private void mergeIntermediateStates() {
Map<Adjacency, Set<FSANode>> adjToNodes = new HashMap<>();
Set<FSANode> newCurMergeLevel = new HashSet<>();
Map<FSANode, FSANode> formerNodeToMergedNode = new HashMap<>();
for (FSANode node : curMergeLevel) {
boolean needToBreak = false;
for (Set<FSANode> targets : node.getLabelToTargets().values()) {
if (targets.size() > 1) {
updateBasedOnMerges(targets, formerNodeToMergedNode);
FSANode newNode = mergeNodes(targets);
targets.stream().forEach(n -> formerNodeToMergedNode.put(n, newNode));
if (newNode.needsToMergeOutgoingEdges()) {
newCurMergeLevel.add(newNode);
}
needToBreak = true;
}
}
if (needToBreak) {
break;
}
for (FSAEdge edge : node.getOutgoingEdges()) {
Adjacency adj = new Adjacency(edge);
Set<FSANode> nodesWithSameLabelToSameTarget = adjToNodes.get(adj);
if (nodesWithSameLabelToSameTarget == null) {
nodesWithSameLabelToSameTarget = new HashSet<>();
adjToNodes.put(adj, nodesWithSameLabelToSameTarget);
}
nodesWithSameLabelToSameTarget.add(node);
}
}
for (FSANode node : curMergeLevel) {
newCurMergeLevel.addAll(
node.getIncomingEdges().stream().map(e -> e.getSource()).collect(Collectors.toSet()));
}
for (Set<FSANode> nodes : adjToNodes.values()) {
updateBasedOnMerges(nodes, formerNodeToMergedNode);
if (nodes.size() > 1) {
FSANode newNode = mergeNodes(nodes);
if (!Collections.disjoint(newCurMergeLevel, nodes)) {
newCurMergeLevel.removeAll(nodes);
newCurMergeLevel.add(newNode);
}
for (FSANode node : nodes) {
formerNodeToMergedNode.put(node, newNode);
}
}
}
// remove any nodes that are now contained by other nodes
curMergeLevel =
newCurMergeLevel.stream().filter(n -> this.nodes.contains(n)).collect(Collectors.toSet());
}
