@Override
public List<IBool> checkConsistency(IModel model) {
if (!lazy_scheduling) {
return Collections.emptyList();
} else {
List<IBool> constraints = new ArrayList<>();
IConstraintNetwork network = solver.getConstraintNetwork();
final Map<IObject, Collection<IFormula>> formulas = getFormulas(model);
IStaticCausalGraph causal_graph = solver.getStaticCausalGraph();
if (!closed_batteries
&& solver
.getCurrentNode()
.getFlaws()
.stream()
.map(
flaw -> {
if (flaw instanceof IGoal) {
return causal_graph.getNode(((IGoal) flaw).getFormula().getType());
} else if (flaw instanceof IFact) {
return causal_graph.getNode(((IFact) flaw).getFormula().getType());
} else if (flaw instanceof IDisjunctionFlaw) {
return causal_graph.getNode(((IDisjunctionFlaw) flaw).getDisjunction());
} else if (flaw instanceof IPreferenceFlaw) {
return causal_graph.getNode(((IPreferenceFlaw) flaw).getPreference());
} else {
throw new AssertionError(
"Flaw " + flaw.getClass().getName() + " is supported yet..");
}
})
.noneMatch(
node ->
causal_graph.existsPath(node, causal_graph.getNode(charge_predicate))
|| causal_graph.existsPath(
node, causal_graph.getNode(consume_predicate)))) {
// We need a resolver in order to re-open the resource when backtracking
solver
.getCurrentNode()
.addResolver(
new IResolver() {
private boolean resolved = false;
@Override
public double getKnownCost() {
return 0;
}
@Override
public void resolve() {
assert !resolved;
// Let's close the batteries
closed_batteries = true;
resolved = true;
}
@Override
public boolean isResolved() {
return resolved;
}
@Override
public void retract() {
assert resolved;
closed_batteries = false;
resolved = false;
}
});
}
if (closed_batteries) {
instances.forEach(
battery -> {
Collection<IFormula> c_formulas = formulas.get(battery);
BatteryTimeline timeline = new BatteryTimeline(solver, model, battery, c_formulas);
for (int i = 0; i < timeline.values.size(); i++) {
// <editor-fold defaultstate="collapsed" desc="battery overcharge">
if (model.evaluate(
network.gt(timeline.values.get(i).max_amount, timeline.capacity))) {
// We have a battery overcharge so we need to anticipate consumptions to charges
Collection<IFormula> good_charges = new ArrayList<>(c_formulas.size());
Collection<IFormula> good_consumptions = new ArrayList<>(c_formulas.size());
for (IFormula f : c_formulas) {
switch (f.getType().getName()) {
case CHARGE_PREDICATE_NAME:
if (model.evaluate(
network.leq(
(INumber) f.get(Constants.START),
network.newReal(timeline.pulses.get(i).toString())))) {
// Charges that affect current overcharge are all those that start before
// this timeline value
good_charges.add(f);
}
break;
case CONSUME_PREDICATE_NAME:
if (model.evaluate(
network.geq(
(INumber) f.get(Constants.END),
network.newReal(timeline.pulses.get(i + 1).toString())))) {
// Consumptions that might resolve the current overcharge are all those
// that end after this timeline value
good_consumptions.add(f);
}
break;
default:
throw new AssertionError(f.getType().getName());
}
}
List<IBool> or = new ArrayList<>(good_charges.size() * good_consumptions.size());
good_consumptions.forEach(
(cons) -> {
good_charges.forEach(
(charge) -> {
or.add(
network.leq(
cons.get(Constants.END), charge.get(Constants.START)));
or.add(network.not(cons.getScope().eq(charge.getScope())));
});
});
or.add(network.geq(battery.get(CAPACITY), timeline.values.get(i).max_amount));
constraints.add(network.or(or.toArray(new IBool[or.size()])));
}
// </editor-fold>
// <editor-fold defaultstate="collapsed" desc="battery overconsumption">
if (model.evaluate(
network.lt(timeline.values.get(i).min_amount, network.newReal("0")))) {
// We have a battery overconsumption so we need to anticipate charges to
// consumption
Collection<IFormula> good_charges = new ArrayList<>(c_formulas.size());
Collection<IFormula> good_consumptions = new ArrayList<>(c_formulas.size());
for (IFormula f : c_formulas) {
switch (f.getType().getName()) {
case CHARGE_PREDICATE_NAME:
if (model.evaluate(
network.geq(
(INumber) f.get(Constants.END),
network.newReal(timeline.pulses.get(i + 1).toString())))) {
// Charges that might resolve the current overconsumption are all those
// that end after this timeline value
good_charges.add(f);
}
break;
case CONSUME_PREDICATE_NAME:
if (model.evaluate(
network.leq(
(INumber) f.get(Constants.START),
network.newReal(timeline.pulses.get(i).toString())))) {
// Consumptions that affect current overconsumption are all those that
// start before this timeline value
good_consumptions.add(f);
}
break;
default:
throw new AssertionError(f.getType().getName());
}
}
List<IBool> or = new ArrayList<>(good_charges.size() * good_consumptions.size());
good_consumptions.forEach(
(cons) -> {
good_charges.forEach(
(charge) -> {
or.add(
network.leq(
charge.get(Constants.END), cons.get(Constants.START)));
or.add(network.not(charge.getScope().eq(cons.getScope())));
});
});
or.add(network.leq(network.newReal("0"), timeline.values.get(i).min_amount));
constraints.add(network.or(or.toArray(new IBool[or.size()])));
}
// </editor-fold>
}
if (timeline.values.isEmpty()
? model.evaluate(network.not(timeline.initial_amount.eq(timeline.final_amount)))
: model.evaluate(
network.not(
timeline
.values
.get(timeline.values.size() - 1)
.final_amount
.eq(timeline.final_amount)))) {
// The initial amount plus the sum of charges and consumptions is not equal to the
// final amount
final List<INumber> sum = new ArrayList<>(c_formulas.size() + 1);
sum.add(battery.get(INITIAL_AMOUNT));
sum.addAll(
c_formulas
.stream()
.map(
f -> {
switch (f.getType().getName()) {
case CHARGE_PREDICATE_NAME:
return f.get(C_AMOUNT);
case CONSUME_PREDICATE_NAME:
return network.negate((INumber) f.get(AMOUNT));
default:
throw new AssertionError(f.getType().getName());
}
})
.collect(Collectors.toList()));
final List<IBool> or = new ArrayList<>();
c_formulas.forEach(
formula -> {
or.add(network.not(battery.eq(formula.getScope())));
});
instances
.stream()
.filter(instance -> (instance != battery))
.forEach(
instance -> {
formulas
.get(instance)
.forEach(
formula -> {
or.add(battery.eq(formula.getScope()));
});
});
if (sum.size() == 1) {
or.add(network.eq(sum.get(0), (INumber) battery.get(FINAL_AMOUNT)));
} else {
or.add(
network.eq(
network.add(sum.toArray(new INumber[sum.size()])),
(INumber) battery.get(FINAL_AMOUNT)));
}
constraints.add(network.or(or.toArray(new IBool[or.size()])));
}
});
}
return constraints;
}
}
@Override
public void extractLandmarks() {
candidates.clear();
landmarks.clear();
rpgs.clear();
Set<IStaticCausalGraph.INode> nodes =
causal_graph.getNodes().stream().collect(Collectors.toSet());
// We define the initial state ..
Set<IStaticCausalGraph.IPredicateNode> init_state =
nodes
.stream()
.filter(node -> node instanceof IStaticCausalGraph.IPredicateNode)
.map(node -> (IStaticCausalGraph.IPredicateNode) node)
.flatMap(
predicate ->
predicate
.getPredicate()
.getInstances()
.stream()
.map(instance -> (IFormula) instance)
.filter(formula -> formula.getFormulaState() == FormulaState.Active))
.map(formula -> causal_graph.getNode(formula.getType()))
.collect(Collectors.toSet());
// .. and the goal state
Set<IStaticCausalGraph.IPredicateNode> goals =
nodes
.stream()
.filter(node -> node instanceof IStaticCausalGraph.IPredicateNode)
.map(node -> (IStaticCausalGraph.IPredicateNode) node)
.flatMap(
predicate ->
predicate
.getPredicate()
.getInstances()
.stream()
.map(instance -> (IFormula) instance)
.filter(formula -> formula.getFormulaState() == FormulaState.Inactive)
.map(formula -> causal_graph.getNode(formula.getType()))
.filter(node -> !init_state.contains(node)))
.collect(Collectors.toSet());
// We add high level goals to initial landmark candidates
goals
.stream()
.filter(node -> !init_state.contains(node))
.forEach(node -> candidates.add(new Landmark(node)));
// Main landmark extraction procedure loop
while (!candidates.isEmpty()) {
// The landmark candidate to analyze
ILandmark candidate = candidates.stream().findAny().get();
// We remove the landmark candidate from the candidates..
candidates.remove(candidate);
// .. and we add it to the landmarks
landmarks.put(candidate, new HashSet<>());
// These are the (disjunctive) causal preconditions of the first achievers..
Set<Set<IStaticCausalGraph.INode>> first_achievers_preconditions = new HashSet<>();
candidate
.getNodes()
.forEach(node -> first_achievers_preconditions.addAll(getPreconditions(node)));
// We compute the relaxed planning graph excluding the candidate ..
RelaxedPlanningGraph rpg = new RelaxedPlanningGraph(solver, candidate.getNodes());
rpg.extract();
rpg.propagate();
rpgs.put(candidate, rpg);
// .. and extract the causal preconditions of the first achievers according to the relaxed
// planning graph
// specifically, we remove those causal preconditions which are not reachable according to the
// relaxed planning graph without the candidate
first_achievers_preconditions.removeIf(
preconditions ->
preconditions.stream().anyMatch(pre -> Double.isInfinite(rpg.level(pre))));
// We compute the intersection of the preconditions (all of them must be true..)
Set<IStaticCausalGraph.INode> intersection =
new HashSet<>(first_achievers_preconditions.stream().findAny().get());
first_achievers_preconditions.forEach(
conjunction -> {
intersection.retainAll(conjunction);
});
intersection.removeIf(node -> init_state.contains(node));
if (!intersection.isEmpty()) {
// We remove from candidates those which are strictly worst than the current ones..
candidates.removeIf(
c ->
c.getNodes().size() > 1
&& intersection.stream().anyMatch(lm -> c.getNodes().contains(lm)));
// We remove from landmarks those which are strictly worst than the current ones..
landmarks
.entrySet()
.removeIf(
c ->
c.getKey().getNodes().size() > 1
&& intersection
.stream()
.anyMatch(lm -> c.getKey().getNodes().contains(lm)));
// We add new candidates to candidates (if they are not already in candidates nor in
// landmarks..)
intersection
.stream()
.filter(
node ->
candidates.stream().noneMatch(c -> c.getNodes().contains(node))
&& landmarks
.entrySet()
.stream()
.noneMatch(c -> c.getKey().getNodes().contains(node)))
.forEach(node -> candidates.add(new Landmark(node)));
}
// We compute a disjunctive landmark with oddments.. (at least one of them must be true..)
Set<IStaticCausalGraph.INode> symmetric_difference =
first_achievers_preconditions
.stream()
.flatMap(
conjunction -> conjunction.stream().filter(node -> !intersection.contains(node)))
.collect(Collectors.toSet());
if (!symmetric_difference.isEmpty()
&& symmetric_difference.stream().noneMatch(node -> init_state.contains(node))) {
// We remove from candidates those which are strictly worst than the current disjunctive
// landmark..
candidates.removeIf(
c ->
c.getNodes().containsAll(symmetric_difference)
&& c.getNodes().size() > symmetric_difference.size());
// We remove from landmarks those which are strictly worst than the current disjunctive
// landmark..
landmarks
.entrySet()
.removeIf(
c ->
c.getKey().getNodes().containsAll(symmetric_difference)
&& c.getKey().getNodes().size() > symmetric_difference.size());
// We consider the current disjunctive landmark only if there are not better candidates nor
// better landmarks..
if (candidates.stream().noneMatch(c -> symmetric_difference.containsAll(c.getNodes()))
&& landmarks
.entrySet()
.stream()
.noneMatch(c -> symmetric_difference.containsAll(c.getKey().getNodes()))) {
// We can add the disjunctive landmark to candidates
candidates.add(new Landmark(symmetric_difference));
}
}
}
// We compute natural orders between landmarks..
ILandmark[] lms = landmarks.keySet().stream().toArray(ILandmark[]::new);
for (int i = 0; i < lms.length; i++) {
if (lms[i].getNodes().size() == 1) {
// We extract orderings between unary landmarks..
RelaxedPlanningGraph c_rpg = rpgs.get(lms[i]);
for (int j = i + 1; j < lms.length; j++) {
if (lms[i].getNodes().size() == 1
&& lms[j]
.getNodes()
.stream()
.allMatch(node -> Double.isInfinite(c_rpg.level(node)))) {
// there is a natural order between landmarks lms[i] and lms[j]
landmarks.get(lms[i]).add(lms[j]);
}
}
}
}
}