net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/actions/IndentAction.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2004 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpdt.internal.ui.actions;
  12
  13 import java.util.ResourceBundle;
  14
  15 import net.sourceforge.phpdt.core.JavaCore;
  16 import net.sourceforge.phpdt.core.formatter.DefaultCodeFormatterConstants;
  17 import net.sourceforge.phpdt.internal.ui.text.IPHPPartitions;
  18 import net.sourceforge.phpdt.internal.ui.text.JavaHeuristicScanner;
  19 import net.sourceforge.phpdt.internal.ui.text.JavaIndenter;
  20 import net.sourceforge.phpdt.internal.ui.text.SmartBackspaceManager;
  21 import net.sourceforge.phpdt.internal.ui.text.SmartBackspaceManager.UndoSpec;
  22 import net.sourceforge.phpdt.internal.ui.text.phpdoc.JavaDocAutoIndentStrategy;
  23 import net.sourceforge.phpdt.ui.PreferenceConstants;
  24 import net.sourceforge.phpeclipse.PHPeclipsePlugin;
  25 import net.sourceforge.phpeclipse.phpeditor.PHPEditor;
  26
  27 import org.eclipse.core.runtime.IStatus;
  28 import org.eclipse.core.runtime.Status;
  29 import org.eclipse.jface.text.Assert;
  30 import org.eclipse.jface.text.BadLocationException;
  31 import org.eclipse.jface.text.DocumentCommand;
  32 import org.eclipse.jface.text.IDocument;
  33 import org.eclipse.jface.text.IRegion;
  34 import org.eclipse.jface.text.IRewriteTarget;
  35 import org.eclipse.jface.text.ITextSelection;
  36 import org.eclipse.jface.text.ITypedRegion;
  37 import org.eclipse.jface.text.Position;
  38 import org.eclipse.jface.text.Region;
  39 import org.eclipse.jface.text.TextSelection;
  40 import org.eclipse.jface.text.TextUtilities;
  41 import org.eclipse.jface.text.source.ISourceViewer;
  42 import org.eclipse.jface.viewers.ISelection;
  43 import org.eclipse.jface.viewers.ISelectionProvider;
  44 import org.eclipse.swt.custom.BusyIndicator;
  45 import org.eclipse.swt.widgets.Display;
  46 import org.eclipse.text.edits.MalformedTreeException;
  47 import org.eclipse.text.edits.ReplaceEdit;
  48 import org.eclipse.text.edits.TextEdit;
  49 import org.eclipse.ui.IEditorInput;
  50 import org.eclipse.ui.texteditor.AbstractDecoratedTextEditorPreferenceConstants;
  51 import org.eclipse.ui.texteditor.IDocumentProvider;
  52 import org.eclipse.ui.texteditor.ITextEditor;
  53 import org.eclipse.ui.texteditor.ITextEditorExtension3;
  54 import org.eclipse.ui.texteditor.TextEditorAction;
  55
  56 /**
  57  * Indents a line or range of lines in a Java document to its correct position.
  58  * No complete AST must be present, the indentation is computed using
  59  * heuristics. The algorith used is fast for single lines, but does not store
  60  * any information and therefore not so efficient for large line ranges.
  61  *
  62  * @see net.sourceforge.phpdt.internal.ui.text.JavaHeuristicScanner
  63  * @see net.sourceforge.phpdt.internal.ui.text.JavaIndenter
  64  * @since 3.0
  65  */
  66 public class IndentAction extends TextEditorAction {
  67
  68         /** The caret offset after an indent operation. */
  69         private int fCaretOffset;
  70
  71         /**
  72          * Whether this is the action invoked by TAB. When <code>true</code>,
  73          * indentation behaves differently to accomodate normal TAB operation.
  74          */
  75         private final boolean fIsTabAction;
  76
  77         /**
  78          * Creates a new instance.
  79          *
  80          * @param bundle
  81          *            the resource bundle
  82          * @param prefix
  83          *            the prefix to use for keys in <code>bundle</code>
  84          * @param editor
  85          *            the text editor
  86          * @param isTabAction
  87          *            whether the action should insert tabs if over the indentation
  88          */
  89         public IndentAction(ResourceBundle bundle, String prefix,
  90                         ITextEditor editor, boolean isTabAction) {
  91                 super(bundle, prefix, editor);
  92                 fIsTabAction = isTabAction;
  93         }
  94
  95         /*
  96          * @see org.eclipse.jface.action.Action#run()
  97          */
  98         public void run() {
  99                 // update has been called by the framework
 100                 if (!isEnabled() || !validateEditorInputState())
 101                         return;
 102
 103                 ITextSelection selection = getSelection();
 104                 final IDocument document = getDocument();
 105
 106                 if (document != null) {
 107
 108                         final int offset = selection.getOffset();
 109                         final int length = selection.getLength();
 110                         final Position end = new Position(offset + length);
 111                         final int firstLine, nLines;
 112                         fCaretOffset = -1;
 113
 114                         try {
 115                                 document.addPosition(end);
 116                                 firstLine = document.getLineOfOffset(offset);
 117                                 // check for marginal (zero-length) lines
 118                                 int minusOne = length == 0 ? 0 : 1;
 119                                 nLines = document.getLineOfOffset(offset + length - minusOne)
 120                                                 - firstLine + 1;
 121                         } catch (BadLocationException e) {
 122                                 // will only happen on concurrent modification
 123                                 PHPeclipsePlugin.log(new Status(IStatus.ERROR, PHPeclipsePlugin
 124                                                 .getPluginId(), IStatus.OK, "", e)); //$NON-NLS-1$
 125                                 return;
 126                         }
 127
 128                         Runnable runnable = new Runnable() {
 129                                 public void run() {
 130                                         IRewriteTarget target = (IRewriteTarget) getTextEditor()
 131                                                         .getAdapter(IRewriteTarget.class);
 132                                         if (target != null) {
 133                                                 target.beginCompoundChange();
 134                                                 target.setRedraw(false);
 135                                         }
 136
 137                                         try {
 138                                                 JavaHeuristicScanner scanner = new JavaHeuristicScanner(
 139                                                                 document);
 140                                                 JavaIndenter indenter = new JavaIndenter(document,
 141                                                                 scanner);
 142                                                 boolean hasChanged = false;
 143                                                 for (int i = 0; i < nLines; i++) {
 144                                                         hasChanged |= indentLine(document, firstLine + i,
 145                                                                         offset, indenter, scanner);
 146                                                 }
 147
 148                                                 // update caret position: move to new position when
 149                                                 // indenting just one line
 150                                                 // keep selection when indenting multiple
 151                                                 int newOffset, newLength;
 152                                                 if (fIsTabAction) {
 153                                                         newOffset = fCaretOffset;
 154                                                         newLength = 0;
 155                                                 } else if (nLines > 1) {
 156                                                         newOffset = offset;
 157                                                         newLength = end.getOffset() - offset;
 158                                                 } else {
 159                                                         newOffset = fCaretOffset;
 160                                                         newLength = 0;
 161                                                 }
 162
 163                                                 // always reset the selection if anything was replaced
 164                                                 // but not when we had a singleline nontab invocation
 165                                                 if (newOffset != -1
 166                                                                 && (hasChanged || newOffset != offset || newLength != length))
 167                                                         selectAndReveal(newOffset, newLength);
 168
 169                                                 document.removePosition(end);
 170                                         } catch (BadLocationException e) {
 171                                                 // will only happen on concurrent modification
 172                                                 PHPeclipsePlugin.log(new Status(IStatus.ERROR,
 173                                                                 PHPeclipsePlugin.getPluginId(), IStatus.OK,
 174                                                                 "ConcurrentModification in IndentAction", e)); //$NON-NLS-1$
 175
 176                                         } finally {
 177
 178                                                 if (target != null) {
 179                                                         target.endCompoundChange();
 180                                                         target.setRedraw(true);
 181                                                 }
 182                                         }
 183                                 }
 184                         };
 185
 186                         if (nLines > 50) {
 187                                 Display display = getTextEditor().getEditorSite()
 188                                                 .getWorkbenchWindow().getShell().getDisplay();
 189                                 BusyIndicator.showWhile(display, runnable);
 190                         } else
 191                                 runnable.run();
 192
 193                 }
 194         }
 195
 196         /**
 197          * Selects the given range on the editor.
 198          *
 199          * @param newOffset
 200          *            the selection offset
 201          * @param newLength
 202          *            the selection range
 203          */
 204         private void selectAndReveal(int newOffset, int newLength) {
 205                 Assert.isTrue(newOffset >= 0);
 206                 Assert.isTrue(newLength >= 0);
 207                 ITextEditor editor = getTextEditor();
 208                 if (editor instanceof PHPEditor) {
 209                         ISourceViewer viewer = ((PHPEditor) editor).getViewer();
 210                         if (viewer != null)
 211                                 viewer.setSelectedRange(newOffset, newLength);
 212                 } else
 213                         // this is too intrusive, but will never get called anyway
 214                         getTextEditor().selectAndReveal(newOffset, newLength);
 215
 216         }
 217
 218         /**
 219          * Indents a single line using the java heuristic scanner. Javadoc and
 220          * multiline comments are indented as specified by the
 221          * <code>JavaDocAutoIndentStrategy</code>.
 222          *
 223          * @param document
 224          *            the document
 225          * @param line
 226          *            the line to be indented
 227          * @param caret
 228          *            the caret position
 229          * @param indenter
 230          *            the java indenter
 231          * @param scanner
 232          *            the heuristic scanner
 233          * @return <code>true</code> if <code>document</code> was modified,
 234          *         <code>false</code> otherwise
 235          * @throws BadLocationException
 236          *             if the document got changed concurrently
 237          */
 238         private boolean indentLine(IDocument document, int line, int caret,
 239                         JavaIndenter indenter, JavaHeuristicScanner scanner)
 240                         throws BadLocationException {
 241                 IRegion currentLine = document.getLineInformation(line);
 242                 int offset = currentLine.getOffset();
 243                 int wsStart = offset; // where we start searching for non-WS; after
 244                                                                 // the "//" in single line comments
 245
 246                 String indent = null;
 247                 if (offset < document.getLength()) {
 248                         ITypedRegion partition = TextUtilities.getPartition(document,
 249                                         IPHPPartitions.PHP_PARTITIONING, offset, true);
 250                         String type = partition.getType();
 251                         if (type.equals(IPHPPartitions.PHP_PHPDOC_COMMENT)
 252                                         || type.equals(IPHPPartitions.PHP_MULTILINE_COMMENT)) {
 253
 254                                 // TODO this is a hack
 255                                 // what I want to do
 256                                 // new JavaDocAutoIndentStrategy().indentLineAtOffset(document,
 257                                 // offset);
 258                                 // return;
 259
 260                                 int start = 0;
 261                                 if (line > 0) {
 262
 263                                         IRegion previousLine = document
 264                                                         .getLineInformation(line - 1);
 265                                         start = previousLine.getOffset() + previousLine.getLength();
 266                                 }
 267
 268                                 DocumentCommand command = new DocumentCommand() {
 269                                 };
 270                                 command.text = "\n"; //$NON-NLS-1$
 271                                 command.offset = start;
 272                                 new JavaDocAutoIndentStrategy(IPHPPartitions.PHP_PARTITIONING)
 273                                                 .customizeDocumentCommand(document, command);
 274                                 int to = 1;
 275                                 while (to < command.text.length()
 276                                                 && Character.isWhitespace(command.text.charAt(to)))
 277                                         to++;
 278                                 indent = command.text.substring(1, to);
 279
 280 // omit Java style
 281 //                      } else if (!fIsTabAction && partition.getOffset() == offset
 282 //                                      && type.equals(IPHPPartitions.PHP_SINGLELINE_COMMENT)) {
 283 //
 284 //                              // line comment starting at position 0 -> indent inside
 285 //                              int slashes = 2;
 286 //                              while (slashes < document.getLength() - 1
 287 //                                              && document.get(offset + slashes, 2).equals("//")) //$NON-NLS-1$
 288 //                                      slashes += 2;
 289 //
 290 //                              wsStart = offset + slashes;
 291 //
 292 //                              StringBuffer computed = indenter.computeIndentation(offset);
 293 //                              int tabSize = PHPeclipsePlugin
 294 //                                              .getDefault()
 295 //                                              .getPreferenceStore()
 296 //                                              .getInt(
 297 //                                                              AbstractDecoratedTextEditorPreferenceConstants.EDITOR_TAB_WIDTH);
 298 //                              while (slashes > 0 && computed.length() > 0) {
 299 //                                      char c = computed.charAt(0);
 300 //                                      if (c == '\t')
 301 //                                              if (slashes > tabSize)
 302 //                                                      slashes -= tabSize;
 303 //                                              else
 304 //                                                      break;
 305 //                                      else if (c == ' ')
 306 //                                              slashes--;
 307 //                                      else
 308 //                                              break;
 309 //
 310 //                                      computed.deleteCharAt(0);
 311 //                              }
 312 //
 313 //                              indent = document.get(offset, wsStart - offset) + computed;
 314
 315                         }
 316                 }
 317
 318                 // standard java indentation
 319                 if (indent == null) {
 320                         StringBuffer computed = indenter.computeIndentation(offset);
 321                         if (computed != null)
 322                                 indent = computed.toString();
 323                         else
 324                                 //indent = new String();
 325                                 return true; // prevent affecting html part
 326                 }
 327
 328                 // change document:
 329                 // get current white space
 330                 int lineLength = currentLine.getLength();
 331                 int end = scanner.findNonWhitespaceForwardInAnyPartition(wsStart,
 332                                 offset + lineLength);
 333                 if (end == JavaHeuristicScanner.NOT_FOUND)
 334                         end = offset + lineLength;
 335                 int length = end - offset;
 336                 String currentIndent = document.get(offset, length);
 337
 338                 // if we are right before the text start / line end, and already after
 339                 // the insertion point
 340                 // then just insert a tab.
 341                 if (fIsTabAction && caret == end
 342                                 && whiteSpaceLength(currentIndent) >= whiteSpaceLength(indent)) {
 343                         String tab = getTabEquivalent();
 344                         document.replace(caret, 0, tab);
 345                         fCaretOffset = caret + tab.length();
 346                         return true;
 347                 }
 348
 349                 // set the caret offset so it can be used when setting the selection
 350                 if (caret >= offset && caret <= end)
 351                         fCaretOffset = offset + indent.length();
 352                 else
 353                         fCaretOffset = -1;
 354
 355                 // only change the document if it is a real change
 356                 if (!indent.equals(currentIndent)) {
 357                         String deletedText = document.get(offset, length);
 358                         document.replace(offset, length, indent);
 359
 360                         if (fIsTabAction
 361                                         && indent.length() > currentIndent.length()
 362                                         && PHPeclipsePlugin.getDefault().getPreferenceStore()
 363                                                         .getBoolean(
 364                                                                         PreferenceConstants.EDITOR_SMART_BACKSPACE)) {
 365                                 ITextEditor editor = getTextEditor();
 366                                 if (editor != null) {
 367                                         final SmartBackspaceManager manager = (SmartBackspaceManager) editor
 368                                                         .getAdapter(SmartBackspaceManager.class);
 369                                         if (manager != null) {
 370                                                 try {
 371                                                         // restore smart portion
 372                                                         ReplaceEdit smart = new ReplaceEdit(offset, indent
 373                                                                         .length(), deletedText);
 374
 375                                                         final UndoSpec spec = new UndoSpec(offset
 376                                                                         + indent.length(), new Region(caret, 0),
 377                                                                         new TextEdit[] { smart }, 2, null);
 378                                                         manager.register(spec);
 379                                                 } catch (MalformedTreeException e) {
 380                                                         // log & ignore
 381                                                         PHPeclipsePlugin.log(new Status(IStatus.ERROR,
 382                                                                         PHPeclipsePlugin.getPluginId(), IStatus.OK,
 383                                                                         "Illegal smart backspace action", e)); //$NON-NLS-1$
 384                                                 }
 385                                         }
 386                                 }
 387                         }
 388
 389                         return true;
 390                 } else
 391                         return false;
 392         }
 393
 394         /**
 395          * Returns the size in characters of a string. All characters count one,
 396          * tabs count the editor's preference for the tab display
 397          *
 398          * @param indent
 399          *            the string to be measured.
 400          * @return
 401          */
 402         private int whiteSpaceLength(String indent) {
 403                 if (indent == null)
 404                         return 0;
 405                 else {
 406                         int size = 0;
 407                         int l = indent.length();
 408                         int tabSize = PHPeclipsePlugin
 409                                         .getDefault()
 410                                         .getPreferenceStore()
 411                                         .getInt(
 412                                                         AbstractDecoratedTextEditorPreferenceConstants.EDITOR_TAB_WIDTH);
 413
 414                         for (int i = 0; i < l; i++)
 415                                 size += indent.charAt(i) == '\t' ? tabSize : 1;
 416                         return size;
 417                 }
 418         }
 419
 420         /**
 421          * Returns a tab equivalent, either as a tab character or as spaces,
 422          * depending on the editor and formatter preferences.
 423          *
 424          * @return a string representing one tab in the editor, never
 425          *         <code>null</code>
 426          */
 427         private String getTabEquivalent() {
 428                 String tab;
 429                 if (PHPeclipsePlugin.getDefault().getPreferenceStore().getBoolean(
 430                                 PreferenceConstants.EDITOR_SPACES_FOR_TABS)) {
 431                         int size = JavaCore.getPlugin().getPluginPreferences().getInt(
 432                                         DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE);
 433                         StringBuffer buf = new StringBuffer();
 434                         for (int i = 0; i < size; i++)
 435                                 buf.append(' ');
 436                         tab = buf.toString();
 437                 } else
 438                         tab = "\t"; //$NON-NLS-1$
 439
 440                 return tab;
 441         }
 442
 443         /**
 444          * Returns the editor's selection provider.
 445          *
 446          * @return the editor's selection provider or <code>null</code>
 447          */
 448         private ISelectionProvider getSelectionProvider() {
 449                 ITextEditor editor = getTextEditor();
 450                 if (editor != null) {
 451                         return editor.getSelectionProvider();
 452                 }
 453                 return null;
 454         }
 455
 456         /*
 457          * @see org.eclipse.ui.texteditor.IUpdate#update()
 458          */
 459         public void update() {
 460                 super.update();
 461
 462                 if (isEnabled())
 463                         if (fIsTabAction)
 464                                 setEnabled(canModifyEditor() && isSmartMode()
 465                                                 && isValidSelection());
 466                         else
 467                                 setEnabled(canModifyEditor() && !getSelection().isEmpty());
 468         }
 469
 470         /**
 471          * Returns if the current selection is valid, i.e. whether it is empty and
 472          * the caret in the whitespace at the start of a line, or covers multiple
 473          * lines.
 474          *
 475          * @return <code>true</code> if the selection is valid for an indent
 476          *         operation
 477          */
 478         private boolean isValidSelection() {
 479                 ITextSelection selection = getSelection();
 480                 if (selection.isEmpty())
 481                         return false;
 482
 483                 int offset = selection.getOffset();
 484                 int length = selection.getLength();
 485
 486                 IDocument document = getDocument();
 487                 if (document == null)
 488                         return false;
 489
 490                 try {
 491                         IRegion firstLine = document.getLineInformationOfOffset(offset);
 492                         int lineOffset = firstLine.getOffset();
 493
 494                         // either the selection has to be empty and the caret in the WS at
 495                         // the line start
 496                         // or the selection has to extend over multiple lines
 497                         if (length == 0)
 498                                 return document.get(lineOffset, offset - lineOffset).trim()
 499                                                 .length() == 0;
 500                         else
 501                                 // return lineOffset + firstLine.getLength() < offset + length;
 502                                 return false; // only enable for empty selections for now
 503
 504                 } catch (BadLocationException e) {
 505                 }
 506
 507                 return false;
 508         }
 509
 510         /**
 511          * Returns the smart preference state.
 512          *
 513          * @return <code>true</code> if smart mode is on, <code>false</code>
 514          *         otherwise
 515          */
 516         private boolean isSmartMode() {
 517                 ITextEditor editor = getTextEditor();
 518
 519                 if (editor instanceof ITextEditorExtension3)
 520                         return ((ITextEditorExtension3) editor).getInsertMode() == ITextEditorExtension3.SMART_INSERT;
 521
 522                 return false;
 523         }
 524
 525         /**
 526          * Returns the document currently displayed in the editor, or
 527          * <code>null</code> if none can be obtained.
 528          *
 529          * @return the current document or <code>null</code>
 530          */
 531         private IDocument getDocument() {
 532
 533                 ITextEditor editor = getTextEditor();
 534                 if (editor != null) {
 535
 536                         IDocumentProvider provider = editor.getDocumentProvider();
 537                         IEditorInput input = editor.getEditorInput();
 538                         if (provider != null && input != null)
 539                                 return provider.getDocument(input);
 540
 541                 }
 542                 return null;
 543         }
 544
 545         /**
 546          * Returns the selection on the editor or an invalid selection if none can
 547          * be obtained. Returns never <code>null</code>.
 548          *
 549          * @return the current selection, never <code>null</code>
 550          */
 551         private ITextSelection getSelection() {
 552                 ISelectionProvider provider = getSelectionProvider();
 553                 if (provider != null) {
 554
 555                         ISelection selection = provider.getSelection();
 556                         if (selection instanceof ITextSelection)
 557                                 return (ITextSelection) selection;
 558                 }
 559
 560                 // null object
 561                 return TextSelection.emptySelection();
 562         }
 563
 564 }