/// <summary>
/// Adds answer to the query node.
/// </summary>
/// <param name="answer">Answer to be added.</param>
/// <returns><c>true</c> if answer was added (it was new), <c>false</c> otherwise.</returns>
internal bool AddAnswer(NpletTree answer)
{
if (!_availableAnswerIndex.Add(answer))
return false;
_availableAnswers.Add(answer);
return true;
}
/// <summary>
/// Finds nplets satisfiing the query.
/// </summary>
/// <param name="query">The asked query.</param>
/// <returns>The satisfiing nplets.</returns>
internal IEnumerable<NpletTree> Find(NpletTree query)
{
var rootQueryNode = CreateQueryNode(query);
var rootReader = CreateReader(rootQueryNode);
var queriesToExpand = new Queue<NpletQueryNode>();
queriesToExpand.Enqueue(rootQueryNode);
_activeProducers.Clear();
while (queriesToExpand.Count > 0 || _activeProducers.Count > 0)
{
//firstly we will expand newest dependencies
expandQueries(queriesToExpand);
//secondly we produce new answers
produceAnswers();
while (rootReader.HasNewAnswer)
{
yield return rootReader.GetNextAnswer();
}
}
}
internal NpletQueryNode(NpletTree query)
{
Query = query;
}
/// <summary>
/// Finds triplets according to given wildcard.
/// Including the inference.
/// </summary>
/// <param name="nplet">The wildcard for search.</param>
/// <returns>Found nplets.</returns>
public IEnumerable<NpletTree> Find(NpletTree nplet)
{
throw new NotImplementedException();
}
/// <summary>
/// Fetches known nplets in form matching the query.
/// </summary>
/// <param name="query">Query used for matching of the nplets.</param>
/// <returns>The nplets</returns>
internal IEnumerable<NpletTree> Fetch(NpletTree query)
{
throw new NotImplementedException();
}
/// <summary>
/// Creates query node for given nplet.
/// </summary>
/// <param name="nplet">The nplet.</param>
/// <returns>The query node.</returns>
internal NpletQueryNode CreateQueryNode(NpletTree nplet)
{
return new NpletQueryNode(nplet);
}