--- a/cmdline/org/tmatesoft/hg/console/Main.java	Mon Jun 18 20:26:59 2012 +0200
+++ b/cmdline/org/tmatesoft/hg/console/Main.java	Wed Jun 20 21:16:21 2012 +0200
@@ -65,6 +65,8 @@
 import org.tmatesoft.hg.repo.HgStatusInspector;
 import org.tmatesoft.hg.repo.HgSubrepoLocation;
 import org.tmatesoft.hg.repo.HgSubrepoLocation.Kind;
+import org.tmatesoft.hg.repo.ext.MqManager;
+import org.tmatesoft.hg.repo.ext.MqManager.PatchRecord;
 import org.tmatesoft.hg.repo.HgWorkingCopyStatusCollector;
 import org.tmatesoft.hg.util.FileWalker;
 import org.tmatesoft.hg.util.LogFacility;
@@ -96,11 +98,10 @@
 
 	public static void main(String[] args) throws Exception {
 		Main m = new Main(args);
+		m.testMqManager();
 //		m.testRevisionDescendants();
-		for (int i : new int[] {1,2,3,4,5}) {
-//			m.dumpPhases();
-			m.buildFileLog();
-		}
+//		m.dumpPhases();
+//		m.buildFileLog();
 //		m.testConsoleLog();
 //		m.testTreeTraversal();
 //		m.testRevisionMap();
@@ -122,6 +123,25 @@
 //		m.bunchOfTests();
 	}
 	
+	
+	// TODO as junit tests in 'default'
+	// -R ${system_property:user.home}/hg/test-mq
+	private void testMqManager() throws Exception {
+		MqManager mqManager = new MqManager(hgRepo);
+		mqManager.refresh();
+		int i = 1;
+		System.out.println("Complete patch queue:");
+		for (PatchRecord pr : mqManager.getAllKnownPatches()) {
+			System.out.printf("#%-3d %s from %s\n", i++, pr.getName(), pr.getPatchLocation());
+		}
+		i = 1;
+		System.out.println("Patches from the queue already applied to the repo:");
+		for (PatchRecord pr : mqManager.getAppliedPatches()) {
+			System.out.printf("#%-3d %s, known as cset:%s\n", i++, pr.getName(), pr.getRevision().shortNotation());
+		}
+	}
+	
+	
 	// -R {junit-test-repos}/branches-1
 	private void testRevisionDescendants() throws Exception {
 		int[] roots = new int[] {0, 1, 2, 3, 4, 5};

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/tmatesoft/hg/repo/ext/MqManager.java	Wed Jun 20 21:16:21 2012 +0200
@@ -0,0 +1,200 @@
+/*
+ * 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.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+
+import org.tmatesoft.hg.core.HgInvalidControlFileException;
+import org.tmatesoft.hg.core.HgInvalidFileException;
+import org.tmatesoft.hg.core.Nodeid;
+import org.tmatesoft.hg.repo.HgInternals;
+import org.tmatesoft.hg.repo.HgRepository;
+import org.tmatesoft.hg.util.LogFacility;
+import org.tmatesoft.hg.util.Path;
+
+/**
+ * Mercurial Queues Support. 
+ * Access to MqExtension functionality.
+ * 
+ * @author Artem Tikhomirov
+ * @author TMate Software Ltd.
+ */
+public class MqManager {
+	
+	private final HgRepository repo;
+	private List<PatchRecord> applied = Collections.emptyList();
+	private List<PatchRecord> allKnown = Collections.emptyList();
+
+	public MqManager(HgRepository hgRepo) {
+		repo = hgRepo;
+	}
+	
+	/**
+	 * Updates manager with up-to-date state of the mercurial queues.
+	 */
+	public void refresh() throws HgInvalidControlFileException {
+		File repoDir = HgInternals.getRepositoryDir(repo);
+		final LogFacility log = HgInternals.getContext(repo).getLog();
+		final File fileStatus = new File(repoDir, "patches/status");
+		final File fileSeries = new File(repoDir, "patches/series");
+		try {
+			if (fileStatus.isFile()) {
+				new LineReader(fileStatus, log).read(new LineConsumer<List<PatchRecord>>() {
+	
+					public boolean consume(String line, List<PatchRecord> result) throws IOException {
+						int sep = line.indexOf(':');
+						if (sep == -1) {
+							log.warn(MqManager.class, "Bad line in %s:%s", fileStatus.getPath(), line);
+							return true;
+						}
+						Nodeid nid = Nodeid.fromAscii(line.substring(0, sep));
+						String name = new String(line.substring(sep+1));
+						result.add(new PatchRecord(nid, name, Path.create(".hg/patches/" + name)));
+						return true;
+					}
+				}, applied = new LinkedList<PatchRecord>());
+			}
+			if (fileSeries.isFile()) {
+				new LineReader(fileSeries, log).read(new LineConsumer<List<PatchRecord>>() {
+
+					public boolean consume(String line, List<PatchRecord> result) throws IOException {
+						result.add(new PatchRecord(null, line, Path.create(".hg/patches/" + line)));
+						return true;
+					}
+				}, allKnown = new LinkedList<PatchRecord>());
+			}
+		} catch (HgInvalidFileException ex) {
+			HgInvalidControlFileException th = new HgInvalidControlFileException(ex.getMessage(), ex.getCause(), ex.getFile());
+			th.setStackTrace(ex.getStackTrace());
+			throw th;
+		}
+	}
+
+	/**
+	 * Subset of the patches from the queue that were already applied to the repository
+	 * 
+	 * <p>Clients shall call {@link #refresh()} prior to first use
+	 * @return collection of records in no particular order, may be empty if none applied
+	 */
+	public List<PatchRecord> getAppliedPatches() {
+		return Collections.unmodifiableList(applied);
+	}
+	
+	/**
+	 * All of the patches that MQ knows about for this repository
+	 * 
+	 * <p>Clients shall call {@link #refresh()} prior to first use
+	 * @return collection of records in no particular order, may be empty if there are no patches in the queue
+	 */
+	public List<PatchRecord> getAllKnownPatches() {
+		return Collections.unmodifiableList(allKnown);
+	}
+	
+	public class PatchRecord {
+		private final Nodeid nodeid;
+		private final String name;
+		private final Path location;
+
+		PatchRecord(Nodeid revision, String name, Path diffLocation) {
+			nodeid = revision;
+			this.name = name;
+			this.location = diffLocation;
+		}
+
+		/**
+		 * Identifies changeset of the patch that has been applied to the repository
+		 * 
+		 * @return changeset revision or <code>null</code> if this patch is not yet applied
+		 */
+		public Nodeid getRevision() {
+			return nodeid;
+		}
+
+		/**
+		 * Identifies patch, either based on a user-supplied name (<code>hg qnew <i>patch-name</i></code>) or 
+		 * an automatically generated name (like <code><i>revisionIndex</i>.diff</code> for imported changesets).
+		 * Clients shall not rely on this naming scheme, though.
+		 * 
+		 * @return never <code>null</code>
+		 */
+		public String getName() {
+			return name;
+		}
+		
+		/**
+		 * Location of diff file with the patch, relative to repository root
+		 * @return path to the patch, never <code>null</code>
+		 */
+		public Path getPatchLocation() {
+			return location;
+		}
+	}
+
+	// TODO refine API and extract into separate classes
+
+	interface LineConsumer<T> {
+//		boolean begin(File f, T paramObj) throws IOException;
+		boolean consume(String line, T paramObj) throws IOException;
+//		boolean end(File f, T paramObj) throws IOException;
+	}
+	
+	class LineReader {
+		
+		private final File file;
+		private final LogFacility log;
+
+		LineReader(File f, LogFacility logFacility) {
+			file = f;
+			log = logFacility;
+		}
+
+		<T> void read(LineConsumer<T> consumer, T paramObj) throws HgInvalidFileException {
+			BufferedReader statusFileReader = null;
+			try {
+//				consumer.begin(file, paramObj);
+				statusFileReader = new BufferedReader(new FileReader(file));
+				String line;
+				boolean ok = true;
+				while (ok && (line = statusFileReader.readLine()) != null) {
+					line = line.trim();
+					if (line.length() > 0) {
+						ok = consumer.consume(line, paramObj);
+					}
+				}
+			} catch (IOException ex) {
+				throw new HgInvalidFileException(ex.getMessage(), ex, file);
+			} finally {
+				try {
+					statusFileReader.close();
+				} catch (IOException ex) {
+					log.warn(MqManager.class, ex, null);
+				}
+//				try {
+//					consumer.end(file, paramObj);
+//				} catch (IOException ex) {
+//					log.warn(MqManager.class, ex, null);
+//				}
+			}
+		}
+	}
+}