/*******************************************************************************
 * Copyright (c) 2005, 2006 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 * IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.team.internal.ccvs.ui.mappings;

import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.resources.mapping.ResourceMapping;
import org.eclipse.core.runtime.*;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.swt.widgets.Display;
import org.eclipse.team.core.diff.*;
import org.eclipse.team.core.mapping.IMergeContext;
import org.eclipse.team.core.mapping.ISynchronizationContext;
import org.eclipse.team.internal.ccvs.ui.CVSUIMessages;
import org.eclipse.team.internal.ccvs.ui.CVSUIPlugin;
import org.eclipse.ui.IWorkbenchPart;

public class ModelReplaceOperation extends ModelUpdateOperation {
	
	boolean hasPrompted = false;

	public ModelReplaceOperation(IWorkbenchPart part, ResourceMapping[] selectedMappings, boolean consultModels) {
		super(part, selectedMappings, consultModels);
	}
	
	@Override
	protected String getJobName() {
		return CVSUIMessages.ReplaceOperation_taskName;
	}
	
	@Override
	protected boolean isAttemptHeadlessMerge() {
		return true;
	}
	
	@Override
	protected boolean hasChangesOfInterest() {
		IMergeContext context = (IMergeContext)getContext();
		return !context.getDiffTree().isEmpty();
	}
	
	@Override
	protected int getMergeType() {
		return ISynchronizationContext.TWO_WAY;
	}
	
	@Override
	protected IStatus performMerge(IProgressMonitor monitor) throws CoreException {
		if (!hasLocalChanges() || promptForOverwrite()) {
			return super.performMerge(monitor);
		}
		return new Status(IStatus.ERROR, CVSUIPlugin.ID, REQUEST_PREVIEW, "", null); //$NON-NLS-1$
	}

	/*
	 * Mde porotected to be overriden by test cases.
	 */
	protected boolean promptForOverwrite() {
		if (hasPrompted)
			return true;
		final int[] result = new int[] { 1 };
		Display.getDefault().syncExec(() -> {
			MessageDialog dialog = new MessageDialog(getShell(), CVSUIMessages.ModelReplaceOperation_0, null, // accept
					// the
					// default
					// window
					// icon
					CVSUIMessages.ModelReplaceOperation_1, MessageDialog.QUESTION,
					new String[] { CVSUIMessages.ModelReplaceOperation_2, CVSUIMessages.ModelReplaceOperation_3,
							IDialogConstants.CANCEL_LABEL },
					result[0]); // preview is the default

			result[0] = dialog.open();

		});
		if (result[0] == 2)
			throw new OperationCanceledException();
		hasPrompted = true;
		return result[0] == 0;
	}

	private boolean hasLocalChanges() {
		return getContext().getDiffTree().hasMatchingDiffs(ResourcesPlugin.getWorkspace().getRoot().getFullPath(), new FastDiffFilter() {
			@Override
			public boolean select(IDiff node) {
				if (node instanceof IThreeWayDiff) {
					IThreeWayDiff twd = (IThreeWayDiff) node;
					int direction = twd.getDirection();
					if (direction == IThreeWayDiff.OUTGOING || direction == IThreeWayDiff.CONFLICTING) {
						return true;
					}
				} else {
					// Return true for any two-way change
					return true;
				}
				return false;
			}
		});
	}
}