--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/tmatesoft/hg/repo/ext/Rebase.java	Mon Oct 29 19:04:13 2012 +0100
@@ -0,0 +1,140 @@
+/*
+ * Copyright (c) 2012 TMate Software Ltd
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * For information on how to redistribute this software under
+ * the terms of a license other than GNU General Public License
+ * contact TMate Software at support@hg4j.com
+ */
+package org.tmatesoft.hg.repo.ext;
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.NoSuchElementException;
+
+import org.tmatesoft.hg.core.HgBadNodeidFormatException;
+import org.tmatesoft.hg.core.HgIOException;
+import org.tmatesoft.hg.core.Nodeid;
+import org.tmatesoft.hg.internal.Internals;
+import org.tmatesoft.hg.internal.LineReader;
+import org.tmatesoft.hg.repo.HgInvalidFileException;
+import org.tmatesoft.hg.repo.HgInvalidStateException;
+
+/**
+ * Support for standard Rebase extension.
+ * 
+ * @see http://mercurial.selenic.com/wiki/RebaseExtension
+ * @since 1.1
+ * @author Artem Tikhomirov
+ * @author TMate Software Ltd.
+ */
+public class Rebase {
+	private Internals repo;
+	private Nodeid workingDirParent;
+	private Nodeid destRevision;
+	private Nodeid externalParent;
+	private Map<Nodeid, Nodeid> state;
+	private boolean collapse;
+	private boolean keepOriginalRevisions;
+	private boolean keepBranchNames;
+	
+	/*package-local*/ Rebase(Internals internalRepo) {
+		repo = internalRepo;
+	}
+
+	public Rebase refresh() throws HgIOException {
+		workingDirParent = null;
+		destRevision = null;
+		externalParent = null;
+		state = null;
+		File f = repo.getFileFromRepoDir("rebasestate");
+		if (!f.exists()) {
+			return this;
+		}
+		state = new HashMap<Nodeid, Nodeid>();
+		try {
+			LineReader lr = new LineReader(f, repo.getSessionContext().getLog());
+			ArrayList<String> contents = new ArrayList<String>();
+			lr.read(new LineReader.SimpleLineCollector(), contents);
+			Iterator<String> it = contents.iterator();
+			workingDirParent = Nodeid.fromAscii(it.next());
+			destRevision = Nodeid.fromAscii(it.next());
+			externalParent = Nodeid.fromAscii(it.next());
+			collapse = "1".equals(it.next());
+			keepOriginalRevisions = "1".equals(it.next());
+			keepBranchNames = "1".equals(it.next());
+			final String nullmerge = "-2";
+			while (it.hasNext()) {
+				String line = it.next();
+				int x = line.indexOf(':');
+				if (x == -1) {
+					throw new HgInvalidStateException(line);
+				}
+				Nodeid oldRev = Nodeid.fromAscii(line.substring(0, x));
+				Nodeid newRev;
+				if (line.regionMatches(x+1, nullmerge, 0, nullmerge.length())) {
+					newRev = null;
+				} else {
+					newRev = Nodeid.fromAscii(line.substring(x+1));
+				}
+				state.put(oldRev, newRev);
+			}
+		} catch (NoSuchElementException ex) {
+			throw new HgIOException("Bad format of rebase state file", f);
+		} catch (HgBadNodeidFormatException ex) {
+			throw new HgIOException("Bad format of rebase state file", ex, f);
+		} catch (HgInvalidFileException ex) {
+			throw new HgIOException("Bad format of rebase state file", ex, f);
+		}
+		return this;
+	}
+	
+	/**
+	 * Tells whether rebase process was interrupted to manually resolve a merge 
+	 * and can be resumed or aborted.
+	 * 
+	 * @return <code>true</code> when rebase is in progress 
+	 */
+	public boolean isRebaseInProgress() {
+		return state != null;
+	}
+
+	public Nodeid getWorkingDirParent() {
+		assert isRebaseInProgress();
+		return workingDirParent;
+	}
+	
+	public Nodeid getTarget() {
+		assert isRebaseInProgress();
+		return destRevision;
+	}
+	
+	public Nodeid getExternalParent() {
+		assert isRebaseInProgress();
+		assert collapse;
+		return externalParent;
+	}
+	
+	public boolean isCollapse() {
+		return collapse;
+	}
+	
+	public boolean isKeepOriginalRevisions() {
+		return keepOriginalRevisions;
+	}
+
+	public boolean isKeepBranchNames() {
+		return keepBranchNames;
+	}
+}