/// <summary>
/// Delete_alpha_memories the specified amem.
/// </summary>
/// <param name="amem">The amem.</param>
private void delete_alpha_memory(AlphaMemory amem)
{
Console.WriteLine(amem);
throw new Exception();
}
/// <summary>
/// The function for creating new negative nodes is similar to the ones for creating beta memories
/// and join nodes. However, one additional consideration is important with negative conditions,
/// and also with conjunctive negations. Any time there is a variable <v> which is tested in a negative
/// condition and bound in one or more other (positive) conditions, at least one of these positive
/// conditions must come before the negative condition. Recall that when we add a production to
/// the network, the network-construction routines are given a list of its conditions in some order. If
/// all conditions are positive, any order will work. Negative conditions require the aforementioned
/// constraint on the order, though, because negative nodes need to be able to access the appropriate
/// variable bindings in tokens, and the tokens "seen" by negative nodes indicate only variable
/// bindings from earlier conditions, i.e., conditions higher up in the network.
/// </summary>
/// <param name="parent">The parent.</param>
/// <param name="am">The am.</param>
/// <param name="tests">The tests.</param>
/// <returns></returns>
private ReteNode build_or_share_negative_node(ReteNode parent, AlphaMemory am, ICollection<TestAtJoinNode> tests)
{
foreach (ReteNode child in parent.Children)
{
if (child.Type == ReteNodeType.Negative)
{
NegativeNode negativenodeChild = (NegativeNode) child;
if (negativenodeChild.AlphaMemory == am)
{
if (negativenodeChild.Tests.Count == 0 && tests.Count == 0)
{
return child;
}
else
{
//Need to compare tests...
throw new ApplicationException("Unhandled...");
}
}
}
}
NegativeNode new_node = new NegativeNode();
new_node.Type = ReteNodeType.Negative; // "negative";
new_node.Parent = parent;
parent.Children.AddToFront(new_node);
foreach (TestAtJoinNode test in tests)
{
new_node.Tests.Add(test);
}
new_node.AlphaMemory = am;
am.Successors.AddToFront(new_node);
++am.ReferenceCount;
new_node.NearestAncestorWithSameAmem = find_nearest_ancestor_with_same_amem(parent, am);
update_new_node_with_matches_from_above(new_node);
// *** Right Unlinking ***
if (new_node.Items.Count == 0)
{
am.Successors.Remove(new_node);
new_node.IsRightUnlinked = true;
}
// *** End Right Unlinking ***
return new_node;
}
/// <summary>
/// The next helper function is similar, except it handles join nodes rather than beta memory
/// nodes. The two additional arguments specify the alpha memory to which the join node must
/// be attached and the variable binding consistency checks it must perform. Note that there is no
/// need to call update-new-node-with-matches-from-above in this case, because a join node does not
/// store any tokens, and a newly created join node has no children onto which join results should
/// be passed.
/// </summary>
/// <param name="parent">The parent.</param>
/// <param name="am">The am.</param>
/// <param name="tests">The tests.</param>
/// <returns></returns>
private ReteNode build_or_share_join_node(BetaMemory parent, AlphaMemory am, ICollection<TestAtJoinNode> tests)
{
foreach (ReteNode child in parent.AllChildren)
{
if (child.Type == ReteNodeType.Join)
{
JoinNode childJoinNode = (JoinNode) child;
if (childJoinNode.AlphaMemory == am)
{
if (childJoinNode.Tests.Count == 0 && tests.Count == 0)
{
return child;
}
else
{
if (childJoinNode.Tests.Count == tests.Count)
{
bool testsMatch = true;
foreach (TestAtJoinNode test in tests)
{
if (childJoinNode.Tests.Contains(test) == false)
{
testsMatch = false;
continue;
}
}
if (testsMatch)
{
return child;
}
//Need to compare tests...
throw new ApplicationException("Unhandled...");
}
}
}
}
}
JoinNode new_node = new JoinNode();
new_node.Type = ReteNodeType.Join; // "join";
new_node.Parent = parent;
parent.Children.AddToFront(new_node);
parent.AllChildren.AddToFront(new_node);
foreach (TestAtJoinNode test in tests)
{
new_node.Tests.Add(test);
}
new_node.AlphaMemory = am;
am.Successors.AddToFront(new_node);
++am.ReferenceCount;
new_node.NearestAncestorWithSameAmem = find_nearest_ancestor_with_same_amem(parent, am);
// *** Right Unlinking ***
if (parent.Items.Count == 0)
{
am.Successors.Remove(new_node);
new_node.IsRightUnlinked = true;
}
else if (am.Items.Count == 0)
{
if ((parent is DummyTopNode) == false)
{
parent.Children.Remove(new_node);
new_node.IsRightUnlinked = true;
}
}
// *** End Right Unlinking ***
return new_node;
}
/// <summary>
/// Finally, we have a helper function for creating a new alpha memory for a given condition,
/// or finding an existing one to share. The implementation of this function depends on what type
/// of alpha net implementation is used. If we use a traditional data
/// ow network, as described in
/// Section 2.2.1, then we simply start at the top of the alpha network and work our way down,
/// sharing or building new constant test nodes:
/// </summary>
/// <param name="c">The c.</param>
/// <returns></returns>
private AlphaMemory build_or_share_alpha_memory(Condition c)
{
AlphaMemory am;
int attributeHash = c.Attribute.GetHashCode();
int valueHash = c.Value.GetHashCode();
int idHash = c.Id.GetHashCode();
if (_alpha_network.ContainsKey(attributeHash))
{
Dictionary<int, Dictionary<int, AlphaMemory>> valueDict = _alpha_network[attributeHash];
if (valueDict.ContainsKey(valueHash))
{
Dictionary<int, AlphaMemory> idDict = valueDict[valueHash];
if (idDict.ContainsKey(idHash))
{
am = idDict[idHash];
am.Conditions.Add(c.ToString());
return am;
}
else //no idHash
{
am = new AlphaMemory();
am.ReferenceCount = 0;
am.Label = "A" + (++_next_alpha_node);
am.Conditions.Add(c.ToString());
idDict.Add(idHash, am);
}
}
else //no valueHash
{
am = new AlphaMemory();
am.ReferenceCount = 0;
am.Label = "A" + (++_next_alpha_node);
am.Conditions.Add(c.ToString());
Dictionary<int, AlphaMemory> idDict = new Dictionary<int, AlphaMemory>(THIRD_LEVEL_ALPHA_HASH_INITIAL_SIZE);
idDict.Add(idHash, am);
valueDict.Add(valueHash, idDict);
}
}
else //no attribHash
{
am = new AlphaMemory();
am.ReferenceCount = 0;
am.Label = "A" + (++_next_alpha_node);
am.Conditions.Add(c.ToString());
Dictionary<int, AlphaMemory> idDict = new Dictionary<int, AlphaMemory>(THIRD_LEVEL_ALPHA_HASH_INITIAL_SIZE);
idDict.Add(idHash, am);
Dictionary<int, Dictionary<int, AlphaMemory>> valueDict = new Dictionary<int, Dictionary<int, AlphaMemory>>(SECOND_LEVEL_ALPHA_HASH_INITIAL_SIZE);
valueDict.Add(valueHash, idDict);
_alpha_network.Add(attributeHash, valueDict);
}
foreach (WME w in _working_memory)
{
if (check_constant_tests(w, c))
{
alpha_memory_activation(am, w);
}
}
return am;
}
/// <summary>
/// Whenever a new WME is filtered through the alpha network and reaches an alpha memory, we
/// simply add it to the list of other WMEs in that memory, and inform each of the attached join
/// nodes:
/// </summary>
/// <param name="node">The node.</param>
/// <param name="w">The w.</param>
private void alpha_memory_activation(AlphaMemory node, WME w)
{
ItemInAlphaMemory new_item = new ItemInAlphaMemory();
new_item.WME = w;
new_item.AlphaMemory = node;
node.Items.Add(new_item);
w.AlphaMemoryItems.AddToFront(new_item);
// *** Neo Integration ***
if (w.Value.TermType == TermType.EntityObject)
{
IFactProvider eo = (IFactProvider) w.Value.Value;
if (eo.MyFactsHaveBeenAsserted == false)
{
foreach (WME wme in eo.GenerateFactsForRelatedObject(w.Attribute.Value.ToString(), w.Identifier.Value as IFactProvider))
{
AddWME(wme);
}
}
}
if (w.Value.TermType == TermType.ObjectRelation)
{
ObjectRelationBase orb = (ObjectRelationBase) w.Value.Value;
foreach (RulesEnabledEntityObject eo in orb)
{
if (eo.MyFactsHaveBeenAsserted == false)
{
foreach (WME wme in eo.GenerateFactsForObjectInCollection(w.Attribute.Value.ToString(), orb))
{
AddWME(wme);
}
}
}
}
// *** End Neo Integration ***
//The unlinking process changes the underlying collection so we need a new collection...
BigList<ReteNode> successors = node.Successors.Clone();
foreach (ReteNode successor in successors)
{
right_activation(successor, w);
}
}
/// <summary>
/// For right unlinking, we need to initialize the nearest-ancestor-with-same-amem fields on
/// newly-created join and negative nodes. The find-nearest-ancestor-with-same-amem procedure
/// finds the appropriate value. It starts at a given node and walks up the beta network, returning
/// the first node it finds that uses a given alpha memory. Note that this node may be in the
/// subnetwork for a conjunctive negation.
/// </summary>
/// <param name="node">The node.</param>
/// <param name="am">The am.</param>
/// <returns></returns>
private ReteNode find_nearest_ancestor_with_same_amem(ReteNode node, AlphaMemory am)
{
if (node is DummyTopNode)
{
return null;
}
if (node.Type == ReteNodeType.Dummy)
{
return null;
}
if (node.Type == ReteNodeType.Join)
{
if (((JoinNode) node).AlphaMemory == am)
{
return node;
}
}
if (node.Type == ReteNodeType.Negative)
{
if (((NegativeNode) node).AlphaMemory == am)
{
return node;
}
}
if (node.Type == ReteNodeType.NCC)
{
return find_nearest_ancestor_with_same_amem(((NCCNode) node).Partner.Parent, am);
}
return find_nearest_ancestor_with_same_amem(node.Parent, am);
}
