/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 * 
 * SPDX-License-Identifier: EPL-2.0
 *
 *******************************************************************************/
package org.eclipse.dltk.internal.corext.refactoring.reorg;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.mapping.IResourceChangeDescriptionFactory;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.dltk.core.IModelElement;
import org.eclipse.dltk.core.IProjectFragment;
import org.eclipse.dltk.core.IScriptFolder;
import org.eclipse.dltk.core.ISourceModule;
import org.eclipse.dltk.core.IType;
import org.eclipse.dltk.internal.corext.refactoring.participants.ResourceModifications;
import org.eclipse.ltk.core.refactoring.RefactoringStatus;
import org.eclipse.ltk.core.refactoring.participants.IParticipantDescriptorFilter;
import org.eclipse.ltk.core.refactoring.participants.MoveArguments;
import org.eclipse.ltk.core.refactoring.participants.ParticipantManager;
import org.eclipse.ltk.core.refactoring.participants.RefactoringArguments;
import org.eclipse.ltk.core.refactoring.participants.RefactoringParticipant;
import org.eclipse.ltk.core.refactoring.participants.RefactoringProcessor;
import org.eclipse.ltk.core.refactoring.participants.SharableParticipants;
import org.eclipse.ltk.core.refactoring.participants.ValidateEditChecker;

public class MoveModifications extends RefactoringModifications {

	private List fMoves;
	private List fMoveArguments;
	private List fParticipantDescriptorFilter;

	public MoveModifications() {
		fMoves = new ArrayList();
		fMoveArguments = new ArrayList();
		fParticipantDescriptorFilter = new ArrayList();
	}

	public void move(IResource resource, MoveArguments args) {
		add(resource, args, null);
	}

	public void move(IProjectFragment sourceFolder, MoveArguments arguments) {
		add(sourceFolder, arguments, null);
		IResource sourceResource = sourceFolder.getResource();
		if (sourceResource != null) {
			getResourceModifications().addMove(sourceResource,
					new MoveArguments(getResourceDestination(arguments),
							arguments.getUpdateReferences()));
			IFile buildpath = getBuildpathFile(sourceResource);
			if (buildpath != null) {
				getResourceModifications().addChanged(buildpath);
			}
			buildpath = getBuildpathFile(getResourceDestination(arguments));
			if (buildpath != null) {
				getResourceModifications().addChanged(buildpath);
			}
		}
	}

	public void move(IScriptFolder pack, MoveArguments args)
			throws CoreException {
		add(pack, args, null);
		if (pack.getResource() == null)
			return;
		IProjectFragment scriptDestination = (IProjectFragment) args
				.getDestination();
		if (scriptDestination.getResource() == null)
			return;
		IScriptFolder newPack = scriptDestination
				.getScriptFolder(pack.getElementName());
		if (!pack.hasSubfolders() && !newPack.exists()) {
			// we can do a simple move
			IContainer resourceDestination = newPack.getResource().getParent();
			createIncludingParents(resourceDestination);
			getResourceModifications().addMove(pack.getResource(),
					new MoveArguments(resourceDestination,
							args.getUpdateReferences()));
		} else {
			IContainer resourceSource = (IContainer) pack.getResource();
			IContainer resourceDestination = (IContainer) newPack.getResource();
			createIncludingParents(resourceDestination);
			MoveArguments arguments = new MoveArguments(resourceDestination,
					args.getUpdateReferences());
			IResource[] resourcesToMove = collectResourcesOfInterest(pack);
			Set allMembers = new HashSet(
					Arrays.asList(resourceSource.members()));
			for (int i = 0; i < resourcesToMove.length; i++) {
				IResource toMove = resourcesToMove[i];
				getResourceModifications().addMove(toMove, arguments);
				allMembers.remove(toMove);
			}
			for (Iterator iter = allMembers.iterator(); iter.hasNext();) {
				IResource element = (IResource) iter.next();
				if (element instanceof IFile) {
					getResourceModifications().addDelete(element);
					iter.remove();
				}
			}
			if (allMembers.isEmpty()) {
				getResourceModifications().addDelete(resourceSource);
			}
		}
	}

	public void move(ISourceModule unit, MoveArguments args)
			throws CoreException {
		add(unit, args, null);
		IType[] types = unit.getTypes();
		for (int tt = 0; tt < types.length; tt++) {
			add(types[tt], args, null);
		}
		IResource resourceDestination = getResourceDestination(args);
		if (resourceDestination != null && unit.getResource() != null) {
			getResourceModifications().addMove(unit.getResource(),
					new MoveArguments(resourceDestination,
							args.getUpdateReferences()));
		}
	}

	@Override
	public void buildDelta(IResourceChangeDescriptionFactory builder) {
		for (int i = 0; i < fMoves.size(); i++) {
			Object element = fMoves.get(i);
			if (element instanceof IResource) {
				ResourceModifications.buildMoveDelta(builder,
						(IResource) element,
						(MoveArguments) fMoveArguments.get(i));
			}
		}
		getResourceModifications().buildDelta(builder);
	}

	@Override
	public void buildValidateEdits(ValidateEditChecker checker) {
		for (Iterator iter = fMoves.iterator(); iter.hasNext();) {
			Object element = iter.next();
			if (element instanceof ISourceModule) {
				ISourceModule unit = (ISourceModule) element;
				IResource resource = unit.getResource();
				if (resource != null && resource.getType() == IResource.FILE) {
					checker.addFile((IFile) resource);
				}
			}
		}
	}

	@Override
	public RefactoringParticipant[] loadParticipants(RefactoringStatus status,
			RefactoringProcessor owner, String[] natures,
			SharableParticipants shared) {
		List<RefactoringParticipant> result = new ArrayList<>();
		for (int i = 0; i < fMoves.size(); i++) {
			result.addAll(Arrays.asList(ParticipantManager.loadMoveParticipants(
					status, owner, fMoves.get(i),
					(MoveArguments) fMoveArguments.get(i),
					(IParticipantDescriptorFilter) fParticipantDescriptorFilter
							.get(i),
					natures, shared)));
		}
		result.addAll(Arrays.asList(getResourceModifications()
				.getParticipants(status, owner, natures, shared)));
		return result.toArray(new RefactoringParticipant[result.size()]);
	}

	private void add(Object element, RefactoringArguments args,
			IParticipantDescriptorFilter filter) {
		Assert.isNotNull(element);
		Assert.isNotNull(args);
		fMoves.add(element);
		fMoveArguments.add(args);
		fParticipantDescriptorFilter.add(filter);
	}

	private IResource getResourceDestination(MoveArguments args) {
		Object genericDestination = args.getDestination();
		IResource resourceDestination = null;
		if (genericDestination instanceof IModelElement) {
			resourceDestination = ((IModelElement) genericDestination)
					.getResource();
		} else if (genericDestination instanceof IResource) {
			resourceDestination = (IResource) genericDestination;
		}
		return resourceDestination;
	}
}