/*******************************************************************************
 * Copyright (c) 2000, 2011 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
 *******************************************************************************/
package org.eclipse.jdt.internal.corext.fix;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Map;
import java.util.Set;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.TextLayout;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Link;
import org.eclipse.swt.widgets.Shell;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.Status;
import org.eclipse.core.runtime.SubProgressMonitor;
import org.eclipse.core.runtime.preferences.DefaultScope;
import org.eclipse.core.runtime.preferences.IEclipsePreferences;
import org.eclipse.core.runtime.preferences.InstanceScope;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.ProjectScope;

import org.eclipse.core.filebuffers.FileBuffers;
import org.eclipse.core.filebuffers.ITextFileBuffer;
import org.eclipse.core.filebuffers.ITextFileBufferManager;
import org.eclipse.core.filebuffers.LocationKind;

import org.eclipse.text.edits.MalformedTreeException;
import org.eclipse.text.edits.TextEdit;
import org.eclipse.text.edits.UndoEdit;

import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.window.Window;

import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.BadPositionCategoryException;
import org.eclipse.jface.text.DefaultPositionUpdater;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IDocumentExtension4;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.Region;

import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.dialogs.PreferencesUtil;

import org.eclipse.ltk.core.refactoring.Change;
import org.eclipse.ltk.core.refactoring.CompositeChange;
import org.eclipse.ltk.core.refactoring.IRefactoringCoreStatusCodes;
import org.eclipse.ltk.core.refactoring.IUndoManager;
import org.eclipse.ltk.core.refactoring.NullChange;
import org.eclipse.ltk.core.refactoring.PerformChangeOperation;
import org.eclipse.ltk.core.refactoring.RefactoringCore;
import org.eclipse.ltk.core.refactoring.RefactoringStatus;
import org.eclipse.ltk.core.refactoring.TextFileChange;
import org.eclipse.ltk.ui.refactoring.RefactoringUI;

import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.dom.ASTParser;
import org.eclipse.jdt.core.dom.CompilationUnit;

import org.eclipse.jdt.internal.corext.fix.CleanUpRefactoring.CleanUpChange;
import org.eclipse.jdt.internal.corext.refactoring.util.RefactoringASTParser;
import org.eclipse.jdt.internal.corext.util.Messages;

import org.eclipse.jdt.ui.JavaUI;
import org.eclipse.jdt.ui.SharedASTProvider;
import org.eclipse.jdt.ui.cleanup.CleanUpContext;
import org.eclipse.jdt.ui.cleanup.CleanUpOptions;
import org.eclipse.jdt.ui.cleanup.CleanUpRequirements;
import org.eclipse.jdt.ui.cleanup.ICleanUp;

import org.eclipse.jdt.internal.ui.JavaPlugin;
import org.eclipse.jdt.internal.ui.actions.ActionUtil;
import org.eclipse.jdt.internal.ui.dialogs.OptionalMessageDialog;
import org.eclipse.jdt.internal.ui.fix.IMultiLineCleanUp.MultiLineCleanUpContext;
import org.eclipse.jdt.internal.ui.fix.MapCleanUpOptions;
import org.eclipse.jdt.internal.ui.javaeditor.saveparticipant.IPostSaveListener;
import org.eclipse.jdt.internal.ui.preferences.BulletListBlock;
import org.eclipse.jdt.internal.ui.preferences.SaveParticipantPreferencePage;

public class CleanUpPostSaveListener implements IPostSaveListener {

	private static class CleanUpSaveUndo extends TextFileChange {

		private final IFile fFile;
		private final UndoEdit[] fUndos;
		private final long fDocumentStamp;
		private final long fFileStamp;

		public CleanUpSaveUndo(String name, IFile file, UndoEdit[] undos, long documentStamp, long fileStamp) {
			super(name, file);
			Assert.isNotNull(undos);

			fDocumentStamp= documentStamp;
			fFileStamp= fileStamp;
			fFile= file;
			fUndos= undos;
		}

		@Override
		public final boolean needsSaving() {
			return true;
		}

		/**
		 * {@inheritDoc}
		 */
		@Override
		public Change perform(IProgressMonitor pm) throws CoreException {
			if (isValid(pm).hasFatalError())
				return new NullChange();

			if (pm == null)
				pm= new NullProgressMonitor();

			ITextFileBufferManager manager= FileBuffers.getTextFileBufferManager();
			pm.beginTask("", 2); //$NON-NLS-1$
			ITextFileBuffer buffer= null;
			try {
				manager.connect(fFile.getFullPath(), LocationKind.IFILE, new SubProgressMonitor(pm, 1));
				buffer= manager.getTextFileBuffer(fFile.getFullPath(), LocationKind.IFILE);
				
				final IDocument document= buffer.getDocument();
				final long oldFileValue= fFile.getModificationStamp();
				final LinkedList<UndoEdit> undoEditCollector= new LinkedList<UndoEdit>();
				final long[] oldDocValue= new long[1];
				final boolean[] setContentStampSuccess= { false };
				
				if (! buffer.isSynchronizationContextRequested()) {
					performEdit(document, oldFileValue, undoEditCollector, oldDocValue, setContentStampSuccess);
					
				} else {
					ITextFileBufferManager fileBufferManager= FileBuffers.getTextFileBufferManager();
					
					class UIRunnable implements Runnable {
						public boolean fDone;
						public Exception fException;
						
						public void run() {
							synchronized (this) {
								try {
									performEdit(document, oldFileValue, undoEditCollector, oldDocValue, setContentStampSuccess);
								} catch (BadLocationException e) {
									fException= e;
								} catch (MalformedTreeException e) {
									fException= e;
								} catch (CoreException e) {
									fException= e;
								} finally {
									fDone= true;
									notifyAll();
								}
							}
						}
					}
					UIRunnable runnable= new UIRunnable();
					
					synchronized (runnable) {
						fileBufferManager.execute(runnable);
						while (! runnable.fDone) {
							try {
								runnable.wait(500);
							} catch (InterruptedException x) {
							}
						}
					}
					
					if (runnable.fException != null) {
						if (runnable.fException instanceof BadLocationException) {
							throw (BadLocationException) runnable.fException;
						} else if (runnable.fException instanceof MalformedTreeException) {
							throw (MalformedTreeException) runnable.fException;
						} else if (runnable.fException instanceof CoreException) {
							throw (CoreException) runnable.fException;
						}
					}
				}

				buffer.commit(pm, false);
				if (!setContentStampSuccess[0]) {
					fFile.revertModificationStamp(fFileStamp);
				}

				return new CleanUpSaveUndo(getName(), fFile, undoEditCollector.toArray(new UndoEdit[undoEditCollector.size()]), oldDocValue[0], oldFileValue);
			} catch (BadLocationException e) {
				throw wrapBadLocationException(e);
			} finally {
				if (buffer != null)
					manager.disconnect(fFile.getFullPath(), LocationKind.IFILE, new SubProgressMonitor(pm, 1));
			}
		}

		private void performEdit(IDocument document, long oldFileValue, LinkedList<UndoEdit> editCollector, long[] oldDocValue, boolean[] setContentStampSuccess) throws MalformedTreeException, BadLocationException, CoreException {
			if (document instanceof IDocumentExtension4) {
				oldDocValue[0]= ((IDocumentExtension4)document).getModificationStamp();
			} else {
				oldDocValue[0]= oldFileValue;
			}

			// perform the changes
			for (int index= 0; index < fUndos.length; index++) {
				UndoEdit edit= fUndos[index];
				UndoEdit redo= edit.apply(document, TextEdit.CREATE_UNDO);
				editCollector.addFirst(redo);
			}

			if (document instanceof IDocumentExtension4 && fDocumentStamp != IDocumentExtension4.UNKNOWN_MODIFICATION_STAMP) {
				try {
					((IDocumentExtension4)document).replace(0, 0, "", fDocumentStamp); //$NON-NLS-1$
					setContentStampSuccess[0]= true;
				} catch (BadLocationException e) {
					throw wrapBadLocationException(e);
				}
			}
		}
	}

	private static final class SlowCleanUpWarningDialog extends OptionalMessageDialog {

		private static final String ID= "SaveActions.slowWarningDialog"; //$NON-NLS-1$

		private final String fCleanUpNames;

		protected SlowCleanUpWarningDialog(Shell parent, String title, String cleanUpNames) {
			super(ID, parent, title, null, null, MessageDialog.WARNING, new String[] { IDialogConstants.OK_LABEL, IDialogConstants.CANCEL_LABEL }, 0);
			fCleanUpNames= cleanUpNames;
		}

		/* (non-Javadoc)
		 * @see org.eclipse.jface.dialogs.IconAndMessageDialog#createMessageArea(org.eclipse.swt.widgets.Composite)
		 */
		@Override
		protected Control createMessageArea(Composite parent) {
			initializeDialogUnits(parent);

			Composite messageComposite= new Composite(parent, SWT.NONE);
			messageComposite.setFont(parent.getFont());
			GridLayout layout= new GridLayout();
			layout.numColumns= 1;
			layout.marginHeight= 0;
			layout.marginWidth= 0;
			layout.verticalSpacing= convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING);
			layout.horizontalSpacing= convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_SPACING);
			messageComposite.setLayout(layout);
			messageComposite.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

			Label explain= new Label(messageComposite, SWT.WRAP);
			explain.setLayoutData(new GridData(SWT.BEGINNING, SWT.CENTER, false, false));
			explain.setText(FixMessages.CleanUpPostSaveListener_SlowCleanUpWarningDialog_explain);

			final BulletListBlock cleanUpListBlock= new BulletListBlock(messageComposite, SWT.NONE);
			GridData gridData= new GridData(SWT.FILL, SWT.FILL, true, true);
			cleanUpListBlock.setLayoutData(gridData);
			cleanUpListBlock.setText(fCleanUpNames);

			TextLayout textLayout= new TextLayout(messageComposite.getDisplay());
			textLayout.setText(fCleanUpNames);
			int lineCount= textLayout.getLineCount();
			if (lineCount < 5)
				gridData.heightHint= textLayout.getLineBounds(0).height * 6;
			textLayout.dispose();

			Link link= new Link(messageComposite, SWT.NONE);
			link.setLayoutData(new GridData(SWT.BEGINNING, SWT.CENTER, false, false));
			link.setText(FixMessages.CleanUpPostSaveListener_SlowCleanUpDialog_link);

			link.addSelectionListener(new SelectionAdapter() {
				/*
				 * @see org.eclipse.swt.events.SelectionAdapter#widgetSelected(org.eclipse.swt.events.SelectionEvent)
				 */
				@Override
				public void widgetSelected(SelectionEvent e) {
					PreferencesUtil.createPreferenceDialogOn(getShell(), SaveParticipantPreferencePage.PREFERENCE_PAGE_ID, null, null).open();
				}
			});

			return messageComposite;
		}
	}

	public static final String POSTSAVELISTENER_ID= "org.eclipse.jdt.ui.postsavelistener.cleanup"; //$NON-NLS-1$
	private static final String WARNING_VALUE= "warning"; //$NON-NLS-1$
	private static final String ERROR_VALUE= "error"; //$NON-NLS-1$
	private static final String CHANGED_REGION_POSITION_CATEGORY= "changed_region_position_category"; //$NON-NLS-1$
	private static boolean FIRST_CALL= false;
	private static boolean FIRST_CALL_DONE= false;

	/**
	 * {@inheritDoc}
	 */
	public boolean needsChangedRegions(ICompilationUnit unit) throws CoreException {
		ICleanUp[] cleanUps= getCleanUps(unit.getJavaProject().getProject());
		return requiresChangedRegions(cleanUps);
	}

	/**
	 * {@inheritDoc}
	 */
	public void saved(ICompilationUnit unit, IRegion[] changedRegions, IProgressMonitor monitor) throws CoreException {
		if (monitor == null)
			monitor= new NullProgressMonitor();

		monitor.beginTask(getName(), IProgressMonitor.UNKNOWN);

		try {
			if (!ActionUtil.isOnBuildPath(unit))
				return;

			ICleanUp[] cleanUps= getCleanUps(unit.getJavaProject().getProject());

			long oldFileValue= unit.getResource().getModificationStamp();
			long oldDocValue= getDocumentStamp((IFile)unit.getResource(), new SubProgressMonitor(monitor, 2));

			CompositeChange result= new CompositeChange(FixMessages.CleanUpPostSaveListener_SaveAction_ChangeName);
			LinkedList<UndoEdit> undoEdits= new LinkedList<UndoEdit>();

			if (FIRST_CALL && !FIRST_CALL_DONE) {
				FIRST_CALL= false;
				FIRST_CALL_DONE= true;
			} else {
				FIRST_CALL= true;
			}
			HashSet<ICleanUp> slowCleanUps;
			if (FIRST_CALL_DONE) {
				slowCleanUps= new HashSet<ICleanUp>();
			} else {
				slowCleanUps= null;
			}
			IUndoManager manager= RefactoringCore.getUndoManager();

			boolean success= false;
			try {
    			manager.aboutToPerformChange(result);

    			do {
    				RefactoringStatus preCondition= new RefactoringStatus();
    				for (int i= 0; i < cleanUps.length; i++) {
    					RefactoringStatus conditions= cleanUps[i].checkPreConditions(unit.getJavaProject(), new ICompilationUnit[] {unit}, new SubProgressMonitor(monitor, 5));
    					preCondition.merge(conditions);
    				}
    				if (showStatus(preCondition) != Window.OK)
    					return;

    				Map<String, String> options= new HashMap<String, String>();
    				for (int i= 0; i < cleanUps.length; i++) {
    					Map<String, String> map= cleanUps[i].getRequirements().getCompilerOptions();
    					if (map != null) {
    						options.putAll(map);
    					}
    				}

    				CompilationUnit ast= null;
    				if (requiresAST(cleanUps)) {
    					ast= createAst(unit, options, new SubProgressMonitor(monitor, 10));
    				}

    				CleanUpContext context;
    				if (changedRegions == null) {
    					context= new CleanUpContext(unit, ast);
    				} else {
    					context= new MultiLineCleanUpContext(unit, ast, changedRegions);
    				}

    				ArrayList<ICleanUp> undoneCleanUps= new ArrayList<ICleanUp>();
					CleanUpChange change= CleanUpRefactoring.calculateChange(context, cleanUps, undoneCleanUps, slowCleanUps);

    				RefactoringStatus postCondition= new RefactoringStatus();
    				for (int i= 0; i < cleanUps.length; i++) {
    					RefactoringStatus conditions= cleanUps[i].checkPostConditions(new SubProgressMonitor(monitor, 1));
    					postCondition.merge(conditions);
    				}
    				if (showStatus(postCondition) != Window.OK)
    					return;

    				cleanUps= undoneCleanUps.toArray(new ICleanUp[undoneCleanUps.size()]);
    				if (change != null) {
    					result.add(change);

    					change.setSaveMode(TextFileChange.LEAVE_DIRTY);
    					change.initializeValidationData(new NullProgressMonitor());

    					PerformChangeOperation performChangeOperation= RefactoringUI.createUIAwareChangeOperation(change);
    					performChangeOperation.setSchedulingRule(unit.getSchedulingRule());

    					if (changedRegions != null && changedRegions.length > 0 && requiresChangedRegions(cleanUps)) {
							changedRegions= performWithChangedRegionUpdate(performChangeOperation, changedRegions, unit, new SubProgressMonitor(monitor, 5));
						} else {
							performChangeOperation.run(new SubProgressMonitor(monitor, 5));
						}

    					performChangeOperation.getUndoChange();
    					undoEdits.addFirst(change.getUndoEdit());
    				}
    			} while (cleanUps.length > 0);
    			success= true;
			} finally {
				manager.changePerformed(result, success);
			}

			if (undoEdits.size() > 0) {
    			UndoEdit[] undoEditArray= undoEdits.toArray(new UndoEdit[undoEdits.size()]);
    			CleanUpSaveUndo undo= new CleanUpSaveUndo(result.getName(), (IFile)unit.getResource(), undoEditArray, oldDocValue, oldFileValue);
    			undo.initializeValidationData(new NullProgressMonitor());
    			manager.addUndo(result.getName(), undo);
			}

			if (slowCleanUps != null && slowCleanUps.size() > 0)
				showSlowCleanUpsWarning(slowCleanUps);
		} finally {
			monitor.done();
		}
	}

	private static ICleanUp[] getCleanUps(IProject project) throws CoreException {
		ICleanUp[] cleanUps;
		Map<String, String> settings= CleanUpPreferenceUtil.loadSaveParticipantOptions(new ProjectScope(project));
		if (settings == null) {
			IEclipsePreferences contextNode= InstanceScope.INSTANCE.getNode(JavaUI.ID_PLUGIN);
			String id= contextNode.get(CleanUpConstants.CLEANUP_ON_SAVE_PROFILE, null);
			if (id == null) {
				id= DefaultScope.INSTANCE.getNode(JavaUI.ID_PLUGIN).get(CleanUpConstants.CLEANUP_ON_SAVE_PROFILE, CleanUpConstants.DEFAULT_SAVE_PARTICIPANT_PROFILE);
			}
			throw new CoreException(new Status(IStatus.ERROR, JavaUI.ID_PLUGIN, Messages.format(FixMessages.CleanUpPostSaveListener_unknown_profile_error_message, id)));
		}

		if (CleanUpOptions.TRUE.equals(settings.get(CleanUpConstants.CLEANUP_ON_SAVE_ADDITIONAL_OPTIONS))) {
			cleanUps= getCleanUps(settings, null);
		} else {
			HashMap<String, String> filteredSettins= new HashMap<String, String>();
			filteredSettins.put(CleanUpConstants.FORMAT_SOURCE_CODE, settings.get(CleanUpConstants.FORMAT_SOURCE_CODE));
			filteredSettins.put(CleanUpConstants.FORMAT_SOURCE_CODE_CHANGES_ONLY, settings.get(CleanUpConstants.FORMAT_SOURCE_CODE_CHANGES_ONLY));
			filteredSettins.put(CleanUpConstants.ORGANIZE_IMPORTS, settings.get(CleanUpConstants.ORGANIZE_IMPORTS));
			Set<String> ids= new HashSet<String>(2);
			ids.add("org.eclipse.jdt.ui.cleanup.format"); //$NON-NLS-1$
			ids.add("org.eclipse.jdt.ui.cleanup.imports"); //$NON-NLS-1$
			cleanUps= getCleanUps(filteredSettins, ids);
		}

		return cleanUps;
	}

	private static ICleanUp[] getCleanUps(Map<String, String> settings, Set<String> ids) {
		ICleanUp[] result= JavaPlugin.getDefault().getCleanUpRegistry().createCleanUps(ids);

		for (int i= 0; i < result.length; i++) {
			result[i].setOptions(new MapCleanUpOptions(settings));
		}

		return result;
	}


	private int showStatus(RefactoringStatus status) {
		if (!status.hasError())
			return Window.OK;

		Shell shell= PlatformUI.getWorkbench().getActiveWorkbenchWindow().getShell();

		Dialog dialog= RefactoringUI.createRefactoringStatusDialog(status, shell, "", false); //$NON-NLS-1$
		return dialog.open();
    }

	private long getDocumentStamp(IFile file, IProgressMonitor monitor) throws CoreException {
	    final ITextFileBufferManager manager= FileBuffers.getTextFileBufferManager();
	    final IPath path= file.getFullPath();

	    monitor.beginTask("", 2); //$NON-NLS-1$

	    ITextFileBuffer buffer= null;
	    try {
	    	manager.connect(path, LocationKind.IFILE, new SubProgressMonitor(monitor, 1));
		    buffer= manager.getTextFileBuffer(path, LocationKind.IFILE);
    	    IDocument document= buffer.getDocument();

    	    if (document instanceof IDocumentExtension4) {
    			return ((IDocumentExtension4)document).getModificationStamp();
    		} else {
    			return file.getModificationStamp();
    		}
	    } finally {
	    	if (buffer != null)
	    		manager.disconnect(path, LocationKind.IFILE, new SubProgressMonitor(monitor, 1));
	    	monitor.done();
	    }
    }

	private IRegion[] performWithChangedRegionUpdate(PerformChangeOperation performChangeOperation, IRegion[] changedRegions, ICompilationUnit unit, IProgressMonitor monitor) throws CoreException {
		final ITextFileBufferManager manager= FileBuffers.getTextFileBufferManager();
		final IPath path= unit.getResource().getFullPath();

		monitor.beginTask("", 7); //$NON-NLS-1$

		ITextFileBuffer buffer= null;
		try {
			manager.connect(path, LocationKind.IFILE, new SubProgressMonitor(monitor, 1));
			buffer= manager.getTextFileBuffer(path, LocationKind.IFILE);
			IDocument document= buffer.getDocument();

			document.addPositionCategory(CHANGED_REGION_POSITION_CATEGORY);
			DefaultPositionUpdater updater= new DefaultPositionUpdater(CHANGED_REGION_POSITION_CATEGORY);
			try {
				document.addPositionUpdater(updater);

				Position[] positions= new Position[changedRegions.length];
				for (int i= 0; i < changedRegions.length; i++) {
					try {
						Position position= new Position(changedRegions[i].getOffset(), changedRegions[i].getLength());
						document.addPosition(CHANGED_REGION_POSITION_CATEGORY, position);

						positions[i]= position;
					} catch (BadLocationException e) {
						throw wrapBadLocationException(e);
					} catch (BadPositionCategoryException e) {
						throw wrapBadPositionCategoryException(e);
					}
				}

				performChangeOperation.run(new SubProgressMonitor(monitor, 5));

				ArrayList<Region> result= new ArrayList<Region>();
				for (int i= 0; i < positions.length; i++) {
					Position position= positions[i];
					if (!position.isDeleted())
						result.add(new Region(position.getOffset(), position.getLength()));
				}

				return result.toArray(new IRegion[result.size()]);
			} finally {
				document.removePositionUpdater(updater);
				try {
					document.removePositionCategory(CHANGED_REGION_POSITION_CATEGORY);
				} catch (BadPositionCategoryException e) {
					throw wrapBadPositionCategoryException(e);
				}
			}
		} finally {
			if (buffer != null)
				manager.disconnect(path, LocationKind.IFILE, new SubProgressMonitor(monitor, 1));
			monitor.done();
		}
	}

	private boolean requiresAST(ICleanUp[] cleanUps) {
		for (int i= 0; i < cleanUps.length; i++) {
	        if (cleanUps[i].getRequirements().requiresAST())
	        	return true;
        }

	    return false;
    }

	private boolean requiresChangedRegions(ICleanUp[] cleanUps) {
		for (int i= 0; i < cleanUps.length; i++) {
			CleanUpRequirements requirements= cleanUps[i].getRequirements();
			if (requirements.requiresChangedRegions())
				return true;
		}

		return false;
	}

	private CompilationUnit createAst(ICompilationUnit unit, Map<String, String> cleanUpOptions, IProgressMonitor monitor) {
		IJavaProject project= unit.getJavaProject();
		if (compatibleOptions(project, cleanUpOptions)) {
			CompilationUnit ast= SharedASTProvider.getAST(unit, SharedASTProvider.WAIT_NO, monitor);
			if (ast != null)
				return ast;
		}

		ASTParser parser= CleanUpRefactoring.createCleanUpASTParser();
		parser.setSource(unit);

		Map<String, String> compilerOptions= RefactoringASTParser.getCompilerOptions(unit.getJavaProject());
		compilerOptions.putAll(cleanUpOptions);
		parser.setCompilerOptions(compilerOptions);

		return (CompilationUnit)parser.createAST(monitor);
	}

	private boolean compatibleOptions(IJavaProject project, Map<String, String> cleanUpOptions) {
		if (cleanUpOptions.size() == 0)
			return true;

		Map<String, String> projectOptions= project.getOptions(true);

		for (Iterator<String> iterator= cleanUpOptions.keySet().iterator(); iterator.hasNext();) {
	        String key= iterator.next();
	        String projectOption= projectOptions.get(key);
			String cleanUpOption= cleanUpOptions.get(key);
			if (!strongerEquals(projectOption, cleanUpOption))
				return false;
        }

	    return true;
    }

	private boolean strongerEquals(String projectOption, String cleanUpOption) {
		if (projectOption == null)
			return false;

		if (ERROR_VALUE.equals(cleanUpOption)) {
			return ERROR_VALUE.equals(projectOption);
		} else if (WARNING_VALUE.equals(cleanUpOption)) {
			return ERROR_VALUE.equals(projectOption) || WARNING_VALUE.equals(projectOption);
		}

	    return false;
    }

	/**
	 * {@inheritDoc}
	 */
	public String getName() {
		return FixMessages.CleanUpPostSaveListener_name;
	}

	/**
	 * {@inheritDoc}
	 */
	public String getId() {
		return POSTSAVELISTENER_ID;
	}

	private static CoreException wrapBadLocationException(BadLocationException e) {
		String message= e.getMessage();
		if (message == null)
			message= "BadLocationException"; //$NON-NLS-1$
		return new CoreException(new Status(IStatus.ERROR, JavaUI.ID_PLUGIN, IRefactoringCoreStatusCodes.BAD_LOCATION, message, e));
	}

	private CoreException wrapBadPositionCategoryException(BadPositionCategoryException e) {
		String message= e.getMessage();
		if (message == null)
			message= "BadPositionCategoryException"; //$NON-NLS-1$
		return new CoreException(new Status(IStatus.ERROR, JavaUI.ID_PLUGIN, 0, message, e));
	}

	private void showSlowCleanUpsWarning(HashSet<ICleanUp> slowCleanUps) {

		final StringBuffer cleanUpNames= new StringBuffer();
		for (Iterator<ICleanUp> iterator= slowCleanUps.iterator(); iterator.hasNext();) {
			ICleanUp cleanUp= iterator.next();
			String[] descriptions= cleanUp.getStepDescriptions();
			if (descriptions != null) {
				for (int i= 0; i < descriptions.length; i++) {
					if (cleanUpNames.length() > 0)
						cleanUpNames.append('\n');

					cleanUpNames.append(descriptions[i]);
				}
			}
		}

		if (Display.getCurrent() != null) {
			showSlowCleanUpDialog(cleanUpNames);
		} else {
			Display.getDefault().asyncExec(new Runnable() {
				public void run() {
					showSlowCleanUpDialog(cleanUpNames);
				}
			});
		}
	}

	private void showSlowCleanUpDialog(final StringBuffer cleanUpNames) {
		if (OptionalMessageDialog.isDialogEnabled(SlowCleanUpWarningDialog.ID)) {
			Shell shell= PlatformUI.getWorkbench().getActiveWorkbenchWindow().getShell();
			new SlowCleanUpWarningDialog(shell, FixMessages.CleanUpPostSaveListener_SlowCleanUpDialog_title, cleanUpNames.toString()).open();
		}
	}

}
