/// <summary>
/// a constructor.
/// </summary>
/// <param name="fieldTermStack"><see cref="FieldTermStack"/> object</param>
/// <param name="fieldQuery"><see cref="FieldQuery"/> object</param>
/// <param name="phraseLimit">maximum size of phraseList</param>
public FieldPhraseList(FieldTermStack fieldTermStack, FieldQuery fieldQuery, int phraseLimit)
{
string field = fieldTermStack.FieldName;
List <TermInfo> phraseCandidate = new List <TermInfo>();
QueryPhraseMap currMap = null;
QueryPhraseMap nextMap = null;
while (!fieldTermStack.IsEmpty && (phraseList.Count < phraseLimit))
{
phraseCandidate.Clear();
TermInfo ti = null;
TermInfo first = null;
first = ti = fieldTermStack.Pop();
currMap = fieldQuery.GetFieldTermMap(field, ti.Text);
while (currMap == null && ti.Next != first)
{
ti = ti.Next;
currMap = fieldQuery.GetFieldTermMap(field, ti.Text);
}
// if not found, discard top TermInfo from stack, then try next element
if (currMap == null)
{
continue;
}
// if found, search the longest phrase
phraseCandidate.Add(ti);
while (true)
{
first = ti = fieldTermStack.Pop();
nextMap = null;
if (ti != null)
{
nextMap = currMap.GetTermMap(ti.Text);
while (nextMap == null && ti.Next != first)
{
ti = ti.Next;
nextMap = currMap.GetTermMap(ti.Text);
}
}
if (ti == null || nextMap == null)
{
if (ti != null)
{
fieldTermStack.Push(ti);
}
if (currMap.IsValidTermOrPhrase(phraseCandidate))
{
AddIfNoOverlap(new WeightedPhraseInfo(phraseCandidate, currMap.Boost, currMap.TermOrPhraseNumber));
}
else
{
while (phraseCandidate.Count > 1)
{
//fieldTermStack.Push(phraseCandidate.Last.Value);
//phraseCandidate.RemoveLast();
TermInfo last = phraseCandidate[phraseCandidate.Count - 1];
phraseCandidate.Remove(last);
fieldTermStack.Push(last);
currMap = fieldQuery.SearchPhrase(field, phraseCandidate);
if (currMap != null)
{
AddIfNoOverlap(new WeightedPhraseInfo(phraseCandidate, currMap.Boost, currMap.TermOrPhraseNumber));
break;
}
}
}
break;
}
else
{
phraseCandidate.Add(ti);
currMap = nextMap;
}
}
}
}
