--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/tmatesoft/hg/repo/Changeset.java	Mon Jan 24 03:14:45 2011 +0100
@@ -0,0 +1,228 @@
+/*
+ * Copyright (c) 2010-2011 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@svnkit.com
+ */
+package org.tmatesoft.hg.repo;
+
+import java.io.UnsupportedEncodingException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Date;
+import java.util.Formatter;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+
+import org.tmatesoft.hg.core.Nodeid;
+
+/**
+ * @see mercurial/changelog.py:read()
+ * <pre>
+        format used:
+        nodeid\n        : manifest node in ascii
+        user\n          : user, no \n or \r allowed
+        time tz extra\n : date (time is int or float, timezone is int)
+                        : extra is metadatas, encoded and separated by '\0'
+                        : older versions ignore it
+        files\n\n       : files modified by the cset, no \n or \r allowed
+        (.*)            : comment (free text, ideally utf-8)
+
+        changelog v0 doesn't use extra
+ * </pre>
+ *
+ * @author Artem Tikhomirov
+ * @author TMate Software Ltd.
+ */
+public class Changeset implements Cloneable /*for those that would like to keep a copy*/ {
+	// TODO immutable
+	private /*final*/ Nodeid manifest;
+	private String user;
+	private String comment;
+	private List<String> files; // unmodifiable collection (otherwise #files() and implicit #clone() shall be revised)
+	private Date time;
+	private int timezone; // not sure it's of any use
+	private Map<String,String> extras;
+	
+	private Changeset() {
+	}
+	
+	public Nodeid manifest() {
+		return manifest;
+	}
+	
+	public String user() {
+		return user;
+	}
+	
+	public String comment() {
+		return comment;
+	}
+	
+	public List<String> files() {
+		return files;
+	}
+
+	public Date date() {
+		return time;
+	}
+	
+	public String dateString() {
+		StringBuilder sb = new StringBuilder(30);
+		Formatter f = new Formatter(sb, Locale.US);
+		f.format("%ta %<tb %<td %<tH:%<tM:%<tS %<tY %<tz", time);
+		return sb.toString();
+	}
+
+	public Map<String, String> extras() {
+		return extras;
+	}
+	
+	public String branch() {
+		return extras.get("branch");
+	}
+	
+	@Override
+	public String toString() {
+		StringBuilder sb = new StringBuilder();
+		sb.append("Changeset {");
+		sb.append("User: ").append(user).append(", ");
+		sb.append("Comment: ").append(comment).append(", ");
+		sb.append("Manifest: ").append(manifest).append(", ");
+		sb.append("Date: ").append(time).append(", ");
+		sb.append("Files: ").append(files.size());
+		for (String s : files) {
+			sb.append(", ").append(s);
+		}
+		if (extras != null) {
+			sb.append(", Extra: ").append(extras);
+		}
+		sb.append("}");
+		return sb.toString();
+	}
+	
+	@Override
+	public Changeset clone() {
+		try {
+			return (Changeset) super.clone();
+		} catch (CloneNotSupportedException ex) {
+			throw new InternalError(ex.toString());
+		}
+	}
+
+	public static Changeset parse(byte[] data, int offset, int length) {
+		Changeset rv = new Changeset();
+		rv.init(data, offset, length);
+		return rv;
+	}
+
+	/*package-local*/ void init(byte[] data, int offset, int length) {
+		final int bufferEndIndex = offset + length;
+		final byte lineBreak = (byte) '\n';
+		int breakIndex1 = indexOf(data, lineBreak, offset, bufferEndIndex);
+		if (breakIndex1 == -1) {
+			throw new IllegalArgumentException("Bad Changeset data");
+		}
+		Nodeid _nodeid = Nodeid.fromAscii(data, 0, breakIndex1);
+		int breakIndex2 = indexOf(data, lineBreak, breakIndex1+1, bufferEndIndex);
+		if (breakIndex2 == -1) {
+			throw new IllegalArgumentException("Bad Changeset data");
+		}
+		String _user = new String(data, breakIndex1+1, breakIndex2 - breakIndex1 - 1);
+		int breakIndex3 = indexOf(data, lineBreak, breakIndex2+1, bufferEndIndex);
+		if (breakIndex3 == -1) {
+			throw new IllegalArgumentException("Bad Changeset data");
+		}
+		String _timeString = new String(data, breakIndex2+1, breakIndex3 - breakIndex2 - 1);
+		int space1 = _timeString.indexOf(' ');
+		if (space1 == -1) {
+			throw new IllegalArgumentException("Bad Changeset data");
+		}
+		int space2 = _timeString.indexOf(' ', space1+1);
+		if (space2 == -1) {
+			space2 = _timeString.length();
+		}
+		long unixTime = Long.parseLong(_timeString.substring(0, space1)); // XXX Float, perhaps
+		int _timezone = Integer.parseInt(_timeString.substring(space1+1, space2));
+		// XXX not sure need to add timezone here - I can't figure out whether Hg keeps GMT time, and records timezone just for info, or unixTime is taken local
+		// on commit and timezone is recorded to adjust it to UTC.
+		Date _time = new Date(unixTime * 1000);
+		String _extras = space2 < _timeString.length() ? _timeString.substring(space2+1) : null;
+		Map<String, String> _extrasMap;
+		if (_extras == null) {
+			 _extrasMap = Collections.singletonMap("branch", "default"); 
+		} else {
+			_extrasMap = new HashMap<String, String>();
+			for (String pair : _extras.split("\00")) {
+				int eq = pair.indexOf(':');
+				// FIXME need to decode key/value, @see changelog.py:decodeextra
+				_extrasMap.put(pair.substring(0, eq), pair.substring(eq+1));
+			}
+			if (!_extrasMap.containsKey("branch")) {
+				_extrasMap.put("branch", "default");
+			}
+			_extrasMap = Collections.unmodifiableMap(_extrasMap);
+		}
+		
+		//
+		int lastStart = breakIndex3 + 1;
+		int breakIndex4 = indexOf(data, lineBreak, lastStart, bufferEndIndex);
+		ArrayList<String> _files = new ArrayList<String>(5);
+		while (breakIndex4 != -1 && breakIndex4 + 1 < bufferEndIndex) {
+			_files.add(new String(data, lastStart, breakIndex4 - lastStart));
+			lastStart = breakIndex4 + 1;
+			if (data[breakIndex4 + 1] == lineBreak) {
+				// found \n\n
+				break;
+			} else {
+				breakIndex4 = indexOf(data, lineBreak, lastStart, bufferEndIndex);
+			}
+		}
+		if (breakIndex4 == -1 || breakIndex4 >= bufferEndIndex) {
+			throw new IllegalArgumentException("Bad Changeset data");
+		}
+		String _comment;
+		try {
+			_comment = new String(data, breakIndex4+2, bufferEndIndex - breakIndex4 - 2, "UTF-8");
+		} catch (UnsupportedEncodingException ex) {
+			_comment = "";
+			throw new IllegalStateException("Could hardly happen");
+		}
+		// change this instance at once, don't leave it partially changes in case of error
+		this.manifest = _nodeid;
+		this.user = _user;
+		this.time = _time;
+		this.timezone = _timezone;
+		this.files = Collections.unmodifiableList(_files);
+		this.comment = _comment;
+		this.extras = _extrasMap;
+	}
+
+	private static int indexOf(byte[] src, byte what, int startOffset, int endIndex) {
+		for (int i = startOffset; i < endIndex; i++) {
+			if (src[i] == what) {
+				return i;
+			}
+		}
+		return -1;
+	}
+
+	public interface Inspector {
+		// first(), last(), single().
+		// <T>
+		// TODO describe whether cset is new instance each time
+		void next(int revisionNumber, Nodeid nodeid, Changeset cset);
+	}
+}