/*
* Copyright 2003-2016 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.textgen.trace;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.jetbrains.mps.openapi.model.SNodeReference;
import java.util.Iterator;
import java.util.List;
import java.util.function.Consumer;
/**
* Handles peculiarities of BL -> Java code textgen to find best match for node in a certain line.
* <p/>
* Here's comment as it used to be in TraceInfoUtil.getJavaNode:
* <p/>
* each node in base language owns a '\n' symbol in a previous line
* in the following code we will never get 'for' node querying line 1:
* <pre>
* 1. for (...) {
* 2. some statement
* 3. }
* </pre>
* since 'some statement' takes lines 1-2 instead of just line 2
*
* @author Artem Tikhomirov
* @since 3.4
*/
public final class BaseLanguageNodeLookup {
private final DebugInfo myDebugInfo;
public BaseLanguageNodeLookup(@NotNull DebugInfo debugInfo) {
myDebugInfo = debugInfo;
}
@Nullable
public SNodeReference getNodeAt(@NotNull String fileName, int line) {
final List<SNodeReference> nodes = myDebugInfo.getTracedNodesForPosition(fileName, line, new PositionFilter(line));
return nodes.isEmpty() ? null : nodes.get(0);
}
private static class PositionFilter implements Consumer<List<TraceablePositionInfo>> {
private final int myLineNumber;
public PositionFilter(int lineNumber) {
myLineNumber = lineNumber;
}
@Override
public void accept(List<TraceablePositionInfo> traceablePositionInfos) {
if (traceablePositionInfos.size() < 2) {
return; // why bother?
}
final Iterator<TraceablePositionInfo> it = traceablePositionInfos.iterator();
TraceablePositionInfo next;
// I assume list of positions sorted by starting line, with closest position coming first, and greatest line number == myLineNumber.
// We gonna strip all nodes that start at that line but do not occupy the whole line (provided there's another node in the same line)
while (it.hasNext() && (next = it.next()).getStartLine() == myLineNumber) {
if (next.getStartPosition() > 0 && it.hasNext()) {
// startPosition > 0 == not the whole line
// it.hasNext() - even if doesn't occupy line from the very beginning, leave the one unless there are better candidates
it.remove();
}
}
}
}
}