pstlab / PLATINUm

public final class TimelineSchedulingResolver extends Resolver<StateVariable>

{

	private boolean load;

	private double schedulingCost;

	/**

	 * 

	 */

	protected TimelineSchedulingResolver() {

		super(ResolverType.TIMELINE_SCHEDULING_RESOLVER.getLabel(), 

				ResolverType.TIMELINE_SCHEDULING_RESOLVER.getFlawTypes());

		// set load flag

		this.load = false;

	}

	/**

	 * 

	 */

	private void load() {

		// get deliberative property file

		FilePropertyReader properties = new FilePropertyReader(

				FRAMEWORK_HOME + FilePropertyReader.DEFAULT_DELIBERATIVE_PROPERTY);

		// get weight

		this.schedulingCost = Double.parseDouble(properties.getProperty("scheduling-cost"));

		// set flag

		this.load = true;

	}

	/**

	 * 

	 */

	@Override

	protected void doApply(FlawSolution solution) 

			throws FlawSolutionApplicationException {

		// get the flaw solution to consider

		OverlappingSetSchedule schedule = (OverlappingSetSchedule) solution;

		// list of committed relations

		List<BeforeRelation> committed = new ArrayList<>();

		try {

			// apply all precedence constraints

			for (PrecedenceConstraint pc : schedule.getConstraints()) {

				// get reference and target decisions

				Decision reference = pc.getReference();

				Decision target = pc.getTarget();

				// create relation

				BeforeRelation before = this.component.create(

						RelationType.BEFORE, 

						reference, 

						target);

				// set bounds

				before.setBound(new long[] {

						0, 

						this.component.getHorizon()});

				// add created relation to solution

				solution.addCreatedRelation(before);

				// add relation to committed

				committed.add(before);

				// propagate relations

				this.component.activate(before);

				// add activated relations to solution

				solution.addActivatedRelation(before);

				// check feasibility

				this.tdb.verify();

			}

		} catch (RelationPropagationException | ConsistencyCheckException ex) {

			// write error message

			error("Error while applying flaw solution:\n"

					+ "- solution: " + solution + "\n");

			// clear data structure by remove all committed relations

			for (BeforeRelation before : committed) {

				// deactivate relation

				this.component.deactivate(before);

				// delete relation

				this.component.delete(before);

			}

			// not feasible solution

			throw new FlawSolutionApplicationException(ex.getMessage());

		}

	}

//	protected void doApply(FlawSolution solution) 

//			throws FlawSolutionApplicationException 

//	{

//		// get the flaw solution to consider

//		DecisionPrecedenceConstraint pc = (DecisionPrecedenceConstraint) solution;

//		// get reference and target decisions

//		Decision reference = pc.getReference();

//		Decision target = pc.getTarget();

//		

//		// create relation

//		BeforeRelation before = this.component.create(RelationType.BEFORE, reference, target);

//		// set bounds

//		before.setBound(new long[] {

//				0, 

//				this.component.getHorizon()});

//		// add created relation to solution

//		solution.addCreatedRelation(before);

//		

//		try

//		{

//			// propagate relations

//			this.component.activate(before);

//			// add activated relations to solution

//			solution.addActivatedRelation(before);

//			debug("Precedence constraint successfully created and activated:\n"

//					+ "- temporal constraint: " + before + "\n");

//			

//			// check feasibility

//			this.tdb.verify();

//		}

//		catch (RelationPropagationException | ConsistencyCheckException ex) 

//		{

//			// write error message

//			error("Error while applying flaw solution:\n"

//					+ "- solution: " + solution + "\n"

//					+ "- unfeasible precedence constraint: " + before + "\n");

//

//			// deactivate relation

//			this.component.deactivate(before);

//			// delete relation

//			this.component.delete(before);

//			// not feasible solution

//			throw new FlawSolutionApplicationException(ex.getMessage());

//		}

//	}

	/**

	 * 

	 */

	@Override

	protected List<Flaw> doFindFlaws() {

		// check flag

		if (!this.load) {

			this.load();

		}

		// list of critical sets

		List<Flaw> CSs = new ArrayList<>();

		// list of active decisions

		List<Decision> decisions = this.component.getActiveDecisions();

		// sort decisions

		Collections.sort(decisions);

		// look for critical sets

		for (int index = 0; index < decisions.size() - 1; index++) {

			// get active decision  

			Decision activity = decisions.get(index);

			// prepare a critical set

			OverlappingSet cs = new OverlappingSet(

					FLAW_COUNTER.getAndIncrement(), 

					this.component);

			// add current activity

			cs.add(activity);

			// find possibly overlapping decisions

			for (int jndex = index + 1; jndex < decisions.size(); jndex++) {

				// get another activity of the component

				Decision other = decisions.get(jndex);

				// check overlapping condition with the critical set

				if (this.conflict(cs, other)) {

					// add the activity to the critical set

					cs.add(other);

				}

			}

			// check the size of the critical set

			if (cs.size() > 1) {

				// the critical set actually represents a flaw of the component

				CSs.add(cs);

			}

		}

		// get the list of critical sets found

		return CSs;

	}

	/**

	 * Check if an activity overlaps ALL the activities composing a Critical Set

	 * 

	 * @param cs

	 * @param activity

	 * @return

	 */

	private boolean conflict(OverlappingSet cs, Decision activity) {

		// conflicting flag

		boolean conflict = true;

		// get events of the critical set

		List<Decision> activities = cs.getDecisions();

		// check set of events

		for (int index = 0; index < activities.size() && conflict; index++) {

			// get an activity of the critical set

			Decision csActivity = activities.get(index);

			// check overlapping condition

			IntervalOverlapQuery query = this.tdb.createTemporalQuery(TemporalQueryType.INTERVAL_OVERLAP);

			// set intervals

			query.setReference(csActivity.getToken().getInterval());

			query.setTarget(activity.getToken().getInterval());

			// process query

			this.tdb.process(query);

			// check whether the (flexible) temporal interval can overlap or not

			conflict = query.canOverlap();

		}

		// get result

		return conflict;

	}

//	@Override

//	protected List<Flaw> doFindFlaws() {

//		

//		// check flag

//		if (!this.load) {

//			this.load();

//		}

//		

//		// list of critical sets

//		List<Flaw> flaws = new ArrayList<>();

//		// list of active decisions

//		List<Decision> decisions = this.component.getActiveDecisions();

//		// sort decisions

//		Collections.sort(decisions);

//		

//		

//		// look for peaks

//		for (int index = 0; index < decisions.size() - 1; index++) {

//			// get active decision  

//			Decision reference = decisions.get(index);

//			// find possibly overlapping decisions

//			for (int jndex = index + 1; jndex < decisions.size(); jndex++)

//			{

//				// get another active decision

//				Decision target = decisions.get(jndex);

//				// check if intervals can overlap

//				IntervalOverlapQuery query = this.tdb.createTemporalQuery(

//						TemporalQueryType.INTERVAL_OVERLAP);

//				

//				// set time points

//				query.setReference(reference.getToken().getInterval());

//				query.setTarget(target.getToken().getInterval());

//				// process query

//				this.tdb.process(query);

//				// check overlapping 

//				if (query.canOverlap())

//				{

//					// conflict found

//					BinaryDecisionConflict c = new BinaryDecisionConflict(

//							FLAW_COUNTER.getAndIncrement(), 

//							this.component);

//

//					// set overlapping decisions

//					c.setDecisions(new Decision[] {

//							reference,

//							target

//					});

//					

//					// check if decisions overlaps

//					debug("Overlapping tokens:\n"

//							+ "- component: " + this.component + "\n"

//							+ "- reference token: " + reference + "\n"

//							+ "- target token: " + target + "\n");

//					

//					// add conflict

//					flaws.add(c);

//					

//					

//				} else {

//					

//					// check if decisions overlaps

//					debug("NOT overlapping tokens:\n"

//							+ "- component: " + this.component + "\n"

//							+ "- reference token: " + reference + "\n"

//							+ "- target token: " + target + "\n");

//				}

//			}

//		}

//		

//		// get the list

//		return flaws;

//	}

	/**

	 * 

	 */

	@Override

	protected void doComputeFlawSolutions(Flaw flaw) 

			throws UnsolvableFlawException {

		// get the critical set

		OverlappingSet cs = (OverlappingSet) flaw;

		/*

		 * A state variable does not allow any pair of overlapping of its activities. 

		 * 

		 * Each total ordering of the activities that compose a critical set may represent a solution

		 * 

		 */

		// compute all possible solutions of the critical set

		this.computeCriticalSetSolutions(cs);

	}

	/**

	 * 

	 * @param cs

	 * @throws UnsolvableFlawException

	 */

	private void computeCriticalSetSolutions(OverlappingSet cs) 

			throws UnsolvableFlawException {

		// get the list of overlapping activities

		List<Decision> activities = new ArrayList<>(cs.getDecisions());

		// compute feasible schedules

		this.doFindFeasibleSchedule(new ArrayList<>(), activities, cs);

		// check if no feasible solution exists

		if (cs.getSolutions().isEmpty()) {

			// unsolvable flaw

			throw new UnsolvableFlawException("Unsolvable flaw found on componnet \"" + this.component + "\"\n"

					+ "- flaw: " + cs + "\n\n");

		}

	}

	/**

	 * A solution to a critical set on a State Variable is a total ordering of the activities of the critical set.

	 * 

	 *  This method computes all possible orderings of the activities that are part of a critical set (i.e., the

	 *  permutations). The permutations that represent valid temporal constraints are considered as valid 

	 *  solutions to the critical set

	 * 

	 * @param schedule

	 * @param cs

	 * @param flaw

	 */

	private void doFindFeasibleSchedule(List<Decision> schedule, List<Decision> cs, OverlappingSet flaw) {

		// check if a schedule is ready for temporal checking

		if (cs.isEmpty()) {

			// check schedule resource feasibility first and then temporal feasibility

			if (this.checkTemporalFeasibility(schedule)) {

				// create flaw solution

				OverlappingSetSchedule solution = new OverlappingSetSchedule(flaw, this.schedulingCost);

				// set resulting constraints

				for (int i= 0; i < schedule.size() - 1; i++) {

					// add precedence constraint

					solution.addConstraint(schedule.get(i), schedule.get(i + 1));

				}

				// add solution to the flaw

				flaw.addSolution(solution);

			}

		} else {

			// check possible schedules until no solution is found 

			for (int index = 0; index < cs.size(); index++) {

				// get an activity from the critical set

				Decision activity = cs.remove(index);

				// add the activity to the possible schedule

				schedule.add(activity);

				// recursively build the permutation

				this.doFindFeasibleSchedule(schedule, cs, flaw);

				// remove event from the permutation

				schedule.remove(activity);

				// restore data of the critical set

				cs.add(index, activity);

			}

		}

	}

	/**

	 * 

	 * @param schedule

	 * @return

	 */

		// feasibility flag

		boolean feasible = true;

		// list of propagated constraints

		List<BeforeIntervalConstraint> committed = new ArrayList<>();

		// check pairs of events 

		for (int index = 0; index < schedule.size() - 1 && feasible; index++) {

			try {

				// get activities

				Decision a1 = schedule.get(index);

				Decision a2 = schedule.get(index + 1);

				// get associated tokens and temporal intervals to check schedule feasibility

				TemporalInterval i1 = a1.getToken().getInterval();

				TemporalInterval i2 = a2.getToken().getInterval();

				// create precedence constraint "i1 < i2"

				BeforeIntervalConstraint before = this.tdb.createTemporalConstraint(

						TemporalConstraintType.BEFORE);

				// set constraint data

				before.setReference(i1);

				before.setTarget(i2);

				before.setLowerBound(0);

				before.setUpperBound(this.tdb.getHorizon());

				// add constraints to committed

				committed.add(before);

				// propagate constraint

				this.tdb.propagate(before);

				// check temporal feasibility

				this.tdb.verify();

			} catch (TemporalConstraintPropagationException | ConsistencyCheckException ex) {

				// not feasible schedule

				feasible = false;

				// log data

				debug("Component [" + this.label + "] temporally unfeasible schedule:\n"

						+ "- potential schedule critical set: " + schedule + "\n");

			} finally  {

				// retract all committed constraints

				for (BeforeIntervalConstraint before : committed) {

					// retract temporal constraint

					this.tdb.retract(before);

				}

			}

		}

		// get feasibility flag

		return feasible;