/*******************************************************************************
 * 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.refactoring.rename;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;

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

import org.eclipse.ltk.core.refactoring.Change;
import org.eclipse.ltk.core.refactoring.IResourceMapper;
import org.eclipse.ltk.core.refactoring.RefactoringChangeDescriptor;
import org.eclipse.ltk.core.refactoring.RefactoringCore;
import org.eclipse.ltk.core.refactoring.RefactoringDescriptor;
import org.eclipse.ltk.core.refactoring.RefactoringStatus;
import org.eclipse.ltk.core.refactoring.participants.CheckConditionsContext;
import org.eclipse.ltk.core.refactoring.participants.RenameArguments;
import org.eclipse.ltk.core.refactoring.resource.RenameResourceChange;
import org.eclipse.ltk.core.refactoring.resource.RenameResourceDescriptor;

import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IPackageFragment;
import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.refactoring.IJavaElementMapper;
import org.eclipse.jdt.core.refactoring.IJavaRefactorings;
import org.eclipse.jdt.core.refactoring.RenameTypeArguments;
import org.eclipse.jdt.core.refactoring.descriptors.RenameJavaElementDescriptor;

import org.eclipse.jdt.internal.core.refactoring.descriptors.RefactoringSignatureDescriptorFactory;
import org.eclipse.jdt.internal.corext.refactoring.Checks;
import org.eclipse.jdt.internal.corext.refactoring.JDTRefactoringDescriptorComment;
import org.eclipse.jdt.internal.corext.refactoring.JavaRefactoringArguments;
import org.eclipse.jdt.internal.corext.refactoring.JavaRefactoringDescriptorUtil;
import org.eclipse.jdt.internal.corext.refactoring.RefactoringAvailabilityTester;
import org.eclipse.jdt.internal.corext.refactoring.RefactoringCoreMessages;
import org.eclipse.jdt.internal.corext.refactoring.changes.DynamicValidationRefactoringChange;
import org.eclipse.jdt.internal.corext.refactoring.changes.DynamicValidationStateChange;
import org.eclipse.jdt.internal.corext.refactoring.changes.RenameCompilationUnitChange;
import org.eclipse.jdt.internal.corext.refactoring.participants.JavaProcessors;
import org.eclipse.jdt.internal.corext.refactoring.tagging.IQualifiedNameUpdating;
import org.eclipse.jdt.internal.corext.refactoring.tagging.IReferenceUpdating;
import org.eclipse.jdt.internal.corext.refactoring.tagging.ISimilarDeclarationUpdating;
import org.eclipse.jdt.internal.corext.refactoring.tagging.ITextUpdating;
import org.eclipse.jdt.internal.corext.refactoring.util.ResourceUtil;
import org.eclipse.jdt.internal.corext.util.JavaConventionsUtil;
import org.eclipse.jdt.internal.corext.util.Messages;

import org.eclipse.jdt.ui.JavaElementLabels;
import org.eclipse.jdt.ui.refactoring.IRefactoringProcessorIds;
import org.eclipse.jdt.ui.refactoring.RefactoringSaveHelper;

import org.eclipse.jdt.internal.ui.JavaPlugin;
import org.eclipse.jdt.internal.ui.viewsupport.BasicElementLabels;

public final class RenameCompilationUnitProcessor extends JavaRenameProcessor implements IReferenceUpdating, ITextUpdating, IQualifiedNameUpdating, ISimilarDeclarationUpdating, IResourceMapper, IJavaElementMapper {

	private RenameTypeProcessor fRenameTypeProcessor= null;
	private boolean fWillRenameType= false;
	private ICompilationUnit fCu;

	/**
	 * Creates a new rename compilation unit processor.
	 * @param unit the compilation unit, or <code>null</code> if invoked by scripting
	 * @throws CoreException if the cu is broken
	 */
	public RenameCompilationUnitProcessor(ICompilationUnit unit) throws CoreException {
		fCu= unit;
		if (fCu != null) {
			computeRenameTypeRefactoring();
			setNewElementName(fCu.getElementName());
		}
	}

	public RenameCompilationUnitProcessor(JavaRefactoringArguments arguments, RefactoringStatus status) {
		RefactoringStatus initializeStatus= initialize(arguments);
		status.merge(initializeStatus);
	}

	@Override
	public String getIdentifier() {
		return IRefactoringProcessorIds.RENAME_COMPILATION_UNIT_PROCESSOR;
	}

	@Override
	public boolean isApplicable() {
		return RefactoringAvailabilityTester.isRenameAvailable(fCu);
	}

	@Override
	public String getProcessorName() {
		return RefactoringCoreMessages.RenameCompilationUnitRefactoring_name;
	}

	@Override
	protected String[] getAffectedProjectNatures() throws CoreException {
		return JavaProcessors.computeAffectedNatures(fCu);
	}

	@Override
	public Object[] getElements() {
		return new Object[] {fCu};
	}

	@Override
	protected RenameModifications computeRenameModifications() {
		RenameModifications result= new RenameModifications();
		result.rename(fCu, new RenameArguments(getNewElementName(), getUpdateReferences()));
		if (fRenameTypeProcessor != null) {
			String newTypeName= removeFileNameExtension(getNewElementName());
			RenameTypeArguments arguments= new RenameTypeArguments(newTypeName, getUpdateReferences(), getUpdateSimilarDeclarations(), getSimilarElements());
			result.rename(fRenameTypeProcessor.getType(), arguments, getUpdateSimilarDeclarations()
				? new RenameTypeProcessor.ParticipantDescriptorFilter()
				: null);
		}
		return result;
	}

	@Override
	protected IFile[] getChangedFiles() throws CoreException {
		if (!fWillRenameType) {
			IFile file= ResourceUtil.getFile(fCu);
			if (file != null)
				return new IFile[] {file};
		}
		return new IFile[0];
	}

	@Override
	public int getSaveMode() {
		return RefactoringSaveHelper.SAVE_REFACTORING;
	}

	//---- IRenameProcessor -------------------------------------

	public String getCurrentElementName() {
		return getSimpleCUName();
	}

	public String getCurrentElementQualifier() {
		IPackageFragment pack= (IPackageFragment) fCu.getParent();
		return pack.getElementName();
	}

	public RefactoringStatus checkNewElementName(String newName) throws CoreException {
		Assert.isNotNull(newName, "new name"); //$NON-NLS-1$
		String typeName= removeFileNameExtension(newName);
		RefactoringStatus result= Checks.checkCompilationUnitName(newName, fCu);
		if (fWillRenameType)
			result.merge(fRenameTypeProcessor.checkNewElementName(typeName));
		if (Checks.isAlreadyNamed(fCu, newName))
			result.addFatalError(RefactoringCoreMessages.RenameCompilationUnitRefactoring_same_name);
		return result;
	}

	@Override
	public void setNewElementName(String newName) {
		super.setNewElementName(newName);
		if (fWillRenameType)
			fRenameTypeProcessor.setNewElementName(removeFileNameExtension(newName));
	}

	public Object getNewElement() {
		IPackageFragment pack= (IPackageFragment) fCu.getParent();
		if (JavaConventionsUtil.validateCompilationUnitName(getNewElementName(), pack).getSeverity() == IStatus.ERROR)
			return null;
		return pack.getCompilationUnit(getNewElementName());
	}

	//---- ITextUpdating ---------------------------------------------

	public boolean canEnableTextUpdating() {
		if (fRenameTypeProcessor == null)
			return false;
		return fRenameTypeProcessor.canEnableTextUpdating();
	}

	public boolean getUpdateTextualMatches() {
		if (fRenameTypeProcessor == null)
			return false;
		return fRenameTypeProcessor.getUpdateTextualMatches();
	}

	public void setUpdateTextualMatches(boolean update) {
		if (fRenameTypeProcessor != null)
			fRenameTypeProcessor.setUpdateTextualMatches(update);
	}

	//---- IReferenceUpdating -----------------------------------

	public void setUpdateReferences(boolean update) {
		if (fRenameTypeProcessor != null)
			fRenameTypeProcessor.setUpdateReferences(update);
	}

	public boolean getUpdateReferences(){
		if (fRenameTypeProcessor == null)
			return false;
		return fRenameTypeProcessor.getUpdateReferences();
	}

	//---- IQualifiedNameUpdating -------------------------------

	public boolean canEnableQualifiedNameUpdating() {
		if (fRenameTypeProcessor == null)
			return false;
		return fRenameTypeProcessor.canEnableQualifiedNameUpdating();
	}

	public boolean getUpdateQualifiedNames() {
		if (fRenameTypeProcessor == null)
			return false;
		return fRenameTypeProcessor.getUpdateQualifiedNames();
	}

	public void setUpdateQualifiedNames(boolean update) {
		if (fRenameTypeProcessor == null)
			return;
		fRenameTypeProcessor.setUpdateQualifiedNames(update);
	}

	public String getFilePatterns() {
		if (fRenameTypeProcessor == null)
			return null;
		return fRenameTypeProcessor.getFilePatterns();
	}

	public void setFilePatterns(String patterns) {
		if (fRenameTypeProcessor == null)
			return;
		fRenameTypeProcessor.setFilePatterns(patterns);
	}

	// ---- ISimilarDeclarationUpdating ------------------------------

	public boolean canEnableSimilarDeclarationUpdating() {
		if (fRenameTypeProcessor == null)
			return false;
		else
			return fRenameTypeProcessor.canEnableSimilarDeclarationUpdating();
	}

	public void setUpdateSimilarDeclarations(boolean update) {
		if (fRenameTypeProcessor == null)
			return;
		fRenameTypeProcessor.setUpdateSimilarDeclarations(update);
	}

	public boolean getUpdateSimilarDeclarations() {
		if (fRenameTypeProcessor == null)
			return false;
		return fRenameTypeProcessor.getUpdateSimilarDeclarations();
	}

	public int getMatchStrategy() {
		if (fRenameTypeProcessor == null)
			return RenamingNameSuggestor.STRATEGY_EXACT; // method should not be called in this case anyway ...
		return fRenameTypeProcessor.getMatchStrategy();
	}

	public void setMatchStrategy(int selectedStrategy) {
		if (fRenameTypeProcessor == null)
			return;
		fRenameTypeProcessor.setMatchStrategy(selectedStrategy);
	}

	public IJavaElement[] getSimilarElements() {
		if (fRenameTypeProcessor == null)
			return null;
		return fRenameTypeProcessor.getSimilarElements();
	}

	public IResource getRefactoredResource(IResource element) {
		if (fRenameTypeProcessor == null)
			return element;
		return fRenameTypeProcessor.getRefactoredResource(element);
	}

	public IJavaElement getRefactoredJavaElement(IJavaElement element) {
		if (fRenameTypeProcessor == null)
			return element;
		return fRenameTypeProcessor.getRefactoredJavaElement(element);
	}

	// --- preconditions ----------------------------------

	@Override
	public RefactoringStatus checkInitialConditions(IProgressMonitor pm) throws CoreException {
		if (fRenameTypeProcessor != null && ! fCu.isStructureKnown()){
			fRenameTypeProcessor= null;
			fWillRenameType= false;
			return new RefactoringStatus();
		}

		//for a test case what it's needed, see bug 24248
		//(the type might be gone from the editor by now)
		if (fWillRenameType && fRenameTypeProcessor != null && ! fRenameTypeProcessor.getType().exists()){
			fRenameTypeProcessor= null;
			fWillRenameType= false;
			return new RefactoringStatus();
		}

		// we purposely do not check activation of the renameTypeRefactoring here.
		return new RefactoringStatus();
	}

	@Override
	protected RefactoringStatus doCheckFinalConditions(IProgressMonitor pm, CheckConditionsContext context) throws CoreException {
		try{
			if (fWillRenameType && (!fCu.isStructureKnown())){
				RefactoringStatus result1= new RefactoringStatus();

				RefactoringStatus result2= new RefactoringStatus();
				result2.merge(Checks.checkCompilationUnitNewName(fCu, getNewElementName()));
				if (result2.hasFatalError())
					result1.addError(Messages.format(RefactoringCoreMessages.RenameCompilationUnitRefactoring_not_parsed_1, BasicElementLabels.getFileName(fCu)));
				else
					result1.addError(Messages.format(RefactoringCoreMessages.RenameCompilationUnitRefactoring_not_parsed, BasicElementLabels.getFileName(fCu)));
				result1.merge(result2);
			}

			if (fWillRenameType) {
				return fRenameTypeProcessor.checkFinalConditions(pm, context);
			} else {
				return Checks.checkCompilationUnitNewName(fCu, getNewElementName());
			}
		} finally{
			pm.done();
		}
	}

	private void computeRenameTypeRefactoring() throws CoreException{
		if (getSimpleCUName().indexOf(".") != -1) { //$NON-NLS-1$
			fRenameTypeProcessor= null;
			fWillRenameType= false;
			return;
		}
		IType type= getTypeWithTheSameName();
		if (type != null) {
			fRenameTypeProcessor= new RenameTypeProcessor(type);
		} else {
			fRenameTypeProcessor= null;
		}
		fWillRenameType= fRenameTypeProcessor != null && fCu.isStructureKnown();
	}

	private IType getTypeWithTheSameName() {
		try {
			IType[] topLevelTypes= fCu.getTypes();
			String name= getSimpleCUName();
			for (int i = 0; i < topLevelTypes.length; i++) {
				if (name.equals(topLevelTypes[i].getElementName()))
					return topLevelTypes[i];
			}
			return null;
		} catch (CoreException e) {
			return null;
		}
	}

	private String getSimpleCUName() {
		return removeFileNameExtension(fCu.getElementName());
	}

	/**
	 * Removes the extension (whatever comes after the last '.') from the given file name.
	 * 
	 * @param fileName the file name
	 * @return main type name
	 */
	private static String removeFileNameExtension(String fileName) {
		if (fileName.lastIndexOf(".") == -1) //$NON-NLS-1$
			return fileName;
		return fileName.substring(0, fileName.lastIndexOf(".")); //$NON-NLS-1$
	}

	@Override
	public Change createChange(IProgressMonitor pm) throws CoreException {
		// renaming the file is taken care of in renameTypeRefactoring
		if (fWillRenameType)
			return fRenameTypeProcessor.createChange(pm);
		fRenameTypeProcessor= null;
		final String newName= getNewElementName();
		final IResource resource= fCu.getResource();
		if (resource != null && resource.isLinked()) {
			final IProject project= resource.getProject();
			final String name= project.getName();
			final String description= Messages.format(RefactoringCoreMessages.RenameCompilationUnitChange_descriptor_description_short, BasicElementLabels.getResourceName(resource.getName()));
			final String header= Messages.format(RefactoringCoreMessages.RenameCompilationUnitChange_descriptor_description, new String[] { BasicElementLabels.getPathLabel(resource.getFullPath(), false), BasicElementLabels.getResourceName(resource.getName())});
			final String comment= new JDTRefactoringDescriptorComment(name, this, header).asString();
			final int flags= RefactoringDescriptor.STRUCTURAL_CHANGE;

			final RenameResourceDescriptor descriptor= (RenameResourceDescriptor) RefactoringCore.getRefactoringContribution(RenameResourceDescriptor.ID).createDescriptor();
			descriptor.setProject(name);
			descriptor.setDescription(description);
			descriptor.setComment(comment);
			descriptor.setFlags(flags);
			descriptor.setResourcePath(resource.getFullPath());
			descriptor.setNewName(newName);

			RenameResourceChange resourceChange= new RenameResourceChange(resource.getFullPath(), newName);
			resourceChange.setDescriptor(new RefactoringChangeDescriptor(descriptor));
			return new DynamicValidationStateChange(resourceChange);
		}

		String label= JavaElementLabels.getTextLabel(fCu, JavaElementLabels.ALL_FULLY_QUALIFIED);

		final String name= fCu.getJavaProject().getElementName();
		final String description= Messages.format(RefactoringCoreMessages.RenameCompilationUnitChange_descriptor_description_short, BasicElementLabels.getFileName(fCu));
		final String header= Messages.format(RefactoringCoreMessages.RenameCompilationUnitChange_descriptor_description, new String[] { label, BasicElementLabels.getResourceName(newName)});
		final String comment= new JDTRefactoringDescriptorComment(name, this, header).asString();
		final int flags= RefactoringDescriptor.STRUCTURAL_CHANGE;
		final RenameJavaElementDescriptor descriptor= RefactoringSignatureDescriptorFactory.createRenameJavaElementDescriptor(IJavaRefactorings.RENAME_COMPILATION_UNIT);
		descriptor.setProject(name);
		descriptor.setDescription(description);
		descriptor.setComment(comment);
		descriptor.setFlags(flags);
		descriptor.setJavaElement(fCu);
		descriptor.setNewName(newName);
		return new DynamicValidationRefactoringChange(descriptor, RefactoringCoreMessages.RenameCompilationUnitRefactoring_name, new Change[] { new RenameCompilationUnitChange(fCu, newName)});
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public Change postCreateChange(Change[] participantChanges, IProgressMonitor pm) throws CoreException {
		if (fWillRenameType)
			return fRenameTypeProcessor.postCreateChange(participantChanges, pm);
		return super.postCreateChange(participantChanges, pm);
	}

	private RefactoringStatus initialize(JavaRefactoringArguments extended) {
		final String handle= extended.getAttribute(JavaRefactoringDescriptorUtil.ATTRIBUTE_INPUT);
		if (handle == null) {
			return RefactoringStatus.createFatalErrorStatus(Messages.format(RefactoringCoreMessages.InitializableRefactoring_argument_not_exist, JavaRefactoringDescriptorUtil.ATTRIBUTE_INPUT));
		}

		final IJavaElement element= JavaRefactoringDescriptorUtil.handleToElement(extended.getProject(), handle, false);
		if (element == null || !element.exists() || element.getElementType() != IJavaElement.COMPILATION_UNIT)
			return JavaRefactoringDescriptorUtil.createInputFatalStatus(element, getProcessorName(), IJavaRefactorings.RENAME_COMPILATION_UNIT);

		final String name= extended.getAttribute(JavaRefactoringDescriptorUtil.ATTRIBUTE_NAME);
		if (name == null || name.length() == 0)
			return RefactoringStatus.createFatalErrorStatus(Messages.format(RefactoringCoreMessages.InitializableRefactoring_argument_not_exist, JavaRefactoringDescriptorUtil.ATTRIBUTE_NAME));

		fCu= (ICompilationUnit) element;
		try {
			computeRenameTypeRefactoring();
			setNewElementName(name);
		} catch (CoreException exception) {
			JavaPlugin.log(exception);
			return JavaRefactoringDescriptorUtil.createInputFatalStatus(element, getProcessorName(), IJavaRefactorings.RENAME_COMPILATION_UNIT);
		}
		return new RefactoringStatus();
	}

	/**
	 * @return the RenameTypeProcessor or <code>null</code> if no type will be renamed
	 */
	public RenameTypeProcessor getRenameTypeProcessor() {
		return fRenameTypeProcessor;
	}

	public boolean isWillRenameType() {
		return fWillRenameType;
	}
}