tikhomirov@128: /*
tikhomirov@128:  * Copyright (c) 2011 TMate Software Ltd
tikhomirov@128:  *  
tikhomirov@128:  * This program is free software; you can redistribute it and/or modify
tikhomirov@128:  * it under the terms of the GNU General Public License as published by
tikhomirov@128:  * the Free Software Foundation; version 2 of the License.
tikhomirov@128:  *
tikhomirov@128:  * This program is distributed in the hope that it will be useful,
tikhomirov@128:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
tikhomirov@128:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tikhomirov@128:  * GNU General Public License for more details.
tikhomirov@128:  *
tikhomirov@128:  * For information on how to redistribute this software under
tikhomirov@128:  * the terms of a license other than GNU General Public License
tikhomirov@128:  * contact TMate Software at support@hg4j.com
tikhomirov@128:  */
tikhomirov@128: package org.tmatesoft.hg.internal;
tikhomirov@128: 
tikhomirov@128: import java.util.TreeMap;
tikhomirov@128: 
tikhomirov@128: import org.tmatesoft.hg.core.Path;
tikhomirov@128: import org.tmatesoft.hg.repo.Changeset;
tikhomirov@128: import org.tmatesoft.hg.repo.HgDataFile;
tikhomirov@128: import org.tmatesoft.hg.repo.HgInternals;
tikhomirov@128: import org.tmatesoft.hg.repo.HgRepository;
tikhomirov@128: 
tikhomirov@128: /**
tikhomirov@128:  *
tikhomirov@128:  * @author Artem Tikhomirov
tikhomirov@128:  * @author TMate Software Ltd.
tikhomirov@128:  */
tikhomirov@128: public class ChangelogHelper {
tikhomirov@128: 	private final int leftBoundary;
tikhomirov@128: 	private final HgRepository repo;
tikhomirov@128: 	private final TreeMap<Integer, Changeset> cache = new TreeMap<Integer, Changeset>();
tikhomirov@128: 
tikhomirov@128: 	/**
tikhomirov@128: 	 * @param hgRepo
tikhomirov@128: 	 * @param leftBoundaryRevision walker never visits revisions with local numbers less than specified,
tikhomirov@128: 	 * IOW only revisions [leftBoundaryRevision..TIP] are considered.
tikhomirov@128: 	 */
tikhomirov@128: 	public ChangelogHelper(HgRepository hgRepo, int leftBoundaryRevision) {
tikhomirov@128: 		repo = hgRepo;
tikhomirov@128: 		leftBoundary = leftBoundaryRevision;
tikhomirov@128: 	}
tikhomirov@128: 	
tikhomirov@128: 	/**
tikhomirov@128: 	 * @return the repo
tikhomirov@128: 	 */
tikhomirov@128: 	public HgRepository getRepo() {
tikhomirov@128: 		return repo;
tikhomirov@128: 	}
tikhomirov@128: 
tikhomirov@128: 	/**
tikhomirov@128: 	 * Walks changelog in reverse order
tikhomirov@128: 	 * @param file
tikhomirov@128: 	 * @return changeset where specified file is mentioned among affected files, or 
tikhomirov@128: 	 * <code>null</code> if none found up to leftBoundary 
tikhomirov@128: 	 */
tikhomirov@128: 	public Changeset findLatestChangeWith(Path file) {
tikhomirov@128: 		HgDataFile df = repo.getFileNode(file);
tikhomirov@128: 		int changelogRev = df.getChangesetLocalRevision(HgRepository.TIP);
tikhomirov@128: 		if (changelogRev >= leftBoundary) {
tikhomirov@128: 			// the method is likely to be invoked for different files, 
tikhomirov@128: 			// while changesets might be the same. Cache 'em not to read too much. 
tikhomirov@128: 			Changeset cs = cache.get(changelogRev);
tikhomirov@128: 			if (cs == null) {
tikhomirov@128: 				cs = repo.getChangelog().range(changelogRev, changelogRev).get(0);
tikhomirov@128: 				cache.put(changelogRev, cs);
tikhomirov@128: 			}
tikhomirov@128: 			return cs;
tikhomirov@128: 		}
tikhomirov@128: 		return null;
tikhomirov@128: 	}
tikhomirov@128: 
tikhomirov@128: 	public String getNextCommitUsername() {
tikhomirov@128: 		return new HgInternals(repo).getNextCommitUsername();
tikhomirov@128: 	}
tikhomirov@128: }