/*
* Copyright 2000-2015 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 com.intellij.codeInsight.editorActions.enter;
import com.intellij.codeInsight.CodeInsightSettings;
import com.intellij.codeInsight.highlighting.BraceMatcher;
import com.intellij.codeInsight.highlighting.BraceMatchingUtil;
import com.intellij.lang.ASTNode;
import com.intellij.lang.Language;
import com.intellij.openapi.actionSystem.DataContext;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.editor.Document;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.editor.actionSystem.EditorActionHandler;
import com.intellij.openapi.editor.ex.EditorEx;
import com.intellij.openapi.editor.highlighter.EditorHighlighter;
import com.intellij.openapi.editor.highlighter.HighlighterIterator;
import com.intellij.openapi.fileTypes.FileType;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.Pair;
import com.intellij.openapi.util.Ref;
import com.intellij.openapi.util.TextRange;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.psi.PsiDocumentManager;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import com.intellij.psi.TokenType;
import com.intellij.psi.codeStyle.CodeStyleManager;
import com.intellij.psi.tree.IElementType;
import com.intellij.psi.util.PsiUtilCore;
import com.intellij.util.IncorrectOperationException;
import com.intellij.util.text.CharArrayUtil;
import org.jetbrains.annotations.NotNull;
public class EnterAfterUnmatchedBraceHandler extends EnterHandlerDelegateAdapter {
private static final Logger LOG = Logger.getInstance("#com.intellij.codeInsight.editorActions.enter.EnterAfterUnmatchedBraceHandler");
@Override
public Result preprocessEnter(@NotNull final PsiFile file,
@NotNull final Editor editor,
@NotNull final Ref<Integer> caretOffsetRef,
@NotNull final Ref<Integer> caretAdvance,
@NotNull final DataContext dataContext,
final EditorActionHandler originalHandler) {
int caretOffset = caretOffsetRef.get();
if (!isApplicable(file, caretOffset)) {
return Result.Continue;
}
int maxRBraceCount = getMaxRBraceCount(file, editor, caretOffset);
if (maxRBraceCount > 0) {
insertRBraces(file, editor,
caretOffset,
getRBraceOffset(file, editor, caretOffset),
generateStringToInsert(editor, caretOffset, maxRBraceCount));
return Result.DefaultForceIndent;
}
return Result.Continue;
}
/**
* Checks that the text context is in responsibility of the handler.
*
* @param file target PSI file
* @param caretOffset target caret offset
* @return true, if handler is in charge
*/
public boolean isApplicable(@NotNull PsiFile file, int caretOffset) {
return true;
}
/**
* Calculates the maximum number of '}' that can be inserted by handler.
* Can return {@code 0} or less in custom implementation to skip '}' insertion in the {@code preprocessEnter} call
* and switch to default implementation.
*
* @param file target PSI file
* @param editor target editor
* @param caretOffset target caret offset
* @return maximum number of '}' that can be inserted by handler, {@code 0} or less to switch to default implementation
*/
protected int getMaxRBraceCount(@NotNull final PsiFile file, @NotNull final Editor editor, int caretOffset) {
if (!CodeInsightSettings.getInstance().INSERT_BRACE_ON_ENTER) {
return 0;
}
return Math.max(0, getUnmatchedLBracesNumberBefore(editor, caretOffset, file.getFileType()));
}
/**
* Calculates the string of '}' that have to be inserted by handler.
* Some languages can expand the string by additional characters (i.e. '\', ';')
*
* @param editor target editor
* @param caretOffset target caret offset
* @param maxRBraceCount the maximum number of '}' for insert at position, it always positive
* @return the string of '}' that has to be inserted by handler, it must have at least one '}'
*/
@NotNull
protected String generateStringToInsert(@NotNull final Editor editor, int caretOffset, int maxRBraceCount) {
assert maxRBraceCount > 0;
CharSequence text = editor.getDocument().getCharsSequence();
int bracesToInsert = 0;
for (int i = caretOffset - 1; i >= 0 && bracesToInsert < maxRBraceCount; --i) {
final char c = text.charAt(i);
if (c == '{') {
++bracesToInsert;
}
else if (isStopChar(c)) {
break;
}
}
return StringUtil.repeatSymbol('}', Math.max(bracesToInsert, 1));
}
/**
* Checks the character before the inserted '}' to reduce the count of inserted '}'.
* The number of inserted '}' will increase for each found '{'.
*
* @param c character to check
* @return true, to stop back iteration
*/
protected boolean isStopChar(char c) {
return " \n\t".indexOf(c) < 0;
}
/**
* Calculates the position for insertion of one or more '}'.
*
* @param file target PSI file
* @param editor target editor
* @param caretOffset target caret offset
* @return the position between {@code caretOffset} and the end of file
*/
protected int getRBraceOffset(@NotNull final PsiFile file, @NotNull final Editor editor, int caretOffset) {
CharSequence text = editor.getDocument().getCharsSequence();
int offset = CharArrayUtil.shiftForward(text, caretOffset, " \t");
final int fileLength = text.length();
if (offset < fileLength && ")];,%<?".indexOf(text.charAt(offset)) < 0) {
offset = calculateOffsetToInsertClosingBrace(file, text, offset).second;
//offset = CharArrayUtil.shiftForwardUntil(text, caretOffset, "\n");
}
return Math.min(offset, fileLength);
}
/**
* Inserts the {@code generatedRBraces} at the {@code rBracesInsertOffset} position and formats the code block.
* @param file target PSI file
* @param editor target editor
* @param caretOffset target caret offset
* @param rBracesInsertOffset target position to insert
* @param generatedRBraces string of '}' to insert
*/
protected void insertRBraces(@NotNull PsiFile file,
@NotNull Editor editor,
int caretOffset,
int rBracesInsertOffset,
String generatedRBraces) {
final Document document = editor.getDocument();
insertRBracesAtPosition(document, caretOffset, rBracesInsertOffset, generatedRBraces);
formatCodeFragmentBetweenBraces(file, document, caretOffset, rBracesInsertOffset, generatedRBraces);
}
/**
* Inserts the {@code rBracesCount} of '}' at the {@code rBracesInsertOffset} position.
*
* @param document target document
* @param caretOffset target caret offset
* @param rBracesInsertOffset target position to insert
* @param generatedRBraces string of '}' to insert
*/
protected void insertRBracesAtPosition(Document document, int caretOffset, int rBracesInsertOffset, String generatedRBraces) {
document.insertString(rBracesInsertOffset, "\n" + generatedRBraces);
// We need to adjust indents of the text that will be moved, hence, need to insert preliminary line feed.
// Example:
// if (test1()) {
// } else {<caret> if (test2()) {
// foo();
// }
// We insert here '\n}' after 'foo();' and have the following:
// if (test1()) {
// } else { if (test2()) {
// foo();
// }
// }
// That is formatted incorrectly because line feed between 'else' and 'if' is not inserted yet (whole 'if' block is indent anchor
// to 'if' code block('{}')). So, we insert temporary line feed between 'if' and 'else', correct indent and remove that temporary
// line feed.
document.insertString(caretOffset, "\n");
}
/**
* Formats the code block between caret and inserted braces.
*
* @param file target PSI file
* @param document target document
* @param caretOffset target caret offset
* @param rBracesInsertOffset target position to insert
* @param generatedRBraces string of '}' to insert
*/
protected void formatCodeFragmentBetweenBraces(@NotNull PsiFile file,
@NotNull Document document,
int caretOffset,
int rBracesInsertOffset,
String generatedRBraces) {
Project project = file.getProject();
long stamp = document.getModificationStamp();
boolean closingBraceIndentAdjusted;
try {
PsiDocumentManager.getInstance(project).commitDocument(document);
CodeStyleManager.getInstance(project).adjustLineIndent(file, new TextRange(caretOffset, rBracesInsertOffset + 2));
}
catch (IncorrectOperationException e) {
LOG.error(e);
}
finally {
closingBraceIndentAdjusted = stamp != document.getModificationStamp();
// do you remember that we insert the '\n'? here we take it back!
document.deleteString(caretOffset, caretOffset + 1);
}
// There is a possible case that formatter was unable to adjust line indent for the closing brace (that is the case for plain text
// document for example). Hence, we're trying to do the manually.
if (!closingBraceIndentAdjusted) {
int line = document.getLineNumber(rBracesInsertOffset);
StringBuilder buffer = new StringBuilder();
int start = document.getLineStartOffset(line);
int end = document.getLineEndOffset(line);
final CharSequence text = document.getCharsSequence();
for (int i = start; i < end; i++) {
char c = text.charAt(i);
if (c != ' ' && c != '\t') {
break;
}
else {
buffer.append(c);
}
}
if (buffer.length() > 0) {
document.insertString(rBracesInsertOffset + 1, buffer);
}
}
}
/**
* Current handler inserts closing curly brace (right brace) if necessary. There is a possible case that it should be located
* more than one line forward.
* <p/>
* <b>Example</b>
* <pre>
* if (test1()) {
* } else {<caret> if (test2()) {
* foo();
* }
* </pre>
* <p/>
* We want to get this after the processing:
* <pre>
* if (test1()) {
* } else {
* if (test2()) {
* foo();
* }
* }
* </pre>
* I.e. closing brace should be inserted two lines below current caret line. Hence, we need to calculate correct offset
* to use for brace inserting. This method is responsible for that.
* <p/>
* In essence it inspects PSI structure and finds PSE elements with the max length that starts at caret offset. End offset
* of that element is used as an insertion point.
*
* @param file target PSI file
* @param text text from the given file
* @param offset target offset where line feed will be inserted
* @return pair of (element, offset). The element is the '}' owner, if applicable; the offset is the position for inserting closing brace
*/
protected Pair<PsiElement, Integer> calculateOffsetToInsertClosingBrace(@NotNull PsiFile file, @NotNull CharSequence text, final int offset) {
PsiElement element = PsiUtilCore.getElementAtOffset(file, offset);
ASTNode node = element.getNode();
if (node != null && node.getElementType() == TokenType.WHITE_SPACE) {
return Pair.create(null, CharArrayUtil.shiftForwardUntil(text, offset, "\n"));
}
for (PsiElement parent = element.getParent(); parent != null; parent = parent.getParent()) {
ASTNode parentNode = parent.getNode();
if (parentNode == null || parentNode.getStartOffset() != offset) {
break;
}
element = parent;
}
if (element.getTextOffset() != offset) {
return Pair.create(null, CharArrayUtil.shiftForwardUntil(text, offset, "\n"));
}
return Pair.create(element, calculateOffsetToInsertClosingBraceInsideElement(element));
}
protected int calculateOffsetToInsertClosingBraceInsideElement(PsiElement element) {
return element.getTextRange().getEndOffset();
}
public static boolean isAfterUnmatchedLBrace(Editor editor, int offset, FileType fileType) {
return getUnmatchedLBracesNumberBefore(editor, offset, fileType) > 0;
}
/**
* Calculates number of unmatched left braces before the given offset.
*
* @param editor target editor
* @param offset target offset
* @param fileType target file type
* @return number of unmatched braces before the given offset;
* negative value if it's not possible to perform the calculation or if there are no unmatched left braces before
* the given offset
*/
protected static int getUnmatchedLBracesNumberBefore(Editor editor, int offset, FileType fileType) {
if (offset == 0) {
return -1;
}
CharSequence chars = editor.getDocument().getCharsSequence();
if (chars.charAt(offset - 1) != '{') {
return -1;
}
EditorHighlighter highlighter = ((EditorEx)editor).getHighlighter();
HighlighterIterator iterator = highlighter.createIterator(offset - 1);
BraceMatcher braceMatcher = BraceMatchingUtil.getBraceMatcher(fileType, iterator);
if (!braceMatcher.isLBraceToken(iterator, chars, fileType) || !braceMatcher.isStructuralBrace(iterator, chars, fileType)) {
return -1;
}
Language language = iterator.getTokenType().getLanguage();
iterator = highlighter.createIterator(0);
int lBracesBeforeOffset = 0;
int lBracesAfterOffset = 0;
int rBracesBeforeOffset = 0;
int rBracesAfterOffset = 0;
for (; !iterator.atEnd(); iterator.advance()) {
IElementType tokenType = iterator.getTokenType();
if (!tokenType.getLanguage().equals(language) || !braceMatcher.isStructuralBrace(iterator, chars, fileType)) {
continue;
}
boolean beforeOffset = iterator.getStart() < offset;
if (braceMatcher.isLBraceToken(iterator, chars, fileType)) {
if (beforeOffset) {
lBracesBeforeOffset++;
}
else {
lBracesAfterOffset++;
}
}
else if (braceMatcher.isRBraceToken(iterator, chars, fileType)) {
if (beforeOffset) {
rBracesBeforeOffset++;
}
else {
rBracesAfterOffset++;
}
}
}
return lBracesBeforeOffset - rBracesBeforeOffset - (rBracesAfterOffset - lBracesAfterOffset);
}
}