/*
 * Copyright (C) 2017, Google Inc.
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials provided
 *   with the distribution.
 *
 * - Neither the name of the Eclipse Foundation, Inc. nor the
 *   names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior
 *   written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.eclipse.jgit.internal.revwalk;

import org.eclipse.jgit.lib.BitmapIndex.Bitmap;
import org.eclipse.jgit.lib.BitmapIndex.BitmapBuilder;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.revwalk.filter.RevFilter;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevFlag;

A RevFilter that adds the visited commits to bitmap as a side effect. 
 When the walk hits a commit that is part of bitmap's BitmapIndex, that entire bitmap is ORed into bitmap and the commit and its parents are marked as SEEN so that the walk does not have to visit its ancestors. This ensures the walk is very short if there is good bitmap coverage. /**
 * A RevFilter that adds the visited commits to {@code bitmap} as a side
 * effect.
 * <p>
 * When the walk hits a commit that is part of {@code bitmap}'s
 * BitmapIndex, that entire bitmap is ORed into {@code bitmap} and the
 * commit and its parents are marked as SEEN so that the walk does not
 * have to visit its ancestors.  This ensures the walk is very short if
 * there is good bitmap coverage.
 */
public class AddToBitmapFilter extends RevFilter {
	private final BitmapBuilder bitmap;

	
Create a filter that adds visited commits to the given bitmap.
Params:
bitmap – bitmap to write visited commits to/**
	 * Create a filter that adds visited commits to the given bitmap.
	 *
	 * @param bitmap bitmap to write visited commits to
	 */
	public AddToBitmapFilter(BitmapBuilder bitmap) {
		this.bitmap = bitmap;
	}

	
{@inheritDoc} /** {@inheritDoc} */
	@Override
	public final boolean include(RevWalk walker, RevCommit cmit) {
		Bitmap visitedBitmap;

		if (bitmap.contains(cmit)) {
			// already included
		} else if ((visitedBitmap = bitmap.getBitmapIndex()
				.getBitmap(cmit)) != null) {
			bitmap.or(visitedBitmap);
		} else {
			bitmap.addObject(cmit, Constants.OBJ_COMMIT);
			return true;
		}

		for (RevCommit p : cmit.getParents()) {
			p.add(RevFlag.SEEN);
		}
		return false;
	}

	
{@inheritDoc} /** {@inheritDoc} */
	@Override
	public final RevFilter clone() {
		throw new UnsupportedOperationException();
	}

	
{@inheritDoc} /** {@inheritDoc} */
	@Override
	public final boolean requiresCommitBody() {
		return false;
	}
}