.OrderBy(c => c.Label, comparer);
}
else if (order == TrieOrder.Desc)
{
result = result.OrderByDescending(c => c.Label, comparer);
}
return(result);
}
private IEnumerable <ChildLink> Visit(TrieOrder order)
{
var stack = new Stack <ChildLink>();
foreach (var child in GetChildrenFromNode(root, order))
{
stack.Push(child);
}
while (stack.Count > 0)
{
var current = stack.Pop();
foreach (var child in GetChildrenFromNode(current.Node, order))
{
stack.Push(child);
}
yield return(current);
}
}
public IEnumerable <TrieMatch <T> > Match(ITrieMatcher <T> matcher, TrieOrder order)
{
var stack = new Stack <IEnumerator <ChildLink> >();
stack.Push(GetChildrenFromNode(root, order).GetEnumerator());
var result = new List <T>();
try
{
while (stack.Count > 0)
{
var current = stack.Peek();
if (!current.MoveNext())
{
if (result.Count > 0)
{
matcher.Pop();
result.RemoveAt(result.Count - 1);
}
current.Dispose();
stack.Pop();
continue;
}
var key = current.Current.Label;
var match = matcher.Next(key);
if (match)
{
result.Add(key);
//TODO: Improve performance by checking only intersection of next characters from matcher and children
var matchNode = current.Current.Node;
stack.Push(GetChildrenFromNode(matchNode, order).GetEnumerator());
if (matchNode.IsFinal && matcher.IsFinal())
{
yield return(new TrieMatch <T>(result));
}
}
}
}
finally
{
while (stack.Count > 0)
{
var current = stack.Peek();
if (result.Count > 0)
{
matcher.Pop();
result.RemoveAt(result.Count - 1);
}
current.Dispose();
stack.Pop();
}
}
}
