/*
* Copyright 2011-2014 Gregory Shrago
*
* 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 org.intellij.grammar.intention;
import com.intellij.codeInsight.intention.IntentionAction;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.Pair;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import com.intellij.psi.util.PsiTreeUtil;
import com.intellij.util.IncorrectOperationException;
import org.intellij.grammar.psi.BnfChoice;
import org.intellij.grammar.psi.BnfExpression;
import org.intellij.grammar.psi.impl.BnfElementFactory;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
/**
* @author Vadim Romansky
* @author gregsh
*/
public class BnfFlipChoiceIntention implements IntentionAction {
@NotNull
@Override
public String getText() {
return "Flip arguments";
}
@NotNull
@Override
public String getFamilyName() {
return "Flip Choice Intention";
}
@Override
public boolean isAvailable(@NotNull Project project, Editor editor, PsiFile file) {
return getArguments(file, editor.getCaretModel().getOffset()) != null;
}
@Override
public void invoke(@NotNull Project project, Editor editor, PsiFile file) throws IncorrectOperationException {
final Pair<PsiElement, PsiElement> arguments = getArguments(file, editor.getCaretModel().getOffset());
if (arguments == null) return;
PsiElement newFirst = BnfElementFactory.createRuleFromText(project, "a ::=" + arguments.second.getText()).getExpression();
PsiElement newSecond = BnfElementFactory.createRuleFromText(project, "a ::=" + arguments.first.getText()).getExpression();
arguments.second.replace(newSecond);
arguments.first.replace(newFirst);
}
@Nullable
private Pair<PsiElement, PsiElement> getArguments(PsiFile file, int offset) {
PsiElement element = file.getViewProvider().findElementAt(offset);
final BnfChoice choice = PsiTreeUtil.getParentOfType(element, BnfChoice.class);
if (choice == null) return null;
for (PsiElement cur = choice.getFirstChild(), prev = null; cur != null; cur = cur.getNextSibling()) {
if (!(cur instanceof BnfExpression) ) continue;
int start = prev == null? choice.getTextRange().getStartOffset() : prev.getTextRange().getEndOffset();
int end = cur.getTextRange().getStartOffset();
if (start <= offset && offset <= end) return Pair.create(cur, prev);
prev = cur;
}
return null;
}
@Override
public boolean startInWriteAction() {
return true;
}
}