/// <summary>
/// Allows custom plans to be passed in.
/// </summary>
/// <param name="domain">The node's domain.</param>
/// <param name="problem">The node's problem.</param>
/// <param name="incoming">The node's incoming edge.</param>
/// <returns>A new tree node.</returns>
private MediationTreeNode CreateNode(Domain domain, Problem problem, MediationTreeEdge incoming, Plan plan)
{
// Create a placeholder for the new node object.
MediationTreeNode node = null;
// If the node is a root, initialize a root node.
if (incoming == null)
{
if (!data.superpositionManipulation)
{
node = new MediationTreeNode(domain, problem, 0);
}
else
{
node = new VirtualMediationTreeNode(domain, problem, 0);
}
}
// Otherwise, it is a child node...
else
{
// Store the current node's ID in the incoming edge.
incoming.Child = ++data.nodeCounter;
if (!data.superpositionManipulation)
{
node = new MediationTreeNode(domain, problem, incoming, GetSuccessorState(incoming), plan, incoming.Child, GetDepth(incoming.Parent) + 1);
}
else
{
node = new VirtualMediationTreeNode(domain, problem, incoming, GetSuccessorSuperposition(incoming), plan, incoming.Child, GetDepth(incoming.Parent) + 1);
}
// Add the edge to the tree hashtable.
data.tree[incoming.Child] = incoming.Parent;
MediationTreeNode parent = GetNode(incoming.Parent);
if (incoming.Action != null)
{
parent.Outgoing.Find(x => x.Action.Equals(incoming.Action)).Child = node.ID;
}
else
{
foreach (MediationTreeEdge edge in parent.Outgoing)
{
if (edge is VirtualMediationTreeEdge)
{
if ((edge as VirtualMediationTreeEdge).Equals(incoming as VirtualMediationTreeEdge))
{
edge.Child = node.ID;
}
}
}
}
SetNode(parent);
if (data.superpositionManipulation)
{
Superposition super = node.State as Superposition;
super.States = SuperpositionManipulator.Collapse(data.player, node as VirtualMediationTreeNode, SuperpositionChooser.ChooseUtility);
node.State = super;
}
}
// If the node is a goal state, iterate the goal state counter.
if (node.IsGoal)
{
data.goalStateCount++;
}
// If the node is a dead end, iterate the dead end counter.
if (node.DeadEnd)
{
if (data.eventRevision)
{
EventRevisor.EventRevision(Planner.FastDownward, node, this);
}
if (node.DeadEnd && data.domainRevision)
{
DomainRevisor.DomainRevision(Planner.FastDownward, node, this);
}
if (node.DeadEnd)
{
data.deadEndCount++;
}
}
// If the node is at a lower depth than the previous record holder, update the depth counter.
if (node.Depth > data.lowestDepth)
{
data.lowestDepth = node.Depth;
}
// If the node is not a dead end.
if (!node.DeadEnd)
{
// Find and store the node's outgoing edges.
node.Outgoing = GetOutgoingEdges(node, GetCurrentTurn(node));
}
// Save the current node to disk.
SetNode(node);
// Return the current node object.
return(node);
}
public static void DomainRevision(Planner planner, MediationTreeNode node, MediationTree tree)
{
// Store the incoming action.
Operator incoming = node.Incoming.Action as Operator;
// Create a new plan object.
Plan newPlan = new Plan();
List <Tuple <Operator, State> > knowledge = EventRevisor.GetWorldKnowledge(tree.Player, node, tree);
knowledge.RemoveAt(knowledge.Count - 1);
List <Operator> observedActions = new List <Operator>();
foreach (Tuple <Operator, State> pair in knowledge)
{
if (pair.First != null)
{
if (pair.First.Name.Equals(incoming.Name))
{
observedActions.Add(pair.First);
}
}
}
// Examine each exceptional effect.
foreach (Predicate effect in incoming.ExceptionalEffects)
{
// Create a new domain object.
Domain newDomain = node.Domain.Clone() as Domain;
newDomain.Operators = new List <IOperator>();
// If the current effect is conditional...
if (incoming.IsConditional(effect))
{
bool observed = false;
// If the conditional effect has not been observed by the player.
foreach (Operator action in observedActions)
{
if (!observed)
{
foreach (IAxiom conditional in action.Conditionals)
{
if (conditional.Effects.Contains(effect) && !observed)
{
observed = true;
}
}
}
}
// Remove the conditional effect from the domain.
if (!observed)
{
// Copy the current operator templates into a list.
List <IOperator> templates = new List <IOperator>();
foreach (IOperator templ in node.Domain.Operators)
{
templates.Add(templ.Clone() as IOperator);
}
// Create a clone of the incoming action's unbound operator template.
IOperator temp = incoming.Template() as Operator;
// Find the incoming action template in the domain list.
Operator template = templates.Find(t => t.Equals(temp)) as Operator;
// Remove the incoming action template from the domain list.
templates.Remove(template);
// Create a clone of the incoming action.
Operator clone = incoming.Clone() as Operator;
// Create a list of conditional effects to remove from the template.
List <IAxiom> remove = new List <IAxiom>();
foreach (IAxiom conditional in clone.Conditionals)
{
if (conditional.Effects.Contains(effect))
{
remove.Add(conditional);
}
}
// Remove each conditional effect from the template.
foreach (IAxiom rem in remove)
{
template.Conditionals.Remove(rem.Template() as IAxiom);
}
// Add the modified template to the domain list.
templates.Add(template);
// Push the modified list to the new domain object.
newDomain.Operators = templates;
// Clone the modified incoming action template.
Operator newAction = template.Clone() as Operator;
// Bind the cloned action with the incoming action's bindings.
newAction.Bindings = incoming.Bindings;
MediationTreeEdge newEdge = new MediationTreeEdge(newAction, ActionType.Exceptional, node.Incoming.Parent, node.ID);
Problem newProblem = node.Problem.Clone() as Problem;
newProblem.Initial = tree.GetSuccessorState(newEdge).Predicates;
// Find a new plan.
newPlan = PlannerInterface.Plan(planner, newDomain, newProblem);
// If the modified domain can accommodate the player's action...
if (newPlan.Steps.Count > 0)
{
node.Plan = newPlan;
node.Incoming.Action = newAction;
node.State = tree.GetSuccessorState(node.Incoming);
node.Domain = newDomain;
}
}
}
}
}