/*
* Copyright 2003-2011 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jetbrains.mps.newTypesystem.relations;
import jetbrains.mps.newTypesystem.SubTypingManagerNew;
import jetbrains.mps.newTypesystem.SubtypingUtil;
import jetbrains.mps.newTypesystem.state.State;
import jetbrains.mps.newTypesystem.state.blocks.RelationBlock;
import jetbrains.mps.newTypesystem.state.blocks.RelationKind;
import org.jetbrains.mps.openapi.model.SNode;
import jetbrains.mps.typesystem.inference.EquationInfo;
import jetbrains.mps.typesystem.inference.TypeChecker;
import jetbrains.mps.typesystemEngine.util.LatticeUtil;
import java.util.*;
public class ComparableRelation extends AbstractRelation {
@Override
public boolean accept(RelationKind kind) {
return kind.isComparable();
}
@Override
public boolean solve(SNode node, Set<SNode> leftTypes, Set<SNode> rightTypes, State state, Map<SNode, RelationBlock> typesToBlocks) {
EquationInfo info;
List<SNode> nodes = new LinkedList<SNode>();
nodes.addAll(leftTypes);
nodes.addAll(rightTypes);
if (nodes.isEmpty()) {
return false;
}
// TODO: why not use global TypeChecker? there can be the only one, after all
SubTypingManagerNew subTypingManager = (SubTypingManagerNew) TypeChecker.getInstance().getSubtypingManager();
nodes = SubtypingUtil.eliminateSuperTypes(nodes);
List<SNode> types = new LinkedList<SNode>();
SNode result = null;
for (SNode type : nodes) {
for (SNode toCompare : types) {
if (!subTypingManager.isComparable(type, toCompare, true)) {
result = type;
}
}
types.add(type);
}
if (result == null) {
result = createMeet(nodes);
}
if (result != null) {
RelationBlock block = typesToBlocks.get(result);
info = (block != null) ? block.getEquationInfo() : typesToBlocks.get(nodes.iterator().next()).getEquationInfo();
state.addEquation(node, result, info);
}
return result != null;
}
private SNode createMeet(List<SNode> nodes) {
if (nodes.size() > 1) {
nodes = SubtypingUtil.eliminateSuperTypes(nodes);
}
return LatticeUtil.meetNodes(new LinkedHashSet<SNode>(nodes));
}
}