public TrieNodePtr(TrieNodePtr parent, TrieNode childNode)
: this(childNode)
{
leftChangeIndex = parent.leftChangeIndex;
rightChangeIndex = parent.rightChangeIndex;
numChanges = parent.numChanges;
}
public TrieNodePtr(TrieNodePtr parent, TrieNode childNode, int newIndex)
: this(childNode)
{
leftChangeIndex = parent.numChanges == 0 ? newIndex : parent.leftChangeIndex;
rightChangeIndex = newIndex;
numChanges = parent.numChanges + 1;
}
//Given text, find out what words match starting from startIdx
public void parseText(string text, out List<WordMatch> matches, int startIdx = 0)
{
matches = new List<WordMatch>(10);
List<TrieNodePtr> listPtrs = new List<TrieNodePtr>();
TrieNodePtr root = new TrieNodePtr(this);
listPtrs.Add(root);
//Start from the root node and walk down text, we maintain a list
//because we can change 1 character every TrieNode.minDistance
for (int cIdx = startIdx; cIdx < text.Length; ++cIdx)
{
char c = text[cIdx];
int cInt = (int)c - aInt;
TrieNodePtr.doMatch(cIdx - startIdx, cInt, ref listPtrs, matches);
if (listPtrs.Count == 0)
{
return;
}
}
}
public static void doMatch(int cIdx, int cInt, ref List<TrieNodePtr> list, List<WordMatch> matches)
{
List<TrieNodePtr> newList = new List<TrieNodePtr>();
Logger.LogTrace("doMatch cIdx: {} char: {} list size {} matches size {}",
cIdx, (char)(cInt + (int)'a'), list.Count, matches.Count);
foreach (TrieNodePtr nodePtr in list)
{
//Found a direct match
if (nodePtr.node.children[cInt] != null)
{
TrieNodePtr newNp = new TrieNodePtr(nodePtr, nodePtr.node.children[cInt]);
newList.Add(newNp);
newNp.addMatches(matches);
}
//If last change > 5, then add the rest of the children
if (nodePtr.numChanges == 0 || cIdx - nodePtr.rightChangeIndex >= minDistance)
{
foreach (var x in nodePtr.node.childrenList)
{
int charInt = x.Item1;
TrieNode childNode = x.Item2;
//Ignore direct match, was taken care of above
if (charInt == cInt)
continue;
TrieNodePtr newNp = new TrieNodePtr(nodePtr, childNode, cIdx);
newList.Add(newNp);
newNp.addMatches(matches);
}
}
}
list = newList;
}
