internal InferenceLevel(InferenceLevel parent, WildcardTriplet condition, IEnumerable<InferenceStep> steps, Context context)
{
Condition = condition;
Depth = parent == null ? 0 : parent.Depth + 1;
_context = context;
_steps = steps.ToArray();
}
internal ImplicationStep(WildcardTriplet implicationCondition, TripletTree implicationResult, WildcardTriplet target, Context context)
: base(target, context)
{
_conditionReader = CreateRequirement(implicationCondition);
_implicationResult = implicationResult;
_conditionReader.AttachHandler(_handler_Condition);
}
internal AndStep(WildcardTriplet condition1, WildcardTriplet condition2, WildcardTriplet target, Context context)
: base(target, context)
{
_reader1 = CreateRequirement(condition1);
_reader2 = CreateRequirement(condition2);
_reader1.AttachHandler(reader1_Handler);
_reader2.AttachHandler(reader2_Handler);
}
internal static IEnumerable<InferenceStep> Provider(WildcardTriplet target, Context context)
{
if (!Predicate.And.Equals(target.SearchedPredicate))
yield break;
var condition1Tree = target.SearchedSubject as TripletTree;
var condition2Tree = target.SearchedObject as TripletTree;
if (condition1Tree == null || condition2Tree == null)
yield break;
yield return new AndStep(WildcardTriplet.Exact(condition1Tree), WildcardTriplet.Exact(condition2Tree), target, context);
}
internal static IEnumerable<InferenceStep> Provider(WildcardTriplet target, Context context)
{
foreach (var substitutedTree in context.FindSubstitutedSubtreeParents(target))
{
//find matching trees
var thenTrees = new List<TripletTree>();
substitutedTree.Each(t =>
{
if (Predicate.Then.Equals(t.Predicate))
thenTrees.Add(t);
});
//create steps according to database
foreach (var thenTree in thenTrees)
{
var condition = thenTree.Subject as TripletTree;
var implicationResult = thenTree.Object as TripletTree;
if (condition != null && implicationResult != null && target.IsSatisfiedBy(thenTree.Object as TripletTree))
{
yield return new ImplicationStep(WildcardTriplet.Exact(condition), implicationResult, target, context);
}
}
}
}
internal InferenceStep(WildcardTriplet target, Context context)
{
Target = target;
_context = context;
}
/// <summary>
/// Gets preconditions to given wildcard.
/// </summary>
/// <param name="wildcard">Wildcard which preconditions are requested.</param>
/// <returns></returns>
public IEnumerable<Precondition> Preconditions(WildcardTriplet wildcard)
{
var inference = new Context(this, wildcard);
return inference.Preconditions();
}
/// <summary>
/// Finds triplets according to given wildcard.
/// Including the inference.
/// </summary>
/// <param name="wildcard">The wildcard for search.</param>
/// <returns>Found triplets.</returns>
public IEnumerable<TripletTree> Find(WildcardTriplet wildcard)
{
var inference = new Context(this, wildcard);
return inference.Find();
}
internal OrStep(Context context)
: base(null, context)
{
}
internal static IEnumerable<InferenceStep> Provider(WildcardTriplet wildcard, Context context)
{
yield return new LookupStep(wildcard, context);
}
private LookupStep(WildcardTriplet target, Context context) :
base(target, context)
{
_context = context;
_triplets = lazyFindTriplets().GetEnumerator();
}