/*******************************************************************************
* Copyright (c) 2000, 2009 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
* Tom Eicher (Avaloq Evolution AG) - block selection mode
*******************************************************************************/
package org.eclipse.wst.jsdt.internal.ui.javaeditor;
import java.util.ResourceBundle;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.IRewriteTarget;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.ITextViewerExtension5;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.TextSelection;
import org.eclipse.jface.text.TextUtilities;
import org.eclipse.jface.text.source.ILineRange;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.jface.text.source.LineRange;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.widgets.Event;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.texteditor.IEditorStatusLine;
import org.eclipse.ui.texteditor.ITextEditor;
import org.eclipse.ui.texteditor.ITextEditorActionDefinitionIds;
import org.eclipse.ui.texteditor.TextEditorAction;
import org.eclipse.wst.jsdt.core.IJavaScriptProject;
import org.eclipse.wst.jsdt.core.IJavaScriptUnit;
import org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin;
import org.eclipse.wst.jsdt.internal.ui.javaeditor.IndentUtil.IndentResult;
/**
* Action for moving selected lines in a Java editor.
*
*/
public class JavaMoveLinesAction extends TextEditorAction {
/**
* State shared by the Move / Copy lines action quadruple.
*
*/
private static final class SharedState {
/** The compilation unit editor that all four actions operate on. */
public CompilationUnitEditor fEditor;
/**
* The indent token shared by all four actions.
*/
public IndentResult fResult= null;
/**
* Set to true before modifying the document, to false after.
*/
boolean fIsChanging= false;
/** <code>true</code> if a compound move / copy is going on. */
private boolean fEditInProgress= false;
/** The exit strategy that will detect the ending of a compound edit */
private final CompoundEditExitStrategy fExitStrategy;
public SharedState(CompilationUnitEditor editor) {
fEditor= editor;
fExitStrategy= new CompoundEditExitStrategy(new String[] {ITextEditorActionDefinitionIds.MOVE_LINES_UP, ITextEditorActionDefinitionIds.MOVE_LINES_DOWN, ITextEditorActionDefinitionIds.COPY_LINES_UP, ITextEditorActionDefinitionIds.COPY_LINES_DOWN});
fExitStrategy.addCompoundListener(new ICompoundEditListener() {
public void endCompoundEdit() {
SharedState.this.endCompoundEdit();
}
});
}
/**
* Ends the compound change.
*/
public void beginCompoundEdit() {
if (fEditInProgress || fEditor == null)
return;
fEditInProgress= true;
fExitStrategy.arm(fEditor.getViewer());
IRewriteTarget target= (IRewriteTarget)fEditor.getAdapter(IRewriteTarget.class);
if (target != null) {
target.beginCompoundChange();
}
}
/**
* Ends the compound change.
*/
public void endCompoundEdit() {
if (!fEditInProgress || fEditor == null)
return;
fExitStrategy.disarm();
IRewriteTarget target= (IRewriteTarget)fEditor.getAdapter(IRewriteTarget.class);
if (target != null) {
target.endCompoundChange();
}
fResult= null;
fEditInProgress= false;
}
}
/* keys */
/** Key for status message upon illegal move. <p>Value {@value}</p> */
/* state variables - define what this action does */
/** <code>true</code> if lines are shifted upwards, <code>false</code> otherwise. */
private final boolean fUpwards;
/** <code>true</code> if lines are to be copied instead of moved. */
private final boolean fCopy;
/** The shared state of the move/copy action quadruple. */
private final SharedState fSharedState;
/**
* Creates the quadruple of move and copy actions. The returned array contains
* the actions in the following order:
* [0] move up
* [1] move down
* [2] copy up (duplicate)
* [3] copy down (duplicate & select)
* @param bundle the resource bundle
* @param editor the editor
* @return the quadruple of actions
*/
public static JavaMoveLinesAction[] createMoveCopyActionSet(ResourceBundle bundle, CompilationUnitEditor editor) {
SharedState state= new SharedState(editor);
JavaMoveLinesAction[] actions= new JavaMoveLinesAction[4];
actions[0]= new JavaMoveLinesAction(bundle, "Editor.MoveLinesUp.", true, false, state); //$NON-NLS-1$
actions[1]= new JavaMoveLinesAction(bundle, "Editor.MoveLinesDown.", false, false, state); //$NON-NLS-1$
actions[2]= new JavaMoveLinesAction(bundle, "Editor.CopyLineUp.", true, true, state); //$NON-NLS-1$
actions[3]= new JavaMoveLinesAction(bundle, "Editor.CopyLineDown.", false, true, state); //$NON-NLS-1$
return actions;
}
/*
* @see org.eclipse.ui.texteditor.TextEditorAction#setEditor(org.eclipse.ui.texteditor.ITextEditor)
*/
public void setEditor(ITextEditor editor) {
Assert.isTrue(editor instanceof CompilationUnitEditor);
super.setEditor(editor);
if (fSharedState != null)
fSharedState.fEditor= (CompilationUnitEditor) editor;
}
/**
* Creates and initializes the action for the given text editor.
* The action configures its visual representation from the given resource
* bundle.
*
* @param bundle the resource bundle
* @param prefix a prefix to be prepended to the various resource keys
* (described in <code>ResourceAction</code> constructor), or <code>null</code> if none
* @param upwards <code>true</code>if the selected lines should be moved upwards,
* <code>false</code> if downwards
* @param copy if <code>true</code>, the action will copy lines instead of moving them
* @param state the shared state
* @see TextEditorAction#TextEditorAction(ResourceBundle, String, ITextEditor)
*/
private JavaMoveLinesAction(ResourceBundle bundle, String prefix, boolean upwards, boolean copy, SharedState state) {
super(bundle, prefix, state.fEditor);
fUpwards= upwards;
fCopy= copy;
fSharedState= state;
update();
}
/**
* Checks if <code>selection</code> is contained by the visible region of <code>viewer</code>.
* As a special case, a selection is considered contained even if it extends over the visible
* region, but the extension stays on a partially contained line and contains only white space.
*
* @param selection the selection to be checked
* @param viewer the viewer displaying a visible region of <code>selection</code>'s document.
* @return <code>true</code>, if <code>selection</code> is contained, <code>false</code> otherwise.
*/
private boolean containedByVisibleRegion(ITextSelection selection, ISourceViewer viewer) {
int min= selection.getOffset();
int max= min + selection.getLength();
IDocument document= viewer.getDocument();
IRegion visible;
if (viewer instanceof ITextViewerExtension5)
visible= ((ITextViewerExtension5) viewer).getModelCoverage();
else
visible= viewer.getVisibleRegion();
int visOffset= visible.getOffset();
try {
if (visOffset > min) {
if (document.getLineOfOffset(visOffset) != selection.getStartLine())
return false;
if (!isWhitespace(document.get(min, visOffset - min))) {
showStatus();
return false;
}
}
int visEnd= visOffset + visible.getLength();
if (visEnd < max) {
if (document.getLineOfOffset(visEnd) != selection.getEndLine())
return false;
if (!isWhitespace(document.get(visEnd, max - visEnd))) {
showStatus();
return false;
}
}
return true;
} catch (BadLocationException e) {
}
return false;
}
/**
* Given a selection on a document, computes the lines fully or partially covered by
* <code>selection</code>. A line in the document is considered covered if
* <code>selection</code> comprises any characters on it, including the terminating delimiter.
* <p>Note that the last line in a selection is not considered covered if the selection only
* comprises the line delimiter at its beginning (that is considered part of the second last
* line).
* As a special case, if the selection is empty, a line is considered covered if the caret is
* at any position in the line, including between the delimiter and the start of the line. The
* line containing the delimiter is not considered covered in that case.
* </p>
*
* @param document the document <code>selection</code> refers to
* @param selection a selection on <code>document</code>
* @param viewer the <code>ISourceViewer</code> displaying <code>document</code>
* @return a selection describing the range of lines (partially) covered by
* <code>selection</code>, without any terminating line delimiters
* @throws BadLocationException if the selection is out of bounds (when the underlying document has changed during the call)
*/
private ITextSelection getMovingSelection(IDocument document, ITextSelection selection, ISourceViewer viewer) throws BadLocationException {
int low= document.getLineOffset(selection.getStartLine());
int endLine= selection.getEndLine();
int high= document.getLineOffset(endLine) + document.getLineLength(endLine);
// get everything up to last line without its delimiter
String delim= document.getLineDelimiter(endLine);
if (delim != null)
high -= delim.length();
return new TextSelection(document, low, high - low);
}
/**
* Computes the region of the skipped line given the text block to be moved. If
* <code>fUpwards</code> is <code>true</code>, the line above <code>selection</code>
* is selected, otherwise the line below.
*
* @param document the document <code>selection</code> refers to
* @param selection the selection on <code>document</code> that will be moved.
* @return the region comprising the line that <code>selection</code> will be moved over, without its terminating delimiter.
*/
private ITextSelection getSkippedLine(IDocument document, ITextSelection selection) {
int skippedLineN= (fUpwards ? selection.getStartLine() - 1 : selection.getEndLine() + 1);
if (skippedLineN > document.getNumberOfLines() || (!fCopy && (skippedLineN < 0 || skippedLineN == document.getNumberOfLines())))
return null;
try {
if (fCopy && skippedLineN == -1)
skippedLineN= 0;
IRegion line= document.getLineInformation(skippedLineN);
return new TextSelection(document, line.getOffset(), line.getLength());
} catch (BadLocationException e) {
// only happens on concurrent modifications
return null;
}
}
/**
* Checks for white space in a string.
*
* @param string the string to be checked or <code>null</code>
* @return <code>true</code> if <code>string</code> contains only white space or is
* <code>null</code>, <code>false</code> otherwise
*/
private boolean isWhitespace(String string) {
return string == null ? true : string.trim().length() == 0;
}
/*
* @see org.eclipse.jface.action.IAction#run()
*/
public void runWithEvent(Event event) {
// get involved objects
if (fSharedState.fEditor == null)
return;
if (!validateEditorInputState())
return;
ISourceViewer viewer= fSharedState.fEditor.getViewer();
if (viewer == null)
return;
IDocument document= viewer.getDocument();
if (document == null)
return;
StyledText widget= viewer.getTextWidget();
if (widget == null)
return;
// get selection
ITextSelection sel= (ITextSelection) viewer.getSelectionProvider().getSelection();
if (sel.isEmpty())
return;
ITextSelection skippedLine= getSkippedLine(document, sel);
if (skippedLine == null)
return;
try {
ITextSelection movingArea= getMovingSelection(document, sel, viewer);
// if either the skipped line or the moving lines are outside the widget's
// visible area, bail out
if (!containedByVisibleRegion(movingArea, viewer) || !containedByVisibleRegion(skippedLine, viewer))
return;
// get the content to be moved around: the moving (selected) area and the skipped line
String moving= movingArea.getText();
String skipped= skippedLine.getText();
if (moving == null || skipped == null || document.getLength() == 0)
return;
String delim;
String insertion;
int offset;
if (fUpwards) {
delim= document.getLineDelimiter(skippedLine.getEndLine());
if (fCopy) {
delim= TextUtilities.getDefaultLineDelimiter(document);
insertion= moving + delim;
offset= movingArea.getOffset();
} else {
Assert.isNotNull(delim);
insertion= moving + delim + skipped;
offset= skippedLine.getOffset();
}
} else {
delim= document.getLineDelimiter(movingArea.getEndLine());
if (fCopy) {
if (delim == null) {
delim= TextUtilities.getDefaultLineDelimiter(document);
insertion= delim + moving;
} else
insertion= moving + delim;
offset= skippedLine.getOffset();
} else {
Assert.isNotNull(delim);
insertion= skipped + delim + moving;
offset= movingArea.getOffset();
}
}
int lenght= fCopy ? 0 : insertion.length();
// modify the document
ILineRange selectionBefore= getLineRange(document, movingArea);
if (fCopy)
fSharedState.endCompoundEdit();
fSharedState.beginCompoundEdit();
fSharedState.fIsChanging= true;
document.replace(offset, lenght, insertion);
ILineRange selectionAfter;
if (fUpwards && fCopy)
selectionAfter= selectionBefore;
else if (fUpwards)
selectionAfter= new LineRange(selectionBefore.getStartLine() - 1, selectionBefore.getNumberOfLines());
else if (fCopy)
selectionAfter= new LineRange(selectionBefore.getStartLine() + selectionBefore.getNumberOfLines(), selectionBefore.getNumberOfLines());
else
selectionAfter= new LineRange(selectionBefore.getStartLine() + 1, selectionBefore.getNumberOfLines());
fSharedState.fResult= IndentUtil.indentLines(document, selectionAfter, getProject(), fSharedState.fResult);
// move the selection along
IRegion region= getRegion(document, selectionAfter);
selectAndReveal(viewer, region.getOffset(), region.getLength());
} catch (BadLocationException x) {
// won't happen without concurrent modification - bail out
return;
} finally {
fSharedState.fIsChanging= false;
if (fCopy)
fSharedState.endCompoundEdit();
}
}
private IJavaScriptProject getProject() {
IEditorInput editorInput= fSharedState.fEditor.getEditorInput();
IJavaScriptUnit unit= JavaScriptPlugin.getDefault().getWorkingCopyManager().getWorkingCopy(editorInput);
if (unit != null)
return unit.getJavaScriptProject();
return null;
}
private ILineRange getLineRange(IDocument document, ITextSelection selection) throws BadLocationException {
final int offset= selection.getOffset();
int startLine= document.getLineOfOffset(offset);
int endOffset= offset + selection.getLength();
int endLine= document.getLineOfOffset(endOffset);
final int nLines= endLine - startLine + 1;
return new LineRange(startLine, nLines);
}
private IRegion getRegion(IDocument document, ILineRange lineRange) throws BadLocationException {
final int startLine= lineRange.getStartLine();
int offset= document.getLineOffset(startLine);
final int numberOfLines= lineRange.getNumberOfLines();
if (numberOfLines < 1)
return new Region(offset, 0);
int endLine = startLine + numberOfLines - 1;
int endOffset;
if (fSharedState.fEditor.isBlockSelectionModeEnabled()) {
// in column mode, don't select the last delimiter as we count an
// empty selected line
IRegion endLineInfo = document.getLineInformation(endLine);
endOffset = endLineInfo.getOffset() + endLineInfo.getLength();
}
else {
endOffset = document.getLineOffset(endLine) + document.getLineLength(endLine);
}
return new Region(offset, endOffset - offset);
}
/**
* Performs similar to AbstractTextEditor.selectAndReveal, but does not update
* the viewers highlight area.
*
* @param viewer the viewer that we want to select on
* @param offset the offset of the selection
* @param length the length of the selection
*/
private void selectAndReveal(ITextViewer viewer, int offset, int length) {
// invert selection to avoid jumping to the end of the selection in st.showSelection()
viewer.setSelectedRange(offset + length, -length);
//viewer.revealRange(offset, length); // will trigger jumping
StyledText st= viewer.getTextWidget();
if (st != null)
st.showSelection(); // only minimal scrolling
}
/**
* Displays information in the status line why a line move is not possible
*/
private void showStatus() {
IEditorStatusLine status= (IEditorStatusLine) fSharedState.fEditor.getAdapter(IEditorStatusLine.class);
if (status == null)
return;
status.setMessage(false, JavaEditorMessages.Editor_MoveLines_IllegalMove_status, null);
}
/*
* @see org.eclipse.ui.texteditor.IUpdate#update()
*/
public void update() {
super.update();
if (isEnabled())
setEnabled(canModifyEditor());
}
}