import java.util.Objects;
import java.util.Set;
import java.util.stream.Collectors;

/**
 * Represents a node in the dependency graph.
 */
public class NodeState implements DependencyGraphNode {
    private static final Logger LOGGER = LoggerFactory.getLogger(NodeState.class);
    private final Long nodeId;
    private final ComponentState component;
    private final List<EdgeState> incomingEdges = new ArrayList<>();

        public Candidate(NodeState node, Capability capability, Collection<NodeState> implicitCapabilityProviders) {
            this.node = node;
            this.capability = capability;
            this.implicitCapabilityProviders = implicitCapabilityProviders;
        }

        @Override
        public NodeState getNode() {
            return node;
        }

        @Override

    public Long getSelectedVariant() {
        NodeState node = getSelectedNode();
        if (node == null) {
            return null;
        } else {
            return node.getNodeId();
        }
    }

    @Nullable
    public NodeState getSelectedNode() {
        if (resolvedVariant != null) {
            return resolvedVariant;
        }
        List<NodeState> targetNodes = findTargetNodes();

                            List<NodeState> nodes = version.getNodes();
                            for (NodeState nodeState : nodes) {
                                // Collect nodes as implicit capability providers if different than current node, selected and not having explicit capabilities
                                if (node != nodeState && nodeState.isSelected() && doesNotDeclareExplicitCapability(nodeState)) {

        this.reportActivePending = true;
    }

    void registerConstraintProvider(NodeState nodeState) {
        if (hardEdges != 0) {
            throw new IllegalStateException("Cannot add a pending node for a dependency which is not pending");
        }
        constraintProvidingNodes.add(nodeState);
        if (nodeState.getComponent().getModule().isVirtualPlatform()) {
            reportActivePending = false;
        }

        for (NodeState node : nodes) {
            if (node.isSelected()) {
                consumer.accept(node);
            }
        }
    }

    @Override
    public List<ComponentState> getDependents() {
        List<ComponentState> incoming = Lists.newArrayListWithCapacity(nodes.size());
        for (NodeState node : nodes) {

    private collectOwnStrictVersions(NodeState node, List<String> children) {
        Set<ModuleIdentifier> constraintsSet = []
        for (String child : children) {
            node.maybeCollectStrictVersions(constraintsSet, edge(node, true, child, nextNode(), true).dependencyState)
        }
        node.storeOwnStrictVersions(constraintsSet)
    }

        private final VirtualPlatformState platformState;
        private final NodeState from;
        private final ComponentIdentifier platformId;

        public LenientPlatformConfigurationMetadata(VirtualPlatformState platform, ModuleComponentIdentifier componentId, NodeState from, @Nullable ComponentIdentifier platformId) {

        });
        selectorState.update(dependencyState);
        return selectorState;
    }

    @Nullable
    public NodeState peek() {
        return queue.isEmpty() ? null : queue.getFirst();
    }

    public NodeState pop() {
        NodeState next = queue.removeFirst();
        return next.dequeue();
    }

    /**

        return pendingDependencies;
    }

    void registerConstraintProvider(NodeState node) {
        pendingDependencies.registerConstraintProvider(node);
    }

    void unregisterConstraintProvider(NodeState nodeState) {
        pendingDependencies.unregisterConstraintProvider(nodeState);
    }

    public void maybeUpdateSelection(ResolutionConflictTracker conflictTracker) {