public void insertNewline(boolean fixIndentation) {
textArea.getTextBuffer().getUndoBuffer().startCompoundEdit();
try {
final int startPosition = textArea.getSelectionStart();
CharSequence chars = textArea.getTextBuffer();
int startLineIndex = textArea.getLineOfOffset(startPosition);
int startLineStartOffset = textArea.getLineStartOffset(startLineIndex);
CharSequence lineToTheLeft = chars.subSequence(startLineStartOffset, startPosition);
if (isBlockBegin(lineToTheLeft) && insertMatchingBrackets()) {
return;
}
if (isUnclosedComment(chars, startPosition, lineToTheLeft)) {
insertMatchingCloseComment();
} else {
textArea.replaceSelection(
"\n" + textArea.getIndenter().getCurrentIndentationOfLine(startLineIndex));
if (textArea.getIndenter().canOnlyAutoIndent()) {
// The other indenters all get a chance to fix the current line's indentation before
// suggesting an auto-indent level for this line.
// It's possible that not differentiating between these two cases when calling the
// indenter is a design error.
// It's also possible that allowing this code to modify lines other than the
// newly-inserted line is a design error.
// We certainly make it annoyingly hard for the user to override us even when they want
// to, though maybe if our indenters were better no-one would care?
textArea.getIndenter().fixIndentation();
} else if (fixIndentation) {
textArea.getIndenter().fixIndentationOnLine(startLineIndex);
textArea.getIndenter().fixIndentation();
} else {
new PCopyingIndenter(textArea).fixIndentation();
}
}
} finally {
textArea.getTextBuffer().getUndoBuffer().finishCompoundEdit();
}
}
// PSimpleIndenter has such a method but it's not exposed in the base class.
private boolean isBlockBegin(CharSequence lineToTheLeft) {
if (lineToTheLeft.length() == 0) {
return false;
}
char lastChar = lineToTheLeft.charAt(lineToTheLeft.length() - 1);
if (PBracketUtilities.isOpenBracket(lastChar) == false) {
return false;
}
char closeBracket = PBracketUtilities.getPartnerForBracket(lastChar);
if (textArea.getIndenter().isElectric(closeBracket) == false) {
return false;
}
return true;
}
private boolean insertMatchingBrackets() {
final int start = textArea.getSelectionStart();
final int end = textArea.getSelectionEnd();
int endLineIndex = textArea.getLineOfOffset(end);
int suffixPosition = textArea.getLineEndOffsetBeforeTerminator(endLineIndex);
String beforeInsertion = textArea.getTextBuffer().subSequence(0, start).toString();
String afterInsertion =
textArea
.getTextBuffer()
.subSequence(suffixPosition, textArea.getTextBuffer().length())
.toString();
String unmatchedOpenBrackets = getUnmatchedBrackets(beforeInsertion);
String unmatchedCloseBrackets = getUnmatchedBrackets(afterInsertion);
String reflectedCloseBrackets = PBracketUtilities.reflectBrackets(unmatchedCloseBrackets);
if (unmatchedOpenBrackets.startsWith(reflectedCloseBrackets) == false) {
return false;
}
String closingBrackets =
PBracketUtilities.reflectBrackets(
unmatchedOpenBrackets.substring(reflectedCloseBrackets.length()));
if (closingBrackets.length() == 0) {
return false;
}
String startLine = getLineTextAtOffset(start);
if (closingBrackets.endsWith("}") == false
|| textArea.getIndenter().isInNeedOfClosingSemicolon(startLine)) {
// TODO: "closingBrackets" is a bad name now it can have a semicolon on the end!
closingBrackets = closingBrackets + ";";
}
String candidateBlockContents =
textArea.getTextBuffer().subSequence(end, suffixPosition).toString();
String commonEnding = getCommonEnding(candidateBlockContents, closingBrackets);
String whitespace = getIndentationOfLineAtOffset(start);
// TODO: The newline inserter has no business thinking it knows how to increase the indent.
String prefix = "\n" + whitespace + textArea.getIndentationString();
String suffix = "\n" + whitespace + closingBrackets;
final int newCaretPosition = start + prefix.length();
textArea.replaceSelection(prefix);
// suffixPosition is invalidated by replaceSelection.
// But we can't swap the calls because replaceRange clears the selection.
int selectionSize = end - start;
suffixPosition -= selectionSize;
suffixPosition += prefix.length();
textArea.replaceRange(suffix, suffixPosition - commonEnding.length(), suffixPosition);
textArea.select(newCaretPosition, newCaretPosition);
return true;
}
/**
* Returns a string corresponding to the spaces and tabs found at the start of the line containing
* the given offset.
*/
private String getIndentationOfLineAtOffset(int offset) {
int lineNumber = textArea.getLineOfOffset(offset);
return textArea.getIndenter().getCurrentIndentationOfLine(lineNumber);
}