/// <summary>
/// Lookup suggestions sorted by weight (descending order).
/// </summary>
/// <param name="collectAll">
/// If <c>true</c>, the routine terminates immediately when
/// <paramref name="num"/> suggestions have been collected. If
/// <c>false</c>, it will collect suggestions from all weight
/// arcs (needed for <see cref="LookupSortedAlphabetically"/>. </param>
private JCG.List <Completion> LookupSortedByWeight(BytesRef key, int num, bool collectAll)
{
// Don't overallocate the results buffers. This also serves the purpose of
// allowing the user of this class to request all matches using Integer.MAX_VALUE as
// the number of results.
JCG.List <Completion> res = new JCG.List <Completion>(Math.Min(10, num));
BytesRef output = BytesRef.DeepCopyOf(key);
for (int i = 0; i < rootArcs.Length; i++)
{
FST.Arc <object> rootArc = rootArcs[i];
FST.Arc <object> arc = (new FST.Arc <object>()).CopyFrom(rootArc);
// Descend into the automaton using the key as prefix.
if (DescendWithPrefix(arc, key))
{
// A subgraph starting from the current node has the completions
// of the key prefix. The arc we're at is the last key's byte,
// so we will collect it too.
output.Length = key.Length - 1;
if (Collect(res, num, rootArc.Label, output, arc) && !collectAll)
{
// We have enough suggestions to return immediately. Keep on looking
// for an
// exact match, if requested.
if (exactFirst)
{
if (!CheckExistingAndReorder(res, key))
{
int exactMatchBucket = GetExactMatchStartingFromRootArc(i, key);
if (exactMatchBucket != -1)
{
// Insert as the first result and truncate at num.
while (res.Count >= num)
{
res.RemoveAt(res.Count - 1);
}
res.Insert(0, new Completion(key, exactMatchBucket));
}
}
}
break;
}
}
}
return(res);
}